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661.
Globalfreshwaterresourcesaregettingincreasinglyscarce ,enlargingtheareaofdrylandandmakingthesituationworse .Thus,theresearchanddevelopmentondrylandagro technologyiscatchingpeople’sincreasingattention .DrylandareasinChinaaremainlydis tributedinnorthern 1 6 provinces (municipalities ,autonomousregions) ,whosedrylandagri cultureplaysanimportantrolein 2 1stcenturyChina’sagriculture .Majorissuesfacedbydrylandagro techdevelopment Inearly 1 980s ,addressingtheseverescarcityofwaterinthenorthernCh…  相似文献   
662.
The Role of the Concept of the Natural (Naturalness) in Organic Farming   总被引:1,自引:3,他引:1  
Producers, traders, and consumers oforganic food regularly use the concept of thenatural (naturalness) to characterize organicagriculture and or organic food, in contrast tothe unnaturalness of conventional agriculture.Critics sometimes argue that such use lacks anyrational (scientific) basis and only refers tosentiment. In our project, we made an attemptto clarify the content and the use of theconcepts of nature and naturalness in organicagriculture, to relate this conception todiscussions within bioethical literature, andto draw the implications for agriculturalpractice and policy.Qualitative interviews were executed with arange of people in the field of organicagriculture and with consumers of organicproducts, on the basis of a list of statementsabout the meaning of the concept of naturalnessformulated by the authors. Based on the resultsof the interviews, we distinguished 3 aspectsof the concept of naturalness: natural as theorganic (life processes), natural as theecological, and natural as referring to thecharacteristic nature of an entity. We relatedthese conceptual aspects to three mainapproaches within the field of organicagriculture: the no chemicals approach, theagro-ecological approach, and the integrityapproach. It became clear that these approachescan also be recognized in the change ofattitude of farmers as they convert fromconventional to organic agriculture, and in theattitudes of consumers of organic foodproducts.We conclude that the idea of ``naturalness' canbe used to characterize organic agriculture andto distinguish it from conventionalagriculture, but only if naturalness not onlyrefers to not using chemicals but also toecological principles and respect for theintegrity of life. Thus perceived, theprinciple of naturalness can also serve as aguide to future developments in the field oforganic agriculture. As part of the holocentricethics of organic farming the value ofnaturalness has three dimensions: a cognitiveone, an emotive one, and a normative one.  相似文献   
663.
This paper examines the ethical andsocial questions that underlie the present UKdiscussion whether GM crops and organicagriculture can co-exist within a given regionor are mutually exclusive. A EuropeanCommission report predicted practicaldifficulties in achieving sufficientseparation distances to guarantee lowerthreshold levels proposed for GM material inorganic produce. Evidence of gene flow betweensome crops and their wild relatives has beena key issue in the recent Government consultation toconsult on whether or not to authorizecommercial planting of GM crops, following theresults of the current UK farm scale trials.The admixture of imported Bt transgenes intolandrace varieties of Mexican maize alsopresents difficulties. An ethical evaluationis made of the claim that organic growersshould expect protection from adventitioustraces of GM constructs in their products. Towhat extent – on either side of the debate –can any particular group in society set upagricultural standards for itself that mayeffectively restrain others from an otherwisejust business? The assumptions behind notionslike ``purity'' and ``contamination'' areexamined, together with their underlying viewsof nature and human intervention. The 2001UK Agriculture and Environmental BiotechnologyCommission report is relevant to theseissues. While the Government wishes to promotethe UK biotechnology industry and is underpressure from US claims of trade restraint, astrong organic lobby demands purity from GMcontamination. Does this adversarial framingof the issues reflect broader public opinionin the UK public consultation? Inarriving at policy decisions, the role of thevirtue of tolerance is considered inpost-modern and Christian ethical contexts.  相似文献   
664.
This paper outlines the advantages of integrated crop–livestock systems and unsolved problems that need to be studied further. The discussion is subdivided by ecozone with consideration of arid and dry semi-arid areas with extensive livestock management; moist semi-arid and semi-humid areas where integrated crop–livestock systems are common; and humid areas where swine and poultry often predominate. To maintain soil organic matter in all ecozones, efficient recovery and use of nutrients from animal manures, crop residues and green manures is essential. In extensive systems in dry zones, animals transport nutrients from grazing areas to cropland, while in moister regions that are more intensively farmed, the emphasis is on the efficiency of nutrient recovery. Specific research questions relating to the overall ecosystem, nutrient cycling, plants, and animals are posed.  相似文献   
665.
河南省由于农业人口基数大,农业人口增长迅速,人口素质和结构不够合理。土地、水及其它自然资源没有得到充分的利用,且污染比较严重,对河南省脆弱的农业生态环境造成了严重的不良影响。要改善河南省农业生态环境现状,促进河南省农业人口、资源与生态环境的协调发展,就要从控制人口的增长,提高农业劳动者科技文化素质;推广绿色农业技术,保护农业资源;发展综合养殖生态工程,合理回收利用生物质资源;健全环境保护机制,加强监控力度四个方面入手。  相似文献   
666.
段颖  陈金涛 《环境科学与管理》2010,35(9):105-107,111
根据指数计算分级方法,依据农业生态环境特点,建立指标体系。根据黑龙江省现状算出其农业生态环境质量指数,再进行指标等级评价分析。用定量方法了解黑龙江省农业生态环境现状。分析农业生态环境问题,提出解决措施,改善农业生态环境,保证黑龙江省农业可持续性发展。  相似文献   
667.
黑龙江省是全球三大黑土地之一,富饶美丽的黑土地是发展有机农业最好的地方。文章分析了黑龙江省发展有机农业的优势和基础条件,划分了各类种植区域,探讨了有机农业发展方向,为黑龙江省发展有机农业提供了参考依据。  相似文献   
668.
进入21世纪生态农业已经成为农业发展的大势所趋,作为国家振兴东北的省份,黑龙江省应当结合实情,发挥自身的优势,进一步发展生态农业经济,加强生态环境建设,促进黑龙江省经济又快又好发展。发展生态农业不仅可以推动黑龙江新农村建设,而且有助于经济的可持续发展和生态城市的建设。建设生态省、打造"生态龙江"是实施可持续发展战略的不断深入,也是实现经济、社会、环境和资源协调统一发展,提高综合竞争力的关键。  相似文献   
669.
为了加快推进西北内陆灌区发展循环农业,在临泽县平川镇三二村研究和总结了绿洲玉米种子繁殖田与荒漠区日光温室间的循环农业模式。该循环模式主要包括制种玉米、牛、沼气、荒漠区日光温室4个接口,实现了"玉米—牛—沼气—日光温室"的循环,具有良好的经济效益、社会效益和生态效益。  相似文献   
670.
景观生态学在农业景观生态规划和设计中的应用   总被引:1,自引:0,他引:1  
从景观生态学的基本原理入手,阐述景观生态学在农业景观生态规划中的应用。认为农业景观规划设计不仅关注景观的“土地利用”、“土地肥力”以及人类的短期需求,更强调景观的生态价值和美学价值及其带给人类的长期效益。农业景观生态规划设计的中心任务就是创建一个可持续发展的整体区域生态系统。中国生态农业是典型的持续农业。依据景观生态学原理和典型生态农业模式经验,探求中国生态农业景观特征及其景观生态学意义,进而针对农业景观的生物生产、经济发展、生态平衡和社会持续4大功能,提出农业景观生态规划应遵循的5项原则,即提高异质性原则、继承自然原则、关键因子调控原则、因地制宜原则和社会满意原则。  相似文献   
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