ecosystem, pop growth

ecosystem, pop growth - Matter in an ecosystem All...

Info iconThis preview shows pages 1–4. Sign up to view the full content.

View Full Document Right Arrow Icon
Matter in an ecosystem - All organisms are made of 6 primary atoms: C H O N P S - Plus: Na Cl K Ca Mg Fe (smaller amounts) - Limited amount of C H O N P S - Matter cycles through biotic and abiotic parts of an ecosystem - We have to get these elements in the right place at the right time - Proper cycling required for life - Disruption of cycling decreases capacity of the earth to support life - No new matter in the ecosystem Cycling of CHONPS - We'll ignore small and trace elements - Concentrate on CHONPS plus H 2 O - Each has reservoir - At any time most of an element is in its reservoir - main reservoir: where most of that element is stored most of the time - Reservoir → Organisms (incorporation) - organisms return to reservoir - incorporation ex: carbon fixation Reservoirs - Can be: - Air: atmosphere - Water: ocean, lakes, streams - Sediment: soil, rocks, seabed - Differ vastly in how accessible they are - Role of decomposers important: - Make CHONPS available from dead organisms, leaf litter and other waste etc. - Recycling: keep it in chemical form that we can use Two major types of reservoir - Reservoir is water or atmosphere - Carbon: CO 2 of atmosphere - Nitrogen: N 2 of atmosphere (80%) - Hydrogen: H 2 O - Oxygen: H 2 O (primary), CO 2 - cycle rapidly - Reservoir is sediment - Phosphorous: PO 4 -3 seabed, soil, rocks - Sulfur: sediment (primary), air - cycling is slow The water cycle - It is essential that water circulates from the earth's surface to the atmosphere
Background image of page 1

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
- Relies on evaporation and precipitation - Evaporation: - Occurs directly from bodies of water - simple, back and forth - Terrestrial ecosystems rely on plants for evaporation (transpiration) - dependence on plants - moves water from soil to atmosphere - Evaporation brings about precipitation - Rains in rainforest because of the trees - Figure 57.2 - Percolation through soil: soil acts as filter - transpiration and evaporation → condensation → precipitation Disruption of the water cycle - Deforestation (large scale clear cutting) - Permanent change in rainfall patterns - Development - Increased water runoff and fresh water loss - Pollution (NYC: freshest water because they got it from the mountains, as development increased in the mountains, NY's water quality went down) - Prevents evaporative cooling: urban heat island - Disruption affects other cycles - Loss of organic nutrients - Alters retention of bio-available forms
Background image of page 2
- 140% of water flow - taking water away from terrestrial ecosystems at increased rate - Ca 2+ , K + , NO 3 - - taking out of the ecosystem, into the water - SO 4 -2 - retained more in the ecosystem Carbon cycle - Carbon is cycled through the biosphere by the twin processes of photosynthesis and respiration - Photosynthesis: CO 2 + H 2 O → Organic sugars (synthesis) - Respiration: Organic sugars → CO 2 + H 2 O (degradation) - Carbon cycling inputs and outputs can be and are unbalanced - Figure 57.1 - Photosynthesis gets CO2 out of the atmosphere, respiration puts it back into the atmosphere - Photosynthesis plants
Background image of page 3

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Image of page 4
This is the end of the preview. Sign up to access the rest of the document.

This note was uploaded on 03/25/2010 for the course BIO 11000 taught by Professor Friedman during the Spring '10 term at Purdue.

Page1 / 10

ecosystem, pop growth - Matter in an ecosystem All...

This preview shows document pages 1 - 4. Sign up to view the full document.

View Full Document Right Arrow Icon
Ask a homework question - tutors are online