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微生物降解有机磷农药残留机理及菌种筛选研究进展 总被引:11,自引:0,他引:11
农药的使用一方面可以保证农业稳产和增产,另一方面却改变了土壤微环境,污染周边的水体乃至大气环境。在农药使用造成的各种污染中,农药残留对人类影响大,作用时间长,尤其是部分有机磷农药具有高毒、降解慢的特点,污染人类生存环境,危害人体健康。使用微生物降解农药残留是解决该问题的有效方法。本文对微生物降解有机磷农药残留的机理和微生物诱变和筛选的最新进展进行总结,并对农药残留降解微生物的发展方向提出了自己的观点。 相似文献
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农药残留及微生物在农药降解中的应用与展望 总被引:14,自引:0,他引:14
农药在人类防治农作物病虫害、草害等诸方面起到了巨大的贡献,但是因之而来的农药残留问题则对环境和人类健康带来了严重的危害。为解决这一问题,人们进行了大量的研究,其中微生物的降解作用已引起人们的广泛关注。综述了农药残留及微生物在其中的应用及发展情况。 相似文献
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浅谈有机杀虫剂的微生物降解 总被引:7,自引:0,他引:7
寻找,研究有机杀虫剂及其残留物的降解菌有益于环境保护,综述DDT等9种有机杀虫剂的降解微生物,其微生物降解农药的途径,及其应用现状和前景。 相似文献
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微生物农药在俄罗斯的应用进展 总被引:1,自引:0,他引:1
微生物农药因其副作用小、对环境兼容性好而日益成为全球农药发展的一种趋势和方向。本文以细菌杀虫剂、真菌杀虫剂、病毒杀虫剂、微生物除草剂、植物生长调节剂、农用抗生素作为微生物农药的代表,介绍了微生物农药的研究、应用现状及其在俄罗斯的研究进展,并对我国与俄罗斯在微生物农药领域的合作进行了展望。 相似文献
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化学农药在茶树上多种降解因子定量关系的研究 总被引:7,自引:0,他引:7
作者采用实验室模拟与田间试验相结合的方法,研究了光照、温度、水分和茶树生长等主要环境因子对氯氰菊酯、马拉硫磷在茶树上降解的影响及定量关系。结果表明,同种环境因子对不同类型农药在茶树上降解作用的差异很大。茶树新梢的生长稀释对田间残留期长的氯氰菊酯的降解起主导作用,可占田间总降解的60%;而挥发和热分解对残留期较短、蒸气压较高的马拉硫磷的降解起主导作用,在复季可占田间降解的50%。光解和水解对这两种农药在茶树上的降解也起着一定作用。此外,降雨、风和生物代谢等也不同程度地影响农药在茶树上的降解。 相似文献
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苦参碱的水解动态及其在自然水体中的降解特性 总被引:2,自引:2,他引:0
农药的降解特性是评价其环境安全性的重要指标。为评价植物源农药苦参碱对水环境的安全性,依据“化学农药环境安全性评价试验准则”,采用室内模拟试验探讨了苦参碱的水解动态及其在自然水体中的降解特性和影响因素。结果表明:苦参碱在不同pH值缓冲液中水解均较缓慢,120 d后水解率仍低于25%,属于难降解型;其在6种自然水体中降解均较快,半衰期在6.3~12.8 d之间,降解速率排序依次为池塘水河水雨水湖水海水自来水;在6种自然水体中(25℃±1℃),苦参碱降解速率随其初始浓度的升高而减慢,半衰期与初始浓度呈正相关,但均小于30 d,属于易降解型。比对试验表明:微生物是影响苦参碱降解速率的主要因素,水体中微生物的量与其降解半衰期呈显著负相关关系(P=0.006)。可见,苦参碱在自然水体中易降解,该特性对于指导苦参碱的实际应用具有重要意义。 相似文献
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几种农药在露地黄瓜上的残留降解动态检测研究 总被引:2,自引:0,他引:2
研究了在露地黄瓜栽培中。喷施毒死蜱、甲氰菊酯、氯氰菊酯、吡虫啉、百菌清、甲基硫菌灵和王铜等农药的残留降解动态。结果表明,不同农药在黄瓜果实中的残留量和降解速度有很大差异。在杀虫剂中.甲氰菊酯在喷药后第1d的残留量最大,其后的降解速度较快;毒死蜱残留量位居第二,其降解速度比较稳定;氯氰菊酯在喷药后第1d的残留量超过标准.但第3d以后就检测不到其残留:吡虫啉在施药后第1d的残留量最低,降解速度也比较稳定。在杀菌剂中.甲基硫菌灵的降解速度较快,百菌清和王铜的降解速度较慢。无论是杀虫剂还是杀菌剂,施药后在黄瓜上的残留量随喷药时间的推移而减少。 相似文献
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残留的五种有机磷农药在菜豆烹饪过程中的降解 总被引:5,自引:0,他引:5
采用气相色谱法检测了久效磷、毒死蜱、马拉硫磷、对硫磷、敌敌畏5种有机磷农药在菜豆烹饪过程中残留量的变化。结果表明:菜豆经油炸后,除久效磷未降解外,其余农药降解率在37.6%~85.1%之间。油炸时间的长短对敌敌畏降解影响较大,炸5 min时降解率为37.6%,7 min 时降解率为65.2%;油炸时间长短对其余农药的降解均无显著影响。炒的过程中5种农药的降解率在7.6%~56.5%之间;蒸的过程中降解率为23.0%~63.4%;未盖锅盖煮的条件下降解率为39.5%~81.7%,盖锅盖煮后降解率为42.0%~86.4%。在加盖煮10 min后的汤中,各种农药的残留量在0.03~0.50 mg/L 之间。炒过的菜豆再经微波加热2 min后, 5种农药残留量比炒过之后又降解了21.0%~41.5%。 相似文献
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研究了小白菜栽培过程中,百菌清、敌敌畏、氧化乐果和抗蚜威在不同施用剂量条件下的农药降解动态规律,结果表明,不同农药在小白菜中的残留量和降解速度有较大差异。4种农药施药后在小白菜上的残留量随喷药时间的推移而减少,抗蚜威降解速度最慢,氧化乐果降解速度最快。 相似文献
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The degradation, sorption and transport of atrazine, hexazinone and procymidone in saturated coastal sand aquifer media were investigated in batch and column experiments. The pesticides were incubated with sterilised and non-sterilised groundwater or a mixture of groundwater and the aquifer material in the dark at 15 degrees C for 120 days. The estimated half-lives of the pesticides (and their ranges) in the mixture of groundwater and aquifer sand were 36 (31-40), 54 (40-77) and 84 (46-260) days for atrazine, procymidone and hexazinone, respectively. Compared with the relevant results for the groundwater-sand mixture phase, the estimated half-life of pesticides in the groundwater phase alone was shorter for procymidone (21 days) but longer for hexazinone (134 days); atrazine was not degraded in the groundwater phase. Chemical degradation appeared to have played the predominant role in the degradation of hexazinone and procymidone in the aquifer system, while both chemical and biological processes seemed to be important for the degradation of atrazine. Batch isothermal experiments were carried out at pH 4.6-4.7 to obtain sorption coefficients under equilibrium conditions. The isothermal data of the pesticides fitted well with the non-linear Freundlich function with an exponent of sorption coefficient that was greater than one. Contrary to reports in the literature, sorption of atrazine was the greatest, and procymidone was slightly more sorbed than hexazinone. A column experiment was conducted at a typical field-flow velocity of 0.5 m day(-1) over 60 days to study pesticide attenuation and transport in flow dynamic conditions. Retardation factors, R, derived from a two-site sorption/desorption model were 8.22, 1.76 and 1.63 for atrazine, procymidone and hexazinone, respectively. Atrazine displayed the lowest mobility and the mobility of procymidone was only slightly less than that of hexazinone, which is consistent with observations in the batch experiment. A possible explanation for these observations is that ionic atrazine is bound to oppositely charged ionic oxides, and ionic oxides have less effect on the sorption of the non-ionic procymidone. The significant tailing in the pesticide breakthrough curves (BTCs) in comparison with the bromide BTC, together with model-simulated results, suggests that the transport of the pesticides was under chemical non-equilibrium conditions with R values that were less than their equivalent values predicted using the batch equilibrium isothermal data. As a result of non-linear kinetic sorption, retardation factors of the pesticides in groundwater systems would not be constant and will decrease with decreasing pesticide concentrations and increasing flow velocities. Hence, the use of equilibrium isotherm data will probably over-predict the sorption of pesticides in groundwater systems. Rhodamine WT, a commonly used groundwater tracer, was significantly retarded (R = 5.48) and its BTC was much more spread out than the bromide BTC. Therefore, it would not be a good tracer for the indication of groundwater flow velocity and dispersion for the coastal sand aquifer system. In contrast to some aquifer media, the dye tracer was unsuitable as a marker of the appearance of atrazine in a coastal sand aquifer system. 相似文献
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美国登记注册的生物农药主要分为生物化学农药和微生物类农药,其中生物化学农药包括引诱剂、驱避剂、天然昆虫/植物生长调节剂及除草剂、信息素、其他生化农药等;微生物类农药包括细菌、真菌、病毒、酵母、原生动物、工程菌、转基因植物等。 相似文献
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A field tracer experiment, simulating point source contamination, was conducted to investigate attenuation and transport of atrazine, hexazinone and procymidone in a volcanic pumice sand aquifer. Preliminary laboratory incubation tests were also carried out to determine degradation rates. Field transport of the pesticides was observed to be significant under non‐equilibrium conditions. Therefore, a two‐region/two‐site non‐equilibrium transport model, N3DADE, was used for analysis of the field data. A lump reduction rate constant was used in this paper to encompass all the irreversible reduction processes (eg degradation, irreversible adsorption, complexation and filtration for the pesticides adsorbed into particles and colloids) which are assumed to follow a first‐order rate law. Results from the field experiment suggest that (a) hexazinone was the most mobile (retardation factor R = 1.4) and underwent least mass reduction; (b) procymidone was the least mobile (R = 9.26) and underwent the greatest mass reduction; (c) the mobility of atrazine (R = 4.45) was similar to that of rhodamine WT (R = 4.10). Hence, rhodamine WT can be used to delimit the appearance of atrazine in pumice sand groundwater. Results from the incubation tests suggest that (a) hexazinone was degraded only in the mixture of groundwater and aquifer material (degradation rate constant = 4.36 × 10?3 day?1); (b) procymidone was degraded not only in the mixture of groundwater and aquifer material (rate constant = 1.12 × 10?2 day?1) but also in the groundwater alone (rate constant = 2.79 × 10?2 day?1); (c) atrazine was not degraded over 57 days incubation in either the mixture of aquifer material and groundwater or the groundwater alone. Degradation rates measured in the batch tests were much lower than the total reduction rates. This suggests that not only degradation but also other irreversible processes are important in attenuating pesticides under field conditions. Hence, the use of laboratory‐determined degradation rates could underestimate reduction of pesticides in field conditions. © 2001 Society of Chemical Industry 相似文献
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