黄土高原半干旱区流域产水功能时空变化特征

    Characteristics of Spatial and Temporal Variations of Water Production Functions in the Semi-arid Watershed of the Loess Plateau

    • 摘要: 在气候变化和人类活动背景下研究产水量的时空特征和变化响应, 分析马莲河流域产水功能的时空分异特征和变化趋势, 对半干旱区域生态系统可持续发展具有重要意义。基于InVEST模型定量分析了1990-2020年马莲河流域产水量的时空变化特征和土地利用类型、海拔、降水和实际蒸散发等影响因素对产水量的影响。结果表明: (1)流域1990、2000、2010和2020年总产水量分别为4.563×108、2.640×108、3.853×108和3.264×108 m3, 30 a间流域产水空间格局基本一致, 总体呈下游高、上游低的空间分异特征; 流域产水深度以减少为主, 显著减少区集中于中上游, 极显著减少区主要在中下游。(2)城镇用地、建设用地和高覆盖度草地产水能力最强, 水域产水能力最弱; 降水越多、海拔越低、实际蒸散越小、植被覆盖度越低的区域产水能力越强。(3)产水量与降水量呈显著正相关, 与海拔、实际蒸散量呈负相关, 各影响因子对产水量的影响程度排序为降水量>高程>实际蒸散量>土地利用。(4)西南部作为产水功能重点功能区应加以规划保护, 东北部是产水低值区, 应减少人类活动以重点保护生态系统稳定和生物多样性。1990-2020年马莲河流域产水量时空格局变化显著, 降水因子是其主要驱动因子。

       

      Abstract: Under the background of climate and land use change, it is of great significance to study the spatial-temporal characteristics and response of water production and analyze the spatial-temporal differentiation and variation trend of water production function in the Malian River Basin. Based on InVEST model, the temporal and spatial characteristics of water yield and the effects of land use type, elevation, precipitation, and actual evapotranspiration on water yield in Malian River Basin from 1990 to 2020 were quantitatively analyzed. The results show that: (1) The total water yield of the basin in 1990, 2000, 2010 and 2020 was 4.563×108, 2.640×108, 3.853×108 and 3.264×108 m3, respectively. The spatial pattern of water yield in different periods was basically the same, showing the spatial difference characteristics of high in downstream and low in upstream; The depth of water produced in the whole basin is mainly reduced, the significant reduction area is concentrated in the middle and upper reaches, and the extremely significant reduction area is mainly in the middle and lower reaches. (2) The water production capacity of urban land, construction land and high coverage grassland was the strongest, while that of water area was the weakest. The higher the precipitation, the lower the altitude, the smaller the actual evapotranspiration and the lower the vegetation coverage, the stronger the water production capacity. (3) There was a significant positive correlation between water production and precipitation, and a negative correlation between altitude and actual evapotranspiration. The order of influence degree of each influencing factor on water production was precipitation > altitude > actual evapotranspiration > land use. (4) The southwest of the basin as a key functional area of water production should be planned for protection, while the northeast of the basin is a low-value area of water production, and human activities should be reduced to focus on protecting ecosystem stability and biodiversity. The spatial-temporal pattern of water production in the Malian River Basin changed significantly from 1990 to 2020, and the precipitation factor is the main driving factor.

       

    /

    返回文章
    返回