检索结果-南通市图书馆

Journal of Integrative Agriculture 2016年第8期15卷 1863-1873页

作者： DENG Yu-song XIA Dong cai chong-fa DING Shu-wen College of Resources and Environment Huazhong Agricultural University Key Laboratory of Arable Land Conservation (Middle and Lower Reaches of Yangtze River) Ministry of Agriculture

the National Key Technologies R＆D Program of China during the 12th Five-Year Plan period （2011BAD31B00）

关键词： land use soil physic-chemical properties soil erodibility collapsing gully alluvial fan Anxi

Effects of soil shrinkage in permanent gullies formation: The case of Benggang erosion in the granite area of southern China

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Journal of Mountain Science 2021年第9期18卷 2328-2344页

作者： HUANG Wan-xia DENG Yu-song cai chong-fa JIANG Dai-hua Forestry College Guangxi UniversityNanning 530004China Resources and Environment College Huazhong Agricultural UniversityWuhan 430070China Agricultural College Guangxi UniversityNanning 530004China

Soil shrinkage is an important factor in slope destabilization in granitic areas, which is also one of the most important conditions for the formation of permanent gullies. This study explored the effect of soil shrinkage on permanent gullies, and Benggang erosion in granitic areas in southeastern China was used as an example. Three types of Benggang in granitic area were selected to examine the soil shrinkage of three soil layers(the lateritic, transitional and sandy layers) and their effect on the development of Benggang erosion was studied. The results show that the maximum values of COLEH and COLEV(coefficient of linear extensibility in horizontal and vertical directions, respectively) are 3.09% and 1.60% in the laterite layers, 2.71% and 2.13% in transition layers, and 1.10% and 1.82% in sandy layers, indicating that the shrinkage potential of the soil layers exhibits the following order, from highest to lowest: the laterite layer, transition layer, and sandy layer. With a decreasing volumetric water content, the linear shrinkage ratio increases gradually and eventually stabilizes, and in the laterite, transition and sandy layers, the average values of the maximum linear shrinkage are 1.50%, 2.09%, and 1.74%, respectively. Axial shrinkage is most obvious in the transition layers, in which the volume change in the form of subsidence is greater than that in other layers. The soil shrinkage curves fit the trilinear model(R2>0.9), and the soil shrinkage characteristic curves were divided into structural, basic, and residual sections. The correlation analysis shows that the soil shrinkage rate is positively correlated with clay and Fe2 O3 content and negatively correlated with sand content. Clay and sand contents are the most important factors influencing soil shrinkage. Soil oxides can influence soil shrinkage by affecting the particle composition of the soil, so soil shrinkage is closely related to soil clay minerals. Our findings can provide a theoretical basis f

关键词： Soil shrinkage Permanent gully Granite Benggang Soil layers

Effects of sediment load on the abrasion of soil aggregate and hydraulic parameters in experimental overland flow

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Journal of Integrative Agriculture 2020年第4期19卷 1117-1126页

作者： WANG Jun-guang YU Bing NI Shi-min GUO Zhong-lu cai chong-fa Key Laboratory of Arable Land Conservation(Middle and Lower Reaches of Yangtze River) Ministry of Agriculture and Rural Affairs/College of Resources and EnvironmentHuazhong Agricultural UniversityWuhan 430070.P.R.China Hubei Water Resources Research Institute Wuhan 430070.P.R.China

The breakdown of soil aggregates under rainfall and their abrasion in overland flow are important processes in water erosion due to the production of more fine and transportable particles and,the subsequent significant effect on the erosion ***,little is known about the effects of sediment load on the soil aggregate abrasion and the relationship of this abrasion with some related hydraulic ***,the potential effects of sediment load on soil aggregate abrasion and hydraulic parameters in overland flow were investigated through a series of experiments in a 3.8-m-long hydraulic flume at the slope gradients of 8.7 and 26.8%,unit flow discharges from 2×10^-3 to 6×10^-3 m^2 s^-1,and the sediment concentration from 0 to 110 kg *** the aggregates from Ultisols developed Quaternary red clay,Central *** results indicated that discharge had the most significant(Pfactor,and shear stress increased as a power function along with the increase of sediment concentration at different slope gradients and *** number was obviously affected by sediment concentration and it decreased as sediment concentration *** ratio of the residual weight to the initial weight of soil aggregates(Wr/Wi)was found to increase as the linear function with an increasing flow depth(P=0.008)or Reynolds number(P=0.002)in the sediment-laden *** Wr/Wi values followed a power function decrease with increasing friction factor or shear stress in the sediment-laden flow,indicating that friction factor is the best hydraulic parameter for prediction of soil aggregate abrasion under different sediment load conditio

关键词： soil aggregate sediment load hydraulic parameters overland flow

Vegetation Change Prediction with Geo-Information Techniques in the Three Gorges Area of China

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Pedosphere 2006年第4期16卷 457-467页

作者： M. T. JABBAR SHI Zhi-Hua WANG Tian-Wei cai chong-fa Huazhong Agriculture University Wuhan 430070 （China）. Department-of Soil and Water College of Agriculture University of Basrah （Iraq）

A computerized parametric methodology was applied to monitor, map, and estimate vegetation change in combination with '3S' (RS-remote sensing, GIS-geographic information systems, and GPS-global positioning system) technology and change detection techniques at a 1:50000 mapping scale in the Letianxi Watershed of western Hubei Province, China. Satellite images (Landsat TM 1997 and Landsat ETM 2002) and thematic maps were used to provide comprehensive views of surface conditions such as vegetation cover and land use change. With ER Mapper and ERDAS software, the normalized difference vegetation index (NDVI) was computed and then classified into six vegetation density classes. ARC/INFO and ArcView software were used along with field observation data by GPS for analysis. Results obtained using spatial analysis methods showed that NDVI was a valuable first cut indicator for vegetation and land use systems. A regression analysis revealed that NDVI explained 94.5% of the variations for vegetation cover in the largest vegetation area, indicating that the relationship between vegetation and NDVI was not a simple linear process. Vegetation cover increased in four of areas. This meant 60.9% of land area had very slight to slight vegetation change, while 39.1% had moderate to severe vegetation change. Thus, the study area, in general, was exposed to a high risk of vegetation cover change.

关键词： geo-information techniques vegetation change vegetation indices

Responses of Runoff and Soil Erosion to Vegetation Removal and Tillage on Steep Lands

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Pedosphere 2013年第4期23卷 532-541页

作者： XU Qing-Xue WANG Tian-Wei cai chong-fa LI Zhao-Xia SHI Zhi-Hua faNG Rong-Jie College of Environmental Science and Engineering Guilin University of Technology Key Lab of Subtropical Agriculture & Environment of Ministry of Agriculture Huazhong Agricultural University

Land use and land cover change is a key driver of environmental change. To investigate the runoff and erosion responses to frequent land use change on the steep lands in the Three Gorges area, China, a rainfall simulation experiment was conducted in plots randomly selected at a Sloping Land Conversion Program site with three soil surface conditions: existing vegetation cover, vegetation removal, and freshly hoed. Simulated rainfall was applied at intensities of 60 (low), 90 (medium), and 120 mm h 1 (high) in each plot. The results indicated that vegetation removal and hoeing significantly changed runoff generation. The proportion of subsurface runoff in the total runoff decreased from 30.3% to 6.2% after vegetation removal. In the hoed plots, the subsurface runoff comprised 29.1% of the total runoff under low-intensity rainfall simulation and the proportion rapidly decreased with increasing rainfall intensity. Vegetation removal and tillage also significantly increased soil erosion. The average soil erosion rates from the vegetation removal and hoed plots were 3.0 and 10.2 times larger than that in the existing vegetation cover plots, respectively. These identified that both the runoff generation mechanism and soil erosion changed as a consequence of altering land use on steep lands. Thus, conservation practices with maximum vegetation cover and minimum tillage should be used to reduce surface runoff and soil erosion on steep lands.

关键词： runoff generation sloping land subsurface runoff surface runoff vegetation cover

Effects of collapsing gully erosion on soil qualities of farm fields in the hilly granitic region of South China

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Journal of Integrative Agriculture 2016年第12期15卷 2873-2885页

作者： XIA Dong DING Shu-wen LONG Li DENG Yu-song WANG Qiu-xia WANG Shu-ling cai chong-fa College of Resources and Environment Huazhong Agricultural University Wuhan 430070 P.R. China Key Laboratory of Arable Land Conservation (Middle and Lower Reaches of Yangtze River) Ministry of Agriculture/Huazhong Agricultural University Wuhan 430070 P.R. China Sichuan Research Institute of Water Conservancy Science Chengdu 610072 P.R.China

Collapsing gully erosion is a specific form of soil erosion types in the hilly granitic region of tropical and subtropical South China, and can result in extremely rapid water and soil loss. Knowledge of the soil physical and chemical properties of farmland influenced by collapsing gully erosion is important in understanding the development of soil quality. This study was conducted at the Wuli Watershed of the Tongcheng County, south of Hubei Province, China. The aim is to investigate soil physical and chemical properties of three soil layers （0-20, 20-40 and 40-60 cm） for two farmland types （paddy field and upland field） in three regions influenced by collapsing gully erosion. The three regions are described as follows： strongly influenced region （SIR）, weakly influenced region （WIR） and non-influenced region （NIR）. The results show that collapsing gully erosion significantly increased the soil gravel and sand content in paddy and upland fields, especially the surface soil in the SIR and WIR. In the 0-20 cm layer of the paddy field, the highest gravel content （250.94 g kg-1） was in the SIR and the lowest （78.67 g kg-1） was in the NIR, but in the upland filed, the surface soil （0-20 cm） of the SIR and the 40-60 cm soil layer for the NIR had the highest （177.13 g kg-1） and the lowest （59.96 g kg-1） values of gravel content, respectively. The distribution of gravel and sand decreased with depth in the three influenced regions, but silt and clay showed the inverse change. In the paddy field, the average of sand content decreased from 58.6 （in the SIR） to 49.0% （in the NIR）, but the silt content was in a reverse order, increasing from 27.9 to 36.9%, and the average of the clay content of three regions showed no significant variation （P〈0.05）. But in the upland filed, the sand, silt and clay fluctuated in the NIR and the WIR. Soils in the paddy and upland field were highly acidic （pH〈5.2） in the SIR and WIR; moreover lower nutrient contents （soil organic matter （SOM）, to

关键词： collapsing gully erosion farmland hilly granitic region soil nutrient soil properties South China

Wetting Rate and Clay Content Effects on Interrill Erosion in Ultisols of Southeastern China

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Pedosphere 2010年第1期20卷 129-136页

作者： YAN Feng-Ling, SHI Zhi-Hua , cai chong-fa and LI Zhao-Xia Key Laboratory of Subtropical Agriculture & Environment, Ministry of Agriculture, Huazhong Agricultural University, Wuhan 430070 (China) Key Laboratory of Subtropical Agriculture & Environment Ministry of Agriculture Huazhong Agricultural University Wuhan 430070 (China)

An aggregate stability test and a simulated rainfall test were conducted on four representative Ultisols from southeastern China. The soils selected, with clay contents ranging between 117 and 580 g kg-1 , were derived from shale and Quaternary red clay. The stability of aggregates (2–5 mm in diameter) obtained from the soil samples were determined by the Le Bissonnais method. For determination of infiltration, runoff, and erosion, the soil samples were packed in 30 cm × 60 cm trays, wetted at rates of 2, 10, and 60 mm h-1 , and then exposed to simulated rainfall at 60 mm h-1 for 1 h. The results indicated that both aggregate stability and slaking caused by fast wetting increased with increasing clay content. The effect of wetting rate (WR) on infiltration and seal formation varied with clay contents. In the soil with low clay content (sandy loam), the infiltration rate was affected slightly by WR due to low aggregate stability and slaking. In the soils with medium clay content (silt clay loam and clay), WR affected infiltration significantly due to the high aggregate slaking force. In the soil with high clay content, the effect of WR on infiltration was significant, but not as evident as in the soils with medium clay content, which may be related to high aggregate stability by wetting partially compensating for slaking force. The effect of WR on soil loss was similar to that of runoff, but more pronounced. The findings from this study indicated that the relationship between wetting rate and clay content should be considered when predicting interrill erosion in Ultisols.

关键词： aggregate stability infiltration seal formation

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等高绿篱技术保水抗旱效益研究

长江流域资源与环境 2008年第5期17卷 793-797页

作者：程冬兵蔡崇法华中农业大学资源与环境学院湖北武汉430070

季节性干旱与水土流失并存是目前三峡库区面临的重要生态问题之一，严重影响了库区社会经济的可持续发展。等高绿篱技术是目前国内外广泛采用的一种十分有效的坡耕地植被恢复和水土保育技术，被认为是三峡库区农业生态系统持续发展的有... 详细信息

季节性干旱与水土流失并存是目前三峡库区面临的重要生态问题之一，严重影响了库区社会经济的可持续发展。等高绿篱技术是目前国内外广泛采用的一种十分有效的坡耕地植被恢复和水土保育技术，被认为是三峡库区农业生态系统持续发展的有效途径之一。选择新银合欢、黄荆和马桑3种绿篱，探讨其水土保育功效及抗旱效益。结果显示，等高绿篱具有显著的拦沙淤土效益，10年左右的时间，土坎高度增至近80cm，减缓坡度20。左右。与对照相比，栽种绿篱后，土壤有机质增加52％～65％，土壤容重减小14％～17％，尤其是非毛管孔隙增幅达135％～216％，等高绿篱模式下土壤保肥增肥效益显著，土壤结构改善明显。在旱季绿篱处理下地表土壤含水量高于对照达12．3％，蓄水保墒能力大大增强。按等高绿篱模式增加有效土层60cm计算，新银合欢、黄荆和马桑3个处理增加土壤水总库容分别为271、257和247mm，有力增强了土壤的抗旱性能。在绿篱—桔园系统下柑桔座果率比对照增加1．2％，其平均单产比对照高15％。

关键词：三峡库区等高绿篱保水抗旱

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砾石覆盖紫色土坡耕地水文过程

水科学进展 2012年第1期23卷 38-45页

作者：王小燕李朝霞蔡崇法华中农业大学农业部亚热带农业资源与环境重点实验室湖北武汉430070

紫色土中砾石分布广泛,地表常为砾石覆盖,砾石覆盖对土壤水文过程有着重要影响。试验小区(2 m×1 m)为坡度23°的坡耕地,试验降雨强度为(53.9±2.8)mm/h、(90.8±6.1)mm/h和(134.3±14.9)mm/h,砾石覆盖度为0%,11%,20%,33%和42%。通过原... 详细信息

紫色土中砾石分布广泛,地表常为砾石覆盖,砾石覆盖对土壤水文过程有着重要影响。试验小区(2 m×1 m)为坡度23°的坡耕地,试验降雨强度为(53.9±2.8)mm/h、(90.8±6.1)mm/h和(134.3±14.9)mm/h,砾石覆盖度为0%,11%,20%,33%和42%。通过原位人工模拟降雨试验,定量研究了不同降雨强度下砾石覆盖对降雨入渗、地表产流及壤中流产流的影响。结果表明:砾石覆盖对入渗过程影响显著,稳定入渗速率及稳定入渗系数与砾石覆盖度呈正相关关系,3种降雨强度下,稳定入渗系数分别为47.70%～86.59%,30.61%～82.83%、17.76%～77.44%,42%砾石覆盖度小区的稳定入渗速率分别是裸露小区的1.95～4.94倍;地表砾石覆盖延迟地表产流、减少地表径流量,地表产流时间随着砾石覆盖度的提高呈增加趋势,地表径流速率及地表径流系数随砾石覆盖度的增加而降低,相对地表径流系数与地表砾石覆盖度呈指数负相关关系;地表砾石覆盖促进壤中流的发生、增加壤中流量,壤中流产流时间随着砾石覆盖度的增加逐渐缩短,壤中流径流速率及壤中流径流系数随地表砾石覆盖度的增加而提高,相对壤中流径流系数与地表砾石覆盖度呈指数正相关关系。

关键词：砾石覆盖水文过程降雨入渗坡面径流壤中流产流时间紫色土模拟降雨

两种非饱和导水参数推求方法在紫色土上的应用

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水土保持学报 2007年第6期21卷 143-146,158页

作者：程冬兵蔡崇法华中农业大学资源与环境学院武汉430070

土壤非饱和导水参数的难于获取,限制了非饱和水流数值模拟技术的实际应用。本研究选择颇具代表性的土壤水分特征曲线推求法和简单入渗法两种方法,分别推求不同质地紫色土导水参数,并进行了分析比较。结果显示,土壤水分特征曲线推求法和... 详细信息

土壤非饱和导水参数的难于获取,限制了非饱和水流数值模拟技术的实际应用。本研究选择颇具代表性的土壤水分特征曲线推求法和简单入渗法两种方法,分别推求不同质地紫色土导水参数,并进行了分析比较。结果显示,土壤水分特征曲线推求法和简单入渗法,推求的非饱和导水率与计算值均具有较好的一致性。鉴于土壤水分特征曲线的易测优势和简单入渗法实验简便省时特点,采用这两种方法进行紫色土非饱和导水参数的推求或预报是可行的。

关键词：紫色土非饱和导水率水分特征曲线简单入渗法