Driving forces and their interactions of soil erosion in soil and water conservation regionalization at the county scale with a high cultivation rate

Soil erosion control based on county scale Soil and Water Conservation Regionalization(SWCR)is an essential component of China's ecological civilization construction.In SWCR,the quantitative analysis of the spatial heterogeneity and driving factors of soil erosion among different regions is still lacking.It is of great significance for soil erosion control to deeply examine the factors contributing to soil erosion(natural,land use,and socioeconomic factors)and their interaction at the county and regional levels.This study focused on a highly cultivated area,Hechuan District of Chongqing in the Sichuan Basin.The district(with 30 townships)was divided into four soil and water conservation regions(Ⅰ-Ⅳ)using principal component and hierarchical cluster analysis.The driving factors of soil erosion were identified using the geographical detector model.The results showed thatⅰ)the high cultivation rate was a prominent factor of soil erosion,and the sloping farmland accounted for 78.4%of the soil erosion in the study area;ⅱ)land use factors demonstrated the highest explanatory power in soil erosion,and the average interaction of land use factors explained 60.1%of soil erosion in the study area;ⅲ)the interaction between natural factors,socioeconomic factors,and land use factors greatly contributes to regional soil erosion through nonlinear-enhancement of double-factor enhancement.This study highlights the importance of giving special attention to the effects of land use factors on soil erosion at the county scale,particularly in mountainous and hilly areas with extensive sloping farmland and a high cultivation rate.

Results and Application of Soil and Water Conservation Monitoring in the Yellow River Basin

Since water and soil conservation monitoring in the Yellow River Basin entered a new stage at the end of the 20th century,the monitoring scope has been expanding,the monitoring accuracy has been improving,the monitoring content and indicators have been increasing,and the monitoring technology and methods have been improving.This paper mainly analyzes the status of soil and water conservation monitoring in the Yellow River Basin,as well as the construction of the monitoring system and related research,in order to provide a reference for watershed management and development and the scientific research of water and soil conservation.

Integrating water use systems and soil and water conservation measures into a hydrological model of an Iranian Wadi system

Water resources are precious in arid and semi-arid areas such as the Wadis of Iran. To sustainably manage these limited water resources, the residents of the Iranian Wadis have been traditionally using several water use systems(WUSs) which affect natural hydrological processes. In this study, WUSs and soil and water conservation measures(SWCMs) were integrated in a hydrological model of the Halilrood Basin in Iran. The Soil and Water Assessment Tool(SWAT) model was used to simulate the hydrological processes between 1993 and 2009 at daily time scale. To assess the importance of WUSs and SWCMs, we compared a model setup without WUSs and SWCMs(Default model) with a model setup with WUSs and SWCMs(WUS-SWCM model). When compared to the observed daily stream flow, the number of acceptable calibration runs as defined by the performance thresholds(Nash-Sutcliffe efficiency(NSE)≥0.68, –25%≤percent bias(PBIAS)≤25% and ratio of standard deviation(RSR)≤0.56) is 177 for the Default model and 1945 for the WUS-SWCM model. Also, the average Kling–Gupta efficiency(KGE) of acceptable calibration runs for the WUS-SWCM model is higher in both calibration and validation periods. When WUSs and SWCMs are implemented, surface runoff(between 30% and 99%) and water yield(between 0 and 18%) decreased in all sub-basins. Moreover, SWCMs lead to a higher contribution of groundwater flow to the channel and compensate for the extracted water by WUSs from the shallow aquifer. In summary, implementing WUSs and SWCMs in the SWAT model enhances model plausibility significantly.

Benefit measurement of the soil and water conservation for ecological forestry engineering

Data were collected from Three-north Region, Middle and upper reaches region of Yangtze River and Coastal region. By analysis of factors influencing soil erosion, the longitude, latitude, annual precipitation, and the slope degree were selected as regional independent variables and canopy density and stock litter were selected as independent variables, and integral diffusing models were established for evaluation of the benefit of soil and water conservation of forest. By solving the parameters of models using the package of STATISTICA, the Power function between independent variables and dependent variables was set up. The soil conservation amount of forest and economic values were estimated using the contrast method for the ecological forestry engineering of the above three areas.

Effects of Different Tillage Systems on Soil Properties,Root Growth,Grain Yield,and Water Use Efficiency of Winter Wheat (Triticum aestivum L.) in Arid Northwest China

Studies on root development, soil physical properties, grain yield, and water-use efficiency are important for identifying suitable soil management practices for sustainable crop production. A field experiment was conducted from 2006 through 2008 in arid northwestern China to determine the effects of four tillage systems on soil properties, root development, water-use efficiency, and grain yield of winter wheat （Triticum aestivum L.）. The cultivar Fan 13 was grown under four tillage systems：conventional tillage （CT） without wheat stubble, no-tillage without wheat stubble mulching （NT）, no-tillage with wheat stubble standing （NTSS）, and no-tillage with wheat stubble mulching （NTS）. The soil bulk density （BD） under CT system increased gradually from sowing to harvest, but that in NT, NTSS, and NTS systems had little change. Compared to the CT system, the NTSS and NTS systems improved total soil water storage （0-150 cm） by 6.1-9.6 and 10.5- 15.3% before sowing, and by 2.2-8.9 and 13.0-15.1% after harvest, respectively. The NTSS and NTS systems also increased mean dry root weight density （DRWD） as compared to CT system. The NTS system significantly improved water-use efficiency by 17.2-17.5% and crop yield by 15.6-16.8%, and the NTSS system improved that by 7.8-9.6 and 7.0-12.8%, respectively, compared with the CT system. Our results suggested that Chinese farmers should consider adopting conservation tillage practices in arid northwestern China because of benefits to soil bulk density, water storage, root system, and winter wheat yield.

Benefits of Conservation Agriculture on Soil and Water Conservation and Its Progress in China

Conservation agriculture has been practised for three decades and has been spread widely. There are many nomenclatures surrounding conservation agriculture and differ to each other lightly. Conservation agriculture （CA） is a system approach to soil and water conservation, high crop productivity and profitability, in one word, it is a system approach to sustainable agriculture. Yet, because conservation agriculture is a knowledge-intensive and a complex system to learn and implement, and also because of traditions of intensive cultivation, adoption rates have been low, since to date, only about seven percent of the world＇s arable and permanent cropland area is farmed under conservation agriculture. The practice and wider extention of conservation agriculture thus requires a deeper understanding of its ecological underpinnings in order to manage its various elements for sustainable intensification, where the aim is to conserve soil and water and improve sustainability over the long term. This paper described terms related to conservation agriculture, presented the effects of conservation agriculture on soil and water conservation, crop productivity, progress and adoption of CA worldwide, emphasized obstacles and possible ways to increase CA adoption to accelerate sustainable development of China agriculture.

Water and Soil Conservation in Taiwan Based on Theoretical Research of Water and Soil Ecology

Taiwan has always attached great importance to management of mountain slopes, and its steepslope water and soil conservation system has been a reference for the water and soil conservation in hot and rainy regions. From the perspective of water and soil ecology theory, new forms of water and soil loss emerged since the industrialization and urbanization of Taiwan, also known as hidden water and soil loss, such as soil hardening, change of original landform, destruction of ecological landscape etc.. These losses should be controlled through water and soil conservation measures such as initial involvement, dynamic analysis, systematic treatment and disaster avoidance, all production and construction activities should follow three elements(water, soil and vegetation) and their correlation laws, in order to maintain water and soil ecological balance. By integrating water and soil ecological concepts, water and soil conservation in Taiwan will make more progress.

Study on Water and Soil Conservation Effects of Grassland Based on Live Vegetation Volume at Various Time Scales

Based on the observation data of rainfall,vegetation,runoff and sediment yield in the experimental plots located in Hetian Town,Changting County of Fujian Province during 2007-2010,the changing characteristics and interrelation of live vegetation volume of grass,rainfall parameters,and water(soil)conservation effect RE(SE)were analyzed at four time scales of rainfall event,month,season,and year.The results showed that with the increase of time scales,the rainfall and vegetation indicators increased or decreased more or less,and the variation range of RE was small,while SEslowly decreased.The mean REchanged by 10%-20% at different time scales,and the observed water conservation effect of the grassland was the best at season scale while the worst at year scale.The soil conservation effect of the grassland was the best at month scale and the worst at season scale.The water conservation effect of the grass was mainly controlled by rainfall factors,including rainfall duration and precipitation at rainfall event scale,and the maximum intensity of precipitation within 30 min at longer time scales.However,the soil conservation effect of the grass was mainly controlled by vegetation factors,including the contribution of the litter on soil surface at rainfall event scale,the interaction of rainfall and vegetation at month and season scales,and the live vegetation volume of the grass at year scale.Consequently,at different time scales,the factors influencing water and soil conservation changed and interacted,and the observed water and soil conservation effects were also different,indicating that the influence of time scales deserves attention in both research and management practices.

Regions and Their Typical Paradigms for Soil and Water Conservation in China

China is experiencing conflicts between its large population and scarce arable land,and between a demand for high productivity and the severe soil erosion of arable land.Since 1949,China has committed to soil and water conservation(SWC),for which eight regions and 41 subregions have been developed to improve the environment and increase land productivity.To obtain information from the regional planning and strategies for SWC and to explore whether SWC practices simultaneously contribute to soil conservation,ecosystem functioning,and the livelihoods of local farmers,and to summarize the successful experiences of various SWC paradigms with distinct characteristics and mechanisms of soil erosion,this paper systematically presents seven SWC regions(excluding the Tibetan Plateau region)and 14 typical SWC paradigms,focusing on erosion mechanisms and the key challenges or issues in the seven regions as well as on the core problems,main objectives,key technologies,and the performance of the 14 typical paradigms.In summary,the 14 typical SWC paradigms successfully prevent and control local soil erosion,and have largely enhanced,or at least do not harm,the livelihoods of local farmers.However,there remain many challenges and issues on SWC and socioeconomic development that need to be addressed in the seven SWC regions.China,thus,still has a long way to go in successfully gaining the win-win objective of SWC and human aspects of development.

Relationship Between Soil and Water Conservation Practices and Soil Conditions in Low Mountain and Hilly Region of Northeast China

The soil and water conservation practices of ecological restoration(ER),fish scale pit(FP),furrow and ridge tillage across the slope(FR),shrub strips(SS),and vegetation-covered ridge(VR)are characteristic of the Jixing small watershed of the low mountain and hilly region of Jilin Province,Northeast China.This study aims to elucidate the effects of soil and water conservation practices on soil conditions after the short-term implementation of practices.Soil samples were collected from five soil and water conservation sites(ER,FP,FR,SS,and VR)and two controls(BL and CT)to investigate their properties.To evaluate the influence of soil and water conservation practices on soil quality,an integrated quantitative index,soil quality index(QI),was developed to compare the soil quality under the different soil and water conservation practices.The results show that not all soil and water conservation practices can improve the soil conditions and not all soil properties,especially soil organic carbon(SOC),can be recovered under soil and water conservation practice in short-term.Moreover,the QI in the five soil and water conservation practices and two controls was in the following order:ER>VR>BL>FR>CT>SS>FP.ER exhibited a higher soil quality value on a slope scale.In the low mountain and hilly region of Northeast China,ER is a better choice than the conversion of farmlands to planted grasslands and woodlands early in the soil and water conservation program.

Analysis of Coupling between Soil and Water Conservation and Economic-social Development

The coupling relation exists in water and soil conser-vation and economic-social development. The article analyses the relation of soil and water conservation and economic-social development stages as well as the coupling analytical method. Then calculates the expecting income by dispersing Markov decision and calculates the correlation coefficient and the re-lationship degree. The article obtains the relationship of soil and water conservation investments and all kinds of incomes. Finally, it analyzes the important meaning in socio-economic development of water and soil conservation.

Soil water characteristics in mountain poplar stand and its benefits to soil and water conservation in loess hilly region

The soil physical properties,its water characteristics and the benefits to soil and water conservation in mountain poplar stand were determined and studied. The results of the study show that the compaction in soil profile is relatively homogeneous.the specific gravity and volume weight of soil increase with deepening of soil horizon. The water infiltration rate of soil in the stand is 17,6 times as high as in rangeland.Owing to the intense absorption of water by root system of plants,a drying layer is formed in soil horizon from 2.3 m to 2.7m,showing that the subsoil moisture is in the state of deficit. The annual water storage capacity in 2 m of soil horizon is 360 mm 370mm,or 63% 65% of annual precipitation. Compared with farmland,mountain poplar stand reduces the surface runoff and soil loss by 70% and 99%,respectively,indicating the great benefits to soil and water conservation.

The Brief Introduction to the Sino-US Joint Centers for Soil and Water Conservation and Environmental Protection

Erosion and transport of soil has worldwide implications for agriculture, landscape stability, climate, natural hazards, and clean, renewable resources of water and air. Assured access to clean water and a healthy and safe environment requires an ethic of conservation and protection. The minimum scale in which these principles apply successfully is basin wide. These are the fundamental concerns of the Sino-US Centers for Soil and Water Conservation and Environmental Protection.

SOIL EROSION AND THE WATER & SOIL CONSERVATION IN THE LOESSIAL HILLY AREA OF SOUTHERN NINGXIA

1. General Situation of Soil Erosion The loessial hilly area of southern Ningxia, Situated at the south of Ningxia Hui Au-tonomous Region, middle-upper reaches of the Yellow River, part of Chinese Loess Pla-teau, covers an area of 1500 square kilometers with an annual mean temperature of 5-8℃,a precipitation of 300-500mm of which 70% taking place concentratively during the peri-od between June and September in form of rainstorm, The annual evaporation

On Soil and Water,Soil and Water Ecology,and Soil and Water Ecological Conservation

On the basis of discussing the positions and functions of soil and water in terrestrial ecosystem,the concept of soil and water ecology is put forward.It is thought that the integral concept of inseparability between vegetation and soil,water is an important feature of soil and water ecology.Meanwhile,a new definition for soil and water ecological conservation is given,and it is divided into four types:ecological,natural,production and construction.At the height of soil and water ecology,it is an active,organic and holistic concept of soil and water conservation,and is deepening and development of the cognitive view on soil and water conservation to understand and control soil and water loss from the source and linkage of elements,which will make soil and water ecological conservation enter a new era.

Roles of Science and Technology in Soil and Water Conservation in the New Era

Firstly,current situation and main problems of science and technology development of soil and water conservation were analyzed,and then roles of science and technology in soil and water conservation were studied. At last,exploration ways of roles of science and technology in soil and water conservation were proposed.

Application of Temporary Technology for Soil and Water Conservation in Crop Protection

The increasing of highway engineering construction makes soil and water loss surrounding highway and also influences the growth of crops around, To control soil and water loss, new engineering measures are put forward to protect soil and water and prevent crops from being damaged.

Position and Role of the Soil and Water Conservation in Building Ecological Province of Anhui

According to the strategic position of ecological environment in building ecological province of Anhui, we discussed the position and role of soil and water conservation in ecological environment construction and ecological province, and put forward development suggestion of soil and water conservation under new situation.

Study on Evaluation Method of Ecological Restoration for Soil and Water Conservation in Ningxia Hui Autonomous Region

On the basis of deeply understanding the domestic existing evaluation method of ecological restoration for soil and water conservation, under the premise of analyzing characteristics of current commonly used evaluation index of ecological restoration, based on the actual situation in Ningxia Hui Autonomous Region, taking objectivity, independence and operability as the principles, nine evaluation indexes were selected, and a set of comprehensive evaluation method of ecological restoration for water and soil conservation based on AHP was constructed. The hundred mark system corresponded with ecological restoration level, and the weight of each index in evaluation system was calculated according to comparison matrix constructed by frontline workers of soil and water conservation. The method could be used to determine difficult degree of restoration of the disturbed and destroyed ecosystem and the rationality of ecological restoration for soil and water conservation.

GIS-Based Multi-Criteria Evaluation to Identify Areas for Soil and Water Conservation in Lower Lake Bogoria Landscapes, Baringo County, Kenya

This study was meant to ensure that there is proper and efficient conservation of soil and water using geospatial tools to enable us identify priority areas to carry out conservation. Over the past years, various fields of study have established how critical it is to conserve these natural resources in the ecosystem and to ensure sustainability in not only green livelihoods but also to enhance living conditions of the life on earth. The aim of this research was to generate high priority sites for establishing soil and water conservation techniques in the Lower Bogoria Landscapes in Baringo, Kenya using GIS-based multicriteria decision analysis. Various criteria were analyzed to generate the final conservation priority sites, such as land use land cover, rainfall runoff, soil erosion and slope. The criteria were assigned weights using the AHP technique and overlayed using the weighted overlay tools to produce the final outputs. Land use land cover maps were generated using supervised maximum likelihood technique, rainfall run-off maps were generated using the SCS-CN method and soil erosion maps were generated using RUSLE model. The final soil and water conservation maps showed that high and moderate priority areas requiring the establishment of techniques and mechanisms to control soil erosion and conserve water increased from 1990 to 2020. In 2020, more than 50% of the total study area was classified as moderate to high priority for water and soil conservation. Soil and water conservation structures such as water pans, percolation tanks, farm ponds and stop dams should be constructed in such areas.