Human Related Causes of Biodiversity Loss
Exploring the key human-related causes of biodiversity loss: climate change, destruction of habitats and introduction of invasive species.
How far do you agree with the statement that ‘By the end of this century, climate change and its impacts may be the dominant driver of biodiversity loss’?
Biodiversity, or biological diversity, relates to the number and variation of species of organisms on the planet earth. Biodiversity is relevant both in the natural environment and in man-made ecosystems, such as farm land and even urban areas. The primary measure used to measure biodiversity is the number of species in a given ecosystem, and, as such, loss of biodiversity is measured by the extinction rate, which is currently higher than it has ever been, even more so than the five previous mass extinctions in the earth’s history. It is evident that there is some correlation between this and the development of human activity over the last few millennia.
One of the most obvious causes of this loss of biodiversity is climate change. This occurs due to the combustion of fossil fuels which lead to increased levels of greenhouse gases; these prevent energy from escaping the earth’s atmosphere, resulting in temperature rises and unpredictable weather conditions around the world. These environmental impacts can upset the delicate balance present in certain ecosystems, resulting in the extinction of species that cannot adapt or relocate quickly enough to deal with these changes.
However, there are a number of other human-related causes that may have more of an effect than climate change. Overfishing in certain marine environments can result in the extinction of various species of fish and damage to coral reefs, which are a key ecosystem for a number of marine species. Humans can also be instrumental in the introduction of invasive foreign species, such as the American grey squirrel, which has all but wiped out the Eurasian red squirrel in England & Wales. Finally, a major cause of extinctions is due to the physical destruction of habitats caused by urban development. Tropical rainforests are particular havens for a wide diversity of species, and yet many are being cut down to make way for new cropland and pasture for cattle.
While climate change is an ever-present and growing threat it seems likely that, over the next hundred years, at least, all of the impacts mentioned above will continue to be relevant to biodiversity, and will need to be mitigated and reduced if we hope to keep the extinction rate under control.