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[目的]粮食安全的根本是在耕地,关键在于耕地质量。目前新增耕地主要源于土地开发项目、城乡建设用地增减挂钩土地复垦项目等,这些新增耕地需要对其开展耕地质量等别评定工作,了解新增耕地的质量状况,分析其空间特征,这对落实国家耕地保护制度、开展农村土地整治工作等具有重要作用。[方法]文章以南方典型丘陵区域——江西省宜春市作为研究区域,在新增耕地质量评价的基础上,运用地统计学、景观生态学、Arcgis空间分析技术和典型相关分析方法,研究宜春市新增耕地质量的空间特征,掌握耕地质量等别的分布规律,了解耕地质量的影响因素,为制定合理的耕地资源利用与保护政策提供依据。[结果](1)Moran′s I值结果表明宜春市2014年新增耕地利用质量在空间分布上的空间自相关性最强,而耕地自然质量空间自相关性最弱。(2)景观破碎度指数结果表明优、高等别的新增耕地质量破碎度大于中、低等别的; 多样性指数结果表明新增耕地质量多样性指数比较大; 优势度指数结果表明新增耕地质量等别优势度指数比较小,与多样性指数结果相呼应; 均匀度指数结果表明,新增耕地质量等别均匀度指数相差不大,新增耕地质量等别比较均匀。(3)质心结果表明2013—2014年间宜春市新增耕地质量的格局整体上是向西南方向变化。[结论]宜春市新增耕地质量不高; 新增耕地的利用水平差异性较小,自然本底状况差异较大; 新增耕地质量等别类型多,各质量等别类型耕地均有增加,耕地质量参差不齐,较高等地的新增耕地相对低等地而言更破碎化; 新增耕地的开发格局向着西南方向移动; 该研究为南方丘陵区的新增耕地保护提供了一定的参考依据。  相似文献   
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随着产业链与供应链的深入与完善,以品牌认同为引领的价值创造再一次引起关注,基于"生产商-经销商-终端商"三位一体的价值共创思维是重塑品牌形象强化品牌认同的关键.研究认为:经销商层面中人口基数、人均可支配收入、配送能力等是实现价值增值的因素,生产商层面中市场费用支持、分销政策支持、品牌战略提升是促进价值提升的关键,终端商层面中客情维护、货龄管理、品牌维护是保障价值实现的途径.  相似文献   
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Family firms bear two types of agency costs, including type I and type II agency problems, in corporate environmental practices: (1) Outside executives at family firms hesitate to engage in environmental strategies, which can lead to drops in profits; (2) Controlling families employ opportunistically environmental management to achieve their interests. We argue that a primary cause for the agency problems lies on ineffective internal corporate governance at family firms, which can cause loss of managerial (or power) balance between outside executives and family executives. Our findings show that family firms with ownership and strategic control (FSC), which family executives and outside executives monitor and constrain each other, can achieve the highest environmental performance. Moreover, external controls, including product market competition and provincial environmental regulations, substitute effective internal control of FSC. The environmental performance premium of FSC is more prevalent when the production market competition is lower. Family firms with ownership, operational, and strategic control (FOSC) can achieve higher environmental performance within a province with more stringent environmental regulations.  相似文献   
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Haze pollution has become a new threat to China's sustainable development, but it may be that local government behaviour can play an important role in the prevention and control of pollutants. A dynamic spatial autoregressive (SAR) model is used to study the relationship between local government competition and haze pollution. To further explore the indirect impact of factor market distortion on haze pollution and control potential endogeneity problems, a newly developed intermediary effect model that incorporates the characteristics of the generalized method of moments (GMM) is utilized to explore how factor market distortion indirectly affects haze pollution. The research results show that regional haze pollution in China is characterized by significant spatial correlation, and local government competition has a positive impact on haze pollution; that is, local government competition exacerbates haze pollution. In general, local government competition not only directly leads to an increase in haze pollution but also further intensifies it by distorting the local factor market, and the intermediary role of factor market distortion is approximately 7.04%. The results of the regional inspection found that competition among local governments in the eastern region did not lead to haze pollution, and distortion of the factor market did not exist as an intermediary effect. However, both direct and intermediary effects are significant in the central and western regions. Therefore, an official performance appraisal system that includes ecological constraints should be established to guide the benign transformation of local government competition, and an environmental management mechanism must be developed for joint prevention and control to reduce haze pollution. In addition, the free flow of factors and marketization are equally important.  相似文献   
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This is the first study to document evidence of technical trading effectiveness at firm level in the Chinese A-share market by investigating the relationship between excess profits of technical trading rules and firm-specific characteristics. Our results reveal that firms with higher excess profits from technical trading have more noise traders and higher institutional ownership and that those firms tend to be growth firms with lower liquidity and higher firm-specific uncertainty. Further analysis shows that the profitability of technical trading rules is unsustainable and the excess profits of the highest technical trading profit quintile portfolio disappear in the following year.  相似文献   
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The Grand Anse Declaration of 1989 recognised the need for financial integration within the emerging economies that comprise the CARICOM region, as a way of furthering the wider process of economic integration and, indeed, economic development in that region. Using co-movement as a measure of financial integration, this paper investigates the co-movement in stock prices among the Barbados, the Jamaica and the Trinidad and Tobago Stock Exchanges, the three major exchanges within the CARICOM region. It also examines how integrated these exchanges are with the New York Stock Exchange. The GARCH-Copula methodology and, to a lesser extent, estimated correlation coefficients, are used to attain this objective. There appears to be co-movement in stock prices and returns within the CARICOM stock markets and significant dependence structures between the returns of the three CARICOM stock markets. However, there is considerably less evidence of integration between the CARICOM markets and the New York Stock Exchange.  相似文献   
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Consumer “multihoming” (watching two TV channels, or buying two news magazines) has surprisingly important effects on market equilibrium and performance in (two‐sided) media markets. We show this by introducing consumer multihoming and advertising finance into the classic circle model of product differentiation. When consumers multihome (attend more than one platform), media platforms can charge only incremental value prices to advertisers. Entry or merger leaves consumer prices unchanged under consumer multihoming, but leaves advertiser prices unchanged under single‐homing: Multihoming flips the side of the market on which platforms compete. In contrast to standard circle results, equilibrium product variety can be insufficient under multihoming.  相似文献   
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We investigate the impact of direct payments on agricultural commercialisation in Kosovo. Kosovo is one of the poorest countries in Europe but, with European assistance, provides substantial funds to support agriculture, made up of many small and often semi‐subsistence farms. Thus, the effect of this support is a central policy issue. Identifying the effect of direct payments on market participation faces endogeneity issues arising from the possible simultaneous determination of participation in support programmes and market participation. In order to achieve proper identification of the endogenous direct payments, we use a strategy of targeted identification search that employs several different methodological approaches. We find that direct payments for fruit and vegetables, and those for cereals and oilseeds have a positive effect on market participation. However, we cannot identify any definite effect of livestock payments.  相似文献   
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