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881.
发展有机农业 控制农业污染 总被引:1,自引:0,他引:1
有机农业(organicfarming)是指在动植物生产过程中不使用化学合成的农药、化肥、生产调节剂、饲料添加剂等物质,以及基因工程生物及其产物的一种农业生产方式。有机农业产生于上世纪30年代,其发展历程分为产生、扩展和增长3个阶段。中国的有机农业兴起于20世纪80年代,是在生态农业的基础上发展起来的。黑龙江省于1995年开始发展有机农业,实施有机产品开发,目前有机产业已成为黑龙江省的第6大产业。本文论述了发展有机产业对控制农业污染的意义,以及黑龙江省有机农业、有机产业发展现状和存在的问题,并对其发展提出了对策建议。 相似文献
882.
稻田综合种养土地利用的生态—经济效果——以湖北省稻虾共作为例 总被引:1,自引:0,他引:1
关注以稻虾共作为代表的稻田综合种养土地利用新型模式,基于在湖北省潜江市和荆州市的实地调研数据,运用非期望产出的SBM模型和投入导向DEA方法,测算和比较了稻虾共作户和水稻单作户土地利用的生态—经济效果。研究发现:与水稻单作相比,稻虾共作能够改善土地利用的生态—经济效果;但调研区一半以上的共作农户仍然延续着传统粗放的生产模式,生产中存在严重的过量投入,阻碍了其土地利用生态—经济效果的进一步优化。此外,若忽略环境污染,只考虑经济效果,将导致稻虾共作的土地利用效率被高估45.28%。目前,稻虾共作提高土地利用效率的功能未能充分发挥,亟需把环境影响纳入土地利用效率评估中,贯彻“双水双绿”的发展理念,引导农户合理安排各项生产投入,切实优化稻虾共作的生态—经济效果,促进土地可持续利用。 相似文献
883.
884.
Material selection in manufacturing may be characterized as a series of trade-offs between characteristics, properties, environmental impacts, sustainability, availability, and economics. Societal concerns about the environmental impacts of construction practices and materials have been expressed through an increase in the demand, production and use of “green” building products. This, combined with a desire to integrate more bioproducts and natural and renewable resources into the construction industry, has extended to the production and promotion of insulation made from sheep's wool.Although substantial literature exists on the insulation properties and other benefits of wool, less is known about the economics and manufacturing processes of sheep's wool insulation at varying scales of production. This paper contributes to this field of enquiry through presentation of the preliminary results of a wool insulation manufacturing pilot project, in which the scale and economics of the production of sheep's wool insulation were considered. Processing techniques, the impact of sheep breed, yield, energy use, and manufacturing costs were also examined. The results of the pilot project indicate that, while sheep's wool insulation produced at a smaller, or artisanal scale shows some potential, scale of operation and volume of production need to be carefully considered in order to ensure long-term sustainability of the operation. Using the least expensive sheep's wool available for the manufacture of wool batt insulation (and thereby reducing production costs) did not, in this pilot study, have a negative impact on productivity or product performance. Diversion of this waste stream of currently less marketable, and consequently less valuable wool, into the production of a green building material may offer small but significant benefit to sheep producers and the broader agricultural community, as well as consumers. 相似文献
885.
Myanmar's water‐related sectors are subject to intensive changes, as the country's abundant land and water resources provide substantial scope for development. Recent steps towards economic reform in Myanmar have led to a surge of foreign investment directed towards intensified natural resource extraction. Both the agricultural and the energy sector are increasingly affected by foreign investments that will impact the status of water, energy and food security in the country. With these on‐going developments, Myanmar's future is largely dependent on how its natural resources are managed and how the benefits from the resource extraction are shared. With various institutional changes and new actors welcomed to the sectors, existing livelihoods and ecosystems dependent on the land and water resources are to face increasing competition for the shared resources, while lacking secured access to them. There are increasing concerns that this sectoral development is occurring at the expense of environmental and social sustainability. As one way to tackle these challenges, the water‐energy‐food nexus approach could help in finding synergies and co‐benefits across sectors by addressing the imbalances along the nexus and externalities derived from the on‐going intensification. 相似文献
886.
实施农业清洁生产势在必行 总被引:8,自引:0,他引:8
从农业生产及农业污染的特点入手,借鉴工业清洁生产的基本理念,初步界定了农业清洁生产的内涵。从农业可持续发展战略的高度,论述了实施农业清洁生产战略的必要性和可能性,并就全面推行农业清洁生产战略提出建议。 相似文献
887.
Leslie Gray Patricia Guzman Kathryn Michelle Glowa Ann G. Drevno 《Local Environment》2014,19(2):187-203
Urban policymakers and sustainable food activists have identified urban agriculture as an important strategy for confronting a host of urban problems, including food insecurity, health disparities, access to urban green space and community economic revitalisation. Much recent work on urban agriculture has examined community and school gardens, but little research has been undertaken on home gardens as a solution to urban problems. This article examines a home-gardening programme in San Jose, California, La Mesa Verde, asking whether some of the benefits found in community gardens can be found in home gardens. Specifically, we look at financial, health and community benefits, examining the potential of home gardens to become forces for broader social change. We ask whether gardens can become agents of cultural preservation, self-determination, particularly for recent immigrants who use these spaces to build identities and work towards collective action and self-determination. 相似文献
888.
R. Peter Richards Ibrahim Alameddine J. David Allan David B. Baker Nathan S. Bosch Remegio Confesor Joseph V. DePinto David M. Dolan Jeffrey M. Reutter Donald Scavia 《Journal of the American Water Resources Association》2013,49(3):715-724
Richards, R. Peter, Ibrahim Alameddine, J. David Allan, David B. Baker, Nathan S. Bosch, Remegio Confesor, Joseph V. DePinto, David M. Dolan, Jeffrey M. Reutter, and Donald Scavia, 2012. Discussion –“Nutrient Inputs to the Laurentian Great Lakes by Source and Watershed Estimated Using SPARROW Watershed Models” by Dale M. Robertson and David A. Saad. Journal of the American Water Resources Association (JAWRA) 1‐10. DOI: 10.1111/jawr.12006 Abstract: Results from the Upper Midwest Major River Basin (MRB3) SPARROW model and underlying Fluxmaster load estimates were compared with detailed data available in the Lake Erie and Ohio River watersheds. Fluxmaster and SPARROW estimates of tributary loads tend to be biased low for total phosphorus and high for total nitrogen. These and other limitations of the application led to an overestimation of the relative contribution of point sources vs. nonpoint sources of phosphorus to eutrophication conditions in Lake Erie, when compared with direct estimates for data‐rich Ohio tributaries. These limitations include the use of a decade‐old reference point (2002), lack of modeling of dissolved phosphorus, lack of inclusion of inputs from the Canadian Lake Erie watersheds and from Lake Huron, and the choice to summarize results for the entire United States Lake Erie watershed, as opposed to the key Western and Central Basin watersheds that drive Lake Erie’s eutrophication processes. Although the MRB3 SPARROW model helps to meet a critical need by modeling unmonitored watersheds and ranking rivers by their estimated relative contributions, we recommend caution in use of the MRB3 SPARRROW model for Lake Erie management, and argue that the management of agricultural nonpoint sources should continue to be the primary focus for the Western and Central Basins of Lake Erie. 相似文献
889.
Nina Nevala-Puranen Lars Sörensen 《International journal of occupational safety and ergonomics》2013,19(1-2):77-88
In agriculture, occupational injuries are common, and several of them lead to permanent physical disability. The objective of this case study was to assess the strain and the ergonomic needs of four farmers (aged 34–49 years) with physical disabilities. A maximal bicycle ergometer test or an arm-crank test was done to assess their maximal heart rate (HR max) and maximal oxygen consumption (V02max). The strain at work was analyzed by measuring heart rate (HR), muscle activity (EMG), and the rating of perceived exertion (RPE). The farmers were interviewed as to possible and impossible work tasks and the ergonomic redesign measures taken to improve the work environment. The work tasks performed were mainly light or moderate work for the cardiorespiratory system according to mean HR (88-102 beats/min), the percentage of HR range (17–31% HRR), and the relative V02 (22–46% V02max). The mean activity of the trapezius muscles was 0.4-9% of the maximal voluntary contraction (%MVC). All the participants had work tasks they were unable to perform. They had made ergonomie redesign changes mainly to the tractor. This case study showed that some agricultural work tasks were possible for farmers with physical disabilities and that the physical strain associated with these tasks was mainly light or moderate. 相似文献
890.
农户兼业行为演化的实质是由家庭成员个体就业行为决策和家庭集体劳动分工决策共同决定的,而人力资本通过影响非农就业对农户兼业决策具有内生作用,但这种作用机制既包括农民个体层面,更涉及农户整体层面。基于家庭整体视角分析了农户人力资本的理论特性,提出了农户人力资本对家庭兼业行为及其离农决策存在双重影响效应的研究假设,在此基础上,运用长三角地区1036户农户调研数据进行了实证研究。结果表明,农户劳动成员平均人力资本数量水平提升和成员间人力资本结构差距缩小,对提升农户非农化兼业程度以及增强其主动离农意愿具有积极意义,其中农户人力资本结构效应对农户离农决策更为显著;进一步比较发现,教育和迁移人力资本对长三角兼业农户的非农化发展和离农意愿具有显著促进作用,而受不同因素影响,健康和以非农工龄为衡量的技能人力资本的作用效应总体却并不明显。文章认为,要把促进兼业农户人力资本发展作为推动其非农兼业升级与离农决策的立足之本,在当前农地征用补偿政策思路上,要从单纯重视对失地农户短期"经济补偿",向扶持家庭成员人力资本投资以增强其长期非农就业发展之"能力补偿"转变,进而构筑可持续生计保障。 相似文献