Causes of phytotoxicity of metsulfuron-methyl bound residues in soil

The bioavailability and phytotoxicity of bound residues of metsulfuron-methyl were studied using 14C-labeling and bioassay with oil rape (Brassica napus L.). Soil bound residues at the concentration of 0.27 and 0.53 nmol g(-1) resulted in significant inhibition of oil rape seedling growth. The biologically active component of the bound residues was identified to be metsulfuron-methyl parent compound. Other metabolites, including the hydrolysis product 2-methylformate-benzenesulfonamide, showed no toxicity to the test species. This study suggests that residues of metsulfuron-methyl bound previously to the soil matrix could be again released upon planting. The phytotoxicity of metsulfuron-methyl bound residues was mainly caused by the metsulfuron-methyl parent compound that became available during plant growth.     

杭州市郊菜区大气及蔬菜中氟化物的含量和分布

本文分析调查了杭州市郊菜区大气及一些主要蔬菜中氟化物的含量及分布，并对蔬菜中氟化物含量与大气氟污染的关系进行了相关分析。结果表明，杭州市郊菜区个别蔬菜中氟化物含量已超过有关标准，这主要与工业污染源的分布有关；蔬菜中氟化物含量与大气氟浓度之间存在着明显的相关关系。     

长链烷烃降解菌alkB片段的分离和鉴定

分离并鉴定了长链烷烃降解菌Pseudomonasaeruginosa1785和P.marginata766烃羟化酶基因alkB片段.根据烃羟化酶的保守氨基酸序列,设计兼并引物,扩增P.aeruginosa1785和P.marginata766的alkB片段,获得了目标产物.经DNA测序和氨基酸序列分析,证实目标片段编码的肽段含有烃羟化酶的特征基序.由此确认采用该方法分离到了长链烷烃降解基因的alkB同源体片段.DNA序列比对结果表明,P.aeruginosa1785和P.marginata766的alkB片段与P.aeruginosaPAO1的alkB1和alkB2的相似性分别达到95.7%和94.8%.这些alkB片段可用于分析烃降解微生物群落结构.图3表2参11     

若尔盖湿地3种无尾两栖类不同发育阶段的生态位宽度

研究了若尔盖湿地国家级自然保护区的3种无尾两栖类,高原林蛙(Rana kukunoris)、倭蛙(Nanorana pleskei)和岷山蟾蜍(Bufo minshanicus)的成体和亚成体在7个生境因子(牧场性质、牛粪数量、植被高度、植被盖度、距水塘距离、地表温度、地表湿度)上的生态位宽度.结果表明,岷山蟾蜍成体在牧场性质、牛粪数量、植被盖度、地表温度、地表湿度5个维度上的生态位宽度最窄,其亚成体在牧场性质、牛粪数量、植被高度、距水塘距离、地表湿度5个维度上的生态位宽度最宽;倭蛙亚成体在牧场性质、牛粪数量、地表温度、地表湿度4个维度上的生态位宽度最窄,而其成体在牛粪数量、植被高度、植被盖度、距水塘距离4个维度上的生态位宽度最宽;高原林蛙在微气候因子的两个维度上具有较大的生态位宽度值,而在水塘距离维度上的生态位宽度值则很小.当人类活动导致生境变更时,倭蛙的反应最为敏感;比较3种无尾两栖类在不同生长阶段(成体、亚成体)的生态位宽度,发现它们利用资源的策略不同.表3参16     

长期继代培养马铃薯愈伤组织的植株再生

对影响马铃薯愈伤组织发生、生长和长期继代培养的愈伤组织再生植株的几种因素进行了研究。马铃薯茎段的愈伤组织发生频率高于叶片的愈伤组织发生频率。Ｄｉｃａｍｂａ诱导茎段和叶片的愈伤组织发生频率在９０％以上；而２，４－Ｄ的诱导效果不佳并诱发外植体生根。再生培养其中加入０．５ｇ／Ｌ的酶解酷蛋白是必需的；蔗糖的浓度以２％－４％为宜；附加ＺＴ２．０ｍｇ／Ｌ、ＧＡ０．１ｍｇ／Ｌ可使长期继代的愈伤组织的植株再生频率     

天然水中有机污染物的生物降解模拟实验方法

本文系统地介绍了天然水体中有机污染物生物降解实验室模拟的建立原则、方法和分类，并以有机污染物邻苯二甲酸二甲酯（ＤＭＰ）和二乙酯（ＤＥＰ）为例，介绍了生物降解模拟实验过程。     

高效液相色谱法分析水中痕量多环芳烃

本文利用高效液相色谱法测定水中痕量多环芳烃（ＰＡＨｓ）。以二氯甲烷作溶剂,超声提取水中痕量ＰＡＨｓ;甲醇、水作流动相,梯度淋洗,用程序可变波长荧光检测器测定。ＰＨＡｓ浓度为０．００７＝０．６μｇ·ｍｌ＾－１范围时,线性相关系数均在０．９９９９以上;峰高、峰面积的相对标准偏差（ｎ＝１０）分别为１．０１－１．８５％,２．００－３．９４％;检测限（Ｓ／Ｎ＝２）为３．１－２３．０ｐｇ;实际水样的加标回收率     

Acclimation of anaerobic sludge degrading chlorophenols and the biodegradation kinetics during acclimation period

The acclimation of sludge from Hangzhou citrate factory and Hangzhou municipal wastewater treatment plant for degradation dechlorination of chlorophenols (CPs) compounds, and its biodegradation kinetics were studied in batch process with or without addition of sucrose. Three monochlorophenols (2-CP; 3-CP; 4-CP) and pentachlorophenol (PCP) were concurrently fed to different bioreactors. The parameters that were monitored included biogas production, biogas composition and chemical oxygen demand (COD). The results showed that acclimation with chlorophenol can increase the degradation activity of anaerobic sludge and degradation rate of chlorophenolic compounds, and reduce the lag time. Degradation dechlorination activity of the acclimated sludge strongly depended on sludge source, microorganism population and chlorophenol congener. 2-CP was more easily acclimated than 3-CP and 4-CP. Among the four tested compounds, 4-CP was the most difficult to be acclimated. The observed degradation rate with presence of sucrose was higher than that with absence of sucrose, suggesting that addition of the external carbon source can stimulate the formation of acclimated sludge which could effectively degrade chlorophenols. Kinetic equations of biodegradation of chlorophenols were also presented in this paper.     

垃圾渗滤液物化处理研究

采用物化处理方法对垃圾渗滤液进行处理,反应时间为1 h,进水的pH为7,出水的pH调至12,澄清后的pH调节到7～8,试验结果表明,COD的浓度从7452 mg/L降低到67 mg/L,去除率达到99.1%;TN的浓度从1055 mg/L降低到637 mg/L,去除率达到40%;TP的浓度从13.2 mg/L降低到未检出,去除率达到100%;色度从2048倍降低到1倍;除TN以外,COD、TP和色度均可达到国家规定的排放标准.     

含莠去津和乙草胺河水灌溉对苗期水稻危害的研究

本文以１９８８、１９９２和１９９３年洋河流域张家口市部分水稻田污染受害事故为背景，通过事故现场调查资料分析、洋河水质监测、宣化区污染源调查、水稻的药害暴露实验和模型计算，研究了含有除草剂莠去津和乙草胺的河水灌溉对苗期水稻的危害。结果显示，河水中莠去津和乙草胺对水稻苗期的安全灌溉浓度分别为０．０１ｍｇ／Ｌ和０．０５ｍｇ／Ｌ；河水中莠去津对水稻的致死浓度是０．１ｍｇ／Ｌ；ｐＨ、ＮＨ３－Ｎ和表面活性剂对这种危害作用具有一定的协同效应；为了满足河水对水稻的灌溉水质要求，污染源允许排放的莠去津和乙草胺分别为１．０ｋｇ／ｄ和２．０ｋｇ／ｄ。