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241.
林场经营管理中需要坚持走科学发展的道路,发挥林场资源优势,提高林场经营管理的整体水平。当前林场经营管理中存在的基本问题是:林场性质定位不够明确、林场管理方式单一、林场经营管理中产权主体不够清晰、林场生产的产品结构单一等。需要在具体工作过程中发挥林场生产经营的自主权,采用多元化的经营模式,以提升整个林场的经济效益。 相似文献
242.
Oysters Isognomon alatus containing high concentrations of Zn, Cu, Pb and Cd were collected from the Sepang Besar River, and transferred to the Sepang Kecil River where the native oysters contain low metal concentrations. Concentrations of heavy metals in oysters were measured monthly over six months. The concentrations of all metals decreased significantly (p<0.05) for Cd 87%, Pb 83%, Cu 78%, and Zn 59%. In addition, metal depuration in oysters was investigated under laboratory conditions. Oysters were exposed to 100?µg?g?1 of metals for two weeks followed by one week of depuration. Our studies suggest that metals in oysters tend to be lost in the order, Cd>Pb>Cu>Zn. A comparison between laboratory and field data showed that depuration of metals under the laboratory conditions is significantly faster than in the field. 相似文献
243.
244.
Bernard Rollin 《Journal of Agricultural and Environmental Ethics》2001,14(1):29-37
The issue of regularly feeding low levels of antibiotics to farm animals in order to increase productivity is often portrayed as a dilemma. On the one hand, such antibiotic use is depicted as a necessary condition for producing cheap and plentiful food, such that were such use to stop, food prices would rise significantly and our ability to feed people in developing nations would decrease. On the other hand, such antibiotic use seems to breed antibiotic resistance into pathogens affecting human health. Resolving this dilemma, it is alleged, will require great amounts of research into risk/benefit assessment. Contrary to this claim, we will argue that society has all the data it needs to make a reasonable ethical decision, which would be curtailing such use. Such curtailment will not harm consumers significantly, will not harm developing nations' evolving agriculture, and could produce hitherto unnoticed benefits, namely restoring the possibility of a more husbandry-based, sustainable agriculture to replace the high-tech agriculture that has hurt animals, the environment, small farms, and sustainability. 相似文献
245.
Egon?NoeEmail author Niels?Halberg Jens?Reddersen 《Journal of Agricultural and Environmental Ethics》2005,18(4):383-414
Organic farming is expected to contribute to conserving national biodiversity on farms, especially remnant, old, and undisturbed small biotopes, forests, and permanent grassland. This objective cannot rely on the legislation of organic farming solely, and to succeed, farmers need to understand the goals behind it. A set of indicators with the purpose of facilitating dialogues between expert and farmer on wildlife quality has been developed and tested on eight organic farms. “Weed cover in cereal fields,” was used as an indicator of floral and faunal biodiversity in the cultivated land, and “uncultivated biotope area” on the farm was used as a general measure of wildlife habitats. Functional grouping of herbaceous plants (discriminating between “high conservation value” plant species and “competitive”/“ruderal” species) and low mobility butterflies were used as indicators of conservation value, especially focusing on the few sites left with considerable remnant conservation value. The dialog processes revealed that the organic farmers’ ideas and goals of conservation of wildlife quality were not necessarily the same as for biologists; the farmers expressed very different opinions on the biological rooted idea, that wildlife quality is related to the absence of agricultural impact. However, farmers also stated that the information given by the indicators and especially the dialogue with the biologist had influenced their perception and awareness of wildlife. We conclude that, combined with a dialogue process, using these indicators when mapping wildlife quality could be an important key component of a farm wildlife management advisory tool at farm level. 相似文献
246.
This paper reports on a nationwide survey of environmental farm plan programmes and plan characteristics, towards determining New Zealand's (NZ's) capability and eligibility for reporting on the Organisation for Economic Cooperation and Development's (OECD) environmental whole farm management plan agri-environmental indicator. Considerations regarding the validity of the indicator are discussed. Environmental farm planning in NZ is widespread, fragmented, and diverse. Nine of NZ's 16 regional authorities have environmental farm plan programmes involving 20 different types of environmental farm plans. Potentially half of NZ's total area of farmland is included, but this is reduced by limited and selective use of environmental farm plans as policy instruments. Three authorities are capable of readily reporting the number and coverage of their environmental farm plans; six would need to manually compile the information. Compliance monitoring is mostly informal, but necessary for checking the implementation of plan works and actions. Eligibility of NZ environmental farm plans cannot be determined until the OECD define acceptance standards. A contemporary definition of environmental farm plans is proposed, along with additional criteria necessary to ensure such plans are credible indicators of issue ownership, adoption of best management practice, and landscape changes intended to improve environmental quality. 相似文献
247.
生态农庄的规划设计与旅游开发研究——以江苏省无锡市唯琼生态农庄为例 总被引:2,自引:0,他引:2
对生态农庄的基本内涵、旅游资源以及规划的基本原理进行了阐述,并在此基础上总结出了生态农庄的一般规划程序。以江苏省无锡市唯琼生态农庄为例,具体探讨了生态农庄的功能定位和空间布局,尝试提出一种生态农庄的规划模式。 相似文献
248.
农户经营行为及其对生态环境的影响 总被引:4,自引:0,他引:4
20世纪70年代我国农村实行了家庭联产承包责任制,使农户成为了农业生产经营最基本单元,对农户经营行为的研究是解决“三农”问题的基础。农户不合理的经济活动与生态环境恶化有着直接的、必然的联系。从农户的经营行为动机出发,分析影响农户经济行为的主要因素及其对生态环境的影响已成为热点问题。农户经营行为与环境保护的矛盾主要表现在三个方面:(1)农户经营行为的短期性与环境影响的长期性;(2)农户经营行为的个体性与环境资源的共享性;(3)农户经营行为的针对性与环境政策的普适性。今后进一步研究的热点领域包括四个方面,其一是农户经营行为的政策影响机制研究;其二是对农户经营行为的环境影响过程的跟踪研究;其三是对农户经营行为环境影响的定量模拟研究;其四是探讨基于生态环境保护的农户经营行为最佳模式。改善生态环境的根本在于建立人类与自然界的和谐关系,使人们在追求经济效益的同时,考虑社会效益和生态环境效益。 相似文献
249.
本文采用对比分析的方法,分别对康集生态农场种植园、苗圃地和对照废窑地的主要小气候指标进行了观测分析。结果表明,农场种植园的建立有利于提高生长初期的日平均气温,增加干燥季节的空气相对湿度,明显降低各时期的地面最高温度和大风季节的风速,对农场局部小气候改善起了一定的作用。 相似文献
250.
通过大型规模化养殖场现场调研,按照清洁生产和循环经济发展模式,提出切实可行的生猪养殖场污染治理和废物资源化利用方案。 相似文献