Ecology Part 2. Living Environment

Transcription

1 Ecology Part 2 Living Environment

2 Recycling in the Biosphere Matter is recycled within and between ecosystems Elements, chemical compounds, and other forms of matter are passed from one organism to another AND they are passed from one part of the biosphere to another through BIOGEOCHEMICAL CYCLES

3 Biogeochemical Cycles Cycles that connect biological, geological, and chemical aspects of the biosphere Biological systems don t use up matter, they transform it Assembled into living tissue or passed out of the body as waste

4 Story Time! You are a carbon atom in a molecule of carbon dioxide floating in the air You are taken in by the leaf of a blueberry bush during photosynthesis and become a part of a carbohydrate molecule that produces a blueberry The blueberry (you) are eaten by a caribou and then excreted out of its body You are then swallowed by a dung beetle which is then eaten by a shrew, and the shrew is eaten by an owl The owl exhales and you are re-released as CO2 into the environment and the cycle begins again

5 The Water Cycle Moves between the ocean, atmosphere, and land Enters the atmosphere as water vapor (gas) when they evaporate from bodies of water Water can also evaporate from the leaves of plants in the process of transpiration

6 The Water Cycle Once the water vapor is evaporated, it will condense into tiny droplets that form clouds When the droplets get big enough, it rains (or snows, or sleets, or hails) Once it hits land it is either carried into streams and rivers, soaks into the soil to become groundwater, or enters plants from their roots Then the cycle repeats itself!

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8 Nutrient Cycles Nutrients all the chemical substances that an organism needs to sustain life The body s chemical building blocks Every organism needs nutrients to build tissues and carry out essential life functions Nutrients are passed between organisms and the environment through biogeochemical cycles

9 The Carbon Cycle There are 4 main processes that move carbon through its cycles: 1. Biological processes 2. Geochemical processes 3. Mixed biogeochemical processes 4. Human activities

10 Biological Processes Photosynthesis Respiration Decomposition All take up and release carbon and oxygen

11 Geochemical Processes Processes that take place in the earth such as erosion and volcanic activity Releases carbon dioxide into the atmosphere and the oceans

12 Mixed Biogeochemical Processes Burial and decomposition of dead organisms Conversion of dead organisms under pressure into coal and petroleum Carbon is stored underground

13 Human Activities Mining Cutting (forests) Burning (forests and fossil fuels) All release carbon dioxide into the atmosphere

14 Carbon Cycle Carbon is in the atmosphere as carbon dioxide (released by volcanoes, respiration, decomposition, and burning of fossil fuels) Plants take in CO2 to build carbohydrates during photosynthesis Carbohydrates are passed from producers to consumers When animals die, they break down and carbon is returned to the cycle

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16 The Nitrogen Cycle Organisms need nitrogen to make amino acids which are then used to build proteins Nitrogen gas makes up about 78% or Earth s atmosphere Ammonia, nitrate ions, and nitrite ions are found in waste Nitrogen is also found in the ocean as well has in fertilizers (human influence)

17 The Nitrogen Cycle The most abundant form of nitrogen is in the atmosphere Some bacteria can use atmospheric nitrogen in a process called nitrogen fixation Bacteria live in the soil and on the roots of plants called legumes, convert N2 gas into ammonia which is then used by the plants

18 Nitrogen Cycle Cont d When organisms die, decomposers break down their bodies and return nitrogen to the soil Soil bacteria then convert that nitrogen in the soil (nitrates) into atmospheric nitrogen in a process called denitrification

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20 The Phosphorus Cycle Phosphorus helps organisms form DNA and RNA It is not common in the atmosphere and mostly found in rocks, soil, and the ocean sediments Phosphate washes into streams and makes its way to the ocean where it is then taken in by marine organisms On land, phosphate cycles between soil and organisms that eat it

21 Primary Productivity The rate at which organic matter is created by producers A factor that controls this is the amount of available nutrients If a nutrient is in short supply is will limit growth of a plant

22 Limiting Nutrients A nutrient that is scarce or cycles slowly thus limiting the growth of plants Fertilizers are used by farmers to stop this phenomenon from occurring Usually contain nitrogen, phosphorus, and potassium

23 Algal Blooms Excess fertilizer enters waterways as runoff It ends up in larger bodies of water where extreme, unlimited algae growth can occur This causes algal blooms Disrupts equilibrium and removes oxygen from the water killing fish and other wildlife

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