The soil microbial biomass,the living fraction of organic matter,contains energy material organic carbon compounds,which is derived from plant residue generated soil organic matter.This study investigated the relation...The soil microbial biomass,the living fraction of organic matter,contains energy material organic carbon compounds,which is derived from plant residue generated soil organic matter.This study investigated the relationships between microbial biomass C and organic C with environmental parameters.The results indicate that soil microbial biomass is highly sensitive to the changes of environmental conditions in soils,and converts easily to available organic C compounds,and acts as source and sink of energy material C flow.Therefore,it plays an important role in soil organic matter decomposition.The turnover of soil microbial biomass is an important pathway of soil organic matter decomposition.展开更多
In nature selenate reduction and nitrate denitrification both folow a similar biogeochemical mechanism. It has been proved that abiotic stresses such as alternative drying and wetting can exert an important influence ...In nature selenate reduction and nitrate denitrification both folow a similar biogeochemical mechanism. It has been proved that abiotic stresses such as alternative drying and wetting can exert an important influence on nitrate denitrification as well as on selenate reduction. Our experimental results lend great support to the above conclusion.展开更多
This paper describes how to carry out environmental impact assessment in an envi-ronmentally sensitive zone. The principles, the train of thought and methods are proposed in this paper. We have made the water environm...This paper describes how to carry out environmental impact assessment in an envi-ronmentally sensitive zone. The principles, the train of thought and methods are proposed in this paper. We have made the water environmental impact assessment on the engineering pro-ject of technical reform in Guiyang Battery Mill. The basis for engineering construction and environmental protection in this mill has been laid dawn.展开更多
Endemic fluorine disease is a chronic fluorine poisoning caused by high level of fluorine in drinking water or foods. Incidence of this disease has been knowu in many parts of the world. In China its occurrence has be...Endemic fluorine disease is a chronic fluorine poisoning caused by high level of fluorine in drinking water or foods. Incidence of this disease has been knowu in many parts of the world. In China its occurrence has been observed in the Northeast, Northwest, Southwest and some other localities. Investigation shows that it is closely related to geochemical environment: Major fluorine sources in nature include fluorinerich volcanic rocks, calcareous dolomites, phosphorus-bearing rocks/loess and Quarternary loose sediments. Under special conditions fluorine is concentrated in ground water or soil and seeks its way into human body through diet. Areas With high fluorine concentration responsible for the fluorine disease can be classified into four types, depending on characteristics of geochemical environment: (1) Arid and semiarid calcium-rich soda saline areas; (2) Semiarid, alternatively marine-terrestrial strata with a high degree of salinity; (3) Semihumid iron- and aluminum-rich intermediate-acid soils; (4) Localities where fluorine-rich rocks or deposits are developed;and those with high fluorine content as a result of industrial pollution. Based on medical statistics and chemical analyses, of water, soil, food and other related samplcs,this work will provide a scientific baekground for the prevention and control of fluorine disease.展开更多
文摘The soil microbial biomass,the living fraction of organic matter,contains energy material organic carbon compounds,which is derived from plant residue generated soil organic matter.This study investigated the relationships between microbial biomass C and organic C with environmental parameters.The results indicate that soil microbial biomass is highly sensitive to the changes of environmental conditions in soils,and converts easily to available organic C compounds,and acts as source and sink of energy material C flow.Therefore,it plays an important role in soil organic matter decomposition.The turnover of soil microbial biomass is an important pathway of soil organic matter decomposition.
文摘In nature selenate reduction and nitrate denitrification both folow a similar biogeochemical mechanism. It has been proved that abiotic stresses such as alternative drying and wetting can exert an important influence on nitrate denitrification as well as on selenate reduction. Our experimental results lend great support to the above conclusion.
文摘This paper describes how to carry out environmental impact assessment in an envi-ronmentally sensitive zone. The principles, the train of thought and methods are proposed in this paper. We have made the water environmental impact assessment on the engineering pro-ject of technical reform in Guiyang Battery Mill. The basis for engineering construction and environmental protection in this mill has been laid dawn.
文摘Endemic fluorine disease is a chronic fluorine poisoning caused by high level of fluorine in drinking water or foods. Incidence of this disease has been knowu in many parts of the world. In China its occurrence has been observed in the Northeast, Northwest, Southwest and some other localities. Investigation shows that it is closely related to geochemical environment: Major fluorine sources in nature include fluorinerich volcanic rocks, calcareous dolomites, phosphorus-bearing rocks/loess and Quarternary loose sediments. Under special conditions fluorine is concentrated in ground water or soil and seeks its way into human body through diet. Areas With high fluorine concentration responsible for the fluorine disease can be classified into four types, depending on characteristics of geochemical environment: (1) Arid and semiarid calcium-rich soda saline areas; (2) Semiarid, alternatively marine-terrestrial strata with a high degree of salinity; (3) Semihumid iron- and aluminum-rich intermediate-acid soils; (4) Localities where fluorine-rich rocks or deposits are developed;and those with high fluorine content as a result of industrial pollution. Based on medical statistics and chemical analyses, of water, soil, food and other related samplcs,this work will provide a scientific baekground for the prevention and control of fluorine disease.
