共查询到20条相似文献，搜索用时 579 毫秒
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E. A. C. Costantini F. Urbano G. Aramini R. Barbetti F. Bellino M. Bocci G. Bonati A. Fais G. L'Abate G. Loj S. Magini R. Napoli P. Nino M. Paolanti M. Perciabosco F. Tascone 《Land Degradation \u0026amp; Development》2009,20(3):261-276
This study presents the main results and the methodology used in the creation of the atlas of the risk of desertification in Italy. A desertified area was defined as an unproductive area for agricultural or forestry use, due to soil degradation processes. An area at risk of desertification was a tract of the earth's surface which is vulnerable or sensitive to the processes of desertification. In a vulnerable land, environmental characteristics are close to that of a desertified area, but some factors (e.g. vegetation cover or irrigation), successfully mitigate the desertification process. On the other hand, sensitive land is a surface where the process leading to desertification is active, although the land is not yet unproductive. The DPSIR (Driving force‐Pressure‐State‐Impact‐Response) framework has been adopted as a reference. Using the national soil information system and socio‐economic layers, an atlas of indicators of desertification risks was created, which was organized into different soil degradation systems. 51.8 per cent of Italy was considered to be at potential risk of desertification. Some 21.3 per cent of Italy (41.1 per cent of the area at potential risk) featured land degradation phenomena. Specifically, 4.3 per cent of Italy is already unproductive; 4.7 per cent is sensitive and 12.3 per cent is vulnerable. In the territory at potential risk of desertification, unproductive lands, plus areas vulnerable or sensitive to soil erosion, are at least the 19 per cent. Areas affected by aridity also sum up to 19 per cent. Salt‐affected soils in Italy are estimated to cover >1 million ha. Irrigation can mitigate soil aridity and salinization, nevertheless, only about 15 per cent of the sensitive and vulnerable lands of southern Italy are actually equipped with irrigation networks. Copyright © 2009 John Wiley & Sons, Ltd. 相似文献
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Pasquale Borrelli Panos Panagos Cristiano Ballabio Emanuale Lugato Melanie Weynants Luca Montanarella 《Land Degradation \u0026amp; Development》2016,27(4):1093-1105
Understanding spatial and temporal patterns in land susceptibility to wind erosion is essential to design effective management strategies to control land degradation. The knowledge about the land surface susceptible to wind erosion in European contexts shows significant gaps. The lack of researches, particularly at the landscape to regional scales, prevents national and European institutions from taking actions aimed at an effective mitigating of land degradation. This study provides a preliminary pan‐European assessment that delineates the spatial patterns of land susceptibility to wind erosion and lays the groundwork for future modelling activities. An Index of Land Susceptibility to Wind Erosion (ILSWE) was created by combining spatiotemporal variations of the most influential wind erosion factors (i.e. climatic erosivity, soil erodibility, vegetation cover and landscape roughness). The sensitivity of each input factor was ranked according to fuzzy logic techniques. State‐of‐the‐art findings within the literature on soil erodibility and land susceptibility were used to evaluate the outcomes of the proposed modelling activity. Results show that the approach is suitable for integrating wind erosion information and environmental factors. Within the 34 European countries under investigation, moderate and high levels of land susceptibility to wind erosion were predicted, ranging from 25·8 to 13·0 M ha, respectively (corresponding to 5·3 and 2·9% of total area). New insights into the geography of wind erosion susceptibility in Europe were obtained and provide a solid basis for further investigations into the spatial variability and susceptibility of land to wind erosion across Europe. © 2014 The Authors. Land Degradation and Development published by John Wiley & Sons, Ltd. 相似文献
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Land degradation is a natural and socioeconomic cause–effect phenomenon that is widespread all over the world. This study investigated the socioeconomic factors and causes of land degradation (e.g. population growth and urbanization, poverty, overgrazing, pollution, biodiversity, erosion) in the eastern part of the Mediterranean region. The study revealed a significant land use change from agricultural and natural vegetation to urbanized areas due to the high population increase during the last ca. 80 years (51‐times the magnitude of the total built‐up area). The high poverty rate that exists in the area (57 per cent of the population can be classed as ‘poor’) has resulted in damaging environmental practices (overgrazing and intensive usage of natural plants); we found 83 per cent of the farmers admitted to the adoption of these practices. Poverty has also resulted in an inverse and significant correlation (at the 95 per cent confidence level) between holding size and the sale of land for urban uses. We also noted that 75 per cent of the smallholder farmers surveyed had sold their lands for immediate benefits to cope with poverty. This relation was affected by the education level of the farmers; we found a direct and significant (95 per cent confidence level) correlation existed between these factors. Overgrazing was practised by 70 per cent of the farmers and was found to be one of the most important environmental consequences of land use change (1600 ha have been transformed from natural grazing to built‐up (urban) in the study area). Socio‐economic induced land degradation demands efforts to improve farmer environmental awareness as well as environmental standards, laws and bylaws and the reduction of mismanagement of land. Copyright © 2010 John Wiley & Sons, Ltd. 相似文献
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Since 1990, agriculture in the five new federal states of Germany has experienced a fundamental structural change. As much as 10 per cent of the 6·2 million ha of previously intensively farmed agricultural land were set-aside abruptly. In the spring of 1991, a lysimeter trial (filled with soils common in the catchment area of the Elbe River), was set up to investigate the impact of set-aside on the water and solute balance. The studies proved that restricting agricultural use in areas previously farmed intensively by converting them into permanent or rotation fallow will result in measurable changes in deep percolation (ground-water recharge) and water quality in less than one year. The results of the lysimeter studies were extrapolated to calculate the effects of set-aside in a catchment area (about 2 500 ha) with similar meteorological and soil conditions. The calculations showed that increasing the area under rotation fallow from 8 to 15 per cent increases the nitrogen load of the stream draining the catchment by about 5 per cent. Copyright © 1999 John Wiley & Sons, Ltd. 相似文献
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《国际水土保持研究(英文)》2020,8(2):103-115
Soil is the basis of production in agriculture activities. The combination of intensive farming activities, improper farming practices, rainfall regimes, and topography conditions that taken place in agricultural land lead to the soil erosion problem. Soil erosion is the major constraint to agriculture that affects the yield production and degraded environmental sustainability. Furthermore, soil erosion that occurs in the agricultural area has jeopardized the sustainability of agriculture activities. Asia is one of the major agricultural producers in the world. It is essential to know how to mitigate soil erosion in Asian agricultural land. This systematic review aims to analyze the existing literature on research that has been done on control practices that had been taken in Asia agricultural land towards soil erosion. This article is guided by the PRISMA Statement (Preferred Reporting Items for Systematic reviews and Meta-Analysis) review method. The authors systematically reviewed the literature to study the control practices that been taken and tested to control soil erosion on the agricultural land in Asia. Accordingly, this systematic review identified 39 related studies about the topic based on the Web of Science and Scopus databases. This article divided the control practices into three main themes, which are agronomic practices, agrostological practices, and mechanical practices. The three main themes then produced a total of 11 sub-themes. Further specific and sustained research is needed to tackle this severe environmental problem through a better method, such as this systematic review method. The systematic review helps farmers and policymakers to implement the most practical approach to control and reduce soil erosion. 相似文献
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坡地开垦的径流泥沙响应 总被引：2，自引：0，他引：2
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. 相似文献
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退耕还林还草工程实施对洛河流域土壤侵蚀的影响 总被引：2，自引：0，他引：2
退耕还林还草工程是中国实施的重要生态环境建设与保护工程,对区域植被覆盖及土壤侵蚀产生重要影响。以洛河流域（陕北黄土高原部分）为研究对象,利用流域通用土壤侵蚀方程（RUSLE）,结合流域降雨、土壤类型、DEM、植被覆盖等数据,定量分析了2000—2010年退耕还林还草工程实施对流域土壤侵蚀的影响。结果表明:（1）洛河流域2000—2010年耕地面积减少,林地、草地面积增加,土地利用变化主要发生在2000—2005年;（2）洛河流域2000—2010年土地利用变化导致植被NDVI平均值增大,耕地变化区域植被NDVI值增加幅度高于耕地未变化区域,表明耕地变化区域植被NDVI增加对耕地区域总体植被NDVI值增加贡献较大;（3）降雨侵蚀力和退耕还林还草工程实施对土壤侵蚀具有明显的影响。受降雨侵蚀力增大影响,2000—2010年洛河流域土壤侵蚀呈增加趋势;不考虑降雨侵蚀力变化情况下,洛河流域土壤侵蚀呈减少趋势,反映出退耕还林还草工程实施对土壤侵蚀的减缓作用。 相似文献
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Identification of vulnerable areas for gully erosion under different scenarios of land abandonment in Southeast Spain 总被引：1，自引：0，他引：1
Abandonment of agricultural land is one of the main changes in Mediterranean land use. To mitigate runoff and erosion from abandoned land, it is necessary to identify locations that are vulnerable to erosion as a result of land abandonment. The objective of our study was to identify vulnerable areas for gully erosion using different scenarios of land abandonment in Southeast Spain. The study area was the Carcavo basin, a semi-arid catchment in the province of Murcia (Southeast Spain). A preliminary field survey confirmed the assumption that abandoned fields have more gully erosion compared to cultivated fields. This can be explained by the quicker concentration of runoff on abandoned land due to crust formation and reduced surface storage capacity. Next we simulated the spatial dynamics of land abandonment with a spatially explicit land use change model for the period 2004 to 2015 for four different land use change scenarios. The results of the simulation were used to identify vulnerable areas for gully erosion by a simple GIS-model based on the controlling factors of gully erosion. The potentially vulnerable areas for gully erosion increased for the different scenarios ranging from 18 ha to 176 ha. Most of the vulnerable areas are located around channel heads or along channel walls. The combination of more gully erosion on abandoned fields and an expected increase of land abandonment are potentially a big problem in relation to land degradation and reservoir sedimentation. The identification of vulnerable areas enables soil conservationists and engineers to mitigate gully erosion by applying preventive conservation practices. 相似文献
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浙江省低丘红壤区土壤侵蚀评价研究 总被引：2，自引：1，他引：2
本文以浙江省低丘红壤区为研究对象,利用卫星遥感影像构造削弱阴影等干扰的FCD模型,和混合像元法计算植被覆盖度的方法,进行水土流失研究。根据水利部颁布的《土壤侵蚀分类分级标准》,结合植被覆盖度、坡度、利用现状等因子进行土壤侵蚀强度评价。研究结果表明目前红壤区内植被覆盖情况良好,覆盖度基本在30%以上;整体水土流失程度较轻,但是耕地等农用地的侵蚀情况较为严重,特别是红壤区内耕地的强度侵蚀的面积占其总面积的17.65%。另外,耕作侵蚀也是土壤侵蚀非常重要的因素,在估算土壤侵蚀强度的时候也应重视。目前浙江省需要补充大量耕地以满足社会发展的需要,鉴于红壤水土流失易发的特点,在低丘红壤开发时要重视水土流失的预防和控制。 相似文献
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Effects of double drilling of small grains on soil erosion by concentrated flow and crop yield 总被引：1，自引：0，他引：1
Soil erosion on agricultural land and its detrimental environmental and economical effects has aroused increased interest among both the research and policy-making communities. The call for erosion control measures adapted to local farming practices is high, especially in Europe where farmers are reluctant to adopt soil conservation techniques. This study investigates a new technique for controlling concentrated flow erosion rates in the loess belt of central Belgium: i.e. double drilling of cereals in zones of concentrated flow. Cross-sectional areas of erosion channels as well as crop yield parameters in single- and double-drilled zones were compared. The technique is based on the combined effect of the increased density of plant shoots and roots for reducing soil loss. Results indicate that double drilling can reduce soil loss through concentrated flow by 25% on average and by up to 40% under optimal conditions. No net change in wheat grain yield was observed, and farmers who participated in the experiments were satisfied with the results and the easy application of the technique. Globally, benefits were larger than costs. However, the effectiveness of the technique in reducing soil loss by concentrated flow erosion seems to be topographically restricted. For positions in the landscape with a contributing drainage area larger than ca. 0.75 ha, the effectiveness of double drilling can be doubted. Double drilling should therefore be regarded as one possibility amongst others to reduce concentrated flow erosion rates in farmers’ fields. 相似文献
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P. Zdruli 《Land Degradation \u0026amp; Development》2014,25(4):373-384
The Mediterranean region covers about 854 million ha, but only 118 million (or 14 per cent) are suitable for agricultural production. In North Africa and the Middle East (MENA), agricultural land covers about 5 per cent; in Egypt and Algeria, it occupies less than 4 per cent and, in Libya, less than 2 per cent of the total national land area. Across the Mediterranean region land use divides between natural pastures/rangelands (ca. 15 per cent), forests and woodlands (ca. 8 per cent), with the ca. 63 per cent remaining desert sands, shallow, rocky, saline, sodic soils and areas effectively sealed by urbanisation. Land degradation is a severe problem in most Mediterranean countries. Estimates for the period 1961 to 2020 show that although the Mediterranean population is likely to more than double, ca. 8.3 million ha of agricultural land (7 per cent) may be lost as a result of continued urbanisation and land degradation. If these estimates are correct, agricultural land per capita would more than halve from ca. 0.48 ha (1961) to ca. 0.21 ha in 2020. Food security is likely to become increasingly problematic, especially in the MENA countries, which require a major reassessment of their agricultural development policy. Copyright © 2012 John Wiley & Sons, Ltd. 相似文献
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针对煤矸石山复垦地水土流失严重的问题,在山西阳煤集团三矿280煤矸石山坡面上选取7种植被恢复模式,以裸地为对照,设置水土流失试验样方,观测不同植被恢复模式对土壤侵蚀和养分流失的影响。结果表明：与裸地相比,不同椬被恢复模式均对矸石山坡面土壤侵蚀和养分流失具有明显控制效果;下坡段的乔灌混交模式防治坡面侵蚀的作用优于上坡段的草本和灌木;减少水土流失的效果上坡段为荆条 > 紫花苜蓿 > 沙打旺 >草木樨,下坡段为刺槐+柠条、刺槐+荆条和榆树+紫穗槐,但这3种植被模式对减少水土流失的差异不显著;通过偏相关分析,影响养分流失的因索依次为土壤侵蚀量 > 径流量 > 坡度 > 坡长;不同植被恢复模式对煤矸石风化物中速效养分质量系数也具有明显的影响。 相似文献
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The semi-arid loess hilly–gully region in China has an extremely vulnerable ecological environment. Inappropriate land use — crop farming, overgrazing, and plantation forestry - has worsened soil erosion, intensified water shortage, and hence impeded the ecological conservation and agricultural development of the entire region in the past. Optimizing land use and vegetation cover and spatial pattern is conducive to achieving both ecological and economic goals in terms of controlling soil erosion, using water resources rationally and raising agricultural productivity. Changchuan Watershed, a typical small catchment in the semi-arid loess hilly region, was selected as the case study area to analyze the impacts of land use and land cover structure and associated spatial pattern on soil erosion and water consumption in the Watershed, through field investigation and model simulation. Land use structure was optimized by multi-objective programming, using remote sensing (RS) and geographical information system (GIS) techniques, analytic hierarchical programming (AHP) and expert consultancy. The digitized optimum spatial pattern embodying rationally-proportioned land use structure was obtained through GIS-aided redistribution of land use types. The optimized land use structure re-apportioned woodlands, shrublands, grasslands, and croplands at 3.7%, 38.6%, 49.4%, and 6.3% of the land area respectively, compared to the current land use structure of 2.4%, 38.6%, 24.0%, and 12.6%, respectively, in the Changchuan Watershed. In the optimized land use spatial pattern, croplands are mainly located in the riverside plain and check-dammed valleys and grasslands are widely distributed in the lower reaches of the basin, while shrublands are appropriately established in the middle and upper reaches of the river. A comparative analysis shows that the optimized land use structure, with well-designed spatial pattern is able to reduce soil erosion, enhance the utilization of water resources and raise agricultural productivity. 相似文献
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《Communications in Soil Science and Plant Analysis》2012,43(18):2250-2255
This study was aimed at assessing the causes of the gully erosion and its effects on the agricultural lands in the arid region of southeastern Iran. In this study, we have used geologic maps in scales of 1:50,000 and 1:250,000, aerial photographs on a scale of 1:20,000, field observation, and GPS (global positioning system). Three soil samples were taken from 25, 50, and 75% of the gully length at each location and analyzed for pH, electrical conductivity (EC), exchangeable sodium percentage (ESP), sodium absorption ratio (SAR), cation exchange capacity (CEC), calcium (Ca), and soil texture. The causes of gully erosion, its effects on agricultural lands, characteristics of the gullies, soil depth, and vegetation of each area were evaluated. The results show that several parameters, including poor rangeland vegetation cover, overgrazing, human activities, intensive and short-period rainfall, improper land use, improper irrigation design, improper discharge of water in the channels, and soil characteristics influence the gully erosion. Gully erosion causes severe damage to agricultural lands, including soil loss, increase in surface runoff, lower soil water-holding capacity, lower quality and quantity of water, lower groundwater table, and lower agricultural production. It increased migration from villages to cities and increased socioeconomic problems and poverty. It also caused substantial damages to construction sites such as bridges, roads, and settlements as well as rivers and reservoirs and increased sediment concentration in rivers. 相似文献
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J. R. Fan J. H. Zhang X. H. Zhong S. Z. Liu H. P. Tao 《Land Degradation \u0026amp; Development》2004,15(4):411-421
An assessment of the effectiveness of soil conservation practices is very important for watershed management, but the measurement over a small area does not necessarily represent the truth over a large area. Monitoring of soil erosion and analysis of sediment delivery were carried out in the Lizixi watershed (which is typical of the Upper Yangtze Basin, China), using remote sensing and a geographic information system (GIS). Land‐use and land‐cover maps were prepared by an interpretation of 1986 and 1999 images from SPOT and Landsat TM. Slope‐gradient maps were created from digital elevation model (DEM), while merged images of SPOT and Landsat TM were used to obtain land‐use information. The area of soil erosion was classified by an integration of slope gradients, land‐use types and vegetation cover rates, and soil erosion rates and their changes were calculated in a grid‐based analysis using an Erdas GIS. The change in sediment delivery ratio was estimated based on the changes in soil erosion rates from both monitoring and the truth survey. There was a reduction in soil erosion rate of 4·22 per cent during a 13‐year period after soil conservation practices were adopted in the Lizixi watershed. The amount of sediments transported into rivers has decreased by 51·08 per cent during the same period due to an integrated application of biological and engineering measures. The comparison of soil erosion severity between pre‐conservation and post‐conservation revealed that soil loss has been obviously diminished and the measures were quite effective. Copyright © 2004 John Wiley & Sons, Ltd. 相似文献
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黑土区是中国重要的粮食产区，掌握黑土区耕地质量状况，探索耕地质量与土壤侵蚀的耦合协调发展关系，可以进一步保持耕地的健康发展。为探讨黑土区耕地质量与土壤侵蚀的耦合协调发展关系，以嫩江市为研究区，利用层次分析法及CRITIC权重法确定22项选取指标的综合权重，通过综合质量指数法构建地学特征、土壤特性、土壤健康、基础设施建设及植被生长5个维度的质量指数，引入TOPSIS模型分析确定嫩江市耕地质量等级，开展黑土区障碍因子诊断、侵蚀状况模型评估及耦合协调研究。结果表明：1）嫩江市以中等级耕地为主，占总耕地面积的29.6%，高等级耕地较少，占比为10.1%。耕地质量等级存在较大差异，集聚类型以不显著为主，且在市域内呈现散碎分布的空间格局。2）根据障碍因子诊断发现，指标层中土壤pH值、排水能力、灌溉能力、地块连片度及比值植被指数指数的障碍度较高，是制约耕地质量的主要因素。准则层中耕地的基础设施建设指数障碍度最高，对于耕地质量具有显著影响。3）嫩江市西南部区域土壤侵蚀强度相对较弱，侵蚀较为严重区域主要分布在嫩江市的北部及东部区域，空间分布格局呈现东北高西南低。4）空间耦合协调分析发现，耕地质量与土壤侵蚀强度的空间耦合度介于0.22～1.00之间，具有明显的耦合响应特征，呈现出一定的空间差异性，总体上土壤侵蚀与耕地质量处于良好的协同发展状态。研究为松嫩平原农业健康生产及黑土区耕地质量监测评价提供参考依据。 相似文献
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喀斯特山区土地利用变化与土壤侵蚀耦合关系研究——以毕节试验区为例 总被引：2，自引：1，他引：2
利用RS与GIS技术,提取地类、坡度和植被等3个因子的数据信息,模拟1990—2010年毕节试验区的土地利用过程和土壤侵蚀变化过程,并运用叠置分析和转移矩阵分析的方法,分析了土地利用变化过程中土壤侵蚀的响应特征,揭示土地利用变化及土壤侵蚀变化的关系。结果表明:毕节试验区土地以林地、耕地、草地为主,耕地面积不断减少,林地和建设用地面积不断增加;土壤侵蚀以轻度、中度侵蚀为主,整体呈现改善的趋势,尤其是退耕还林后,土壤侵蚀的面积与强度均不断降低;土地利用变化与土壤侵蚀具有密切的联系,耕地是土壤侵蚀发生的主要土地类型,耕地的减少与土壤侵蚀呈正相关关系,林地面积变化与土壤侵蚀具有较好的相关性,但在退耕还林的初期,土壤侵蚀的强度略有增加,草地增加与土壤侵蚀负相关,增加草地有利于土壤抗侵蚀能力的增强。研究喀斯特山区土地利用与土壤侵蚀的耦合关系,有利于有限的土地资源的合理配置和喀斯特地区的生态保护,为区域土地规划及水土保持等宏观决策部门提供理论支撑。 相似文献