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Soil erosion and management on the Loess Plateau

CAI Qiang-guo,

地理学报 , 2001,
Abstract: The Loess Plateau is well known to the world for its intense soil erosion. The root cause for river sedimentation of Yellow River (Huanghe) and its resultant "hanging river" in certain section is soil and water loss on the Loess Plateau. The Loess Plateau has a long cultivation history, hence population growth, vegetation degeneration and plugging constitute the chief reason for serious soil and water loss on Loess Plateau. This paper analyses several successful cases and failures in soil conservation, presents practical soil conservation technique and related benefit analysis, and discusses some effective methods adopted in China in soil erosion control, research directions and future perspectives on Loess Plateau.
Study of elemental distribution in soil on the loess plateau of China
Tian Junliang,Li Yaqi Liu PulingNorthwestern Institute of Soil,Water Conservation,Chinese Academy of Sciences,Shaanxi,China,
Tian Junliang
,Li Yaqi,Liu Puling

环境科学学报(英文版) , 1993,
Abstract: Instrument neutron activation analysis (INAA) has been employed in this study to determine 32 elements in soil on the loess plateau. The preliminary results suggest that geochemical characteristics of elements in the soil mainly retained those in the parent materials (loess). It has been found that fractional deposition among grain sizes in the process of loess transportation as well as the bioclimate in which the soil developed are main factors affecting the regional variations of elemental distribution in soil on the plateau. Contour maps of element concentrations plotted from the trend analyses exhibit the major patterns of the distributions and variations on the plateau. Furthermore, the study also provides evidence for the aeolian theory of the loess transportation in China.
Study on Integrated Benefit of Rainwater Resources Utilization in Small Watershed on the Loess Plateau
黄土高原小流域雨水资源化综合效益评价体系研究

ZHAO Xi-ning,FENG Hao,Wu Pute,WANG Wan-zhong,
赵西宁
,冯浩,吴普特,王万忠

自然资源学报 , 2005,
Abstract: Rainwater resources utilization is an effective measure for solving wa ter resources shortage and eco,environmental rehabilitation in Loess Plateau of China.Research of rainwater resources integrated benefit evaluation is a core pr oblem concerning development of dryland agriculture,soil and water environmental protection as well as coordinated economic and eco,environmental development.No wadays the evaluation models and indicators system of rainwater resources mostly use economic benefit maximum as optimized objection function,regardless of soci al benefit and eco,environmental benefit.Especially research of rainwater resour ces integrated benefit in Loess Plateau is inadequate.Based on the current situa tion of rainwater resources utilization and the characteristic of converting rai nwater into rainwater resources,applying analytic hierarchical process theory,th is paper establishes the mathematical model and indicators system for integrated benefit evaluation of rainwater resources utilization by taking small watershed as a research unit and rainwater resources as a research object.The evaluation indicators system is proposed based on characteristics and principles of scienti fic,practical and concise.The indicators system includes three aspects such as e conomic benefit,social benefit and eco,environmental benefit and systematically reflects rainwater resources utilization features in small watershed.Because of the complex relation of indicators factors,synthetically benefit evaluation incl udes quantitative and qualitative aspects.The evaluating model and the indicator s system are applied to evaluate synthetically the status of rainwater resources utilization in Nihegou watershed in Shaanxi Province.The evaluation model playe d an important role in the evaluation and management of rainwater resources sust ainable utilization and eco,environment construction on the Loess Plateau.
Soil moisture and evapotranspiration of different land cover types in the Loess Plateau, China
S. Wang, B. J. Fu, G. Y. Gao, X. L. Yao,J. Zhou
Hydrology and Earth System Sciences (HESS) & Discussions (HESSD) , 2012,
Abstract: We studied the impacts of re-vegetation on soil moisture dynamics and evapotranspiration (ET) of five land cover types in the Loess Plateau in northern China. Soil moisture and temperature variations under grass (Andropogon), subshrub (Artemisia scoparia), shrub (Spiraea pubescens), plantation forest (Robinia pseudoacacia), and crop (Zea mays) vegetation were continuously monitored during the growing season of 2011. There were more than 10 soil moisture pulses during the period of data collection. Surface soil moisture of all of the land cover types showed an increasing trend in the rainy season. Soil moisture under the corn crop was consistently higher than the other surfaces. Grass and subshrubs showed an intermediate moisture level. Grass had slightly higher readings than those of subshrub most of the time. Shrubs and plantation forests were characterized by lower soil moisture readings, with the shrub levels consistently being slightly higher than those of the forests. Despite the greater post-rainfall loss of moisture under subshrub and grass vegetation than forests and shrubs, subshrub and grass sites exhibit a higher soil moisture content due to their greater soil retention capacity in the dry period. The daily ET trends of the forests and shrub sites were similar and were more stable than those of the other types. Soils under subshrubs acquired and retained soil moisture resources more efficiently than the other cover types, with a competitive advantage in the long term, representing an adaptive vegetation type in the study watershed. The interactions between vegetation and soil moisture dynamics contribute to structure and function of the ecosystems studied.
A study on water restoration of dry soil layers in the semi-arid area of Loess Plateau
黄土高原半干旱区土壤干层水分恢复研究

WANG Zhiqiang,LIU Baoyuan,LU Bingjun,
王志强
,刘宝元,路炳军

生态学报 , 2003,
Abstract: A dry soil layer is defined as any layer within the soil profile that maintains a persistent low water content, which generally results from negative evapo transpiration equilibrium. Nearly all soils under perennial leguminous crops and re vegetated forests on Loess Plateau contain dry soil layers, which constitutes a serious obstacle to the sustainable land use of Loess Plateau of China. The formation, properties and distribution of dry soil layers in the Loess Plateau has been extensively studied, but ...
ON SOIL RESOURCES AND THE WAY FOR ITS AMELIORATION AND UTILIZATION IN ZHUANYAOGOU EXPERIMENT AREA OF THE LOESS PLATEAU
黄土高原砖窑沟试验区土壤资源与改良利用途径

Duan Jiannan,WangGailan,Li Shuanhuai,Zhang Jinfeng,
段建南
,王改兰

自然资源学报 , 1994,
Abstract: The features of soil resources and the measures and effects of soil amelioration and utilization were studied systematically by means of field experiments, location observations and field surveys on the comprehensive harnessing experiment area of Zhuanyaogou basin in Hequ county, loess hilly region in northwestern Shanxi. The results show that the area is abundant in soil resources, but poor in soil fertility. Reasons for this are mainly sandy texture, low content of organic matter, many climatic disasters, severe soil erosion and poor economy. The soil fertility and its environment condition have been improved efficiently by series of measures, which consist of building bench terrace and practicing technique of improving fertility quickly on new terraced fields, carrying out optimum application plans with storing water, using water rationally, raising water-use efficiency and so on. Meanwhile, the way that is of universal significance in the region for improving soil fertility was developed based on the experiments and practice.
Watershed discretization based on multiple factors and its application in the Chinese Loess Plateau
Y. D. Xu, B. J. Fu, C. S. He,G. Y. Gao
Hydrology and Earth System Sciences (HESS) & Discussions (HESSD) , 2012,
Abstract: The spatial discretization of watersheds is an indispensable procedure for representing landscape variations in eco-hydrological research, representing the contrast between reality and data-supported models. When discretizing a watershed, it is important to construct a scheme of a moderate number of discretized factors while adequately considering the actual eco-hydrological processes, especially in regions with unique eco-hydrological features and intense human activities. Because of their special lithological and pedologic characteristics and widespread man-made vegetation, discretization of watersheds in the Loess Plateau in Northern China is a challenge. In order to simulate the rainfall-runoff process, a watershed in the Loess Plateau, referred as Ansai, was spatially discretized into new units called land type units. These land type units were delineated under a scheme of factors including land use, vegetation condition, soil type and slope. Instead of using units delineated by overlaying land use and soil maps, the land type units were used in the Soil and Water Assessment Tool (SWAT). Curve numbers were assigned and adjusted to simulate runoff, using the US Natural Resources Conservation Service (NRCS) curve number method. The results of the runoff simulation better matched actual observations. Compared to the results that used the original units, the coefficient of determination (R2) and the Nash-Sutcliffe coefficient (ENS) for monthly flow simulation increased from 0.655–0.713 and 0.271–0.550 to 0.733–0.745 and 0.649–0.703, respectively. This method of delineating into land type units is an easy operation and suitable approach for eco-hydrological studies in the Chinese Loess Plateau and other similar regions. It can be further applied in soil erosion simulation and the eco-hydrological assessment of re-vegetation.
Watershed discretization based on multiple factors and its application in the Chinese Loess Plateau
Y. Xu,B. Fu,C. He,G. Gao
Hydrology and Earth System Sciences Discussions , 2011, DOI: 10.5194/hessd-8-9063-2011
Abstract: The spatial discretization of watersheds is an indispensable procedure for representing landscape variations in eco-hydrological research, representing the contrast between reality and data-supported models. When discretizing a watershed, it is important to construct a scheme of a moderate number of discretized factors while adequately considering the actual eco-hydrological processes, especially in regions with unique eco-hydrological features and intense human activities. Because of their special lithological and pedologic characteristics and widespread man-made vegetation, discretization of watersheds in the Loess Plateau in Northern China is a challenge. In order to simulate the rainfall-runoff process, a watershed in the Loess Plateau, referred as Ansai, was spatially discretized into new units called land type units. These land type units were delineated under a scheme of factors including land use, vegetation condition, soil type and slope. Instead of using units delineated by overlaying land use and soil maps, the land type units were used in the Soil and Water Assessment Tool (SWAT). Curve numbers were assigned and adjusted to simulate runoff, using the US Natural Resources Conservation Service (NRCS) curve number method. The results of the runoff simulation better matched actual observations. Compared to the results that used the original units, the coefficient of determination (R2) and the Nash–Sutcliffe coefficient (ENS) for monthly flow simulation increased from 0.710–0.721 and 0.581–0.656 to 0.726–0.731 and 0.692–0.703, respectively. This method of delineating into land type units is an easy operation and suitable approach for eco-hydrological studies in the Chinese Loess Plateau and other similar regions. It can be further applied in soil erosion simulation and the eco-hydrological assessment of re-vegetation.
Evaluation of soil erodibility on the Loess Plateau
黄土高原地区土壤可蚀性及其应用研究

ZHANG Ke-Li,
张科利

生态学报 , 2001,
Abstract: Soil erosion is now universally reckoned as an ecological environment problem,which results in land degradation and a band of ecological problems such as water pollution and flood disaster,Especially in the vast northwest region of China,a key to restore ecological environment is to control soil erosion.Besides vegetation disruption,rainfall concentration,and steep farmland ect,the susceptibilities of loess to erosion substantially conduce to severe soil erosion on the loess plateau.Soil erodibility being a...
A policy and technical measures for controlling soil and water loss in the Loess Plateau of China
Wu Qinxiao,Li Yinchu,
Wu Qinxiao
,Li Yinchu

环境科学学报(英文版) , 1990,
Abstract: Loess Plateau is the most serious region of soil and water loss in China and the world. The sediment carried into the Yellow River amounts to 1.6 billion tons every year. This paper reviews the factors and reasons for erosion in this area, and puts forward a comprehensive controlling policy on the basis of the principles of ecology and practise of Chinese scientists for 40 years. In conformity with the policy, a number of technical measures for controlling soil and water loss are suggested.
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