南方丘陵区新增耕地质量空间特征研究*——以江西省宜春市为例

［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。     

川西北高原藏区农村贫困化分异机制探测

[目的]客观揭示农村贫困化地域分异机制,为科学推进川西北高原藏区精准扶贫创新途径、综合战略和认真贯彻落实中央治藏方略提供参考依据。[方法]应用地理探测器模型、GIS空间分析与地统计方法等方法,探测川西北高原藏区贫困村单位面积GDP分异的主导因素,揭示农村贫困化分异机制,提出不同贫困化地域类型的扶贫政策措施。[结果]影响川西北高原藏区农村贫困化分异的主导因素包括到主要交通道路距离、归一化植被指数(NDVI)、土地利用、年均温度和海拔高程等,各因素对贫困村经济发展分异的解释力分别为80. 76%、12. 82%、8. 82%、5. 45%和3. 96%;贫困村经济发展贫困化的分异机制存在明显差异,可归纳为交通区位约束型、自然环境约束型和经济区位约束型等三大类型;农村贫困化驱动机制下的贫困村精准扶贫政策措施亟需因地制宜、科学推进、讲求实效,有序推进精准扶贫战略。[结论]精准扶贫应分类指导、重点突破,尤其加强贫困村交通、水利、公共基础设施建设和特色农牧业产业培植,注重多种扶贫模式的综合集成。     

是否应该征收含糖饮料消费税? ——基于消费税职能的探讨

基于我国减税降费背景下消费税理应秉持的职能定位,本文对征收含糖饮料消费税可能产生的影响展开定量分析.结果表明:征收含糖饮料消费税能够为政府的消费税收入带来至少2％的增幅,同时可以降低居民的能量摄入和体重;尽管存在微弱的收入分配负效应,相对于含糖饮料过量摄入引起的健康负外部性导致的经济损失,征税带来的收益比较可观.本文建议将含糖饮料消费税作为引导居民健康饮食消费的一个切入点,通过逐步扩大税目的方式最终形成契合我国国情的不健康食品消费税.     

The heterogeneous relationship between board social ties and corporate environmental responsibility in an emerging economy

Firms in emerging economies are faced with multiple, incompatible institutional forces in their environmental activities. Which of these forces will be dominant and instantiated within an organization is partly determined by the social relationships that a firm maintains with external actors. This paper investigates the relationship between board social ties and the level of environmental responsibility undertaken by firms in China, an emerging economy, by categorizing board social ties into three types in terms of the three isomorphic forces in the institutional field (coercive, normative and mimetic). Drawing on institutional and agency theories, using a sample of listed firms in environmentally sensitive industries, and a generalized least squares regression method, the results provide empirical evidence that ties that are linked to coercive and normative forces (i.e., political organizations and universities) are related to a higher level of environmental responsibility; however, those that are linked to mimetic forces (i.e., industrial peers) have a negative association with environmental responsibility, which is mitigated by CEO power. These findings suggest that the heterogeneous effects of board social ties on environmental responsibilities experienced by firms in a context of environmentalism are at an early stage.     

水权配置视角下新型农业节水机制和路径研究

加快实施最严格水资源管理制度的重要目标是形成以节水为目标的新的社会运行机制和社会治理模式。农民在农业灌溉中自发形成的用水组织是这一变革中的重要社会力量。通过对农民用水协会特征的分析,认为在"水权配置"的视角下,发展与规范农民用水组织,变原有农业用水过程中的行政管控为社会治理,是建立农业"节水型"社会并支持其良好运行的重要保障,并就如何健全农民用水组织的内部治理结构、克服农民用水组织自身的消极因素提出了建议。     

Factor Heterogeneity,Factor Market Imperfection and Trade

This paper develops a tractable model of examining how factor heterogeneity and imperfect factor market interact for determining a pattern of trade. Institution plays a crucial role for the interaction. In my work, firm productivity is defined as a composition of factor productivity and technology. Thus, input selection should affect the pattern of Melitz’s intra-industry allocation due to the incurring transaction cost. For a simple model, I assume two factors (labor and capital) and two sectors, which are relatively less institution-dependent and relatively more institution-dependent. When the economy is open, effect of the transaction cost on income distribution is more drastic for an institutionally underdeveloped country. Depending on institutional quality, the economic openness reallocates resource across countries through job creation or job destruction. The job turnovers redistribute income between heterogeneous labors within countries. The income redistribution is catalyzed by international mobility of capital. As a result, income disparity is widened between the institutionally developed country and the institutionally underdeveloped country. This paper can contribute to the literature of institution and international trade.     

中国区域农业科技资源配置能力及比较优势研究*——基于省级农业科学院视角

[目的]通过测算各地区农业科技资源的配置能力,分析其比较优势并找出不足以便弥补差距,促进各区域农业科技配置能力的提高,为各地区农业经济的发展提供支持。省级农业科学院作为各省市规模最大、综合实力最强的农业科研机构,是农业科技创新的重要主体之一,分析其科技资源配置能力具有重要的现实意义。[方法]基于2009—2016年相关数据,遴选了有代表性的评价指标体系,运用突变级数法计算农业科技资源配置能力,运用NRCA模型定量分析农业科技资源配置效益的比较优势。[结果]山东农业科学院科技资源配置能力位居全国第一,甘肃、江苏、青海农业科学院分别在农业科技人力、物力、财力资源方面具有明显的比较优势。[结论]省级农业科学院科技资源配置能力区域差异十分明显,但区域格局变化不大,且大致与各地区经济实力相吻合;农业科技资源配置能力较高的农业科学院大多在农业科技物力资源配置效益方面具有比较优势,在农业科技人力、财力资源配置效益方面不具备比较优势。     

The effect of corporate real estate ownership on R&D innovation: credit relief vs. resource replacement in China

Against the background of supply-side structural reform and the real estate financialisation in China, this study investigates the impact of real estate holdings on R&D investment using data of enterprises listed on the Shanghai and Shenzhen stock exchanges. Our empirical results yield five main findings. First, enterprises holding more real estate assets face more serious financial constraints, thus restraining corporate innovation efficiency. Second, when the profit margin gap between entity enterprises and the real estate industry is larger, enterprises are more inclined to transfer industrial capital into the real estate industry, thus reducing R&D investment. Third, when the degree of marketisation is high, intensified market competition, the optimal allocation of factor and product markets, and stronger patent protection will weaken the restraining effect of corporate real estate holdings on R&D investment. Fourth, monopoly enterprises obtain potential profits more than undertaking risks from the real estate industry, they are more willing to hold real estate, thus strengthening the restraining effect of real estate holdings on innovation. Finally, investors' regional preference intensifies the restraining effect of corporate real estate holdings on R&D investment. Our empirical evidence can guide entity enterprises on how to effectively balance short-term (non-productive) and long-term (productive) capital investment.     

金融科技对传统银行行为的影响——基于互联网理财的视角

本文使用2011-2015年263家银行的年报数据和北京大学数字金融研究中心基于蚂蚁金服用户数据构建的地市级数字金融普惠指数,探究金融科技的发展对银行行为的影响。研究发现金融科技的发展实质上推动了一种变相的利率市场化,改变了银行的负债端结构,使得银行负债端越来越依赖于同业拆借等批发性资金。负债端结构的改变导致银行资产端风险承担偏好上升,但是借贷利率和净息差都有所下降。即银行选择了更高风险的资产来弥补负债端成本上升所造成的损失,但并没有将成本向下游企业转移。此外,本文还发现规模越大的银行受到金融科技的冲击越小。