State Key Laboratory of Soil Erosion and Dryland Farming on the Loess Plateau, Institute of Soil and Water Conservation, Chinese Academy of Science and Ministry of Water Resources, Yangling 712100, China; University of Chinese Academy of Science, Beijing 100049, China.
College of Resources and Environment, Huazhong Agricultural University, Wuhan 430070, China.
Sci Total Environ. 2020 Sep 15;735:139517. doi: 10.1016/j.scitotenv.2020.139517. Epub 2020 May 19.
Anthropogenic pressure coupled with high rainfall and diverse heterogeneous landscapes (e.g., land use and topography) has resulted in severe water erosion in the red soil hilly region (RSHR) of China. Soil and water conservation measures (SWCMs) have been extensively implemented, and their effects on runoff and sediment control have been widely tested at plot scales. However, it is difficult to gain an overview of the efficiency of SWCMs due to the difficulty of directly upscaling field observations to regional scales. We conducted a meta-analysis of 498 field plots covering 53 sites in the RSHR to evaluate the efficiency of different SWCMs and identify optimal conservation practices. The results were as follows: (i) SWCMs involving erosion control (92%) had a greater efficiency than those focusing on runoff reduction (73%). (ii) The implementation of combined measures was more effective than single measures for reducing runoff and soil loss. (iii) All thirty SWCMs showed a significant effect with respect to runoff and sediment control, except for contour tillage effect on reduction of soil loss. (iv) The maximum and minimum ratios between runoff and sediment reduction were found in orchard and cropland, respectively. (v) Six measures, mulching, tree crop + grass, tree crop + hedgerows, tree crop + grass cover + terrace, tree crop + hedgerows + terrace and hedgerows + contour tillage, can be recommended as high effective SWCMs in the RSHR. This study provides a systematic overview quantifying the factors controlling the effectiveness of SWCMs in the RSHR and can serve as a scientific foundation enabling decision makers to implement suitable SWCMs in mitigating land degradation due to water erosion.
人为压力加上高降雨量和多样化的非均质地貌（例如土地利用和地形）导致中国红壤丘陵区（RSHR）发生严重的水蚀。已广泛实施水土保持措施（SWCMs），并在小区尺度上广泛测试了其对径流和泥沙控制的效果。但是，由于难以将田间观测直接扩展到区域尺度，因此很难全面了解 SWCMs 的效率。我们对 RSHR 中 53 个地点的 498 个野外小区进行了荟萃分析，以评估不同 SWCMs 的效率并确定最佳保护实践。结果如下：（i）涉及侵蚀控制的 SWCMs（92％）比侧重于减少径流的 SWCMs（73％）效率更高。（ii）与单一措施相比，综合措施在减少径流和土壤流失方面更为有效。（iii）除了等高耕作对减少土壤流失的作用外，所有 30 种 SWCMs 对径流和泥沙控制均有显著作用。（iv）在果园和耕地中发现了径流和泥沙减少的最大和最小比值。（v）推荐了六种措施，即覆盖物，果树林+草，果树林+树篱，果树林+草覆盖+梯田，果树林+树篱+梯田和树篱+等高耕作，作为 RSHR 中高效的 SWCMs。本研究系统地概述了控制 RSHR 中 SWCMs 有效性的因素，可以为决策者提供科学依据，以实施适合的 SWCMs 来减轻水蚀引起的土地退化。
