基于InVEST模型的黄河流域产水量时空变化及其对降水和土地利用变化的响应

黄河流域是重要的水源涵养和生态屏障区,研究其水源供给服务对实现黄河流域高质量发展和生态环境保护具有重要意义。本研究基于InVEST模型和情景分析法,以土地利用覆被、气象及土壤等数据作为输入,分析了1995—2015年黄河流域产水量的时空格局以及降水变化和土地利用变化对流域产水量的影响,并探讨产水量对二者的响应。结果表明:1995—2015年,黄河流域产水深度增加,增量为24.34 mm,产水高值区集中在西部和西南部,低值区集中在西北区域,产水深度空间格局特征变化不明显;黄河流域三级流域中,龙羊峡以上流域产水量最高,约117 亿m³·a^-1,是黄河流域主要产水区,兰州至河口流域产水量最低,约0.44 亿m³·a^-1;整个流域中永久冰川及雪地的平均产水深度最大,草地是全流域产水总量的主要贡献地类,提供了总产水量的62.6%;降水对产水量的影响比较显著,土地利用/覆被变化对产水量的影响较小。

Spatio-temporal variation of water yield and its response to precipitation and land use change in the Yellow River Basin based on InVEST model

Yellow River Basin is an important water conservation and ecological barrier area, the study of water supply service in which is of great significance to the high-quality development and ecological environment protection. Based on the Invest InVEST model and the method of scenario analysis, we analyzed the temporal and spatial patterns of water yield in the Yellow River Basin in recent 20 years (1995-2015) with land use and cover, meteorological and soil data as inputs. We examined the impacts of precipitation change and land use change on water yield and their impacts on water yield. The results showed that water yield depth had average growth of 24.34 mm from 1995 to 2015. The high water yield area located in the west and southwest, and the low water yield area located in the northwest. The change of deep spatial pattern was not evident. Among the three grade basins in the Yellow River Basin, the river basin above Longyangxia, with the highest water yield of about 11.7 billion m³·a^-1, was the main water yield area of the Yellow River Basin. The river basin from Lanzhou to Hekou had the lowest water yield, with a value of 44 million m³·a^-1. The average water yield depth of permanent glacier and snow land was the largest in the whole basin. Grassland was the main contributor to the total water yield of the whole basin, providing 62.6% of the total water yield. Land use/cover change had moderate effect on water yield.