Ecology Review

Low BiodiversityHigh Biodiversity 6a. Students know biodiversity is the sum total of different kinds of organisms and is affected by alterations of habitats.

Species diversity greater diversity = greater stability Greater biodiversity offers: –more food resources –more habitats –more resilience in environmental change

Low BiodiversityHigh Biodiversity More stable Less stable

Succession - a series of changes in a community in which new populations of organisms gradually replace existing ones

Secondary succession – takes place on existing soil Primary succession – takes place on bare rock Rock Soil

Succession of species lichens & mossesgrasses treesbushes & small trees pioneer species climax forest compete well in high sunlight more shade tolerant species shade tolerant species stable community

6b. Students know how to analyze changes in an ecosystem resulting from changes in climate, human activity, introduction of nonnative species, or changes in population size.

Acid Rain  nitrogen oxides  sulfur dioxide power plants industry transportation

Carbon Dioxide Global Warming

Ozone Depletion Loss of ozone above Antarctica

Deforestation Loss of habitat Loss of biodiversity

Loss of Diversity Driven to extinction

Overexploitation North Atlantic blue fin tuna

Introduced species Non-native species –transplanted populations grow exponentially in new area –out-compete native species loss of natural controls lack of predators, parasites, competitors –reduce diversity kudzu

Zebra mussel ecological & economic damage ~2 months  reduces diversity  loss of food & nesting sites for animals  economic damage  reduces diversity  loss of food & nesting sites for animals  economic damage

6c. Students know how fluctuations in population size in an ecosystem are determined by the relative rates of birth, immigration, emigration, and death.

6d. Students know how water, carbon, and nitrogen cycle between abiotic resources and organic matter in the ecosystem and how oxygen cycles through photosynthesis and respiration. soil producers consumers decomposers potassium nitrogen iron calcium phosphorus magnesium carbon nutrients can only cycle

Lakes Runoff Percolation in soil Evaporation Transpiration Precipitation Oceans Solar energy Aquifer Groundwater Water cycle Water vapor

Carbon cycle CO 2 in atmosphere Diffusion Respiration Photosynthesis Plants and algae Plants Animals Industry and home Combustion of fuels Animals Carbonates in sediment Bicarbonates Deposition of dead material Deposition of dead material Fossil fuels (oil, gas, coal) Dissolved CO 2

Birds Herbivores Plants amino acids Carnivores Atmospheric nitrogen loss to deep sediments Fish Plankton with nitrogen-fixing bacteria Nitrogen- fixing bacteria (plant roots) Nitrogen-fixing bacteria (soil) Denitrifying bacteria Death, excretion, feces Nitrifying bacteria soil nitrates excretion Decomposing bacteria Ammonifying bacteria Nitrogen cycle

Oxygen cycle photosynthesis cellular respiration

loss of energy sun secondary consumers (carnivores) primary consumers (herbivores) loss of energy producers (plants) decomposers Nutrients cycleEnergy flows soil 6e. Students know a vital part of an ecosystem is the stability of its producers and decomposers.

6f. Students know at each link in a food web some energy is stored in newly made structures but much energy is dissipated into the environment as heat. This dissipation may be represented in an energy pyramid. sun secondary consumers (carnivores) primary consumers (herbivores) producers (plants) loss of energy

Energy pyramid Loss of energy between levels of food chain –can feed fewer animals in each level 1,000,000 10, sun 1000 Loss of energy and heat