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Earth’s biomes. Environmental factors. Abiotic factors non-living chemical & physical factors temperature light water nutrients Biotic factors living components animals plants. Marine. coral reef. benthos. intertidal. Tropical rainforest. distribution : equatorial
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Environmental factors • Abiotic factors • non-living chemical & physical factors • temperature • light • water • nutrients • Biotic factors • living components • animals • plants
Marine coral reef benthos intertidal
Tropical rainforest distribution: equatorial precipitation: very wet temperature: always warm characteristics: many plants & animals, thin soil
Savanna distribution: equatorial precipitation: seasonal, dry season/wet season temperature: always warm characteristics: fire-adapted, drought tolerant plants; herbivores; fertile soil
Desert 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
Temperate Grassland 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
Temperate Deciduous Forest 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) distribution: high-latitude, northern hemisphere precipitation: adequate to dry (temperate rain forest on coast) temperature: cool year round characteristics: conifers; diverse mammals, birds, insects, etc.
Arctic Tundra distribution: arctic, high-latitude, northern hemisphere precipitation: dry temperature: cold year round characteristics: permafrost, lichens & mosses, migrating animals & resident herbivores
Alpine Tundra distribution: high elevation at all latitudes precipitation: dry temperature: cold year round characteristics: permafrost, lichens, mosses, grasses; migrating animals & resident herbivores
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 ofpesticides such as DDTwas causing populationdeclines in manynon-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
nitrogen oxides • sulfur dioxide Acid Precipitation • power plants • industry • transportation
BioMagnification • PCBs • General Electric manufacturing plant on Hudson River • PCBs in sediment • striped bass nesting areas
CO2 NOx methane
Ozone Depletion protects from UV rays
Ozone Depletion • Loss of ozone above Antarctica
Deforestation • Loss of habitat • Loss of biodiversity
Loss of Diversity • 3 levels of biodiversity • ecosystem diversity • different habitats across landscape • community diversity • mix of species • genetic diversity • inbreeding with shrinking populations • All decreased by human activity
gypsy moth Introduced species • Introduced species • transplanted populations grow exponentially in new area • non-native species out-compete native species • lack of competitors & predators • reduce diversity • examples • African honeybee • gypsy moth • zebra mussel • purple loosestrife kudzu
~2 months Zebra mussel
Purple loosestrife • Non-native species out-compete native species • lack of competitors & predators • reducing diversity • causing loss of food & nesting sites for animals • Video 1968 1978
Overexploitation North Atlantic bluefin tuna
Think Globally, Act Locally Any Questions??