Combining downscaled-GRACE data with SWAT to improve the estimation of groundwater storage and depletion variations in the Irrigated Indus Basin (IIB)
Combining downscaled-GRACE data with SWAT to improve the estimation of groundwater storage and depletion variations in the Irrigated Indus Basin (IIB)
复制标题
将缩小比例的 GRACE 数据与 SWAT 相结合，改进对印度河灌溉盆地 (IIB) 地下水储量和枯竭变化的估计
DOI：
10.1016/j.scitotenv.2022.156044
复制
发表时间：
2022
影响因子：
9.8
通讯作者：
Ahmad, Bashir
中科院分区：
文献类型：
--
作者：
Arshad, Arfan;Mirchi, Ali;Samimi, Maryam;Ahmad, Bashir
农业生产系统的增长是全球地下水枯竭的主要驱动力。平衡地下水供应和粮食生产需要当地了解地下水储存和消耗的变化，以应对不同的种植系统和地表水灌溉的可用性。虽然重力恢复和气候实验（GRACE）的进展，促进了估计地下水储量（GWS）的变化，在最近几年，粗糙的分辨率的GRACE数据阻碍了GWS变化热点的表征。在这里，我们提出了一种新的空间水平衡方法，以提高分布式估计地下水储存和消耗的变化在空间尺度上，可以检测到的热点GWS变化。利用混合地理加权回归（MGWR）模型，将GRACE Level-3数据从粗分辨率（1° × 1°）降维到基于高分辨率环境变量的细尺度（1 km × 1 km）。然后，我们结合了缩小规模的GRACE为基础的GWS变化与校准的土壤和水评估工具（SWAT）模型的结果。我们证明了应用程序的方法在灌溉印度河流域（IIB）。2002年至2019年期间，IIB的55个运河指挥区的地下水储量损失总额各不相同，在Dehli Doab观察到的损失最高，超过50 km 3，其次是上游的7.8-49 km 3，下游的运河指挥区为0.77-7.77 km 3。Dehli Doab的GWS下降了-325.55毫米/年，其次是BIST Doab的-186.86毫米/年，巴里Doab的-119.20毫米/年，以及JECH Doab的-100.82毫米/年。在德里Doab和BIST Doab的运河指挥区，地下水枯竭率正在以每年0.21-0.35米的速度增加。一些运河指挥区的地下水消耗量更大（例如，RACHNA、BIST Doab和Delhi Doab）与稻麦种植制度、低降雨量和支流流量低有关。
The growth of agricultural production systems is a major driver of groundwater depletion worldwide. Balancing groundwater supply and food production requires localized understanding of groundwater storage and depletion variations in response to diverse cropping systems and surface water availability for irrigation. While advances through Gravity Recovery and Climate Experiment (GRACE) have facilitated estimating the groundwater storage (GWS) changes in recent years, the coarse resolution of GRACE data hinders the characterization of GWS variation hotspots. Herein, we present a novel spatial water balance approach to improve the distributed estimation of groundwater storage and depletion changes at a spatial scale that can detect the hotspots of GWS variation. We used a mixed geographically weighted regression (MGWR) model to downscale GRACE Level-3 data from coarse resolution (1° × 1°) to fine scale (1 km × 1 km) based on high resolution environmental variables. We then combined the downscaled GRACE-based GWS variations with results from a calibrated Soil and Water Assessment Tool (SWAT) model. We demonstrate an application of the approach in the Irrigated Indus Basin (IIB). Between 2002 and 2019, total loss of groundwater reserves varied in the IIB's 55 canal command areas with the highest loss observed in Dehli Doab by >50 km3followed by 7.8–49 km3in the upstream, and 0.77–7.77 km3in the downstream canal command areas. GWS declined by −325.55 mm/year at Dehli Doab, followed by −186.86 mm/year at BIST Doab, −119.20 mm/year at BARI Doab, and −100.82 mm/year at JECH Doab. The rate of groundwater depletion is increasing in the canal command areas of Delhi Doab and BIST Doab by 0.21–0.35 m/year. Larger groundwater depletion in some canal command areas (e.g., RACHNA, BIST Doab, and Delhi Doab) is associated with the rice-wheat cropping system, low rainfall, and low flows from tributaries.