A field experiment was conducted to study the combined effect of nutrient andpest managements on soil biomass phospholipid contents, functional biodiversity and substrateutilization patterns of soil microbial populati...A field experiment was conducted to study the combined effect of nutrient andpest managements on soil biomass phospholipid contents, functional biodiversity and substrateutilization patterns of soil microbial populations in hybrid rice cropping system. The mineral N, Pand K fertilizers (as urea, calcium superphosphate and KCl respectively) were incorporated at 100,25, and 100 kg ha^(-1), respectively, and the various pesticides were applied at the recommendedrates. The results of the experiment demonstrated a decline in the microbial abundance and soilmicrobial biomass phospholipid contents with the advancement of crop growth, and significant changesin substrate utilization pattern of soil microbial population studied were observed with differentmanagement practices and at different growth stages. The principal component analysis (PCA) usingall 95-carbon sources (BIOLOG plates) gave good differentiation among the treatments, indicatingthat they have different patterns of carbon utilization under different habitats. The data showedthat diversity in microbial community continuously changed with the progression in crop stage,particularly at physiological maturity (PM) stage that was evident from the utilization of differentcarbon sources at various crop stages.展开更多
A large portion of irrigation farmers make use of subjective (intuition) irrigation scheduling methods as supposed to objective or scientific irrigation scheduling methods, which need to be changed. The BEsproeiings...A large portion of irrigation farmers make use of subjective (intuition) irrigation scheduling methods as supposed to objective or scientific irrigation scheduling methods, which need to be changed. The BEsproeiingsWAterbestuursprogram (BEWAB+) irrigation scheduling programme is based on the water balance equation and needs: (1) a crop production function; (2) a relative consumptive water demand curve and (3) an allowable depletion subroutine. The objective of this paper was to describe research aimed at obtaining information on (1) and (2) for pea and also to describe the effect of water application on yield and water use of pea. BEWAB+ uses this information to estimate the daily irrigation water requirements for a particular soil-crop-atmosphere system under irrigation. A field experiment, based on published line-source irrigation methodology, was conducted on a 3 m deep loamy fine sand Bainsvlei or Ustic Quartzipsamment soil near Bloemfontein (26°08′S; 29°01′E) in South Africa. Results showed that there is a linear relationship of the form Ys = 8.07ET - 249 (r2 = 0.91), where Ys is the seed yield of pea (kg/ha) and ET is evapotranspiration for the growing season (mm). The relative consumptive water demand curve is represented by the following third order polynomial function that describes the relationship between time and relative ET for a pea growing season of 120 days: ETrelx = 0.09419646 - 0.01302413x + 0.00059008x2 - 0.00000371x3. ETrelz denotes relative ET and x denotes time in days. A workable balance between practical problem solving and advanced irrigation science has been established with BEWAB+. Pre-plant irrigation schedules can be made for semi-arid areas with the BEWAB+ programme using easily obtainable inputs, like target yield, soil depth and soil particle size distribution information.展开更多
The present study deals with the Water Quality Index (WQI) and absorption of zinc from electroplating industry effluent using ftmgi. The physico-chemical parameters such as EC (Electrical Conductivity), TDS (Tota...The present study deals with the Water Quality Index (WQI) and absorption of zinc from electroplating industry effluent using ftmgi. The physico-chemical parameters such as EC (Electrical Conductivity), TDS (Total Dissolved Solids), total hardness, magnesium, calcium, chloride, sodium, potassium, nickel, chromium and zinc content was above the permissible limits of BIS (Bureau of Indian Standards). The WQI was 13, which showed that the pollution level of the electroplating industry effluent was severe in the rating scale and the effluent was not suitable for disposal without treatment. Three fungal species such as Aspergillus niger, Peinicillium chrysogenum and Rhizopus nigricans were used for absorption studies. Different concentrations (25, 50, 75 and 100%) of electroplating industry effluent along with 1 gm of fungal mycelium with (1%) and without carbon source was incubated in a shaker for a period of 7 days in order to observe zinc absorption capacity. The absorption capacity of zinc was found to be higher in Aspergillus niger followed by Rhizopus nigricans and Penicillium chrysogenum. Among the three fungal species Aspergillus niger had high (50%) potential of zinc absorption with carbon source and low concentration (25%) of electroplating industry effluent.展开更多
A systems approach is used to describe the generation and variation of wastewater in an urban area. This is a multivariable system and its combined response at the outlet of this system, which is usually the entrance ...A systems approach is used to describe the generation and variation of wastewater in an urban area. This is a multivariable system and its combined response at the outlet of this system, which is usually the entrance ofa wastewater treatment plant, depends on a number of environmental (precipitation and temperature) as well as social (size of the urban area, population changes, water consumption per capita) variables. There is a large number of available models and tools for describing the urban water system, however, the interactions between the individual components are rarely considered within the same modelling framework. In this paper a parsimonious methodology is proposed in order to understand and estimate the wastewater generation and its characteristics in an urban area using any information provided by the available data. The model incorporates both the flows of stormwater discharge and wastewater production that arrive to the wastewater treatment plant. A state dependent variable is introduced to simulate the consumptive uses in the urban area. Data availability and system's complexity affect the ability to achieve enhanced model performance, however, in the presented case study, preliminary results from the application of the presented model in the Greater Athens Area illustrate the potential of the conceptual modelling approach.展开更多
An approach for short-term forecasting of municipal water consumption was presented based on the largest Lyapunov exponent of chaos theory. The chaotic characteristics of time series of urban water consumption were ex...An approach for short-term forecasting of municipal water consumption was presented based on the largest Lyapunov exponent of chaos theory. The chaotic characteristics of time series of urban water consumption were examined by means of the largest Lyapunov exponent and correlation dimension. By using the largest Lyapunov exponent a short-term forecasting model for urban water consumption was developed, which was compared with the artificial neural network (ANN) approach in a case study. The result indicates that the model based on the largest Lyapunov exponent has higher prediction precision and forecasting stability than the ANN method, and its forecasting mean relative error is 9.6% within its maximum predictable time scale while it is 60.6% beyond the scale.展开更多
基金the National Natural Science Foundation of China.
文摘A field experiment was conducted to study the combined effect of nutrient andpest managements on soil biomass phospholipid contents, functional biodiversity and substrateutilization patterns of soil microbial populations in hybrid rice cropping system. The mineral N, Pand K fertilizers (as urea, calcium superphosphate and KCl respectively) were incorporated at 100,25, and 100 kg ha^(-1), respectively, and the various pesticides were applied at the recommendedrates. The results of the experiment demonstrated a decline in the microbial abundance and soilmicrobial biomass phospholipid contents with the advancement of crop growth, and significant changesin substrate utilization pattern of soil microbial population studied were observed with differentmanagement practices and at different growth stages. The principal component analysis (PCA) usingall 95-carbon sources (BIOLOG plates) gave good differentiation among the treatments, indicatingthat they have different patterns of carbon utilization under different habitats. The data showedthat diversity in microbial community continuously changed with the progression in crop stage,particularly at physiological maturity (PM) stage that was evident from the utilization of differentcarbon sources at various crop stages.
文摘A large portion of irrigation farmers make use of subjective (intuition) irrigation scheduling methods as supposed to objective or scientific irrigation scheduling methods, which need to be changed. The BEsproeiingsWAterbestuursprogram (BEWAB+) irrigation scheduling programme is based on the water balance equation and needs: (1) a crop production function; (2) a relative consumptive water demand curve and (3) an allowable depletion subroutine. The objective of this paper was to describe research aimed at obtaining information on (1) and (2) for pea and also to describe the effect of water application on yield and water use of pea. BEWAB+ uses this information to estimate the daily irrigation water requirements for a particular soil-crop-atmosphere system under irrigation. A field experiment, based on published line-source irrigation methodology, was conducted on a 3 m deep loamy fine sand Bainsvlei or Ustic Quartzipsamment soil near Bloemfontein (26°08′S; 29°01′E) in South Africa. Results showed that there is a linear relationship of the form Ys = 8.07ET - 249 (r2 = 0.91), where Ys is the seed yield of pea (kg/ha) and ET is evapotranspiration for the growing season (mm). The relative consumptive water demand curve is represented by the following third order polynomial function that describes the relationship between time and relative ET for a pea growing season of 120 days: ETrelx = 0.09419646 - 0.01302413x + 0.00059008x2 - 0.00000371x3. ETrelz denotes relative ET and x denotes time in days. A workable balance between practical problem solving and advanced irrigation science has been established with BEWAB+. Pre-plant irrigation schedules can be made for semi-arid areas with the BEWAB+ programme using easily obtainable inputs, like target yield, soil depth and soil particle size distribution information.
文摘The present study deals with the Water Quality Index (WQI) and absorption of zinc from electroplating industry effluent using ftmgi. The physico-chemical parameters such as EC (Electrical Conductivity), TDS (Total Dissolved Solids), total hardness, magnesium, calcium, chloride, sodium, potassium, nickel, chromium and zinc content was above the permissible limits of BIS (Bureau of Indian Standards). The WQI was 13, which showed that the pollution level of the electroplating industry effluent was severe in the rating scale and the effluent was not suitable for disposal without treatment. Three fungal species such as Aspergillus niger, Peinicillium chrysogenum and Rhizopus nigricans were used for absorption studies. Different concentrations (25, 50, 75 and 100%) of electroplating industry effluent along with 1 gm of fungal mycelium with (1%) and without carbon source was incubated in a shaker for a period of 7 days in order to observe zinc absorption capacity. The absorption capacity of zinc was found to be higher in Aspergillus niger followed by Rhizopus nigricans and Penicillium chrysogenum. Among the three fungal species Aspergillus niger had high (50%) potential of zinc absorption with carbon source and low concentration (25%) of electroplating industry effluent.
文摘A systems approach is used to describe the generation and variation of wastewater in an urban area. This is a multivariable system and its combined response at the outlet of this system, which is usually the entrance ofa wastewater treatment plant, depends on a number of environmental (precipitation and temperature) as well as social (size of the urban area, population changes, water consumption per capita) variables. There is a large number of available models and tools for describing the urban water system, however, the interactions between the individual components are rarely considered within the same modelling framework. In this paper a parsimonious methodology is proposed in order to understand and estimate the wastewater generation and its characteristics in an urban area using any information provided by the available data. The model incorporates both the flows of stormwater discharge and wastewater production that arrive to the wastewater treatment plant. A state dependent variable is introduced to simulate the consumptive uses in the urban area. Data availability and system's complexity affect the ability to achieve enhanced model performance, however, in the presented case study, preliminary results from the application of the presented model in the Greater Athens Area illustrate the potential of the conceptual modelling approach.
基金Supported by National Natural Science Foundation of China (No.50578108) .
文摘An approach for short-term forecasting of municipal water consumption was presented based on the largest Lyapunov exponent of chaos theory. The chaotic characteristics of time series of urban water consumption were examined by means of the largest Lyapunov exponent and correlation dimension. By using the largest Lyapunov exponent a short-term forecasting model for urban water consumption was developed, which was compared with the artificial neural network (ANN) approach in a case study. The result indicates that the model based on the largest Lyapunov exponent has higher prediction precision and forecasting stability than the ANN method, and its forecasting mean relative error is 9.6% within its maximum predictable time scale while it is 60.6% beyond the scale.