Ecosystems and Community Chapter 4 Unit 2

Biotic and Abiotic Factors Biotic: the biological influences on organisms within an ecosystem Abiotic: physical or nonliving factors that shape ecosystems

Biotic: Abiotic:

Habitat The area in where an organism lives Includes both abiotic and biotic factors Animals address

The Niche The full range of physical and biological conditions in which an organism lives and the way in which the organism uses those conditions The animals occupation Includes: Type of food the organism eats How it obtains food Which other species use the organism as food Physical conditions organism requires to survive When and how it reproduces

A bear’s niche Type of food it eats: How it obtains food: Who uses the organism as food: Physical conditions required to survive: When and how does it reproduce:

Competitive Exclusionary Principle No two species can share the same niche in the same habitat EX: 3 species of birds live in the same spruce tree but feed at different elevations and in different parts of the trees. Each warbler has a different niche within the forest

Community Interactions Competition: when organisms of the same or different species attempts to use the same source in the same place at the same time EX: plants competing for sunlight Predation: One organisms captures and feeds on another organism

Community Interactions Symbiosis: any relationship in which two species live closely together Mutualism: both species benefits from the relationship Commensalism: one member benefits and the other is neither helped nor harmed Parasitism: one organism lives on or inside another organism and harms it

Ecological Succession Series of predictable changes that occurs in a community over time Primary Succession: Occurs on surfaces where no soil exists Pioneer species: first species to populate the area

Secondary Succession: When a disturbance of some kind changes an existing community without removing the soil Ex: fires, farming

Biomes Terrestrial communities that cover a large area and is characterized by: certain soil climate conditions particular plants and animals Tolerance: ability to survive under different conditions that differ from their optimal conditions

Biomes and Climate Microclimate: climate in a small area that differs from the climate around it

Aquatic ecosystems Determined by depth, flow, temperature, and chemistry of water Grouped according to the abiotic factors that influence them

TUNDRA GRASSLAND DECIDUOUS FOREST CONIFEROUS FOREST

TAIGA DESERT RAIN FOREST DESERT

Freshwater ecosystem Two main types: Flowing-water Standing-water

Aquatic Ecosystems Photic zone: well-lit upper layer Aphotic zone: below photic zone where light cannot penetrate