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311.
This article proposes to use nutrient-orientated environmental efficiency (EE) measures to construct a nutrient total factor productivity index (NTFP). Since nutrient-orientated EE measures are consistent with the materials balance principle, NTFP index is superior to other existing TFP indexes. An empirical study on the environmental performance of an agricultural sector in 30 OECD countries from 1990 to 2003 yielded several important findings. First, these countries should be able to produce current outputs with at least 50% less aggregate eutrophying power, implying that they should have been able to substantially reduce the potential for eutrophication. Second, traditional TFP has grown by 1.6% per annum due to technical progress; however, there are lags in the responses of several countries to this technical progress. Third, environmental TFP has grown at a slower rate than traditional TFP growth due to reductions in nutrient-orientated allocative efficiency. Finally, changes in input combinations could have significantly improved environmental efficiency and productivity. These findings favor policy interventions and faster technological transfer to improve environmental performance.  相似文献   
312.
The acute-toxic-class method (ATC) is an alternative to the classical LD50 test. Four substances were tested with an ATC testing procedure. The results were compared with LD50 data obtained from the literature. Great importance was attached to the observations of toxic signs following administration. The results of this study have shown that the ATC method allows allocation to toxicity classes in the same manner as on the basis of the classical LD50 tests. The ATC method uses fewer animals and yields the same information on toxic signs. Introducing the ATC method into the quality system allows estimating the acute oral toxicity of chemicals according to the Organisation for Economic Cooperation and Development (OECD; OECD, 1992, 1996).  相似文献   
313.
Local Environment has established a bit of a niche in local sustainability indicator studies. In 1997 it published the important debate between Jeb Brugman and Graham Pinfield, which highlighted that sustainability indicators and their role are contested issues (Vol. 2, Nos 1-3). In 1999 it produce a first special issue on the topic (Vol. 4, No. 2). As the editors identified, this special issue probed ‘deeper into aspects of indicator selection, methodology, theory and practice’. The papers presented there began to discuss a theme that is developed further in this special issue, that of the relationship between the objective and the subjective in indicator development and use. Our special issue brings together three full papers and a commentary presenting research and information from the USA, Sweden, France and Austria. In this editorial we are going to review the growth of interest in sustainability indicators and the changing way in which they are viewed and briefly comment on some recent indicator projects that we have been involved in.  相似文献   
314.
This study examines sustainability indicators using the sustainability report of the Finnish Ministry of Agriculture and Forestry as the case study. The report is a compilation of indicators designed to assess the sustainability of natural resource management. The interviews with the users revealed, however, that the indicators have not been particularly effective in informing the actors or in affecting their behaviour. Clearly, the informative value of the indicators has been overrated and the complexity of the information transfer has been underestimated. At least partly, the difficulties were due to the obscurity of the indicator-concept itself and consequently to their improper use. First, the statistics with the objective state-of-affairs information should be distinguished from the indicators that are always related to policy discussion. In addition, the technical and communicative use of the indicators should be distinguished from each other as they have different relationship between the information, policy values and the associated activities.  相似文献   
315.
The Australian environment and agriculture is suffering from land degradation and declining biodiversity. Laws protecting native vegetation are aimed at addressing these problems but have been resisted by farmers, compromising the social agreement necessary for regulatory success. A case study drawing on farmer interviews in central northern New South Wales reveals that the laws are considered to be under-achieving environmental outcomes since they are ill-suited to local conditions. The low feasibility of the rules is also undermining rule and state legitimacy. Regulatory resistance is due to the lack of recognition of place-specifics by government and laws that impose universal requirements. There is an epistemic distance between the bureaucratic knowledge held by government and the vernacular knowledge (place-based knowledge) of heterogeneous environments held by farmers. Incorporating vernacular knowledge so that laws are more geographically sympathetic may close vernacular disjunctures and cure regulatory failure.  相似文献   
316.
全面分析了青藏高原东部藏族地区(简称藏东地区)农业资源特点及开发利用现状,阐明了农业资源开发利用中出现的生态环境问题及成因,提出了该地区农业资源合理开发,持续利用和生态环境保护的对策和措施。  相似文献   
317.
富营养浅水湖泊的退化与生态恢复   总被引:14,自引:2,他引:12  
初步讨论了富营养浅水湖泊的退化现象的造成退化的主要原因,对湖泊生态恢复的目标和对策等问题也作了探讨,以武汉东湖为例,提出以水源保护地为主要功能的富营养浅水胡泊的恢复和整体优化对策,即恢复沉水植被、建立控制面源污染的半自然的人工湿地生态系统,优化水产养殖结构和恢复湖泊生物多样性等。对生物操纵在长江中下游富营养浅水湖泊恢复中的作用也进行了讨论。  相似文献   
318.
介绍了四川省地形地貌、人口与农业资源概况,分析了四川发展农业循环经济的现状和模式,提出了四川发展农业循环经济的关键问题。  相似文献   
319.
以农业有机废弃物鲜猪粪、干稻草、青草、南瓜叶以及菜叶为原料,沼气产量和甲烷产量为指标,采用4因素3水平的正交实验设计方法对沼气发酵工艺参数优化配置进行了实验研究。结果表明反应器内原料碳氮比、原料固体浓度、反应环境温度以及投加微量元素对沼气发酵均有不同程度的影响,其中反应环境温度对沼气产量的影响显著。最优工艺条件为原料碳氮比25:1、固体浓度8%、温度35℃、投加微量元素Co。  相似文献   
320.
农业残留物燃烧温室气体排放清单研究:以江苏省为例   总被引:9,自引:2,他引:7  
刘丽华  蒋静艳  宗良纲 《环境科学》2011,32(5):1242-1248
通过问卷调查确定了江苏省农业残留物在不同时间阶段(1990~1995、1996~2000、2001~2005和2006~2008年)作为生活燃料和田间直接燃烧的比例,利用燃烧炉模拟秸秆燃烧试验确定了6种农业残留物(水稻、小麦、玉米、油菜、棉花和大豆)燃烧产生的CO2、CO、CH4和N2O的排放因子;基于此,结合江苏省不...  相似文献   
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