Lecture 23 CH 60 - Biodiversity and Conservation Biology

Genetic diversity

Amount of genetic variation that occurs within and between populations

Species diversity

The number and abundance of species in a community

Ecosystem diversity

Diversity of structure and function with an ecosystem

Endangered species

In danger of extinction in all or a significant part of their range

Threatened species

likely to become endangered in the foreseeable future

Humans depend on plants, animals, and microorganisms for

Food, meds and industrial products and benefits from ecosystem services

Pharmaceuticals

25% of drugs come from plants

Natural products

Harvested from their environment, timber, maple syrup, rubber

Agriculture

Relies upon wild species for pollination and pest control services

Diversity-stability hypothesis

Species-rich communities are more stable than those with fewer species

Redundancy hypothesis

Most species are redundant, not increasing ecosystem function past a ceartin level

Keystone hypothesis

Ecosystem function plummets as soon as biodiversity declines from its natural levels

Idiosyncratic hypothesis

Ecosystem changes unpredictably as the number of species

Mega diversity countries

-the greatest number of species

-Brazil Indonesia Columbia

Hotspots

Threatened areas rich in endemic species

-are biologically diverse and threatened

Endemic species

Found only in a particular place and nowhere else

Representative habitats

approach conserves some of every habitat, instead of just species-diverse ones.

Last of the wind

Supporters protect the areas with the least human impacts

SLOSS debate

Single Large Or Several Small?

• Single large reserve may be able to preserve a larger population

• Or several smaller ones may contain a broader variety of habitats

and a reduced risk to fire or disease affecting all preserved areas at

once

Principles of landscape ecology

Examines the spatial arrangement of elements in communities and ecosystems

Movement corridor

Thin strips of habitat that may permit the movement of individual between larger habitat patches

Edge effects

A special physical condition that exists at the boundary or edge of an area of habitat

Indicator species

Species whose success reflects the overall health of its home ecosystem

-polar bears and corals

Umbrella species

Protecting them also protects many other species

-northern spotted owl

Flagship species

Single large or instantly recognizable species

Attractive engender public support

-American buffalo/ giant panda/ Florida panther

Keystone species

Species within a community that has a special role

-beaver, figs, palm nuts

Complete restoration

Attempt to put back exactly what was there prior to disturbance

Rehabilitations

Return habitat to something similar but less than full restoration

Ecosystem replacement

Replaces original ecosystem with a different one - a deciduous forest replaced after mining by grassland

Reintroductions and captive breeding

Propagation of animals and plants outside thei natural habitat to produce stock for subsequent release into the wild

Sustainable development

Manages natural system so they fill our needs in a way that allows them to keep filling those needs for future generations

Natural capital

The worlds stock of natural resources such as soil water and living organisms