无定河流域生境质量时空变化及预测

Spatio-temporal variation and prediction of habitat quality in Wuding River Basin

“十四五”规划提出将黄土高原作为重点纳入黄河重点生态区生态保护和修复重大工程,计划因地制宜实施小流域综合治理。无定河是黄土高原生态脆弱的典型流域,探究其生境质量时空变化对推动区域生态环境质量提升具有重要意义。从全流域和子流域尺度评价并预测了无定河流域生境质量时空演变特征,探究了生境质量空间分异驱动因子。结果表明:(1)2000—2020年,无定河流域林草占比增长了11.73%,建设用地面积比2000年增加了1倍多,未利用地面积占比减少了8.46%;2020—2050年,土地利用变化情况同2000—2020年基本保持一致,但变化强度逐步减弱。(2)2000—2020年,无定河流域生境质量逐期增加,整体呈小幅上升趋势;2020—2050年,流域生境质量水平增幅放缓,变化强度也随之减弱,总体向好发展。(3)土地利用方式是影响生境质量的主导因素,植被和土壤特征次之。

The"14th Five-Year Plan"of China proposed to include the Loess Plateau as a key area in the ecological protection and restoration of the Yellow River,implementing integrated watershed management on an appropriate basis.As a typical vulnerable basin in the Loess Plateau,the study of its spatial and temporal changes in habitat quality is of great significance for promoting the improvement of regional ecological environment quality.This study evaluated and predicted the spatiotemporal evolution characteristics of habitat quality in the Wuding River basin at both the whole basin and sub-basin scales,and explored the driving factors of spatial differentiation in habitat quality.The results showed that:(1)During 2000-2020,the proportion of forests and grasslands in the Wuding River basin increased by 11.73%,the area of construction land more than doubled compared to 2000,and the proportion of unused land decreased by 8.46%.During 2020-2050,the land use change situation is expected to remain consistent with the period from 2000 to 2020,but the intensity of change will gradually decrease.(2)During 2000-2020,the habitat quality in the Wuding River basin increased over time,showing a small upward trend overall.During 2020-2050,the growth rate of habitat quality will slow down,and the intensity of change will also weaken,indicating a generally positive development.(3)Land use is the dominant factor driving habitat quality,followed by NDVI and soil type.The study results can provide reference for biodiversity conservation,natural environment protection,and sustainable development in the basin.