April 16, 2012
As humans burn more fossil fuels, we emit more greenhouse gases, and bring ourselves closer and closer to the impending doom of global warming. It may seem dramatic and over-played when portrayed in the media, but the consequences are real. Climate can affect global water supplies, increasing our need to conserve water and find more reliable sources especially in desert and temperate environments where water is already scarce. Continuous population growth only aggravates the problem. The problem, however, is not only a matter of water resources for our consumption; water allows for all forms of life on earth. With ever changing water and precipitation patterns in the midst of climate change, fauna and flora globally too will have to reestablish themselves or make other adaptations to be able to survive such a tumultuous time.
Changes in climate will also affect plants worldwide, thereby influencing the distribution of most other forms of life. As plants are at the first trophic level, they convert sunlight into chemical bonds of energy that are made available for next trophic level to use. If climate change stresses water supplies of plants, these effects will easily carry on to all the species that rely on those plants for survival. The natural ecosystems and biomes, or those that remain, will be hard-hit with this accelerating climate change. Plants are adapted to the regions they live in right now, but climate variations can disturb these native plants as well as crops. In this way, climate change has potential to make long lasting and calamitous effects on wildlife all over the world. As humans, we naturally first think of our own food needs, largely coming from agricultural crop and livestock production. Climate change has the potential to cause havoc not just for natural systems but for our industrial farming systems as well. As industrialized as our farming has become, humans still rely on the weather to stay stable and within a temperate range so that their crops can grow. Monoculture planting found in agricultural landscape are especially susceptible to failure under extreme conditions. A few of the possible effects of these climate changes are shown in the graphic below.
Scientific models have attempted to predict how the locations of the earth’s biomes, including agricultural lands, would change. At the rate that carbon dioxide is being released into the atmosphere, plants have little time to be able to evolve to better fit their new habitats. Instead of evolving, the dispersed seeds of flora will now germinate in places where they previously have not been able to because conditions were not compatible with their needs. Plants, biomes, and whole ecosystems will move towards the poles where conditions are more favorable for their growth and they have better access to water, while places closer to the equator will be become hotter and drier. Times like these prove the importance of biodiversity and species richness. The more diverse a certain species, the greater the chance that they will be able to survive a set of extreme conditions that climate change brings. Increased diversity means more alleles, and rare alleles can increase fitness of a species. The benefits of this are only often realized during disturbances. Consider the following graphics that demonstrate such a trend of drifting ecosystems and biomes.
When species find it necessary to migrate, we discover the usefulness and practicality of diverse patches of natural areas even among the most developed urban areas. Connected patches and networks will allow for animals and, more passively, plants to find their way to more suitable environments. This movement also gives species opportunities to mate with other populations thereby increasing their gene diversity and chances to share rare alleles. Biodiversity and allele diversity within species makes those plant or animal populations more stable and resilient following a time of disturbance, like extreme temperatures and precipitation that climate change brings.
Scientists have tried their best with the latest technology to try to incorporate each of the variables and feedback systems to predict specific consequences on various species. For instance, it may be that plants prosper with the excess of carbon dioxide, maximizing plant growth potential and mitigating climate changes. Or, on the other hand, it may turn out that the extirpation of animal species around the world may release 15-20% as much carbon as that coming from anthropogenic causes. Two possible effects are shown below. It is difficult to incorporate the complexities and diverse state of the natural world into a computer model, as well as include slow vegetation responses and species and population interactions. Specific effects of climate change are questionable, but we need to ask ourselves if we are really willing to risk our current systems (agricultural and otherwise) that have been working so well for us.
Of course, this is all assuming that global climate change is inevitable. Scientists are predicting what would happen if we continue to emit at current rates. It is not inevitable; we can help change the projections. We all need to realize the gravity of our choices and actions, especially in regards to energy sources. In the process of preparing for such a series of events, we need to allow for a diverse amount of species to flourish so that disastrous events will not lead to extirpation, or even extinction, of a species. Although indicator species and species that have a narrow range of tolerance will be the first hit, some plants and animals will be able to migrate as a means of adapting to the new set of environmental conditions. Before such dramatic possibilities are considered though, we should first reevaluate our lifestyles and reflect on the long term impacts of our actions on people and life in general all over the world. This way we might be more willing to make necessary adjustments to our lives in order to ensure food and water availability and presence of natural spaces for future generations to enjoy.
This post was authored by Marisa Spinella ’12, who is majoring in Environmental Studies (BS) with a minor in Architecture.
Adams, Richard M., Brian H. Hurd, Stephanie Lenhart, and Neil Leary. “Effects of Global Climate Change on Agriculture: An Interpretive Review.” Climate Research 11 (1998): 19-30. Inter-Research Science Center. 17 Dec. 1998. Web. 9 Apr. 2012. <http://www.int-res.com/articles/cr/11/c011p019.pdf>.
Forman, R.T.T. Land Mosaics: The Ecology of Landscapes and Regions. New York:
Cambridge University Press, 1995