It’s hard to miss any news regarding the consequences of climate change. They range from anything from loss of coastal wetlands to extreme weather events to loss of polar icecaps. Another environmental threat looms that may inflict as much harm as the effects of global warming. It, too, has man-made origins.
Loss of Biodiversity
A new study from an international research team analyzed the effects of loss of biodiversity through a review of two decades of impact studies. Researchers warn that continued extinction of plant and animal species threatens nature’s ability to provide the resources humans need for survival, such as food and potable water.
With a loss of biodiversity comes a reduction in the genetic makeup of an ecosystem. Its genetics provides it with an ability to adapt and survive stresses from the environment. Without the genetic resources, the survival of ecosystems is threatened, along with the resources they provide humans. Other impacts include nutrient cycling, pollination and pollution control.
The human causes of this loss of biodiversity are many. They include habitat degradation and fragmentation. Over-harvesting can also push species to the brink of extinction. Development and urbanization represent additional threats to species survival.
Because of these threats, one in four mammals are at risk for extinction. Already, humans have caused the extinction of nearly 900 species of wildlife. In terms of plants, over 50 percent of the nation’s wetlands have been lost since the 1780s. Less than three percent of native prairie remains.
Assessment of the Threats
The researchers quantified how these impacts would be manifested in terms of plant growth and subsequent effects. The effects were negligible until extinction rates exceeded 20 percent. At this point, plant growth could possibly decline by as much as 10 percent. At rates higher than 40 percent, the effects were comparable to other major environmental problems, such as acid rain.
Because of its implications, the researchers concluded that loss of biodiversity should be considered as part of policy decisions by government leaders. Once the genetic pool has been depleted, recovery may not be possible. How ecosystems respond to these threats will require additional research.