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CHAPTER B
HUMAN DEVELOPMENT AND THE ENVIRONMENT THROUGHOUT HISTORY
2.1. Introduction
It is nave to think that our current environmental problems are entirely new. Accounts of past
civilizations are full of examples of misuse and overuse of resources and ecosystem services, and
the consequences of those mistakes. Thus even though modern humanity has never before
experienced large scale problems like loss of biodiversity, stratospheric ozone depletion, peak oil,
and climate change, we nevertheless can look at human development on a local scale throughout
history to learn about the possible impacts of our current actions. And since we are now dealing
with changes on a planetary rather than local scale, the stakes are obviously much higher today.
We will use the terms resources and ecosystem services in this chapter and throughout the book. By
resources we mean energy, materials, land, water, and air that we use to satisfy our needs. By
ecosystem services we mean natural processes that occur in the biosphere that enable our lives and
livelihoods to continue, such as the ability of the earth to serve as a sink for the wastes of
civilization. For example, water contaminated by human or animal excreta will become purified as
it is transported by rivers, streams, or groundwater over a period of time. This occurs because the
wastes serve as nutrients for certain bacteria and fungi, organisms that decompose the waste
products so their constituents can be used again. Other types of contamination in water, such as
chemical waste, may take shorter or longer periods of time to decompose, depending on the type of
contaminant. If the amount of waste is too great or the contaminant is resistant to degradation,
however, the natural purification processes may be overwhelmed, in which case the ecosystem can
no longer provide this service for a period of time.
In this Chapter, we consider the human use of natural resources and ecosystem services throughout
history, briefly touching on key issues in a few of the western worlds most notable civilizations.
We mention relevant social issues and political forces as well as environmental attitudes while
reviewing this history to put human-environment interactions in context. We then explore how the
failures and successes of the past can be used to assist in understanding the current dilemma. The
material presented in this chapter is taken from the literature in environmental history, a rich area of
study that includes the two-way interactions of how the environment affects people and how people
affect the environment, and also includes human attitudes and thoughts about the environment.
Although we focus on the western world to provide most of the examples, the same lessons can be
learned by examining civilizations that existed in China, Africa, North and South America, and
elsewhere.
2.2. Jericho, Anatolia, and Mesopotamia up to 1500 BCE
Agriculture began with the discovery that seeds of certain crops could be planted and grown
reliably, producing food for large numbers of people. This realization, considered by some to be the
most important discovery in human history, transformed homo sapiens from a nomadic, hunter1
Intro. to Sustainable Engineering by Cliff Davidson et al., January 11, 2011. Copyright Protected.
gatherer lifestyle to an urban culture. The transformation occurred sometime prior to 8000 BCE in
the Stone Age.
The rise of towns and cities caused a fundamental change in human relationship with the
environment. Rather than living as a part of the ecosystem by hunting animals and gathering
naturally growing plants as they moved from place to place, people could settle at one location and
replace the natural ecosystem there with houses, streets, and commercial establishments (Melosi,
1993). They could construct farms and waterways to provide food and water. They could also
domesticate wild animals for their own purposes.
The worlds oldest known settlement, Jericho, originated sometime before 8000 BCE in what is
now the West Bank of the Jordan River (Sass, 1998, pp. 25-29). The town had at least 2,000
inhabitants who lived in houses of mud brick with their floors well below ground level. The entire
town occupied an area of about ten acres, or roughly four hectares. Wild grains, especially wheat,
grew in the hills near Jericho and originally provided food for the townspeople. The physical
structure of the wheat plants provides information about human use of this grain: the plants that
originally grew near Jericho had heads which easily shatter when the seeds ripen, allowing the seeds
to fall to the ground and become the next generation of plants. Due to mutations, some of the plants
had heads that did not shatter; archaeological evidence shows that the villagers collected these
plants and cultivated them in the land around Jericho, since the wheat from these hardier plants
could be more easily harvested. Thus human interference in natural plant cycles by spreading the
occurrence of mutated plants is as old as agriculture itself.
Domestication of wheat became widespread and allowed larger communities to develop. The town
of Catal Hyk in Anatolia, modern-day Turkey, had a population of more than 5,000. These people
grew grains and domesticated animals including aurochs, which were wild cattle with horns up to
two meters long. Perhaps as important as growing and harvesting grains, people in this region
developed new methods of storing large amounts of grain and other food out of the reach of
animals. This was achieved by making clay pots and other ceramics as early as 6500 BCE (Sass,
1998, pp. 52-55). The beginning of ceramics ushered in the final period of the Stone Age known as
the Neolithic Period. The inside of a modern reconstruction of a Catal Hyk dwelling from the
Neolithic Period is shown in Figure 1.
The Sumerians were among the first people to develop cities with many thousands of inhabitants
(Hughes, 2001, pp. 34-37; Chew, 2007, p. 67). They occupied Mesopotamia, which literally means
between the rivers in Greek, the region between the Tigris and Euphrates Rivers in modern-day
Iraq. The inhabitants made extensive use of the earths resources. For example, the southern
Mesopotamian city of Uruk had roughly 25,000 to 40,000 inhabitants who constructed large palaces
and temples. They made wooden plows for farming, domesticated oxen to pull their plows, and
built networks of canals for irrigation. The built-up area of the city occupied only about 200
hectares, but the land surrounding the city for many kilometers was used for growing wheat, barley,
and other grains to support the urban dwellers. In addition, evidence of the earliest written language
was found in Uruk: clay tablets containing pictographs, or pictures representing objects, date back
to the early fourth millennium BCE. It is believed that these tablets were used to keep track of
cattle, sheep, grain, and other farm goods. Over time the pictographs became simplified to wedge-
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shaped symbols, known as cuneiform writing (after cuneus, Latin for wedge). Figure 2 shows a
map of archaeological sites in Mesopotamia, where ancient communities existed.
Figure 1. Interior of a reconstructed Neolithic Period dwelling in Catal Hyk, Turkey. The house
was built below ground level, with access by a ladder as shown. Note the smooth plaster walls and
timber roof. Photo taken in January 2003, accessed September 2008 at:
http://en.wikipedia.org/wiki/Image:Catal_H%C3%BCy%C3%BCk_Restauration_B.JPG. Licensed
under GNU Free Documentation License version 1.2 available at:
http://commons.wikimedia.org/wiki/Commons:GNU_Free_Documentation_License.
The Sumerians were among the first people to develop cities with many thousands of inhabitants
(Hughes, 2001, pp. 34-37; Chew, 2007, p. 67). They occupied Mesopotamia, which literally means
between the rivers in Greek, the region between the Tigris and Euphrates Rivers in modern-day
Iraq. The inhabitants made extensive use of the earths resources. For example, the southern
Mesopotamian city of Uruk had roughly 25,000 to 40,000 inhabitants who constructed large palaces
and temples. They made wooden plows for farming, domesticated oxen to pull their plows, and
built networks of canals for irrigation. The built-up area of the city occupied only about 200
hectares, but the land surrounding the city for many kilometers was used for growing wheat, barley,
and other grains to support the urban dwellers. In addition, evidence of the earliest written language
was found in Uruk: clay tablets containing pictographs, or pictures representing objects, date back
to the early fourth millennium BCE. It is believed that these tablets were used to keep track of
cattle, sheep, grain, and other farm goods. Over time the pictographs became simplified to wedgeshaped symbols, known as cuneiform writing (after cuneus, Latin for wedge). Figure 2 shows a
map of archaeological sites in Mesopotamia, where ancient communities existed.
People in Mesopotamia, Anatolia, and adjacent regions are credited with the first advancements in
the art of working with metals, mainly for weapons and agricultural tools, starting with copper as
early as 7000 BCE (Wertime, 1973). Metalworking began with hammering or otherwise shaping a
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native metal, then progressed to annealing, or heating the metal in a fire to make it easier to shape,
which eventually gave way to casting where the metal is raised to a temperature above its melting
point so it becomes a liquid. The discovery of casting may have occurred inadvertently when native
copper subjected to annealing reached its melting temperature of 1083oC and melted into the fire.
This probably occurred sometime in the sixth or fifth millennium BCE. Another important
discovery occurred when it was found that certain rocks contained metals that could be smelted at a
high temperature to separate the pure metal from the ore. Ores containing copper and lead were
among the first ones to be smelted around 4000 BCE, as certain ores of both metals have reduction
temperatures around 1200 to 1300oC. The discovery that alloys of two or more metals could be
stronger than either metal separately probably occurred when early metallurgists smelted copper
ores containing traces of arsenic, and created a form of bronze. By 3200 BCE, the ancients had
developed a more reliable bronze by adding tin to copper. It is believed that the tin was imported
from great distances since this metal is not plentiful in the Middle East, although the source
locations remain unknown. The discovery of reliable bronze marked the end of the Stone Age and
beginning of the Bronze Age in the Middle East. Even with this discovery, copper and copperarsenic bronze were far more widely used than copper-tin bronze for another one thousand years.
Note that the successful development of bronze took place at different times elsewhere in the world,
e.g., the Bronze Age in Britain began several hundred years later (Tylecote, 1987).
By 3000 BCE in Mesopotamia, lead and silver were mined and smelted, and copper was smelted
and widely used for weapons, vases, mirrors, and tools of agriculture such as hoes and plows (Sass,
1998, pp. 59-61). The copper industry relied on imports, as there are very few naturally occurring
copper ores in the region. Traders brought ores, probably copper oxides and copper carbonates,
from Cyprus, Anatolia, and the Negev Desert. Because of its expense, metalworkers in
Mesopotamia recycled large amounts of copper, keeping imports to a minimum. Sometime in the
third millennium, the easily smelted oxide and carbonate ores became exhausted. This caused
smelters to switch to copper sulfide ores from Anatolia which were more difficult to work with, but
which were plentiful so that the copper industry grew markedly as technological innovations gained
momentum. By 2000 BCE, copper from Anatolia was being mass produced in large quantities for
communities thousands of kilometers away.
A limiting factor in the smelting of copper in ancient times was the availability of fuel. The ancients
knew that wood could be converted to charcoal by burning it slowly in the absence of air, e.g., in
covered pits dug into the earth. Charcoal burns hotter than wood, it provides more even heat, and its
heat output is easier to control compared to wood (Olson, 1991), making it the fuel of choice in
metalworking. Historians estimate that it took 20 kg of charcoal to make each kg of copper, and
about 7 kg of wood to make each kg of charcoal (Sass, 1998, pp. 52-55; Hughes, 2001, pp. 31-32).
These fuel requirements were a major inconvenience for the Sumerians, as there is little woodland
in the arid regions in Mesopotamia, necessitating transport from distant forests.
Availability of wood was probably a limiting factor in other aspects of urban life in this part of the
world. Buildings required wood timbers for roof support and for scaffolding during construction.
Houses were made of mud brick, some of which were kiln-fired using charcoal made from wood,
and had plaster walls and terrazzo floors both of which required kiln firing (Wertime, 1983). Giant
kilns for making roof tiles were built, requiring huge amounts of wood for firing. In addition, the
manufacture of mortar for bricks employed kiln firing, although the Sumerians discovered that
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Intro. to Sustainable Engineering by Cliff Davidson et al., January 11, 2011. Copyright Protected.
bitumen seeping from their vast but unknown oil fields was a better adhesive for their construction
(Sass, 1998, pp. 126-127). All of this information suggests that the great demand for wood led to
serious deforestation. Note that other civilizations at this time used wood directly as a building
material, such as those in central and northern Europe. Examples of Stone Age houses reconstructed
from archaeological findings in modern-day Germany are shown in Figure 3.
Figure 2. Archaeological sites in Mesopotamia. Note that most of the sites, which are locations of
ancient communities, are in the fertile area between the Tigris and Euphrates Rivers. Map accessed
September 2008 at: http://commons.wikimedia.org/wiki/Image:Lagash.JPG. Licensed under GNU
Free Documentation License version 1.2 available at:
http://commons.wikimedia.org/wiki/Commons:GNU_Free_Documentation_License.
It is unlikely that these early civilizations were concerned about preserving their forests, or for that
matter about preserving any part of their environment. Rather they were proud of their ability to
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triumph over nature through their buildings, canals, and metalworking. The artwork and writing of
the Sumerians reflect this attitude. For example, the ancient Sumerian story of the earths creation
describes a battle between Tiamat, the female monster of chaotic nature and Marduk, the champion
of the new order of the gods. Marduk slays Tiamat and builds a city of the gods in the sky. The
story reflects the concept of a city as a model of divine order with its trim buildings and straight
streets, while nature in contrast is chaotic. A wall of 9.6 km length encircling Uruk was built as
much as a divider between urban civilization and the wilds of the outside world as much as it was to
protect the city from attackers (Hughes, 2001, pp. 34-37).
Figure 3. Two replicas of Stone Age houses at the Pfahlbaumuseum on Lake Constance, Germany.
The Hornstaad House on the left was built on 1996, a pole building with walls of woven wattle
(tree branches) coated with clay. Roofs of these houses were made of thatch, turf, grass, or rushes.
The Arbon House on the right was built in 1998, also a pole building with walls made of wooden
boards and a shingle roof. Photo accessed September 2008 at http://www.pfahlbauten.com/lakedwelling-museum/stone-age-arbon-house-hornstaad-house.html.
Disregard for the environment was a serious problem, but it was not the only one. Historians have
noted that many civilizations in this part of the world flourished during a time known as the
Neolithic Wet Period that began prior to 7000 BCE and ended in stages in the period 2900-2350
BCE (Butzer, 1966; Bell, 1971). Precipitation was greater during this interval of four millennia than
either before or after it. The Neolithic Wet Period ended not with a return to normal precipitation,
but with a severe drought beginning around 2200 BCE that affected wide regions of the eastern
Mediterranean and beyond. In southern Mesopotamia, the combination of the drought and
environmental degradation took its toll. Salt in the irrigation water and the soil of the Sumerian
fields had built up to high levels by this time. The salinity was made worse by deforestation in the
surrounding mountains, which exposed salt-bearing rocks to rainfall. In addition, accumulation of
silt in the canals over time caused poor drainage, making it difficult to leach the accumulated salt
with the addition of more fresh water. Much of the agricultural land was a considerable distance
from the flood plain of the rivers and thus received very little water other than what was provided
by irrigation. Crop yields declined from 2400 BCE to 1700 BCE, and ultimately the civilization
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could not feed itself (Jacobsen and Adams, 1958): the population fell precipitously, urban dwellers
migrated to rural areas in search of food, and industrial as well as agricultural activities were closed
or scaled back to minimal levels. The collapse of the Sumerian civilization was complete by around
1700 BCE.
The disintegration of the Sumerian economy is but one of several civilizations that suffered
hardship around this time. The ancient civilization at Levant in modern-day Syria fell in the period
2200 BCE to 1700 BCE, and the Harappan civilization in northwest India, which was active in
trading with the Mediterranean region, experienced collapse during 1700 BCE to 1500 BCE. It has
been proposed that the civilizations occupying the land mass from Greece and Egypt eastward to
India represent essentially a world system at this time, having most of the global economic output
(Chew, 2007, p. 73). The failure of these economic systems probably occurred due to environmental
damage caused by human activity as well as natural variability in climate. The environmental
damage resulted from overcultivation, overgrazing, deforestation, contaminating the landscape
through mining, and poor water management, while natural variability in climate caused drought
and other changes in the earth systems.
2.3 Ancient Egypt, 3300 BCE 30 BCE
The beginning of a highly productive civilization in ancient Egypt began around 3300 BCE. While
the Sumerians were building canals and irrigating cropland in Mesopotamia, the Egyptians were
taking advantage of the Nile River to establish their system of agriculture. Like the Sumerians, the
Egyptians constructed canals to bring water from the Nile to their fields during all seasons. In fact,
the two civilizations traded with each other and shared their technologies. But most of the Egyptian
fields were on the flood plain of the Nile, and the Nile flooded with regularity in late July or early
August every year (Hughes, 2001, pp. 39-41). This flood deposited rich alluvial soil from the
upstream mountains and swamps onto the fields, and ensured continual nutrients to nourish the next
years crops. The Egyptians also cultivated flax to make linen for clothing. They used mud from
the banks of the river, dried in the sun or in kilns, to make bricks and pottery. In addition, they
cultivated a certain type of reed growing around the Nile which was used to make papyrus, a form
of paper. The Egyptians developed hieroglyphics, their written language, on stone and papyrus. The
paints used for hieroglyphics and other artwork were made from various naturally occurring
minerals as well as plants (Lucas and Harris, 1999, pp. 340-348). For example, black paint was
made of carbon soot from fires, blue paint was from the copper-containing minerals azurite and
malachite, and red paint was produced from iron and lead oxides. Figure 4 shows a map of the
communities of ancient Egypt, while Figure 5 shows an example of hieroglyphics as part of a
funerary tablet.
The Egyptians learned metallurgy from the Sumerians, and then improved on it. They made many
implements from copper dishes, cookware, saws, chisels, knives, as well as hoes and sickles
(Dartmouth College, 2010). They also made copper-arsenic bronze and copper-tin bronze. But the
Egyptians are perhaps best known for their metalworking in gold. Many of the pharaohs were
buried with gold ornaments, as such ornaments were among their most prized possessions.
Unfortunately, knowledge of this fact led to pillaging of many of their tombs (Sass, 1998, p. 69).
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Figure 4. Map of the communities of ancient Egypt, accessed September 2008 at:
http://commons.wikimedia.org/wiki/Image:Ancient_Egypt.png. Licensed under GNU Free
Documentation License version 1.2 available at:
http://commons.wikimedia.org/wiki/Commons:GNU_Free_Documentation_License.
Figure 5. The Stele of Revealing, a funerary tablet with painted hieroglyphics made in about 725
BCE by the priest Ankh-af-na-khonsu from Thebes (near present-day Luxor). The tablet was
created for the purpose of commemorating the creators own death. The priest is depicted by the
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figure standing on the right. Photograph accessed September 2008 at:
http://en.wikipedia.org/wiki/Image:Stele_of_revealing.jpg. This photograph is in the public domain.
Enormous amounts of resources were needed to construct the ancient pyramids beginning in around
2650 BCE. The largest pyramids, those built for the pharaohs Khufu and Khafre roughly a century
later, are located at Giza which is just south of modern-day Cairo (Lehner, 1998, pp. 206-207). Two
smaller pyramids are nearby, namely those of the pharaohs Menkaure and Khentkawes. The
pyramids were constructed of different types of limestone and granite. The main quarry for
limestone was located in Giza, and this local stone was used for much of the construction. However,
higher quality limestone for the outer casing of the pyramids was taken from Turah on the east side
of the Nile Valley. Granite was quarried from Aswan, 934 km south, and brought by boat to Giza.
A modern photograph of the pyramids at Giza is shown in Figure 6.
To cut the limestone, the Egyptians used tools of wood, stone and copper. A typical core block of
limestone for a pyramid was about 1 cubic meter in volume, weighing 2.5 metric tons (Lehner,
1998, pp. 224-225), although some stones at the pyramid base were much larger and others, near the
top, were somewhat smaller. Workers had to cut channels into the stone wall of the quarry all
around the desired block, and then use a giant wooden lever to break it free and pry it out. Sockets
for these levers are still visible in the quarry walls, illustrating the size of the levers needed. For
quarrying granite, which is harder than limestone, workers used tools made of dolerite, a very hard
rock. Workers then loaded the stone block on a sled and pulled it with ropes along a smooth, hard
hauling track to its destination, with other workers pouring a lubricant, such as water, just in front of
the sled to reduce friction. Upon reaching the construction site, workers had to haul the stone up
ramps to reach the desired location on the pyramid. Mortar made by heating gypsum in a kiln was
then mixed with water and applied to the stone surface, and the stone was set into place. The
invention of the wheel, occurring as early as 5000 BCE in the Tigris-Euphrates Valley (Tunis, 1955,
p. 9), had not reached Egypt in time for construction of the pyramids at Giza.
Let us consider the resources needed for this operation. Wood was used to make the quarry levers,
sleds, hauling tracks, and ramps. Wood was also used as fuel in smelting ores to make copper and
bronze, and for making mortar. There were additional uses of wood, such as for shoring of
underground mine shafts and for constructing the buildings of the metalworking industries. Of
particular interest, wood was needed to make the boats that hauled granite from Aswan to Giza.
Some of the wood used in constructing the boats had to be imported from Lebanon where large,
sturdy cedars were available. Because of their expense and scarcity, cedar timbers were stitched
together with rope so they could be taken apart and re-used. And when the cedar timbers reached
the end of their useful life as boating material, they were used to make sleds.
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Figure 6. The pyramids at Giza, Egypt. These pyramids were constructed in the mid-third
millennium BCE. Photo accessed September 2008 at:
http://en.wikipedia.org/wiki/Image:All_Gizah_Pyramids.jpg. Photo taken by Ricardo Liberato in
June 2006, licensed by Creative Commons Attribution ShareAlike 2.0 at:
http://creativecommons.org/licenses/by-sa/2.0/.
Copper, arsenic, and tin were used to make copper and bronze tools for quarrying stone and making
other tools of construction. Limestone was used not only as construction material for the pyramids
but also for the hauling tracks: wooden timbers were positioned as bedding and then a layer of
limestone chips mixed with mortar was applied over the timbers to make solid hauling tracks as
wide as 11 meters at some locations (Lehner, 1998, pp. 202-203). Clay was used to make pottery for
carrying water for the mortar and also for lubricating the hauling tracks.
None of this includes the resources needed to feed and house the workers. There were roughly
20,000 to 30,000 workers at Giza at any one time during construction of the pyramid of Khufu
(Lehner, 1998, pp. 224-225). Construction lasted on the order of 20 years, considering that the
pyramid consists of roughly 2.3 million stone blocks, each of which had to be quarried, transported
to the site, and lifted into place.
Some of the earliest known graffiti is found on Menkaures pyramid temple written around 2500
BCE. The graffiti in heiroglyphics identifies the names of two construction gangs working on the
pyramid; each gang had roughly 1000 workers. The two gangs together constituted a construction
crew of 2000. The symbols found in the graffiti are shown in Figure 7.
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Figure 7. Egyptian hieroglyphics for Friends of Menkaure (top) and Drunkards of Menkaure
(bottom). These were two pyramid construction gangs who left their names in graffiti in
Menkaures pyramid temple around 2500 BCE (redrawn based on Lehner, 1998, pp. 224-225).
The years of the pyramid construction at Giza were highly productive in Egypt. Food was abundant,
the population grew, and progress was made in developing arts and language. When the Neolithic
Wet Period ended and the drought began around 2200 BCE, the Nile no longer flooded annually,
causing fluctuations in agricultural output. The Egyptians experienced food shortages, and the
population declined. These hardships are reflected in the biblical passage where Joseph interprets
the Pharaohs dream as an omen of upcoming famine, warning the Pharaoh to store large amounts
of grain (Hughes, 2001, pp. 39-41; Genesis 41:1-37, Old Testament).
Unlike the Sumerians and several other civilizations, however, whose agricultural systems collapsed
and caused the end of their civilizations, the Egyptians were able to continue producing food. The
second millennium BCE in Egypt included times of plenty interspersed with times of want, but the
civilization continued. Pyramids were built and pharaohs were celebrated. Among the most famous
of the pharaohs was Tutankhamen who died in 1324 BCE. When the heavily fortified tomb of
Tutankhamen was opened in 1922, archaeologists found a solid-gold casket of more than 100
kilograms as well as numerous other gold artifacts, showing the tremendous wealth of the pharaohs
(Lucas and Harris, 1999, pp. 340-348). This wealth made Egypt the envy of many other
civilizations around the eastern Mediterranean. Figure 8 shows the gold funeral mask from
Tutankhamens tomb.
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Figure 8. Gold funeral mask that was placed over the head and shoulders of Tutankhamens
mummy, currently on display at the Cairo Museum. Accessed September 2008 at:
http://www.egyptarchive.co.uk/html/cairo_museum_54.html. Photo by Jon Bodsworth in
December 2007, with reproduction details at: http://en.wikipedia.org/wiki/Image:Tutmask.jpg.
Resources, especially wood, continued to be used in great quantities. Besides metalworking,
considerable amounts of wood were used as fuel for the rapidly growing production of glass. The
use of silica (e.g., sand) to make glass in Egypt dates back to around 1500 BCE (McGovern et al.,
1993). Glass vessels were especially popular. Various minerals were added to produce color in the
glass; recent analysis of the soda content (sodium carbonate) and lime content (calcium oxide) of
the ancient glass shows that workers had a good understanding of the glass-making process.
The period beginning in 1200 BCE and lasting more than three centuries was noteworthy in that a
second severe drought influenced Egypt and the entire eastern Mediterranean (Bell, 1971). But
unlike the earlier drought in 2200 BCE, this dry spell coupled with continuing environmental
exploitation resulted in a large scale economic collapse (Chew, 2007, pp. 79-84). The ensuing
economic dark age is discussed in more detail in the next section. Following the collapse, Egypt
was conquered several times in the first millennium BCE although it managed to retain many of its
customs and activities even while under foreign control (Hughes, 2001. pp. 79-84). During one of
these occupations, Egypt was under domination of Greece, and was subjected to laws that put
logging under state control (Deacon, 1999; Thirgood, 1981, p. 43).
The ancient Egyptian civilization ended in 30 BCE when Egypt became a province of the Roman
Empire. Although still productive, the country had changed compared with three millennia earlier.
Deforestation was severe, especially since the Egyptians grazed their domesticated animals on land
cleared of wood, guaranteeing that any new growth of seedlings would be immediately eaten. The
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trees in Egypt were not large even in ancient times; the quantity of cedar imported from Lebanon
attests to the need for larger timbers for the elaborate construction. But imports were also limited at
times: in the middle 1600s BCE, the tradition of burials in large sarcophagi made of imported
Lebanon cedar was replaced by burials in much smaller coffins of local sycamore, due to the
scarcity of high quality imported wood (Bell, 1975). Large game such as elephant, rhinoceros,
giraffe, and gerenuk gazelle were rare or missing in the northern part of the country, and the wild
camel was extinct (Hughes, 2001, pp. 39-41). Natural vegetation in the Nile Valley had been largely
replaced by land cultivated with crops for human consumption and land for grazing domesticated
animals. Although the Egyptians understood the importance of natural cycles as their livelihood
revolved around the annual flooding of the Nile, their appreciation for the critical role of
ecosystems in preventing desertification was absent. Many historians have written about natural
changes in climate over the three millennia of ancient Egypt, and certainly these changes played a
role. But the impact of the civilization on the functioning of natural systems even in these early
times was also significant.
2.4. Ancient Greece, 1400 BCE 300 BCE
2.4.1 Mycenaea and the Dark Age that Followed
While the early Egyptian pyramids were being constructed, the Minoan culture was developing on
the island of Crete. The Minoans had a thriving economy by 2200 BCE, with highly productive
mining and agriculture, and with many large palaces and other buildings. However, battles with a
growing population on the Greek mainland, the Mycenaeans, eventually led to their downfall in
around 1400 BCE. It was at this time that the Mycenaeans developed the first great civilization in
ancient Greece.
The Greek kingdoms under the domination of the Mycenaeans during 1400-1100 BCE further
developed use of the earths resources, especially stone, metals, wood, and land. Entry into the
massive walled city of Mycenae was through the Lions Gate, named for its stone sculptures
shown in Figure 9. Roads of stone were built into the countryside. Craftsmen made clay pottery as
well as ornaments of ivory and gold. Rich deposits of tin from what is now Cornwall in Britain
were mined and imported to Greece for making bronze (Wertime, 1973). Land was intensively
farmed as the population grew. The civilization is perhaps best remembered for their legendary war
against the city of Troy around 1200 BCE. The story of the Trojan War was described in The Iliad
by Homer around 800 BCE, and then continued in The Aeneid written by Virgil in 19 BCE
(Massachusetts Institute of Technology, 2010a). According to The Aeneid, Mycenaean soldiers hid
inside a large wooden horse which the Trojans brought inside their gates, unthinkingly accepting it
as a gift, only to be conquered by the soldiers once inside the city. This is one of many battle
stories; it is clear that wars as well as agriculture and works of art consumed significant quantities of
natural resources at this time.
Iron smelting was discovered in the eastern Mediterranean region around 1400-1300 BCE
(Liebowitz and Falk, 1984), and became significant in the area by 1200 BCE. The latter date is
considered by many historians to mark the end of the Bronze Age and the beginning of the Iron Age
in this part of the world. The discovery of iron was to play an important role in ancient Greece
centuries later. The location of the earliest ironwork is unknown, but it may have been in Cyprus,
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where steel knife blades from the twelfth or eleventh centuries BCE have been excavated, or in
Northern Anatolia along the Black Sea (Sass, 1998, pp. 86-93).
Figure 9. Lions Gate at the entrance to Mycenae, showing the sculptures of two lions above the
entrance. Accessed September 2008 at: http://en.wikipedia.org/wiki/Image:Lions-GateMycenae.jpg. Photo taken by Andreas Trepte in July 2008, licensed by Creative Commons
Attribution ShareAlike 2.5 at: http://creativecommons.org/licenses/by-sa/2.5/.
Of high importance at the end of the Bronze Age was the drought that struck Egypt and the entire
eastern Mediterranean. The economic collapse occurring at this time was the result of the drought
plus multiple additional stresses, such as deforestation, erosion of agricultural soils, constant
internal wars among the communities in Greece and elsewhere within the region, and ultimately
attacks by outsiders from the North noting weaknesses in the ability of the Mediterranean states to
defend themselves (Chew, 2007, pp. 79-84). Historians have long debated the relative importance of
these and other factors that led to the collapse. But the effects are clear: the downfall brought an end
to international trade. It was thus impossible to import tin from Cornwall to make bronze for
weapons or for the tools of agriculture. The drought coupled with soil erosion and other factors
caused crop yields to plummet, resulting in poverty and hunger for thousands. It is estimated that
more than three-quarters of the Mycenaean population perished. With attacks from outside invaders
continuing, the shortage of bronze even forced metalworkers to recycle bronze religious vessels to
make weapons.
The resulting economic dark age lasted for several centuries. Collapse of the urban infrastructure
meant that cities could no longer support the food, water, and energy needs of large urban
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populations, so people mainly lived in small communities. This was the beginning of a new social
structure that eventually led to the rise of the Greek City-States.
It was also during this dark period that innovations in smelting iron were developed, which many
historians attribute to the shortage of bronze. The creation of stronger iron farming tools opened
new areas for agriculture, e.g., areas of heavy clay soil previously unused, so that people did not
have to rely on the eroded and depleted soils of the Mycenaean era farms (Chew, 2007, pp. 104106). When the drought began to ease around 800 BCE, economic recovery started and a new
period of human progress began.
2.4.2 The Greek City-States
Lifestyles improved and the population grew over the period 800 BCE to 600 BCE. Conquests
began again, as Greece colonized lands around the Mediterranean to obtain resources such as
cropland, grazing land, metals, and especially forests. Forested land in Greece, which had recovered
somewhat from deforestation during the second millennium, was again exposed to logging.
Roughly one million acres of woodland were needed for a single metallurgical center at this time.
Additional timber for construction of grandiose public buildings came from locations around the
Mediterranean and from Asia as far away as India. Environmental degradation also occurred with
the discovery of silver in the late sixth century at Laurion near Athens, which led to silver mining
and smelting that employed over 11,000 workers. The wealth resulting from these silver operations
was instrumental in supporting the Athens navy which boasted several hundred ships (Chew, 2001,
pp. 64-72; Thirgood, 1981, p. 56; Sass, 1998, pp. 72-78).
Trade also increased markedly. Attica, the region of Greece containing Athens, imported 75% of its
food, mainly from Egypt, Sicily, and Italy. Both imports and exports of material goods of all kinds
were big business in Athens; total annual trade volume exceeded the equivalent of several million
current US dollars by the fifth century BCE. Greek industries exported metal weaponry, woolens,
leather, and pottery (Chew, 2001, pp. 64-72).
Dramatic changes in the relative prices of metals reflect better metalworking technology as well as
improving economic conditions. In the nineteenth century BCE, 40 ounces of silver bought one
ounce of iron. By the seventh century BCE, one ounce of silver bought 2000 ounces of iron, a
decrease in the relative value of iron by a factor of 80,000 (Sass, 1998, pp. 86-93).
While the Greeks were moving into new areas, Persia had grown to become one of the largest
empires in history, with land stretching from Pakistan to the Balkan peninsula by the late sixth
century BCE. In 490 BCE, Persia attacked Athens in the Battle of Marathon, of historical
importance because the stronger metal armor of the Athenians helped them win over a much larger
force of Persians. Many additional battles followed, and the Greek city-states ultimately defeated
Persia. Athens became a formidable sea power, with its colonies spreading from the Balkan
peninsula to include regions in Spain and France, parts of Italy, coastal areas on the Black Sea, the
eastern shore of the Mediterranean, and parts of northern Africa.
Pericles came to power in the 450s BCE and brought new heights to civilization in Athens. An
advanced government with representation by both rich and poor was developed. Daily life was
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dominated by agriculture and craftsmanship, with the farmlands supporting an urban population
over 100,000. The apartments and other buildings of Athens were densely packed and were located
within a distance of 1.6 km surrounding the Acropolis at the city center (Hughes, 2001, p. 61). The
buildings of the Acropolis were constructed of marble; the main building, the Parthenon, contained
a large statue of Athena in gold and ivory. A recent photo of the Parthenon is shown in Figure 10.
The original gold and ivory statue of Athena has been lost, but a copy made in marble in the first
century BCE by Antiochos of Rome has survived as shown in Figure 11.
Figure 10. The western side of the Parthenon in Athens. Accessed September 2008 at:
http://en.wikipedia.org/wiki/Image:Acropolis_of_Athens_01361.jpg. Photo taken by Glen Larson
in February 2006, and it is in the public domain.
The Greek city-states issued their own individual coins around this time. The worlds first coins
were made of a gold-silver mix known as electrum in Lydia in the seventh century BCE, but they
were only used for storage and transport of wealth. The first coins for daily transactions appeared
two centuries later in Athens. An example of one of these earliest coins is shown in Figure 12, a
silver coin known as a tetradrachm, or four drachms, used after 449 BCE. The obverse shows the
helmeted head of Athena, while the reverse shows the owl, a symbol of Athens, with an olive sprig
and a crescent above it. This coin had a mass of 16.85 grams, and was slightly smaller than a U.S.
half dollar coin. The salary of a typical unskilled worker at this time was about 1/3 drachm per day,
while a professional such as an architect earned about one drachm per day (Sass, 1998, pp. 72-78).
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Figure 11. A marble copy of the original gold and ivory statue of Athena that stood in the
Parthenon, attributed to the fifth century BC sculptor Phidias. This replicate statue was made in the
first century BC and is signed by Antiochus of Rome. Accessed September 2008 at:
http://en.wikipedia.org/wiki/Image:Athena_Parthenos_Altemps_Inv8622.jpg#file. Photo taken by
Marie-Lan Nguyen in September 2006, and it is in the public domain.
Figure 12. The silver tetradrachm coin used in the fifth century BCE in Athens. Accessed
September 2008 at http://commons.wikimedia.org/wiki/Image:SNGCop_039.jpg#file. Photo is
licensed by Creative Commons Attribution ShareAlike 2.5 at:
http://creativecommons.org/licenses/by-sa/2.5/.
Between metalworking, public bathhouses, bakeries, residential heating and cooking, and other
operations involving the need for heating, Athenians had an insatiable demand for wood and
charcoal as an energy source (Olson, 1991). Many free men without any other opportunities could
find work cutting wood in the forests and/or carrying it into the city. Others built pits or mounds in
the forests on which to make charcoal, which could be more efficiently brought to the city. Both
wood and charcoal brought to Athens were sold to wholesalers, who in turn sold these materials at a
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profit to retailers. Retailers then sold smaller quantities in the marketplace to individuals and
businesses, again at a profit.
It is no surprise that deforestation became a serious problem. As in ancient Egypt, once trees were
cut, the land was used for grazing livestock which prevented re-growth of the trees. These practices
led to serious economic disruptions and later contributed to the decline of Athens and other Greek
city-states.
Athens was not the only city-state with over 100,000 inhabitants; Corinth and Syracuse also had
such large populations. Given the size of these cities, the ancient Greeks obviously needed to be
concerned about waste disposal. Archaeological finds indicate that networks of sewers carried
stormwater as well as residential wastewater, and any other waste left in the streets, out of the city
and in some cases out to sea. However, the limited data available make it difficult to know details of
waste disposal, such as how much was disposed on land and how much in bodies of water.
Nevertheless, it is clear that waste disposal in the ocean, even massive amounts of waste disposal,
was considered acceptable practice (Lindenlauf, 2003).
One can obtain more insight into the environmental attitudes of the ancient Greeks by considering
writings of the leading philosophers of the day. For example, the Greek philosopher Protagoras is
well-known for his statement Man is the measure of all things. Yet many artists and philosophers
at this time believed in the importance of the natural world, with some artists imitating nature in
their artwork.
The Greek philosopher Plato, 429-347 BC, wrote in some detail of the deforestation around Athens
(Massachusetts Institute of Technology, 2010b). He also wrote of laws applicable to certain holy
areas in Greek forests where setting fires and removing wood and leaf fodder were illegal,
punishable by fines. More generally, Plato wrote about the dangers of becoming too dependent on
material goods, noting that such dependency can lead to resource wars, and wrote of the unity
between the microcosm of human life and greater order of the universe (Massachusetts Institute of
Technology, 2010c; Stanford University, 2010). One of Platos students at the Academy was
Aristotle, 384-322 BC, who developed lectures and writings in many disciplines that have
influenced scientific and philosophical discourse up to the present day. For example, in his written
piece Politics, Aristotle discussed three categories of wealth (Massachusetts Institute of
Technology, 2010d). The first category is the natural economy which includes growing crops,
tending herds of livestock, hunting, and the like, where plants and animals are reproducing
naturally, and whose products have intrinsic value. The second category is the unnatural economy
which includes retail trade, or wealth gained merely by exchange and taking profit. Aristotle noted
that in this second category, people are merely extracting riches from each other rather than
engaging in an activity that converts a natural resource into a product with value. The third
category is partly natural, and this includes extractive industries such as mining. For example,
producing a metal from ore makes use of a natural resource which is converted to an object with
value. However, the resource is not growing or reproducing and yet it is being sold for profit.
Aristotle recognized this problem, and was thus one of the earliest writers to distinguish between
renewable and non-renewable resources.
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Aristotle also developed a sophisticated classification of animals based on careful observation of
their physiologies (University of California, Berkeley, 2010). He was able to explain the earths
hydrologic cycle, and wrote about changes in the continents and oceans over geological time scales.
Much of what we know about the biosphere today, which plays a role in modern discussions on
sustainable human development, had its beginnings in Aristotles original work.
Xenophon, a contemporary of Plato and Aristotle, traveled extensively in Persia and described his
observations there. The Persian king judged his local governors by the care they gave to the land:
governors with productive farms and forests were rewarded, while those whose lands could no
longer provide for the inhabitants were punished. Although such policies were not successful in
preventing abuse of the land in Persia, Xenophon recognized their value to the Athenians as he
wrote his book Oeconomicus (Hughes, 2001, p. 59-62).
Despite the wisdom of its philosophers, the decision makers in Athens did not pursue a sustainable
trajectory. When its local forests were used up, the Athenians took over forested land further away,
continuing to exploit resources without concern for their natural replenishment. Erosion in
deforested areas became a serious problem, creating marshes where malaria-bearing mosquitoes
bred (Chew, 2001, pp. 64-72). Agriculture declined as soils became depleted, and food had to be
brought in from further away. Ultimately, the civilization could no longer support itself. It was
replaced by another great civilization which we now consider.
2.5. Ancient Rome, 500 BCE to 500 CE
2.5.1 The Roman Republic
During the first half of the thousand-year period of Romes domination in the western world, the
Republic grew from a collection of small villages in the years prior to 575 BCE (Sinnigen and
Boak, 1977, p. 38) to the biggest city the world had ever known with more than 1 million people by
the first century BCE (Wells, 1984, p. 213; Aldrete, 2007, p. 78). It was also during this period that
the Republic expanded its influence from central Italy to include virtually all of Spain, France, Italy,
the Balkan peninsula, the eastern coastline of the Mediterranean, and parts of northern Africa.
One major difference between ancient Rome and ancient Greece is that the Greek city-states were
politically independent. They often fought each other over resources, which of course were never
sufficiently plentiful to satisfy those in power. Combined with the possibility of attacks by
outsiders, even powerful Athens had to be vigilant. In contrast, many foreign lands conquered by
the Romans, after experiencing brutal wars waged by the Roman military, had long periods of peace
and prosperity. Although battles continued, they were mainly confined to the frontiers. It is this
prosperity that enabled great progress in human civilization during this era.
Extensive use of resources made the Roman expansion possible. The Romans had access to iron
mines when they took over Etruria in central Italy in the third century BCE (Sinnigen and Boak,
1977, p. 24 and p. 54), and they used iron from that area and other locations such as Noricum,
modern-day Austria, and the island of Elba to make steel weapons that could not be matched (Sass,
1998, pp. 74-78 and p. 96). For example, it is said that the wrought iron swords of the Gauls bent
during battle and even helmets could be cut by Roman legions armed with steel bladed swords.
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Metalworking for other purposes employed iron, lead, copper, bronze, silver and gold. Roman
engineers cut stones and used them to construct thousands of kilometers of roads stretching
throughout the Republic. The most famous of these, the Appian Way shown in Figure 13, was built
near the end of the fourth century BCE. Roman engineers also built a network of aqueducts to
supply the city of Rome and many other cities around the Republic.
Land resources were of special importance. Land subject to tax or rent in some provinces was
categorized by its fertility. In Pannonia, for example, categories were first class land, second class
land, a meadow, an acorn-bearing wood, a shared wood, and pastureland (Campbell, 1996, pp. 7479). Land in the flood plain of rivers was problematic. Settlers needed to live near fresh water, but
there was danger of flooding. Different provinces addressed this problem in different ways, e.g., by
allocating taxable land only outside the area of the greatest known flood. In some cases, officials
allocated land to individuals that included flood plains due to scarcity of land; obviously this caused
disputes and occasionally legal actions.
Figure 13. The Appian Way near Rome. Accessed September 2008 at:
http://en.wikipedia.org/wiki/Image:ViaAppia.jpg#file. Photo taken by Paul Vlaar in June 2003.
Licensed under GNU Free Documentation License version 1.2 available at:
http://commons.wikimedia.org/wiki/Commons:GNU_Free_Documentation_License.
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Forestland was valuable since wood was needed for many purposes: to build ships for the Roman
Navy, to construct buildings, and as energy for industry and domestic needs. The resulting
deforestation is known to have contributed to erosion of forest soil and flooding of the Tiber River
in Rome, which was unfortunately commonplace. Eventually much of the Roman Republic, from
Morocco and other parts of North Africa, to Spain and France, as well as Italy and areas further
east, had large areas of deforestation (Chew, 2007, pp. 92-93).
In the later years of the Republic, resources were used for extravagant lifestyles of the upper classes
(Sinnigen and Boak, 1977, p. 240). Homes of the rich were adorned with marble columns, statues,
paintings, silverware, tapestries, furniture of rare wood, and antiques from Greece. Many of the
wealthiest also had second homes in the country, similarly decorated. In contrast, most of the rest
of the population of Rome lived at a subsistence level, barely able to pay for rent and food.
Inequities between the rich and poor as well as jealousies over power and widespread corruption
eventually plunged Rome into civil war. The Roman Republic officially ended in 27 BCE when
Augustus, the grandnephew of Julius Caesar, was proclaimed emperor.
2.5.2 The Roman Empire
Emperor Augustus led a massive construction program to improve the infrastructure of Rome
(Wells, 1984, pp. 85-87). He constructed numerous public buildings, including the Senate House,
and restored the Capitol and major theaters as well as temples throughout the city. He greatly
expanded the capacity of the aqueducts which ultimately had the potential to deliver somewhere
between 322,000 and 1.01 million m3 of water per day (Dodge, 2000, p. 185). The opening of
additional quarries at Carrara, first developed by Julius Caesar, enabled extensive use of marble.
Indeed, Suetonius (Sinnigen and Boak, 1977, p. 555) wrote that Augustus boasted he found Rome
built of brick and left it built of marble (Aldrete, 2007, p. 112). Crafts also thrived at this time. For
example, glassblowing was developed by the Phoenicians, and Rome soon became a major center
for making vessels and other glasswork including window glass (Trentinella, 2003).
The construction boom continued well after Augustuss death in 14 CE. One of the greatest
developments advancing construction in Rome, and eventually throughout the world, was the
invention of concrete (Sass, 1998, pp. 127-133). The Romans first used ancient technology of
heating chalk and seashells to temperatures above 900oC to form lime, which was then mixed with
volcanic ash to make cement. They discovered that a particular type of volcanic ash found locally,
pozzulana, made improved cement that set even under water. At first, this cement was used as
mortar for bricks and stones. But eventually Roman engineers came up with the idea of mixing
cement, broken rocks, and sand together to form a substance that could be poured into place using
wood forms; thus did the discovery of concrete revolutionize the building industry.
Two of the most well-known construction projects built around the first century CE are a Roman
aqueduct whose most famous section is the Pont du Gard near Nimes, France, and the Colosseum
with seating for over 50,000 spectators in Rome. Both were built of stone, shown in Figures 14 and
15, respectively.
Rome continued to expand in the first and second centuries CE. Maps of the Roman Republic in 44
BCE and the Roman Empire in 117 AD are shown in Figures 16 and 17. The Empire acquired
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Dacia (present-day Romania) with its abundant gold resources as well as Mesopotamia with its
fertile soil. Much of England and parts of Scotland and Wales fell under Roman rule, giving the
Empire access to coal as a source of energy. Almost all of the surface outcroppings of coalfields in
England were worked by the Romans by the end of the second century (Smith, 1997). A complex
system of irrigation was set up for crop production in the desert areas of North Africa.
Figure 14. The Pont du Gard Aqueduct in southern France. Accessed October 2008 at:
http://commons.wikimedia.org/wiki/Image:Pontdugard.jpg. Photograph is in the public domain.
Figure 15. The Colosseum in ancient Rome. Accessed September 2008 at:
http://en.wikipedia.org/wiki/Image:Colosseum_in_Rome-April_2007-1-_copie_2B.jpg. Photo taken
by David Illif in April 2007, licensed by Creative Commons Attribution ShareAlike 2.5 at:
http://creativecommons.org/licenses/by-sa/2.5/.
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Figure 16. The Roman Republic in 44 BCE. Accessed September 2008 at:
http://commons.wikimedia.org/wiki/Image:Roman_Republic-44BC.png#file. Licensed under GNU
Free Documentation License version 1.2 available at:
http://commons.wikimedia.org/wiki/Commons:GNU_Free_Documentation_License.
Figure 17. The Roman Empire in 117 AD. Accessed September 2008 at:
http://commons.wikimedia.org/wiki/Image:Roman_Empire-117AD.png#file. Licensed under GNU
Free Documentation License version 1.2 available at:
http://commons.wikimedia.org/wiki/Commons:GNU_Free_Documentation_License.
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The needs of a city of 1 million were difficult to satisfy without modern technology, and especially
without fossil fuels. Water was originally provided by wells throughout the city (Dodge, 2000,
p.185), but population growth as early as the second century BCE demanded construction of
aqueducts. Extensive distribution systems were also needed to deliver the water to residents. The
prolific Roman writer Pliny the Elder stated that in 33 BCE, Agrippa, the Roman General, built 500
ornamental fountains as well as 700 basins and pools where residents could obtain water for their
domestic needs. This required other resources, such as large quantities of lead for making pipes.
The number of basins and pools increased substantially after the Empire was established: 11 major
aqueducts fed the city by the early third century CE. They were true engineering feats, the longest
being the 91-kilometer Aqua Marcia built during 144-140 BCE. The average slope of 2.7 meters per
kilometer allowed water flow by gravity from the springs at its source into the heart of Rome. To
maintain a slight negative slope in complex topography, the Aqua Marcia included tunnels through
mountainous areas as well as arcades (similar to those in Figure 14) where the water flowed high
above valley floors. The cost of constructing this aqueduct was likely covered by booty obtained
from sacking the cities of Carthage and Corinth in 146 BCE.
The huge amounts of water entering Rome also had to be drained, especially considering that the
aqueducts were flowing 24 hours per day and that much of Rome was originally marshland.
Drainage of wastewater required an enormous system of sewers that had most their inlets on the city
streets and outlets at the Tiber River. The most famous of these is the 1.6 kilometer long Cloaca
Maxima, an underground tunnel up to 4 m high and 3 m wide built several centuries before
Augustus. Pliny wrote that Agrippa traveled the underground sewer system boat by to inspect it in
33 BCE (Dodge, 2000, p. 193; Aldrete, 2007, pp. 170-171).
City officials had a challenge to ensure that Rome was adequately supplied by fresh water at all
times and that the risk of flooding was minimal. However, an even more problematic task was
ensuring sufficient food. Unlike water transport and distribution which was publicly funded,
shipping of food was provided by private companies. To ensure adequate food for the citys poor,
officials distributed a dole to qualifying poverty-level Romans, numbering around 25% of the
population in the early years of the Empire. The others bought their food in the marketplace, and
there the government provided subsidies to keep the prices reasonable. Several authors have
estimated amounts of food consumed annually by each Roman; recent estimates are 237 kg of
wheat, 20 liters of olive oil, and 100 liters of wine (Mattingly and Aldrete, 2000). There were also
other grains such as barley as well as fruits and vegetables available in season, and the well-to-do
had meat and fish in addition. The great majority of this food was brought by ship and delivered to
the ports on the Mediterranean near Rome. To provide these quantities, an average of 17 ships per
day must have brought food during the roughly 100-day shipping season, and some 3,000 porters
working nine-hour days would be needed to unload the ships in the limited harbor space. Massive
areas for storing food were also built. Shipment from abroad was clearly essential for survival of the
city: it is noted that the grain yields in Egypt under control of the Romans were ten times greater
than those in Italy. The Roman province of North Africa, west of Egypt, exported enough grain to
feed 350,000 people for one year (Chew, 2001, p. 92; Hopkins, 1978).
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Accounting for spoilage, extra food stockpiles in case of famine, exotic foods for the wealthy, and
accidents or storms encountered by the ships, these numbers are almost certainly lower limits.
Historical accounts from the city show that famines were always a possibility, and in fact several
famines were recorded throughout the Roman era (Sinnigen and Boak, 1977, p. 278). Furthermore,
the quantities do not account for feeding the Roman Army, which varied in the range 300,000400,000 men (Garnsey and Saller, 1987, pp. 88-89).
It is noteworthy that olive oil was transported in thick-walled ceramic amphorae, which themselves
comprise a considerable volume. The Romans discarded their amphorae at a site where ceramic
empties now tower 35 meters high over an area of 20,000 square meters; the site contains some
53 million discarded vessels. In the later years of the Empire, a portion of these wastes were used as
construction material to lighten architectural vaulting (Mattingly and Aldrete, 2000, p. 148).
An additional staple, wood, must be considered as necessary for a number of purposes. Used as a
fuel, wood provided the energy for manufacturing consumer products for the Romans, but it became
increasingly scarce as time passed. By the second half of the first century CE, ceramic factories
near Rome in Etruria were declining due to shortages of wood while new factories were built in the
heavily forested areas of southern France (Perlin, 1989, pp. 121-128). Glass factories and iron
smelting in Italy were also relocated to southern France. All three of these industries in France were
in decline again by the end of the second century, moving northward in search of more wood. Silver
smelting in Iberia declined in the second century CE due to wood shortages after the 400 years of
operation there had denuded some 7000 square miles (1.8 million hectares) of forest containing 500
million trees. Similarly, Roman copper production on Cyprus depended on local forests which had
regenerated themselves during the economic dark age that began in 1200 BCE. But the second time
around, the local rulers on Cyprus were careful to prevent wholesale destruction of their woodlands.
Nevertheless, nearly 500 million trees were cut down on the island for copper smelting during the
last century BCE and first few centuries CE.
Wood use for domestic purposes within Rome was also significant. Recent research with a standing
Roman villa in Germany has provided estimates that the central heating system for a typical villa of
the wealthy in Rome consumed some 286 pounds (130 kg) of wood per hour, over two cords of
wood per day. Other research has shown that a small private bath of the type used in Rome
consumed 114 tons (104 metric tones) of wood annually. The public baths, much larger, consumed
considerably more: beginning in the first century CE, the baths became a regular place to
congregate daily after work. Ultimately, over 900 public baths were constructed within Rome for
the pleasure of its residents, the largest holding 2000 bathers at a time. These baths used such great
amounts of wood that specially designated forests in Italy were reserved for their use. When these
were depleted in the fourth century CE, ships were dispatched to the province of North Africa to
obtain wood so the baths could keep running (Perlin, 1989, pp. 112-119 and 121-128).
Conservation of energy became important in the latter years of the Empire. As wood shortages
increased the price of glass in Rome, the poor of the city realized there was money to be made. So
they collected broken glass from around the city and sold it to artisans for recycling, a process
which used much less energy than manufacturing glass with raw materials. Roman architects
realized the benefit of south-facing windows to reduce the amounts of fuel needed for heating, and
this concept was used in homes as well as public and private baths. But the availability of wood
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continued to decline, and eventually citizens resorted to collecting anything that would burn for
their cooking and heating.
Entertainment of the Romans also took its toll on the environment. To deflect worries about the
declining economy and famines, Roman rulers had continual events in the Colosseum and other
arenas. Among the most popular were contests and mock hunts with wild animals imported from
Africa and elsewhere. Tens of thousands of animals were brought to Rome and killed for spectators.
But as large as these numbers were, the loss of wildlife due to destruction of natural habitats for the
expansion of agriculture was far more significant in the long run (Hughes, 2001, p. 74; Shaw, 1981,
p. 382).
Although some writings from ancient Rome show an awareness of the danger in abusing the
environment, works of the most prolific writers do not show an effort to comprehend the natural
world as a whole, nor is science emphasized as a guide to understanding nature. Thus these writers
were not likely to have understood the importance of protecting the environment from exploitation.
This was true, for example, of the writings of the geographer Strabo (64 BCE 24 CE) and the
astronomer Ptolemy (second century CE), both of whom wrote detailed descriptions of the known
world at that time, and of Pliny in the first century CE who wrote the famous work Natural History.
Furthermore, by the third century CE, Roman philosophy based on mysticism rather than science
was gaining favor (Bowler, 1992, pp. 54-56). Thus the written record from ancient Rome shows
little evidence of any resistance to the massive environmental damage caused by the Empire.
Ultimately, the Romans were better at conquering far-away lands than they were at governing these
lands with their different cultures and traditions. Furthermore, the limitations of the pre-industrial
world prevented rapid advancement of technology, and hence economic growth could not be
sustained. By the late second century CE, the economy was in serious trouble: the lack of ability to
control the sprawling Empire was taking its toll. Food shortages became widespread, and
infrastructure fell into disrepair. Civil wars erupted throughout the Empire. Commercial enterprises
reverted to the barter system as the economy faltered. Heroic attempts by emperors in the third and
fourth centuries CE provided temporary stability, and the capital of the Empire was moved to
Constantinople (present-day Istanbul) in 330 CE. But eventually the strains of trying to rule an
empire of 60 Million people from a single headquarters failed. In 395 CE, the Roman Empire split
into two halves. The eastern half became the Byzantine Empire while the western half struggled for
a while but ultimately dissolved into numerous small kingdoms when Rome was captured by the
Goths in 476. The rise and fall of Rome is apparent in Figure 18 showing the population of the city
as a function of time through the years of the Republic, the Empire, and beyond.
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Figure 18. Population of Rome from 600 BCE to present. Y-axis shows population of the city in
thousands (Data taken from Aldrete, 2007, p. 78, Chew, 2007, p. 152, and Wolfram, 1990).
2.6 The Dark Ages and Middle Ages, 500 to 1450
It is impossible to discuss the period following the collapse of Rome without emphasizing the rise
of organized religion. Both halves of the Roman Empire were Christian, and acceptance of
Christianity grew rapidly in the both the East and West after the division. But the religion of Islam
after the death of Muhammed in 632 also grew rapidly from its beginnings in modern day Saudi
Arabia. Unlike multi-god paganism of earlier times, Christianity and Islam taught belief in one God.
Despite this similarity, regions allied with Christianity and regions allied with Islam devoted huge
efforts to fighting each other, exploiting large amounts of natural resources in the process.
The collapse of the central authority of Rome resulted in a power void such that individual farmers,
who were free men owning the land they farmed, could no longer continue. These free men were
forced to give up their farms and their freedom to wealthy landholders for protection from attackers,
and subsequently worked the farms to profit the landholders (Chew, 2007, p. 164). Eventually this
evolved into the feudal system, which expanded in various forms throughout much of Europe.
Much has been written about the two halves of the Roman Empire (e.g., Diehl, 1957; Anderson,
1996; Thomson, 1998). The West had a smaller population, longer borders to defend, and an
economy built on the spoils of conquest rather than productivity. The Byzantine Empire in the East
had a stronger economic base and was better positioned for trade with the Orient. The East also had
well-established cities and common traditions consistent with unification. These factors contributed
to the dissimilar fates of the East and the West following the fall of Rome.
The successes of the Byzantines were intermittent with periods of economic strife, unlike the
relative stability of Rome in previous centuries, but its achievements were notable. The monumental
church Hagia Sofia was completed in 537 and was the largest cathedral in the world for almost a
thousand years (Kleiner and Mamiya, 2008, p. 329). Parts of the cathedral have been rebuilt over
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the centuries (see Figure 19). Emperor Justinian attempted to revive the glories of the Roman
Empire by expanding the Byzantine conquest throughout the Mediterranean region and North
Africa, including land as far as Spain. The population of Constantinople reached 345,000 at this
time (Chew, 2007, p. 152). But the Bubonic Plague in the sixth and seventh centuries, wars through
the next several centuries, and varying exploitation of the environment caused the Byzantine
Empire to rise and fall and then rise again, with Constantinople becoming a major center of
commerce for the eastern Mediterranean and beyond by the tenth and eleventh centuries (Thomson,
1998, p. 81). The classical period of ancient Greece was studied by the Byzantines and it influenced
their art and architecture; these efforts were assisted through earlier translations of ancient Greek
writings by Muslim scholars in the surrounding Arab states who also studied Greek antiquity
(Bowler, 1992, p. 60).
Unlike the East, impoverished conditions dominated the West for hundreds of years, as there were
no leaders strong enough to unify the independent kingdoms. Much of the technology developed by
the Romans, such as efficient farming tools, water distribution systems, and networks of roads fell
into disrepair. Lack of sufficient food plus internal fighting and attacks from outside kept the
population from growing. Scholarship and artistic endeavors were also absent for several hundred
years. One respite to these conditions was a half century beginning in 768 when parts of Europe
were united under Charlemagne.
The rise of Christianity in both East and West influenced the relationship between people and the
environment. Early Christian teachings emphasized that God gave man dominion over the earth so
that nature was to be used for the benefit of humankind. However, it was not permissible to destroy
nature for personal gain. Many common folk reasoned that if God resided in the heavens above the
earth, which was a great distance away, then certainly the earth was open to modification and
improvement by people (Hughes, 2001, p. 84-85). In this interpretation, the spiritual lost out to the
practical. Furthermore, some early Church leaders were influenced by mysticism of the late Roman
Empire and also believed that the true purpose of philosophy was to draw people closer to God; the
study of nature had value only for this goal (Bowler, 1992, pp. 56-62). Later in the Middle Ages, the
study of nature in its own right became more accepted. An increasing number of Church leaders
reconciled the creation as told in Genesis and Aristotles structure of the universe, allowing study of
the natural world as long as the results were interpreted to reflect the divine origin of the world.
Many scholars did, in fact, study the natural world. But there is little evidence in Middle Age
writings that nature was ever appreciated for its life support services. In fact, ecosystem decline
continued and was alleviated only during the economic downturns.
Although the new economic and artistic heights achieved in the Byzantine Empire in the tenth and
eleventh centuries made Constantinople a truly great city (Diehl, 1957, pp. 5-12), Western European
was making remarkable economic gains and achieved commercial superiority over Byzantium
during the eleventh century. In 1095, the Byzantines were attacked by the Seljuk Turks, a powerful
Islamic group, and the emperor appealed to the pope for help. The response organized by the pope
is known as the First Crusade, which attracted 25,000-30,000 people from the kingdoms of the West
to fight for the cause of Christianity. This was the first of many crusades organized by popes over
the next two centuries. During this period, the Byzantine Empire experienced ups and downs, but
overall it lost ground to the rapidly rising Italian dominance of the Eastern Mediterranean
(Thomson, 1998, pp. 93-94). The Empire was in serious economic decline by the thirteenth century.
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In 1453, Constantinople was conquered by the Ottoman Turks, and the last remnant of Byzantine
land became part of the Ottoman Empire.
Figure 19. Hagia Sofia, originally built in the Sixth Century CE. It has been rebuilt several times
since then. Accessed June 2010 at:
http://upload.wikimedia.org/wikipedia/commons/4/4a/Aya_sofya.jpg. Photo taken by Robert
Raderschatt in November 2004. Licensed under GNU Free Documentation License version 1.2
available at: http://commons.wikimedia.org/wiki/Commons:GNU_Free_Documentation_License.
The economic improvements that began in Western Europe in the tenth and eleventh centuries
gained momentum. Food production increased, in part due to the invention of the moldboard plow
and the draft harness for teams of horses. More land was converted to farms to feed the growing
population. There were also fewer battles with invaders. Furthermore, a slight temperature increase
in Europe, sometimes called the Medieval Warm Period, occurred during 980-1450 due to changing
ocean currents in the North Atlantic oscillating over century-long time scales (IPCC, 2001). These
changes contributed to a population increase from 38.5 Million in 1000 to 73.5 Million in 1340.
But as social conditions improved, ecosystems suffered, especially forests. The demand for wood
used for buildings and ships as well as household energy increased. Wood was used to provide
energy for metalworking, which rose dramatically as construction of elaborate buildings such as
huge Gothic Cathedrals began in the twelfth century, and as more swords, armor, and warhorse
accessories were needed. New metal-intensive technologies for war, including guns and cannons,
became available in the 1300s. Hughes (2001, pp. 84-86) notes that deforestation in Europe was
extensive by the year 1300, being about the same as it is today.
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Social structure changed radically in the late Middle Ages as European cities grew and became
centers of commerce rather than primarily centers of political and religious life. Craft guilds were
formed in various professions to protect artisans from what was believed to be unfair competition
and business practices. For example, the wool guild in Florence in the 1330s was said to have
some 30,000 employees in 200 shops (Hughes, 2001, p. 89).
Progress of many types was furthered by the creation of universities in the twelfth and thirteen
centuries. No less than 80 universities were established at this time in Europe, although there was
little interest in studies that would have enabled scholars of the time to recognize the environmental
damage humans were causing. The universities mainly focused on theology and philosophy as well
as law and medicine.
The financial and commercial successes could not continue indefinitely, and Europe entered a dark
period in the early 1300s. Virtually all the arable land had been cultivated by then, and there was
no place to expand farms as the population continued to grow. Marginal land became impossible to
farm due to overuse (Hughes, 2001, pp. 91-92). Then unusually heavy rains hit Germany in 1309
and again in 1315, causing flooding and initiating the first of several famines. Floodwaters damaged
other areas in the following years; for example, the city center in Florence was inundated in 1333, in
part due to deforested land that allowed torrential rains to sweep down the surrounding hillsides.
The famines brought hardship for the first half of the fourteenth century, attributed to short-term
weather extremes, longer-term natural climate change, and uncontrolled human expansion, although
the relative importance of these factors has been debated.
Then Europes financial systems collapsed in the 1340s. Florence had become the banking capitol
of Europe, and rulers had borrowed money to finance their wars. When they could not repay, the
wealthiest families in Florence went bankrupt, and eventually Florence itself declared bankruptcy.
Businesses failed throughout Europe. When a population weakened by famine and economic strife
was hit by a resurgence of the Bubonic Plague in the period 1347-1351, one-quarter to one-third of
Europes population perished. The next eighty years saw seven more epidemics of the Plague.
Despite these terrible hardships, historians point out that the surviving population of Europe
inherited a large wealth per capita that served to bring in the Renaissance. Furthermore, the
economic failures of the 1300s had put commercial and industrial investments at risk, so people
invested in the arts instead (Bowlus, 1980). The fall of medieval Europe thus provided an
opportunity for Europeans to seek different forms of fulfillment and a brief opportunity for the
environment to rejuvenate itself after many years of overuse.
2.7 The Renaissance, Age of Reason, and Enlightenment 1400-1800
The word Renaissance means rebirth which refers to the European discovery of classical Roman
culture and to a lesser extent classical Greek culture. But in fact these cultures had already been
rediscovered in late Middle Age Europe as universities established courses and programs in
classical studies. What changed at this time was attitude toward antiquity and toward the Middle
Ages: the latter time period was not even considered civilized society by Renaissance humanists
(Sider, 2005, pp. 134-135).
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The advances in art, literature, and law which Rome made a thousand years earlier served as a basis
for further development by Europeans. Why did attitudes change so markedly at this time? An
important factor in the rebirth was the unfortunate loss of life by the plague. Those who survived,
especially the peasants, were able to find work more easily than before and had a better standard of
living. More individuals migrated to the cities which helped develop a thriving merchant class.
Furthermore, the common bond of Christianity unified Europe against perceived threats from North
Africa and the Middle East which were dominated by Islam (Bowlus, 1980, pp. xiii-xiv).
Christianity in many sects continued to play an important role in influencing thoughts and activities
of the population. In the late Middle Ages, many Church leaders had adopted the view that the study
of nature could be reconciled with scripture, as nature was a demonstration of Gods handiwork.
The implication was that the natural world should be protected from exploitation. But by the
Renaissance, some authorities in the Church were advocating use of human ingenuity to fully use
the gifts of creation, i.e., natural resources. Bowler (1992, p. 89) writes Reducing Nature to an
essentially material system gave us the means and the right to exploit that system as we wish, under
the assumption that God created it solely for that purpose. People thus had license to use whatever
resources exist, without limit, to further human development.
The Renaissance is perhaps best known for its unparalleled artistic and scientific achievements. The
evolution of these achievements began with humanists putting a major effort into finding and
translating the original texts of the ancient Greek and Roman writings. During the fifteenth century,
these individuals were mainly interested in discovering what the ancients knew rather than moving
beyond that knowledge. But by the sixteenth century, scholars had begun to take advantage of the
science pioneered in ancient Greece to explore the natural world themselves. Books describing
plants, animals, minerals, and other topics in the natural sciences were published, including a
number of treatises by artist-scientist-inventor Leonardo da Vinci (1452-1519). Universities thrived
as scientific discoveries proliferated.
There were many areas of progress. As in previous times of plenty, people had the luxury of
exploring philosophy, science and art. Furthermore, advances in technology allowed more comforts
of life with less labor. Agriculture was enhanced by keeping all land in production rather than
designating certain fields as fallow for a season or more. This was made possible by increasing the
population of livestock to provide manure as fertilizer, and by introducing alfalfa as a legume which
simultaneously provided nitrogen to the soil as well as fodder for the additional farm animals.
Farming efficiency was also improved using cross plowing, or planting along perpendicular lines
to increase the amount of soil exposed to receive seeds (Bowlus, 1980, pp. 210-218).
Johannes Gutenbergs Printing Press in Germany in the mid-fifteenth century, the first press to use
movable type, was one of the most important inventions of the Renaissance. The first book printed
by this method was the Bible, but by the end of the Renaissance there were several thousand print
shops throughout Europe publishing all kinds of works. The average press used 1500 sheets of
paper per day. Because of concern over resource limitations, many printers ordered enormous
amounts of paper years in advance from paper mills to ensure adequate supply, thus contributing to
deforestation.
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Mining of metal ores was advanced through the use of water wheels, up to 30 feet in diameter, to
power winches and lift buckets with ore. In some cases, these wheels were powered by men running
inside the wheel, much like hamsters use a wheel in their cage! (Bowlus, 1980, pp. 210-218). Iron
mining and smelting was especially important for manufacturing weapons, and large amounts of
wood were used in smelting this and other metals.
Technological advances and better navigational aids permitted European explorers to reach
previously unknown territories. Several trips by Christopher Columbus to the New World beginning
in 1492 opened the Americas to conquest. Vasco da Gama sailed around the Cape of Good Hope
and on to India in 1498. Ferdinand Magellan led five ships around the southern tip of South
America and across the Pacific beginning in 1519. Although he was killed in the middle of the
voyage, Magellans associates completed the round-the-world trek in 1522 which set the stage for
broad exploration and exploitation of lands around the world. The next century saw large numbers
of expeditions from Europe to the New World, Africa and Asia, and even the Arctic.
There were significant environmental implications of these trips. The Europeans brought domestic
goats, pigs, and other animals with them, releasing them in newfound lands. The animals became
feral and in some cases disrupted existing ecosystems. Wherever the ships went, they inadvertently
brought rats which escaped onto the land. Furthermore, natural vegetation in tropical and temperate
climates was often removed and replaced with monocultures of greater value in the home country,
such as coffee and tea. Certain plants in foreign lands were brought back to Europe to provide new
fruits and vegetables. The explorers thus disrupted ecosystems both abroad and at home (Hughes,
2001, pp. 109-110).
Case Study Box: The Conquest of the Inca Empire
Among the worldwide conquests of indigenous people by Renaissance Europeans, the demise
of the Inca Empire by the Spanish explorer Francisco Pizarro in 1533 perhaps best illustrates
contrasting attitudes toward the natural environment. The Incas ruled an empire which
extended 4000 kilometers from north to south, its capital at Cuzco in modern-day Peru. First
established in 1438, the empire had strict laws enforcing conservation of nature for the benefit
of society. The land was managed carefully to avoid deforestation, and irrigation was used to
extend farmland out into the deserts. An elaborate system of roads was built to enable food and
material goods produced in the mountains, rainforests, and coastal areas to be available to
residents throughout the empire (Hughes, 2001, pp. 99-104).
Pollen records show that mountainous regions had been deforested prior to the fifteenth
century, but new forests emerged under the leadership of the Incas. Trees were planted to
surround temples, to provide shade along roads and canals, to beautify towns, and to prevent
soil erosion. Managed forests were used to obtain wood for buildings and for fuel. Wild forests
were protected by the government; wildlife in the forests, especially large mammals such as
guanaco, vicua, and deer, was protected except during annual ceremonial hunts. Other wild
animals were also protected. For example, the Incas needed fertilizer for their farming, and they
recognized the value of guano from seabirds for this purpose. The birds nested on coastal
islands, and laws forbade anyone from setting foot on the islands during the nesting season to
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avoid disturbing the birds. All of these protective rules were strictly enforced with penalties for
violation.
But although the Incas had built a civilization that recognized human dependence on nature,
they nevertheless suffered from political problems. Pizarro arrived in South America during a
war between rivals for the Inca leadership. The Empire was weak and the Inca army was no
match for the more advanced European weapons. Furthermore, the Spaniards brought diseases
previously unknown to South America. The Incas thus came to a swift end under the Spanish
conquest, and with it came ecological disaster: forests were cut down, soil erosion set in, and
irrigation systems failed. The amount of land used for farming fell by more than half. The Inca
civilization, which for a short while had lived in relative harmony with the natural world, thus
became colonized by Europeans who did not share their belief in the importance of conserving
natural resources. Hughes (2001, p. 104) speculates that if the Inca civilization had been
allowed to continue, their population most likely would have grown to the point where the
environment could no longer have supported them. If they realized the dangers this posed,
however, one can speculate that they might have been able to curtail growth and survive as a
sustainable civilization.
(End of box.)
As the Renaissance transitioned into the Age of Reason in the late sixteenth century, new efforts
were underway in the sciences. These efforts led to the Scientific Revolution of the seventeenth
century, known for path-breaking discoveries by such individuals as astronomer Galileo Galilei
(1564-1642), mathematician Johannes Kepler (1571-1630), philosopher Rene Descartes (15961650), and physicist Isaac Newton (1643-1727), among others. This was also a time for
observations of natural processes influencing the earth to test long-standing hypotheses. For
example, in 1674 Perrault measured the rainfall of the Paris basin to determine whether the River
Seine was primarily fed by underground caverns; he showed that the amounts of rainfall were
sufficient to explain the total river flow without contributions from underground sources. But these
discoveries did not yet lead toward an understanding of the impacts of human activities on the
natural world. Scientists and philosophers of the time were engaged in accurately describing the
world around them, but they could not explain the origins of the remarkable order in nature that
they observed: an understanding of evolutional biology was still more than a century off. In fact,
many scientists at this time accepted the idea that God had created the order observed in nature
(Bowler, 1992, pp. 86-87, 108).
The Age of Reason was followed by the Age of Enlightenment starting in the late seventeenth and
extending through the eighteenth century. Enlightenment referred to enlightened attitudes toward
humanity, where traditional values were questioned and interactions among people were guided by
rationality and reason. During this period, subjugation and slavery were challenged as being
irrational by individuals who championed freedom and justice for the poor as well as the rich. The
Enlightenment Age began in France and Britain but also greatly influenced the American
Revolution. The U.S. Constitution and Declaration of Independence are a direct outgrowth of this
Age.
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Scientific studies at this time showed that the earths surface was not static from the time of
creation, as previously believed, but rather constantly changing. Fossils provided evidence that seas
once existed where continents are now, and denuded areas of mountains by rivers suggested that
erosion was a continuous process. People in the eighteenth century were thus more accepting of the
surface of the earth as a constantly changing environment influenced by natural processes rather
than believing the planet would remain unchanged far into the future.
As studies of the earth continued, a notable shift in attitude took place. People in the seventeenth
century had generally regarded the wild appearance of nature jagged mountain peaks, scraggly
fields of natural grass, the uneven surface of a forest floor as unattractive. These people were less
comfortable with the irregularities in nature than with the regular geometric shapes found in areas of
human habitation. The feeling of discomfort with the wilderness gradually changed during the
Enlightenment, as the irregularities of a natural landscape came to be regarded as sources of beauty.
People in the eighteenth century thus developed a greater appreciation for nature.
The science developed during the Renaissance, Age of Reason and Enlightenment was also the
prelude to the development of technology that changed the world in the Industrial Revolution, as we
consider next.
2.8 The Industrial Revolution and Industrial Age, 1750-1950
The Industrial Revolution had its origins in England. Use of wood for smelting had deforested large
areas of England, and in fact most of the cost of smelting iron was due to the high price of wood.
The discovery that coal could be ignited and then starved of oxygen to drive off volatiles and form
coke, a fuel to replace wood, was pivotal in allowing great increases in metal production. In
addition, James Watts steam engine patented in 1769 enabled the energy in a fuel to be converted
to steam capable of producing mechanical work (Sass, 1998, p. 164 and p. 171). Taken together,
these discoveries enabled the rise of mechanization which ushered in a new age of productivity.
The first industries to take advantage of large scale mechanization were producers of cotton
clothing. Factories greatly increased the efficiency of weaving and brought down the cost of
clothing compared to home-based hand weaving operations. Wool spinning became mechanized
shortly after cotton. Other industries taking advantage of mechanization included breweries,
ceramic pottery manufacturers, printing presses, mining companies, and iron and steel
manufacturers. Mechanization also enabled the growth of more efficient agribusiness, increasing the
productivity of the land; an unfortunate consequence was that small farmers were driven out of
business. This resulted in migration of rural families into the cities seeking factory work. In 1831,
31% of the population of Britain was engaged in agriculture, fishing, and forestry; by 1901, only
9% of the population was engaged in these industries (Hughes, 2001, p. 110 and p. 123; Stearns,
2007, pp. 28-32).
The demand for resources grew rapidly. Coal was needed as a fuel for driving most forms of
mechanization, as well as transportation for shipping the outputs of production to consumers. Iron
was needed for the machinery of production, as well as for a wide variety of products ranging from
implements of war to railroads and ships to domestic products such as pots and pans. Lead was used
for water distribution pipes in cities, and lead plumbing became widely used in buildings. Cities
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expanded as factories sprang up, increasing the demand for wood to construct residences for
workers and their families. The demand for food increased as the population rose, and that required
more land to be cleared for farms. Huge amounts of fresh water were needed for industry as well as
for domestic use.
The rise of industry and associated demand for resources had important political implications. The
conquest of new lands begun in the Renaissance accelerated as Englands industrial wealth grew,
enabling access to resources in conquered areas. Land under the control of England at different
times included the American Colonies, Canada, India, Australia, New Zealand, British Guinea,
several countries in Africa, and many islands around the world. By the end of the nineteenth
century, although the American colonies had achieved independence, the British Empire had grown
to occupy about one-quarter of the earths land area and population (Hughes, 2001, p. 124). Other
European countries also acquired colonies and were able to use the resources from those colonies to
their advantage. Examples include the Spanish acquisition of Mexico and parts of central and South
America, the Portuguese acquisition of Brazil, the French conquest of major areas of Africa and
Southeast Asia, and the Dutch acquisition of South Africa and the East Indies. However,
industrialization was slower in continental Europe and did not become a major factor until after the
mid-nineteenth century (Wyatt, 2009, pp. 39, 79-81, and 119-120). In contrast, industrialization in
the United States was already growing rapidly by the time of the Declaration of Independence in
1776.
The environmental implications of industrialization were severe, both in the colonial areas where
resources were extracted and in the home countries, especially England, where factories were
producing goods. Land in the colonies was often transformed to a use that maximized value for the
home country. Examples during the Industrial Revolution included monoculture agricultural areas
for growing coffee, tea, cocoa, grain crops, and cotton, as well as grazing areas for sheep, cows, and
other livestock, and clearing of forests for surface mining of coal and metal ores (Hughes, 2001, pp.
124-125). Environmental damage from factories was of a different nature, generally large discharge
rates of air and water pollutants which caused human illness and damaged ecosystems
(Brimblecombe, 1987; Tarr, 1996). Few natural ecosystems remained in England in any case, as the
majority of the land had already been taken up for food crops and human habitation.
Although we are most concerned with the natural environment, the workplace environment became
important at this time. Many of the workers extracting resources in the colonies were subjected to
unconscionably long hours and poor pay, and in some cases forced labor. The factory environments
were usually no better, with women and children as well as men engaged in highly polluted and
dangerous working conditions.
The influence of the Industrial Revolution was felt globally as resources extracted from colonies
were shipped to factories in Europe and the U.S., and the finished products were shipped around the
world for people who could afford them. Although the quantities of resources needed were huge,
the rate of change was perhaps even more significant. Mechanization allowed the output of work
per unit time for an individual to rise dramatically. There was now more clothing produced per day,
more metal produced per day, and more food grown per season on each hectare of land. As
production per unit time increased, so did environmental damage per unit time. Mechanized
equipment enabled rapid clearing of forest land, and mechanized mining quickened the pace at
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which surface ecosystems were sacrificed to get access to coal and metal ores underneath. People
adapted to more travel as railroad systems grew, increasing consumption of coal as well as the
discharge of pollutants. The population increased at an ever-faster rate: London passed the one
million mark in 1801, reached 2.3 million in 1854 and 6.6 million in 1901. Similar increases
occurred elsewhere around the world.
Improvements in production of metals were especially significant. In 1855, the discovery of an
inexpensive way to remove impurities from iron known as the Bessemer Process revolutionized
mass production of steel. Cheaper and better steel enabled construction of the worlds first
skyscrapers, permitted the design of huge ocean-going ships, enabled greatly improved bridge
design, and gave rise to the automobile with its internal combustion engine. When an inexpensive
way to extract aluminum from bauxite ore was discovered in 1886, world production of aluminum
increased dramatically and was just in time to assist development of the aircraft industry in the
first few decades of the twentieth century. Unfortunately, the environmental damage associated with
production of steel, aluminum, and other metals also increased dramatically.
Although most of the forestland in Europe had long been removed, America offered vast new
forests with tremendous value. Deforestation occurred over huge areas in eastern U.S. during the
nineteenth century, but by 1900 the pace of forest removal reached tens of thousands of square
kilometers per year. As forests disappeared in the eastern part of the country, more lumber
companies moved out west, especially to the Pacific Northwest, where huge trees were available.
Deforestation also became significant in Central and South America as well as in Asia where
millions of hectares of land were cleared.
Much of the deforested land around the world at this time was converted to agriculture to feed a
rapidly growing population. In the U.S., the prairies of the Midwest had been previously covered
with wild grasses that had survived in wet years as well as in droughts. But when these grasses were
replaced with food crops, the natural resiliency was gone. A period of drought in the 1930s made it
impossible to grow crops so that huge land areas became bare. This allowed the soil to be eroded by
winds. The resulting dust bowl was an ecological disaster as well as an economic disaster, as
millions of tons of topsoil were carried away. Hughes (2001, p. 145) notes that such problems have
occurred throughout history when cultivated land was impacted by drought, but the extent of the
problem increased as cultivated land increased.
While deforestation destroys continental ecosystems, overfishing and industrial effluents in the
oceans can severely impact marine ecosystems. The twentieth century experienced such problems
around the world as fishing fleets increased their catch, whaling increased dramaticall y, and
chemicals as well as raw sewage poisoned coastal areas.
Substantial environmental damage also occurred during the world wars in the first half of the
twentieth century. Throughout history, no matter which side wins a war, the environment always
loses. This was certainly true in World War I and World War II as implements of battle became
ever more powerful. The hydrogen bombs developed near the end of World War II demonstrated
that humanity had the capability to result in total destruction of wide areas of the earths surface.
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By the mid-twentieth century, human impact on the planet was significant. But attitudes were about
to change, as we note in the next section.
2.9 The Modern and Post-Industrial Ages, 1950-Present
The launch of Sputnik 1 in October 1957 by the Soviet Union started the space race, an all-out
competition for technical superiority between the East and West. The U.S. responded by launching
the first American satellite into orbit in January 1958. Huge amounts of funding were poured into
research on defense and outer space, and education programs were established to train large
numbers of engineers.
These events were significant from an environmental viewpoint for two reasons. First, an increase
in engineering and scientific research provided new information about the state of the planet as well
as methods to reduce the damage. But perhaps more important, spacecraft photographed the earth
from afar, enabling people everywhere to see the planet as small, vulnerable, and isolated in space.
The need to protect the Earth was immediately apparent to many individuals.
It is no coincidence that environmental activism, a relatively minor influence in the past, reached
new heights in the 1960s. The Clean Air Act and the Clean Water Act in the U.S. ushered in a new
era of environmental regulation, where the number of environmental laws grew and has continued
to grow each year. But at the same time that people were awakening to the environmental damage
occurring around the world, the rising global population was demanding a better lifestyle.
Environmental problems in the last half of the twentieth century and the early 21st century have
reached global proportions. The global circulation of pesticides such as DDT and metals including
lead were mentioned in Chapter A. The ozone hole over Antarctica was discovered in the 1980s,
and the damage was attributed to chlorofluorocarbons used in populated areas. Radiation from the
Chernobyl Nuclear Power Plant explosion was measured around the world. And more recently,
evidence of changing climate due to emissions of CO2 from combustion of fuels worldwide has
been observed. Clearly the activities of billions of people on the planet are having an effect.
2.10 Environmental History as a Guide for the Future
How can we use knowledge of the past to help us move toward a more sustainable trajectory? Of
primary importance is to acknowledge that abuse and overuse of natural resources has been the
norm throughout human development. Deforestation, soil erosion, ecosystem destruction, and poor
waste management are repeated themes. We have seen that when these problems are superimposed
on natural changes in climate, such as the occurrence of a prolonged drought, civilizations can fail.
There are some specific points we can note from the study of environmental history. First and
foremost is the rise of urbanization. From the time of Jericho, it has been clear that farming by a
small number of individuals living on farms can produce enough food for a much larger number,
and that this food can be transported with relative ease. Thus people have the option of living in
cities, where there is some degree of protection and where many options exist for work, play, and
interaction with others. Yet there are also serious problems with cities. The Roman emperors were
aware that huge amounts of food and water had to be brought to the city continuously, and huge
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amounts of waste had to be carried away from the city. A break in an aqueduct or a disruption in
grain delivery could have disastrous consequences for some or all of the one million inhabitants.
Furthermore, the population had to be kept entertained to avoid social unrest bread and circuses
were required. The threat of contagious disease was ever present, especially in conditions where the
population density was as high as in ancient Rome. For all these reasons, the population of cities
was more vulnerable than the population of agrarian folk who could grow their own food and obtain
water from streams and wells.
In addition, we observe that the environmental footprint of an urban population enjoying a high
standard of living is much greater than that of rural populations (Tarr, 2011). The wide variety of
foods available from distant locations, the elaborate buildings and monuments, and, in the case of
Rome, the public baths with their earmarked forests are all examples of luxuries that demand far
more resources than a simple agrarian lifestyle requires.
Our foray into the past also shows us that shortages of resources, whether materials, energy, or
water, have been common throughout history. In cases of material and energy shortages,
civilizations have responded with efforts in re-use, recycling, use of substitutes, and other strategies
which are sometimes considered to be modern solutions to modern problems. In fact, these
activities have been practiced for thousands of years.
Some things are not substitutable, such as ecosystems that provide us with vital services. We cannot
simulate photosynthesis, and we cannot create a web of life through which our physical, chemical,
and biological needs are met. For things that are substitutable, we note that there can be high costs
associated with the substitutions, whether those costs are reflected in undesirable changes in
lifestyle or more expensive implements and services. Furthermore, there are complex trade-offs
such as use of energy resources to produce potable water, which may be difficult to evaluate over
the long-term.
The pattern of every great civilization to rise and fall is noteworthy. Hughes (2001, p. 48) states that
ancient cities tended to grow until the capacity of the local ecosystem was exceeded; the city then
expanded its resources through conquest of areas further away. Eventually, the energy and expense
of bringing resources from afar was greater than the resources themselves were providing, at which
point the growth in population could no longer be sustained. History tells us that when a civilization
can no longer grow, it doesnt simply achieve stability at its maximum population; rather it becomes
unstable and the economy degrades.
The fall of previous civilizations often coincided with changes in climate, especially droughts.
Chew (2007, pp. 169-190) points out that the three major dark periods in the past few millennia
2200-1700 BCE, 1200-700 BCE, and 300-900 CE have engulfed progressively larger land areas,
and he notes that many of the ecological crises we face today are global in extent. Indeed,
globalization has changed the world economy so that we are all dependent to varying extent on the
actions of any individual country.
But we have a major advantage over past civilizations, namely the ability to use technology to help
solve our dilemma. There is no longer an option for the majority of the worlds population to adopt
simple agrarian lifestyles; we are becoming increasingly urbanized and that trend will continue. We
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can no longer expand our available resources through conquest. What we can do, as engineers, is
develop technologies to permit far more efficient use of the resources we have. And we can work
closely with decision makers and the public to ensure that the best science is used to develop and
employ these technologies.
We also have a responsibility to communicate the limits of technology and the limits of the natural
world to others. As engineers, we have the ability to account for those limits in our designs and
ensure that the planets life support systems remain healthy. We also have the ability to identify
those resources that can be distributed worldwide to benefit the most people, rather than focusing
attention on the immediate desires of the wealthiest individuals. Indeed, this is our professional
responsibility, and there has never been a more critical time in human history to act on it.
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