近30年淀山湖地区生态系统服务价值对土地利用变化的响应

The responses of ecosystem services to land-use change in Dianshan Lake area from 1984 to 2014

水源是区域和城市发展的重要保障,研究其生态系统服务的变化及其影响因素对水源跨区域联防联治有重要意义。利用淀山湖地区1984、1993、2006和2014年的遥感影像,通过修正生态系统服务价值当量因子,基于GIS空间分析技术对淀山湖地区1984—1993年、1993—2006年、2006—2014年土地利用变化及生态系统服务价值(Ecosystem Service Value, ESV)进行了分析。结果表明,淀山湖地区林地面积和建筑用地面总体呈增加趋势,而耕地面积和水体面积呈下降趋势。ESV结果显示,1984—2014期间水体ESV减少了2.15亿元,耕地的ESV减少了2.41亿元,林地的ESV增加了2.50亿元。各土地利用类型ESV敏感性指数均小于1,说明研究区生态系统服务价值是缺乏弹性的。在乡镇尺度,仅朱家角镇和锦溪镇ESV呈现净增长;在省市级尺度,江苏省境内的总土地单位面积ESV减少,而上海市境内的总土地单位面积ESV增加。驱动力分析表明,自然因素和社会经济因素均对ESV有影响,人口密度、区域总产值与ESV存在显著相关性。可见,土地利用方式的改变显著影响生态系统服务价值,合理的土地利用将有利于提高总土地单位面积生态系统服务价值。

Water resources are an important guarantee for the development of regions and cities.Understanding the changes in ecosystem services and their driving forces,therefore,is of great significance in the management of water resources across regions.By utilizing remote sensing images of Dianshan Lake area in 1984,1993,2006 and 2014,land-use change and ecosystem service value(ESV)were analyzed by revising the ESV coefficient of different types of land use.The results showed that the areas of woodland and construction land tended to increase,while those of arable land and water bodies tended to decrease between 1984 and 2014.Results from the ESV analysis showed that the ESV of water bodies and arable land decreased by 215 and 241 million yuan,respectively,while the ESV of woodland increased by 250 million yuan.The ESV sensitivity index of each land-use type was less than 1,indicating that the ESV of the study area was inelastic.On the township scale,the ESV analysis showed a net increase only in Zhujiajiao and Jinxi Towns.At the provincial and municipal scales,the total ESV perunitarea of Jiangsu Province decreased,while the total ESV per unit area of Shanghai increased.The driving force analysis showed that both natural and socio-economic factors had an impact on the ESV.Moreover,there was a significant correlation between population density and ESV and between total regional economic output and ESV.Our results suggest that changes in land use have an important impact on the ESV.An optimal land-use pattern would help to increase the total ESV across regions.