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171.
The new WIOD database allows for improved empirical analysis on a wide range of important environmental research questions.In this paper we demonstrate the scientific power of the WIOD database and analyze very urgent policy questions on the impacts of international trade and structural change on the environment.We apply recent econometric approaches to show the impact of international trade on the environment via its different channels as for instance to increase welfare and potentially affect environmental regulation as well as countries’sector.This approach has become known as the econometric structural decomposition method.In addition to these guidelines by the literature,an econometric panel data approach is offered to shed some light on the impact of structural change and international trade on environmental pressure,where we especially address and solve several endogeneity issues that add further complexity to the analysis. 相似文献
172.
非农就业对农户种植多样性的影响:以江苏省泰兴市和宿豫区为例 总被引:6,自引:1,他引:5
为分析非农就业对农户种植多样性的影响,通过农户问卷调查手段获得356份农户问卷,以在江苏省泰兴市和宿豫区的农户问卷调查数据为基础,采用Poisson回归方法,估计了农户种植多样性决策模型。依据模型估计结果,分析了非农就业对农户种植多样性的影响。分析表明,农户的种植多样性受到多种因素的影响。负责农业生产家庭成员受教育年限提高1 a,种植多样性提高1.5%左右;种植面积增加1 hm2,则农户种植多样性提高28%左右;就农户参与非农活动的影响而言,与负责农业生产家庭成员不参与非农活动的农户相比较,负责农业生产家庭成员参与非农活动家庭的种植多样性减少11%左右;负责农业生产家庭成员参与非农活动月数增加1个月,农户种植多样性大约降低1.4%。分析说明负责农业生产家庭成员参与非农就业会显著降低农户种植多样性。 相似文献
173.
SUMMARY Long-term cropland fallowing decisions of farmers in the West Nile Province of Uganda were studied. Tabular and regression methods are used to examine the relationship between farm and household factors and seasons of net fallowing. The results show that farmers plan to decrease the rate of fallowing in the immediate future. Serious (but undocumented) problems in maintaining cropland productivity could result. Population density had a large and negative effect on net fallowing (seasons of fallowing less seasons of crops), decreasing from the current average of ?0.6 seasons to ?2.21 seasons for a doubling of population. This 268% decrease in the use of fallowing could occur in as few as 13.5 years, assuming a 3% annual population growth rate. Farms larger in size, but with no increase in per capita cropland availability, had a higher rate of net fallowing. Cashcrop production was negatively associated with net fallowing, whilst farmer age had a positive association. The results have implications for both agricultural policy and guidance for further research on cropland fallowing. Increased cash-cropping should not be recommended unless the full economic costs of using land resources are evaluated. Much of the increased area for cash-crop production would come from fallowed land, decreasing the rate of fallowing and thus increasing the potential for soil degradation. Fallowing has long been used in the area to maintain cropland productivity. Building upon farmers current practices and improving fallowing through the use of green manures and agroforestry could prove to be more economical than the use of mineral fertilizers. Investigating why farms larger in size and those with older head-of-households were able to use fallowing more effectively may provide key information for the development of more productive fallowing technologies. 相似文献
174.
In this paper, I show the existence and the characteristics of equilibrium in a non-renewable resource market where extraction costs are non-convex and market price is subject to stochastic shocks, an empirically relevant setting. In my model firms may be motivated to hold inventories to facilitate production smoothing, which allows them to continue producing at a smooth pace at any instant when extraction ceases, e.g. when reserves are exhausted. This aspect of the model then supports a competitive equilibrium in the presence of non-convex costs. Casual empirical evidence is provided that supports the central features of my model for a variety of non-renewable resources, lending credence to the explanation for equilibrium I propose. 相似文献
175.
David A. Savage 《Disasters》2019,43(4):771-798
This paper outlines why a move towards a complex adaptive systems model of behaviour is required if the goal is to generate better understanding of how individuals and groups interact with their environment in a disaster setting. To accomplish this objective, a bridge must be built between the broader social sciences and behavioural economics to incorporate discipline‐specific insights that are needed to move towards complexity. This is only possible through a deeper understanding of behaviour and how the environment in which they occur can influence actions. It is then that one can counteract the poor behavioural predictions, flawed policies based on myth, inefficient design, and suboptimal outcomes that have flourished in the absence of a complex adaptive systems model. This paper provides a conceptual framework that draws on concepts from across the natural and social sciences, such as behavioural economics, endocrinology, psychology, sociobiology, and sociology in order to build an interactive theory of disaster behaviour. 相似文献
176.
纯氧曝气在城市污水处理中的经济性比较 总被引:3,自引:0,他引:3
李志娟 《城市环境与城市生态》2005,18(1):22-24
就城市污水处理工艺中鼓风曝气系统和纯氧(或富氧)曝气系统,从原理、技术性指标等方面进行了分析和比较,显然纯氧曝气系统比鼓风曝气系统具有一定的优越性。在城市污水处理厂老厂改造和新厂建设中采用纯氧曝气法具有良好的前景。 相似文献
177.
Ting Chen Yingying Zhao Xiaopeng Qiu Xiaoyan Zhu Xiaojie Liu Jun Yin Dongsheng Shen Huajun Feng 《Frontiers of Environmental Science & Engineering》2021,15(2):33
178.
论文基于偏离-份额法的Esteban-Marquillas拓展模型,从份额分量、结构分量、净竞争分量和资源配置分量4方面系统研究了1985—2014年间中国农业生产规模及结构的演进特征。结果表明:1)研究期间,中国农业增加值呈现阶段式增长,种植业和牧业是导致农业增长的主要产业,黄淮海区和长江中下游区是全国农业增长的主要区域。2)八大粮食生产区农业产业份额分量均表现出先剧烈波动、后稳步增长的发展态势;各区域产业结构优势总体较弱且进一步下降;净竞争分量变化具有波动性,种植业、渔业促进区域农业总体竞争力的作用增强,林业和牧业的促进作用减弱;种植业和林业改善区域农业资源配置效应的作用增强,牧业和渔业则相对减弱。3)建议各区域结合产业发展优势,制定相关政策加强区域资源整合、农产品流通与技术合作,促进地区农业稳定发展。研究结果可为我国农业生产结构优化及差异化的发展策略制定提供依据。 相似文献
179.
中国农地细碎化问题研究进展 总被引:37,自引:6,他引:31
为掌握中国农地细碎化问题研究进展,论文采用概括和比较分析的手段,从农地细碎化的概念内涵、主要研究内容、研究方法等方面对农地细碎化研究进行梳理和概括。归纳出已有研究的几个特点:①农地细碎化的内涵较为清晰且已经得到了广泛认可,但对细碎化程度的衡量方法还需进一步深入;②目前的中国农地细碎化研究主要集中在细碎化成因及其对农业生产的影响方面,以其负面影响的研究最为丰富;③农地细碎化与农地流转、土地整理的关系引起了研究的重视,但是目前主要集中于农地流转对减轻细碎化程度的探讨,土地整理对细碎化作用的研究十分缺乏;④农地细碎化研究涉及的主要是回归分析、生产函数模型等经济学研究方法,利用地理空间分析方法和景观生态学方法探讨农地细碎化问题的研究尚未见报道。最后探讨了还需要进一步深入研究的内容。 相似文献
180.
John T Hickey Gustavo E. Diaz 《Journal of the American Water Resources Association》1999,35(5):1053-1067
This paper details a case study of economic and natural system responses to alternative water management policies in the Cache La Poudre River basin, Colorado, 1980–1994. The case study is presented to highlight the value and application of a conceptual integration of economic, salmonid population, physical habitat, and water allocation models. Five alternative regimes, all intended to increase low winter flows, were investigated. Habitat enhancements created by alternative regimes were translated to population responses and economic benefits. Analysis concluded that instream flows cannot compete on the northern Colorado water rental market; cooperative agreements offer an economically feasible way to enhance instream flows; and establishing an instream flow program on the Cache La Poudre River mainstem is a potentially profitable opportunity. The alliance of models is a dynamic multidisciplinary tool for use in professional settings and offers valuable insight for decision-making processes involved in water management. 相似文献