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Introduction to Ecology

Introduction to Ecology

Author: Jessica Libby
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Ecology is the study of the interaction between organisms and organisms with the environment. This studies both biotic and abiotic factors in an area. Biotic factors include other living organisms (predators/prey) and abiotic are nonliving factors (climate, soil). Climate is the long-term weather of an area which typically includes temperature, precipitation, humidity, sunlight, wind.

Terrestrial Biomes

Tropical rain forest - This biome has the greatest about of biodiversity on Earth. Have vertical stratification or canopy levels. Very little light hits the forest floor which typically consist of small shrubs. Many plants are epiphytes which grow on other plants instead of the soil. 

Temperate deciduous forest - Typically have a mixture of deciduous and coniferous plants. Many animals migrate or hibernate during the fall and winter. 

Coniferous forest (boreal forest/taiga) - Coniferous plants; lots of snowfall

Tundra - Area with no trees; very little rain, cold temperatures, permafrost

Deserts - Little rainfall and extremely hot or cold temperatures

Savannas - Primarily a grassland with some trees. Often have a rainy and drought season. Many plants adapted to fire.

Temperate grassland - Many plants adapted to fire. Nutrient rich soils. 


Source: Holtzclaw, Fred, and Theresa Holtzclaw. AP Test Prep Series. San Francisco: Pearson Education Inc., 2013. Print. ,

Aquatic Biomes

Exhibit vertical stratification. The photic zone is the area where there is enough light for photosynthesis, the aphotic receives very little light and the benthic zone is at the bottom of the biome. 

Freshwater biomes consist of standing water (lakes and wetlands) and moving water (rivers and streams). Estuaries are places where rivers and freshwater sources meet. Lakes are broken into the littoral and limnetic zone. The littoral zone is shallow and closer to the shore. It is well lit and often has plants. The limnetic zone is well lit areas away from shore where phytoplankton is found. The two major types of lake include eutrophic, which are shallow lakes with low oxygen but high nutrients, and oligotrophic, which are deep lakes with lots of oxygen but little nutrients or phytoplankton. 

There are many types of marine biomes including coral reefs, the intertidal zone, neritic zone and pelagic zone. The intertidal zone is the area where land and water meet. This area experiences daily tides so organism alternate between being exposed and submerged. The neritic zone is found over the continental shelves and the pelagic zone is found beyond that. 

Source: Holtzclaw, Fred, and Theresa Holtzclaw. AP Test Prep Series. San Francisco: Pearson Education Inc., 2013. Print. ,