中文摘要：

针对三江源区高寒草地生态系统碳汇管理,本文通过分析三江源区草地生态系统碳流失原因,认为过度放牧是引起系统碳流失的主要因素,而气候变化和土壤养分对系统碳汇没有显著影响;适度利用和维系较高的物种多样性有利于未退化草地固碳功能的维持.依据这些分析,进一步明确了天然草地“取半留半”、轻/中度退化草地“保原增多”和黑土滩退化草地“分类治理”的草地碳汇管理原理.实施退化草地恢复和退耕还草等措施可再次固封以前释放到大气中的碳,转变单一依靠天然草地的传统生产方式为“暖牧冷饲”草地畜牧业生产方式,可提高饲草料利用效率、降低单位畜产品碳排放和实现系统减排.

英文摘要：

In view of management the carbon sink of grassland ecosystem on Sanjiangyuan regions,Qinghai-Tibetan Plateau,this study analyzes the causes of carbon loss in the areas.Overgrazing is the main cause of grassland carbon losses,while climate change and soil nutrition have no significant effects.Moderate grazing and higher species diversity will benefit grassland carbon sequestration.Based on these analyses,we ensure principles of managing grassland carbon sink：＂ Take Half Leave Half＂ for natural grasslands,＂ Maintain Original Add Diversity＂ for lightly and moderate degraded grasslands,and ＂Categorical Management＂ for ＂Black Soil Beech＂ degraded grasslands.Government initiated eco-engineers,such as restoring degraded grasslands and grain for green,could improve ecosystem carbon sequestration,previously it emitted into the atmosphere.It will improve forage utilization efficiency and reduce carbon emissions per unit animal products by changing the traditional livestock production which only relies on natural grasslands to the ＂ Warm Season Grazing and Cold Season Feedlot＂,a new approach of grassland livestock production system to reduce carbon emission.In order to maintain and enhance the carbon sink function of alpine grasslands on the Sanjiangyuan regions,it is an urgent need to use natural grasslands rationally,restoring degraded grassland with high species diversity,constructing fodder production bases with high-quality and extending the new livestock production system.