It can reduce habitats to a size that is too small to support some species
By creating islands of habitat in a sea of human-dominated landscapes, fragmentation
reduces the ability of individuals to disperse from one habitat to another.
Fragmentation creates large amounts of “edge” habitat.
Biomass declines sharply along edges of forest fragments. The large trees near forest
edges tend to die due to exposure of high wind and dry conditions.
View from genetics: 1, When populations are fragmented into a metapopulation structure,
gene flow between isolated groups is reduced or eliminated.
2, Genetic drift is much more pronounced in small populations than large
3, Small populations become inbred, and inbreeding often leads to lowered
fitness- inbreeding depression.
**When habitats are fragmented, the quality and quantity of habitat decline drastically. In
addition to losing over 8 million hectares of primary forest in South America an Africa each
year, we are losing large amounts of high quality habitat to fragmentation.***
Estimate Extinction Rate
Direct count on the species that are extinct recently and those that are imminent to
Predict the consequence of habitat loses
Although invasive species remain a major threat to biodiversity, the majority of current
problems are on continents and are due to habitat destruction and fragmentation.
Current and projected extinction rates can be estimated from direct counts and from an
analysis of species-area relationship.
55.4 Preserving Biodiversity
How? Prevent the loss of alleles, species , and ecosystems
Sustain diverse communities in natural landscapes while supporting the extraction of
resources required to maintain the health and well-being of the human population
Sustainability- the managed use of resources at a rate only as fast as the rate at which they are
Q: Do high species richness and high functional diversity of species incr