Mechanized direct sowing of rapeseed is a labor-saving and highly-efficient culture technique. In order to explore high-yield cultivation techniques suitable for Chengdu Plain, effects of several key agronomic measure...Mechanized direct sowing of rapeseed is a labor-saving and highly-efficient culture technique. In order to explore high-yield cultivation techniques suitable for Chengdu Plain, effects of several key agronomic measures', such as sowing date, density and N fertilizers, on development and yield formation were studied by strip and split plot experiment of three factors. The research showed that optimal condi- tions for direct seeding technology can be achieved provided with scientific sowing date, density and appropriate N fertilizers, and the research showed that rapeseed yield reached the peak at 320 g/m2, when sowing date was on September 3th, sow- ing density was 30 plant/m2, and nitrogen fertilizer was 27 g/m2.展开更多
In order to remedy the injuryof agriculture produced by concession ofentering WTO, China can adopt someprotective measures, such as safeguardmeasures. Only if the relevant conditions aresatisfied, the safeguard measur...In order to remedy the injuryof agriculture produced by concession ofentering WTO, China can adopt someprotective measures, such as safeguardmeasures. Only if the relevant conditions aresatisfied, the safeguard measures can belegitimate. Under WTO, two kinds ofsafeguard measures for protectingagricultural products can be implemented,general one and special one. They are quitedifferent, and thus discussed in details in thisarticle.展开更多
The Songhua River Basin is a burgeoning agricultural area in the modern times in China. Particularly in recent years, increasing chemical fertilizers and pesticides have been applied with the development of agricultur...The Songhua River Basin is a burgeoning agricultural area in the modern times in China. Particularly in recent years, increasing chemical fertilizers and pesticides have been applied with the development of agricultural production. However, the situation of non- point source pollution (NSP) from agricultural production in this basin is still obscure. In order to solve the problem, the occurrence and distribution of acetochlor in sediments and riparian soils of the Songhua River Basin before rain season and after rain season were investigated. In addition, total organic carbon was analyzed. The result showed that the concentration of acetochlor ranged from 0.47 to 11.76 μg/kg in sediments and 0.03 to 709.37 μg/kg in riparian soils. During the high flow period in 2009, the mean concentration was 4.79 μg/kg in sediments and 0.75 μg]kg in riparian soils, respectively. Similarly, the mean concentration was 2.53 μg/kg in sediments and 61.36μg/kg in riparian soils, during the average flow period in 2010. There was a significant correlation between the concentration of acetochlor and total organic carbon in surface sediments. Moreover, the distribution of acetochlor in sediments of the Songhua River was significantly correlated to land use and topography of the watershed. The investigated data suggested that the concentration of acetochlor in the Songnen Plain and the Sanjiang Plain was higher than that in the other areas of the basin, and riparian buffering zones in these areas bad been destroyed by human activities. The optimal agricultural measures to alleviate the contamination of pesticides should be adopted, including controlling agricultural application of acetochlor and ecological restoration of riparian buffering strips.展开更多
Cadmium is one of the important contaminative heavy metals. Due to continuous increase of discharge of Cadmium in industrial and agriculture production, cadmium contamination of soil is more and more serious day by da...Cadmium is one of the important contaminative heavy metals. Due to continuous increase of discharge of Cadmium in industrial and agriculture production, cadmium contamination of soil is more and more serious day by day, which seriously threatens ecological environment and human health. Treatment of cadmium becomes an urgent issue and research hot point. At present, remedy for cadmium pollution upon soil mainly are physical restoration, chemical restoration and biological restoration, also there are measurements by means of adding external source matter and selecting low-Cd-accumulation varieties so as to reduce cadmium harm upon agricultural products. This article introduces in detail the resource of cadmium in soil and the present condition of cadmium pollution in farmland and processing of domestic cadmium pollution research, processing stage of domestic and foreign research of restoration of cadmium polluted soil as well as various peculiarities of repair methods. Finally, the expectation of research is discussed.展开更多
基金Supported by Special Fund for Agro-scientific Research in the Public Interest(200903050-4)National Public Science and Technology Research Funds Project(201303129)~~
文摘Mechanized direct sowing of rapeseed is a labor-saving and highly-efficient culture technique. In order to explore high-yield cultivation techniques suitable for Chengdu Plain, effects of several key agronomic measures', such as sowing date, density and N fertilizers, on development and yield formation were studied by strip and split plot experiment of three factors. The research showed that optimal condi- tions for direct seeding technology can be achieved provided with scientific sowing date, density and appropriate N fertilizers, and the research showed that rapeseed yield reached the peak at 320 g/m2, when sowing date was on September 3th, sow- ing density was 30 plant/m2, and nitrogen fertilizer was 27 g/m2.
文摘In order to remedy the injuryof agriculture produced by concession ofentering WTO, China can adopt someprotective measures, such as safeguardmeasures. Only if the relevant conditions aresatisfied, the safeguard measures can belegitimate. Under WTO, two kinds ofsafeguard measures for protectingagricultural products can be implemented,general one and special one. They are quitedifferent, and thus discussed in details in thisarticle.
基金supported by the National Special Water Project in China (No. 2008ZX07526-002-01)
文摘The Songhua River Basin is a burgeoning agricultural area in the modern times in China. Particularly in recent years, increasing chemical fertilizers and pesticides have been applied with the development of agricultural production. However, the situation of non- point source pollution (NSP) from agricultural production in this basin is still obscure. In order to solve the problem, the occurrence and distribution of acetochlor in sediments and riparian soils of the Songhua River Basin before rain season and after rain season were investigated. In addition, total organic carbon was analyzed. The result showed that the concentration of acetochlor ranged from 0.47 to 11.76 μg/kg in sediments and 0.03 to 709.37 μg/kg in riparian soils. During the high flow period in 2009, the mean concentration was 4.79 μg/kg in sediments and 0.75 μg]kg in riparian soils, respectively. Similarly, the mean concentration was 2.53 μg/kg in sediments and 61.36μg/kg in riparian soils, during the average flow period in 2010. There was a significant correlation between the concentration of acetochlor and total organic carbon in surface sediments. Moreover, the distribution of acetochlor in sediments of the Songhua River was significantly correlated to land use and topography of the watershed. The investigated data suggested that the concentration of acetochlor in the Songnen Plain and the Sanjiang Plain was higher than that in the other areas of the basin, and riparian buffering zones in these areas bad been destroyed by human activities. The optimal agricultural measures to alleviate the contamination of pesticides should be adopted, including controlling agricultural application of acetochlor and ecological restoration of riparian buffering strips.
基金Supported by the National Natural Science Foundation of China(20477032)China Agriculture Research System(Nycytx-25)
文摘Cadmium is one of the important contaminative heavy metals. Due to continuous increase of discharge of Cadmium in industrial and agriculture production, cadmium contamination of soil is more and more serious day by day, which seriously threatens ecological environment and human health. Treatment of cadmium becomes an urgent issue and research hot point. At present, remedy for cadmium pollution upon soil mainly are physical restoration, chemical restoration and biological restoration, also there are measurements by means of adding external source matter and selecting low-Cd-accumulation varieties so as to reduce cadmium harm upon agricultural products. This article introduces in detail the resource of cadmium in soil and the present condition of cadmium pollution in farmland and processing of domestic cadmium pollution research, processing stage of domestic and foreign research of restoration of cadmium polluted soil as well as various peculiarities of repair methods. Finally, the expectation of research is discussed.