Earth s biomes Environmental factors Abiotic factors non-living chemical & physical factors temperature light water nutrients Biotic factors living components animals plants Marine Tropical rainforest benthos coral reef intertidal distribution: equatorial precipitation: very wet temperature: always warm characteristics: many plants & animals, thin soil Savanna Desert distribution: equatorial precipitation: seasonal, dry season/wet season temperature: always warm characteristics: fire-adapted, drought tolerant plants; herbivores; fertile soil distribution: 30 N & S latitude band precipitation: almost temperature: variable daily & seasonally, hot & cold characteristics: sparse vegetation & animals, cacti, succulents, drought tolerant, reptiles, insects, rodents, birds 1
Temperate Grassland Temperate Deciduous Forest distribution: mid-latitudes, mid-continents precipitation: seasonal, dry season/wet season temperature: cold winters/hot summers characteristics: prairie grasses, fire-adapted, drought tolerant plants; many herbivores; deep, fertile soil distribution: mid-latitude, northern hemisphere precipitation: adequate, summer rains, winter snow temperature: moderate warm summer/cool winter characteristics: many mammals, insects, birds, etc.; deciduous trees; fertile soils Coniferous Forest (Taiga) Chaparral distribution: high-latitude, northern hemisphere precipitation: adequate to dry temperature: cool year round characteristics: conifers; diverse mammals, birds, insects, etc. distribution: coastal mid-latitude precipitation: seasonal, dry summer/rainy winter temperature: hot summer/cool winter characteristics: scrubby vegetation, drought-adapted, fireadapted, herbivores, amphibians, birds, insects Arctic Tundra Alpine Tundra distribution: arctic, high-latitude, northern hemisphere precipitation: dry temperature: cold year round characteristics: permafrost, lichens & mosses, migrating animals & resident herbivores distribution: high elevation at all latitudes precipitation: dry temperature: cold year round characteristics: permafrost, lichens, mosses, grasses; migrating animals & resident herbivores 2
What have we done! Impact of ecology as a science Ecology provides a scientific context for evaluating environmental issues Rachel Carson, in 1962, in her book, Silent Spring, warned that use of pesticides such as DDT was causing population declines in many non-target organisms Barry Commoner s Laws of Ecology Everything is connected to everything else Everything must go somewhere there is no such place as away Nature knows best There is no such thing as a free lunch Laws of Unintended Consequences Acid Precipitation power plants industry transportation nitrogen oxides sulfur dioxide BioMagnification Energy pyramid toxins concentrate as they move up the food chain Acid rain 3
BioMagnification PCBs General Electric manufacturing plant on Hudson River PCBs in sediment striped bass nesting areas Carbon Dioxide Global Warming CO 2 NO x methane Ozone Depletion ozone protects from UV rays CFCs = coolants Bad ozone vs. good ozone Ozone Depletion ozone in smog 4
Deforestation Loss of habitat Loss of biodiversity Loss of stability Loss of Diversity 3 levels of biodiversity genetic diversity inbreeding with shrinking populations community diversity mix of species ecosystem diversity different habitats across landscape All decreased by human activity Driven to extinction purple loosestrife Introduced species Non-native species transplanted populations grow exponentially in new area non-native species out-compete native species lack of competitors & predators reduce diversity gypsy moth Zebra mussel kudzu Overexploitation North Atlantic bluefin tuna Fragmented habitat Loss of food resource for higher levels on food chain Loss of biodiversity Loss of keystone species? Loss of stability Loss of habitat Loss of food resource for higher levels on food chain Loss of biodiversity Loss of stability 5
Biodiversity hot spots Think Globally, Act Locally Restoration projects Any Questions?? 6