半干旱地区水土流失因素的定量分析——以甘肃中部半干旱地区祖历河流域为例

本文从地貌演化角度,探讨了土壤侵蚀过程的动力学机理。认为土壤侵蚀过程受控于内力和外力两种营力过程及人类活动过程的共同作用。在内力相对稳定的时期内,土壤侵蚀过程主要依靠外力过程和人类活动过程共同完成;水力侵蚀是半干旱地区土壤侵蚀的主要方式之一,影响土壤侵蚀的外力因素主要是流量与降水。笔者以甘肃中部半干旱地区祖历河流域为例,运用灰色系统理论的灰色关联分析方法为手段,研究揭示了输沙量流量与降水指标之间的关系,提出了半干旱地区水土流失过程的产流、产沙函数,由此导出了水土流失因素定量分析的数学模型,并分析了祖历河流域五十年代初期至八十年代中期,人类活动对减水、减沙效益的贡献。     

内蒙古土壤侵蚀灾害研究

土壤侵蚀对环境越来越严重的危害已经引起世界各地广泛的注意；内蒙古自治区土壤侵蚀灾害亦成为制约本区农牧业经济发展的主要因素。本文论述了内蒙古土壤侵蚀灾情、分布规律、危害的种种表现，并对各旗县土壤侵蚀灾害作了定量评价，分析了土壤侵蚀灾害的形成原因。     

内蒙古清水河县土壤侵蚀灾害与防灾减灾对策

土壤侵蚀是一种非突发性的灾害。本文根据小流域库坝泥沙资料、坡度计算和TM、RBV(1:10万)影象,定量地研究了内蒙古清水河县土壤侵蚀。提出防治土壤侵蚀、发展区域经济的有效措施。     

宁南黄土丘陵区土壤侵蚀与水土保持

<正> 1.土壤侵蚀概况宁南黄土丘陵区位于黄河流域中上游,为中国黄土高原的一部分,面积约1.5万平方公里,年平均气温5—8℃,降水量300-500毫米,70%集中于6-9月份,且多以暴雨形式降落,蒸发量1340-1750毫米,属于内陆半干旱气候带。土壤侵蚀严重,重度土壤侵蚀面积占52%,侵蚀模数3000-10000吨/年·平方公里,年平均进入河道的泥沙量约1亿吨。黄土丘陵区土壤侵蚀是影响农林牧业生产发展的主要障碍因素。     

黄土坡面土壤侵蚀过程试验研究

采用人工模拟降雨的方法对黄土坡面土壤侵蚀过程进行了试验研究,取得了如下结果:①坡面土壤侵蚀随降雨过程的变化可用幂函数相关方程进行描述,15 m in和35 m in是土壤侵蚀强度随降雨过程变化的转折点;②雨强对坡面土壤侵蚀的影响可用幂函数相关方程进行描述,随着坡度的增大,土壤侵蚀强度随雨强的增大而增加的趋势更明显;③坡度对土壤侵蚀的影响可用抛物线相关方程进行描述,土壤侵蚀强度变化的临界坡度在25°附近;④坡长对土壤侵蚀的影响大体可用幂函数相关方程进行描述,但坡长对土壤侵蚀强度的影响比较复杂,随雨强大小的变化而表现为不同的形式;⑤坡度、坡长及雨强对坡面土壤侵蚀的综合影响可用多元线性相关方程进行描述,雨强对土壤侵蚀强度的影响远大于坡长及坡度因子,且坡度与土壤侵蚀强度的关系较坡长为密切。     

干旱区风蚀的防治

土壤侵蚀指在水和风这两种主要的自然力作用下土壤颗粒发生位移及其被输送到别处的过程,但对一特定地点的土壤侵蚀,往往很难确定水与风以何为主。一般说来,风蚀是一个长期的逐渐搬运的过程,而水蚀则往往来得非常迅速,给人留下深刻印象。事实上,直到本世纪初以前的长时间里,人们普遍认为水是土壤侵蚀的主要动因。相应对风则缺乏足够的认识。对风     

内蒙古锡林郭勒盟太仆寺旗土壤侵蚀初步分析

本文以内蒙古锡林郭勒盟太仆寺旗为研究区域,在全面获取图形资料和文字资料的基础上,应用美国通用土壤流失方程(USLE模型)和风蚀相对模型分别建立太仆寺旗土壤水力侵蚀模型和风力侵蚀模型,并根据实际情况确立了模型中各参数值,预测了太仆寺旗土壤侵蚀情况,从而为阴山北麓地区土壤侵蚀的分析预测提供科学依据。     

内蒙古东部地区土地利用与土壤侵蚀

内蒙古东部地区是自治区大农业生产的基地,与年俱增的人口压力导致土地利用强度增加和土壤侵蚀加速防治加速。防治加速土壤侵蚀要从合理的土地利用入手。     

典型黑土区坡耕地土壤侵蚀对土壤有机质和氮的影响

基于对黑土区松花江流域东山沟小流域坡耕地耕层土壤有机质、全氮和碱解氮含量及土壤侵蚀速率的分析,研究了坡耕地土壤侵蚀强度与土壤有机质、氮素含量的相关性及坡面侵蚀、沉积对土壤有机质和氮素空间分布的影响。结果表明,土壤侵蚀强度在流域分布呈现上游＞中游＞下游;土壤侵蚀强度沿坡面分布呈现出较弱—强—弱的变化趋势,存在明显的侵蚀强弱交替变化规律。小流域土壤有机质和氮素含量空间分布特征与土壤侵蚀强度分布特征相对应,表现为流域上游＜中游＜下游;三种土壤养分沿坡长分布呈现较高—低—高的变化趋势。土壤侵蚀速率与土壤有机质、全氮含量之间呈极显著负相关关系,与碱解氮含量存在显著负相关关系,证实了土壤侵蚀是影响我国东北典型黑土区土壤质量下降最重要因素。     

基于RS和GIS的内蒙古达里诺尔湖1999-2010年动态监测

近10年来干旱和半干旱地区的内陆湖泊发生了巨大变化,有的稳定、有的萎缩,有的消失。文中以多时相LandSat TM/ETM+影像和早期1:5万地形图为数据源,选择内蒙古地区第二大湖泊达里诺尔为研究区域,从面积、变化率和空间分异特征等多个方面对该湖泊近12年的变化过程进行分析。结果表明:达里诺尔湖从1999年到2010年湖泊重心西移岸线的发育系数减小,面积由220.3389km2缩减到190.0944km2,面积缩减了30.2445km2,年平均变化率为-0.012479%;对邻近三个气象台站50年气象资料的分析表明,湖泊萎缩的主要因素是气温的升高,蒸发量的上升以及降水量的减少。     

Research on wind erosion processes and controlling factors based on wind tunnel test and 3D laser scanning technology

The study of wind erosion processes is of great importance to the prevention and control of soil wind erosion. In this study, three structurally intact soil samples were collected from the steppe of Inner Mongolia Autonomous Region, China and placed in a wind tunnel where they were subjected to six different wind speeds (10, 15, 17, 20, 25, and 30 m/s) to simulate wind erosion in the wind tunnel. After each test, the soil surfaces were scanned by a 3D laser scanner to create a high-resolution Digital Elevation Model (DEM), and the changes in wind erosion mass and microtopography were quantified. Based on this, we performed further analysis of wind erosion-controlling factors. The study results showed that the average measurement error between the 3D laser scanning method and weighing method was 6.23% for the three undisturbed soil samples. With increasing wind speed, the microtopography on the undisturbed soil surface first became smooth, and then fine stripes and pits gradually developed. In the initial stage of wind erosion processes, the ability of the soil to resist wind erosion was mainly affected by the soil hardness. In the late stage of wind erosion processes, the degree of soil erosion was mainly affected by soil organic matter and CaCO₃ content. The results of this study are expected to provide a theoretical basis for soil wind erosion control and promote the application of 3D laser scanners in wind erosion monitoring.     

Interactive effects of wind speed,vegetation coverage and soil moisture in controlling wind erosion in a temperate desert steppe,Inner Mongolia of China

The rapid desertification of grasslands in Inner Mongolia of China poses a significant ecological threaten to northern China. The combined effects of anthropogenic disturbances(e.g., overgrazing) and biophysical processes(e.g., soil erosion) have led to vegetation degradation and the consequent acceleration of regional desertification. Thus, mitigating the accelerated wind erosion, a cause and effect of grassland desertification, is critical for the sustainable management of grasslands. Here, a combination of mobile wind tunnel experiments and wind erosion model was used to explore the effects of different levels of vegetation coverage, soil moisture and wind speed on wind erosion at different positions of a slope inside an enclosed desert steppe in the Xilamuren grassland of Inner Mongolia. The results indicated a significant spatial difference in wind erosion intensities depending on the vegetation coverage, with a strong decreasing trend from the top to the base of the slope. Increasing vegetation coverage resulted in a rapid decrease in wind erosion as explained by a power function correlation. Vegetation coverage was found to be a dominant control on wind erosion by increasing the surface roughness and by lowering the threshold wind velocity for erosion. The critical vegetation coverage required for effectively controlling wind erosion was found to be higher than 60%. Further, the wind erosion rates were negatively correlated with surface soil moisture and the mass flux in aeolian sand transport increased with increasing wind speed. We developed a mathematical model of wind erosion based on the results of an orthogonal array design. The results from the model simulation indicated that the standardized regression coefficients of the main effects of the three factors(vegetation coverage, soil moisture and wind speed) on the mass flux in aeolian sand transport were in the following order: wind speedvegetation coveragesoil moisture. These three factors had different levels of interactive effects on the mass flux in aeolian sand transport. Our results will improve the understanding of the interactive effects of wind speed, vegetation coverage and soil moisture in controlling wind erosion in desert steppes, and will be helpful for the design of desertification control programs in future.     

An estimation method of soil wind erosion in Inner Mongolia of China based on geographic information system and remote sensing

Studies of wind erosion based on Geographic Information System(GIS) and Remote Sensing(RS) have not attracted sufficient attention because they are limited by natural and scientific factors.Few studies have been conducted to estimate the intensity of large-scale wind erosion in Inner Mongolia,China.In the present study,a new model based on five factors including the number of snow cover days,soil erodibility,aridity,vegetation index and wind field intensity was developed to quantitatively estimate the amount of wind erosion.The results showed that wind erosion widely existed in Inner Mongolia.It covers an area of approximately 90×104 km2,accounting for 80% of the study region.During 1985–2011,wind erosion has aggravated over the entire region of Inner Mongolia,which was indicated by enlarged zones of erosion at severe,intensive and mild levels.In Inner Mongolia,a distinct spatial differentiation of wind erosion intensity was noted.The distribution of change intensity exhibited a downward trend that decreased from severe increase in the southwest to mild decrease in the northeast of the region.Zones occupied by barren land or sparse vegetation showed the most severe erosion,followed by land occupied by open shrubbery.Grasslands would have the most dramatic potential for changes in the future because these areas showed the largest fluctuation range of change intensity.In addition,a significantly negative relation was noted between change intensity and land slope.The relation between soil type and change intensity differed with the content of Ca CO3 and the surface composition of sandy,loamy and clayey soils with particle sizes of 0–1 cm.The results have certain significance for understanding the mechanism and change process of wind erosion that has occurred during the study period.Therefore,the present study can provide a scientific basis for the prevention and treatment of wind erosion in Inner Mongolia.     

农牧交错带土地退化类型区的划分及其防治研究

本文在研究阴山北麓地区环境背景的基础上 ,从自然因素、土地利用因素、社会经济因素及土地退化程度因素中选出 2 3个指标变量 ,首先运用主成分分析的数学方法 ,将该区划分为 3个不同的土地退化类型区 ,分别为半干旱农业为主区 ,半干旱牧业为主区 ,和干旱牧业为主区。其次、根据土地退化评价体系对该区退化土地进行了评价研究。最后在评价的基础上 ,将阴山北麓地区细分为 5个土地退化类型区 ,分别为干旱牧农结合中度风蚀沙化丘陵区 ,半干旱农牧结合极强度风蚀沙化丘陵区 ,半干旱农业为主强度风蚀沙化滩川平原区 ,半干旱林牧农结合中度水蚀山地 ,半干旱牧业为主强度风蚀沙化高平原区。最后对不同的土地退化类型区根据各区地形地貌特征、土地退化类型、土地退化程度、自然资源状况、生态经济条件和经济发展趋势的相似性 ,结合环境综合治理方案 ,以保持乡 (镇 )行政区划的完整性为原则将该区又划分为四个生态经济类型区 ,即丘陵防风固沙牧、林、农结合区 ,滩川地农牧结合区 ,山地水土保持林、牧结合区和高平原防风固沙牧业为主区 ,在此基础上提出了土地退化防治分区整治途径。     

An experimental study on the influences of wind erosion on water erosion

In semi-arid regions, complex erosion resulted from a combination of wind and water actions has led to a massive soil loss and a comprehensive understanding of its mechanism is the first step toward prevention of the erosion. However, the mutual influences between wind erosion and water erosion have not been fully understood. This research used a wind tunnel and two rainfall simulators and simulated two rounds of alternations between wind erosion and water erosion(i.e., 1~(st) wind erosion–1~(st) water erosion and 2~(nd) wind erosion–2~(nd) water erosion) on three slopes(5°, 10°, and 15°) with six wind speeds(0, 9, 11, 13, 15, and 20 m/s) and five rainfall intensities(0, 30, 45, 60, and 75 mm/h). The objective was to analyze the influences of wind erosion on succeeding water erosion. Results showed that the effects of wind erosion on water erosion were not the same in the two rounds of tests. In the 1~(st) round of tests, wind erosion first restrained and then intensified water erosion mostly because the blocking effect of wind-sculpted micro-topography on surface flow was weakened with the increase in slope. In the 2~(nd) round of tests, wind erosion intensified water erosion on beds with no rills at gentle slopes and low rainfall intensities or with large-size rills at steep slopes and high rainfall intensities. Wind erosion restrained water erosion on beds with small rills at moderate slopes and moderate rainfall intensities. The effects were mainly related to the fine grain layer, rills and slope of the original bed in the 2~(nd) round of tests. The findings can deepen our understanding of complex erosion resulted from a combination of wind and water actions and provide scientific references to regional soil and water conservation.     

作物残茬覆盖对农田土壤风蚀的影响

为定量评价干旱半干旱地区农田土壤抗风蚀效果,采用移动式风洞及其配套测试系统对内蒙古武川县上秃亥乡农田地表进行了原位测试研究。结果表明,不同风速下土壤风蚀量随作物残茬盖度的增加呈指数规律减少;40%以上残茬盖度可明显提高土壤颗粒起动风速并减少风蚀量;当风速为14~18 m/s时,地表作物残茬盖度为60%~80%具有较好的抗风蚀效果。     

沙地农业开发利用早期土壤风蚀的初步研究—以山东禹城为例

沙地农业开发利用，去除原有的植被，扰动了土体。在最初几年，土壤风蚀量不仅没有降低，而且明显增加。本文就产生土壤风蚀原因进行了分析，并对新开辟沙地的风蚀季相，以及高坑旱作型，灌溉型，流沙型，低温型土壤风蚀年际变化，进行了土壤风蚀量，风沙流结构的研究，对开发早期的不同类型的土壤风蚀，提出了不同的防治措施。     

土壤风蚀量随残茬高度的变化规律研究

在内蒙古自治区武川县建立农田土壤风蚀试验区,采用内蒙古农业大学研制的移动式风蚀风洞和旋风分离式集沙仪,直接在农田上观测不同残茬高度条件下的农田风蚀土壤损失情况。试验结果表明:土壤风蚀量和扬起沙尘的高度随风速的增加而增加,随着作物秸秆残茬高度的增加而降低,且输沙量与高度变化符合指数函数关系,土壤颗粒主要集中在近地表层内运动。保护性耕作可明显地提高启沙风速,减少农田土壤损失,当秸秆高度为30 cm时,风蚀量仅为传统耕地的1/4左右。     

An experimental study on the influences of water erosion on wind erosion in arid and semi-arid regions

Complex erosion by wind and water causes serious harm in arid and semi-arid regions. The interaction mechanisms between water erosion and wind erosion is the key to further our understanding of the complex erosion. Therefore, in-depth understandings of the influences of water erosion on wind erosion is needed. This research used a wind tunnel and two rainfall simulators to investigate the influences of water erosion on succeeding wind erosion. The wind erosion measurements before and after water erosion were run on semi-fixed aeolian sandy soil configured with three slopes(5°, 10° and 15°), six wind speeds(0, 9, 11, 13, 15 and 20 m/s), and five rainfall intensities(0, 30, 45, 60 and 75 mm/h). Results showed that water erosion generally restrained the succeeding wind erosion. At a same slope, the restraining effects decreased as rainfall intensity increased, which decreased from 70.63% to 50.20% with rainfall intensity increased from 30 to 75 mm/h. Rills shaped by water erosion could weaken the restraining effects at wind speed exceeding 15 m/s mainly by cutting through the fine grain layer, exposing the sand layer prone to wind erosion to airflow. In addition, the restraining effects varied greatly among different soil types. The restraining effects of rainfall on the succeeding wind erosion depend on the formation of a coarsening layer with a crust and a compact fine grain layer after rainfall. The findings can deepen the understanding of the complex erosion and provide scientific basis for regional soil and water conservation in arid and semi-arid regions.