How Climate Change Affects Biodiversity
The impact of climate change on biodiversity is comprehensive, including impacts on inheritable diversity, species diversity and ecosystem diversity.
Climate change will have a profound impact on the uproarious ness, distribution pattern, interspecific connections, phenology, photosynthesis, etc. of factory species, and increase the threat of irruption of alien species and extermination of original species. For illustration, in the last decade of the 20th century, as the temperature rose, the number of thermophilic factory species in the Netherlands increased. Climate warming will beget some shops to extend their growing seasons, bloom before, grow briskly, and disrupt being intermediate connections. The areas where climate change has the topmost impact on factory diversity are those where species have fairly fixed territories and can not resettle. thus, species with small populations and fractured territories, or species with islet- suchlike distributions, are fairly more vulnerable to climate change.
Temperature has a decisive influence on the hatching results of some reptiles and amphibians, and the hatching temperature can determine the coitus of the seed. For illustration, for some ocean turtles, when the incubation temperature is lesser than 29 ℃, utmost of the incubated baby turtles are womanish, and when the incubation temperature is lower than 27 ℃, utmost of the incubated baby turtles are manly. For the Chinese alligator, when the incubation temperature is 28.5 ℃, all the incubated baby alligators are womanish, and when the incubation temperature is 33.5- 35 ℃, all the incubated baby alligators are manly. This means that under the background of continued temperature rise, some turtles and crocodiles may face the trouble of extermination. Some symbiotic, parasitic and food chain species may disrupt the interspecific connections formed by long- term elaboration due to the different perceptivity of each species to temperature.
Climate change will also lead to changes in the structure, function and diversity of ecosystems. For example, changes in the spatiotemporal pattern of precipitation caused the density of woody shrubs in the Chihuahua Desert in the United States to increase threefold in the 1970s , and the number of previously common animals decreased while the number of rare animals increased. In addition, rising temperatures increase plant productivity in high-latitude terrestrial ecosystems and change the carbon and nitrogen cycle process of ecosystems. The natural condition of ecotone is one of the areas most sensitive to climate change. For example, the semi-tundra transition zone in the Changbai Mountains in China has widened, and some plants in the alpine meadow and forest line transition zone in the Wutai Mountains have migrated to higher altitudes. The boreal forest is expanding northward at a speed of 100-150 kilometers per 1 °C increase in temperature. Global warming is causing the ecosystem as a whole to move toward the poles and high altitudes. The abundance of herbaceous and lichen plants in the tundra has changed, thereby changing the structure, composition, function and services of the ecosystem.
It is predicted that future climate change will lead to changes in the structure and function of marine ecosystems. For example, seawater temperature rises, ice cover decreases, salinity and oxygen change, marine biological distribution and phenology change, algae, plankton and fish in high-latitude oceans migrate toward the poles, and the biological richness, community structure and service capacity of marine ecosystems will change. According to the IPCC report, if the global temperature rises by 1 °C, coral reefs around the world will be bleached, and rising sea levels will cause coastal wetlands to be submerged. It is estimated that by 2080 , 20% of wetlands will be lost, and mangrove ecosystems will be greatly affected. Climate change will also have a great impact on marine plankton, especially polar ecosystems. The phenology and distribution of many marine and freshwater organisms will also change with the increase in water temperature, changes in ice cover, oxygen content and circulation changes. Algae, plankton and fish migrate toward the poles in terms of range and abundance.
Climate change will also affect the biodiversity conservation function of nature reserves, and will bring great pressure and challenges to biodiversity conservation in future reserves. Climate change causes some species to migrate in search of new suitable habitats, and some species even migrate to habitats outside the reserves, causing these species to disappear within the reserves, which will be detrimental to the effective protection of these species by the reserves. Climate change may also make the boundaries of the reserves no longer suitable, and the original management no longer effective.
Climate change will also increase the frequency of extreme weather events, such as blizzards, floods, droughts, etc., which will damage plants and animals and destroy ecosystems. The increase in the frequency of fires will also cause devastating damage to ecosystems.
