碳排放交易制度与企业创新质量:抑制还是促进

近年来,有关环境规制与企业创新关系的研究大量涌现,但基于中国碳排放交易制度,尤其是从微观企业层面考察碳排放交易制度对企业创新质量影响的研究仍有待丰富和深化。有鉴于此,采用2008—2016年中国A股上市公司面板数据,以专利申请总量表示创新数量,以发明专利申请和实用新型专利申请分别表示高质量创新和低质量创新,进而采用DID模型构建中国碳排放交易制度对企业创新质量影响的准自然实验框架。同时,为增强实证结果的解释力,采用PSM-DID方法对实证结果进行了稳健性检验、异质性检验以及政府补贴方式的创新激励机制检验。结果表明:①碳排放交易制度在提高"处理组"企业创新数量的同时,也能促使企业兼顾创新质量,但从影响程度来看,碳排放交易制度对低质量创新促进作用更为强劲。②从企业所有权和规模异质性来看,碳排放交易制度主要对国有股份企业和大规模企业创新质量有促进作用,而对民营企业和小规模企业进行高质量创新的诱导力度较小或不显著。③机制检验结果表明,政府补贴政策能够有效弥补碳排放交易制度对高质量创新诱导乏力的不足,但创新激励效果因政府补贴方式而异,其中政府事前补贴优于政府事后补偿;此外,碳排放交易制度通过促使政府为被规制企业提供更多的政府事前补贴,从而有效缓解企业"遵循成本"压力,推动企业转向高质量创新。由此认为,加大对小规模民营企业高质量创新补贴、采取更具灵活性和针对性的创新补贴方式,应是进一步助力碳排放交易制度诱导企业转向高质量创新的政策制定方向。     

国外排污许可制度实践经验与启示

本文从法律法规体系、管理体系、许可证类型、实施程序、与环评的衔接、制度特点的角度,系统梳理了美国、德国、澳大利亚等国家排污许可制度的实践经验,并在此基础上对国外排污许可制度的内涵和实施特点进行总结,从借鉴国外经验和管理的角度,提出完善我国排污许可制度的建议。     

Constructing regional scenarios for sustainable agriculture in European Russia and Ukraine for 2000 to 2070

This study estimates the consequences of climate change on cropland with and without implementation of adaptation measures, paying special attention to the maintenance of soil organic carbon (C) stocks. We examine the possibility for regional sustainable agricultural management practice that combines both maintenance and gain in soil carbon level with profit maximization. Future scenarios of Regional Agricultural Production Systems (RAPS) were constructed for 2000–2070 based on linking the effects of global climate change, predicted change in productivity parameters for the main agricultural crops, land-use and soil database parameters. The RAPS were used to examine profitability and feasibility of alternative agricultural scenarios, based on an economic model. A number of recommendations for decision making were proposed based on an assessment of the efficiency of adaptation in animal husbandry and in the crop production sector, after analysis of current percentage of perennial grass in rotation in comparison with future economic scenarios. Figures in color are available at     

Econometric analysis of the determinants of adoption of alley farming by farmers in the forest zone of southwest Cameroon

Slash-and-burn agriculture continues to expand in many parts of the forest zone of Cameroon. One alternative land use to slash-and-burn system is alley farming. This paper quantifies, using an econometric model, the factors determining farmers’ adoption and use of alley farming variants in southwest of Cameroon, based on a survey of 156 farmers in 11 villages in the region.The analysis showed that male farmers are more likely to adopt than women. Adoption is higher for farmers with contacts with extension agencies working on agroforestry technologies. Adoption is higher for farmers belonging to farmers’ groups. Adoption is lower for farmers in areas with very high population pressure, as farmers in such areas may have greater labor productivity from use of less labor intensive natural resource management technologies like chemical fertilizers. Adoption is higher for farmers in areas facing fuel wood scarcity. Farmers have made adaptations to the conventional alley farming technology recommended by researchers, the most significant adaptation being the introduction of fallow periods into the system. Farmers use alley farming as a land use option, not as a replacement for the slash-and-burn system, since land supply is still relatively elastic. Achieving increased impact with alley farming variants requires effective targeting. Results showed that econometric modeling using farmer and village characteristics, socioeconomic and institutional variables can lead to more effective targeting to farmers and locations where higher adoption rates may occur.     

我国农业与农村可持续发展的制度创新

我国农业与农村可持续发展的核心问题是农民收入问题。只有切实提高农民的收入水平。才能有效地增加农民购买力，从而增加农业生产资料的投入。进而保证粮食增产。我国农业与农村可持续发展存在的两个矛盾是小农经济与市场经济社会化的矛盾以及小农经济与科技化之间的矛盾。面临的两个分离是家庭经济与集体经济的分离以及传统供销合作社与农民利益的分离。增加农民收入的规模经济论与乡镇企业论的确有成功的典范．但是。对我国更多的农村地区来讲．不具有普遍意义。我国农业和农村可持续发展的关键有两个．一是符合区域特色的区域农业专业化．二是通过专业合作社的制度创新．将分散的家庭组织起来．以解决家庭小生产与大市场之间的巨大矛盾。     

川江流域的土壤退化与防治

川江流域地区土壤退化按肥力因素分类，并以专家系统确定的指标分类统计表明：土壤物理性退化中以水分不调、过砂和板结化较严重；土壤结构性退化中，以土层浅薄化较显著；土壤营养性退化中，以缺硼、钼、磷较突出，成因主要是生态脆弱、土壤侵蚀作用和过渡开发利用，据此提出了防治退化的基本措施。并从持续发展角度提出了适应该区土壤退化特点的持续农业系统。     

有关全球气候变化问题上的公平性分析

从《联合国气候变化》了发，对人类社会应对气候变化中的“公平”性问题，从不同角度进行了系统讨论。对发展中国家和发达国家在公平原则下责任、义务及优先事项的差别进行了分析，提出并分析了以人均碳排放权相等为标准，到目标年（例2100年）各国人均碳排放量及过渡期内（例1990-2100）人均累积碳排放量两个趋同的碳排放权分配原则。     

Emission Inventories of Carbon-containing Greenhouse Gases in China and Technological Measures for Their Abatement

The report summarizes surveys on carbon inventories and initiatives on sustainable carbon cycling taken by the Research Center for Eco-Environmental Sciences, where the authors work/worked. The first part of the report, which appeared in the preceding issue of this journal, deals with the concept of sustainable carbon cycling, the historic evolution of carbon cycling processes in China, carbon pool enhancement, value addition, carbon sequestration and carbon balance. This very paper, as the second part of the report, covers the results of carbon dynamics modeling, emission inventories of various carbon-containing greenhouse gases and their potential abatement measures.     

Elemental Analysis of Water and Sediments by External Beam Pixe Part 3: Axios (Vardar) River, Greece

The Axios (Vardar) River originates from the south west part of Yugoslavia, transverses Greece, and discharges into the Thermaikos bay in the north Aegean Sea.

The proton induced X-ray emission (PIXE) method with external beam was used for the elemental analysis of water and sediment samples, while measurements of water temperature, dissolved oxygen content, conductivity, pH, and the water flow were made in situ. Water samples were also analysed for total phosphates, nitrates, chlorophyll, and BOD. The data collected for a 16-month period indicate that the Axios River is polluted as far as the metal content is concerned; its primary productivity is low and it is slightly enriched during its course into the Greek territory.     

三峡库区大农业的自然环境现状与预警分析

根据系统序化的观点，分析了库区大农业主要环境因子的具有代表性指标的数量和警式线，并进行了对比，发现它们都处地逆向演替或退化之中。这对三峡水库和库区大农业均十分有害。说明库区大农业的环境恶劣或恶化，应处于警式状态之中。其主要原因是长期向自然过度索取，以牺牲环境为代价，发展人口和物质的生产。建议进一步研究大农业及其环境的调控；把对环境的逐步补救和防止新的破坏结合起来，开展新的生态建设工程。