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91.
Douglas Gunnison John W. Barko 《Journal of the American Water Resources Association》1989,25(1):193-201
ABSTRACT: This article, based on a review of the literature, examines several aspects of the rhizosphere ecology of submersed macrophytes. These include the role of the rhizosphere microflora in affecting plant growth through influences on nutrient availability and production of plant growth regulating compounds. Interactions between components of the sediment microflora and plant roots are considered in relation to plant nitrition and growth. Possible applications of this information to the management of submersed macrophytes are considered. 相似文献
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江苏沿海滩涂开发现状分析 总被引:6,自引:0,他引:6
本文作者根据多年的江苏滩涂开发利用调查资料,着重分析了江苏滩涂开发成就,开发潜力和制约因素三方面的现状,提出了加快滩涂开发的重要措施。 相似文献
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双流区域地下水污染现状及评价 总被引:1,自引:0,他引:1
本文在双流区域地下水污染调查基础之上,选用了主要反映工业生活污染的综合指标COD、BOD5和反映农业污染程度的NH3-N,NO3-N,NO2-N作为评价因子,研究了双流地下水污染现状,采用了综合指数法和点群分析法分类并评价了区域地下水污染对饮用水源地的影响程度。 相似文献
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Mozammel Mridha 《Local Environment》2020,25(8):540-558
ABSTRACT Residential satisfaction is a vital component of individual quality of life which has been explored by researchers from different perspectives. This study takes the stance to investigate residential satisfaction from sociodemographic standpoints. The purpose is to contribute to further research on residential satisfaction by exploring specifically the impact of age, gender and marital status on overall residential satisfaction and in more detail with components of residential satisfaction of residents living in apartment buildings in Dhaka, Bangladesh. Quantitative analyses of a survey of 204 residents living 59 apartment buildings in Dhaka was conducted to examine whether there is any relation between residential satisfaction with age, gender and marital status of the apartment dwellers. This study also examined if these sociodemographic characteristics had a moderator effect on some of the key components of residential satisfaction. Primary findings indicate that there exists a significant relationship between residential satisfaction with age, gender, and marital status. Further analysis revealed that the “Married” group was more satisfied than the “Single/Never married” group, senior people tend to be more satisfied than are younger respondents and females were more satisfied than males concerning overall residential satisfaction. This study concludes that potential sociodemographic differences among households in apartment developments in Dhaka should be considered for effective residential satisfaction and to create a socially sustainable living environment. 相似文献
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This article examines the recent revision of the Sphere Minimum Standards in disaster response relating to food security, nutrition and food aid. It describes how the revision attempted to incorporate the principles of the Humanitarian Charter, as well as relevant human rights principles and values into the Sphere Minimum Standards. The initial aim of the revision was to ensure that the Sphere Minimum Standards better reflected the principles embodied in the Humanitarian Charter. This was later broadened to ensure that key legal standards and principles from human rights and humanitarian law were considered and also incorporated, in part to fill the "protection gap" within the existing standards. In relation to the food security, nutrition and food aid standards, it was agreed by participants in the process that the human right to adequate food and freedom from hunger should be incorporated. In relation to more general principles underlying the Humanitarian Charter, itself drawn largely from human rights and humanitarian law, it was agreed that there was a need to strengthen "protection" elements within the standards and a need to incorporate the basic principles of the right to life with dignity, non-discrimination, impartiality and participation, as well as to explore the relevance of the concept of the progressive realisation of the right to food. The questions raised in linking rights to operational standards required thought, on the one hand, about whether the technical standards reflected a deep understanding of the values expressed within the legal instruments, and whether the existing standards were adequate in relation to those legal rights. On the other hand, it also required reflection on how operational standards like Sphere could give concrete content to human rights, such as the right to food and the right to be free from hunger. However, there remain challenges in examining what a rights-based approach will mean in terms of the role of humanitarian agencies as duty-bearers of rights, given that the primary responsibility rests with state governments. It will also require reflection on the modes and mechanisms of accountability that are brought to bear in ensuring the implementation of the Minimum Standards. 相似文献
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从气候、淡水资源和海洋资源等方面简要介绍了山东省的水产资源自然条件,概述了主要淡水虾和海水虾的资源及其分布。从养殖规模和养殖模式两方面总结了主要经济虾类的养殖现状,指出了优质虾苗繁殖困难、病害防治水平低、产品质量差、销售渠道狭窄等制约虾类养殖业发展的主要问题,并据此提出了相应的对策。 相似文献