Guanting Reservoir (GR) is one of the most important water sources for Beijing and neighboring regions. Due to water pollution, it was withdrawn from the system to supply Beijing drinking water; however, after a thorough treatment process, GR was made a reserve water source since 2007. To develop a comprehensive and quantitative analysis of water yield and purification services in the GR watershed, this study selected two time periods: the period when GR was withdrawn from the system supplying local drinking water and the period that it has been designated a reserve water source. The InVEST model was used to evaluate the quantities of water yields, and total nitrogen and total phosphorus outputs from 1995 to 2010 Additionally, the spatiotemporal variations of water yield services and water quality purification services in the GR watershed were analyzed. The results showed that water yield services in the GR watershed first weakened and then became stronger, but weakened overall during the years 1995 to 2010. Water yield capacity in the basin decreased from 1.89×109 m3 in 1995 to 1.43×109 m3 in 2010 (a drop of 24.0% in total). Water quality purification services also showed the same tendency. Total nitrogen output decreased from 4028.7 t in 1995 to 3611.4 t in 2010, while total phosphorus decreased from 379.7 t in 1995 to 354.0 t in 2010. Nitrogen and phosphorus purification services were enhanced by 10.4% and 6.8%, respectively. Changes in the climate and land use were the main factors which lead to the changes in the water yield service in the GR watershed. Policies intended to protect water resource have matched the varying trends of water quality purification services during different periods. On one hand, the research results provide a foundation to identify key fields for eco-compensation in the Guanting Reservoir basin. On another hand, the ecosystem service value will increase on the basis of eco-compensation criteria through setting the scenarios of returning farmland to forest and ecological protection. This method directly reflects increases in ecosystem service values that have occurred since measures to protect the ecological environment have been implemented. This method is more persuasive and feasible than using eco-compensation criteria based on regional ecosystem service values determined by land use/ coverage type. It can provide a new way to assess eco-compensation in the Guanting Reservoir basin and other regions.
You have requested a machine translation of selected content from our databases. This functionality is provided solely for your convenience and is in no way intended to replace human translation. Neither BioOne nor the owners and publishers of the content make, and they explicitly disclaim, any express or implied representations or warranties of any kind, including, without limitation, representations and warranties as to the functionality of the translation feature or the accuracy or completeness of the translations.
Translations are not retained in our system. Your use of this feature and the translations is subject to all use restrictions contained in the Terms and Conditions of Use of the BioOne website.
Vol. 9 • No. 4