Two pollution zones in middle and lower reaches of Hanjiang River were selected for studying restoration processes. In each zones 6 stations were set up in upper stream of sewage outfall, 50m, 100 or 150m, 250 or 525m...Two pollution zones in middle and lower reaches of Hanjiang River were selected for studying restoration processes. In each zones 6 stations were set up in upper stream of sewage outfall, 50m, 100 or 150m, 250 or 525m and 1250 or 3500m apart from the outfall. Chemical monitoring and microbial community biomonitoring were carried out simultaneously. Either the chemical monitoring or the biological monitoring proved the self-purification process of water body along with the increased distance from the sewage outfall. 4 biological parameters (species number of protozoa, percentage of phytomastigophora, diversity index and heterotrophy index) and parameter Seq of the colonization process all have statistically significant correlations with chemical comprehensive pollution indexes Pa and Pb.展开更多
Japan has experienced many large-scale natural disasters, such as earthquakes, typhoons accompanied by heavy rain, and landslides. Based on data for the damage caused by four recent major earthquakes in Japan, we inve...Japan has experienced many large-scale natural disasters, such as earthquakes, typhoons accompanied by heavy rain, and landslides. Based on data for the damage caused by four recent major earthquakes in Japan, we investigate the trends in the number of evacuees and evacuation centres after these disasters as well as the restoration processes for public utilities such as electricity, gas, water, and communication lines. We compare the restoration speeds and trends of the damaged infrastructure systems. We also propose various mathematical models to approximate the recovery trends using both evacuee-related data and damage recovery process data. These results can be used to design natural disaster mitigation policies not only in Japan, but also in other countries. The results of various statistical data analyses and mathematical modelling techniques are applied to provide policy suggestions.展开更多
Dear Editor,Biological soil crusts(BSCs),a layered structure formed by associations of soil organisms and topsoil,dominate arid and semiarid areas and serve important ecological functions in these areas(Eldridge and G...Dear Editor,Biological soil crusts(BSCs),a layered structure formed by associations of soil organisms and topsoil,dominate arid and semiarid areas and serve important ecological functions in these areas(Eldridge and Greene,1994).Nitrogen fixation by BSCs is the main source of N in arid and semi-arid ecosystems.Desiccation is the most notable factor that influences BSCs,which recover physiological activity only after moistening.By influencing the amount of carbohydrates,展开更多
文摘Two pollution zones in middle and lower reaches of Hanjiang River were selected for studying restoration processes. In each zones 6 stations were set up in upper stream of sewage outfall, 50m, 100 or 150m, 250 or 525m and 1250 or 3500m apart from the outfall. Chemical monitoring and microbial community biomonitoring were carried out simultaneously. Either the chemical monitoring or the biological monitoring proved the self-purification process of water body along with the increased distance from the sewage outfall. 4 biological parameters (species number of protozoa, percentage of phytomastigophora, diversity index and heterotrophy index) and parameter Seq of the colonization process all have statistically significant correlations with chemical comprehensive pollution indexes Pa and Pb.
文摘Japan has experienced many large-scale natural disasters, such as earthquakes, typhoons accompanied by heavy rain, and landslides. Based on data for the damage caused by four recent major earthquakes in Japan, we investigate the trends in the number of evacuees and evacuation centres after these disasters as well as the restoration processes for public utilities such as electricity, gas, water, and communication lines. We compare the restoration speeds and trends of the damaged infrastructure systems. We also propose various mathematical models to approximate the recovery trends using both evacuee-related data and damage recovery process data. These results can be used to design natural disaster mitigation policies not only in Japan, but also in other countries. The results of various statistical data analyses and mathematical modelling techniques are applied to provide policy suggestions.
基金supported by the Special Fund for Forest Scientific Research in the Public Welfare of China (201404204-02)
文摘Dear Editor,Biological soil crusts(BSCs),a layered structure formed by associations of soil organisms and topsoil,dominate arid and semiarid areas and serve important ecological functions in these areas(Eldridge and Greene,1994).Nitrogen fixation by BSCs is the main source of N in arid and semi-arid ecosystems.Desiccation is the most notable factor that influences BSCs,which recover physiological activity only after moistening.By influencing the amount of carbohydrates,
