我国秸秆综合利用面临形势与对策研究

[目的]为加快推动秸秆资源化利用,促进农业绿色发展。[方法]文章在系统梳理我国秸秆综合利用政策文件、相关文献的基础上,全面分析了我国农作物秸秆禁烧和综合利用的发展阶段,提出了秸秆利用面临的形势和存在的主要问题。[结果]我国秸秆综合利用从时间序列上,可以划分为起步阶段、强力推进阶段和攻坚阶段。城镇化的快速推进、农村能源结构的调整、农业供给侧结构性改革的实施、农作物季节矛盾突出等,成为秸秆综合利用面临的新形势、新挑战。当前推进秸秆综合利用存在四大方面问题:秸秆还田成本较高,区域技术规范和技术适宜性缺乏;受"成本地板"和"价格天花板"双重挤压,秸秆产业化利用发展困难;秸秆收储运成本高,技术装备水平低,用地、运输问题尚未解决,收储运体系建设不健全;关键性政策工具尚未破题,缺乏普惠性、针对性的资金扶持。[结论]针对形势与问题,提出了推进秸秆资源化利用的4条对策建议:开展县域秸秆全量化利用、分区施策确定秸秆利用方向、加强政策工具集成创设、扩大试点示范引导。     

The Resource Curse Hypothesis: Dynamic Heterogeneous Approach

Natural resources influence economic performance through many different mechanisms, both beneficial and harmful. Some of these mechanisms tend to set in fast while others are rather slow. This suggests that pooling the long- and short-run effect as typical in the resource empirical literature may lead to incorrect inferences. This article provides an evaluation of the income contribution of natural resources using a panel cointegration approach that allows for short-run dynamic heterogeneity while imposing the restriction of long-run homogeneity. It finds, in a sample of developing countries over the period 1990–2012, that natural resources are a curse in the long run. The evidence is robust to alternative dynamic specifications, different measures and types of natural resource wealth, and controlling for regional effects.     

自来水供应系统水质风险耦合致因分析

以城市自来水水质事故致因为研究视角,首先识别供水水质风险因素,并从单、双及多因素角度分析供水水质风险因素间的耦合关系,再借助N-K模型对2008—2017年全国所发生的362起城市重大供水水质风险耦合度进行度量。结果表明:城市自来水供应动态系统中,水质风险率随着参与耦合的风险因素的增多而增加;管理因素风险是水质风险的内因,风险管控是规避水质风险的关键;环境因素风险对水质事故的发生起推动作用。     

Material weakness disclosures and restatement announcements: The joint and order effects

We examine differences in stock price, option volatility, and litigation reactions to restatement announcements that are associated with a material weakness (MW) disclosure. Contrasted with restatements that are not associated with any MW disclosure, our analyses reveal that firms that announce both a restatement and an associated MW experience significantly more negative market returns, greater implied volatility, and higher likelihood of class action lawsuits. Separating the restatements into timely reporters, where the MW precedes the restatement, and non‐timely reporters, where the MW is concurrent with or follows the restatement, we find that timely reporters experience more negative returns at the time of the restatement, relative to non‐timely reporters, suggesting that investors perceive the early MW disclosure to signal more pervasive control‐related problems. Interestingly, we find that timely and non‐timely reporters are equally likely to be sued, consistent with the argument that wrongdoing (through either a timely or non‐timely MW disclosure) provides stronger grounds for establishing scienter. However, timely reporters appear to secure more favorable litigation outcomes: they face higher likelihood of lawsuit dismissals and pay much lower settlements, compared to non‐timely reporters. Overall, our evidence provides new insights into how market participants incorporate information about internal control weaknesses into their perceptions regarding the economic implications of financial restatements, and financial reporting quality.     

基于熵值法的高质量发展综合评价研究

探索高质量发展评价指标体系是当前社会各界面临的极富挑战性和开创性工作。从生产、分配、交换和消费四个环节选取23个指标构建高质量发展指标体系,利用熵值法对2000—2015年我国经济高质量发展进行评价。在此基础上从提升全要素生产率、调节国民收入分配格局、助力文化消费以及防范市场风险等层面提出政策建议。     

Supplier Development Practices for Sustainability: A Multi‐Stakeholder Perspective

Supplier development for sustainability is a critical element of sustainable supply chain management and requires extensive multi‐stakeholder collaboration. This article establishes a conceptual four‐stage framework to analyse the collaborative mechanisms of supplier development practices, and presents an exploratory, qualitative analysis to identify the major contributors of sustainable supplier development practices, such as NGOs, industrial associations, consulting firms etc. Based on semi‐structured interviews about 63 organizations from different regions and industries, this article identifies three types of contributor: drivers, facilitators and inspectors. Instead of traditional stakeholder engagement processes, these contributors actively collaborate with buying firms and suppliers to design, implement and evaluate sustainable supplier development programs. The article then provides a matrix to describe the supply chain coverage and supplier performance of supplier development practices, given the absence or positive involvement of facilitators and inspectors. We conclude our study by suggesting future research directions as well as discussing managerial implications. Copyright © 2017 John Wiley & Sons, Ltd and ERP Environment     

城市化进程中的乡村衰落现象：成因及治理——“乡村振兴战略”实施视角的分析

党的十九大报告提出了“实施乡村振兴战略”。乡村振兴是“中国梦”不可或缺的组成部分，城市化进程中的乡村衰落现象不容忽视，乡村问题的解决关系到乡村振兴战略能否实现和现代乡村能否建成。为此，剖析了我国乡村衰落的成因，探索了乡村振兴战略落实的办法，提出了现代乡村建设的可能路径。     

基于SARIMA-SVR组合模型的 空气质量指数预测

空气质量指数(AQI)在波动中既具有整体的时间序列线性特征和明显的季节性波动周期,又具有多种因素影响的不确定性,为了提高AQI的预测精度,基于Ri386 3.3.3和Matlab R2014a两种编程软件,提出了一种同时具有线性和非线性的复合特征的时间序列预测模型——SARIMA-SVR组合模型。以太原市2014年1月—2019年7月的AQI月均值数据为基础,利用SARIMA时间序列模型进行线性预测,利用SVR模型对残差进行非线性预测,加和得到组合预测模型的预测结果,分析比较SARIMA,SVR和SARIMA-SVR这3种模型的预测结果和平均绝对百分比误差。结果表明,组合预测模型发挥了2种模型各自的优势,相较于单一预测模型的预测结果而言,其预测精度更高,稳定性更好。通过此模型得到的空气质量预测结果不仅可为人们的日常生活提供指导,而且可为大气污染的防治工作提供科学依据和借鉴意义。     

Aid for trade and the quality of exports

This article studies how aid for trade (AfT) affects the quality of recipient countries’ exports. It shows that the quality effect is most discernible for AfT for assistance in trade policy: a 50% increase in the value of AfT received in this category is associated with a 0.5–1% increase in the quality of exports to the donor and other OECD countries. On average, the actual AfT received for assistance in trade policy leads to a 2% upgrade of the recipient country in the quality ladder of all developing countries. Around half of this quality effect is driven by the quality improvement of continued products in continued markets (intensive margin), and the other half by the quality upgrading of new products in continued markets and existing products in new markets (extensive margin).     

福鼎市桐江溪卤乙酸分布特征及潮汐影响分析

为了掌握福鼎市桐江溪卤乙酸(HAAs)的含量、时空分布规律及其来源,对水体中HAAs化合物进行取样调查。根据桐江溪水文情势及沿岸特点设置10个取样点,于2017年12月及2018年7月按照涨潮、退潮情况分别对水样进行采集,检测HAAs分布情况,同时将卤乙酸(HAAs)与水质特性、涨退潮进行了相关性分析。研究发现,HAAs是普遍存在于桐江溪中的污染物质。其中,一氯乙酸(MCAA)、二氯乙酸(DCAA)、三氯乙酸(TCAA)、一溴乙酸(MBAA)、二溴乙酸(DBAA)等5种卤乙酸(HAA_5)质量浓度为0.44～3.39μg/L;一氯乙酸(MCAA)、二氯乙酸(DCAA)、三氯乙酸(TCAA)、一溴乙酸(MBAA)、二溴乙酸(DBAA)、三溴乙酸(TBAA)、一溴一氯乙酸(BCAA)、一溴二氯乙酸(BDCAA)、二溴一氯乙酸(CBDAA)等9种卤乙酸(HAA_9)质量浓度为0.83～56.15μg/L。桐江溪中HAAs主要为DCAA,TCAA,TBAA 3种,其中DCAA为制药厂及医院排水导致,主要分布在下游;TCAA主要来源于河段上游的农业生产活动;TBAA为上游沸石矿尾矿库受雨水冲刷而流入的Br~-所生成,主要分布于河流中下段。相关性分析结果表明,温度与HAA_5,HAA_9质量浓度呈现正相关,pH值与HAA_5,HAA_9质量浓度呈现负相关;TCAA质量浓度于相同季节不同潮汐及不同季节相同潮汐时均呈现上游高于下游的现象,其他HAAs均不因涨潮、退潮的差异造成质量浓度分布的变化。掌握桐江溪HAAs的含量、时空分布规律及来源,探讨其与水质的相关性,对于净水工艺选择、水厂出水HAAs含量的溯源分析、水体环境风险评估以及研究水生生物体内HAAs的累积效应等有重要意义。