中国对“一带一路”沿线国家直接投资的碳排放效应

确定中国对外直接投资(OFDI)对CO2排放的影响路径,对"一带一路"沿线国家如何有效利用中国OFDI以实现可持续发展具有重要作用。该研究基于2003—2018年45个沿线国家的面板数据,应用具有阈值和动态特征的面板平滑转换回归(PSTR)模型,评估中国OFDI对CO2排放的直接效应和间接效应、线性效应和非线性效应。研究发现:(1)中国OFDI对沿线国家CO2排放的直接影响显著为负。(2)中国OFDI的规模效应增加了沿线国家CO2排放,其结构效应和技术效应进一步抑制了沿线国家CO2排放,且技术效应在间接效应中占有主导地位。(3)异质性分析表明,中国OFDI的碳减排效应更多体现在低收入国家。针对以上研究发现,文章认为沿线国家应持续引进中国OFDI,并通过提高能效和推广应用清洁能源打破经济发展的"不可持续性";中国政府应继续鼓励并引导具有竞争力的企业"走出去",充分发挥中国投资对东道国环境的改善作用,放大中国投资对低收入国家的技术溢出效应;中国应根据沿线国家经济发展水平对东道国实施差异化投资策略,实现中国投资环境效益最优化。     

Trade-off between fitness components in males of the polygynous butterfly Callophrys xami (Lycaenidae): the effect of multiple mating on longevity

The differential costs of mating paid by males and females influence the nature and strength of sexual selection. In butterflies, males invest a relatively large amount of time and resources in each mating, but male survival costs of mating have not been demonstrated. I present the results of experiments designed to measure the effect of different aspects of mating on male longevity in the polygynous butterfly Callophrys xami. In experiment 1, I compared the longevity of pairs of males that produced similar amounts of spermatophore, but that mated at different rates, a different numbers of times, and that produced spermatophores at different rates, and found that the longevity of ”low-mating-rate” males was not different from that of ”high-mating-rate” males. In experiment 2, the longevity of virgin males was not significantly different from that of multiply mated males. In experiment 3, I used resource-limited males resulting from experimental food limitation of last-instar larvae; resource-limited virgin males lived significantly more days than resource-limited multiply mated males. Since ecological costs of mating (e.g., disease transmission, predation risk) were excluded in the experiment, diminished male longevity was a product of physiological costs of sexual interactions. These results suggest that the cost of ejaculate production is an important cause of longevity reduction when there are resource limitations; however, the role of other possible physiological costs of mating in longevity reduction is still unknown. Received: 21 March 2000 / Accepted: 26 August 2000     

EVALUATION OF THE WORTH OF ADDITIONAL DATA1

ABSTRACT .Inherent in every decision process is a certain amount of uncertainty, which is reduced with information. Perfect knowledge yields no uncertainty for a process, but perfect knowledge for hydrologic and water resource systems would require a highly excessive investment. Therefore, it is the aim of this paper to delineate a procedure that places a value on this uncertainty so that it may be compared to a cost of further investment, which would provide a basis for deciding the time at which the value of additional data does not exceed the cost of that data. A decision theory approach is employed on a hydrologic problem to formalize the steps in making a decision. Examples are given.     

自然保护替代债——一种自然保护投资的手段

为鼓励自然保护与持续发展的投资,同时缓解一些国家所面临的债务危机,80年代中期国际上出现了一个叫做“自然保护替代债”(Debt—for—nature exchange)的投资方式。“自然保护替代债”是在什么样的背景下出现的呢?它是怎样的一种交易呢?参加这一交易的各方将会有哪些得失呢?它的发展前景如何?本文对这方面情况做一扼要介绍,以利有关部门参考。     

MODELING AND SENSITIVITY ANALYSIS FOR PLANNING DECISIONS IN WATER RESOURCES EXPANSION1

ABSTRACT. Individuals and organizations concerned with the expansion of the facilities of a river basin (such as a river basin authority) need to determine optimal strategies of operation and capital investment. They also need to examine the sensitivity of whatever planning decisions are contemplated. This paper extends the applicability of an algorithm that had been previously applied to the deterministic river-basin expansion problem to include the feature of a sensitivity analysis. The algorithm, containing a partial enumeration search technique and a network analysis code, gave a construction sequence of reservoirs, canals, and treatment plants, and an operating policy that maximized the present value of net earnings consistent with certain underlying assumptions. A river basin was chosen that had an existing configuration of unregulated streams and rivers, reservoirs, canals and treatment plants, and sites for future additional facilities. A series of representative synthetic flow sequences, future demand profiles, interest rates and reservoir costs that served as inputs to or parameters in the system were each perturbed by various factors (for a total of 24 cases). The sensitivity studies showed that the immediate planning decision of what facility to construct next was insensitive to variations in future demands and costs and independent of later decisions. Thus, decision-making was adaptive in the sense that by always making the optimal proximate decision, the management of the river basin is optimized.     

环境投资理论研究与发展

本文以现代投资理论和环境经济学的发展需要为线索,认为环境投资理论是两者相结合的产物,并对环境投资理论产生和发展过程进行了分析和评价,从而指出了其今后的研究方向。     

安全经济问题多属性的研究

企业的安全投入包括以增产为目的的生产性投入和以提高劳动安全管理水平及安全防护技术水平为目的的安全性投入。生产性投入占主要部分并决定企业的基本安全程度，安全性投入只占一定的比例，其在生产方面的产出可正可负，因此，安全经济问题具有多属性。安全经济评价或决策属于多目标问题，需采用多目标方法     

考虑环境因素的城镇污水处理投资效率——基于三阶段DEA的方法

运用三阶段DEA模型对剔除环境因素和随机误差因素影响前后的城镇污水处理效率进行测算和比较.研究结果表明：经济、社会和水资源禀赋等环境因素对城市污水处理投资效率具有显著影响,且高估了污水处理的综合技术效率.我国当前城镇污水处理综合技术效率水平不高,仅为0.797;从区域来看,东部和中部综合技术效率较高,西部地区综合技术效率较低.从纯技术效率和规模效率来看,多数省份处于低高型阶段,说明多数省份存在管理技术不足,规模冗余的现象,且我国污水处理率低于污水处理投资效率.因此,在提高污水处理的管理技术水平的同时也要提高污水处理量和污水处理规模的建设.     

中小企业安全管理现状调查与对策研究

近年来,中小企业迅猛发展,为推动经济发展和社会进步发挥了重要作用,与此同时,中小企业安全生产问题也日益突出。为了摸清中小企业安全生产现状,探索有效的安全生产监管办法,江苏省某市在其辖区范围内,选择建筑、化工、非煤矿山、机电4个行业的100家中小企业,就其安全生产状况进行调查。其结果表明:大多数中小企业安全管理基础工作不扎实;安全管理水平普遍不高;不同行业企业间安全投资水平差距较大。针对中小企业安全管理存在的问题,提出了相应的对策:提高中小企业全员安全意识和安全素质;有效促进企业加大安全投资;推行注册安全主任制度;建立市场准入和退出机制;培育安全生产中介组织等。