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1.
Selenium like any other element can both be essential and toxic depending upon the concentration at which it occurs in human diet. This paper assessed the level of this trace element in twenty different (20) types of locally produced food items around Abeokuta town and the blood obtained from the antecubital fossa vein of eighty-eight (88) healthy adults resident in Abeokuta.  相似文献   
2.
Abstract. The stomach contents of poor cod, Trisopterus minutus capelanus (Lacepède), were taken at monthly intervals off the eastern coast of the Gulf of Valencia (Spain). A total of 1276 were analyzed to determine diet according to fish size and season. The basic food consists of crustaceans (Mysidacea and Decapoda) and teleosts. Feeding habits varied with size: decapods and fishes were more abundant in the stomachs of larger specimens. Little seasonal variation in food habits was recorded.  相似文献   
3.
Despite rapid economic growth, India has not seen the improvements in food and nutritional security that other developing countries have had. This “Asian enigma” has generated a wealth of economistic analyses seeking to explain the persistence of poor nutrition, yet few studies have looked at everyday experiences of changing food systems, and how this impacts nutritional practices as well as the processes of subject formation. In this paper, I draw on qualitative research conducted in Uttarakhand, North India and examine how state-led shifts in agricultural production have resulted in changing food consumption practices and diminished perceptions of health. Villagers link this decreased health to increased chemicals in home-produced food, greater dependence on the market for food purchases, and generational changes in dietary preferences. Despite villagers’ cognizance of the negative health effects of these practices, they largely view these byproducts of capitalistic development with an air of inevitability. Following Mansfield (2011) this paper contributes to the political ecology of health literature by employing the concept of food as a “vector of intercorporeality” (Stassart and Whatmore, 2003:449) and bringing this into conversation with a poststructuralist understanding of subjectivity. I argue that within shifting landscapes of agriculture production and food consumption, notions of diminished health are indicative of the complex and always incomplete processes of subject formation. I view shifting health perceptions as intimate bodily resistances to agricultural development, and conclude that within agricultural development programs a focus on bodily health and well-being is a fecund platform for further experimental research that seeks to imagine development differently.  相似文献   
4.
本文首先列举了近几年发生的几起典型的境外组织、机构和人员对我国进行的非法测绘案件,分析了空间数据的重要性以及公众对空间数据安全的认识误区,提出了制定我国空间数据安全政策的建议。  相似文献   
5.
内蒙古生态承载力评价及生态安全格局优化   总被引:2,自引:0,他引:2  
冯琰玮  甄江红  马晨阳 《地理研究》2021,40(4):1096-1110
生态安全水平对区域发展的约束作用不断增强,构建科学合理的生态安全格局可以有效缓解经济发展与环境保护之间的矛盾.以内蒙古自治区为研究区,2000年、2005年、2010年、2015年为间断点,建立区域生态承载力评价指标体系,探讨生态承载力时空演变特征;甄别生态优势斑块,结合自然保护区等重要生态斑块组建生态源地,建立生态源...  相似文献   
6.
This paper offers a systematic analysis of the concepts and contexts that frame the climate-smart agriculture (CSA) discourse in the academic and policy literature. Documents (n?=?113) related to CSA and published in peer-reviewed journals, books, working papers, and scientific reports from 2004 to 2016 were reviewed. Three key trends emerged from the analysis: studies are biased towards global policy agendas; research focuses on scientific and technical issues; and the integration of mitigation, adaptation, and food security (the three pillars of CSA) is becoming a popular scholarly solution. Findings suggest that CSA is a fairly new concept used to describe a range of adaptation and mitigation practices without a specific set of criteria. Although CSA is often framed around the three pillars, the underlying issues constructing the discourse differ at global, developing, and developed country scales. Although there is increasing research on developing countries, particularly in relation to how CSA can transform smallholder agriculture, there is a paucity of research documenting the experiences from developed countries. The findings suggest that research on CSA needs to move beyond solely focussing on scientific approaches and only in certain geographical contexts. If CSA is to be applicable for farmers across the globe, then cross-disciplinary research that is underpinned by broad socio-economic and political contexts is essential to understand how differences in narratives might affect implementation on-the-ground in both developing and developed countries.

POLICY RELEVANCE

Although policy makers are increasingly supportive of the climate-smart agriculture (CSA) approach, the rhetoric has largely been developed on the basis of scientific and technical arguments. The political implications of varying perspectives have resulted in a growing divide between how developing and developed countries frame solutions to the impacts of climate change on agriculture under the 2015 Paris Agreement. Different framings are part of the explanation for why the scope of CSA is being rethought, with the scientific community redirecting attention to seeking a separate work programme under the United Nations Framework Convention on Climate Change (UNFCCC). The current policy framing of CSA will give no new policy direction unless it grounds itself in the smallholder farmer and civil society contexts.  相似文献   
7.
试论生态旅游的生态化道路--以自然生态旅游区为例   总被引:5,自引:1,他引:5  
生态旅游已成为当今世界旅游发展的潮流。然而,在生态旅游开发过程中,存在着众多的。非生态化”现象,尤其是在自然生态旅游区。分析当前自然生态旅游区旅游开发和建设中的“非生态化”现象,主要包括盲目开发,自然景观破坏严重;游客严重超载,生态环境受破坏;人造景观和设施泛滥,景观污染和趋同现象严重;管理和文明建设落后,文化景观功能退化或受损等。运用景观生态学原理和生态安全理论等,从景观功能分区、旅游生态管理容量、景观结构生态设计、景观生态安全格局构建、生态教育等方面提出自然生态旅游区的生态化道路。  相似文献   
8.
河湖水系连通是中国正在推进的重大治水战略,是提高国家水资源统筹调配能力、水生态环境修复能力和河湖健康保障能力的重大举措,也是提高水旱灾害抵御能力的重要保障.目前河湖水系连通的知识比较零散,尚未形成系统的理论体系,河湖水系连通理论基础的研究,对理论体系的构建、战略的实施和持续推进具有重要意义.本文基于河湖水系连通的理论研...  相似文献   
9.
简要介绍了电子地图及导航电子地图的概念、特点、用途,借鉴当今和历史事例说明两者对国家安全的重要性,进一步论述如何加强对导航电子地图的管理,建议通过宣传教育以提高人们的国家安全意识。  相似文献   
10.
张鹏  丘萍 《中国岩溶》2014,33(4):483-489
岩溶地区拥有丰富的旅游资源,但是生态环境相对脆弱,根据岩溶地区旅游发展的特点,以"压力-状态-响应"(PSR)模型为基础,同时从生态安全的概念出发,涵盖生态风险、生态健康和生态足迹指标,建立了岩溶地区旅游生态安全评价指标体系。调整的主要指标包括:土地压力指标、旅游经济密度、年平均气温和年平均降雨量指标、旅游空间密度、游客密度指数、旅游收入指标等。采用综合指数法和熵权法,分别引入2012年和2007年两年的数据,对广西岩溶地区旅游生态安全的现状、发展趋势及变化趋势的内在原因进行了分析。实证结果表明:(1)从现状评价看,2007、2012年广西岩溶地区旅游生态安全水平总体较低,处于安全级别的城市主要位于广西中部区域,其他城市则处于不安全级别;(2)从影响指标看,经济状态和旅游生态状态对当地的旅游生态安全影响较大;(3)从变化趋势看,广西岩溶地区旅游生态安全状态逐渐好转,广西中部地区保持安全状态,紧邻广西中部地区的地市处于持续危险区域,但综合指数呈上升趋势;梧州和贵港两个位于广西东部的城市同样处于持续危险区域,但是旅游生态安全综合指数呈小幅下降趋势;(4)旅游生态安全状态和趋势与岩溶分布没有显著的相关关系。   相似文献   
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