本文根据Antras et al的模型测算了中国35个行业的下游度,大多数行业下游度小于0.5,处于分工位置的上游,特别是制造业在分工位置上不具有优势;服务业和金融业处于价值链的高端。中国行业下游度变化趋势为先上升后下降,最终呈现分工位置...本文根据Antras et al的模型测算了中国35个行业的下游度,大多数行业下游度小于0.5,处于分工位置的上游,特别是制造业在分工位置上不具有优势;服务业和金融业处于价值链的高端。中国行业下游度变化趋势为先上升后下降,最终呈现分工位置下滑的态势。同时,本文利用面板数据OLS、2SLS和分位数回归进行实证检验,得出以下结论:分工位置下滑扩大了不同技能劳动力间的工资差距;非熟练劳动力间工资差距的扩大主要受分工位置50百分位以下的影响;处于分工位置中端的行业的收入差距受分工位置变动的影响较小;熟练劳动力间工资差距的扩大主要受分工位置两端的影响,越接近下游,工资差距有所缓和,但仍是扩大趋势。最后,对中国稳定劳动力间的工资差距提出政策建议。展开更多
The summer rainfall over the middle-lower reaches of the Yangtze River valley (YRSR) has been estimated with a multi-linear regression model using principal atmospheric modes derived from a 500 hPa geopotential height...The summer rainfall over the middle-lower reaches of the Yangtze River valley (YRSR) has been estimated with a multi-linear regression model using principal atmospheric modes derived from a 500 hPa geopotential height and a 700 hPa zonal vapor flux over the domain of East Asia and the West Pacific.The model was developed using data from 1958 92 and validated with an independent prediction from 1993 2008.The independent prediction was efficient in predicting the YRSR with a correlation coefficient of 0.72 and a relative root mean square error of 18%.The downscaling model was applied to two general circulation models (GCMs) of Flexible Global Ocean-Atmosphere-Land System Model (FGOALS) and Geophysical Fluid Dynamics Laboratory coupled climate model version 2.1 (GFDL-CM2.1) to project rainfall for present and future climate under B1 and A1B emission scenarios.The downscaled results pro-vided a closer representation of the observation compared to the raw models in the present climate.In addition,compared to the inconsistent prediction directly from dif-ferent GCMs,the downscaled results provided a consistent projection for this half-century,which indicated a clear increase in the YRSR.Under the B1 emission scenario,the rainfall could increase by an average of 11.9% until 2011 25 and 17.2% until 2036 50 from the current state;under the A1B emission scenario,rainfall could increase by an average of 15.5% until 2011 25 and 25.3% until 2036 50 from the current state.Moreover,the increased rate was faster in the following decade (2011 25) than the latter of this half-century (2036 50) under both emissions.展开更多
Vertical distribution of soil nematode communities under conventional tillage (CT),no-tillage (NT) and fallow field (FF) treatments in the Lower Reaches of the Liaohe River was investigated at six soil depths (0-5 cm,...Vertical distribution of soil nematode communities under conventional tillage (CT),no-tillage (NT) and fallow field (FF) treatments in the Lower Reaches of the Liaohe River was investigated at six soil depths (0-5 cm,5-15 cm,15-30 cm,30-50 cm,50-75 cm and 75-100 cm). The results show that total nematode abundance gradually decreases with depth,and the highest number of total nematodes is observed at 0-5 cm depth under NT and FF treatments. The number of fungivores and plant parasites is significantly higher under FF and NT treatments than under CT treatment at the 0-5 cm depth. There is significant soil depth effect on the abundances of bacterivores and omnivores-predators,which exhibits a similar trend to that of total nematodes; whereas,no significant tillage effect is found. Tillage effect on soil nematode communities can be reflected by values of relative tillage response of index V. Results of index V indicate that total nematodes,bacterivores,fungivores and plant parasites are mildly inhibited,and omnivores-predators is moderately inhibited under CT treatment; while,under FF treatment total nematodes is mildly,and fungivores and plant parasites are moderately stimulated,respectively.展开更多
企业在全球价值链中的位置,关系到企业的治理能力和绩效,进而影响一国的经济发展质量乃至国际地位。本文从增加值视角重新阐述了全球价值链位置测度和结构分解方法,并改进了Chor et al.(2014)的企业位置测度方法,进而实证测算分析了中...企业在全球价值链中的位置,关系到企业的治理能力和绩效,进而影响一国的经济发展质量乃至国际地位。本文从增加值视角重新阐述了全球价值链位置测度和结构分解方法,并改进了Chor et al.(2014)的企业位置测度方法,进而实证测算分析了中国企业在全球价值链中的位置及其结构变化。研究发现:(1)2000—2014年中国整体上游度和生产复杂度显著提高,产业链向上游延伸。(2)一般贸易企业的综合进出口位置、出口上游度高于加工贸易企业,但进口下游度低于加工贸易企业。一般贸易企业出口产品更多地用于中间投入品,离最终需求的距离相对较远,进口相对上游产品进行生产,而加工贸易一般进口相对下游的产品进行简单组装加工形成最终消费品再出口。(3)东部地区企业的综合进出口位置、出口上游度相对较低,偏向于最终消费品出口,而进口下游度较大,偏向于进口基本成型的中间品,体现了东部地区的加工组装特点。(4)相对于其他所有制类型企业,国有企业各类出口上游度相对较高但进口下游度相对较低,进而导致国有企业的综合进出口位置最高。此外,企业全要素生产、人均工资水平和资本密集度对企业出口上游度具有正向影响,而企业规模的影响为负。展开更多
文摘本文根据Antras et al的模型测算了中国35个行业的下游度,大多数行业下游度小于0.5,处于分工位置的上游,特别是制造业在分工位置上不具有优势;服务业和金融业处于价值链的高端。中国行业下游度变化趋势为先上升后下降,最终呈现分工位置下滑的态势。同时,本文利用面板数据OLS、2SLS和分位数回归进行实证检验,得出以下结论:分工位置下滑扩大了不同技能劳动力间的工资差距;非熟练劳动力间工资差距的扩大主要受分工位置50百分位以下的影响;处于分工位置中端的行业的收入差距受分工位置变动的影响较小;熟练劳动力间工资差距的扩大主要受分工位置两端的影响,越接近下游,工资差距有所缓和,但仍是扩大趋势。最后,对中国稳定劳动力间的工资差距提出政策建议。
基金supported by the National Basic Research Program of China (Grant No.2010CB950400)the National Natural Science Foundation of China (Key Project,Grant No.41030961)the Australia-China Bilateral Climate Change Partnerships Program of the Australian Department of Climate Change
文摘The summer rainfall over the middle-lower reaches of the Yangtze River valley (YRSR) has been estimated with a multi-linear regression model using principal atmospheric modes derived from a 500 hPa geopotential height and a 700 hPa zonal vapor flux over the domain of East Asia and the West Pacific.The model was developed using data from 1958 92 and validated with an independent prediction from 1993 2008.The independent prediction was efficient in predicting the YRSR with a correlation coefficient of 0.72 and a relative root mean square error of 18%.The downscaling model was applied to two general circulation models (GCMs) of Flexible Global Ocean-Atmosphere-Land System Model (FGOALS) and Geophysical Fluid Dynamics Laboratory coupled climate model version 2.1 (GFDL-CM2.1) to project rainfall for present and future climate under B1 and A1B emission scenarios.The downscaled results pro-vided a closer representation of the observation compared to the raw models in the present climate.In addition,compared to the inconsistent prediction directly from dif-ferent GCMs,the downscaled results provided a consistent projection for this half-century,which indicated a clear increase in the YRSR.Under the B1 emission scenario,the rainfall could increase by an average of 11.9% until 2011 25 and 17.2% until 2036 50 from the current state;under the A1B emission scenario,rainfall could increase by an average of 15.5% until 2011 25 and 25.3% until 2036 50 from the current state.Moreover,the increased rate was faster in the following decade (2011 25) than the latter of this half-century (2036 50) under both emissions.
基金Under the auspices of Knowledge Innovation Programs of Chinese Academy of Sciences (No. KZCX2-YW-445)the Science and Technology Program of Liaoning Province (No. 2009403053)
文摘Vertical distribution of soil nematode communities under conventional tillage (CT),no-tillage (NT) and fallow field (FF) treatments in the Lower Reaches of the Liaohe River was investigated at six soil depths (0-5 cm,5-15 cm,15-30 cm,30-50 cm,50-75 cm and 75-100 cm). The results show that total nematode abundance gradually decreases with depth,and the highest number of total nematodes is observed at 0-5 cm depth under NT and FF treatments. The number of fungivores and plant parasites is significantly higher under FF and NT treatments than under CT treatment at the 0-5 cm depth. There is significant soil depth effect on the abundances of bacterivores and omnivores-predators,which exhibits a similar trend to that of total nematodes; whereas,no significant tillage effect is found. Tillage effect on soil nematode communities can be reflected by values of relative tillage response of index V. Results of index V indicate that total nematodes,bacterivores,fungivores and plant parasites are mildly inhibited,and omnivores-predators is moderately inhibited under CT treatment; while,under FF treatment total nematodes is mildly,and fungivores and plant parasites are moderately stimulated,respectively.
文摘企业在全球价值链中的位置,关系到企业的治理能力和绩效,进而影响一国的经济发展质量乃至国际地位。本文从增加值视角重新阐述了全球价值链位置测度和结构分解方法,并改进了Chor et al.(2014)的企业位置测度方法,进而实证测算分析了中国企业在全球价值链中的位置及其结构变化。研究发现:(1)2000—2014年中国整体上游度和生产复杂度显著提高,产业链向上游延伸。(2)一般贸易企业的综合进出口位置、出口上游度高于加工贸易企业,但进口下游度低于加工贸易企业。一般贸易企业出口产品更多地用于中间投入品,离最终需求的距离相对较远,进口相对上游产品进行生产,而加工贸易一般进口相对下游的产品进行简单组装加工形成最终消费品再出口。(3)东部地区企业的综合进出口位置、出口上游度相对较低,偏向于最终消费品出口,而进口下游度较大,偏向于进口基本成型的中间品,体现了东部地区的加工组装特点。(4)相对于其他所有制类型企业,国有企业各类出口上游度相对较高但进口下游度相对较低,进而导致国有企业的综合进出口位置最高。此外,企业全要素生产、人均工资水平和资本密集度对企业出口上游度具有正向影响,而企业规模的影响为负。
