Density-dependent migratory waves in the marine pelagic ecosystem

The migration of large aggregations of animals that sweep through the landscape is a phenomenon with large consequences in many ecosystems. It has been suggested that such migrations are mediated by resource depletion. Under this hypothesis it has been shown that simple foraging rules may generate density-dependent migratory waves (DDMW) in which the speed and amplitude increase with animal abundance. We tested these predictions on a 32-year data set of the spatial distribution of the two youngest age groups of a small pelagic schooling fish, the capelin (Mallotus villosus), by the end of their annual feeding migration in the Barents Sea. Our data suggest that the two age groups divided the Barents Sea by forming migratory waves that moved in opposite directions. The aggregation and spatial displacement of these waves increased with increasing age-specific abundance. However, possibly through social interactions, migratory pattern was modified by the abundance of the other age group.     

Modelling changes in forest soil chemistry at 16 Swedish coniferous forest sites following deposition reduction

The dynamic forest ecosystem model ForSAFE was applied at 16 coniferous forest sites in Sweden to investigate past and future changes in soil chemistry following changes in atmospheric deposition. The simulation shows a considerable historical soil acidification. Acidification in the southwest, where deposition has been greatest, was more expressed in the deepest soil layers, while it was more evenly distributed through the soil profile in central Sweden, and was greater in the upper soil layers in the north. The simulation also shows that a slight recovery took place after the reduction in emissions, but was counteracted by the effect of harvesting. The simulation predicts an increase in the number of acidified sites in the future. The results also suggest that future acidification will be mainly due to the enhanced tree growth resulting from the chronic high deposition of nitrogen and the removal of soil base cations through harvesting.     

Politikberatung in der Wissensgesellschaft

Zusammenfassung  In diesem Artikel werden einige zentrale Ergebnisse einer Untersuchung zur wissenschaftlichen Politikberatung dargestellt. Nach einer kurzen Einführung in das Konzept der ‘pluralistischen Wissensgesellschaft’ wird die Analyse-Perspektive erl?utert und das Untersuchungsdesign skizziert. Anhand einer Vergleichsstudie zu umweltpolitischen Beratungssystemen wird dann aufgezeigt, wie die Beratungspraxis aussieht. Schlie?lich werden Gestaltungsoptionen diskutiert. Siehe UWSF 12 (6) 350 (2000) Schlagw?rter: Politikberatung: umweltpolitische Beratung     

Importance of climate uncertainty for projections of forest ecosystem services

Regional Environmental Change - Mountain forests provide a wide range of ecosystem services (ES, e.g., timber production, protection from natural hazards, maintaining biodiversity) and are...     

Prospects for stakeholder coordination by protected‐area managers in Europe

Growing resource demands by humans, invasive species, natural hazards, and a changing climate have created broad‐scale impacts and the need for broader‐extent conservation activities that span ownerships and even political borders. Implementing regional‐scale conservation brings great challenges, and learning how to overcome these challenges is essential for maintaining biodiversity (i.e., richness and evenness of biological communities) and ecosystem functions and services across scales and borders in the face of system change. We administered an online survey to examine factors potentially driving perspectives of protected‐area (PA) managers regarding coordination with neighboring PAs and other stakeholders (i.e., stakeholder coordination) for conserving biodiversity and ecosystem services during the next decade within diverse regions across Europe. Although >70% (n = 58) of responding PA managers indicated that climate change and invasive species are relevant for their PAs, they gave <50% probability that these threats could be mitigated through stakeholder coordination. They thought there was a >60% probability (n = 85) that stakeholder coordination would take place with the aim to improve conservation outcomes. Consistent with the foundation on which many European PAs were established, managers viewed maintaining or enhancing biodiversity as the most important (>70%; n = 61) expected benefit. Other benefits included maintaining or enhancing human resources and environmental education (range of Bayesian credibility intervals [CIs] 57–93%). They thought the main barriers to stakeholder coordination were the lack of human and economic resources (CI 59–67% chance of hindering; n = 64) followed by communication and interstakeholder differences in political structures and laws (CI 51–64% probability of hindering). European policies and strategies that address these hindering factors could be particularly effective means of enabling implementation of green infrastructure networks in which PAs are the nodes.     

Modelling spatial patterns of correlations between concentrations of heavy metals in mosses and atmospheric deposition in 2010 across Europe

Background

This paper aims to investigate the correlations between the concentrations of nine heavy metals in moss and atmospheric deposition within ecological land classes covering Europe. Additionally, it is examined to what extent the statistical relations are affected by the land use around the moss sampling sites. Based on moss data collected in 2010/2011 throughout Europe and data on total atmospheric deposition modelled by two chemical transport models (EMEP MSC-E, LOTOS-EUROS), correlation coefficients between concentrations of heavy metals in moss and in modelled atmospheric deposition were specified for spatial subsamples defined by ecological land classes of Europe (ELCE) as a spatial reference system. Linear discriminant analysis (LDA) and logistic regression (LR) were then used to separate moss sampling sites regarding their contribution to the strength of correlation considering the areal percentage of urban, agricultural and forestry land use around the sampling location. After verification LDA models by LR, LDA models were used to transform spatial information on the land use to maps of potential correlation levels, applicable for future network planning in the European Moss Survey.

Results

Correlations between concentrations of heavy metals in moss and in modelled atmospheric deposition were found to be specific for elements and ELCE units. Land use around the sampling sites mainly influences the correlation level. Small radiuses around the sampling sites examined (5 km) are more relevant for Cd, Cu, Ni, and Zn, while the areal percentage of urban and agricultural land use within large radiuses (75–100 km) is more relevant for As, Cr, Hg, Pb, and V. Most valid LDA models pattern with error rates of <?40% were found for As, Cr, Cu, Hg, Pb, and V. Land use-dependent predictions of spatial patterns split up Europe into investigation areas revealing potentially high (=?above-average) or low (=?below-average) correlation coefficients.

Conclusions

LDA is an eligible method identifying and ranking boundary conditions of correlations between atmospheric deposition and respective concentrations of heavy metals in moss and related mapping considering the influence of the land use around moss sampling sites.

     

Method for the determination of sub-ppm concentrations of perfluoroalkylsulfonate anions in water

The determination of sub-ppm concentrations of aqueous perfluoroalkylsulfonate (PFSt) anions, including perfluorooctylsulfonate (PFOS), has been accomplished with a relatively simple mass spectrometric procedure that does not require extraction of the analytes into an organic solvent or a chromatographic separation prior to injection into the negative-ion electrospray ionization mass spectrometer. Sample pretreatment was minimized and consisted of dilution of the aqueous samples of groundwater, surface water, tap water, and distilled water with acetonitrile, addition of dodecylsulfate (DDS) as an internal standard, and, in some cases, addition of known amounts of perfluorobutylsulfonate (PFBS) or PFOS for standard-addition experiments. The linear-response range for PFOS is 25.0 microg L(-1) to 2.5 mg L(-1). The lower limit of this range is three orders of magnitude lower than an equally straightforward chromatographic method. The relative errors for standard aqueous solutions containing only 25.0 microg L(-1) and 2.5 mg L(-1) PFOS are +/- 14% and +/- 7%, respectively, with 133 microg L(-1) DDS as the internal standard. The detection limit and quantification limit for PFOS in these standards are 5.0 microg L(-1) and 25.0 microg L(-1), respectively. Six different PFS anions, containing three to eight carbon atoms, were identified and quantified in an aqueous film-forming foam (AFFF) formulation using the method of standard additions. Two alkylsulfate anions and two perfluoroalkylcarboxylate anions were also identified in the AFFF formulation.     

利用不同形态硫同位素组成辨识土壤污染过程的方法初探

本研究利用硫含量变化特征和不同形态硫同位素组成的变化规律,分析土壤硫源和迁移转化过程,辨识土壤污染过程.在北京市首钢烧结厂和通州永乐店分别采集了2条土壤剖面.研究结果显示：首钢工业区土壤硫含量在0.01%和0.69%间变化,土壤全硫在0.001%和0.03%间变化;工业区附近土壤样品可溶性硫酸盐硫同位素组成、硫化物硫同...