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281.
中国农业可持续发展的现实路径   总被引:2,自引:0,他引:2  
作为中国可持续发展总体战略的重要组成和优先领域,农业可持续发展是我国现代农业发展的理性抉择和根本出路。农业可持续发展的实质是谋求农业生态系统中各要素及其相关各系统之间、系统与外部环境之间的有序化与整体性持续运作,其核心是保持农业系统的良性循环和生产力的可持续性。当前我国现代农业可持续发展的困境和挑战主要表现为:农业经营制度的先天不足和设施装备的落后使得农业发展根基不牢;人力、资本及科技等要素的缺失导致农业发展支撑力量严重不足;耕地和水资源短缺成为制约农业持续发展的瓶颈;农业生产与市场需求的结构性失衡及农产品质量安全问题使得最终产品难以满足社会需求。从可持续发展理念出发,本文认为中国特色现代农业发展的现实路径应立足于中国现实的资源及社会约束条件,着重从以下几个方面入手,即重视人力资本培育;大力推进农业合作化;加快农村金融创新;提升农业科技水平;发展劳动密集型农业;践行生态农业理念。  相似文献   
282.
Precision agricultural fertilization technique at small scale is the key for regional cultivated land protection and management. Taking Dingzhuang Town (located in Guangrao County, Shandong Province) as a case study, this article explores the precision agricultural fertilization technique at small scale. First, three main cropping systems are identified via field investigation, namely wheat–maize–soybean, garlic–maize and cotton. Then, application amount of fertilizer N, P and K under the three cropping sys...  相似文献   
283.
Up to now, several scientific works have noted that the organic sector resembles more and more conventional farming’s structures, what is widely known as the “conventionalization” thesis. This phenomenon constitutes an area of conflict between organic farming’s original vision and its current reality and raises ethical and social questions concerning the structure of agricultural systems of production and their interactions with the socio-economic and natural environment. The main issue of this dialogue is the concept of sustainable agriculture, which for scientists and policymakers is a means to express their vision of a better agriculture. In this article we focus on agricultural sustainability in the context of capitalist production as conducted by the two subsystems of agro-industrial system. As we have proposed in this article, the relationship between organic agriculture, defined by two essential components (prevention and direct marketing), and the agro-industrial complex, defined by two subsystems, indicates the degree of agricultural sustainability. The investigation of this relationship can be extremely useful as it may lead those involved in the discussion of sustainability to identify the key aspects of sustainable agriculture. In order to investigate the interaction of organic farming with the agro-industrial complex, a survey was conducted in Central Macedonia, Northern Greece, involving local organic farms. The results of our study indicate that a large proportion of organic producers did not differ substantially from their counterparts in conventional agriculture in so far as their relationship with the agro-industrial complex is concerned. Finally, this research highlights two scenarios for the evolution of organic farming. The first is the full absorption of organic farming to the existing economic system and the second one is the development of organic farming in a radically opposite direction to conventional farming.  相似文献   
284.
蒋学辉  章强华 《灾害学》2001,16(4):67-71
病虫草鼠是农业的主要生物灾害。本文分析了浙江省农业生物灾害的现状和今后农作物重大病虫害的发生趋势,提出了农业有害生物的控制对策。  相似文献   
285.
基于能值计算的循环农业发展个例分析   总被引:3,自引:0,他引:3  
能值分析能够更好地量化分析和评价循环农业。利用该方法对湖北省武汉银河生态有限公司的循环农业进行了实证分析。结果表明,实施循环农业后的集约养殖场结合农地流转发展起来的“猪-沼(能)肥-地-菜(藕、果、粮)-鱼-村”六位一体的循环农业典型模式,与实施循环农业前当地分离的水稻、小麦、油菜、棉花、蔬菜、柑橘、猪、鱼的农业生产系统相比,在能值转化率、可更新率、能值投资率、能值自给率、净能值产出率、环境负载率、能值交换比率方面均表现出明显优势,并从能值的角度提出了完善循环农业体系的对策建议  相似文献   
286.
Agricultural management affects the movement of atrazine in soil and leaching to groundwater. The objective of this study was to determine atrazine adsorption in a soil after 20 years of atrazine application under agronomic management practices differing in tillage practice (conventional and zero tillage), residue management (with and without residue retention) and crop rotation (wheat-maize rotation and maize monoculture). Atrazine sorption was determined using batch and column experiments. In the batch experiment, the highest distribution coefficient Kd (1.1 L kg?1) at 0–10 cm soil depth was observed under zero tillage, crop rotation and residue retention (conservation agriculture). The key factor in adsorption was soil organic matter content and type. This was confirmed in the column experiment, in which the highest Kd values were observed in treatments with residue retention, under either zero or conventional tillage (0.81 and 0.68 L kg?1, respectively). Under zero tillage, the fact that there was no soil movement helped to increase the Kd. The increased soil organic matter content with conservation agriculture may be more important than preferential flow due to higher pore connectivity in the same system. The soil's capacity to adsorb 2-hydroxyatrazine (HA), an important atrazine metabolite, was more important than its capacity to adsorb atrazine, and was similar under all four management practices (Kd ranged from 30 to 40 L kg?1). The HA adsorption was attributed to the type and amount of clay in the soil, which is unaffected by agronomic management. Soils under conservation agriculture had higher atrazine retention potential than soils under conventional tillage, the system that predominates in the study area.  相似文献   
287.
This research aimed at assessing the properties of guinea pig manure digestate from low-cost tubular digesters for crops fertilization in rural Andean communities. To this end, field trials were carried out to evaluate the effect of the digestate on two common Andean crops: potato (Solanum tuberosum) and forage (Lolium multiflorum and Trifolium pratense L.). The potato yield (20-25 tha(-1)) increased by 27.5% with digestate, by 15.1% with pre-compost and by 10.3% with the mixture, compared to the control. The forage yield (20-21 tha(-1)) increased by 1.4% with digestate - 50% dose, and by 8.8% with digestate - 100% dose and digestate - 150% dose, compared to the control. The results suggest that the digestate is an appropriate substitute of manure pre-compost for potato fertilization. The results with forage indicate that it can be applied in a range of doses, according to the amount produced by the digester. Currently, manure is either used for cooking or as fertilizer. With low-cost tubular digesters implementation, it could be used to feed the digester, using the digestate for crops fertilization and biogas for cooking; improving household living conditions and protecting the environment. Since soil properties in rural Andean communities differ from experimental layouts, the effect of fertilizers should be re-evaluated in-situ in future research studies.  相似文献   
288.
基于环境因素的中国农业生产率增长研究   总被引:4,自引:0,他引:4  
考虑环境因素,运用方向性距离函数测算了1999-2008年中国30个省(直辖市、自治区)的农业环境技术效率,采用Malmquist-Luenberger生产率指数测度了28个省(直辖市、自治区)的农业全要素生产率(TFP)增长,并将其进一步分解为技术进步率指数和技术效率变化指数,以分析农业技术进步和农业技术效率变动对中国农业生产率增长的贡献.实证结果表明:东部的农业环境技术效率明显高于中、西部,而中、西部的差别很小,中部略低于西部;1999-2008年间各年的ML指数均值都大于1,表明中国农业每年的生产率都在增长;中国农业生产率的改进来源于技术进步,技术效率变化均值为0.997,农业技术效率在轻微退步;忽略环境因素会高估我国的农业生产率增长.在上述结论基础上,对如何促进中国农业生产率健康发展提出了相应的政策建议.  相似文献   
289.
波特假说主要从动态的角度论证了环境规制和农业科技进步之间的正向变亿关系.而在安徽省1990 -2008年的农业生产数据的基础上,选择合适的环境规制和农业科技进步的指标变量,运用Johansen协整分析方法验证了安徽省农业生产中的环境规制和农业科技进步的关系也符合这一假说,Granger因果关系检验说明了安徽省环境规制是农业科技进步产生的原因,脉冲响应分析和方差分析则更深入地从定量的角度分析了环境规制对农业科技进步影响滞后的趋势和影响程度.由实证分析可以看出,只是从静态角度来分析,环境规制是不利于农业的科技进步的;但从长期效益来看,环境规制有利于农业的科技进步.因此,在农业生态环境恶化的形势下,严格对农业废弃物的排放限制,制定较严格的农产品生产标准和产品质量标准,提高农民的环境意识和科技意识,通过强化环境规制来促使农业生产者提高农业生产技术,提高农产品品质和产品的市场竞争力就显得尤为重要.  相似文献   
290.
史小栋  操昌碧  朱永刚  尹嫚 《四川环境》2010,29(4):78-79,105
竣工验收是开发建设项目总结经验、提高认识、促进发展的重要环节。本文通过收集资料和现场查勘,提出水土保持竣工验收的具体内容和方法,对输电线建设项目水土保持设施竣工验收工作中遇到的问题进行了探讨。结果表明,输电线建设项目实际施工过程中存在一定的设计变更问题,水土保持措施实施情况与可研方案报告书中提出的水土保持措施有一定的差异,主要体现在植物措施和施工临时措施方面。  相似文献   
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