Study is made on a 45 km-long artificial ecosystem without irrigation in Tengger desert on the basis of long-term ecological monitoring and ecohydrological fundamentals.Changes in water allocation, utilization, cycle ...Study is made on a 45 km-long artificial ecosystem without irrigation in Tengger desert on the basis of long-term ecological monitoring and ecohydrological fundamentals.Changes in water allocation, utilization, cycle and balance patterns in more than 40-year evolution of the soil-plant system are analyzed. The formation of a drought horizon in shrub rhizosphere and its effect, ecohydrological function of the crust and its effect on the soil-plant system change are discussed. Driven by water self-regulation and water stress, the soil-plant system is going to develop towards the steppe desert to ensure more effective use and optimum collocation of water resource.展开更多
Runoff components are the most important factors in explaining the hydrological behaviour of a system.So that the proper understanding of the runoff processes may effectively help managers and decision-makers adopt ap...Runoff components are the most important factors in explaining the hydrological behaviour of a system.So that the proper understanding of the runoff processes may effectively help managers and decision-makers adopt appropriate measures.In this regard,there are variety of approaches to handle runoff generation,but the application of environmentally friendly,biologic-based and cost-effective approaches such as soil microorganisms has been seldom reported.The study has therefore tried to investigate the role of inoculation of cyanobacteria on runoff components under rain simulation conditions at the mid-sized(i.e.,6×1m)plots installed at=30% slope steepness.The treated plots were subjected to a simulated rainfall with an intensity of 50 mm h^(-1) and an initial duration of 30 min with three replica-tions.A simulated runoff of 2.18±0.32 Lmin^(-1) was also performed simultaneously on the onset of starting surface runoff.The results showed significant differences(P<0.021)in hydrological behaviours in control and treated plots.So that no surface runoff was produced in treated plots up to the end of the initial duration of 30 min of simulated rainfall.The results revealed that cyanobacterization by secretion of exopolysaccharides not only postponed runoff generation but also effectively inhibited runoff com-ponents even if the rainfall incident extended for longer periods.The positive effect of cyanobacterization on increasing infiltration and potential storage of water beneath the soil was also verified in the present study,which suggests the profitable application of cyanobacteria for regulating hydrologic components.展开更多
基金supported by Knowledge Innovation Program,Chinese Academy of Sciences(Grant Nos.KZCX3-SW-324,KZCX1-09)National Natural Science Foundation of China(Grant No.90202015)State Key Technology Research and Development Program(No.2002BA517A11).
文摘Study is made on a 45 km-long artificial ecosystem without irrigation in Tengger desert on the basis of long-term ecological monitoring and ecohydrological fundamentals.Changes in water allocation, utilization, cycle and balance patterns in more than 40-year evolution of the soil-plant system are analyzed. The formation of a drought horizon in shrub rhizosphere and its effect, ecohydrological function of the crust and its effect on the soil-plant system change are discussed. Driven by water self-regulation and water stress, the soil-plant system is going to develop towards the steppe desert to ensure more effective use and optimum collocation of water resource.
基金The Agrohydrology Research Group of Tarbiat Modares University contributed to this analysis in part(Grant No.IG-39713)Later,the Iran National Science Foundation(Project No.98014330)provided partial funding for this study,which is highly appreciated.
文摘Runoff components are the most important factors in explaining the hydrological behaviour of a system.So that the proper understanding of the runoff processes may effectively help managers and decision-makers adopt appropriate measures.In this regard,there are variety of approaches to handle runoff generation,but the application of environmentally friendly,biologic-based and cost-effective approaches such as soil microorganisms has been seldom reported.The study has therefore tried to investigate the role of inoculation of cyanobacteria on runoff components under rain simulation conditions at the mid-sized(i.e.,6×1m)plots installed at=30% slope steepness.The treated plots were subjected to a simulated rainfall with an intensity of 50 mm h^(-1) and an initial duration of 30 min with three replica-tions.A simulated runoff of 2.18±0.32 Lmin^(-1) was also performed simultaneously on the onset of starting surface runoff.The results showed significant differences(P<0.021)in hydrological behaviours in control and treated plots.So that no surface runoff was produced in treated plots up to the end of the initial duration of 30 min of simulated rainfall.The results revealed that cyanobacterization by secretion of exopolysaccharides not only postponed runoff generation but also effectively inhibited runoff com-ponents even if the rainfall incident extended for longer periods.The positive effect of cyanobacterization on increasing infiltration and potential storage of water beneath the soil was also verified in the present study,which suggests the profitable application of cyanobacteria for regulating hydrologic components.
