Indicator Species Keystone Species Foundation Species K-strategist R-strategist
A: Represents the biotic potential of the species B: Shows how the population overshoots the carrying capacity C: Represents the logistic growth D: Represents linear growth E: Carrying capacity- the maximum number of individuals that can be supported by a particular ecosystem.
Human Impacts on the Hydrologic Cycle Withdrawal ◦ Water cannot recharge at same rate (Ogallala Aquifer) ◦ Salinization (Aral Sea) Increased Flooding ◦ Urbanization “concrete jungle” Deforestation ◦ More runoff
Cycles Carbon Nitrogen Sulfur Phosphorus Which does not have an atmospheric component to it’s cycle?
Human Impacts on Aquifers Withdrawing too much water – doesn’t allow adequate recharge Building cities over recharge areas
Fig. 14-13a, p. 317 Provides water for year-round irrigation of cropland Flooded land destroys forests or cropland and displaces people Large losses of water through evaporation Provides water for drinking Downstream cropland and estuaries are deprived of nutrient-rich silt Reservoir is useful for recreation and fishing Risk of failure and devastating downstream flooding Can produce cheap electricity (hydropower) Downstream flooding is reduced Migration and spawning of some fish are disrupted
The Colorado River So many diversions, water often does not reach the ocean
Wetlands Swamps, marshes, peat bogs, prairie potholes Filter and degrade pollutants. Filter and degrade pollutants. Reduce flooding and erosion by absorbing slowly releasing overflows. Reduce flooding and erosion by absorbing slowly releasing overflows. Help replenish stream flows during dry periods. Help replenish stream flows during dry periods. Help recharge ground aquifers. Help recharge ground aquifers. Provide economic resources and recreation. Provide economic resources and recreation.
Tragedy of the Commons Over-use of public lands Often seen with fishing, but can apply to grazing, hunting and other public uses of land This is a HUGE concept on the test ◦ Many previous multiple choices ◦ A few FRQs have been on this
Measurements of Biodiversity Species Diversity Species Evenness Species Richness Higher species diversity leads to higher sustainability of an ecosystem