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141.
Land exploitation, as an important strategy to mitigate farmland loss and stabilize grain production, has been adopted to compensate farmland loss due to rapid urbanization in China. Bounded by the limited capacity and obvious spatial variations of national farmland reserves, it is essential to arrange land exploitation activities timely and reasonably. In this study, we propose an indicator for the status of regional land exploitation, the Exploitation Degree, to facilitate an overview of land exploitation programs in China at both provincial and prefectural levels based on project data from 2006 to 2012. To further our understanding of the regional features of land exploitation activities, we employ the Lasso model to identify and quantitatively assess influencing factors on land exploitation. Our study shows that: (1) contemporary land exploitation practices in China are significantly inconsistent across exploitable farmland reserves. Some areas are greatly over-exploited and such irrational land exploitation has been persistent; (2) related national land plans designed to guide land exploitation efforts centered on resource-rich regions and critical areas do not function as intended. Therefore, we suggest that China⿿s land exploitation policy shall be improved by reconsidering the orientation of land exploitation policy, coordinating land exploitation activities with productivity improvements and eco-system protection, and enhancing the power and scope of the plans in controlling and guiding land resource management.  相似文献   
142.
Drawing on the resource-based view (RBV) of the firm this article examines relationships between knowledge, trust, communication, volatility and sustainable competitive advantage as the exogenous and endogenous variables with importer commitment as the dependent variable. The primary data was gathered from a survey of 224 commercial and industrial firms, headquartered in Bangladesh, coming from a wide cross section of industries. Statistical analysis was carried out using Structural Equation Modelling via AMOS. The study's key findings revealed that all exogenous/endogenous variables had a significant impact on importer commitment. That is, knowledge, trust, communication, volatility and sustainable competitive advantage had a significant direct impact on importer commitment. Additionally, cultural similarity, communication, volatility and supplier opportunism all had a significant indirect impact on importer commitment. This finding makes a significant contribution to the relational side of the RBV.  相似文献   
143.
基于1987-2017年中国省际面板数据,运用SYS-GMM模型研究异质型人力资本对经济增长的影响。在区分高级与基本人力资本基础上,基于招生率和收入维度,从全局和阶段差异视角剖析异质型人力资本对经济提速的机制演进。研究发现:全局而言,两种测度下基础和高级人力资本各自以数量及创新方式驱动经济增长,并呈现以数量驱动为主,数量、创新双驱动的增长模式;从演进视角看,两种测度均表明,高级人力资本创新驱动是新常态阶段经济增长的核心动力,但相比旧常态阶段,基础人力资本数量驱动日趋弱化并呈异质性;进一步研究表明,产业结构、城镇化及开放程度均对创新驱动有不同程度激励效应,而城镇化是挤出数量驱动的主要推手。  相似文献   
144.
以位于辽东湾北部的营口市和辽宁省内部的鞍山市为研究区,引用研究区土地利用图形数据,通过将景观斑块分类的方法,对辽东湾沿海及内陆城市的土地利用生态环境效应进行比较分析。结果表明:(1)辽东湾的优势景观为林地和旱地。(2)鞍山市的区域生态环境指数为0.43,营口市的区域生态环境指数为0.51。辽东湾沿海城市较内陆城市生态环境好。  相似文献   
145.
146.
An important determinant of informality in a country is its tax enforcement capacity, which some authors argue further distorts the decisions of firms and creates inefficiency. In this paper, I assess the quantitative effect of incomplete tax enforcement on aggregate output and productivity using a dynamic general equilibrium framework. I calibrate the model using data for Mexico, where the informal sector is large. I then investigate the effects of improving enforcement. I find that under complete enforcement, Mexico's labor productivity and output would be 19% higher under perfect competition and 34% higher under monopolistic competition. The source of this gain is the removal of the distortions induced by incomplete enforcement of taxes. These distortions affect the economy in three ways: by reducing the capital–labor ratios of informal establishments; by allowing low-productive entrepreneurs to enter; and by misallocating resources towards low-productive establishments. As a result, TFP and capital accumulation are reduced, and hence output. I decompose the gains following the guidelines of five leading papers in the literature of resource misallocation across plants. I isolate the effects of pure factor misallocation, distorted occupational choices, capital accumulation, and complementarities. I also study marginal improvements in enforcement and find that there is an inverted-U relationship between the size of the informal sector and output. This reflects the fact that improving enforcement entails a tradeoff: more taxes vs. fewer distortions.  相似文献   
147.
多丽丝·莱辛的处女作《野草在唱歌》不仅展现了男权社会中女性和其他弱势群体的生存状态,而且还饱含作者对自然与人类间关系的深刻思考。《野草在唱歌》是从角色的共性、地位的共性、生态女性主义的终极关怀这三个角度来体现生态女性主义的。  相似文献   
148.
上海依托其金融、贸易、航运的中心地位,吸引大量的跨国公司总部进驻。近10来年,上海的总部经济规模迅速扩大,形成几个特大规模的总部经济集聚区,但其总部经济的发展也存在较大的问题,总部集群的要素集聚度低,总部集群的创新水平低,总部集群创新环境较差等问题。建设好上海的总部经济有其重要的现实意义,我们应大力提高总部经济的自主创新能力、促进创新环境的建设、构建创新要素的网络结构等。  相似文献   
149.
技术转化为资本,资本创造价值已经成为共识,技术资本在不同公司创造价值的作用程度不同,根源是技术资本配置效率问题。选取沪深两市2008-2013年间制造业上市公司为样本,检验了基于不同股权性质的公司环境不确定性对企业技术资本配置效率和价值的影响,研究结果表明:①企业环境不确定性程度越高,技术资本配置效率越低,并且技术资本配置偏离度在国有公司中表现为配置过度,在非国有公司表现为配置不足;②在股权性质为国有的公司中,由环境不确定性引发的技术资本配置偏离将降低企业价值,在非国有控股公司中,由环境不确定性导致的技术资本配置偏离将增加企业价值。  相似文献   
150.
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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