基于AnnAGNPS模型的三峡库区秭归县生态服务价值

Ecosystem service value changes of Zigui county in Three Gorges Reservoir area based on AnnAGNPS model

利用三峡库区秭归县统计和调查资料,并基于AnnAGNPS模型获取秭归县1985、1990、2000、2007年径流、土壤侵蚀和养分流失等数据,客观计量秭归县年际生态服务物质量,进而估算各年际生态服务价值量.结果表明,1985～2007年,秭归县生态服务物质量均发生了变化.2000年径流、泥沙、总氮、总磷和有机碳的年输出量最高,分别为473mm、68.6t/km2、133kg/km2、33kg/km2和684kg/km2,而2007年上述指标最低,分别为419mm、40.6t/km2、112kg/km2、20kg/km2和445 kg/km2,分别下降了12.8%、68.9%、18.7%、65.4%和53.5%;1985～2007年秭归县生态服务价值也发生了变化,2000年最低,为45.1亿元,2007年最高,为54.2亿元,增加了20.1%.利用调查统计和模型输出的方法进行生态服务价值量的计量较为客观准确,避免了一些计算上的不确定性,但该方法所需数据量庞大,可能会限定其他地区的应用.

The changes in value of ecosystem services of 1985, 1990, 2000, 2007 in Zigui county in Three Gorges Reservoir area was studied using statistical and observed data, and annual runoff, sediment yield, nitrogen and organic carbon exported from Zigui based on AnnAGNPS （Annualized AGricultural Non-Point Source） model. Runoff, sediment yield, total nitrogen, total phosphorus and total organic carbon of 2000 exported from Zigui county were the highest, which were 473mm, 68.6t/km2, 133kg/km2, 33kg/km2 and 684 kg/km2, respectively. All the above quantities of 2007 were the lowest, which were 419mm, 40.6t/km2, 112kg/km2, 20kg/km2 and 445kg/km2, and which reduced by 12.8%, 68.9%, 18.7%, 65.4% and 53.5%, respectively. The value of ecosystem services in Zigui county were also changed in different years. The values of ecosystem services were 45.1× 10^8 Yuan （2000） and 54.2× 10^8 Yuan （2007） respectively, which increased 20.1%. The method using observed data and AnnAGNPS model was objectively which can reduce the uncertainty of the quantity of ecosystem services. This method not only needed a large amount of data, but also had a very complicated process, and which might be influenced by multiple factors above. This might limited the scale and depth in assessing the values of ecosystem services in some other places.