Flashcards › Ch. 3: Community Ecology

A group of interacting populations that occupy the same area at the same time. Community Any abiotic factor or biotic factor that restricts the numbers, reproduction, or distribution of organisms. Limiting Factor An organisms ability to survive biotic and abiotic factors. Tolerance The change in an ecosystem that happens when one community replaces another as a result of changing abiotic and biotic factors. There are two types: Primary and Secondary. Ecological Succession The establishment of a community in an area of exposed rock that does not have any topsoil. Primary Succession The stable, mature community that results when there is little change in the composition of species. Climax Community The orderly and predictable change that takes place after a community of organisms has been removed but the soil has remained intact. Secondary Succession Any nonliving factor in an organism's environment, such as soil, water temperature, and light availability. Abiotic Limiting Factors Include living things, such as other plant and animal species. Biotic Limiting Factors The first plants that begin to grow in a disturbed area, like moss and lichens. Pioneer Species The condition of the atmosphere at a specific place and time. Weather The distance of any point of the surface of the Earth north or south from the equator. This value ranges from 0 degrees at the equator to 90 degrees at the poles. Latitude The average weather conditions in an area - including temperature and precipitation. Climate A treeless biome with a layer of permanently frozen soil below the surface called permafrost. Tundra Also called the northern coniferous forest, to Taiga; lack a permafrost layer and have longer, somewhat warmer summers than in the Tundra. Boreal Forest This forest is composed of mostly broad-leaved, deciduous trees (shed leaves in autumn). This area has four seasons. Temperate Forest Mixed shrub communities are found with less annual rainfall than in the temperate forests. Woodlands Characterized by fertile soils that are able to support a thick cover of grasses. Grassland Any area in which the annual rate of evaporation exceeds the rate of precipitation. These areas can be home to a wide variety of plants and animals. Desert Characterized by grasses and scattered trees in climates that receive less precipitation than some other tropical areas. Tropical Savanna Also called tropical dry forests, grow in areas of Africa, Asia, Australia, and South/Central America; resembles the temperate deciduous forest because the trees drop their leave to conserve water in the dry season. Tropical Seasonal Forest Warm temperatures and large amounts of rainfall throughout the year characterize this biome, with the most diverse number of animals and plants compared to any other biome. Tropical Rain Forest Material that is deposited by water, wind, or glaciers. Deposits form as silt, mud, and sand. Sediment This zone is characterized based on the amount of sunlight that penetrates the water - this area is closest to the shore and is shallow with sunlight reaching the bottom. Littoral Zone This zone is well lit and dominated by plankton. Limnetic Zone Free-floating photosynthetic autotrophs that live in freshwater or marine ecosystems. Plankton This is the deepest area of a large lake with minimal light able to penetrate. This zone is much colder and lower in oxygen. Profundal Zone An aquatic ecosystem saturated with water yet able to support aquatic plants; examples are marshes, swamps, and bogs. Wetlands An ecosystem that is formed where freshwater from a river or stream merges with salt water from oceans. This is a place of transition inhabited by a wide variety of species. Estuary A narrow band where the ocean meets land. Organisms in this zone must be adapted to the constant changes that occur with daily tides and waves. Intertidal Zone In the ocean, this zone is the depth of 200 meters and is shallow enough to allow light to penetrate. Photic Zone Below the photic zone, this depth of the ocean does not allow light to penetrate so it is permanently dark and cold. Aphotic Zone The area of the ocean floor whtat consists of sand, silt, and dead organisms. Benthic Zone The deepest region of the ocean. Very cold water exists in this region with organisms that rely on food that drifts down from the other zones of the ocean. Abyssal Zone All living organisms are limited by factors in the environment.