The stability of aggregates in the surface soil is crucial to soil erosion and runoff generation. Thus, to understand the stability and the breakdown mechanisms of soil aggregates as well as the relationship between a...The stability of aggregates in the surface soil is crucial to soil erosion and runoff generation. Thus, to understand the stability and the breakdown mechanisms of soil aggregates as well as the relationship between aggregate stability and selected soil chemical properties, such as different forms of Fe and Al oxides, organic matter, CEC and clay content, the aggregates of slightly and severely eroded red soils derived from Quaternary red clay in subtropical China were analyzed using the routine wet sieving…展开更多
Dalian, Shenyang, Changchun and Harbin are the four core cities which play an essential role in terms of promoting the economic development in Northeast China. In this paper, the impact of urban agglomeration on labor...Dalian, Shenyang, Changchun and Harbin are the four core cities which play an essential role in terms of promoting the economic development in Northeast China. In this paper, the impact of urban agglomeration on labor productivity is explored by making comparisons among these four cities. The model used for analysis is a classical model derived from previous studies. Some indicators, such as population density and economic density, were selected to examine the impact of urban agglomeration on the labor productivity based on the time-series data for the four cities from 1990 to 2007. The four main conclusions are： l） The promotion from the growth rate of population density on the growth rate of labor productivity is limited. 2） The negative relationship exists between the growth rate of employment density and the growth rate of labor productivity. 3） Agglomeration effect exists in the four cities, the highest one is Dalian, Shenyang takes the second place, followed by Changchun and Harbin, and the predominant promotion exerted on the labor productivity is the output density.展开更多
In economic literature, the term ＇flying geese＂ refers to the movement of capital from developed regions to less developed ones. Using national data from abovescale manufacturing enterprises, this paper investigates...In economic literature, the term ＇flying geese＂ refers to the movement of capital from developed regions to less developed ones. Using national data from abovescale manufacturing enterprises, this paper investigates whether the experience of ＂flying geese＂ has transpired in China for manufacturing industries. We find that, driven by the effects of agglomeration, prior to the mid-2000s, there had been an increasing concentration of industrial activities in the coastal regions. However, as labor and land costs increased, the manufacturing sector - especially the labor-intensive industries - began to relocate from the coastal to the interior regions.展开更多
Agglomeration of economic activities is a common phenomenon across the world. Theoretical and empirical studies have shown that agglomeration promotes dynamic efficiency, which in turn is conducive to the long-term pr...Agglomeration of economic activities is a common phenomenon across the world. Theoretical and empirical studies have shown that agglomeration promotes dynamic efficiency, which in turn is conducive to the long-term prosperity of a country＇s economy. Compared with most countries, in China is very low, and Chinese cities the spatial concentration of various industries are relatively small and equal-sized. Thus, it is unnecessary to contain the agglomeration of economic activities in China. Widening regional gaps since pro-market reforms and opening-up in China should be ascribed to institutional barriers rather than agglomeration. Therefore, China should refrain from containing agglomeration and instead focus on integrating product and factor markets and improving education and health care in less developed areas.展开更多
With the acceleration of the rise of central China and the western development drive, industrial relocation from China＇s eastern region to the central and western regions is in full swing. However, does the relocatio...With the acceleration of the rise of central China and the western development drive, industrial relocation from China＇s eastern region to the central and western regions is in full swing. However, does the relocation demonstrate industrial clustering effect？ Empirical studies based on twenty two-digit manufacturing industries in 27provinces from 2000 to 2009 demonstrate that industrial clustering effect appeared in central and western regions which had undertaken industrial relocation from eastern region; however, the studies do not show excessive administrative interference as evidenced by the significantly improved productivity of the relocated industries. Compared with non-labor- intensive manufacturing industries, labor-intensive manufacturing industries are easier to form cyclic accumulative effects. Studies also revealed that improvement in supporting infrastructure, industrial chain and higher labor quality in non-agriculture employment during urbanization are significant for central and western regions to undertake industrial relocation.展开更多
Soil organic carbon （SOC） and iron （Fe）-oxides are important contributors of aggregate stability in highly weathered soils, and they are influenced by groundwater management and straw application. A 30-year plot e...Soil organic carbon （SOC） and iron （Fe）-oxides are important contributors of aggregate stability in highly weathered soils, and they are influenced by groundwater management and straw application. A 30-year plot experiment with early rice （Oryza sativa L.）-late rice-winter fallow rotations was conducted using a upland clay soil in cement pools under shallow groundwater table at a depth of 20 am （SGT） aud deep groundwater table at a depth of 80 cm （DGT） to simulate the groundwater tables of two types of important paddy soils, gleyed paddy soils and hydromorphic paddy soils, respectively, in subtropical China. Soil redox potential （Eh） was measured in situ, and 0-20 cm soil samples were collected for the analyses of soil Fe-oxides, SOC, and aggregates under SGT or DGT with different straw application treatments, in order to evaluate the interaction of groundwater management and straw application on paddy soil aggregation and the relative importance of SOC or Fe-oxides on soil aggregation. The results showed that soil Eh was restricted by irrigation, and its variation was more significant under DGT than under SGT. The decreased soil Eh or reduced drying and wetting cycles under SGT resulted in more SOC accumulation with the straw application, had no effect on soil free Fe-oxides （Fed）, significantly increased the amorphous Fe-oxide （Feo） and complex Fe-oxide contents, but decreased the crystalline Fe-oxide content （Fed-Feo）. The soils under DGT had more macroaggregates than those under SGT, but the difference decreased with the straw application. It could be concluded that soil Fe-oxides were the principal contributing factor to the aggregation of paddy soils in subtropical China and SOC was also an important contributing factor.展开更多
文摘The stability of aggregates in the surface soil is crucial to soil erosion and runoff generation. Thus, to understand the stability and the breakdown mechanisms of soil aggregates as well as the relationship between aggregate stability and selected soil chemical properties, such as different forms of Fe and Al oxides, organic matter, CEC and clay content, the aggregates of slightly and severely eroded red soils derived from Quaternary red clay in subtropical China were analyzed using the routine wet sieving…
基金Under the auspices of National Natural Science Foundation of China (No. 41071088)National Social Science Foundation of China (No. 08BJY056)
文摘Dalian, Shenyang, Changchun and Harbin are the four core cities which play an essential role in terms of promoting the economic development in Northeast China. In this paper, the impact of urban agglomeration on labor productivity is explored by making comparisons among these four cities. The model used for analysis is a classical model derived from previous studies. Some indicators, such as population density and economic density, were selected to examine the impact of urban agglomeration on the labor productivity based on the time-series data for the four cities from 1990 to 2007. The four main conclusions are： l） The promotion from the growth rate of population density on the growth rate of labor productivity is limited. 2） The negative relationship exists between the growth rate of employment density and the growth rate of labor productivity. 3） Agglomeration effect exists in the four cities, the highest one is Dalian, Shenyang takes the second place, followed by Changchun and Harbin, and the predominant promotion exerted on the labor productivity is the output density.
文摘In economic literature, the term ＇flying geese＂ refers to the movement of capital from developed regions to less developed ones. Using national data from abovescale manufacturing enterprises, this paper investigates whether the experience of ＂flying geese＂ has transpired in China for manufacturing industries. We find that, driven by the effects of agglomeration, prior to the mid-2000s, there had been an increasing concentration of industrial activities in the coastal regions. However, as labor and land costs increased, the manufacturing sector - especially the labor-intensive industries - began to relocate from the coastal to the interior regions.
文摘Agglomeration of economic activities is a common phenomenon across the world. Theoretical and empirical studies have shown that agglomeration promotes dynamic efficiency, which in turn is conducive to the long-term prosperity of a country＇s economy. Compared with most countries, in China is very low, and Chinese cities the spatial concentration of various industries are relatively small and equal-sized. Thus, it is unnecessary to contain the agglomeration of economic activities in China. Widening regional gaps since pro-market reforms and opening-up in China should be ascribed to institutional barriers rather than agglomeration. Therefore, China should refrain from containing agglomeration and instead focus on integrating product and factor markets and improving education and health care in less developed areas.
文摘With the acceleration of the rise of central China and the western development drive, industrial relocation from China＇s eastern region to the central and western regions is in full swing. However, does the relocation demonstrate industrial clustering effect？ Empirical studies based on twenty two-digit manufacturing industries in 27provinces from 2000 to 2009 demonstrate that industrial clustering effect appeared in central and western regions which had undertaken industrial relocation from eastern region; however, the studies do not show excessive administrative interference as evidenced by the significantly improved productivity of the relocated industries. Compared with non-labor- intensive manufacturing industries, labor-intensive manufacturing industries are easier to form cyclic accumulative effects. Studies also revealed that improvement in supporting infrastructure, industrial chain and higher labor quality in non-agriculture employment during urbanization are significant for central and western regions to undertake industrial relocation.
基金financially supported by the National Natural Science Foundation of China (No. 41371250)
文摘Soil organic carbon （SOC） and iron （Fe）-oxides are important contributors of aggregate stability in highly weathered soils, and they are influenced by groundwater management and straw application. A 30-year plot experiment with early rice （Oryza sativa L.）-late rice-winter fallow rotations was conducted using a upland clay soil in cement pools under shallow groundwater table at a depth of 20 am （SGT） aud deep groundwater table at a depth of 80 cm （DGT） to simulate the groundwater tables of two types of important paddy soils, gleyed paddy soils and hydromorphic paddy soils, respectively, in subtropical China. Soil redox potential （Eh） was measured in situ, and 0-20 cm soil samples were collected for the analyses of soil Fe-oxides, SOC, and aggregates under SGT or DGT with different straw application treatments, in order to evaluate the interaction of groundwater management and straw application on paddy soil aggregation and the relative importance of SOC or Fe-oxides on soil aggregation. The results showed that soil Eh was restricted by irrigation, and its variation was more significant under DGT than under SGT. The decreased soil Eh or reduced drying and wetting cycles under SGT resulted in more SOC accumulation with the straw application, had no effect on soil free Fe-oxides （Fed）, significantly increased the amorphous Fe-oxide （Feo） and complex Fe-oxide contents, but decreased the crystalline Fe-oxide content （Fed-Feo）. The soils under DGT had more macroaggregates than those under SGT, but the difference decreased with the straw application. It could be concluded that soil Fe-oxides were the principal contributing factor to the aggregation of paddy soils in subtropical China and SOC was also an important contributing factor.
