Department of Municipal and Environmental Engineering, Hebei University of Architecture, Zhangjiakou 075000, China; Hebei Key Laboratory of Water Quality Engineering and Comprehensive Utilization of Water Resources, Hebei University of Architecture, Zhangjiakou 075000, China.
Department of Municipal and Environmental Engineering, Hebei University of Architecture, Zhangjiakou 075000, China; Hebei Key Laboratory of Water Quality Engineering and Comprehensive Utilization of Water Resources, Hebei University of Architecture, Zhangjiakou 075000, China.
Sci Total Environ. 2022 Feb 25;809:151153. doi: 10.1016/j.scitotenv.2021.151153. Epub 2021 Oct 22.
Large-scale revegetation practices have lasted approximately two decades in the agro-pastoral ecotone of northern China (AENC), and their impacts on hydrological and ecological effects remain poorly understood. Previous studies largely focused on assessing water yield service (WYs) based on several fixed time points, whereas time series information-continuous WYs dynamics were more reliable and valuable in decision-making about water sustainability goals. This study analyzed the interannual WYs trend and relative roles of its drivers in the last 20 years based on a newly proposed approach, and revealed the past, present and future impacts of revegetation on WYs. The final results indicated that the annual WYs averaged approximately 97 mm and exhibited an increasing trend of 1.96 mm year (p = 0.086) during 2000-2019, in which climate and land-use changes were responsible for 88% and 12% of WYs variations, respectively. From 2000 to 2019, WYs was pronouncedly 1.47 mm year (p = 0.119) lower in the afforestation area than in the nonafforestation area, but the precipitation in the two regions had a statistically insignificant difference (p = 0.97). Future revegetation scenarios showed great potential for the shrinkage of WYs provision, even approaching a maximum of 50 mm at a local scale. Even so, the afforestation-induced reductions in blue water and benefits in green water both should receive equal attention. Specifically, any attempts to assess WYs or other climate-driven ecosystem services using discontinuous years as the study period must be taken with extreme caution.
在中国北方农牧交错带（AENC），大规模的植被恢复实践已经持续了大约二十年，但其对水文和生态效应的影响仍知之甚少。以前的研究主要集中在基于几个固定时间点评估水产量服务（WYs）上，而时间序列信息——连续的 WYs 动态在水可持续性目标的决策中更可靠和有价值。本研究基于一种新提出的方法分析了过去 20 年的年际 WYs 趋势及其驱动因素的相对作用，并揭示了植被恢复对 WYs 的过去、现在和未来影响。最终结果表明，年平均 WYs 约为 97mm，在 2000-2019 年间呈增加趋势，为 1.96mm 年（p=0.086），其中气候和土地利用变化分别对 WYs 变化的 88%和 12%负责。从 2000 年到 2019 年，造林区的 WYs 比非造林区低 1.47mm 年（p=0.119），但两地区的降水量差异无统计学意义（p=0.97）。未来的植被恢复情景表明，WYs 供应的收缩潜力巨大，即使在局部范围内接近 50mm 的最大值。即便如此，造林导致的蓝水减少和绿水增加都应该得到同等关注。具体来说，使用不连续年份作为研究期来评估 WYs 或其他气候驱动的生态系统服务必须极其谨慎。
