Terrestrial and Aquatic Biomes Flashcards

-Typically receive 200+cm rainfall annually
-Vertical layered, competition for light is intense
-Most diverse terrestrial biomes
-Being destroyed at high rates for agriculture

-Typically found where air masses descend
-Receive less than 30 cm annually
-Are dominated by succulents w/ adaptations to heat and desiccation tolerance
-Many species of animals are nocturnal
-Long distance transport of water and deep groundwater wells have allowed substantial human settlement (especially in US)

-Tropical grasslands, with warm temperature year round-Dry season which can last up to eight or nine months-Fires common in dry season, plant species fire-adapted -Grasses and forbs are tolerant of grazing by mammals-Large grazers (and predators) are visible components but dominant herbivores actually insects-Migration of grazers and fire important in maintaining

-Experience cool, rainy winters and hot, dry summers-Are dominated by grasses, herbs, shrubs and small trees,-Plants have adaptations to drought and to fire-Have high diversity of small browsing mammals-Have been heavily settled by humans

-Cold, dry winters and hot, wet summers-Are dominated by grasses and forbs, with adaptations to drought and fire-Grazing by large mammals (and fire) prevent establishment of woody shrubs and trees-Are also inhabited by a wide variety of burrowing mammals-Have been converted to farmland at a high rate

-(Currently) the largest terrestrial biome-Experience cold winters-Are dominated by conifers (gymnosperms), whose shape prevents snow accumulation on branches-Many migratory birds nest in this biome -Are being logged at high rate

-Show seasonal climates-Are vertically stratified dominated by deciduous trees -Many mammals hibernate in winter-Bird species migrate to warmer climates

-Cover 20% of Earth’s surface
-Have a permanently frozen layer of soil, the permafrost
-Covered by mosses, grasses, forbs, and some dwarf shrubs
-Dominated by migratory mammals (moose, reindeer)
-Has been exploited for mineral and oil extraction

-Temperate lakes may have a seasonal thermocline, while tropical lowland lakes have a thermocline year-round-Oligotrophic lakes are nutrient-poor and generally oxygen-rich, while eutrophic lakes are nutrient-rich and often depleted of oxygen-Runoffs from fertilized land and wastes lead to nutrient enrichment and eutrophication

-Are habitats that are inundated by water at least some of the time and support plants adapted to water-saturated soil
-Water and soil are periodically low in dissolved oxygen-Some of the most productive biomes -Draining and filling have destroyed up to 90% of wetlands

-Headwater streams are generally cold, clear, turbulent, swift; they have high oxygen levels-Downstream water are generally warmer and more turbid, and depending on organic enrichment, may have less oxygen-Nutrient enrichment, damming and flood control have impacted these biomes

-Are transitions areas between rivers and sea-Subject to tides and salinity fluctuations-Some of the most productive biomes and nurseries for many marine invertebrates and fishes-Filling, dredging, and pollution have disrupted

-Periodically submerged and exposed to tides-Oxygen and nutrient levels generally high-Organisms show adaptations to exposure-Can be rocky or sandy-bivalves, worms, sponges, echinoderms, etc.

-Higher water clarity extends photic zone to greater depth-Oxygen levels high but nutrient concentrations low-Largest biome (70% of Earth’s surface)-Turnover in temperate zones-Phytoplankton, zooplankton (krills), fishes, whales and dolphins-Overfishing

-Formed largely from calcium carbonate skeletons of corals-Corals require high oxygen levels-Most diverse aquatic biome-Many mutualisms-Large scale coral death probably due to global warming and pollution (with collecting)