为了评估流域土地利用变化对生态系统水量调节能力的影响,从生态水文的新角度来管理流域水资源,本文借助遥感、野外监测等方法获取地表基本参数,基于GIS技术与方法,以网格为基本单元,计算流域生态耗水量,评估太湖流域近25年土地利用变化对生态耗水的影响,结果表明:(1)近25年的年总耗水量高值区域主要分布在流域的浙西区、环太湖的北缘以及湖西区林木分布区,耗水量及其截留量、蒸散量等分量的空间分布特征基本和土地利用类型的植被覆盖度一致,耗水量较大值区域对应着植被覆盖度较高区域;(2)太湖流域1985~2000年以及2000~2010年耗水量显著减少的区域明显多于流域耗水量增多的区域,减少区域主要分布在浦东浦西区、苏锡常区和杭嘉湖区三大区域的建设用地的周围,多受建设用地扩张侵占了耕地的影响;(3)1985、2000、2010年年耗水量分别为1068.8、1041.5、960.2 mm,1985~2000年间的减小幅度(2.53%)明显小于2000~2010年间的幅度(7.78%),与太湖流域的近25年耕地面积1985~2000年减少程度(3.99%)和2000~2010年减少程度(11.09%)保持一致。
The effects of global land use / land cover changes(LUCC) on the ecosystem and environment have been widely concerned, e.g. IGBP / BAHC,MBP,MA has paid more and more attention to the effects of LUCC on ecosystem hydrological cycle. Ecological water consumption, an important part of surface water cycle, has been the hot spots in ecological hydrology. Taihu Lake Basin has endured a rapid land use and land cover changes with rapid development of socio-economic in recent 25 years, leading to degraded ecosystem function of water volume regulation, e.g. watershed flooding disasters occurred frequently. Aiming to provide an eco-hydrological management mode for the Taihu Lake Basin,the impact of land use and land cover changes on ecological water consumption in Taihu Lake Basin in recent 25 years was assessed by computing the water consumption elements at grid units by means of GIS platform. The basic surface parameters which were used for water balance calculation were obtained by Remote Sensing and field monitoring methods.The main conclusions were drawn as followed:(1)the spatial distribution of total annual ecological water consumption and its components(interception and evapotranspiration) were in good accordance with distribution of vegetation cover. The areas of higher water consumption corresponded to a higher degree of vegetation cover, which distributed in the southwest mountainous and hilly areas in west Zhejiang Province, the northern and western hills around Taihu Lake. The areas of the lower water consumption corresponded to the areas of the lower vegetation coverage, which distributed in Pudong and Puxi district in eastern Taihu Lake Basin; large, medium and small cities, villages and towns in Suzhou-Wuxi-Changzhou region. Interception and evapotranspiration with high value distributed mainly in the hills and mountains with the forest, i.e.west Zhejiang province, north and west areas around Taihu Lake.(2)From 1985 to 2000 and from 2000 to 2010 in Taihu Lake Basin, the areas of a significa