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1.
Nearly all of Europe is affected by soil erosion. A major policy response is required to reverse the impacts of erosion in degraded areas, particularly in light of the current climate change and water crisis. Soil loss occurs not because of any lack of knowledge on how to protect soils, but a lack in policy governance. The average rate of soil loss by sheet and rill erosion in Europe is 2·46 Mg ha−1 yr−1. To mitigate the impacts of soil erosion, the European Union's Common Agricultural Policy has introduced conservation measures which reduce soil loss by water erosion by 20% in arable lands. Further economic and political action should rebrand the value of soil as part of ecosystem services, increase the income of rural land owners, involve young farmers and organize regional services for licensing land use changes. In a changing World of 9 billion people with the challenge of climate change, water scarcity and depletion of soil fertility, the agriculture economy should evolve taking into account environmental and ecological aspects. © 2016 The Authors Journal of Land Degradation & Development Published by John Wiley & Sons Ltd.  相似文献   

2.
The Australian story of farmer innovation in Conservation Agriculture reveals a complex interplay of policy, economics, science, and farming. Farmer experimentation with Conservation Agriculture began in the 1960's and has continued to this day where around 80%-90% of Australia's 23.5 million hectares of winter crops are now grown using Conservation Agriculture principles. This remarkable achievement is the result of both sustained investment in agricultural research and development and farmer innovation. Australian economic settings and science policies have encouraged and facilitated farmer participation in the Conservation Agricultural innovation system. Australian farmers have embraced Conservation Agriculture because it has met their needs, maintaining productivity and profitability in the face of declining terms of trade, and sustainably intensifying production with enhanced environmental outcomes. Drawing on individual farmer case studies, the specific strengths of farmer innovation are identified and the enabling conditions necessary for farmer innovation to flourish are discussed.  相似文献   

3.
This paper examines the implications of changes in precipitation and land use to soil erosion from 1955 to 2002 in Basilicata, a hilly portion of southern Italy. Analysis of daily precipitation records reveals statistically significant trends using both non-parametric and parametric approaches. The inter-annual variability of precipitation increases in intensity; primarily between October and January. From 1955 to 2000, the length of dry spells greatly increased, while wet days decreased. A land use change map was produced for the three study areas using aerial photos (1955) and orthophotos (1997 and 2002), integrated with field surveys. Results show that land use is highly dynamic in Basilicata, especially due to the application of the European Union's Common Agricultural Policy (CAP) measures. The EU policies resulted in reclamation of badlands and degraded grasslands for agriculture, principally the cultivation of durum wheat. This farming practice and the abandonment of some of the remodeled areas have increased the risk of soil erosion and desertification processes, and is manifest in land degradation by rill networks and gullying.  相似文献   

4.
The change in the Common Agricultural Policy (CAP) of the European Union from product to producer support, including requirements for ‘good agricultural and environmental conditions’ and ‘greening’, is excellent. However, these requirements are now defined in rather general terms. Questions can be raised about suitable indicators, and there is a recognized need for effective management recommendations to support farmers in achieving the required ‘good’ conditions. These recommendations are bound to be quite different for different soils in different countries. A study of Dutch clay soils was based on a storyline describing current problems and management options for improvement, which were quantified using a soil–water–crop simulation model. Indicators were defined for agricultural conditions and suggestions made for the use of the model in a predictive mode to help farmers improve their soil management. Environmental conditions were judged by current environmental guidelines for water and air. When modelling, implicit assumptions that soils are homogeneous were shown to be unrealistic for these clay soils, requiring development of innovative methods and procedures, presenting a challenge for soil research.  相似文献   

5.
In mountain regions of Mediterranean European countries, recent economic and technologic changes have involved the intensification of crops, based on heavy land levelling and/or terracing, and the abandonment or marginalization of traditional land use management. These trends have been reinforced by the subsidy policies of the European Union. The objectives of the present research were: (a) to contribute to the understanding of agricultural trajectories and farming systems that are entirely transforming the social and environmental characteristics of Mediterranean mountain areas, focusing on the analysis of the main agricultural trajectories in a sample area of this environment (the Priorat region, NE Spain) over the last 20 years (1986–2005); and (b) to analyse the farming systems that coexist in the region with regard to the landscape impacts they involve and the influence of CAP subsidies in each one. A methodological approach based on the combination of multivariate statistical techniques was used to obtain a better knowledge of the heterogeneity of farming systems on a local scale. The results show that, although most farms cultivate a mosaic of traditional crops and have small mechanized areas, a minority group follows a high intensification and specialization strategy based on new mechanized‐terraced vineyards. This group only comprises 12 per cent of the farmers in the region, but owns 61 per cent of the new vineyard plantations and 42 per cent of the total agricultural land, receiving most of the subsidies from the EU vineyard conversion and restructuring policy (68 per cent of total Common Agricultural Policy (CAP) subsidies assigned to the region). Copyright © 2008 John Wiley & Sons, Ltd.  相似文献   

6.
The soil conservation movement in Brazil has been a major driving force in the continuing search for agricultural farming systems that are more sustainable than what we have today, particularly in tropical and subtropical areas. The development and adoption of Zero Tillage Conservation Agriculture (ZT/CA) was the key to the success of this movement, generating agricultural, environmental, and societal benefits.Adoption of the ZT/CA philosophy and technologies is currently practiced on more than 50% of the annual crop area. This is due to the work and innovations of pioneering farmers, agronomists, researchers, and consultants that were and are involved in these efforts. This extensive adoption of ZT/CA occurred after many unsuccessful efforts to mitigate against the devastating effects of soil erosion that were threatening the entire agricultural industry in Brazil. Technicians and farmers realized that erosion control required continual cover of the soil to guard against the torrential rain storms common to these regions. This triggered the efforts of soil conservation pioneers at different points in time and regions of Brazil.In southern Brazil, Herbert Bartz, watched his topsoil eroding away in torrents of runoff. This set him thinking and searching for alternatives, resulting in his adoption of ZT/CA farming in 1972. Ten years later in Brazil's centre-western savannah (Cerrado biome), farmers, researchers, crop consultants and agro-industry initiated efforts to expand cultivation into the very difficult production region of the Cerrados. This was successfully achieved through the pioneering work of agronomist John Landers, bringing experience from the ZT/CA farmer association networks in the south.These were the turning points in the sustainable development of annual crop farming in Brazil. Today, society recognizes the role of these pioneers as key to achieving social, economic and environmental sustainability. ZT/CA reversed the historically accelerating degradation of soil organic matter and soil structure by abandoning conventional tillage, thus improving soil physical and chemical characteristics. This was achieved by promoting cover cropping and permanent soil cover with crop residues, crop rotations, and complementary, environmentally suitable soil management technologies.  相似文献   

7.
The adoption of no till was a major turning point in the transformation of agriculture in Argentina. This paper describes the process of adoption of no till, and the impacts of this on agricultural production. Whereas previously, soil erosion was so extreme and pervasive as to threaten the economic viability and survival of the industry, today with the majority of production under no till, Argentina produces more than ever in the past. The paper also illustrates how, after first focusing on technology adoption (no-till), the system in Argentina has now broadened to include the concepts of Conservation Agriculture (CA) and Sustainable Land Management (SLM). These strategic moves have contributed to an agricultural industry in Argentina that is more economically and environmentally sustainable than that of the past.  相似文献   

8.
Conservation agriculture (CA) is often promoted as a set of cropping practices to reduce soil erosion and maintain soil fertility, while decreasing production costs and increasing crop yields. However, CA adoption is extremely low in Africa. Most investigations on constraints of its adoption leave out (i) the characteristics of CA as an emerging innovation and (ii) the wider institutional context. A comprehensive self‐assessment tool for a systematic evaluation of factors influencing the CA adoption process at the field, farm and regional scale in a variety of regional contexts in Africa is still lacking. In an attempt to fill this knowledge gap, this article presents the motivation, development and testing of a Qualitative expert Assessment Tool for CA adoption in Africa (QAToCA) and its application. QAToCA is directed to regional experts, research teams and managers of development projects with a focus on CA, and allows them to assess their CA activities along a systematic, expert‐based list of questions and criteria. Specifically, it aims at assessing the adoption potential of CA under the varied agro‐ecological, socio‐economic, cultural and institutional conditions of Africa as well as the specific supporting and hindering factors influencing this process. As an example, its application in Kenya and Tanzania identified a relatively high CA adoption potential. The following factors, however, are noticed to require further improvement: accessibility of markets for CA products and inputs; adaptation of machinery and seeds to the CA practices; introduction of quality implementation measures; and a renewed motivation (interest) among CA service providers. Copyright © 2012 John Wiley & Sons, Ltd.  相似文献   

9.
In Europe, land use changes follow public policies, and particularly the Common Agricultural Policy. To predict the effect of policies on agricultural practices, landscape, and ultimately biodiversity, requires understanding of the interactions between social, economic and ecological dynamics at regional scale. We studied by means of prospective scenarios the possible effects of agricultural changes on biodiversity in a Mediterranean upland. This area is characterised by extensive grasslands that have been maintained for centuries by agriculture and are now threatened by tree and shrub encroachment. We built four scenarios that describe possible changes in agricultural EU policies by 2030. We selected 15 bird species on the basis of a high natural heritage responsibility of the study area for these species and 45 plant species on the same basis plus local rarity and habitat vulnerability. We analysed how these species were affected by the four scenarios by considering changes in their habitats. For each scenario, we analysed the driving forces that determine land use changes. Landscape dynamics was modelled with a Generalised Linear Model combining environmental and land use factors. Most of the 60 selected species depend on open habitats. Only the scenario where public support was only granted if it provided environmental services had a positive impact on open habitats and their associated biodiversity. This ‘natural heritage’ scenario was also rated positively by local stakeholders. This approach sheds light on the interest of inter/transdisciplinary studies, scenarios, and stakeholder involvement in the definition of public policies for biodiversity conservation.  相似文献   

10.
【目的】研究灌溉定额、绿肥及其交互作用对河西绿洲灌区带田小麦、玉米产量和养分利用的影响,探寻适合灌区带田的水肥管理模式。【方法】试验采用裂-裂区设计,主区处理为灌溉定额,设三个水平为4500、6000和7500 m^3/hm^2;裂区处理为绿肥,设两个水平为不种绿肥和种植绿肥;裂-裂区处理为化肥,设两个水平,为不施化肥和施用化肥,化肥处理氮、磷、钾肥料用量分别为N 525 kg/hm^2、P2O5 150 kg/hm^2、K2O 90kg/hm^2。【结果】与4500 m^3/hm^2的灌溉定额相比,6000 m^3/hm^2和7500 m^3/hm^2的灌溉定额极显著增加了小麦和玉米的籽粒产量及其收获指数,增加了小麦和玉米籽粒的氮磷钾吸收量及其养分收获指数,小麦籽粒产量形成的氮生理效率和玉米籽粒产量形成的氮磷钾生理效率;极显著降低了小麦百公斤籽粒氮需求量和玉米百公斤籽粒氮磷钾需求量。绿肥种植与否对小麦、玉米籽粒产量均没有显著影响。种植绿肥极显著降低了玉米籽粒的收获指数和钾收获指数。灌溉定额4500 m^3/hm^2与种植绿肥交互作用下,玉米磷收获指数最低;灌溉定额6000m^3/hm^2与种植绿肥交互作用下玉米磷收获指数最高。种植绿肥处理显著增加了玉米百公斤籽粒氮磷钾需求量,显著降低了玉米百公斤籽粒磷钾生理效率。4500 m^3/hm^2灌溉定额下种植绿肥进一步加剧了干旱的胁迫程度,导致玉米百公斤籽粒氮、磷需求量显著增加,对钾的需求量极显著增加,磷生理效率显著下降,钾生理效率极显著下降。【结论】灌溉定额是河西绿洲灌区带田小麦玉米籽粒产量和收获指数、籽粒氮磷钾吸收量和氮磷钾收获指数、百公斤籽粒氮磷钾需求量和氮磷钾生理效率的决定因素。亏缺灌溉定额(4500 m^3/hm^2)下,种植绿肥会降低小麦/玉米带田籽粒产量及肥料利用效率。在6000 m^3/hm^2的灌溉定额下,建议河西绿洲灌区小麦/玉米带田应配合种植绿肥,提高产量和肥料效益。  相似文献   

11.
In response to the dust bowls of the mid-thirties in the USA, soil and water conservation programmes involving reduced tillage were promoted to control land degradation, particularly soil erosion. The farming and land management practices that were considered to adequately address soil and water conservation objectives were based on no-till seeding and maintenance of soil mulch cover. This collection of practices led to what became known as conservation tillage, although no-till systems by definition avoid soil disturbance by no-till direct seeding, and maintain an organic mulch cover on the soil surface.This article is an overview of achievements in soil and water conservation on agricultural lands through the experience derived from the adoption and spread of Conservation Agriculture (CA) world-wide. CA is an agro-ecological approach to sustainable production intensification. It involves the application of three inter-linked principles that underpin agricultural production systems based on locally formulated practices: (i) permanent no or minimum mechanical soil disturbance, which in practice entails direct seeding through mulch into no-till soils; (ii) maintenance of soil cover with crop residues and green manure crops, particularly legumes; and (iii) diversified cropping system involving annuals and perennial in rotations, sequences and associations.In 2011, CA had spread over 125 million hectares (9% of the global cropped land) across all continents and most agro-ecologies, including small and large farms. In addition, there is a significant area of CA orchards in the Mediterranean countries. CA is now considered to be a practical agro-ecological approach to achieving sustainable agriculture intensification. It offers environmental, economic and social advantages that are not fully possible with tillage-based production systems, as well as improved productivity and resilience, and improved ecosystem services while minimizing the excessive use of agrochemicals, energy and heavy machinery. While there are challenges to the adoption of CA, there is also increasing interest from producers, the civil society, donors and private sector institutions to further promote and service the uptake and spread of CA globally.  相似文献   

12.
In the subtropical highlands of Central Mexico, where the main crop is maize (Zea mays), the conventional practice (CP) involves tillage, monoculture and residue removal, leading to soil degradation and unsustainable use of natural resources and agricultural inputs. Conservation agriculture (CA) has been proposed as a viable alternative in the region, based on reduction in tillage, retention of adequate levels of crop residues and soil surface cover and use of crop rotation. This study began in 2009 when the highlands of Central Mexico suffered from a prolonged drought during vegetative maize growth in July-August, providing an opportunity for the on-farm comparison of CA with CP under severe drought conditions which 21 climate change models projected to become more frequent. Under dry conditions, CA resulted in higher yields and net returns per hectare as early as the first and second years after adoption by farmers. As an average of 27 plots under farmers' management in 2009, the maize yields were 26% higher under CA (6.3 t ha-1) than under CP (5.0 t ha-l). 2010 was close to a normal year in terms of rainfall so yields were higher than in 2009 for both practices; in addition, the yield difference between the practices was reduced to 19% (6.8 t ha-1 for CA vs. 5.7 t ha-1 for CP). When all the 2009 and 2010 observations were analyzed in a modified stability analysis, CA had an overall positive effect of 3 838 Mexican Pesos ha-1 (320 $US ha-1) on net return and 1.3 t ha-1 on yield. After only one to two years of adoption by farmers on their fields, CA had higher yields and net returns under dry conditions that were even drier than those predicted by the analyzed 21 climate change models under a climate change scenario, emission scenario A2.  相似文献   

13.
长三角地区稻麦轮作土壤养分对秸秆还田响应-Meta分析   总被引:1,自引:1,他引:1  
研究旨在明确稻麦轮作下秸秆还田对土壤基础养分的影响。以稻麦轮作系统为研究对象,采用Meta分析方法定量研究了土壤基础养分对秸秆还田的响应及其影响因素。结果表明,短期内(<2年)秸秆还田能够显著提升土壤有机碳和活性有机碳的含量,其中活性有机碳对秸秆还田的响应程度要高于总有机碳。低秸秆还田量(RS <3750 kg hm^-2和WS <3000 kg hm^-2)对土壤基础养分的提升效果不显著,而全量秸秆还田(RS 3000~6000 kg hm^-2和WS 3750~7000 kg hm^-2)能够显著提升土壤速效磷、有机碳和活性有机碳的含量。对于不同耕作措施而言,旋耕或翻耕措施均可以显著提升土壤有机碳的含量;此外,旋耕显著提高全氮和活性有机碳的含量,翻耕显著提高土壤速效磷和速效钾的含量。稻麦轮作下秸秆全量还田配合旋耕或者翻耕措施能够增加土壤基础养分含量,达到土壤地力培育的效果。  相似文献   

14.
低碳农业   总被引:5,自引:1,他引:5  
农业生产与全球气候变化紧密相关,农业是全球温室气体排放的第二大重要来源,同时,气候变化义影响着农业的发展.面对全球气候变暖,农业作为国民经济的基础产业,在节能减排中应当有所贡献.本文通过农业低碳发展的必然性,提出了低碳农业发展的领域、可能途径以及发展机制,为响应低碳经济,应对全球气候变化提供科学决策,促进现代农业由高碳...  相似文献   

15.
降雨侵蚀过程中红壤坡耕地地表汇流网络特征   总被引:2,自引:0,他引:2  
为研究降雨侵蚀过程中南方红壤区坡耕地地表汇流网络特征,应用亚毫米级高精度激光扫描和计算机数字图像处理相结合的方法在野外原位研究了南方几个典型母质发育的红壤模拟降雨条件下坡面汇流网络特征变化过程。结果表明:(1)在降雨侵蚀过程中,汇流密度和径流频度整体呈增加趋势,尤其是在第一场降雨过程中最为明显;(2)在第二、三场降雨侵蚀过程中的变化趋势因土壤性质和雨强的不同而出现差异;(3)在坡面侵蚀研究中,分形维数Ds可以较好的区别降雨前后整体汇流网络特征的变化。研究结果对南方红壤区坡耕地降雨侵蚀过程模拟与预测模型的研究、水土流失防治与水土保持规划设计具有一定的参考价值和借鉴意义。  相似文献   

16.
Recent concern over human-induced climate warming has activated bioclimatic research projecting the species-response to climate change scenarios. However, climate change is one of a range of human-induced environmental drivers controlling biodiversity, and for many species should be considered together within a framework of relevant stresses and threats. This paper critically assesses the sensitivity of epiphyte assemblages to regional gradients in climate, pollution regime and landscape-scale habitat structure (woodland extent and fragmentation). We examine lichen epiphytes associated with juniper scrub (a conservation priority habitat in Europe), sampled across a network of protected sites in Britain (Special Areas of Conservation). Results point to significant differences in associated epiphyte diversity between conservation priority sites. Historic woodland structure was identified as of greater importance than present-day woodland structure in controlling species composition and richness, pointing to an extinction debt among lichen epiphytes. Climatic setting was important in controlling species composition, but not species richness. However, we demonstrate that pollution regime exerts the dominant controlling force for epiphyte assemblages across regional gradients. As a corollary, we caution that for many species groups - for example those sensitive to pollutants, or landscape structure - an exclusive focus on climate is restricting, and that climate change models should expand to include a range of multiple interacting factors.  相似文献   

17.
The aim of the AIR-CLIM project is to perform an integrated analysis of the linkages between climate change and regional air pollution in Europe and to produce results that are relevant to European policy-making. Key elements of the analysis are on the impact side the exceedances of critical thresholds for air pollution and global change and on the cost side the estimates of costs to reduce emissions of greenhouse gases and air pollutants. The integrated modeling framework set up to meet these objectives consists of two state-of-the-art integrated models covering regional air pollution in Europe (RAINS) and global climate change (IMAGE), supplemented by new components. Based on a preliminary analysis it can be stated that climate change will make European vegetation in most regions less sensitive to acid deposition. Taking into account the emission trends the impacts of regional air pollution will decrease while the impacts of climate change increase. Different problems will be important in different regions: regional air pollution in Central and northern Europe, and climate change in southern Europe.  相似文献   

18.
Sesame, Sesamum indicum L. is used worldwide for cooking oil and food. The United States Department of Agriculture, Agricultural Research Service, Plant Genetic Resources Conservation Unit (USDA, ARS, PGRCU) conserves 1,226 accessions originating from Europe, Africa, Asia, North America, and South America. Sesame accessions were directly seeded to the field in Griffin, GA between 15 May and 01 June 2003–2007. At 50% maturity, 192 accessions were characterized for morphological, phenological, and reproductive traits during the regeneration cycles. High quality plants regenerated from all accessions produced 131 to more than 80,000 seeds per accession. Sesame can be successfully grown and regenerated in Griffin, GA. Coefficients of variation and principal component analysis revealed considerable variability among accessions for phenological, morphological and reproductive traits. Assuming appropriate levels of heritability, sufficient variation among sesame accessions exists for days to maturity, plant height, and reproductive traits among these sesame accessions to warrant breeding programs for new sesame cultivar development.  相似文献   

19.
Showy partridge pea, Chamaecrista fasciculata is used in the USA for cover cropping, ornate flowers in native gardens, honey crop, as an annual reseeding legume for restoration and conservation plantings, and wildlife food. However, its greatest potential may be as a bio-control plant for the control of mole crickets, cactus moth, and additional pest species. The United States Department of Agriculture, Agricultural Research Service, Plant Genetic Resources Conservation Unit (USDA, ARS, PGRCU) conserves 36 accessions originating from the USA.  相似文献   

20.
ABSTRACT

Conservation agriculture (CA) as recommended by the Food and Agriculture Organization of the United Nations consists of three components: minimum soil disturbance, soil cover, and crop rotation/association. CA was expected to become an effective countermeasure against water erosion in the Sudan Savanna, but it has not been adopted by local smallholder farmers. As markets for grain legumes (including cowpea) have not been developed in the Sudan Savanna, crop rotation/association should be considered impractical for these farmers. Therefore, we examined whether legume intercropping as a crop rotation/association component is necessary for preventing soil erosion in the Sudan Savanna. Three-year field experiments were conducted in runoff plots at Institute of Environment and Agricultural Research Saria station. The four treatments were conventional practice (full tillage, no sorghum residue mulching, and no intercropping), two-component CA (minimum tillage (MT) and sorghum residue mulching without intercropping), and three-component CA with velvet bean (VB) or pigeon pea (PP) intercropping. It was revealed that: (1) MT and sorghum residue mulching (without intercropping) effectively reduced the annual soil loss by 54% mainly due to the improvement of soil permeability by the boring of termites and wolf spiders found under the sorghum stover mulch; (2) intercropping in combination with MT and crop residue mulching had no effect on soil erosion control mainly because: (a) PP did not survive the long dry season; (b) VB did not serve effectively as a cover crop since soil loss was concentrated at the beginning of the rainy season when VB was still too small; (c) unexpectedly, in combination with MT and crop residue mulching, intercropping with VB did not increase mulch biomass, especially sorghum biomass which prompts the boring of termites and wolf spiders. These results demonstrate that the third component of CA, namely legume intercropping, is not always necessary; rather, the two remaining components – minimum soil disturbance and soil cover – are sufficient for soil conservation in the Sudan Savanna. This finding lightens the burden of adopting CA and thus facilitates its future promotion to the smallholder farmers in the Sudan Savanna.  相似文献   

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