2011—2019年宁夏土壤侵蚀动态变化及分布特征

宁夏是黄河流域生态保护和高质量发展的先行区,掌握其土壤侵蚀动态变化对于黄河流域的生态修复具有重要意义。本研究根据宁夏水土保持公报数据,对2019年宁夏土壤侵蚀强度、面积和空间分布进行分析,并与2011年的侵蚀状况进行对比,获得宁夏土壤侵蚀的动态变化特征。结果表明:①2019年宁夏回族自治区的土壤侵蚀总面积为15888.51 km2,占全区土地总面积的23.93%,与2011年相比,侵蚀面积共减少了19.02%。②中卫市的土壤侵蚀面积较大,且侵蚀强度较高;与2011年相比,各市的土壤侵蚀总面积都有不同程度的减少,且侵蚀强度总体都有所下降。③土壤侵蚀主要集中分布在Ⅲ丘陵台地干旱草原风水蚀交错区和Ⅶ黄土丘陵沟壑水风蚀交错区。④不同土地利用类型下的土壤侵蚀面积和强度有一定差异,建设用地和交通运输用地的侵蚀强度较大。     

水蚀风蚀交错带生态环境演变监测研究方法

围绕神木水蚀交错带土壤侵蚀与生态环境演变关系及其整治这一课题，着重讨论系统定位监测研究内容和方法，以典型调查与定位观测相结合，分析研究该地区的气候，风蚀水蚀特征及其生态环境演变过程。     

Geoinformation mapping of soil erosion in the Middle Volga region

The results of a medium-scale geoinformation mapping of soil erosion on an area of about 150000 km² in the Middle Volga region are analyzed using the catchment-based approach. A quantitative index of the development of soil erosion on the agricultural lands is suggested. It reflects the intensity of soil erosion on slopes within the river catchments. A computer-based vector map of the boundaries of 3331 elementary catchments has been developed. It represents the territorial units for the analysis of soil erosion. Archive materials from the former institutes for land survey have been used to compile a series of the maps of soil erosion in river catchments on a scale of 1: 200000. The zoning of erosional processes has been performed, and the natural and anthropogenic levels of soil erosion in different basins have been estimated. The analysis of these materials shows that the topography and agricultural activity of humans are the major factors controlling the development of erosion. The maximum development of soil erosion in the studied region is typical of the subzone of broadleaved forests.     

贵州高原水土流失及其影响因素研究

在利用遥感技术编制贵州省土壤侵蚀图的基础上,阐述了贵州省不同级别水土流失强度分布状况,水土流失在危险程度及水土流失强度分区;分析了贵州高原流失产生的自然背景与影响因素;并根据贵州高原的特点提出了治理保护的战略措施。     

Tillage and water erosion on different landscapes in the northern North American Great Plains evaluated using Cs technique and soil erosion models

Total soil erosion is the integrated result of all forms of soil erosion — wind, water and tillage. It has been recognized that in topographically complex landscapes, individual soil erosion processes and their interactions all contribute towards total soil erosion. In this study, two field sites, representing different landscapes in the northern region of the North American Great Plains, were examined. Water and tillage erosions were estimated using the established water and tillage erosion models and total soil erosion was estimated using the ¹³⁷Cs technique.We determined that the patterns of water and tillage erosion across the landscapes are mainly dependent on topographic features and they are fundamentally different within topographically complex landscapes. On the slope of undulating landscapes, tillage and water erosion both contribute considerably to total soil erosion. On the knoll of hummocky landscapes, tillage erosion dominates the pattern of total soil erosion. Tested against the Cs measurements, the patterns of total soil erosion cannot be well estimated by water or tillage erosion model alone unless one of the two erosion processes predominate over the other erosion processes. Combining water and tillage erosion models generally provides better estimations of total soil erosion than the component models on their own. Most soil properties and crop yield were found to be closely correlated with total soil erosion. For a given erosion process, the soil erosion patterns estimated using different models with reasonable parameter settings were similar to each other. However, it is necessary to choose an optimal model and to obtain accurate parameters for the purpose of accurate assessments of the erosion rates.     

辽宁土壤侵蚀状况分区与防治重点

通过对史料研究,阐述了辽宁土壤侵蚀发展的3个阶段,即初始阶段,加速阶段和初步控制阶段,并运用以往的研究资料和最新的遥感普查资料对全省的土壤侵蚀进行了分区,在此基础上提出了各侵蚀区的防治重点,这些都将为土壤侵蚀的防治工作提供重要的科学依据。     

子午岭林区土壤侵蚀与生态环境关系的研究内容和方法

围绕子午岭天然次生林区土壤侵蚀与生态环境演变关系的研究主题,着重讨论研究背景,研究内容和研究方法。以典型调查和定位观测相结合,分析研究植被的破坏与恢复对土壤侵蚀的影响。通过建立大型径流场,动态监测不同地形部位林地与开垦地的土壤侵蚀演变过程,包括降雨、径流、入渗和侵蚀量的变化,细沟侵蚀和浅沟侵蚀的演变,土壤侵蚀与土壤退化的演变,坡、沟侵蚀的演变;同时结合进行野外人工降雨试验,林地和开垦地小气候对比观测等。初步建立了一整套宏观与微观相结合的研究体系,在黄土高原残留林区建立了土壤侵蚀与生态环境观测站,填补了国内空白。     

自动化监测系统在水土流失观测中的引进与应用

由于土壤侵蚀使土壤退化及土地生产力下降,甚至威胁人类生产生活的生态环境.多年来土壤侵蚀规律研究一直是自然科学领域研究的关键性技术.20世纪50年代初,黄委会在黄土丘陵沟壑区第1副区设立了小流域土壤侵蚀不同类型的因子观测站网、径流小区等,采集获得60 a多的原始观测资料.长期以来一直为人工观测,成果资料多为降雨-径流-泥沙的特征点源数据,而每次降雨侵蚀是一个连续的自然过程,人工监测由于其因子对位性、监测数据的连续性和系统性较差,造成研究成果只局限于土壤侵蚀影响的单因子或部分因子研究成果,严重影响该区水土流失系统模型的开发.为了进一步提升水土流失规律研究的水平,寻找土壤侵蚀客观真实的自然数据规律,加快该区水土流失模型开发,在该区引进了现代自动化的水土流失监测系统,经过2 a的监测实践和成果数据的比测分析,不仅节约了大量的人、才物资源,而且获取得了客观真实、精度较高和连续动态的水土流失过程数据,对该区水土流失规律研究将起到积极的推动作用.     

宁强县土壤侵蚀的地貌分布特征

为了揭示宁强县土壤侵蚀的空间分布特征,利用GIS技术,通过对宁强县土壤侵蚀强度分布图和DEM图的叠加,得到土壤侵蚀强度在坡度、坡向、高程、起伏度等地貌因子的分布特征。结果显示,宁强县水土流失程度为63.79%,土壤侵蚀强度以中度为主。不同坡度、高程、起伏度下的水土流失面积比例、土壤侵蚀综合指数和土壤侵蚀强度分别随着坡度增加、高程升高、起伏度上升呈先增大后减小的单峰分布趋势。平地的水土流失面积比例接近0,不同坡向的水土流失面积比例、土壤侵蚀综合指数和土壤侵蚀强度分布差异不显著。不同土壤侵蚀强度的最大值和分布范围均随着坡度的增加而增大,但却随着高程的升高而减小。各土壤侵蚀强度的起伏度分布均很相似。此结论可为区域水土保持规划和水土流失治理提供决策依据和理论支持。     

基于RUSLE的松花江流域不同侵蚀类型区泥沙输移比估算

为摸清东北黑土区土壤侵蚀与泥沙输移特征,以松花江流域为研究对象,选取不同侵蚀类型区8个水文站控制区,利用RUSLE模型,结合水文站实测输沙数据,分析了不同侵蚀类型区泥沙输移比的时空变化特征。结果表明:（1）松花江流域各侵蚀类型区均以微度侵蚀和轻度侵蚀为主,而草地、旱地和裸地侵蚀模数均呈现依次增大趋势,且大于该区容许土壤流失量,特别是松岭站、碾子山站、大石寨站和大山咀子站水文站控制区裸地土壤侵蚀模数均大于20 000 t/（km²·a）,达到剧烈侵蚀程度。不同侵蚀类型区之间侵蚀模数表现为丘陵沟壑区Ⅰ > 丘陵沟壑区Ⅱ > 天然林区 > 漫川漫岗区。（2）松花江流域不同侵蚀类型区泥沙输移比总体上表现为漫川漫岗区 > 丘陵沟壑区Ⅱ > 丘陵沟壑区Ⅰ > 天然林区。（3）同一侵蚀类型区不同年际间泥沙输移比波动起伏,而从20世纪60年代到80年代,人类活动影响较小的天然林区和丘陵沟壑区Ⅱ不同时期平均泥沙输移比相差不大,人类活动剧烈的漫川漫岗区和丘陵沟壑区Ⅰ平均泥沙输移比则表现为波动式递增。研究结果对于了解东北黑土区土壤侵蚀和泥沙输移规律,明确该区域土壤侵蚀机理和治理目标具有指导意义。