Environmental Policy Quiz 2

Abiotic conditions

physical and chemical environment

Biotic conditions

Living resources and their interactions

Shelford’s Law of Tolerance

Each organism has a range of tolerance for every physical variable (salinity, temperature, etc.)

Generalists

Have a broad niche and diet

Wide range of tolerance

Specialists

Limited by habitat preferences and narrow diet

Keystone species

Species whose role or niche has a large effect on the types and abundances of other species in an ecosystem

Foundation species

Species that play a major role within a community by creating or
enhancing habitats in ways that benefit other species

Umbrella species

• By protecting the area required to maintain a viable population of the umbrella species, managers expect to be able to conserve viable populations of other target species

Distribution and Abundance

• Clumping: most common. Safety in numbers, social interaction

• Uniform: not as common and due to resource scarcity

• Random: rare and hard to determine

Habitats

• An organism's habitat is defined by basic requirements

  • Food and water

  • Space and shelter

  • Optimum environmental conditions