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Land greening in China is regarded as contributing a great deal to greening of the Earth. The phenomenon is mainly attributed to climate change, arising atmospheric CO2 and ‘Grain for Green’ (GFG) land management policies. However, limited knowledge is known how much land greening is from contributions of the GFG practice. Therefore, the study took the typical region of the GFG practice, the Loess Plateau, as the study area, and used 1982–2015 satellite-observed GIMMS3g normalized difference vegetation index (NDVI) data, ERA-Interim climatic variables (precipitation, temperature and solar radiation) and atmospheric CO2 concentration data with the help of a developed TPRC-based NDVI model to derive GFG-induced NDVI after 1999. Furthermore, this study tracked the spatial-temporal dynamics of GFG-induced NDVI and assessed contributions of the GFG practice to regional vegetation changes. Results showed that satellite-observed NDVI and TPRC-based NDVI both exhibited an increasing spatial pattern from the northwestern to southeastern Loess Plateau, but their greening trends were separately 0.0022 and 0.0009 per year in 1982–2015 (p < 0.05). Note that the satellite-observed greening trend was much steeper with a slope of 0.0056 per year after 2006 (p < 0.05). The subsequent analyses documented that GFG-induced land greening were largely responsible for the steep trend. In space, evident greening patterns began to be observed in the central Loess Plateau from 2006 to 2008, afterwards expanded towards eastern and southwestern Loess Plateau. In 2011–2015, the increase magnitude of GFG-induced land greening in the Loess Plateau averagely accounted for 8.5 % in comparison to estimated TPRC-based NDVI, but in six natural zones were various, ranging from 3.2%–15.7%. In some regions of central Loess Plateau, GFG-induced NDVI contributed even more than 20 % to vegetation increase. This study highlights that land use management contributes more to land greening dynamics over the Loess Plateau compared to climate change and arising atmospheric CO2 concentration. These findings likely provide some valuable information for curbing or enhancing specific-location vegetation changes in future regional land management and planning. 相似文献
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明洪武到弘治年间,州县官府的赋役管理从基本不依赖核算向需要且能够进行核算的状态转变。洪武、永乐时期,在官府体系内部,只有田赋被部分地纳入核算管理,其他赋役征发则完全或绝大部分无法计量,也没有计划性。宣德以降,地方官员吸收民间粮里阶层分担赋役负担的经验,在此基础上进行旨在“均平”的改革,以确保赋役的可持续征发。在探索均平之道的过程中,不同地方官员多采取量化赋役负担、预定征收计划、将派征对象标准化并进行摊派核算的方式。其中,田赋额等开始扮演摊派对象的角色。这开启了州县层面赋役征收核算体系的发展之路,也导致府、州、县与户、工等部及布政使司之间产生了赋役核算信息不对称,出现了二重会计结构。 相似文献
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白灵菇是我国具有自主知识产权和明确原产地的品种,以独特的风味、细嫩的质感、丰富的营养以及保健功能受到大众喜爱,栽培规模越来越大。该文对白灵菇产业发展现状、市场前景和存在的问题进行了阐述和分析,并提出了白灵菇产业持续、健康、快速发展的对策。 相似文献
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本文在开放系统中研究了广西区位优势系统演化,通过分析该系统演化的状态、系统的突变性和同步性演化特征,认为广西区位比势系统呈现出以资源流转型为主的与系统环境相对应的同步性特征,要实现向资源流转型和信息服务型相结合的系统转变,必须依靠企业家的创新,政府应通过相关政策和措施使系统潜能成为企业家可利用的公共“基因库”,以利于提高企业家储存“通类”信息能力,加强信息交流和相互学习,加大系统的非线性作用,使系统突变性演化成为现实。 相似文献
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史利平 《全球科技经济瞭望》2013,(8)
2013年,法国新政府在教育和科研领域将逐步推进各项改革,其教研部拟推进的主要措施有:取消“盖昂通函”,推行决策会商工作机制,实施超级联合大学计划,颁布新高等教育和科研法,确定未来科研优先领域,强化对欧盟科研影响力和加强科研人才队伍建设等。法国政府希望通过采取以上措施,继续保持法国的世界科技强国地位和优势。 相似文献
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商业银行开展金融租赁业务的建议 总被引:1,自引:0,他引:1
金融租赁具有融物与融资双重功能,与其他传统的融资方式比较而言,以金融租赁方式进行融资在功能上具有明显的优势,发展的前景非常广阔。本文就银行开展金融租赁业务提出相应对策建议。 相似文献
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新时期土地利用规划修编的理论与方法及实施制度创新的研究 总被引:7,自引:3,他引:4
利用文献资料分析法,在分析我国土地利用规划所面临的形势和总结了1997—2010年轮次土地利用规划决策实施存在问题的基础上,提出了土地利用规划理论、方法和实施制度创新的设想,指出规划需要树立以人为本的理念、目标有限性理念和刚性与弹性规划结合等理念,注重绿色规划;规划分区应在建立新的土地分类基础上,按照土地利用规划控制方向的一致性划分土地利用区,以适用规划管理的要求;注重规划编制修改制度的规范化,提出了规划实施制度创新的设想。 相似文献
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