This paper studied the change in soil animal community in contaminated and irrigated area by organophosphorus pesticide waste water and its mechanism was discussed. The results showed that the species and quantities o...This paper studied the change in soil animal community in contaminated and irrigated area by organophosphorus pesticide waste water and its mechanism was discussed. The results showed that the species and quantities of soil animals decreased with organophosphorus pesticide pollution degree increasing. The species of soil animals decreased with average and rare population mainly decreasing, while the amount change was associated with that of the dominant population of Acarina, Collembola and Nematoda. Toxicity experiment demonstrated that the respiration intensity of soil animal was restrained obviously by pesticide pollution. After observation of SEM, the effect of pesticide pollution on the earthworm (\%Pheretima robusta)\% stomach intestinal mucosa damage has been observed, which showed the pesticide contamination may damage the earthworms bodies. Ulcerous focus and perforation on stomach mucosa were usually seen. The stomach microvilli appeared atrophic and disordered especially in the bodies of these earthworms growing in seriously polluted soil, bad atrophic phenomena were seen not only on the stomach mucosa microvilli but also on the cilia of the intestinal mucosa which appeared swollen as a spheroid. Under TEM, RER and Golgi compound dilatation, chondrisome swell and ridge disappearance were observed on cells of stomach epithelium mucosa of \%P.robusta\% collected from heavy polluted area. By calculation, the safety concentration of earthworm in methamidophos pesticide is 0\^2517 ml/L.展开更多
A laboratory incubation experiment was conducted to study the effect of chlorsulfuron herbicide on the size of the microbial in loamy sand soil. The herbicide was applied, at four levels that were control, field rate ...A laboratory incubation experiment was conducted to study the effect of chlorsulfuron herbicide on the size of the microbial in loamy sand soil. The herbicide was applied, at four levels that were control, field rate 0\^01 (FR), 0\^1 (10FR) and 1 (100FR) μg/g. Determinations of microbial biomass C content and microbial biomass N content were carried out 1, 3, 5, 7, 10, 15, 25 and 45 days after herbicide application. In comparison to untreated soil, the microbial biomass carbon and biomass nitrogen decreased significantly in soil treated with herbicide in levels 10FR and 100FR within the first 10 days incubation. A more considerable increase in the microbial biomass C∶N ratio was observed in the herbicide treated soil than the non treated control. This effect was transitory and only at the higher rates of chlorsulfuron was significant.展开更多
A solid phase extraction procedure of methomyl and thiodicarb from environmental water was presented. This method utilizes a 40—60 mesh activated carbon cartridge and high performance liquid chromatography (HPLC). Th...A solid phase extraction procedure of methomyl and thiodicarb from environmental water was presented. This method utilizes a 40—60 mesh activated carbon cartridge and high performance liquid chromatography (HPLC). The 40—60 mesh activated carbon works faster and yield higher adsorption efficiency. Detection limits of methomyl and thiodicarb in environmental water are 0 1 μg/L and 0 2 μg/L, respectively. Average recoveries of fortified methomyl and thiodicarb in water are in the range of 90 7%—98 8% and 88 9%—103 6%, respectively. The relative standard deviations are lower than 7%. This method is simple, rapid, accurate and precise.展开更多
A laboratory incubation experiment was conducted to elucidate the effect of chlorsulfuron herbicide on nitrogen mineralization and the ratio of microbial biomass nitrogen to nitrogen mineralization (N mic /N mi...A laboratory incubation experiment was conducted to elucidate the effect of chlorsulfuron herbicide on nitrogen mineralization and the ratio of microbial biomass nitrogen to nitrogen mineralization (N mic /N min ratio) in loamy sand soil.The herbicide was applied at four levels that were control, field rate 0\^01 (FR), 10 times of field rate 0\^1(10FR),and 100 times of field rate 1\^0 (100FR) μg/g soil. Determinations of N\|mineralization and microbial biomass\|N content were carried out 1,3,5,7,10,15,25 and 45 days after herbicide application. In comparison to untreated soil, the N\|mineralization decreased significantly in soil treated with herbicide at levels 10FR and 100FR within the first 5 days incubation. A more considerable reduction in the N mic /N min ratio was observed in the herbicide treated soil than the non\|treated control.Among the different treatment of chlorsulfuron, 100FR displayed the greatest biocidal effect followed by 10FR and FR,showing their relative toxicity in the order of 100FR>100FR>FR.The results indicated that the side effect of this herbicide on N\|mineralization is probably of little ecological significance.展开更多
文摘This paper studied the change in soil animal community in contaminated and irrigated area by organophosphorus pesticide waste water and its mechanism was discussed. The results showed that the species and quantities of soil animals decreased with organophosphorus pesticide pollution degree increasing. The species of soil animals decreased with average and rare population mainly decreasing, while the amount change was associated with that of the dominant population of Acarina, Collembola and Nematoda. Toxicity experiment demonstrated that the respiration intensity of soil animal was restrained obviously by pesticide pollution. After observation of SEM, the effect of pesticide pollution on the earthworm (\%Pheretima robusta)\% stomach intestinal mucosa damage has been observed, which showed the pesticide contamination may damage the earthworms bodies. Ulcerous focus and perforation on stomach mucosa were usually seen. The stomach microvilli appeared atrophic and disordered especially in the bodies of these earthworms growing in seriously polluted soil, bad atrophic phenomena were seen not only on the stomach mucosa microvilli but also on the cilia of the intestinal mucosa which appeared swollen as a spheroid. Under TEM, RER and Golgi compound dilatation, chondrisome swell and ridge disappearance were observed on cells of stomach epithelium mucosa of \%P.robusta\% collected from heavy polluted area. By calculation, the safety concentration of earthworm in methamidophos pesticide is 0\^2517 ml/L.
文摘A laboratory incubation experiment was conducted to study the effect of chlorsulfuron herbicide on the size of the microbial in loamy sand soil. The herbicide was applied, at four levels that were control, field rate 0\^01 (FR), 0\^1 (10FR) and 1 (100FR) μg/g. Determinations of microbial biomass C content and microbial biomass N content were carried out 1, 3, 5, 7, 10, 15, 25 and 45 days after herbicide application. In comparison to untreated soil, the microbial biomass carbon and biomass nitrogen decreased significantly in soil treated with herbicide in levels 10FR and 100FR within the first 10 days incubation. A more considerable increase in the microbial biomass C∶N ratio was observed in the herbicide treated soil than the non treated control. This effect was transitory and only at the higher rates of chlorsulfuron was significant.
文摘A solid phase extraction procedure of methomyl and thiodicarb from environmental water was presented. This method utilizes a 40—60 mesh activated carbon cartridge and high performance liquid chromatography (HPLC). The 40—60 mesh activated carbon works faster and yield higher adsorption efficiency. Detection limits of methomyl and thiodicarb in environmental water are 0 1 μg/L and 0 2 μg/L, respectively. Average recoveries of fortified methomyl and thiodicarb in water are in the range of 90 7%—98 8% and 88 9%—103 6%, respectively. The relative standard deviations are lower than 7%. This method is simple, rapid, accurate and precise.
文摘A laboratory incubation experiment was conducted to elucidate the effect of chlorsulfuron herbicide on nitrogen mineralization and the ratio of microbial biomass nitrogen to nitrogen mineralization (N mic /N min ratio) in loamy sand soil.The herbicide was applied at four levels that were control, field rate 0\^01 (FR), 10 times of field rate 0\^1(10FR),and 100 times of field rate 1\^0 (100FR) μg/g soil. Determinations of N\|mineralization and microbial biomass\|N content were carried out 1,3,5,7,10,15,25 and 45 days after herbicide application. In comparison to untreated soil, the N\|mineralization decreased significantly in soil treated with herbicide at levels 10FR and 100FR within the first 5 days incubation. A more considerable reduction in the N mic /N min ratio was observed in the herbicide treated soil than the non\|treated control.Among the different treatment of chlorsulfuron, 100FR displayed the greatest biocidal effect followed by 10FR and FR,showing their relative toxicity in the order of 100FR>100FR>FR.The results indicated that the side effect of this herbicide on N\|mineralization is probably of little ecological significance.
