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61.
SUMMARY

An assessment is made of various grassroots development initiatives in Latin America which show that agroecological technologies can bring significant environmental and economic benefits to small farmers and rural communities in the region. Examined initiatives offer new ways of enhancing the multifunctional attributes of traditional agriculture through greater per unit area productivity and environmental services obtained in complex, integrated agroecological systems that feature many crop varieties, together with animals and trees. If such experiences were to be scaled up, multiplied, extrapolated, and supported in alternative policy scenarios, the gains in food security and environmental conservation would be substantial. The challenge now is to mobilize science, institutions and the right policies to increase the productivity of smallholder farming systems, while preserving the resource base and at the same time empowering local communities.  相似文献   
62.
中国生态农业与绿色食品   总被引:8,自引:0,他引:8  
傅宪 《四川环境》1994,13(2):61-64
本文从农业环境问题和食品安全性出发,阐述了中国生态农业的兴起及特点,绿色食品生产的要求,生态农业与绿色食品的关系。介绍了几种可用于开发绿色食品的优化生态模式。  相似文献   
63.
Substantial conflict exists over water management and allocation in the Platte River Basin of Nebraska. An interdisciplinary computer simulation model, representing the water quantity, water quality, environmental, and economic dimensions of the conflict, was developed in order to analyze the tradeoffs among allocation scenarios. Most importantly, decisionmakers and interest groups were involved in model development. Simulation results for a base case and two scenarios are presented. One scenario favors protection of instream flow for wildlife; the other favors water diversions for agriculture. Impacts of the instream flow scenario, as measured by the amount of land irrigated, groundwater levels, the amount of wildlife habitat for cranes and catfish, and net agricultural benefits did not differ greatly from those of the base case. However, impacts of the diversion scenario were substantial. On the negative side, instream flows and wildlife habitat declined an average of 39 percent; while, on the positive side, groundwater levels and net agricultural benefits each increased 6 percent. The modeling process was successful insofar as it promoted an understanding among the highly diverse interest groups of the systems nature of the Basin. One agreement on a water diversion schedule among three of the parties has been reached, partly as a result of this process. More comprehensive compromises have not yet been forged. Our experience, however, indicates that modeling success at the policymaking level depends more on the extent to which the policymakers understand the model than it does on model sophistication.  相似文献   
64.
Biotechnology increases commercialization of food production, which competes with food for home use. Most people in the world grow their own food, and are more secure without the mediation of the market. To the extent that biotechnology enhances market competitiveness, world food security will decrease. This instability will result in a greater gap between rich and poor, increasing poverty of women and children, less ability and incentive to protect the environment, and greater need for militarization to maintain order. Therefore, biotechnology should be discouraged. An active program to protect and strengthen local food production and to decrease reliance on industrial agriculture should be promoted.  相似文献   
65.
我国农业水旱灾害的时间分布及重灾年景趋势预测   总被引:21,自引:4,他引:21  
分析了我国 1970~ 1999年农业水旱灾害的时间分布特征。分析结果表明 :在研究时段内 ,我国农业自然灾害总体上呈增长态势。该时段可划分为两个明显的阶段 :80年代中期以前 ,总灾、水灾及旱灾对农业生产的危害较轻 ;80年代中期之后 ,呈现出影响范围广、损失增大的趋势 ,重灾年份明显增加。旱灾和水灾是威胁我国农业生产最为严重的自然灾害 ,尤以旱灾为甚。我国农业遭受旱灾威胁的范围多年基本不变 ,而旱灾受灾率波动明显 ,成灾率逐年增长 ,这与近几年农田水利设施建设缓慢、灌溉能力降低有关 ;水灾受灾率和成灾率具有特别显著的同步特点 ,表明水灾致灾能力强 ,一旦发生 ,极易成灾 ,水灾危害加剧与防洪、抗洪能力低下及生态环境恶化有关。各灾种的受灾率和成灾率呈正相关关系 ,表明我国农业生产系统的抗灾能力总体上较弱。  本文还用灰色系统理论的建模方法 ,建立了农业总受灾率 -总成灾率、水灾受灾率 -成灾率、旱灾受灾率 -成灾率的重灾年景灰色灾变GM(1,1)预测模型 ,对未来 10年我国农业灾害趋势进行了预测分析。灰色预测结果表明 ,2 0 10年之前 ,除 2 0 0 3,2 0 0 6年水旱灾害危害较小外 ,其它年份均为灾情严重年份 ,其受灾率和成灾率均高于近 30年的平均水平。其中 ,2 0 0 4 ,2 0 0 7年将为水灾重  相似文献   
66.
The article discusses agricultural practices in sub-Saharan Africa, especially in terms of maintaining soil fertility. It disagrees with alarmist tendencies in the current debate, exaggerating the state of soil impoverishment in the African region. Nor does it subscribe to the idea that the remedy lies primarily in a massive influx of chemical fertilisers, especially phosphorus.
Instead, the article advocates a more balanced approach, where soil nutrient replenishment, as an improvement in natural capital, is but one part of the investment African agriculture needs. To achieve sustainable rural livelihoods, other forms of capital are also required, such as physical capital, i.e. infrastructure (roads, means of communication); financial capital in the form of credit and savings schemes; and human- and social capital, especially improved access to information and knowledge for farmers as well as improved local organisation and empowerment.
The article reviews nine case studies, taken from different climate zones in the region and representing different soil conditions. All case studies were projects using the participatory learning and action research (PLAR) method, which is discussed in detail.  相似文献   
67.
在计划经济体制下.农业不是也不可能成为一个独立产业,其结果只能是社会效益可观、经济效益甚微甚至倒贴,吃苦的是农民。社会主义市场经济体制的逐步确立,为农业走向市场带来了希望,首要的是确立市场经济观念。丘陵地区大搞农业资源的综合开发是使农业走向市场的重要途径,综合开发上了水平,实现“三高”农业就大有希望。搞农业综合开发的途径很多,但都必须以市场为导向、科技为先导、经济效益为中心,大搞农业产加销一条龙、贸工农一体化是提高农业综合开发整体水平、实现“三高”农业的必要途径。  相似文献   
68.
“白色农业”与“三色农业”兴起及中国农业产业化方向   总被引:4,自引:0,他引:4  
本文从白色农业与三色农业概念入手,阐述了白色农业的创新意义,提出了我国农业产业化的战略构想。  相似文献   
69.
Farmers in Sahelian countries are confronted with a variety of soil fertility and management problems. During the last two decades, NGOs have worked with farmers and research institutions to develop and test practices that will increase food production, while at the same time enhance the natural resource base.Since 1987, The Rodale Institute (RI) has worked closely with farmers' associations and government institutions to promote regenerative agriculture-farming systems that prioritize the use of local resources while improving them as they are used to grow food, using agro-ecological methods. The Senegalese Agricultural Research Institute has collaborated in this program as a partner of RI. The Senegal Regenerative Agriculture Resource Center model has been applied as a new and viable approach that builds on traditional knowledge and farmer-to-farmer exchange.Research results on soil conservation and improvement have shown that fields spread with amended animal manure or compost yield greater harvests than fields farmed with traditional methods.  相似文献   
70.
The great majority of farmers in Latin America are peasants who still farm small plots of land, usually in marginal environments utilizing traditional and subsistence methods. The contribution of the 16 million peasant units to regional food security is, however, substantial. Research has shown that peasant systems, which mostly rely on local resources and complex cropping patterns, are reasonably productive despite their land endowments and low use of external inputs. Moreover analysis of NGO-led agroecological initiatives show that traditional crop and animal systems can be adapted to increase productivity by biologically re-structuring peasant farms which in turn leads to optimization of key agroecosystem processes (nutrient cycling, organic matter accumulation, biological pest regulation, etc.) and efficient use of labor and local resources. Examples of such grassroots projects are herein described to show that agroecological approaches can offer opportunities to substantially increase food production while preserving the natural resource base and empowering rural communities.  相似文献   
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