Biodiversity is the total amount and different amounts of life within a place. Areas with high levels of biodiversity are typically considered healthy ecosystems because the life within the area resists changes to the environment. Populations of living things within healthy ecosystems have lower likelihood of going extinct.
Additionally, healthy ecosystems provide free resources and services which humans can benefit from such as water purification and food. Plus, high levels of biodiversity have aesthetic value to many people. Studying healthy ecosystems and the organisms within them can lead to scientific and technological discoveries, such as new medicines and polymers inspired by chemicals found in living organisms.
One of the largest threats to biodiversity in areas where people live is habitat fragmentation. Habitat fragmentation is the division of large habitats into smaller areas that are no longer connected to each other.
Some organisms need large areas of land to get the food and other resources necessary to support large and healthy populations. Smaller habitats mean smaller and/or weaker populations.
Also as areas become fragmented, populations of organisms can become isolated from each other, which can lead to inbreeding. Inbreeding can cause traits which are not beneficial to the organisms to become more common within a population. Smaller, weaker, and inbred populations are more prone to local extinction. The extinction of one species in an area can cause other extinctions, since populations can depend on each other for survival.
Typically the amount of biodiversity sustained by the fragments is less than a continuous connected habitat of the same size. One way conservationists have tried to support biodiversity in the face of increasing habitat fragmentation is through the use of wildlife corridors. Other names for these features include; green corridors, habitat corridors or wildlife crossings.
Wildlife corridors are small protected strips of land which connect two separated habitats. Sometimes these corridors are land allowed to rewild. Sometimes they are artificial. They can take the form of bridges or tunnels. The types of corridors and the way they work are incredibly varied. Ideally the corridors will allow plants, animals and other organisms to move freely between the two habitats.
The value of these corridors depends greatly on the type of corridors, the organisms being studied, and the goals for the corridors in the habitat. Some organisms do not use the corridors, others thrive in the presence of them. Some corridors have been built too late to have a positive impact. As humans continue to fragment the environment, corridors will continue as a useful tool in lessening the impact on local biodiversity.