Unformatted text preview: What is environmental biology? Ecology and the Biosphere: Intro t I t to Environmental Biology Interdisciplinary study of how humanity affects other organisms and the environment. environment. EB integrates biology (ecology), geography, chemistry, geology, physics, geography, chemistry, geology, physics, economics, economics, sociology (demographics and population dynamics), natural resources, resources, management, law, religion, management, law, religion, politics. Seasonal variation as a function of sunlight intensity Characterizing the planet where we live Latitudinal variation in sunlight intensity Global air circulation and precipitation 1 Global wind patterns Distribution of Aquatic Biomes Distribution of Terrestrial Biomes BioBio-geographic Realms Factors limiting the distribution of organisms Organismal ecology Population ecology Community ecology Landscape ecology Ecosystem ecology 2 EB paradigm: paradigm: The ways humans live in today's world is environmentally unsustainable! What is environmental sustainability? environmental sustainability? the ability of the environment to function indefinitely without going into a decline from the stresses imposed by human society on natural systems (i.e., soil, water, air, biological diversity) that maintain life. life. Why human society is not operating in a sustainable way?
Humans use nonrenewable resources (i.e., fossil fuels) as if they were present in unlimited supplies. supplies. Humans use renewable resources (i.e., fresh water) faster than they can be replenished naturally. naturally. Humans pollute the environment with toxins as if the capacity of the environment to absorb them were limitless. limitless. Human numbers continue to grow despite Earth's finite ability to support them. Problems of the environment occur in a spatiospatio-temporal context: context:
Global: Global: destruction of Earth's ozone shield, loss of biodiversity, global warming. Regional: Regional: oil spills in Alaska, Gulf of Mexico, Amazonia. Local: Local: conflict humans-wolves in Yellowstone, decline humansof the New England lobster, fisheries in Galapagos. Goal of EB identify ways to avoid upsetting the balance of the biological systems that support humans. Responsibilities of EB suggest how to deal with these imbalances in the most constructive way possible. Examples of environmental problems human impacts on the environment Fast human population growth 1950s eight cities in the world had populations > 4 million; the largest million; New York (12 million). 2000 Tokyo = 28 million inhabitants; the combined population of the world's ten largest cities = 165 million. 3 Old data and projections: 1987 1996 5 billion individuals. 5.77 billion. 4.8 billion people live in developing countries p g 2000 15 megacities with populations >11 million. million. 2010 28 megacities: 22 in developing megacities: countries (e.g. Brazil, India, Indonesia). Brazil, India, Indonesia).
Human population numbers for the last ten thousand years since the advent of agriculture. It took thousands of years for the human population to reach 1 billion, 130 years to reach 2 billion , 30 years to reach 3 billion, 15 years to reach 4 billion, 12 years to reach 5 billion, and 12 years to reach 6 billion. World population started a rapid growth phase in the early 1800s and has grown sixfold i th l t i f ld in the last 200 years. It years. continues to grow by nearly 88 million per year. year. Consequences of rapid population growth:
6 billion people consume: food, water, energy and consume: water, raw materials produce waste. waste. 800 million people consume < 80 percent of the y food. recommended daily levels of food. 2 billion people live in extreme poverty. poverty. As human numbers and consumption increase worldwide, so does humanity's impact on Earth. World population stabilize end 21st. century (10 to 20 billion inhabitants). 4 Discussion
Computer predictions of different variables if current trends in population growth continue. population growth: - Population ecology (demographics). - Cultural, political, economic, religious. - The North vs. South controversy. Rich and Poor dilemma... Figure 1.5 Computer predictions of different variables... (Owen and Chiras 1995). Health problems derived from pollution Chemicals and pollutants endocrine disrupters (interfere with the endocrine system). Plastics: Plastics: polycarbonate found in water jugs. Chlorine compounds: PCBs and dioxins. compounds: Heavy metals: lead and mercury. metals: Pesticides: Pesticides: DDT, kepone, dieldrin, kepone, dieldrin, chlordane, and endosulfan. endosulfan. Wildlife and humans affected by pollutants.
Danish Study sperm counts in 15,000 men (21 nations, US) dropped: 50 percent between 1940 and 1990 dropped: environmental factors??? Discussion - Outbreaks virus. virus. health problems ebola virus, HIV, flu, hanta -A h Anthrax and beyond db d Biological Bi l i l warfare. f Overfishing Fishes harvested faster than they can replace themselves. Economically important fishes commercial extinction Ne unprofitable to harvest.
Figure 11.24 Distribution of world fisheries (Owen and Chiras 1995). Distribution of world fisheries. Coastal areas and upwelling areas together supply over 99 percent of world fish production. The deep ocean forms 90 percent of the ocean area but accounts only 1 percent of the fish catch, if upwelling areas are excluded. 5 1994: National Marine Fisheries Service of the US Commerce Department closed Georges Bank (6,600 square mile area, North Atlantic Ocean), once one of the world's richest fishing grounds. Catches of cod, haddock, and yellowtail flounder steadily declined there during a decade:
Figure 1.5 The harvest of groundfishes... (Raven & Berg 2000). Digital bathymetry map of the Gulf of Maine. Credit: National Oceanographic and Atmospheric Administration and U.S. Geological Survey (USGS) Woods Hole, MA. Other examples: 1960s 1970s: Alaskan salmon fishery declined. 1970s: Peruvian anchovy fishery collapsed. 1990s: Newfoundland cod fishery along the Grand Banks closed ( (North Atlantic). ) 1998: moratorium commercial salmon fishing.
The harvest of ground fish (cod, haddock, and flounder) fot the Georges Bank area declined steadily during three decades. A moratorium on fish was declared in December 1994. Figure 11.28 Pacific sardine catch 1916-1963 (Owen and Chiras 1995). 1916- National Marine Fisheries Service US 80 % of 191 commercially important species have been overfished in US waters acute problem in the Pacific Northwest, Nova Scotia, and the Gulf of Mexico. Worldwide 30 % fish spp. over fished. It is clear that as more effective fishing techniques advance, so does the impact humans have on the environment.
Pacific sardine catch 1916-1963. 1916- 6 Discussion beyond overfishing Declining bird / amphibian populations - Fishing and hunting: surviving in the hunting: rainforest (small scale) the indigenous peoples perspective. perspective. - International trade of wildlife. - CITES, UNEP, WCU. Bird population declines every major group of North American birds. Eastern US 70 % of the 300 to 400 species of migrating birds have declining numbers. Eastern migrating birds winter Central, South America, Caribbean and then migrate north to the US and Canada to breed during the summer. summer. changing environments in both their g g winter and summer homes (loss of habitat reason for their decline).
Stress deforestation, deforestation, fragmenting to accommodate suburban development, agriculture, development, agriculture, and logging. logging. Amphibian decline (and extinction). pathogen induced. pollution (acid rain and endocrine disrupters). d i di t ) habitat fragmentation. global warming induced. UV radiation. Extinction of species
15 percent of Earth's species extinct by 2000s habitat destruction, soil losses, and pollution. Natural extinctions common events in evolutionary history. modern extinctions of plants and animals due to human impact have "catastrophic" proportions.
Figure 4.1 Geologic time showing the principal extinction events... (Raup 1991). (Raup Geologic time scale showing the principal extinction events of the Phanerozoic. The arrow lengths are roughly proportional to the intensity of extinction. The labeled events are the Big Five mass extinctions. 7 Discussion extinctions biodiversity - Cultural diversity (i.e. rain forest). - Types of extinction: genes, individuals, populations, species, behaviors, cultural values associated with biodiversity. - Uses of biodiversity biotechnology. biotechnology. development, economy The Philosophy of Environmental Biology THE TRAGEDY OF THE COMMONS
Hardin, G. 1968. The tragedy of the commons. Science 162: 1243-1248. 1243- Paradigm: Society's inability to solve complex environmental problems result of a struggle between short-term individual shortwelfare and long-term societal welfare. longwelfare. Hardin received a B.S. in zoology from the University of Chicago in 1936 and a PhD in microbiology from Stanford University in 1941. Moving to the University of California, Santa Barbara in 1946, he served there as Professor of Human Ecology from 1963 until his (nominal) retirement in 1978. A major focus of his career, and one to which he returned repeatedly, was the issue of human overpopulation. This led to writings on controversial subjects such as abortion, which earned him criticism from the right, and immigration and sociobiology, which earned him criticism from the left. In his essays he also tackled subjects such as conservation and creationism. In 1994 he was one of 52 signatories on "Mainstream Science on Intelligence", an editorial written by Linda Gottfredson and published in the Wall Street Journal, which defended the findings on race and intelligence in The Bell Curve. Hardin and his wife Jane were both members of the Hemlock Society (now Compassion & Choices), and believed in individuals choosing their own time to die. They committed suicide in their Santa Barbara home in September 2003, shortly after their 62nd wedding anniversary. He was 88 and she was 81 Medieval Europe inhabitants of a village shared pasture land "the commons" each herder could bring animals onto the commons to graze. The more animals a herder brought onto the commons, the greater the advantage to that individual. individual. When every herder in the village brought as many animals onto the commons as possible the plants were killed from overgrazing, and the overgrazing, entire village suffered. suffered. The eventual destruction of the "commons" private ownership of land, because when land, each individual owned a parcel of land, it was in that individual's best interest to protect the land from overgrazing. EB the "commons" "commons" parts of the environment that are available to everyone but for which no single individual has responsibility (i.e., the atmosphere, the ocean, wildlife). 8 ModernModern-day commons GLOBAL COMMONS GC experience increasing environmental stress. Because the GC are owned by no individual jurisdiction, or country, the global commons are susceptible to overuse. overuse. Although the exploitation of the global commons may benefit only a few, everyone on Earth must pay for the environmental cost of overover-exploitation.
The Tragedy of the Commons individual rationality represents -at some point in time and space- collective irrationality! space- Collective irrationality Myers, N. 1995. Environmental unknowns. Science 269: 358-360. unknowns. 358- Hardin (1968) also talks about the "tragedy of freedom" in a "commons" context. context. Examples: Freedom to reproduce, freedom to pollute, freedom to consume. Hardin is difficult to appeal to individual conscience in order to solve public problems i e i.e., overover-population, over-pollution or overoveroverconsumption. " `Freedom' to individual rationality (what may seem the adequate balance between rights and responsibilities) responsibilities) which produces collective irrationality will bring ruin to all." "tragedy of freedom" in a "commons" context Population growth Health problems derived from pollution Over fishing Bird and amphibian decline Extinction of biodiversity Oil spills Introduction of exotic species Ozone depletion Global warming Poverty Why human society is not operating in a sustainable way?
Humans use nonrenewable resources (i.e., fossil fuels) as if they were present in unlimited supplies. supplies. ( , ) Humans use renewable resources (i.e., fresh water) faster than they can be replenished naturally. naturally. Humans pollute the environment with toxins as if the capacity of the environment to absorb them were limitless. limitless. Human numbers continue to grow despite Earth's finite ability to support them. The future? Can our societies grow economically at the same time that we protect the environment?
individual rationality collective irrationality Environmental problems will be solved only with a
multidisciplinary consensus humanistic approach 9 Environmental Groups Politics
The Media Religion Law Economy 10 ...
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- Fall '08
- paz y mino
- Ecology, World population