ENSC ch 6 - Summary Environment PDF

Preview

Summary

enviro...

Description

Ch. 6  Earth has many climates in regards of the location o Organisms learn to adapt to those climates  Biome: Large regions that have small ecosystems no matter where in the world it is o Nine different biomes:  Tundra  Treeless area with swampy plains, Nutrient poor soils, and have a little organic litter  Covered in lichens and moss  Very harsh, cold winters, and short summers  Permafrost: permanently frozen ground  Low species richness and primary productivity  Human interference: oil, natural gas, etc. pushes be already slow regenerating tundra to take longer  Climate change is causing the permafrost to melt, allowing trees to root, which increases more warmth in the area due to albedo  Boreal forest  Region of coniferous forest, extremely cold and severe winters, Little precipitation, acidic and mineral poor soil with deep layers of partly decomposed pine and Spruce needle  Has patchy permafrost and numerous ponds and lakes created by glaciers  Mostly this deciduous trees  Land not useful when it comes to agriculture, how over good for lumber, pulpwood, animal fur, etc. o World’s primary source of industrial wood and wood fiber  Mining, drilling, and farming has contributed to the loss of the forest  Temperate rainforest  Coniferous bio, cool weather with high precipitation  Nutrient poor soils even with high organic content due to amount of time it takes to decompose  Full of evergreen trees, mosses, lichens, ferns, etc.  Rich supplier of wood/lumber and easily vulnerable due to how long it takes to regenerate  Temperate deciduous forest  Hot summers/cold winters  Has rich soil with organic material and deep clay-rich lower layer  Broad-leaved trees dominate the Forest  Human interference: logging, land clearing for farms, cities  Grassland  Hot summers/cold winters, uncertain rainfalls  Soil contains considerable organic material  Not many trees unless near pond/lakes but a lot of grass  Covered in herds of animals  Ideal area for agriculture

Chaparral  Mild, moist winters, hot, dry summers  Soil is not fertile because it is thin  Frequent fires naturally  Dense growth of evergreen shrubs with drought-resistant pines that grow best after a fire  Fires tend to be stronger since humans try to stop natural fires altogether  Deserts  Dry land, lacks precipitation, limited growth  Soil is low in organic material but high in mineral  Full of cacti, sage bushes, Joshua trees, etc.  When people drive over non-road areas, they disturb the soil and make erosion occur more readily, also people who live in deserts take up all the ground water  Savanna  Tropical grassland with seasonal rainfall  Somewhat nutrient low soil due to leaching  Humans are quickly turning these land into rangeland for cattle  Tropical rainforest  Warm temperature throughout the year with rainfall almost daily o Rainfall makes soil mineral low, also all the fungi and bacteria  Lush greenery and rich species  Humans interfere with these forest through industrial expansion o Can cause rainforest extinction Vertical zonation o Hiking up a mountain is similar to traveling towards the North pole  As you climb a mountain, temperature drops just as If moving north  Types of organisms change as well due to different temperatures o At the bottom of the mountain, there would be the deciduous trees That shed during the fall o Near the middle of the mountain, there would be coniferous trees that are yearround o At the top, there would be with vegetation like, moss, grasses, sedges as well as permanent ice caps Aquatic ecosystems o Salinity: concentration of salt and bodies of water  Can affect what types of organisms living in certain areas o Nutrient minerals can limit amount and distribution of organisms in certain environments o Other things that may affect aquatic life: temperature, pH, waves, and current o Three ecological categories  Floating plankton  Small microscopic organisms that are carried by ocean currents  Found in different depths of water depending on time and season 





Phytoplankton: Photosynthetic algae that are the basis of most Aquatic food web  Zooplankton: non-photosynthetic, tiny shrimplike crustaceans and larvae that feed on algae  Strong swimming nekton: fish, turtles, and whales  Bottom dwelling benthos: organisms that fix themselves on one spot, Burrow into sand or just walk on the seafloor  Oysters, barnacles, clams, sea cucumbers, crawfish, larvae, etc. Fresh water ecosystems o Assist in recycling precipitation o Flowing water ecosystems (Rivers and streams)  Various conditions exist along those waters  Surrounding Forest may give the water shape or complete sun  Headwater streams: Source of the river, usually shallow, cool, swift flows, highly oxygenated  These different conditions create different habitat  Headwater to mouth = River continuum concept  Streams and rivers depend on land for most of the energy  Pollution and physical environmental changes alter these waters  Not only does it hurt organisms, But also our water supply o Standing water ecosystems (Lakes and ponds)  Lakes have three zones  Littoral: shallow water area along the shore, most productive due to the sunlight in nutrient from surrounding land  Limnetic: open water away from the shore, less vegetation due to its depth  Profundal: No light penetrates this area, bacteria decompose whatever flows down, mineral rich and has hardly any oxygen  Thermal stratification and turn over  Sharp changes of temperature due to how the sun penetrates the water  Full turnover: lowering of temperature in autumn mixes the lake water, bringing mineral rich water to the top  Spring turnover: when ice melt and surface water lowers as lower water rises to the top o These turnovers cause bloom due to the mineral rising to the top o Freshwater wetlands (Marshes and Swamps)  Dominated by woody trees or shrubs  The soil is rich in organic material  Plants are highly productive and support many other organisms  Ecosystem service: Where these wetlands cleanse the water by trapping pollutants Estuaries: Where ocean water meets freshwater o Salinity gradually changes within the estuary 











o Most fertile ecosystem due to nutrients transported from land to estuaries, tides circulate nutrients, high levels of light penetrate the water, and plans provide more photosynthesis o Mangroves and salt marshes Marine ecosystems o Intertidal zone: Between low and high tides where organisms live along the shore  Vulnerable due to constant changes of environment o Benthic environment: Ocean floor (Seagrass beds, kelp forests, coral reefs)  Consists of sediments o Pelagic environment: Vast marine system  Heretic province  Water not over lies the continental shelf  Jellyfish, zooplankton’s, Sea urchins  Oceanic Providence (Deep-sea)  Largest marine environment that overlies the ocean floor  Giant squid, dragon fish National Marine sanctuary’s o Area set aside along the coast of the US to minimize human impact and protect unique/historical sites  Ex. Kelp forests, coral reefs, fishing grounds, shipwrecks, etc. o Administered by the national marine sanctuary program Humans interfere the ocean with resorts, cities, industries, and agriculture along the coast o Can destroy coastal ecosystems since it receives the pollution from these developments o Viruses and bacteria from sewage contaminate seafood, only increasing human health o Millions of trash and death in marine ecosystems hurting organisms o Contaminants from agriculture/industry hurts the ecosystem as well...