Chapter 21
How does the movement of energy and nutrients through an ecosystem differ?
Energy only moves through biotic components while nutrients move through biotic AND abiotic components, sometimes spending longer in "pools".
Identify the 7 major nutrients and give examples of what organisms need them for.
nitrogen- for amino acids, nucleic acids,
phosphorus-
sulphur-
potassium-
calcium-
magnesium-
iron- making hemoglobin,
Describe the processes in the hydrologic cycle.
Evaporation (from bodies of water, soil, and plants), transpiration and precipitation (rain, hail, sleet, or snow)
how can human activities affect the processes in the hydrologic cycle?
Describe the 3 processes that return carbon dioxide to the atmosphere
Respiration- a by-product of organisms that metabolize oxygen
Rock weathering and volcanic eruptions- carbon is stored in rocks, these processes offset carbon burial
Combustion- carbon stored in organic material can be released through fire and the burning of fossil fuels
Explain how human activity has caused an increase in atmospheric CO2 concentration, and why this is a concern.
The burning of fossil fuels releases CO2 into the atmosphere at really high rates, much higher than would ever occur naturally. CO2 is a greenhouse gas so increased CO2 means a warmer planet.
Describe what the bacteria in the root nodules of legumes are doing when they fix nitrogen.
Explain how human activity has altered the nitrogen cycle
Explain what is weathering
Define eutrophication
Explain how eutrophication can lead to ‘dead zones’ in lakes and oceans.
List the main processes whereby detritus is decomposed in terrestrial ecosystems
Which organisms are most responsible for the main processes whereby detritus is decomposed in terrestrial ecosystems
Predict the relative rate of decomposition based on temperature, precipitation, or lignin content
Design an experiment to measure how much the rate of decomposition is affected by the presence of invertebrates.