In order to better understand the impact that watersheds may have on society we must first understand the definition of a watershed, which according to Sandra Postel and Barton Thompson’s article “Watershed protection: Capturing the benefits of nature’s water supply services,” is an “area of land that drains into a common water source.” The article goes on to mention that due to the fact that watersheds connect different freshwater and coastal ecosystems they provide us with many services that are undervalued and under appreciated. To name a few of the many services, they supply and purify fresh water, provide for a habitat that safeguards and preserves biological diversity, assist in flood control, regulate the flow of water, control erosion of sediment and help with the stabilization of the climate.
The article states that before we make decisions regarding the use and management of watershed lands, we must take into account the value of the natural services that it provides us with.Changing the land into urban settlements reduces the ability of the watersheds to perform these services, thereby reducing the benefits that society derives from it. An analysis of the 106 primary watersheds has found that in almost one third of them more than half of the land has been converted into an urban-industrial use. Furthermore, in Europe 13 watershed lost at least 90 percent of their vegetation and China’s Yangtze and Yellow Rivers have lost 85 and 78 percent of their vegetation.
The loss of natural and healthy watersheds has diminished its ability to perform one of its most important tasks, which is the purification of drinking water. The article states that the loss of this ability will contribute to harm to human health, lower water quality and high water costs as new methods of purification are pursued. Watersheds that have a high proportion of vegetative cover are effective at purifying water supplies. The vegetation and soil has the ability to filter out contaminants and trap sediments that would enter rivers, lakes and streams, thereby providing for a cleaner water source. This high reliability of the water source would also provide for lower treatment and maintenance costs of the watershed. If the watersheds aren’t adequately protected they will provide their dependents with “less clean, less reliable water.” Furthermore, the increase of pollution in the water due to the fact that the watersheds were unable to trap sediments and filter out contaminants can degrade the quality of the water of aquatic habitats.
As a result, I believe that it is important that we attempt to solve this issue from the start, in order to avoid the detrimental effects that it may have on society. We fail to recognize the value that theses ecosystem services provide us with and it is imperative that we gain this understanding before it is too late. People neglect to take into account these services due to the fact that they are provided with no charge and fail to recognize the cost that we would have to pay in order to replace these services. Therefore, it is important that we educate ourselves and strive to maintain these watersheds before it is too late.
Source:
Postel, Sandra L., and Barton H. Thompson, Jr. “Watershed Protection: Capturing the Benefits of Nature’s Water Supply Services.” Natural Resources Forum 29 (2005): 98-108. Print.
