波罗的海蓝藻赤潮的历史

波罗的海所发生的赤湖,主要是由Nodudaria spupmigena和Aphanizomenon sp.这两种蓝藻形成的.有关这些赤潮的长期变化记录可以从过去(1887～1938年)和现代(1974～1998年)出版的浮游植物数据记录中找到.通过各种不同的收集、分析方法已经得到了大量的数据,为了提高这些数据的可比性,人们正在不断地尝试老的、新的采样方式与固定方法.l00多年前,浮游生物就做为鱼类的食物来源而引起了人们的兴趣;富营养化问题主要出现在南部的礁湖(haffs)以及大城市附近的海边水ro域.二战前,很少有关于开阔海域赤潮的报道.在过去的营养环境中,Nodudaria spupmlgena和Aphanizomenon sp.的数量还很少,从l 887～1938年的137个夏季采样中表明它们的丰度还没有达到过最高峰.在现在的营养环境中,高丰度是非常普遍的,这两个物种的数目范围相对于过去的营养环境来说有了明显的增长.自20世纪60年代以来,蓝藻赤潮在波罗的海本体与芬兰湾的开阔海域是非常常见的,这表明了营养物已经高度丰富.     

Fragmentation of Landscape as a Cause for Genetic Subdivision in Bank Voles

Abstract: We studied the barrier effects of various roadways on the genetic subdivision of bank vole (Clethrionomys glareolus) populations. Allele frequencies, genetic variability, and genetic distances of natural populations were calculated based on polymorphism of seven microsatellite markers. We compared bank vole populations in control areas without such barriers with animals from both sides of a country road, a railway, and a highway. Using F and R statistics, we demonstrated significant population subdivision in bank vole populations separated by the highway, but not in populations on either side of the other roadways or in the control area. Correlations between geographic and genetic distances were revealed by an extended method based on a Mantel analysis. This allowed us to measure genetic barrier effects and express them as additional geographic distances. For instance, statistically significant differences in allele frequencies in all seven loci examined existed among populations in southern Germany and Switzerland, which are separated by the Rhine River and Lake Constance. The real geographic distance between bank vole populations in Konstanz and those in Lengwil, Switzerland, was 6 km. According to this analysis the genetic barrier effect of the Rhine could be defined as an additional distance of 7.7 km. This study shows for the first time that not only old geographic barriers but also more recent fragmentation of landscape by, for example, highways has an important effect on gene flow and the genetic substructuring of populations, which should be considered in future environmental impact assessments.     

Risk management—the Swedish way(s)

We have compared three legal and administrative systems of risk management in Sweden, namely those responsible for work environment, environmental protection and chemicals control. Large differences were found in terms of the organisational structure and the general modi operandi of government activities in the three areas. Many of these differences seem to be the result not of deliberate choice, but rather of the lack of coordination between policy areas. One of the most striking differences is the much lower priority assigned to enforcement activities in the environmental than in the occupational health sector. It is concluded that systematic comparisons of experiences from different policy areas can be helpful in improving the efficiency of risk management.     

Whole cell hybridisation for monitoring harmful marine microalgae

Fluorescence in situ hybridisation (FISH) is a powerful molecular biological tool to detect and enumerate harmful microorganism in the marine environment. Different FISH methods are available, and especially in combination with automated counting techniques, the potential for a routine monitoring of harmful marine microalgae is attainable. Various oligonucleotide probes are developed for detecting harmful microalgae. However, FISH-based methods are not yet regularly included in monitoring programmes tracking the presence of harmful marine microalgae. A limitation factor of the FISH technique is the currently available number of suited fluorochromes attached to the FISH probes to detect various harmful species in one environmental sample at a time. However, coupled automated techniques, like flow cytometry or solid-phase cytometry, can facilitate the analysis of numerous field samples and help to overcome this drawback. A great benefit of FISH in contrast to other molecular biological detection methods for harmful marine microalgae is the direct visualisation of the hybridised target cells, which are not permitted in cell free formats, like DNA depending analysis methods. Therefore, an additional validation of the FISH-generated results is simultaneously given.     

Entwicklung von Prüfwertempfehlungen für ausgewählte Schadstoffe zum Schutz des Bodens als Lebensraum für Bodenorganismen

Goal and Scope

In the German Federal Soil Protection and Contaminated Sites Ordinance there are no ecotoxicological trigger values for the protection of soil as a habitat for soil organisms. The objective of this study was to derive preliminary trigger values for the habitat function of soils. This was done by collecting data on the impact of priority pollutants on soil organisms and plants followed by the parallel use of the Factorial Application Method (FAME) and Distribution Based Extrapolation (DIBAEX) and a final verification of the plausibility of the calculated trigger values by means of an ecotoxicological test battery.

Methods

Data on the effects of pollutants on soil organisms and plants were recorded in a specific data base (Soil Value). Subsequently, we derived so-called ‘working trigger values’ using the extrapolation methods FAME (factorial application method) and DIBAEX (distribution based extrapolation). In the second phase of the project, we verified experimentally the plausibility of these values by means of an ecotoxicological test battery. Test substrate was a sandy soil with low sorption capacity and organic carbon content which was mixed with fresh pollutants (e.g. heavy metal salts) and polluted soil material from contaminated sites (aged contamination), respectively. Organisms tested were microorganisms, plants, earthworms, springtails and nematodes.

Results and Conclusions

We calculated working trigger values for 12 pollutants based on 900 datasets compiled in he data base. The laboratory investigations showed the freshly added contaminants to be less strongly adsorbed to the soil than those added by the use of contaminated soil material. Nevertheless, aged contaminations displayed often the same inhibitive effects as the freshly added chemicals. The results achieved in the second phase of the project were also recorded in the Soil-Value database. Based on the new data set, final trigger values were derived for the experimentally tested substances.

Outlook

The procedure described in this contribution exemplarily for copper can be used for the derivation of recommended trigger values for the pathway soil ? soil organisms. Besides copper, preliminary trigger values were derived for zinc, mercury, lead and HCH.     

Food 21: a research program looking for measures and tools to increase food chain sustainability

Food 21, an interdisciplinary research program encompassing the whole agro-food chain, was conducted in Sweden during 1997-2004. The challenges undertaken were to come up with environmental tools and solutions to existing nonsustainable practices along the entire food chain. This required close collaboration between the scientists and the food chain stakeholders. A set of goals characterizing sustainable food production is presented in this paper. Synthesis and systems analysis were the main tools used to analyze the sustainability of proposed changes. In this introduction we give an overview of the Food 21 concept and highlight some results. For example, we found that organic farming and organic products were not in general superior to conventional products and practices with respect to environmental impact and product quality. We also summarize the management experiences in this article, since we consider them to be rather unique and since they contributed to the overall success of the program.     

Dynamic multi-resolution spatial models

Data from remote-sensing platforms play an important role in monitoring environmental processes, such as the distribution of stratospheric ozone. Remote-sense data are typically spatial, temporal, and massive. Existing prediction methods such as kriging are computationally infeasible. The multi-resolution spatial model (MRSM) captures nonstationary spatial dependence and produces fast optimal estimates using a change-of-resolution Kalman filter. However, past data can provide valuable information about the current status of the process being investigated. In this article, we incorporate the temporal dependence into the process by developing a dynamic MRSM. An application of the dynamic MRSM to a month of daily total column ozone data is presented, and on a given day the results of posterior inference are compared to those for the spatial-only MRSM. It is apparent that there are advantages to using the dynamic MRSM in regions where data are missing, such as when a whole swath of satellite data is missing.     

Gull eggs--food of high organic pollutant content?

A wide range and occasionally high levels of persistent organic pollutants (POPs) are reported in Arctic regions, especially among top predators. Polar bears (Ursus maritimus), arctic foxes (Alopex lagopus) and some gull species (Larus spp.) often have high levels of these fat-soluble pollutants. Gulls deposit significant levels of these contaminants in their eggs. In northern regions, gull eggs are part of the traditional human diet. In the present study we have investigated the levels of POPs in gull eggs in order to determine the tolerable weekly intake (TWI) for humans. Concentrations of polychlorinated biphenyls (PCBs), polychlorinated dibenzo-p-dioxins (PCDDs) and polychlorinated dibenzofurans (PCDFs) were measured in 214 gull eggs collected in the spring of 2001-02. The eggs were collected from four gull species (herring gulls (Larus argentatus), great black-backed gulls (L. marinus), lesser black-backed gulls (L. fuscus) and glaucous gulls (L. hyperboreus)) at 12 different locations in Northern Norway, on the Faroe Islands and on Svalbard. The pollutant levels in gull eggs were found to be 65.5 +/- 26.9 pg toxic equivalent (TE) for dioxin and PCB g(-1) wet weight. Based on these findings and the TWI-value determined by the EU Scientific Committee on Food it is advised that children, young women and pregnant and nursing women should not eat gull eggs. Other people should limit their intake of eggs to an absolute minimum, considering the health risks associated with gull egg intake.