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Soil and water erosion in its relation to slope field productivity in hilly gully areas of the Loess Plateau


生态学报 , 2003,
Abstract: Soil and water erosion is probably the most serious ecological environment problem in the Loess Plateau, especially on the slope fields of this semi-arid hilly gully region. It results in decline of top soil thickness, soil nutrients loss, water pollution, flood disaster and land productivity degradation. But the relationship between soil and water erosion and land productivity is not well defined yet. Without an adequate definition, the selection of proper management strategies to optimize perennial crop a...
The impacts of urbanization on soil erosion in the Loess Plateau region

SUN Hu,GAN Zhi-mao,YAN Jun-ping,

地理学报 , 2001,
Abstract: The accelerated urbanization has resulted in new soil erosion in the Loess Plateau region since the 1980s. A concept of urban erosion and its impacts on environment are discussed. The experimental studies and field investigations show that those loose silt and earth piles formed by urban construction can be eroded seriously: Under stormy rain, the amount of sediment from steep man-dumped slope is 10.8-12.2 times that of from uncovered slope land; the result of experiments with the wind tunnel also shows that the damage to the surface structure of dry loess can cause serious soil erosion by wind in some cities of the region. Even if in the urban built-up area, there are many loose sandy soil, mud and silt, which are washed into rivers by city’s ground flow in the rainy season. So, anthropogenically induced soil erosion has made soil erosion more serious around the urban areas. And the urban eroded environment has several characteristics such as fragility, complexity, seasonality and quick variability. Urban areas witness a quick economic growth and have more construction projects than rural areas, which brings more intensive changes of environments during a short period of time or adds some new elements to the erosion system. Therefore erosion has experienced more intensive impact by human activities. So, the possible impact of urbanization on erosion environment must be taken into consideration when designing or planning to exploit natural resources or to develop urban areas in the Loess Plateau.

第四纪研究 , 1993,
Abstract: Soil erosion is a main environmental problem in Loess Plateau of China. The genesis of soil erosion has its own natural features. Three major erosion types might be summarized as follows: (1) Water Flow Erosion, (2) Gravitational Erosion, (3) Wind-force Erosion. The dominant natural factors of erosion are: (1) Precipitation, (2) Landform, (3) Vegetation, (4) The characttristics of soil. Precipitation and landform were called "erodibility". Vegetation and the characteristics of soil were called "stability". Whether the erosion will occur and its intensity depend on the interact result between erodibility and stability. Erosion will occur if the effect of erodibility factors is greater than the effect from stability factors, otherwise no erosion will occur.
Effects of land-use pattern change on soil and water loss at the catchment scale in the hilly and gully area of the loess plateau of China

ZHAO Wen-Wu,

生态学报 , 2004,
Abstract: The hilly and gully area of the Loess Plateau of China suffers some of the highest soil erosion rates on the Earth, and one of the most important reasons is irrational land-use. The study on the effects of land-use pattern on soil and water loss is helpful not only to the comprehensive watershed management but also to further understanding of landscape pattern and ecological process. A case study was carried out in Xinghe catchment of the Loess Plateau, and DEM, land use maps, rainfall and hydrological dat...
Effects of Stubble Management on Soil Fertility and Crop Yield of Rainfed Area in Western Loess Plateau, China  [PDF]
G. B. Huang,Z. Z. Luo,L. L. Li,R. Z. Zhang,G. D. Li,L. Q. Cai,J. H. Xie
Applied and Environmental Soil Science , 2012, DOI: 10.1155/2012/256312
Abstract: The combination of continuous cereal cropping, tillage and stubble removal reduces soil fertility and increases soil erosion on sloping land. The objective of the present study was to assessment soil fertility changes under stubble removal and stubble retention in the Loess Plateau where soil is prone to severe erosion. It was indicated that soil N increased a lot for and two stubble retention treatments had the higher N balance at the end of two rotations. Soil K balance performed that soil K was in deficient for all treatments and two stubble retention treatments had lower deficit K. The treatments with stubble retention produced higher grain yields than the stubble removal treatments. It was concluded that stubble retention should be conducted to increase crops productivity, improve soil fertility as well as agriculture sustainability in the Loess plateau, China. 1. Introduction Crop stubble is a main agricultural waste material as well as a renewable resource, due to being rich in nitrogen (N), phosphorus (P), and potassium (K). China has a long tradition of efficient recycling of organic residues in agriculture, but this tradition is rapidly disappearing following the intensification of agricultural production, the increased use of mineral fertilizers, and the increasing urbanization and decoupling of crop production and animal production [1]. The intensification of agricultural production has greatly increased the agricultural production, but at the same time, it has contributed to a decrease in resource use efficiency, land degradation through increased wind and water erosion, and pollution of ground water and surface waters [2–4]. There are approximately 0.7 billion ton of organic residues produced each year in China, which contain 3, 0.70, and 7 million ton of N, P, and K, respectively, equivalent to 25% of the total chemical fertilizers used for farming system [5]. In the last few decades, there has been increased interest in the reuse of crop stubble for soil ecology [6, 7], crop system [8, 9], and atmospheric environment [10] worldwide. Retention of plant residues has been found to have many long-term benefits around the world. These crop stubble constitutes a mulch cover that protects the soil against run-off and erosion [11] and increases the percentage of organic matter in the surface soil layer [12, 13]. Nutrient loss due to runoff is also decreased [14]. The capacity of the soil surface to intercept rainfall is improved because of changes in soil roughness, soil surface porosity, and hydraulic conductivity of the topsoil. Mulching also
Review of Soil Erosion Research Methods in the Chinese Loess Plateau

李东, 魏霞, 李耀军
Open Journal of Soil and Water Conservation (OJSWC) , 2013, DOI: 10.12677/ojswc.2013.11006
Abstract: 土壤侵蚀是复杂的综合性环境问题,在我国黄土高原地区尤为突出,针对此类问题将黄土高原地区对土壤侵蚀的研究分为实验法和模型法两大类,并对包括遥感监测、降雨模拟、示踪技术和水文模型在内的研究方法进行了综述与归纳,分析探讨了各种研究方法的特点、局限性、使用情况及发展方向,为研究黄土高原地区土壤侵蚀规律及其机理研究提供了相关参考。
 Soil erosion is a complex and comprehensive environmental problem, especially in the area of the Loess Plateau, China. The research methods of the soil erosion are divided into experimental and model methods in the Loess Plateau area. The existing research methods of soil erosion, including remote sensing monitoring, rainfall simulation experiments, tracer technique and hydrological models, are reviewed and summarized. The characteristics, limitations, application and development direction of various research methods are analyzed and discussed to provide relevant references for the further study on soil erosion in the Loess Plateau.
Assessment indicators of soil quality in hilly Loess Plateau

XU Mingxiang,LIU Guobin,ZHAO Yunge,

应用生态学报 , 2005,
Abstract: By the methods of sensitivity analysis,main component analysis and discriminant analysis,this paper screened the sensitive indicators from 32 soil attributes to assess the productivity and erosion-resistance ability of the soils in hilly Loess Plateau.The results showed that soil available phosphorus content,anti-scouring ability,infiltration coefficient,labile organic carbon content,organic matter content and urease activity were the most sensitive indicators for soil quality assessment and the main targets for soil quality management and improvement,while soil biological indicators were with high and medium sensitivity.Five soil quality factors were summed up from 29 soil chemical,physical and biological attributes,i.e.,organic matter,texture,phosphorus,porosity and microstructure.Except the factor porosity,the other four factors were significantly different between different land use types.Eight indicators including soil organic matter content,infiltration coefficient,anti-scouring ability,CEC,invertase activity,mean weight diameter (MWD) of aggregates,available phosphorus,and MWD of micro-aggregate were identified as the assessment indicators of the soil quality in hilly Loess Plateau,with the organic matter content,infiltration coefficient and anti-scouring ability as the key indicators.
Effects of erosion and deposition on particle size distribution of deposited farmland soils on the chinese loess plateau
Zhao, Pei;Shao, Ming An;Omran, Wail;Amer, Abdel-monem Mohamed;
Revista Brasileira de Ciência do Solo , 2011, DOI: 10.1590/S0100-06832011000600028
Abstract: particle size distribution (psd) in the soil profile is strongly related to erosion, deposition, and physical and chemical processes. water cycling and plant growth are also affected by psd. material sedimented upstream of the dam constructions formed large areas of deposited farmland (df) soils on the chinese loess plateau (clp), which has been the site of the most severe soil erosion in the world. two dfs without tillage on the clp were chosen to study the combined effect of erosion and check dams on psd. eighty-eight layers (each 10 cm thick) of filled deposited farmland (fdf) soils and 22 layers of silting deposited farmland (sdf) soils of each studied soil profile were collected and 932 soil samples were investigated using laser granulometry. the particle sizes were stratified in both dfs based on soil properties and erosion resistance. the obtained results of clay and silt fractions showed similar horizontal distribution, indicating parallel characteristics of erosion and deposition processes. fine sand represented the largest fraction, suggesting the preferential detachment of this fraction. the most erodible range of particle sizes was 0.25-0.5 mm, followed by 0.2-0.25 mm in the studied soil profiles. the correlation between particle size and soil water contents tended to increase with increasing water contents in fdf. due to the abundant shallow groundwater, the relationship between particle size and soil water content in sdf was lost. further studies on psd in the df area are needed to enhance the conservation management of soil and water resources in this region.
The distribution of soil organic carbon as affected by landforms in a small watershed of gully region of the Loess Plateau

LI Linhai,GAO Erhu,MENG Meng,WEI Xiaorong,

生态学报 , 2013,
Abstract: Soil organic carbon plays important role in soil quality changes and terrestrial carbon cycling. However, the relationships between soil organic carbon distribution and landscape positions were not well understood, which are essential for the precisely predication of the spatial distribution of soil organic carbon and for the rational management of soil organic carbon, as well as for the assessment of the dynamics of soil organic carbon at different landscape positions at different landscape scales. China's Loess Plateau is a major region for agricultural production, and an ecological ecotone in northwest China, which suffers serious land degradation and ecologically economic problems due to the soil erosion in the region. The distribution and cycling of soil organic carbon were related not only with the maintaining and improving of soil quality in the region, but also with the response and adaptation of soil ecosystems to the future global climate change, and thus should be carefully assessed. In this study, we investigated the distribution of soil organic carbon and labile organic carbon at various landforms, that is, plateau land, sloping land, gully bottom and terrace land. We also anlyzed the differences of carbon management index at various landscape positions. The objectives were to establish the relationships between soil organic carbon and the landscape positions in a gully watershed of the Loess Plateau, and to understand how the labile organic carbon and carbon pool management index respond to the landscape positions. The results showed that soil organic carbon and labile organic carbon in the small watershed of the Loess Plateau have variance coefficients ranging from 32% to 70%, indicating medium to high variation. The highest and lowest of total and labile organic carbon were observed in plateau land and gully bottom, respectively. Additionally, total and labile organic carbon decreased with soil depth and the most decrease was tested in high labile organic carbon fraction. The carbon management index in this study can sensitively indicate the response of soil organic carbon to landforms. Among the 3 labile organic carbon fractions, the middle labile organic carbon based carbon management index present the best indication for carbon along soil profile. Our results indicate that the effects of landform on soil organic carbon can partly explain the regional distribution of soil organic carbon in the Loess Plateau.

Liu Liming,

自然资源学报 , 1992,
Abstract: On the basis of a survey of soil erosion and land use with remote sensing, severe accelerated erosion is considered to be the primary cause of poor agricultural ecnomical condition in the hill and gully region of the Loess Plateau. It is a result of intensive cultivation and unreasonable land use. Both of these two have a long history. This paper tries to introduce a methodology of quantitative analysis of soil erosion with remote sensing information. Small watershed is taken as the study unit of the erosion system. Thus, two mathematical erosion models which predict the sheet erosion, the rill erosion and the sediment yield of small watershed are developed, according to systematical experimental data and field survey results as well as remote sensing data. Finally, the principles of Soil Erosion Information System (SEIS) are discussed. They are used for dynamically monitoring soil erosion, land use planning and soil conservation.
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