Habitat Fragmentation and It's Effect on Biodiversity
Habitat Fragmentation is the process by which part of an organism's preferred habitat range becomes inaccessible. It is the single greatest threat to biodiversity throughout the biosphere. Almost always, habitat fragmentation is caused by human activities such as agriculture, urban development, forestry, and mining. Many species become extinct when they lose their habitat, or when they cannot move to an alternative habitat. As the human population continues to expand, and they take over more and more space over the last few hundred years, more and more species have become extinct or categorized as endangered, vulnerable, or rare.
Agriculture and Urbanization
As the human population increases at an exponential rate, we have been destroying and decimating the habitat's of many species in order to make way for cities and towns, and also for farmland. This graph shows a direct correlation to the growth of the human population and the increase in the extinction of many species.
Urbanization and Mining
Humans also carelessly destroy the lands, the places where many species live and thrive, by cutting down the trees and destroying land for mining. In this picture, you can clearly see the devastating effects on mining on the land. It completely destroys the area where many species thrived and biodiversity flourished. There is usually nothing left, and it would take many, many years for the land to heal and for it to become habitable again.
Habitat Fragmentation's Occurrence Over Immense Regions
Habitat fragmentation does not only occur in small areas, but also over immense regions. For example, in 98% of the dry forest in Central America and Mexico have been cut down. In Veracruz, Mexico alone, they have cut down almost 90% of the original forest in order to make space for cattle ranching. In almost all cases, habitat fragmentation has lead to species loss because the smaller populations in habitat fragments have a higher probability of local extinction.
A Major Threat to Aquatic Biodiversity
As a result of human activities, 93% of coral reefs, among Earth's most species-rich aquatic communities, have been damaged. At the current rate of destruction, 40-50% of of the reefs, home to one-third of the marine fish species, could disappear in the next 30-40 years. Some of the human activities done that have greatly damaged the coral reefs include the construction of coastal protection, land reclamation, sand and gravel extraction, recreation and development including ports, harbors, and industries.
The Effects on Freshwater Habitats
Freshwater habitats are also lost because of dams, reservoirs and channel modifications, and flow regulation. In the southeastern part of the United States, more than 30 dams and locks have been built along the Mobile River basin. This changed the river depth and flow, which lead to the extinction of more than 40 species of mussels and snails.