摘要
时空异质性的存在,使得水文研究结果表现出不确定性。由于异质性是尺度的函数,对于异质性的处理通常采用较小尺度以减小其影响,如在水文模型里对数据进行离散化,如何确定这一最小尺度以及尺度变化对结果产生怎样的影响,以上问题至今都还未得到完全解决。利用嫩江流域2000年土地利用数据,计算土地利用在不同尺度(网格大小为5km×5km、10km×10km和20km×20km)下的蒸散发量、空间异质性,并分析其空间分布变化。研究结果表明,不同尺度下土地利用类型与蒸散发异质性变化趋势相似;尺度变化对流域蒸散发量数值影响较小,但使其分布质心最终向着占地面积大的土地利用类型方向移动。
The results of hydrological study present uncertainty due to the existence of spatial and temporal heterogeneity. Downscaling is usually employed to decrease the impact of heterogeneity which is a function of scale, for example, discretization in hydrological model. However, it is a problem to confirm the smallest scale and how does it impact the results for scale changing. Perfect solutions to the problems above have not yet been found so far. The evapotranspiration and its spatial heterogeneity, distribution patterns were analyzed based on land use data in 2000 in Nenjiang River basin at various grid sizes （5km×5km, 10km×10km and 20km×20km）. The results show that there is a similar tendency of spatial heterogeneity in land use type and evapotranspiration at different scales, and a smaller influence of scale change on the evapotranspiration, by which the center of distribution patterns moving to the type of land use with larger area.
出处
《水利学报》
EI
CSCD
北大核心
2012年第12期1440-1446,共7页
Journal of Hydraulic Engineering
基金
国家自然科学基金(50779075)
国家创新群体项目(51021066)
国家“973”项目(21010CB951102)
关键词
土地利用
蒸散发量
网格大小
空间异质性
空间分布
land use
evapotranspiration
grid size
spatial heterogeneity
spatial patterns
