Abstract:

Scale effects on water and soil loss are trending topics and frontier issues in the fields of soil erosion, hydrology and water resources science, and even the whole field of geosciences. These issues have attracted extensive attention from many researchers in recent years. To fully understand the current research progress of the scale effects on water and soil loss in China, 776 related published papers, obtained from six electronic databases (i.e. CNKI, Wangfang, Weipu, Web of Science, Scopus, and ProQuest), were taken as the data source for review. Based on the approach of bibliometric analysis, the research profile, development history, research institutions, distribution of study area, and research methods were reviewed. Results showed that (1) the spatial scale effect on soil erosion and sediment delivery was the major concern, followed by the temporal scale effect on runoff and hydrology, while the time scale effect on soil erosion and sediment delivery, as well as the spatial scale effect on runoff and hydrology were relatively less or unsubstantially studied. (2) Regarding temporal scale distribution, inter-yearly scale predominated in the study of runoff and hydrology, and rainfall event scale predominated in the study of soil erosion and sediment delivery. Concerning spatial scale, small watershed scale and slope scale were the main scale. (3) A total of 240 research institutions participated in relevant research, of which the top five were: Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences (IGSNRR-CAS), Yellow River Conservancy Commission (YRCC), Northwest A&F University, Institute of Soil and Water Conservation, Chinese Academy of Sciences and Ministry of Water Resources (ISWC-CAS&MWR), and Beijing Normal University. (4) As for study areas, most studies clustered in Yellow River and Yangtze River regarding the river basin; the soil and water conservation zoning were dominated by the northwestern Loess Plateau, southwestern purple soil region, southern red soil region, and northern hilly and mountainous region; the terrain type was dominated by plateaus, undulating mountains and hills regarding; the climate zone was mainly studied in humid and semi-humid areas as well as in warm-temperate, sub-tropical, and mid-temperate zones. (5) Research methods were diverse and could be broadly divided into four categories: direct calculation, statistical analysis, model-based estimation, and simulated experiment; and there were 28 mathematical models involved in model-based estimation, in which the (R) USLE and SWAT had very extensive application. Possible development directions of future research include scale issues on flood, soil erosion, sediment delivery of extreme rainstorm events, water and soil loss underground in karst region, and hydrological and sediment connectivity, as well as variable-scale hydrological and erosion prediction models and multi-scale conversions of runoff and sediment data.

Key words: water and soil loss, runoff, sediment, temporal scale, spatial scale, bibliometric method, research progress, China

摘要：

水土流失尺度效应是当前土壤侵蚀领域、水文水资源科学乃至整个地学领域的热点和前沿问题。为了准确把握中国水土流失尺度效应研究进展,从国内外六大中英文论文数据库中获取了776篇相关研究文献作为综述的数据源。基于文献计量方法,从研究概况、发展历程、研究机构、研究区分布和研究手段等方面进行了综述。结果显示,（1）目前中国水土流失尺度效应研究以探讨侵蚀输沙的空间尺度效应为主,其次是径流水文的时间尺度效应,而关于侵蚀输沙的时间尺度效应和径流水文的空间尺度效应的研究则较为薄弱。（2）时间尺度分布上,径流水文研究以年际尺度为主,而侵蚀输沙研究多关注次降雨尺度。空间尺度分布上,以小流域和坡面尺度为主。（3）全国共有240家研究机构参与了相关研究,其中前五强单位依次是：中国科学院地理科学与资源研究所、水利部黄河水利委员会、西北农林科技大学、中国科学院水利部水土保持研究所和北京师范大学。（4）研究区的流域分布以黄河和长江为主;水土保持分区以西北黄土高原区、西南紫色土区、南方红壤区和北方土石山区居多;地形区分布以高原和起伏较大的山地丘陵为主;气候区分布湿润、半湿润区以及暖温带、亚热带和中温带居多。（5）研究方法多种多样,大致可分为直接计算、统计分析、模型估算和模拟试验这4类;其中模型估算中涉及到的数学模型共有28个,应用较多的有（R）USLE和SWAT。未来研究的可能发展方向有：极端暴雨事件洪水及其侵蚀输沙的尺度问题;喀斯特地区地下水土流失的尺度问题;水文泥沙连通性的尺度问题;变尺度水文-侵蚀-输沙预报模型;水沙数据多尺度转换。

关键词: 水土流失, 径流, 泥沙, 时间尺度, 空间尺度, 文献计量, 研究进展, 中国