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1.
Despite numerous assessments of the sensitivity and resilience of drylands to degradation, there has been little research into the way affected communities innovate and adapt in response to land degradation. This paper shows how local and scientific knowledge can be combined to identify rangeland management strategies to reduce or adapt to land degradation. To achieve this, we have developed and applied a four‐stage social learning approach based on stakeholder participation in three degradation ‘hotspots’ in communal rangelands of the Kalahari, Botswana. This approach aims to collate, evaluate and apply both scientific and local knowledge on rangeland degradation and management options. First, current practice and possible management options were identified from the literature. Second, a series of semi‐structured interviews with rangeland users identified local knowledge of strategies to reduce and adapt to land degradation. Third, these options were discussed and evaluated with rangeland stakeholders in focus groups held across each study region. Finally, the outputs from these focus groups were used to produce rangeland assessment guides for each region that provided management options agreed to be locally relevant by both researchers and local stakeholders. The study found that the majority of strategies reported in the literature were not suitable for use by pastoralists in the Kalahari. However, many of the strategies suggested by stakeholders could only be applied effectively under common property regimes, giving impetus to the growing literature encouraging institutional reform to strengthen common property management regimes. The research stimulated a social learning process that combined knowledge from local stakeholders (both pastoralists and extension workers) with the scientific knowledge of researchers to provide a range of management options that could help land managers reduce or adapt to land degradation. By combining participatory research with insights from scientific literature in this way, more relevant results were provided than either approach could have achieved alone. Copyright © 2007 John Wiley & Sons, Ltd.  相似文献   

2.
Many elements determine land sensitivity to desertification, whose analysis requires multifactorial approaches to be used. The environmental sensitive areas methodology is a well‐known approach to estimate sensitivity to desertification that accounts for multiple interacting driving forces, conceived and validated in a Mediterranean environment. We show that the environmental sensitive areas methodology can be used, with minor modifications, in a tropical context, where it allows the discrimination among environments with different degree of susceptibility to degradation and resilience. The results obtained for the Dominican Republic show that 48·4% of its territory is critically sensitive to desertification, and 16·4% of it is highly critically sensitive to desertification, mostly because of intense and inadequate land use practices. Copyright © 2013 John Wiley & Sons, Ltd.  相似文献   

3.
Soil and its ecosystem functions play a societal role in securing sustainable food production while safeguarding natural resources. A functional land management framework has been proposed to optimize the agro‐environmental outputs from the land and specifically the supply and demand of soil functions such as (a) primary productivity, (b) carbon sequestration, (c) water purification and regulation, (d) biodiversity and (e) nutrient cycling, for which soil knowledge is essential. From the outset, the LANDMARK multi‐actor research project integrates harvested knowledge from local, national and European stakeholders to develop such guidelines, creating a sense of ownership, trust and reciprocity of the outcomes. About 470 stakeholders from five European countries participated in 32 structured workshops covering multiple land uses in six climatic zones. The harmonized results include stakeholders’ priorities and concerns, perceptions on soil quality and functions, implementation of tools, management techniques, indicators and monitoring, activities and policies, knowledge gaps and ideas. Multi‐criteria decision analysis was used for data analysis. Two qualitative models were developed using Decision EXpert methodology to evaluate “knowledge” and “needs”. Soil quality perceptions differed across workshops, depending on the stakeholder level and regionally established terminologies. Stakeholders had good inherent knowledge about soil functioning, but several gaps were identified. In terms of critical requirements, stakeholders defined high technical, activity and policy needs in (a) financial incentives, (b) credible information on improving more sustainable management practices, (c) locally relevant advice, (d) farmers’ discussion groups, (e) training programmes, (f) funding for applied research and monitoring, and (g) strengthening soil science in education.  相似文献   

4.
Soil erosion and associated sediment redistribution are key environmental problems in Central Argentina. Specific land uses and management practices, such as intensive grazing and crop cultivation, are considered to be significantly driving and accelerating these processes. This research focuses on the identification of suitable soil tracers from hot spots of land degradation and sediment fate in an agricultural catchment of central Argentina with erodible loess soils. Using Energy Dispersive X-Ray Fluorescence (EDXRF), elemental concentrations were determined and later used as soil tracers for geochemical characterization. The best set of tracers were identified using two artificial mixtures composed of known proportions of soil sources collected from different lands having contrasting soil uses. Barium, calcium, iron, phosphorus, and titanium were identified for obtaining the best suitable reconstruction of source proportions in the laboratory-prepared artificial mixtures. Then, these elements, as well as the total organic carbon, were applied for pinpointing critical hot spots of erosion within the studied catchment. Feedlots were identified to be the main source of sediments, river banks and dirt roads together are the second most important source. This investigation provides key information for optimizing soil conservation strategies and selecting land management practices and land uses which do not generate great contribution of sediment, preventing pollution of the waterways of the region.  相似文献   

5.
The People's Republic of China‐Global Environment Facility Partnership to Combat Land Degradation in Dryland Ecosystems promotes an integrated ecosystem management (IEM) approach to restore, sustain and enhance the productive capacity of dryland ecosystems. This paper provides an analysis and synthesis of the funding strategies, methods and approaches that have been applied and tested under the Partnership to pilot and scale up IEM and sustainable land management (SLM) practices in the western People's Republic of China under its first 10 years. On the basis of a mix of methods using literature reviews, data collection at selected pilot sites through household questionnaire surveys, stakeholder workshops and field sampling, the following lessons were generated: (i) mainstreaming of IEM into relevant policy and development frameworks has been the most effective way of mobilizing funding for scaling up of SLM; (ii) SLM best practices need to be combined with economic incentives for land users, and pilot demonstrations of SLM need to be integrated into larger investment programmes to achieve impacts and economies of scale; (iii) market‐based approaches to scaling up of SLM, such as payment for ecosystem services and public–private partnerships, have a role to play, but cost–benefit analysis need to be better integrated into payment schemes; (iv) the economic benefits of carbon sequestration are too low to fund eco‐compensation schemes on their own but can provide supplementary funding; and (v) land degradation and SLM monitoring and assessment systems should be multiscale to support decision‐making on SLM and to monitor impact from the local to the national level. Copyright © 2014 Asian Development Bank  相似文献   

6.
Deserts are known to mankind, but the term desertification has always been an elusive concept. It is now defined in the United Nations Convention to Combat Desertification (UNCCD) as land degradation in the drylands (land falling within arid, semi-arid and dry sub-humid areas) resulting from various factors, including climatic variations and human activities. This definition, which is now being used worldwide to describe desertification and its impacts, leads to the need to consider carefully the two-way interactions between climate and desertification. Dramatic changes in agricultural practices during the last several decades are one of the main driving forces for land degradation in the drylands and examples of land degradation are given for several regions around the world. The effects of desertification on climate have been described mainly in terms of changes in land use and land cover leading to land degradation; overgrazing; biomass burning and atmospheric emissions; agriculture's contribution to air pollution; forest and woodland clearing and accelerated wind erosion; anthropogenic land disturbances and wind erosion; and the impact of irrigated agriculture on surface conditions in drylands. It is equally important to consider the impact of dryland climates on soils and vegetation and the impact of climate change on desertification. It is important to adopt uniform criteria and methods to assess desertification and encourage monitoring of dryland degradation in all the regions around the world. To better understand the interactions between climate and desertification, it is also important to identify the sources and sinks of dryland carbon, aerosols and trace gases in drylands.  相似文献   

7.
There is an obvious need to incorporate biodiversity concerns into the policies and practices of sectors that operate outside protected areas, especially given the widespread devolution of power to local (municipal) authorities regarding land-use decision-making. Consequently, it is essential that we develop systematic (target-driven) conservation planning products that are both user-friendly and user-useful for local government officials, their consultants and the elected decision makers. Here, we describe a systematic conservation planning assessment for South Africa’s Subtropical Thicket Biome that considered implementation opportunities and constraints from the outset by developing - with stakeholders - products (maps and guidelines) that could be readily used for local government land-use planning. The assessment, with concomitant stakeholder input, developed (i) Megaconservancy Networks, which are large-scale conservation corridors of multiple ownership that achieve targets principally for biodiversity processes; (ii) conservation status categories (critically endangered, endangered, vulnerable, currently not vulnerable) for all biodiversity features, identified on the basis of available extant habitat to achieve conservation targets, and (iii) a conservation priority map which integrates (i) and (ii). This map was further interpreted for municipal-level decision-makers by way of corresponding guidelines for land-use in each of the conservation status categories. To improve general awareness of the value of biodiversity and its services, a handbook was compiled, which also introduced new and impending environmental legislation. Within 18 months of the production of these products, evidence of the effective integration, or mainstreaming, of the map and its guidelines into land-use planning has been encouraging. However, more effort on increasing awareness of the value of biodiversity and its services among many stakeholder groups is still required. Nonetheless, our approach of planning for implementation by considering the needs and obligations of end users has already yielded positive outcomes. We conclude by providing suggestions for further improving our approach.  相似文献   

8.
Conservation justice, a concept analogous to environmental justice, suggests that local communities are entitled to receive fair treatment and meaningful involvement in the development and implementation of conservation policy. In this study, of an urban conservation project in Cape Town, South Africa, we contribute to the ongoing conversation about the importance of community-based conservation approaches. Conservationists must work to plan and implement projects in ways that are not only acceptable to stakeholders, but inspire local community involvement in achieving conservation goals. Given its location in the impoverished Cape Flats region of metropolitan Cape Town and its unique ecological and conservation value, the Macassar Dunes Conservation Area warrants a conservation justice approach. We conducted semi-structured interviews with members of interested and affected communities, then analyzed stakeholder perspectives on biodiversity protection, fencing, and informal housing. The results suggest that despite disparity among groups in needs and perspectives, conservation projects have potential to deliver tangible benefits to all stakeholder groups. A belief in conservation is universal across stakeholder lines, but contrasting needs and perspectives of the studied groups lead to conflicting views on important issues of implementation. An understanding of different stakeholder groups’ specific needs and interests is therefore essential for successful implementation of sustainable urban conservation projects.  相似文献   

9.
Soil sealing is considered among the most dangerous of land degradation processes on global, European and national scales. Despite important policy documents aiming to mitigate this soil threat, it currently shows no signs of abating, and current efforts often do not result in appropriate implementation of soil sealing mitigation in spatial planning, which represents the subject area governing soil sealing. In this paper, we show a spatial decision support system – based on a Geospatial Cyberinfrastructure – with the aim of applying it as an operational instrument aiming towards soil sealing mitigation. The system has the ambition to impact on those who take decision over soil sealing; typically, these are not agriculture experts but rather spatial planners. This tool, focusing on mitigating such crucial land degradation, allows the users – via the Web – to produce ‘what‐if’ land planning scenarios thanks to the ‘on‐the‐fly’ modelling engines. Therefore, integrated geospatial quantitative data and procedures may be directly and freely used by planners. The tool has been applied to and tested in an area in the South of Italy. Results from two applications are reported: one addressing municipal planning and the other on a more detailed spatial scale. Furthermore, results include quantification of rural fragmentation, loss of soil ecosystem services and an estimate of soil sealing evolution over time. The tool was developed with the help of end users and indirectly explores a change of paradigm where soil science and landscape/urban planning work together to provide operational instruments that may be adopted by local communities in addressing soil sealing issues with a proactive approach. Copyright © 2017 John Wiley & Sons, Ltd.  相似文献   

10.
Some major developments in soil science since the mid-1960s   总被引:6,自引:0,他引:6  
A. R. Mermut  H. Eswaran 《Geoderma》2001,100(3-4):403-426
Although the science of soil was established about 150 years ago with the modern soil science taking off after the Second World War, the new Millennium has brought other challenges and new opportunities. Rapidly increasing population in countries that can least afford it have made them food-insecure. With inadequate inputs in agriculture, developing countries are degrading their lands rapidly and destroying ecosystems. Affluence in the richer countries has precipitated other problems hampering ecosystem functions and quality of land resources. These changing conditions have placed new demands on both the society and the soil science community. The latter has resulted in new areas of soil sub-disciplines such as land and soil quality, land degradation and desertification, cycling of bio-geochemicals, soil pollution assessment and monitoring etc. Advances in information technology have also enabled the science to meet the new demands of the enviro-centric world. In the last decade, noticeable changes are evident in methods and research priorities in the discipline. Soil resource assessment and monitoring is entering a new era, in terms of quality of information produced by new information technologies through the innovative use of Geographic Information Systems and remote sensing and significantly improving the acceptance and use of soil survey information. Electronic technology has dramatically increased the demand for and ability to process more data. Other innovations have resulted in quantitative approaches in soil genetic studies and demonstrated the integral role of soils in ecosystems. For global and regional resource assessment, concepts and procedures were refined. The World Reference Base for soil classification and the Global Soil and Terrain Database are the first steps towards standardisation and a more detailed assessment of global soils. The global assessment of human-induced land degradation and vulnerability to desertification are benchmark products of the databases. Environmental pollution and its effects on human and ecosystem health have become public concerns and soil science has contributed to localising, quantifying, and developing mitigation technologies to address the problems. The challenges of climate change and the charge to maintain ecological integrity have been met with technologies such as conservation tillage, agroforestry, precision agriculture etc. New concepts such as multi-functionality of land, soil quality, sustainability of agriculture and carbon sequestration, have emerged leading to new management strategies and an enhanced quality of life.  相似文献   

11.
生态退化研究的基本内容与框架   总被引:67,自引:1,他引:67       下载免费PDF全文
  相似文献   

12.
The need for reliable estimates of soil loss under different land management practices (LMPs) is becoming imperative in the Mediterranean basin to inform decisions on more effective strategies for land management. The effect of LMPs on soil erosion and land degradation has been investigated using experiments from November 2008 to November 2011 in an olive grove in central Crete (Greece). The study area was on sloping land with soils formed on marl deposits which are vulnerable to desertification because of surface runoff and tillage. The experimental design included three treatments with two replicates (3 × 5 m experimental plots) corresponding to the following LMPs: (i) no tillage–no herbicide application, (ii) no tillage–herbicide application and (iii) ploughing to 20 cm perpendicular to the contours. The following variables were monitored: surface water runoff, sediment loss, soil temperature at 10 cm, soil moisture content at depths of 20 and 50 cm, as well as selected climatic variables. The results show that the no tillage–no herbicide management practice gave the lowest sediment loss (1.44–4.78 g/m2/yr), the lowest water runoff (1.8–11.5 mm/yr), the greatest amount of water stored in the soil, the lowest soil temperature and the lowest desertification risk compared with the other treatments. Tillage resulted in the greatest sediment loss (13.6–39.2 g/m2/yr) and surface runoff (16.5–65.0 mm/yr), and an intermediate amount of water stored in the soil. In addition, this treatment led to the loss of soil thickness of 3.7 mm/yr because of ploughing. The results demonstrate the high risk of desertification in the investigated region and the methodology can be used in other Mediterranean areas as an assessment framework for evaluating land degradation and the impact of land management on soil erosion.  相似文献   

13.
As China becomes increasingly influential in international affairs, it is important to understand the unique characteristics of Chinese environmental values and policy processes. This is especially true given the rate and scale of China’s environmental impacts on natural ecosystems from local to international levels. Currently, however, Chinese conservation values, policies and practices are not well-integrated. We identify four systemic barriers to conservation in China that contribute to this poor integration: weak rule of law; unclear land tenure; top down government authority; and disconnects between scientific research and management implementation. To advance China toward an environmentally secure future, we suggest that combining traditional Chinese environmental values with contemporary science and international conservation practices will help to create a ‘Conservation with Chinese Characteristics’. We do not believe that traditional values should replace modern science and management. Rather, we suggest that, given the cultural and political conditions in China today, using traditional values to frame contemporary environmental science and ecosystem-based management may create stronger societal support for conservation implementation.  相似文献   

14.
China has long been experiencing intense land use/cover changes (LUCC). Undesirable land use/cover changes have resulted in widespread land degradation. This study examines the temporal and spatial dynamics of land use change and land degradation as evident from land use survey datasets (1991–2001). Six prominent land degradation processes were identified, namely: desertification, secondary salinisation, loss of agricultural use, deforestation, grassland degradation and loss of wetland. Rates of conversion were calculated and distribution patterns were mapped with the aid of GIS. The results showed that these land use changes have affected the wider environment and accelerated land degradation. It provided a more complete and up‐to‐date picture of China's land degradation which helps to develop improved conservation policies that combat land degradation and promote sustainable land management. Copyright © 2006 John Wiley & Sons, Ltd.  相似文献   

15.
东北黑土区沟道侵蚀现状及其防治对策   总被引:2,自引:1,他引:2       下载免费PDF全文
沟道侵蚀是土地退化最严重的表现形式,东北黑土区是中国除黄土高原外沟道侵蚀最为严重的区域,沟道侵蚀严重威胁东北区域农业生产和生态环境。该研究基于多年的研究积累,结合国家侵蚀沟治理专项调查和国家重点研发计划项目研究成果以及已有文献,系统总结归纳了东北黑土区沟道侵蚀特征、发展演变趋势及其危害;梳理出现有侵蚀沟治理措施的成功经验及失败教训,凝练提出区域侵蚀沟防治目标及4种主要侵蚀沟治理模式,并给出了适用范围及条件;同时提出了新时代东北黑土区侵蚀沟防治对策建议。该研究为区域现代农业发展和生态文明建设决策以及沟道侵蚀治理工程的实施提供了科技支撑。  相似文献   

16.
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   

17.
干旱区土地退化(荒漠化)作为全球面临生态环境挑战之一,对粮食安全、环境质量和区域自然资源管理至关重要。土地退化本质是人与自然因素协同作用下土地利用/覆被类型、数量、结构以及功能的改变而引起的生态服务价值降低,核心是土壤和植被的退化。一方面,人与自然共同作用下的土地利用覆被可以表征土地退化状态,另一方面植被-土壤生境时间序列相互作用过程进一步辅助土地退化过程诊断。因此,该文首先从覆被结构、退化类型和退化程度3个层次建立干旱区土地退化状态评价体系。其次,采用GF-1/WFV时间序列遥感影像,基于多端元光谱混合分解模型建立土地利用/覆被精细分类量化表征下垫面质量属性,并进一步利用植被-生境组分互动特征参数进行功能量化,综合评价民勤2015年退化类型和退化程度。最后,结合地面立地景观照片以及采样点实测数据,对土地退化状态评价结果进行绝对定标和交叉验证。结果表明:遥感评价识别土地退化类型和程度的能力分别为87.5%和78.7%。对于民勤旱地系统,沙化过程、沙-盐化过程是主要的土地退化过程,轻度沙化、中度沙化为主导退化程度。该方法为宽波段遥感国产高分1号卫星在旱地系统土地退化状态信息提取和深入应用提供科学依据和实证研究。  相似文献   

18.
华北农牧交错带土地沙漠化成因与土地利用调整对策   总被引:13,自引:4,他引:9  
从气候变化、土地利用等角度对华北农牧交错带典型区——内蒙古多伦县的土地沙漠化形成机制进行分析。对干湿指数、最大可能蒸散量等指标的分析表明该区域近30a来气候变化在一定程度上有利于沙化土地的恢复。1985年和2000年两期土地沙漠化、土地利用监测数据空间叠加和地统计分析表明,该区域15a来不存在明显的开荒和毁林等土地利用方式转型现象,利用方式未变化的土地占总土地的95.98%。严重沙化土地的91.39%发生在利用方式未变化的草地、耕地和未利用土地,三者沙化程度加重分别占该区所有沙化程度加重土地的55.16%、25.92%和10.31%。实地调查和遥感、统计等相关数据分析表明,耕地沙化主要是秋耕和农业大机械的应用为风蚀创造了条件,连年耕作和经济作物的种植促进了耕地退化;草地和未利用土地沙漠化主要因为载畜量过重和草原交通对草场的破坏。针对以上土地利用强度过大等造成土地沙漠化的原因提出华北农牧交错带土地利用调整策略。  相似文献   

19.
怀来盆地不同土地利用方式对土壤质量的影响分析   总被引:16,自引:4,他引:16  
基于对河北省怀来县官厅水库南北两岸8种主要土地利用类型的土壤养分、pH值和土壤容重等的分析,讨论了不同土地利用方式对土壤质量的影响,并评价了不同土地利用方式下的土壤退化程度。结果表明:怀来县官厅水库北岸的防护林地,由于合理的土地利用管理与保护措施,土壤容重最低,土壤养分含量高于其它几种土地利用方式;而由坡耕地撂荒后演替而来的草地,由于当地干旱寒冷多风的气候环境,土壤的母质条件以及缺乏有效的恢复措施等原因引起土壤质量继续退化;在长期不合理的土地管理措施影响下位于水库南岸的防护林地及葡萄园、果园、玉米地等土壤也发生较严重退化,表现为土壤容重、pH值显著增加,大部分土壤养分显著降低。土壤退化指数的计算结果也表明草地及南岸的玉米地、葡萄园的土壤发生了较严重的退化。在对数据进行处理分析过程中发现,土壤有机质、有机碳与全氮之间存在显著正相关关系。  相似文献   

20.
国外农田风蚀发生机理与防治技术的研究   总被引:16,自引:1,他引:16  
土壤风蚀是全球性土地退化的主要原因之一,也是世界上许多国家和地区的主要环境问题之一。该文简要回顾了国外对土壤风蚀发生机理、防治理念和技术的研究,提出林业上植树造林,牧业上防止草原退化,农业上实行保护性耕作是人类可以用来治理和控制土壤风蚀的3个重要原则。我国土壤风蚀和土地退化问题日趋严重,应在全国进行大力宣传,转变土壤风蚀治理的观念,使人们从思想上认识风蚀防治要从植树、种草、农田保护3个方面综合进行。同时,国家要从政策上、资金上为农田保护性耕作的大规模实施提供保证,促进保护性耕作在全国范围内的推广应用。  相似文献   

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