In order to clarify the influence of microbial agents on kitchen waste and rice straw composting, an aerobic composting experiment was conducted by setting three kinds of combined bacterial agents to study the tempera...In order to clarify the influence of microbial agents on kitchen waste and rice straw composting, an aerobic composting experiment was conducted by setting three kinds of combined bacterial agents to study the temperature change in the composting, and pH value, nutrient contents, C/N and heavy metal content after composting through. The three kinds of combined bacterial agents were as follows:B1 with effective strains: Bacillus subtilis, yeast and Trichoderma sp.;B2 with effective strains: Bacillus amyloliquefaciens, yeast and lactic acid bacteria;B3 with effective strains: Bacillus subtilis, yeast and lactic acid bacteria. Results showed that the addition of microbial agents had signifcant effects on temperature change,nitrogen and phosphorus content and C/N of the compost. T1, T2, and T3 treatments lasted for 8, 5 and 4 d in the thermophilic phase above 60℃, respectively. The total nitrogen content of each treatment was 14.90, 15.50 and 13.80 g/kg respectively after composting. The total phosphorus content of each treatment was 4.87, 4.17 and 3.70g/kg respectively at the end of composting. The C/N of each treatment was 20.94,22.63, and 22.65 respectively at the end of composting. The application effect of B1bacteria agent on the composting of kitchen waste and rice straw was better.展开更多
On site composting of organic household wastes is an economical and environmentally tiiendly way to manage municipal wastes. In this manuscript authors evaluated the importance of turning the wastes and of inoculating...On site composting of organic household wastes is an economical and environmentally tiiendly way to manage municipal wastes. In this manuscript authors evaluated the importance of turning the wastes and of inoculating microorganisms and worms in order to unprove the composting process at domestic scale. Four treatments (Control without turning- C-, Control with Turning- CT- inoculated Mountain Microorganism with turning- MM- and Worms without turning- W-) were tested in a random experiment with tour replicates. Sixteen composting bins were fed with 300 kg of organic wastes from a local street market. The process of compostnig lasted 13 weeks after which all the composts were sifted and submitted to a range of chemical, physical and biological analysis. According to the results MM slightly increased the initial temperature and enzymatic activiry. This investigation outcome don't provide of sufficient grounds for a precise recommendation about worms inoculation in compost bins. A decrease between 75% and 80% in the fresh weight of the organic waste was found in the first thirteen weeks after starting the composting process in all the treatments. The quality level of the compost was acceptable, with very low heavy metal content. Turn over helps to keep the product hygienic especially after the inoculation with MM microbial starts. In conclusion and according to the results of this investigation, the use of 320 L compost bins for the organic waste management is strongly advisable.展开更多
Atrazine is a widely used herbicide for controlling weeds on both agricultural and nonagricultural land,which is equally detected in water supplies beyond safe concentrations.Although the presence of atrazine metaboli...Atrazine is a widely used herbicide for controlling weeds on both agricultural and nonagricultural land,which is equally detected in water supplies beyond safe concentrations.Although the presence of atrazine metabolites is an indication of herbicide degradation,some of them still exhibit toxicity,greater water solubility and weaker interaction with soil components than atrazine.Hence,studies with atrazine in the environment are of interest because of its potential to contaminate drinking water sources.Data on atrazine availability for transport,plant uptake,and microbial degradation and mineralization are therefore required to perform more comprehensive and realistic environmental risk assessments of its environmental fate.This review presents an account of the sorption-desorption phenomenon of atrazine on soil and other sorbents by revisiting the several mechanisms of atrazine-sorbent binding reported in the literature.The retention and transport of atrazine in soils;the influence of organic matter on atrazine sorption;the interactions of atrazine with humic substances,atrazine uptake by plants,atrazine bioccumulation and microbial degradation;atrazine transformation in composting environments;and finally atrazine removal by biosorption are discussed.展开更多
文摘In order to clarify the influence of microbial agents on kitchen waste and rice straw composting, an aerobic composting experiment was conducted by setting three kinds of combined bacterial agents to study the temperature change in the composting, and pH value, nutrient contents, C/N and heavy metal content after composting through. The three kinds of combined bacterial agents were as follows:B1 with effective strains: Bacillus subtilis, yeast and Trichoderma sp.;B2 with effective strains: Bacillus amyloliquefaciens, yeast and lactic acid bacteria;B3 with effective strains: Bacillus subtilis, yeast and lactic acid bacteria. Results showed that the addition of microbial agents had signifcant effects on temperature change,nitrogen and phosphorus content and C/N of the compost. T1, T2, and T3 treatments lasted for 8, 5 and 4 d in the thermophilic phase above 60℃, respectively. The total nitrogen content of each treatment was 14.90, 15.50 and 13.80 g/kg respectively after composting. The total phosphorus content of each treatment was 4.87, 4.17 and 3.70g/kg respectively at the end of composting. The C/N of each treatment was 20.94,22.63, and 22.65 respectively at the end of composting. The application effect of B1bacteria agent on the composting of kitchen waste and rice straw was better.
文摘On site composting of organic household wastes is an economical and environmentally tiiendly way to manage municipal wastes. In this manuscript authors evaluated the importance of turning the wastes and of inoculating microorganisms and worms in order to unprove the composting process at domestic scale. Four treatments (Control without turning- C-, Control with Turning- CT- inoculated Mountain Microorganism with turning- MM- and Worms without turning- W-) were tested in a random experiment with tour replicates. Sixteen composting bins were fed with 300 kg of organic wastes from a local street market. The process of compostnig lasted 13 weeks after which all the composts were sifted and submitted to a range of chemical, physical and biological analysis. According to the results MM slightly increased the initial temperature and enzymatic activiry. This investigation outcome don't provide of sufficient grounds for a precise recommendation about worms inoculation in compost bins. A decrease between 75% and 80% in the fresh weight of the organic waste was found in the first thirteen weeks after starting the composting process in all the treatments. The quality level of the compost was acceptable, with very low heavy metal content. Turn over helps to keep the product hygienic especially after the inoculation with MM microbial starts. In conclusion and according to the results of this investigation, the use of 320 L compost bins for the organic waste management is strongly advisable.
文摘Atrazine is a widely used herbicide for controlling weeds on both agricultural and nonagricultural land,which is equally detected in water supplies beyond safe concentrations.Although the presence of atrazine metabolites is an indication of herbicide degradation,some of them still exhibit toxicity,greater water solubility and weaker interaction with soil components than atrazine.Hence,studies with atrazine in the environment are of interest because of its potential to contaminate drinking water sources.Data on atrazine availability for transport,plant uptake,and microbial degradation and mineralization are therefore required to perform more comprehensive and realistic environmental risk assessments of its environmental fate.This review presents an account of the sorption-desorption phenomenon of atrazine on soil and other sorbents by revisiting the several mechanisms of atrazine-sorbent binding reported in the literature.The retention and transport of atrazine in soils;the influence of organic matter on atrazine sorption;the interactions of atrazine with humic substances,atrazine uptake by plants,atrazine bioccumulation and microbial degradation;atrazine transformation in composting environments;and finally atrazine removal by biosorption are discussed.