Transcript Ecology
Chapter 50 Ecology & The Biosphere The Structure of Ecosystems #1 - Biomes Biomes Biomes: a large region characterized by a specific type of climate and certain types of plant and animal communities Biotic Factors Biotic Factors: the biological influences on organisms within an ecosystem Birds, Trees, Mushrooms, Bacteria Abiotic Factors Abiotic Factors: physical, or nonliving, factors that shape ecosystems Climate (temperature, precipitation, humidity, etc.) Wind, Nutrient Availability, Soil Type, Sunlight, etc. Together, biotic and abiotic factors determine the survival and growth of an organism and the productivity of the ecosystem in which the habitat lives. Terrestrial Biomes The Freshwater Province… Pronounced Lake Zones Littoral zone: the area around the edge of the lake that is shallow enough for rooted water plants to grow. Limnetic Zone: the deeper central portion of the lake. Profundal Zone: the zone beneath the limnetic zone that is below the limit of light penetration. The dark profundal zone can only support heterotrophs. Pronounced Lake Zones… Benthic Zone: the zone underlying the entire lake, which comprises the basal layer of sediment. This zone is generally a mucky ooze that is essentially anaerobic. It mainly supports bacteria. The Marine Province About three-quarters of the earth’s surface is covered with water, mostly salty. Neritic province: the part of the ocean in the relatively shallow areas along continents. Oceanic province: the deepwater open sea. The Marine Province … Littoral zone: along the coastline, from the high-tide “spray zone” out to a depth of 200 meters. Euphotic zone: the zone through which light penetrates. Aphotic zone: the zone that is in perpetual darkness. The Oceanic Province Contains the pelagic organisms, those that drift in the open sea. They are mostly restricted to the euphotic zone. The abyssal region is the deeper water region where depths can vary from 300 to nearly 11,000 meters. Abyssal regions support benthic organisms, bottom-dwelling scavengers. Deep Sea Creatures Tropical rainforest distribution: equatorial precipitation: very wet temperature: always warm characteristics: many plants & animals, thin soil 2005-2006 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 2005-2006 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; 2005-2006 deep, fertile soil Chaparral Between desert & Grassland or ocean and forest (think S California: mild winter, hot, dry summer) 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 2005-2006 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. 2005-2006 Arctic Tundra distribution: arctic, high-latitude, northern hemisphere precipitation: dry temperature: cold year round characteristics: permafrost, lichens & mosses, migrating animals & resident herbivores 2005-2006