Natural and anthropogenic influences on the recent droughts in Yellow River Basin, China
Natural and anthropogenic influences on the recent droughts in Yellow River Basin, China
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自然和人为对黄河流域近期干旱的影响
DOI：
10.1016/j.scitotenv.2019.135428
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发表时间：
2020
影响因子：
9.8
通讯作者：
Farhan Saleem
中科院分区：
文献类型：
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作者：
Abubaker Omer;Ma Zhuguo;Zheng Ziyan;Farhan Saleem
人类主导环境中的干旱不能被视为一种单向的危害，因为其特征是由自然气候变异性和人类影响衍生和改变的。在这项研究中，我们应用观测建模框架，基于模拟和观测的黄河流域中国流域六个子流域的水文气象数据，量化了自然和人为对干旱特征的控制。采用定标土壤水分评价工具(SWAT)模拟自然情况，用标准化降水指数、径流干旱指数和土壤水分亏缺指数从气象、农业和水文三个方面表征干旱。在此基础上，运用多元相关分析、热图和多元回归线性模型等多种统计方法，建立了干旱特征与多种影响因子之间的统计关系。结果表明，降水干旱持续时间对农业干旱持续时间有重要影响，而水文干旱的严重程度和持续时间与土壤水分密切相关。气象-农业干旱传播机制主要受土地利用/土地覆盖变化(LULCC)的影响，而气象-水文传播主要受直接人类活动(DHA)的影响。人类改良剂对干旱的严重程度和持续时间既有积极的影响，也有消极的影响。例如，农业实践和植树造林加剧了土壤水分干旱，而草地恢复对农业干旱严重程度产生了积极影响。毁林加剧了水文干旱，而植树造林和草地恢复则相反。DHA在很大程度上放大了水文干旱的严重程度和持续时间，而灌溉返流则增加了干旱的持续时间。在空间上，城市化程度高的小流域和灌溉农田比以草地为主的小流域干旱时间短，严重程度低。
Drought in human-dominated environments cannot be seen as a unidirectional hazard as its characteristics are derived and modified by both natural climate variability and human influences. In this study, we applied an observation-modeling framework to quantify the natural and human controls on drought characteristics based on simulated and observed hydrometeorological data from six sub-catchments of the Yellow River Basin in China. A calibrated Soil and Water Assessment Tool (SWAT) was applied to simulate the naturalized situation, whereas Standardized Precipitation Index, Streamflow Drought Index, and Soil Moisture Deficit Index were used to characterize drought at meteorological, agricultural and hydrological aspects. Furthermore, various statistical tools, i.e., bivariate correlation analysis, heat maps, and linear models based on multiple regression, were applied to find the statistical relationships between drought characteristics and the multiple influencing factors. The results revealed that the duration of precipitation’s dry spells was important for agricultural drought duration, whereas hydrological drought severity and duration highly depended on soil moisture. Meteorological to agricultural drought propagation mechanism was primarily affected by land use/land cover change (LULCC), whereas meteorological to hydrological propagation was influenced mostly by direct human activities (DHA). The human modifiers were found to have both positive and negative effects on drought severity and duration. For instance, agricultural practices and afforestation intensified soil moisture drought, while grassland restoration had a positive impact on agricultural drought severity. Deforestation enhanced hydrological drought, while afforestation and grassland restoration had the opposite effect. Hydrological drought severity and duration were largely amplified by DHA but enhanced by irrigation return flow. Spatially, sub-catchments with high urbanization and irrigated cropland were found to have shorter and less severe droughts than those dominated by grassland.