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1.
Transnational land deals are among the most contested but inadequately understood topics. In this paper, we focus on the features of large‐scale transnational land deals (LSTLDs) in the Global South through an examination of Ethiopia. We apply a mixed method (qualitative and quantitative) research design.Results indicate that in 2005–2015, the government leased nearly 2·47 million ha of the country's approximate total 114 million ha area and offered 11·5 million ha of cultivable land to domestic and transnational investors. We explore the prevalence of LSTLDs deals by companies of the Global South, particularly entrepreneurs from India. Ethiopia's example validates emerging arguments on the rise of South–South investment deals rather than the established explanation of North–South capital flows. However, 75% of the land deals show poor performance. The study shows that LSTLDs have contributed to raising domestic agricultural production but have resulted in non‐performing loans of the banks of the host country. In sum, the land deals have resulted in financial grabbing, where Ethiopian banks end up with non‐performing loans and then must chase investors to settle the approximate €791 million in loans that investors borrowed for their projects. Copyright © 2017 John Wiley & Sons, Ltd.  相似文献   

2.
In the Gadarif Region of Sudan, destruction of the natural vegetation for agricultural expansion is one of the major causes of the degradation of renewable resources and the environment. This study identifies and analyses the farmers' attitudes and perceptions towards agricultural land degradation and abandonment. The cross‐sectional data collected from ten key informants and 41 large‐scale farmers focussed on the degradation and abandonment of mechanized agricultural land. The results of the study show that the respondents are well aware that soil degradation is in various forms are taking place on their cultivated agricultural land. This is based on their perception and interpretation of indicators such as weed infestation, poor soil fertility and soil compaction. Continuous cropping, mono‐cropping, rainfall shortage and the use of inferior seeds are the main reasons of land degradation as indicated by farmers. The main measures acknowledged to maintain and improve land productivity are repeated soil ploughing, abandonment/fallow periods and crop rotation. The study adduces evidence of widespread land degradation. The mitigation measures followed by the farmers may though not be sufficient to restore the soil fertility. The application of appropriate chemical fertilizers, sound crop rotation and long fallow periods can be recommended. Any management and research intervention regarding the problem of land degradation should; however, be concerted with the farmers' knowledge. Copyright © 2009 John Wiley & Sons, Ltd.  相似文献   

3.
The southwestern Ethiopian montane forests are one of the most species‐rich ecosystems and are recognised globally as a priority area for the conservation of biodiversity. Particularly, in contrast to the drier central and northern Ethiopian highlands, they have received little attention by researchers. Here, we review changes to agricultural systems in and around these forests that are known as the genetic home of coffee (Coffea arabica L.) and that are important to the livelihoods of many rural people who have developed traditional management practices based on agro‐ecological knowledge, religious taboos and customary tenure rights. We explored the impacts of conversions to agroforestry and cereal‐based cropping systems on biodiversity, soil fertility, soil loss and the socio‐economic conditions and culture. The increasing trend of cereal cropping, resettlement and commercial agriculture causes the deterioration of natural forest cover in the region and threatens biodiversity, land quality, sustainable, traditional farming practices and the livelihood of the local community. Large‐scale plantations of tea, coffee, soapberry locally known as endod (Phytolacca dodecandra L'Hér.) and cereals have resulted in biodiversity loss. Following the conversion of forests, cultivated fields exhibit a significant decline in soil fertility and an increase in soil loss as compared with the traditional agroforestry system. The establishment of a sustainable agricultural system will require a change in paradigm, whereby the intrinsic values of the traditional forest‐based agricultural system are recognised, rather than the ongoing mimicking of agricultural policies that were developed for the open fields of central Ethiopia. Copyright © 2016 John Wiley & Sons, Ltd.  相似文献   

4.
Land‐use dynamics in drylands are complex processes. In the context of a typical agropastoral village in northwestern Syria Im Mial, the effects of demographic and social changes, reduced soil productivity, changes in agricultural technologies and historical events on land use and land productivity are examined. Decreasing yields, mainly the result of reduced fallow periods and low investments in the land, and the deterioration of the grazing resources are the two main signs of the loss of land productivity in the area. The growing population forces the villagers to practise continuous rainfed barley cultivation with no or only occasional fallow, and without any application of plant nutrients. Also, technological changes, from the use of donkey ploughs and hand harvesting to less labour‐intensive and time‐consuming cultivation practices with tractors and combine harvesters, and the increased importance of stubble in the livestock diet have contributed to the reduction of the fallow periods. The villagers attribute the yield decreases mainly to the low rainfall in the area. The high rainfall variability discourages the fallowing of fields because continuous cultivation maximizes the chances for good harvests in years with high rainfall. There is also an expansion of cultivation into the less fertile and sloping traditional grazing areas. Population growth, increased numbers of livestock and the expansion of cultivated land into grazing areas has also put pressure on the grazing resources of the village. The possession of livestock is seen as a sign of wealth and the villagers aim to have large flocks of animals. For them, livestock is also an important means for investment of cash earned from off‐farm work, which is the main source of income for most of the households in the village. There is a recent trend of increasing levels of crop‐livestock integration with less free grazing that produces higher return to the land users. This may also have a positive effect on the restoration and conservation of the degraded natural traditional grazing grounds. The stabilization and productive use of the land resources in this dry environment requires the combined and interdisciplinary effort from both the land‐users and the policy‐makers. Copyright © 2001 John Wiley & Sons, Ltd.  相似文献   

5.
Recent trends and future demographic projections suggest that the need to produce more food and fibre will necessitate effective utilization of salt‐affected land and saline water resources. Currently at least 20 per cent of the world's irrigated land is salt affected and/or irrigated with waters containing elevated levels of salts. Several major irrigation schemes have suffered from the problems of salinity and sodicity, reducing their agricultural productivity and sustainability. Productivity enhancement of salt‐affected land and saline water resources through crop‐based management has the potential to transform them from environmental burdens into economic opportunities. Research efforts have led to the identification of a number of field crops, forage grasses and shrubs, aromatic and medicinal species, bio‐fuel crops, and fruit tree and agroforestry systems, which are profitable and suit a variety of salt‐affected environments. Several of these species have agricultural significance in terms of their local utilization on the farm. Therefore, crop diversification systems based on salt‐tolerant plant species are likely to be the key to future agricultural and economic growth in regions where salt‐affected soils exist, saline drainage waters are generated, and/or saline aquifers are pumped for irrigation. However, such systems will need to consider three issues: improving the productivity per unit of salt‐affected land and saline water resources, protecting the environment and involving farmers in the most suitable and sustainable crop diversifying systems to mitigate any perceived risks. This review covers different aspects of salt‐affected land and saline water resources, synthesizes research knowledge on salinity/sodicity tolerances in different plant species, and highlights promising examples of crop diversification and management to improve and maximize benefits from these resources. Copyright © 2008 John Wiley & Sons, Ltd.  相似文献   

6.
Salinisation of land resources is a major impediment to their optimal utilisation in many arid and semi‐arid regions of the world including Iran. Estimates suggest that about 34 million ha, including 4·1 million ha of the irrigated land, are salt‐affected in Iran as the consequence of naturally occurring phenomena and anthropogenic activities. The annual economic losses due to salinisation in the country are more than US$ 1 billion. With variable levels of success, different approaches—salt leaching and drainage interventions, crop‐based management, chemical amendments and fertilisers and integrated application of these approaches—have been used to enhance the productivity of salt‐affected soils in the Country. From sustainable management perspective, it is revealed from the past research that integrated salinity management and mitigation approaches have the potential to successfully address the complex problems of salt‐induced land degradation in Iran. As the growing need to produce more food and fibre for the expanding Iranian population necessitates the increased use of salt‐affected land resources in the foreseeable future, there is an urgent need to develop and implement a pertinent National Strategic Plan. In addition to establishing networks for monitoring spatial and temporal changes in soil salinity and water quality, this plan should integrate the management of salt‐affected environments into the overall management of land and water resources in the country. It should also address different management aspects of salt‐affected land resources in a holistic manner by considering the biophysical and environmental conditions of the target areas as well as livelihoods of the affected communities. The involvement of the communities will facilitate in developing a greater understanding about the potential uses and markets of the agricultural products produced from salt‐affected areas. Copyright © 2007 John Wiley & Sons, Ltd.  相似文献   

7.
The Central Rift Valley (CRV) is one of the most environmentally vulnerable areas of Ethiopia. Most of the lowland in the CRV is arid or semiarid, and droughts occur frequently. We studied the dynamics of land use and cover and land degradation by analyzing Landsat data from 1973, 1985, and 2006 using Geographic Information Systems and remote sensing techniques. The analysis revealed that in the last 30 years, water bodies, forest, and woodland decreased by 15·3, 66·3, and 69·2 per cent, respectively; intensive cultivation, mixed cultivation/woodland, and degraded land increased by 34·5, 79·7, and 200·7 per cent. The major causes of land use and cover change (LUCC) and land degradation in the area were population and livestock growth in regions of limited resources, unsustainable farming techniques, the Ethiopian land tenure system and poverty. Lake level and area decline, and accelerated land degradation are the major environmental impacts of LUCC observed in the CRV. The environmental and socio‐economic consequences of LUCC and land degradation are far‐reaching. As a result of the expansion of land degradation over time, agricultural productivity has decreased and worsened food insecurity (shortages) and poverty in the Ethiopian CRV. In addition, if current trends in LUCC continue, Lake Abiyata will dry up by 2021. A detailed study of the degradation amount in relation to soil erosion, sediment yield to the lakes and catchment characteristics should be made using adaptable models; so as to guide the implementation of comprehensive and sustainable land use management by giving more attention to erosion prone areas. Copyright © 2010 John Wiley & Sons, Ltd.  相似文献   

8.
土地整治项目提升耕地质量可实现潜力测算   总被引:11,自引:7,他引:4  
耕地质量潜力测算是土地整治项目设计的基础工作,其测算方法有待进一步研究。该文依据农用地分等方法和数据,利用自然等指数、利用等指数,构建可实现潜力测算模型,测算出经土地整治后自然等、利用等别提升的可实现潜力。以中江县土地整治项目进行了实证研究,在利用预评价法对项目区分等因素可改变和消除的幅度进行了可行性分析的基础上,测算了项目区耕地质量可实现潜力。结果表明,整治后项目区自然及利用等指数均可有所提升,分等单元的省自然等、利用等指数提升区间为171.24~605.34、89.30~232.96,国家自然等、利用等指数提升区间为161.10~471.67、62.26~162.09。按照划分等别区间分值转换后,省自然等、省利用等、国家自然等、国家利用等分别平均提升0.66等、0.63等、0.84等、0.62等。该研究方法符合当地土地整治实际情况,提高了耕地质量潜力测算的应用性,可为土地整治项目设计编制和耕地质量建设提供参考。  相似文献   

9.
农户土地利用投入变化及其土地利用意愿分析   总被引:3,自引:2,他引:1  
认识农户土地利用投入的变化规律,把握当前农户的生产意愿,对制订相关政策,确保国家的粮食安全具有重要意义。该文采用分层随机抽取样本的方法,基于湖北省咸宁市1 252个农户家庭的调查数据,从粮食生产过程中涉及到的劳动力、土地资源、农业机械、化肥与农药等生产因素方面,对1981年以来农户的土地利用投入要素的变化特征及当前的土地利用意愿进行了分析。结果表明:近30 a来,农户在土地利用过程中投入的劳动力与用于主要粮食生产的土地面积明显下降,而化学肥料与农药总投入量明显增加;经济因子与农机技术进步是驱动农户行为变化最重要的2个因素,劳动力转移与"三补一免"等惠农政策对农户土地利用投入变化的影响有限;农户农地利用的目标出现显著分化,传统"全民式粮食生产模式"正向"专业化规模化农户生产模式"转变,专业化规模生产农户应是国家惠农政策重点补贴与扶持的对象;国家在进一步促进土地流转的同时,如何有效稳定主要粮食作物的生产面积,需要更加积极的调控对策引导;随着边际土地从农地利用范畴析出,区域性生态好转出现新的机遇,国家宜出台生态用地整理的相关政策,提升区域性生态服务功能。  相似文献   

10.
This study classified land cover conversions by using quantitative change detection methods in the eastern Mediterranean coastal wetlands of Turkey. Three Landsat TM scenes acquired in 1984, 1998 and 2007 were analysed using image pairs of consecutive dates. The amounts of change were calculated for the periods from 1984 to 1998 and from 1998 to 2007, using binary change masks and supervised image classifications, in which eleven a priori defined land cover classes were used. Change areas accounted for 14.81 and 15.64 per cent of the total area, in the first and second periods, respectively. Conversions from/to sand dunes, mud flats and afforestation were by far the most extensive changes. Sand dunes and mud flats decreased, while afforestation and agriculture areas increased in the 23‐year period between 1984 and 2007. Five types of qualitative change were identified on the basis of land cover transformations within and between natural and anthropogenic systems. Type I changes, which indicated conversions from (semi)natural to anthropogenic systems, took place as agricultural expansion over coastal sand dunes, while Type II changes mostly occurred within agricultural systems. Type III changes included changes in human uses, leading to conversions from one anthropogenic system to another. Conversions between semi(natural) systems such as salt marshes and mud‐flats were typical Type IV changes. Type V changes were mainly due to conversions from agriculture to wetland categories or other semi(natural) cover types. Implications of these changes were discussed for management of coastal environmental resources. Copyright © 2011 John Wiley & Sons, Ltd.  相似文献   

11.
Participatory methods and community‐based approaches have an important role to play in combating land degradation. This paper follows a well‐defined participatory framework to identify key stakeholders and to select Sustainable Land Management approaches for reducing soil erosion and land degradation in the Troodos Mountains of Cyprus. Among the options suggested and evaluated by stakeholders, terrace rehabilitation had the best overall performance, followed by crop diversification and afforestation. Stakeholders agreed that the rehabilitation of dry‐stone terraces was the preferred option, as it is a practice with high environmental benefits and fits well in the local socio‐cultural context, despite the higher cost compared to other options. In the first year of implementing the approach, three mountain communities co‐organised hands‐on terrace maintenance events, engaging more than 160 people in rehabilitation activities. The community‐based approach has sparked the interest of people within and beyond the research site, and another series of events is scheduled for the coming season. This outcome indicates that social innovations can benefit from the integration of local and scientific knowledge, while participatory process can enhance the self‐confidence and organisational structures of local communities. Sustaining and enhancing the impact of the approach in the long‐run require developing local terrace maintenance institutions, actively engaging the youth in terrace management and improving the profitability of mountain farming through the differentiation of local products. Copyright © 2016 John Wiley & Sons, Ltd.  相似文献   

12.
耕地质量观的演变与再认识   总被引:9,自引:13,他引:9  
耕地质量对农业效益、粮食安全、耕地资源可持续利用能力具有重要影响。明确耕地质量概念、构成、特点和影响因素,对于加强耕地质量基础理论研究、推动土地整治与高标准农田建设、开展耕地质量管理实践工作具有重要意义。该文在梳理当前3种主要耕地质量观、剖析质量与土地质量内涵的基础上,阐述了新的耕地质量观。主要结论如下:1)当前主要存在基于耕地自然属性、自然-经济双重属性和多重属性的3种耕地质量观,他们既存在先后演化关系,又同时并存、互有区别;2)质量是产品一组固有特性满足要求的程度,土地质量是土地满足某种利用类型特定要求的能力和程度;3)耕地质量是耕地本身的特性满足农业生产并获取经济利润,以及满足人类福祉的程度,包括地力质量、工程质量、空间质量、生态环境质量、美学与文化质量;4)耕地质量具有生产性、内在性、综合性、空间性和时间性,耕地质量受到自然要素、工程要素和社会因素及其组合特征的影响。在耕地质量的理论研究与管理实践中,应充分考虑耕地质量的综合性,防止以偏概全;应将耕地质量的客观性与耕地质量需求的主观性有机统一;应根据耕地评价目的、监测的空间尺度和时间频率,科学构建耕地质量指标及评价指标体系,以科学合理地评价耕地质量状况。  相似文献   

13.
When farmers migrate yearly to a village to carry out intense farming during the rainy season, and thereafter return to a more permanent place of abode this is referred to as seasonal migration. The impact of such migration on land‐use/land‐cover change in an area within the Volta Basin of Ghana was examined using satellite image analysis and socioeconomic surveys. The most drastic land‐cover change involved the conversion of woodland to agricultural land, while there was also a general transition to less vegetation cover. Socioeconomic surveys revealed that most of the migration occurred during the post‐structural adjustment period in Ghana with declining soil fertility accounting for the highest per cent of causes of migration. Multiple regression results highlighted the role of population size and distribution, marketing of agricultural produce and technological evolution of the household in determining agricultural land‐use change. Policy initiatives that could lead to environment conservation are suggested. Copyright © 2004 John Wiley & Sons, Ltd.  相似文献   

14.
A framework for planning development strategies for sustainable land use in developing countries is proposed based on the carrying capacity concept. The rehabilitation of degraded land includes a stabilization and a restoration phase, with corresponding measures to be taken and funding modalities to be explored. Restoration measures focus on the rehabilitation of ecosystem functions, but are effective only when preceded or accompanied by measures stabilizing exploitation levels. Short-term benefits are required to ensure local participation, but may be counterproductive when long-term ecological rehabilitation is the major objective. Incentives are important policy instruments to enhance participation by rural communities in rehabilitation activities. Long-term economic, ecological and social (humanitarian) arguments, at a scale surpassing the local level, should receive more attention in the process of justifying investments for land rehabilitation. Some criteria and conditions to be met both at a macro-scale and at the local level are discussed.  相似文献   

15.
为系统分析和评价农业土地利用环境效应,了解农业系统中物质循环规律,提高物质利用效率,本文采用物质流分析方法,通过构建区域尺度农业土地利用系统的物质流分析框架和评价指标体系,以湖南省桃江县为案例区,综合评价了该区域农业土地利用系统中氮素利用效率及环境健康状况。结果表明:(1)1980—2013年,桃江县农业土地利用系统生产输入氮素量和环境输入氮素量显著增加,2013年比1980年分别增加了1.2倍和0.4倍;其中,生产输入方式是桃江县氮素输入总量的主要来源,占2013年总输入量的77%。(2)1980—2013年,桃江县氮素输出总量逐年波动增长,而产品输出氮素量却增加不多,但环境输出氮素量比1980年增长了1.4倍。(3)与此同时,桃江县农业土地利用系统氮肥投入强度逐年增长,至2013年其值达到328.4 kg·hm~(-2),超过了警戒值(250.0 kg·hm~(-2));此外,桃江县氮素物质利用效率逐年降低,物质生产效率还处于较低水平,还需进一步采取措施,调整农业结构,提高农产品附加值。(4)1980—2010年桃江县农业土地利用系统生态稳定性和环境健康质量逐年恶化,然而,在2010—2013年桃江县的环境健康质量有所好转,其氮素养分负荷由2010年的208.8 kg·hm~(-2)回落至2013年的154.1 kg·hm~(-2)。  相似文献   

16.
新疆玛纳斯县域土地利用变化对景观生态系统的影响   总被引:1,自引:0,他引:1  
21世纪初的玛纳斯县域土地利用面临新的政策和技术背景,采用遥感技术对2000年和2005年玛纳斯县域人类主要活动区各类景观进行对比分析,发现研究区内耕地、城镇景观面积出现大幅增长,林地、草地景观面积显著下降,“农林”、“农草”争水、争地的矛盾逐渐激化,水资源的供需处于“紧平衡”状态,区域景观生态系统的多样性、稳定性降低。分析表明导致玛纳斯县域景观生态变化的驱动因素主要包括当地气候条件的变化、农业相关政策的推行、农业节水灌溉技术的突破和农业生产合作形式的创新。  相似文献   

17.
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   

18.
中国省际耕地利用效率时空格局分异与机制分析   总被引:11,自引:5,他引:11  
科学剖析省际耕地资源利用效率时空格局分异及机制,对推进省际耕地资源集约利用具有重要的理论及实践意义。该文以中国省域(除港、澳、台)作为研究案例区,从投入和产出2个维度构建指标体系,运用改进DEA(data envelopment analysis)模型测度1994—2012年中国省域单元耕地利用效率值;综合利用ESDA(exploratory spatial data analysis)关联模型、R/S(rescaled range analysis)分形模型等方法分析省际耕地利用效率时空格局分异特征,并通过Tobit回归模型揭示效率时空分异的驱动机制。结果表明:1994—2012年中国省际耕地利用效率DEA最优比例相对较小,空间表征出东部高、中西部低的分布格局;东部沿海、北部沿海、东北地区综合效率较高,呈上升发展趋势,技术效率与综合效率变化较相似,而规模效率呈现先上升后下降态势;全局上省际耕地利用效率呈现空间正自相关,以空间集聚为主要分布模式;局部上可划分4种类型:H-H(high-high)效率区、H-L(high-low)效率区、L-H(low-high)效率区、L-L(low-low)效率区,其中H-H效率区主要分布在长三角、京津地区,并逐渐向珠三角演化,而L-L效率区主要集聚在中国西北地区;未来省际耕地利用效率将表现出继续增长的分形特征,且增长高值区集聚在中国东部、北部沿海;经济发展水平、农业科技进步是影响效率空间分异的重要因素,自然环境条件是效率发展差异的基础因素,而农户自身特征也会对效率时空分异产生一定冲击;最后,从推动技术进步、调整产业结构、耕地整理流转、补偿激励机制等方面提出省际耕地集约利用政策建议。  相似文献   

19.
农用地资源安全的监测-评价-预警系统   总被引:2,自引:5,他引:2  
随着人口的迅速增长和经济的快速发展,食物安全和农用地资源安全越来越受到学者和政府的关注。该文首先分析了农用地资源安全的含义及其产生原因,论述了农用地分等标准样地体系及其基本功能;结合全国农用地分等成果和现有的土地管理信息数据库,建立了农用地资源安全状况的监测网络、评价指标体系和方法;提出了确保农用地资源安全的监测-评价-预警-应急预案系统的结构框架,并分析了它对完善土地资源管理、切实保护农用地的重要作用。  相似文献   

20.
北京市平谷区农村居民点内部用地结构差异分析   总被引:4,自引:1,他引:3  
研究微观尺度农村居民点内部用地结构差异有利于因地制宜、差异化开展农村居民点内部用地结构调整,分类指导农村居民点用地科学规划与管理,提高农村居民点内部土地利用效率。本文以北京市平谷区为例,利用基于功能的农村居民点内部用地分类体系,调查了5个不同发展类型农村居民点内部用地结构差异,对比分析了其用地微观结构特点。研究发现:生活功能用地为农村居民点内部用地的基本结构,生产功能用地为衍生结构,生态功能用地为辅助结构,潜在功能用地为可变结构。受自然条件、区位条件、经济水平、产业结构与生计类型及政策条件等5维驱动因素共同作用,不同发展类型农村居民点内部用地数量结构、类型结构及信息熵差异显著,空间结构则呈现趋同性。随着社会经济发展水平提高,农村居民点用地结构表现出生活功能用地稳定、生产功能用地增加、生态功能用地减少的趋势。村庄规划应在把握其内部用地结构演变规律的基础上,注重可变影响因素调整,促进用地结构与其发展条件和谐统一。  相似文献   

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