The Yellow River is famous for its complex and unique physical conditions which give great chal- lenges to the river management. Based on the study and analysis of the existing problems and research progress, this pap...The Yellow River is famous for its complex and unique physical conditions which give great chal- lenges to the river management. Based on the study and analysis of the existing problems and research progress, this paper indicated that the most signifi- cant challenges of Yellow River studies are: long term hydrological and morphological changes; the optimized hydrology and sediment conditions to maintain the healthy life of the River; and simulation of Yellow River through mathematical model and physical models.展开更多
The recycling of suitable organic wastes can enhance soil fertility via effects on soil physical, chemical and biological properties. To compare the effects of digested (DS), thermally dried (TDS) and composted dewate...The recycling of suitable organic wastes can enhance soil fertility via effects on soil physical, chemical and biological properties. To compare the effects of digested (DS), thermally dried (TDS) and composted dewatered (CDS) sewage sludge on soil microbiological properties, an experiment was conducted at field sites for more than one year (401 d) when applied to two Mediterranean degraded soils (loam and loamy sand soils). All three types of sewage sludge had a significant effect on measured parameters. In a short time, the plots of both loamy sand and loam soils amended with TDS showed the highest microbial basal respiration (loam soil: P < 0.01; loamy sand soil: P < 0.001) and carbon mineralization coefficient (loam soil: P < 0.01; loamy sand soil: P < 0.001). Furthermore, on loamy sand soil, the plots amended with TDS showed the highest microbial metabolic quotient (qCO 2 ) (P < 0.05). This study revealed that the addition of sludge caused transient non-equilibrium effects on almost all soil microbial properties. However, there were no differences one year later because the remaining organic carbon was stable and quite similar in all treatments. These results may have practical implications for the rehabilitation of degraded soils.展开更多
文摘The Yellow River is famous for its complex and unique physical conditions which give great chal- lenges to the river management. Based on the study and analysis of the existing problems and research progress, this paper indicated that the most signifi- cant challenges of Yellow River studies are: long term hydrological and morphological changes; the optimized hydrology and sediment conditions to maintain the healthy life of the River; and simulation of Yellow River through mathematical model and physical models.
基金Supported by CIRIT (Consejo Interdepartamental de Investigación e Innovación Tecnológica),the Department of the Environment of the Autonomous Government of Catalonia,and the Spanish Ministry of Education and Science
文摘The recycling of suitable organic wastes can enhance soil fertility via effects on soil physical, chemical and biological properties. To compare the effects of digested (DS), thermally dried (TDS) and composted dewatered (CDS) sewage sludge on soil microbiological properties, an experiment was conducted at field sites for more than one year (401 d) when applied to two Mediterranean degraded soils (loam and loamy sand soils). All three types of sewage sludge had a significant effect on measured parameters. In a short time, the plots of both loamy sand and loam soils amended with TDS showed the highest microbial basal respiration (loam soil: P < 0.01; loamy sand soil: P < 0.001) and carbon mineralization coefficient (loam soil: P < 0.01; loamy sand soil: P < 0.001). Furthermore, on loamy sand soil, the plots amended with TDS showed the highest microbial metabolic quotient (qCO 2 ) (P < 0.05). This study revealed that the addition of sludge caused transient non-equilibrium effects on almost all soil microbial properties. However, there were no differences one year later because the remaining organic carbon was stable and quite similar in all treatments. These results may have practical implications for the rehabilitation of degraded soils.
