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1.
The problems of ecological soil rating with due account for the specificity of the contaminants (petroleum products) and the types of land use are discussed. The ways of solving these problems in Russian and foreign practices are considered. A scheme of the ecological rating of soils is suggested for different land uses; the allowable changes in the soil quality are discussed.  相似文献   

2.
Soil quality is considered to be the key element in the system of the agroecological assessment of lands. Soil quality is characterized by a combination of conditions ensuring sustainable crop yields and determining the ecological functions and stability of agrolandscapes. Soil conditions, i.e., the character of soilscapes and the soil quality, are integrated with all the other agroecological conditions in the system of land assessment. The soil quality reflects the integral effect of soil properties on the yield and quality of particular crops under certain climatic and landscape conditions and the level of agriculture; the ecological functions of soils are also taken into account. The productive capacity of agricultural land is the integral criterion of land quality; it is characterized by the yield of crops of particular quality at the given levels of agriculture intensity, energy inputs, and economic efficiency.  相似文献   

3.
The conceptual basis, methodology, and structure of ecological rating of permissible anthropogenic loads on soils in Ukraine are discussed. The main goals of the ecological rating are to ensure the preservation of optimum soil productivity and ecological functions, the rehabilitation of soil fertility, and the protection of soil and land resources. Conditions and criteria of ecologically safe land management are discussed. The main principles of the system of ecological rating—its reliability, hierarchy, differentiation and integration, reality, optimality and minimization, and adaptation—are considered. The methodology of hygienic and ecotoxicologic rating is analyzed. It is suggested that these approaches may be combined for the adequate assessment of soil contamination by heavy metals. The suggested scheme of ecological norms takes into account soil and climatic conditions, the character of land use, and other factors.  相似文献   

4.
The effect of soil management and land use change are of interest to the sustainable land management for improving the environment and advancing food security in developing countries. Both anthropogenic changes and natural processes affect agriculture primarily by altering soil quality. This paper reviews and synthesizes the available literatures related to the influence of soil management and land use changes on soil carbon (C) stock in Ethiopia. The review shows that topsoil C stock declines approximately 0–63%, 0–23%, and 17–83% upon land use conversion from forest to crop land, to open grazing, and to plantation, respectively. An increase of 1–3% in soil C stock was observed within 10 years of converting open grazed land to protected enclosures. However, there was a little change in soil C stock below 20 cm depth. There is a large potential of increasing SOC pool with adoption of land restorative measures. Total potential of soil C sequestration with the adoption of restoration measures ranges 0·066–2·2 Tg C y−1 on rain‐fed cropland and 4·2–10·5 Tg C y−1 on rangeland. Given large area and diverse ecological conditions in Ethiopia, research data available in published literature are rather scanty. Therefore, researchable priorities identified in this review are important. Copyright © 2008 John Wiley & Sons, Ltd.  相似文献   

5.
毛乌素沙地是典型的生态脆弱区,近年来针对其在榆林境内的沙地整治利用取得显著成效,也对土壤环境产生了深刻影响。为了探究沙地不同整治利用方式对土壤有机质的影响,该研究选取榆林市显性沙地,利用多光谱遥感影像及相关光谱指数,结合沙地土地利用变化特征,通过XGBoost机器学习方法,反演1990—2020年土壤有机质含量;分析不同土地类型下土壤有机质含量变化,通过半变异函数揭示了其空间变异性,厘清人为因素和自然环境的影响程度。结果表明,30 a间榆林5 460 km2沙地中超过半数得到整治和利用,沙地-草地是最主要的地类转变方式,建设用地面积增长最迅速;沙区土壤有机质含量上升,但整体呈现先增加后降低的趋势,有机质均值由0.34%增长至0.79%,近10年降低至0.51%;榆林沙区土壤有机质具有较强的空间自相关性。起初,人为利用对其有积极作用,但随着沙地的利用强度增大,对土壤有机质产生负向作用,进而致使其含量下降,面临土地退化危机。建议加强退化林草的修复改良,放缓建设用地开发力度,研究以期为沙地整治提供理论和实践借鉴意义,保护榆林沙地土壤环境安全。  相似文献   

6.
No-tillage (NT) has revolutionized agricultural systems because it has potential benefits including soil conservation and reduced production costs though saving in fuel, equipment, and labor. Soil quality is of great importance in determining the sustainability of land management systems, and soil microbial properties are becoming increasingly used to assess the effect of farming practices on soil quality due to their quick response, high sensitivity, ecological relevance, and capacity to provide information that integrates many environmental factors. In China, research and application of NT have developed quickly since 1970s. Numerous studies have been conducted in this country to evaluate the effect of NT on soil microbial properties. From these studies, it is evident that NT can lead to an increase in soil microbial size or activity or both and a consequent increase in soil microbial biomass in upland cropping systems. However, there are still several issues that remain unaddressed or inadequately specified. Further investigations are needed (1) to determine the effect of NT on soil microbial diversity by using molecular biological techniques in both upland and rice-based cropping systems; (2) to fully understand the changes of soil microbial properties with NT in rice-based cropping systems, especially for double rice cropping systems; and (3) to clarify the relationship between rhizosphere microbial properties and crop growth in NT rice cropping systems.  相似文献   

7.
Soil degradation, decrease in soil's actual and potential productivity owing to land misuse, is a major threat to agricultural sustainability and environmental quality. The problem is particularly severe in the tropics and sub-tropics as a result of high demographic pressure, shortage of prime agricultural land, harsh environments, and resource poor farmers who presumably cannot afford science based recommended inputs. Tillage methods and soil surface management affect sustainable use of soil resources through their influence on soil stability, soil resilience, and soil quality. Soil stability refers to the susceptibility of soil to change under natural or anthropogenic perturbations. In comparison, soil resilience refers to soil's ability to restore its life support processes after being stressed. The term soil quality refers to the soil's capacity to perform its three principal functions e.g. economic productivity, environment regulation, and aesthetic and cultural values. There is a need to develop precise objective and quantitative indices of assessing these attributes of the soil. These indices can only be developed from the data obtained from well designed and properly implemented long-term soil management experiments conducted on major soils in principal ecoregions.  相似文献   

8.
土地质量评估与监测: 土壤科学面临的新挑战   总被引:15,自引:0,他引:15  
Sustainable land management (SLM)is the key to harmonizing environmetal and ecolgical concerns of society with the economic realities of producing adequate food and fiber of high quality and ensuring a absi minimal quality of life.The aim of SLM is to maintain the integrity of the biophysical land resource base,but it can only be realized if land users understand the impacts of land management options on their lands but also on other off-site areas and can optimize the socioeconomic and environmetal benefits of their choice.To Facilitate this,the Contribution of soil suvery organizations would be through the assessment and monitoring of land quality.Land quality is a measure of the ability of land to perfor specific functions and is derived by an integration of soil survey information with other environmental,and if necessary,socioeconomic information.The desired reliability influences the operational scale of the assessment,Such an assessment would assist in:1) locating homologous areas for research sites or for transferring technologies;2) providing the geographic basis for systems analysis(e.g.modeling);3) serving as a basis for local,natinal and global resource assessment and monitoring;4) providing an ecosystem context for land use,assessments of temporal and spatial variability,and impact of human interventions;5)serving as a framework for more detailed assessment for all levels of interest;and 6) evaluating global issues such as food security,impacts of climate change,biodiversity montoring,and addressing desertification.Based on an evaluation of the progress made in soil resource inventories and considering the demands of the environment focused world,the paper considers the need for counteries to mount such a program.The authors believe that this is the next demand of soil science and that we can fulfill our soical contract by periodically providing such information on the state of a nation‘s land resource.  相似文献   

9.
Soils constitute one of the most critical natural resources and maintaining their health is vital for agricultural development and ecological sustainability, providing many essential ecosystem services. Driven by climatic variations and anthropogenic activities, soil degradation has become a global issue that seriously threatens the ecological environment and food security. Remote sensing (RS) technologies have been widely used to investigate soil degradation as it is highly efficient, time-saving, and broad-scope. This review encompasses recent advances and the state-of-the-art of ground, proximal, and novel RS techniques in soil degradation-related studies. We reviewed the RS-related indicators that could be used for monitoring soil degradation-related properties. The direct indicators (mineral composition, organic matter, surface roughness, and moisture content of soil) and indirect proxies (vegetation condition and land use/land cover change) for evaluating soil degradation were comprehensively summarized. The results suggest that these above indicators are effective for monitoring soil degradation, however, no indicators system has been established for soil degradation monitoring to date. We also discussed the RS's mechanisms, data, and methods for identifying specific soil degradation-related phenomena (e.g., soil erosion, salinization, desertification, and contamination). We investigated the potential relations between soil degradation and Sustainable Development Goals (SDGs) and also discussed the challenges and prospective use of RS for assessing soil degradation. To further advance and optimize technology, analysis and retrieval methods, we identify critical future research needs and directions: (1) multi-scale analysis of soil degradation; (2) availability of RS data; (3) soil degradation process modelling and prediction; (4) shared soil degradation dataset; (5) decision support systems; and (6) rehabilitation of degraded soil resource and the contribution of RS technology. Because it is difficult to monitor or measure all soil properties in the large scale, remotely sensed characterization of soil properties related to soil degradation is particularly important. Although it is not a silver bullet, RS provides unique benefits for soil degradation-related studies from regional to global scales.  相似文献   

10.
A method of determining the parameters of the soil state and assessing the quality of soils subject to anthropogenic loads was substantiated. An equation for the state function was derived in the general form, and a method was proposed for determining the equation parameters based on the interpretation of the experimental “dose-response” relationships. A schedule was developed for the environmental assessment of the soil quality. Procedures were substantiated and specified for assessing the state and quality of erosion-hazardous soils, the quality of the air with an unorganized dust source, the state and quality of the water on the basis of biotesting, the integrated assessment of the soil state under multiple loads, and the environmental-economic assessment of the quality of lands and waste disposal sites.  相似文献   

11.
基于农用地分等和土壤环境质量评价的耕地综合质量评价   总被引:12,自引:8,他引:12  
该文从耕地生态管护的角度出发,探讨了如何实现土壤环境质量评价与农用地分等成果的融合。基于土壤环境质量评价和农用地分等的理论和方法,该文提出了耕地综合质量评估技术,即在农用地分等所建立的等级体系基础上,引入土壤环境质量评价系数概念,进一步利用该系数对农用地利用等指数进行修订,得到耕地综合评价指数,并以河南省洛阳市为例作了实证研究。根据洛阳市耕地质量综合评价结果,与原农用地利用等别相比,无污染的耕地综合等别保持不变,有污染倾向的耕地综合等别有所下降,存在污染的耕地等别降为末等。这些评价结果可以为土地利用管理、环境污染防治规划将提供更有效的依据。  相似文献   

12.
黄土高原地区水土保持与生态建设的若干思考   总被引:4,自引:1,他引:4       下载免费PDF全文
 通过对黄土高原地区水土保持与生态安全的科学考察,在该地区水土保持科技成果与治理实践认识的基础上,对黄土高原地区水土保持与生态建设现状进行评价,总结水土保持与生态建设方面的主要经验,即:不能急功近利,必须认准目标,坚持不懈;基本农田建设是治黄减沙、促进稳定退耕还林还草、改善群众生活的一项关键措施;充分运用市场机制,强化机制创新,不断创新水土保持与生态建设的政策机制和组织形式。在考虑黄土高原资源与经济现状条件下,提出当前5个方面的发展思路:水土保持与生态建设的基本思路;遵从生态经济社会效益协调发展、生态效益优先的理念;必须建立有效的生态补偿机制;加强封育保护,充分发挥生态自我修复能力;加强城镇体系规划,促进城镇建设快速发展等。  相似文献   

13.
The analysis of modern Russian legislation in the sphere of environmental protection, management of natural resources, soil conservation, and land cadaster works has been performed. It is shown that a common federal approach to environmental impact assessments and soil quality assessments is virtually absent. Ecological indices are not taken into account in the federal land cadaster. Most of the recently adopted legislative regulations in this sphere have a technocratic character. The recent governmental regulations on land and environmental monitoring have still not been put into practice. To ensure soil conservation policy and protect soils as a component of the environment, a distinction should be made between the notions of soil and land in the legal documents. The basic principles of the proposed law “On Soil Conservation” are outlined. It is argued that a system of soil-ecological criteria should be elaborated for the proper assessment of soil quality. As a soil conservation service is absent in Russia, it is suggested that the Dokuchaev Soil Science Society should organize an association for the protection and rehabilitation of Russian soils.  相似文献   

14.
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   

15.
To ameliorate degraded red soils and restore their productivity, it is necessary to quantitatively assess the effects of different land uses on soil fertility. In this study, surface soil samples (0–20 cm) under different land uses were collected from an 18-year ameliorative experiment site of a eroded red soil in Lanxi county, Zhejiang province of southern China. The status of surface soil fertility was quantified with a ryegrass growth test in the greenhouse and by numerical analysis of twelve important fertility indexes. The soil fertility indexes were grouped into three major factors using a factor analysis, i.e., organic matter-nitrogen-structure, acidity and phosphate. By means of principal component analysis and cluster analysis of these fertility factors, the fertility of the eroded red soil as a function of land use patterns had the following decreased order: vegetable land>paddy field, cropping arable land and ryegrass land>tea garden>citrus garden>forestland>wasteland. The result suggested that organic matter, total N, available N, and water-stable aggregates were the main characteristics for fertility restoration of the eroded red soil. Soil fertility was most rapidly restored where the soil had been used as vegetable land, and least restored when left as wasteland. The results indicated that land use strongly affected the fertility restoration of eroded red soils because of its effect on the input of nutrients and energy, thus determining the speed and direction of soil fertility evolution.  相似文献   

16.
农用地土壤重金属超标评价与安全利用分区   总被引:8,自引:1,他引:7  
土地资源是大自然馈赠给人类的独特珍品,承载万物。开展区域农用地土壤重金属超标评价与安全利用分区、分类利用管控,促进区域土地资源合理、高效利用是新常态下耕地保护的基本要求。该文分不同p H值区间、8种不同地类,基于现行土壤环境质量评价和食品安全评价的众多标准集成土壤环境质量现状评价标准,以江苏省某市为例,运用单因子指数法、内梅罗综合指数法和潜在生态危害指数法开展土壤重金属超标评价,进而提出了安全利用等级划分方案和分区、分类利用与管理的管控策略。结果表明:将研究区农用地分为安全、基本安全、低风险、中风险和高风险5种综合分区,分别采取优先保护、综合监控、预警防控和限制利用等措施,以精细化管理思想为出发点,从源头控制、农艺措施调控、种植作物调整、地类转换以及土壤修复、综合整治等方面提出了各综合分区的安全利用管控策略。因此,开展区域农用地土壤重金属超标评价与安全利用分区研究为确保土地资源合理利用保护耕地提供了重要思路。  相似文献   

17.
The primary aim of this paper is to determine the spatial distribution of soil surface properties using high and medium resolution imagery data. Identification of these properties is important for determining environmental conditions resulting from anthropogenic influences, and for identifying land degradation processes within the study area which is an archaeologically important region situated to the north of Aksum (northern Ethiopia). Site specific field data were used to identify and verify the spatial distribution of soil surface properties such as soil colour, texture, and organic matter content obtained with IKONOS and ASTER images. As a result, distribution maps present the preliminary associations between land cover and soil characteristics as well as the location of archaeological sites. For all Aksumite cultural phases, the general pattern of ancient settlement remained the same and is similar to that of today: residential structures were built on well drained, high relief terrain.  相似文献   

18.
The status of tree vegetation in urban residential landscapes is worse than in natural forest ecosystems. The properties of the topsoil horizons undergo various transformations and the soil quality drops. The range of changes depends on the period of the settlement and the type of the use of the area. The most favorable conditions for plant development and the best ecological status of soils are seen in the regions with the shortest period of human habitation and low direct anthropogenic impact. Considerable degradation of chemical, biological, and physical soil properties in combination with high anthropogenic impact exerts an unfavorable effect on the status of soils and vegetation.  相似文献   

19.
Soil and land degradation in the tropics can be identified and described in terms of physical,chemical,and biological changes from its pristine state brought about by natural and anthropogenic influences.A characteristic of these ecosystems is their capacity to recycle nutrients through soil organic matter(SOM). Following disturbance through changed land management.SOM is rapidly mineralized and there is a cor responding decline in fertility and the variable charge component of the cation exchange capacity.As these ecosystems are strongly dependent on SOM for their functionality,changed land use can have irreversible impacts on the productivity of these systems.The paper focuses on quantifying chemical degradation throughbenchmaking using data from paried sites in tropical China and Thailand using surface charge finger printing.Using values taken from the fingerprint of an undistubed soil,an index of chemical degradation from ideality was calculated.Various management stratgeies that attempt to reverse degradative trends or improve poor quality soils in their natural condition are discussed.such as the ddition of natural clays and silicated materials.Results are present to whow the effect of each of the aforementional strategies on surface charge characteristics and associated increases in plant productivity.  相似文献   

20.
宁波市水土保持区划研究   总被引:2,自引:0,他引:2  
宁波市的水土保持区划工作始于2000年.当时主要依据宁波市地形地貌特点的水土保持区划,已不能适应新时期水土保持工作的需求.为科学指导宁波市今后的水土保持工作,在全国水土保持三级区划的基础上,结合宁波市的自然条件、水土流失发生发展趋势和社会经济发展对水土保持的需求,有必要重新进行水土保持分区.作者采用叠图分析法,将全市划分为北部农田防护水质维护区、中部人居环境水质维护区、东南土壤保持水质维护区和西部水源涵养生态维护区等4个不同的水土保持分区.北部农田防护水质维护区,重点加强耕地、园地和林地等具有重要生态功能土地的保护,改善平原河网水质;中部人居环境水质维护区,重点加强城市开发建设中土石弃渣和泥浆处置的管理,构建生态走廊,改善人居环境和河湖水质;东南土壤保持水质维护区,重点改造治理低质林地,完善沿海防护林建设,对经济林园地实施保土耕作措施,提高土地利用综合效益;西部水源涵养生态维护区,重点采取封山育林措施,充分发挥植被拦截泥沙、调蓄径流、涵养水源和治理面源污染的能力.通过合理的区划,以期科学指导宁波市今后的水土保持工作.  相似文献   

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