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851.
东北商品粮基地粮食生产的区域分异 总被引:32,自引:3,他引:29
论文以商品粮基地县为研究单元,运用数理统计和GIS空间分析结合的方法,揭示东北商品粮基地县粮食总产的区域差异。研究结果表明:①粮食总产低于平均水平的商品粮基地县占多数,高于平均水平的基地数量仅占36.36%,但粮食产量占全部基地县粮食总产量的64.74%;②粮食生产基本上形成了以玉米、大豆、水稻为主的生产能力格局,粮食总产的区域差异小于分品种粮食作物内部的区域差异;③从省域尺度看,粮食总产高于平均水平的基地县84.6%分布在黑龙江和吉林两省,粮食生产布局的区域化、专业化趋势明显,大宗粮食作物进一步向产粮大县集中;④从区域尺度看,粮食总产的空间格局高低交错,集中在以松嫩平原中部黑土区、辽河平原和三江平原为重心的平原地区,有由中部平原地区向周边递减的趋势。回归分析表明,播种面积的区域差异是导致商品粮基地县粮食总产区域分异的主要原因,农业现代化水平对其具有重要影响。应加强商品粮基地建设,加大中低产田的改造力度,走以提高粮食单产来提高粮食综合生产能力的内涵式发展道路。 相似文献
852.
以GC/ECD内标法定量测定了东海近岸泥质区、远岸济州岛西南泥质区和冲绳海槽共19个表层沉积物样中21种有机氯农药的含量.结果表明,有机氯农药在所有样品中均有检出,东海泥质区已有人类污染物的明显记录.研究区平均总有机氯农药分布特征为沿岸泥质区南部>沿岸泥质区北部>冲绳海槽>济州岛西南泥质区.冲绳海槽中HCHs含量高且其分布特征显著区别于陆架泥质区,显示该区域这一污染物源可能与陆架区有所不同.(DDD+DDE)/DDT比值显示东海泥质区DDT类农药的污染物还比较新.与国内其他地区沉积物中有机氯农药含量相比,东海泥质区有机氯农药污染属较低水平. 相似文献
853.
西部生态环境问题及对策建议 总被引:12,自引:1,他引:11
研究表明,西部地区生态环境问题主要表现在:①生态环境主要组成要素问题突出,表现在植被衰退、土地退化没有得到根本性控制,水环境问题突出,生态用水不能得到保障;②生态系统的生产功能、调节功能和生物多样性维持功能等服务功能下降;③生命支持系统受到威胁,生态破坏造成巨大经济损失,区域社会可持续发展支撑能力受到削弱.建议:西部地区应改变目前单要素、分割式的生态保护和建设思想,采取生态系统管理方式,树立预防为主、保护优先、防治结合的指导思想,加强重点生态功能区建设,开展区域生态保护研究,增加生态保护资金投入,建立生态补偿机制. 相似文献
854.
855.
Given the amounts of end-of-life electrical and electronic equipment (EoL-EEE) being generated and their contents of both harmful and valuable materials, the EoL-EEE issue should be regarded not only as an emerging environmental problem but also as a resource management strategy in China. At present, in order to provide the basis for managing EoL-EEE at both product and substance levels in China, it is necessary to carry out a quantitative analysis on EoL-EEE and to determine how much of it will be generated and how much materials and substances it contains. In this study, the possession and obsolescence amounts of five types of household appliance (HA) including television (TV) sets and the amounts of substances contained in EoL TV sets were estimated using time-series product flow analysis (PFA) and substance flow analysis (SFA). The results of PFA indicated that the total possession amounts of those five types of HAs will exceed 3.1 billion units in 2030, which will be two times higher than those in 2010. In addition, it was estimated that cumulatively over 4.8–5.1 billion units of these five types of EoL HA would be obsoleted between 2010–2030. The results of SFA on TV sets indicated that the generated amounts of most of the less common metals and a part of common metals such as copper (Cu) would tend to decrease, whereas those of other common metals such as iron (Fe) as well as precious metals would tend to increase in EoL TV sets in 2015–2030. The results of this study provide a quantitative basis for helping decision makers develop strategic policies for the management of EoL-EEE considering both environmental and resource aspects. Moreover, a calculation scheme of obsolete HAs presented in this study can be applied to estimate other types of EoL durable good. Meanwhile, the frameworks of this study will help not only the policy decision makers in the Chinese government but also those in developing countries that are facing similar problems. 相似文献
856.
基于大数据的视角对1993—2013年我国国家社科基金旅游项目进行了全样本统计和研究,并采用SPSS17.0软件对项目负责人、负责人所在单位、单位所在省市进行了描述性分析和聚类分析,同时借助ROSTCM6软件对项目主题进行了语义网络分析,全面展示了国家社科基金旅游项目反映的我国旅游发展格局,系统认识和评价国家社科基金旅游项目对我国旅游研究的贡献有一定的指导作用。 相似文献
857.
Rural sociologists and geographers have conceptualised different rural development trajectories including “the agri-industrial model”, “the post-productivist model” and “the rural development model”. Alternative food networks (AFNs) are increasingly recognised as a “forerunner” and a critical component of the emerging “rural development model” in the West. Meanwhile, Marsden and Franklin [2013. Replacing neoliberalism: theoretical implications of the rise of local food movements. Local Environment, 18 (5), 636–641] pointed out that there is a “local trap” in the current conceptualisation of AFNs that overemphasises their local embeddedness and heterogeneity. This “local trap” marginalises AFNs and, therefore, hinders their potential for transforming the industrialised conventional food system. The convergence and scaling-up of fragmented AFNs have been recognised as important ways to address this marginalisation issue and thus have attracted considerable attention. However, current studies of the convergence of AFNs focus mainly on the role of food-centred organisations without recognising the role of the emerging “rural development” initiatives in the convergence of AFNs. Based on in-depth interviews with key stakeholders and analysis of secondary data, this paper uses the New Rural Reconstruction Movement (NRRM), an emerging alternative rural development movement in China, as an example to illustrate how the NRRM opens up a novel space for the convergence of AFNs. We argue that the interrelationship between AFNs and rural development is indeed reciprocal. The NRRM, following the “rural development” trajectory, functions as a hub for the convergence and scaling-up of various alternative food initiatives. Strategies for achieving convergence include constructing a “common ground” for these initiatives, establishing national alliances and organisations, sharing knowledge and exchanging personnel among them. 相似文献
858.
简要统计了2015年1-2月国内发生的各种环境事件86起,包括沙尘天气7起,污染事件15起,地震46起,山体滑坡和泥石流6起,旱灾2起以及其他自然灾害10起. 相似文献
859.
This paper reviews the progress in climate change adaptation (CCA) policies both under the United Nations Framework Convention on Climate Change (UNFCCC) and in major regions and countries, including the EU and its major member countries, the influential developed countries in the Asia-Pacific region, the emerging economies and the least developed countries (LDCs). The progress made in China in CCA policies is also reviewed and compared with that in other countries. Finally, good international practices are proposed for China’s policy development. It is found that adaptation has been given the same priority as mitigation since the twenty-first century with regard to climate change-related actions. The topics related to adaptation in the international climate change negotiations under the UNFCCC have evolved from mechanisms for finance and technology development and transfer exclusively in the early stages to implementation of practical adaptation programs and actions. Since 2006, major developed and developing countries have frequently set forward specific CCA policies or general climate change policies involving adaptation in the form of laws, frameworks, strategies, and plans. The LDCs have also been working on National Adaptation Programmes of Action and subsequent National Adaptation Plans with the support from the financial mechanisms under the UNFCCC. Therefore, globally, it has become a common practice to develop national or regional policies to plan and guide CCA actions. China has established climate change policies involving adaptation at the national, regional, and sectorial levels since 2007. However, these policies have strong limitations in their knowledge base, strategic positioning, contents, and implementation mechanisms, e.g. lack of a sound knowledge base, an international perspective, clear responsibilities for policy implementation, and appropriate monitoring and evaluation mechanisms. It is recommended that China should further strengthen its technical capabilities in climate change projections as well as impact, vulnerability, and risk assessment, and develop methodologies and techniques for the preparation, impact assessment and implementation of CCA policies. Furthermore, future CCA strategies or plans should be developed with an emphasis on China’s vision and strategic position on the world stage. 相似文献
860.
Loss and damage (L&D) from climate change has threatened the sustainable development of humankind, while the progress of mitigative and adaptive measures carried out under the international multilateral framework has been slow. The scientific community and policymakers have placed increasing emphasis on the international L&D response mechanism as a potential direct solution. This paper reviewed the origins of such a mechanism, with an in-depth analysis of the related connotations. A review of the existing situation in China on work related to L&D arising from climate change was conducted, followed by a summary of the findings. Finally, measures and recommendations to improve China’s efforts were proposed in this issue. 相似文献