Biomarker responses as indication of contaminant effects in blue mussel (Mytilus edulis) and female eelpout (Zoarces viviparus) from the southwestern Baltic Sea

During a field study performed in spring and autumn 2001 and 2002, blue mussels (Mytilus edulis) and female eelpout (Zoarces viviparus) were collected at three locations in the Wismar Bay (Baltic Sea), and several biomarkers of contaminant effects were analysed. Besides seasonal and inter-annual variations, biomarker signals were most pronounced at the location closest to Wismar Harbour (Wendorf) in both species. Lysosomal membrane stability (LMS) was lowest and acetylcholinesterase activity (AChE) was significantly reduced. Frequency of micronuclei (MN) was significantly higher (in blue mussels), indicating mutagenic effects. In eelpout elevated levels of DNA adducts, EROD induction and PAH-metabolites were measured. Metallothionein (MT), biomarker for trace metal exposure, showed a gradient only in spring. Organochlorine contaminant analyses (PCBs, DDTs) corresponded to the observed biomarker levels. The results obtained clearly demonstrate pollution effects in the southwestern Baltic Sea. Moreover, they show that a multibiomarker approach is also applicable in a brackish water environment.     

ILWIS软件核心的最新发展

文章阐述了导致ILWIS当前版本发展方法论上的一些重要的考虑。主要设计变动在于处理多种地理参照领域的方式和系统的属性数据库，该数据库用了本机构研制的软件。文章还提出了如何使将来的ILWIS版本具备全面综合的地学数据库环境的新设计思想的见解。     

印度沿海地带咸水浸入的初步制图

整个世界的沿海地带都有咸水向沿岸淡水含水层浸透的现象。在农田很受重视的地区要求采取保护和预防性措施再强调也不可能过份。为识别和监视受影响地区的地面测量既费时又劳民伤财，有时还有危险。本研究对采用陆地卫星图像制作西印度沿海地图进行了初步的调查试验。虽然由于缺乏同期的地面测量数据，研究成果并不一定很确切，但是把历时１４多年的三个时间的卫星数据相比较说明了该方法对监视沿海地带土壤的盐碱化展是有用的。     

模糊集合论用于制图综合中地图物体选取结构模型的研究

地图物体选取的定额模型和结构模型对机助制图综合和地图数据库专家系统中是缺一不可的。结构模型是在选取定额数量的控制下,解决具体选取那些物体,而研究某物体的选取须考虑的因素甚多,並且其间关系是隐会的,普遍存在模糊性。因而采用传统的二值逻辑来处理会既麻烦又损失较多的制图信息。本文以河流选取为例,用模糊集合理论对其建立结构模型进行初步探讨,并用简单样图说明方法和步骤。     

Effects of heavy metals on the survival and feeding behaviour of the sandy shore scavenging gastropod Nassarius festivus (Powys)

The effects of Cu, Cd, Zn and Cr on the survival and feeding behaviour of the sandy shore scavenging gastropod Nassarius festivus were compared. The 96-h LC₅₀ for Cu, Cd, Zn and Cr were 0.36, 1.52, 1.76 and 36.9 mg l⁻¹, respectively. Four sublethal concentrations of each metal plus a control were prepared and the snails were exposed to experimental solutions for 96 h. Feeding behaviour was studied after the snails were starved for five days. As compared with the control, the number of individuals feeding was significantly reduced by exposure to 0.05 mg l⁻¹ Cu, 0.2 mg l⁻¹ Zn, 0.5 mg l⁻¹ Cd and 5 mg l⁻¹ Cr. The time spent feeding was greater for individuals exposed to greater concentrations of Zn and Cd but no effect was found for Cu and Cr. Chemoreception of food was studied by placing the snails at a fixed distance of 15 cm from the bait. The success rate of reaching the bait was less for individuals exposed to Cr but no effect was found for Zn, Cu or Cd. The time required for an individual to reach the bait decreased as the concentration of Zn increased. In contrast, a longer time was required for individuals exposed to Cr whereas the effect of Cd and Cu was insignificant. The potential of using feeding behaviour and chemoreception in contaminant evaluations is discussed.