Changes in the heavy metal and nutrient contents of dried feather mosses during long-term storage

This study measured heavy metal and nutrient concentrations of two feather mosses during the periods of dry storage. Samples (Hylocomium splendens, Pleurozium schreberi) were collected in the nationwide moss surveys carried out on the permanent sample plots of the 8th Finnish National Forest Inventory in 1985–86, 1990, 1995 and 2000. A small amount of each moss sample was analyzed soon after collection, and the remainder was dried and stored at the Paljakka environmental specimen bank (ESB). The 108 stored samples from 27 plots were reanalyzed in 2008. Concentrations of heavy metals (Cd, Cr, Cu, Fe, Ni, Pb, Zn) and nutrients (Ca, K, Mg, P) were determined and compared for each survey year. Overall, Fe, Pb and Cr concentrations decreased, and Cu concentrations increased significantly during storage. The greatest decrease was observed in samples from plots where their initial concentrations were the highest. Changes in the concentrations of Cd, Ni and Zn were less pronounced. The loss of heavy metals is likely due to drying when cell membranes rupture and some of the surface material is lost. K, P and, to some extent, Mg concentrations increased during storage, whereas Ca did not change significantly. Nutrient increase is probably due to their movement from older to younger growths during the initial phase of drying. Ca is mostly bound to cell walls and is not easily released. Results emphasize the importance of establishing the intended use of a stored moss prior to sampling, in order to select and optimize an appropriate storage technique.     

Impact of Climate Change on Fish Population Dynamics in the Baltic Sea: A Dynamical Downscaling Investigation

Understanding how climate change, exploitation and eutrophication will affect populations and ecosystems of the Baltic Sea can be facilitated with models which realistically combine these forcings into common frameworks. Here, we evaluate sensitivity of fish recruitment and population dynamics to past and future environmental forcings provided by three ocean-biogeochemical models of the Baltic Sea. Modeled temperature explained nearly as much variability in reproductive success of sprat (Sprattus sprattus; Clupeidae) as measured temperatures during 1973-2005, and both the spawner biomass and the temperature have influenced recruitment for at least 50 years. The three Baltic Sea models estimate relatively similar developments (increases) in biomass and fishery yield during twenty-first century climate change (ca. 28 % range among models). However, this uncertainty is exceeded by the one associated with the fish population model, and by the source of global climate data used by regional models. Knowledge of processes and biases could reduce these uncertainties.     

Closing a Loop: Substance Flow Analysis of Nitrogen and Phosphorus in the Rainbow Trout Production and Domestic Consumption System in Finland

Ongoing eutrophication is changing the Baltic Sea ecosystem. Aquaculture causes relatively small-scale nutrient emissions, but local environmental impact may be considerable. We used substance flow analysis (SFA) to identify and quantify the most significant flows and stocks of nitrogen (N) and phosphorus (P) related to rainbow trout aquaculture in Finland. In 2004–2007, the input of nutrients to the system in the form of fish feed was 829 t N year⁻¹ and 115 t P year⁻¹. Around one-fifth of these nutrients ended up as food for human consumption. Of the primary input, 70% ended up in the Baltic Sea, directly from aquaculture and indirectly through waste management. The nutrient cycle could be closed partially by using local fish instead of imported fish in rainbow trout feed, thus reducing the net load of N and P to a fraction.     

Use of decision analysis interviews to support the sustainable use of the forests in Finnish Upper Lapland

Controversy between alternative uses of forests in Finnish Upper Lapland has been going on for decades, and in recent years it has been escalated to a serious conflict. The core of the conflict is the adverse impacts of forestry on old forests which are important grazing areas for reindeer and which are regarded as intact nature and wilderness areas. This paper describes the experiences of applying multi-criteria decision analysis interview approach on this conflict. The approach provides tools for structuring the problem and preferences of the stakeholders as well as for analyzing the effects of different alternatives in a common framework. We focus on the practical experiences gained from the application of this approach in this context. Multi-criteria decision analysis was found to be a useful approach to evaluate the economic, ecological and cultural aspects of this intense conflict. The obtained experiences also support the view that the approach works best when tightly integrated into the planning process.     

PCB contamination from polysulphide sealants in residential areas-exposure and risk assessment

From the late 1950s to the early 1970s elastic polysulphide sealants were used in outdoor seams between concrete blocks in prefabricated buildings. The sealants contained 5-30% polychlorinated biphenyls (PCBs). Due to the weathering of sealants in general and the replacement of seams with new PCB-free materials in the 1990s, PCBs have drifted to the soil adjacent to buildings. The objectives of this study were to survey PCB contamination in the surroundings of former PCB-containing buildings and to evaluate the risks to human health. Samples from soil, and also from blood serum of residents, were collected to obtain data for exposure assessment. The health risk assessment was based on deterministic and probabilistic calculations for cancer and non-cancer risks. Soil ingestion and dermal contact were considered the main routes of exposure and children the most important exposed group. The mean total PCB concentration was 6.83 mg/kg within 2m of the buildings and 0.52 mg/kg within 3-10 m from of the buildings. The deterministic risk assessment with conservative parameters resulted in lifetime cancer risk estimates on the order of 10(-6)-10(-7). The lifetime average daily dose (LADD) for PCBs was less than 10% of the reference dose (RfD) 0.02 microg/kg day, which is based on immunosupression in monkeys. The LADD corresponding to the total site attributable exposure was less than 10% of the estimated average dietary PCB intake in Finland. Children can, however, in worst cases be exposed to daily doses near the level of the RfD. Low cost measures are recommended to reduce possible exposure of children.     

Current levels of DDT,PCB and trace elements in the Baltic ringed seals (Phoca hispida baltica) and grey seals (Halichoerus grypus)

Residue levels of polychlorinated biphenyls (PCBs) and 1,1,1-trichloro-2,2-bis[p-chlorophenyl]ethane (DDT) were determined from liver samples of ringed seals (Phoca lispida) from the Baltic Sea and Svalbard, and of grey seals (Halichoerus grypus) from the Baltic Sea and Sable Island in Canada. Both Baltic seal populations showed clearly higher average sum PCB (SPCB) and sum DDT (SDDT) levels than the reference seal populations. Among the Baltic seals, SPCB levels were twice as high as SDDT levels, and both contaminants were higher in ringed seals than in grey seals. A difference in gender was observed only in the Sable Island grey seal population, in which males showed a higher level of contamination than females. A reduction of the SDDT levels, and to a lower extent of the SPCB levels can be observed in the Baltic seals since the peak contaminant levels during the 1970s. The decrease has been more rapid in the grey seals than in the ringed seals. The SPCB levels in the Baltic ringed seals are still high enough to cause a threat to their well being. Residue levels of the trace elements mercury, cadmium, lead and selenium were determined from liver, kidney and muscle samples of grey seals from the Baltic Sea and Sable Island. Only cadmium showed a geographic difference being higher in the seals from Sable Island than from the Baltic Sea. No clear reduction of the metal burden can be observed in the Baltic grey seal population since the 1970s.     

Effect of catchment land use and soil type on the concentration,quality, and bacterial degradation of riverine dissolved organic matter

We studied the effects of catchment characteristics (soil type and land use) on the concentration and quality of dissolved organic matter (DOM) in river water and on the bacterial degradation of terrestrial DOM. The share of organic soil was the strongest predictor of high concentrations of dissolved organic carbon, nitrogen, and phosphorus (DOC, DON, and DOP, respectively), and was linked to DOM quality. Soil type was more important than land use in determining the concentration and quality of riverine DOM. On average, 5–9 % of the DOC and 45 % of the DON were degraded by the bacterial communities within 2–3 months. Simultaneously, the proportion of humic-like compounds in the DOM pool increased. Bioavailable DON accounted for approximately one-third of the total bioavailable dissolved nitrogen, and thus, terrestrial DON can markedly contribute to the coastal plankton dynamics and support the heterotrophic food web.     

Combining Conservation Value,Vulnerability, and Effectiveness of Mitigation Actions in Spatial Conservation Decisions: An Application to Coastal Oil Spill Combating

Increasing oil transportation and severe oil accidents in the past have led to the development of various sensitivity maps in different countries all over the world. Often, however, the areas presented on the maps are far too large to be safeguarded with the available oil combating equipment and prioritization is required to decide which areas must be safeguarded. While oil booms can be applied to safeguard populations from a drifting oil slick, decision making on the spatial allocation of oil combating capacity is extremely difficult due to the lack of time, resources and knowledge. Since the operational decision makers usually are not ecologists, a useful decision support tool including ecological knowledge must be readily comprehensible and easy to use. We present an index-based method that can be used to make decisions concerning which populations of natural organisms should primarily be safeguarded from a floating oil slick with oil booms. The indices take into account the relative exposure, mortality and recovery potential of populations, the conservation value of species and populations, and the effectiveness of oil booms to safeguard different species. The method has been implemented in a mapping software that can be used in the Gulf of Finland (Baltic Sea) for operational oil combating. It could also be utilized in other similar conservation decisions where species with varying vulnerability, conservational value, and benefits received from the management actions need to be prioritized.     

Cadmium and chromium in human lung tissue in relation to smoking and lung cancer

The pulmonary Cd and Cr content was determined from 53 lung cancer patients operated for cancer and from 39 patients who died of non‐malignant diseases. The results were correlated with smoking habits, pulmonary emphysema and occupational history. Both the pulmonary Cd and Cr increased with the amount of smoking. In ex‐smokers the Cr content in lung tissue did not diminish with the time since stopping smoking, but the Cd did follow the half‐life of about 9 years. The pulmonary Cd, compared with smoking habits, behaved similarly in both the lung cancer and control patients, whereas Cr in the lung cancer patients could not be explained solely by smoking, but some of the cancer patients may have been occupationally exposed to Cr. Speciation was not studied.