乙虫腈悬浮剂对新出房意大利蜜蜂的毒性研究

乙虫腈是在我国登记并广泛使用的氟虫腈替代药剂,其商品化制剂为拜尔公司研发的100 g·L~(-1)悬浮剂,目前关于乙虫腈制剂对非靶标生物的毒性研究少有报道。为探究乙虫腈制剂对蜜蜂的毒性作用,采用人工饲喂法分别测定了100 g·L~(-1)乙虫腈悬浮剂对新出房意大利蜜蜂的48 h急性和14 d慢性毒性作用。结果显示:乙虫腈悬浮剂对新出房意大利蜜蜂的48 hLC_(50)值为0.21 mg·L~(-1)(95%置信限0.16～0.26 mg·L~(-1)),相应的48 h-LD50为5.0×10~(-3)μg a.i.·蜂~(-1)(95%置信限1.0×10~(-3)～1.0×10~(-2)μg a.i.·蜂~(-1));在亚致死剂量下,蜜蜂死亡数量随暴露时间的延长而增多,且100 g·L~(-1)乙虫腈悬浮剂会引起蜜蜂显著的氧化应激反应,诱导抗氧化酶SOD和CAT活力、脂质过氧化产物MDA含量、解毒酶GST活力和底物GSH含量的显著变化。研究表明,乙虫腈悬浮剂对意大利蜜蜂毒性较高,即使在亚致死剂量下亦存在显著的影响。田间施用应防止药剂的漂移污染,并避免在作物花期施用;新出房意大利蜜蜂对药剂敏感,未来可探索其作为风险指示生物应用的可能。     

Interactive effects of single,binary and trinary trace metals (lead,zinc and copper) on the physiological responses of Kandelia obovata seedlings

Environmental Geochemistry and Health - Heavy metals are considered important environmental contaminants, and their mixture toxicity on plants has complex mutual interactions. The interactive...     

Distribution and assessment of mercury (Hg) in surface sediments of Futian mangrove forest,China

Environmental Geochemistry and Health - To investigate the distribution of mercury (Hg) in Futian mangrove wetland, surface sediments from land to sea were collected, including Kandelia obovata,...     

蚯蚓对垃圾与底泥中镉的富集现象

通过蚯蚓处理垃圾及纳污河流底泥实验研究发现蚯蚓可选择吸收并富集垃圾及底泥中的镉，但对其他重金属元素铅、铜、锌等并无此种富集吸收现象。     

生物降解途径的理论预测与QSBR研究

本文把有机污染生生物降解途径理论预测的结果与ＱＳＢＲ模型中化合物选择相结合，所遵循相同理论生物降解途径作为化合物分组的原则，以分子连接性接数和ＥＨＯＭＯ作为结构参数与电性参数，采用逐步回归的方法建立了新的ＱＳＢＲ模型，新模型的预测民实验结果能较好地吻合。     

知识经济时代的企业经营与管理

21世纪经济正向着知识经济时代迈进.知识经济不仅对人类的生产方式和生活方式产生着深远影响,而且对企业的经营方式和管理模式也将产生深远的影响.我国企业在知识经济时代下,如何转变和调整经营与管理方式己成为新世纪的重大课题.     

关于风景评价中心理物理学方法局限性的探讨

由于对西方风景评价理论和方法缺乏足够的了解和深入的研究，现今国内对其中的心理物理学方法及其作用产生了一些误解。本文在扼要介绍了心理物理学派的主要方法思路之后，着重对该学派所存在的重大理论缺陷和方法局限性做了较深入的分析。     

Propylene glycol vapor contamination in controlled environment growth chambers: toxicity to corn and soybean plants

A major, often unrecognized variable regulating plant growth in semi-closed environment is air contaminant. The vapor of propylene glycol (PG), which was used as coolant in growth chambers, has been found to be toxic to corn (Zea mays L.) and soybean (Glycine max L.) plants. PG solution leaked from a valve packing system and volatilized to vapor, which was trapped in a semi-closed growth chamber. Symptoms of leaf edge chlorosis, later developing into necrosis, were observed on the third day of emergence or on the third day after moving healthy plants into the chamber. For young soybean plants, symptoms were slightly different from those observed in corn plants; the chlorosis symptoms were not uniformly distributed on all leaves. Some soybean leaves curled up and others had white spots. This problem was identified by using a portable photoionization detector to obtain instantaneous readings of total volatile organic compound concentrations inside the chambers. The presence of PG in selected chambers was verified using sample collection with solid phase microextraction (SPME) followed by analysis with multi-dimensional gas chromatography mass spectrometry (MD-GC-MS). This information is pertinent to researchers who use controlled environment to grow plants.