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81.
In this commentary, we respond to a report of the EFSA GMO Panel (EFSA EFSA Supp Publ, 1) that criticises the outcomes of two studies published in this journal (Hofmann et al. Environ Sci Eur 26: 24, 2; Environ Sci Eur 28: 14, 3). Both publications relate to the environmental risk assessment and management of Bt-maize, including maize events MON810, Bt11 and maize 1507. The results of Hofmann et al. (Environ Sci Eur 26: 24, 2), using standardised pollen mass filter deposition measurements, indicated that the EFSA Panel model had underestimated pollen deposition and, hence, exposure of non-target organisms to Bt-maize pollen. The results implied a need for safety buffer distances in the kilometre range for protected nature reserve areas instead of the 20–30 m range recommended by the EFSA Panel. As a result, the EFSA Panel revised their model (EFSA EFSA J 13: 4127, 4), adopting the slope of the empirical data from Hofmann et al. The intercept, however, was substantially reduced to less than 1% at one point by introducing further assumptions based on the estimates of mainly panel members, citing possible ‘uncertainty’. Hofmann et al. (Environ Sci Eur 28: 14, 3) published extensive empirical data regarding pollen deposition on leaves. These results were part of a larger 3-year study involving detailed measurements of pollen release, dispersal and deposition over the maize flowering period. The data collected in situ confirmed the previous predictions of Hofmann et al. (Environ Sci Eur 26: 24, 2). Mean levels and observed variability of pollen deposition on maize and four lepidopteran host plants exceeded the assumptions and disagreed with the conclusions of the EFSA Panel. The EFSA Panel reacted in a report (EFSA EFSA Supp Publ, 1) criticising the methods and outcomes of the two published studies of Hofmann et al. while reaffirming their original recommendations. We respond here point-by-point, showing that the critique is not justified. Based on our results on Urtica leaf pollen density, we confirm the need for specific environmental impact assessments for Bt-maize cultivation with respect to protected habitats within isolation buffer distances in the kilometre range.  相似文献   
82.
We introduce an approach for establishing reference conditions (RC) for rivers of the German Baltic Sea catchment, based on predictive modelling. An extensive data set of statistics from the year 1880 was coupled with literature data, providing a comprehensive basis for the calculation of regional historical nutrient emissions into rivers, river nutrient concentrations, and nutrient loading into the sea. Four different scenarios were calculated: scenario 1 assumed RC following previously established criteria for lakes (Poikane et al. in Environ Manag 45(6):1286–1298, 2010), scenario 4 applied the nutrient emission conditions of 1880 (considering non-intensive land usage, the presence of tile drainage systems, sewer systems, and the human population from 1880), and scenarios 2 and 3 considered intermediate conditions. Our results showed that nutrient emissions from scenario 1 accounted for approximately one-tenth of the currently observed total nitrogen (TN) and total phosphorus (TP) emissions. The nutrient emissions calculated for 1880 (scenario 4) were found to be 47 % (TN) and 55 % (TP) higher than those calculated considering reference lake conditions (scenario 1). Our results suggest that RC nutrient concentrations in rivers in the German Baltic Sea catchment were clearly below 0.05 mg/l for TP and 1 mg/l for TN. This range is in accordance with historical and calculated pristine nutrient concentrations from other rivers in similar catchments.  相似文献   
83.
The characterization of contaminated sites can benefit from the supplementation of direct investigations with a set of less invasive and more extensive measurements. A combination of geophysical methods and direct push techniques for contaminated land characterization has been proposed within the EU FP7 project ModelPROBE and the affiliated project SoilCAM. In this paper, we present results of the investigations conducted at the Trecate field site (NW Italy), which was affected in 1994 by crude oil contamination. The less invasive investigations include ground-penetrating radar (GPR), electrical resistivity tomography (ERT), and electromagnetic induction (EMI) surveys, together with direct push sampling and soil electrical conductivity (EC) logs. Many of the geophysical measurements were conducted in time-lapse mode in order to separate static and dynamic signals, the latter being linked to strong seasonal changes in water table elevations. The main challenge was to extract significant geophysical signals linked to contamination from the mix of geological and hydrological signals present at the site. The most significant aspects of this characterization are: (a) the geometrical link between the distribution of contamination and the site’s heterogeneity, with particular regard to the presence of less permeable layers, as evidenced by the extensive surface geophysical measurements; and (b) the link between contamination and specific geophysical signals, particularly evident from cross-hole measurements. The extensive work conducted at the Trecate site shows how a combination of direct (e.g., chemical) and indirect (e.g., geophysical) investigations can lead to a comprehensive and solid understanding of a contaminated site’s mechanisms.  相似文献   
84.
Although the foam formation on surface waters nowadays is not comparable with the foam “mountains” in the 1970s, it still is an issue of water quality concern. A drawback in the discussion is the lack of methods to assess instream foam formation and foam emitted by point sources. Foam formation on a transboundary river in Austria led to an intensive study resulting in two parameters to quantify instream and emitted foam. Foam potential is introduced as emission parameter that is defined as flow rate of river water, which can foam due to an effluent’s discharge. The foam index (FI) represents a parameter to assess the foam on the river and allows a semi-quantitative differentiation between the varying foaming conditions. This publication will present the developed methods and show some results to prove their accuracy and applicability.  相似文献   
85.
What motives do companies have to make a voluntary contribution to the protection and conservation of ecosystems? Could an international market for protected area certificates (PACs)—issued for geographical areas managed in accordance with social and environmental best practices—boost private investment? What are the market opportunities and risks that influence private sector investment? These questions are evaluated based on semi-structured expert interviews conducted in 39 German companies. Triangulation is used for data analysis to combine the advantages of qualitative and quantitative methods. Qualitative interview results complemented with the exploratory factor analysis allow identifying five motives for private sector investment, of which three are key motives in the early stage of developing PACs: direct financial benefits; the social legitimacy of entrepreneurial business; and the corporate dependency on ecosystems. Opportunities for private companies arise from the high marketing potential of certificates, the international orientation of the PAC market, and the bundling of different ecosystem benefits. Identified risks include a lack of differentiation, additional costs, and green washing. Depending on the transparency of the certification scheme, companies are aware that PACs could both improve and damage their credibility and reputation.  相似文献   
86.
The contamination of soils with pollutants by human activities has increased over a period of some decades. Deposited pollutants are immobilized in different ways depending on their chemical properties, or they are biologically available. This potential hazard requires a permanent control. An extensive investigation of topsoil in the surroundings of the fertilizer factory at Dorndorf-Steudnitz (Thuringia) was carried out to assess the size and extension of contamination and to estimate the potential risk which originates from the deposited pollutants. The fertilizer factory at Dorndorf-Steudnitz was one of the biggest dust emission sources in the middle part of the Saale river valley. Considerable damages of vegetation could be noticed already in the seventies and eighties. The trees and other plants in the neighbourhood of the factory died. The loadings of the investigated area may be attributed to a direct influence of gaseous and also of dustlike pollutants on the vegetation and resorption from the soil. Frequently, the content of pollutants in soils varies considerably. For this reason a univariate statistical evaluation of the data is not usually adequate. The use of geostatistical methods permits the characterization of the spatial structure of the investigated area and the undistorted assessment of the pollutant contents at unsampled points. The degree and extension of the contamination can be determined on the basis of the kriging estimation. The classification of analyzed features in regard to common sources of contamination can be realized by means of methods of multivariate data analysis.  相似文献   
87.
To explore the value of high-frequency monitoring to characterise and explain riverine nutrient concentration dynamics, total phosphorus (TP), reactive phosphorus (RP), ammonium (NH4-N) and nitrate (NO3-N) concentrations were measured hourly over a 2-year period in the Duck River, in north-western Tasmania, Australia, draining a 369-km2 mixed land use catchment area. River discharge was observed at the same location and frequency, spanning a wide range of hydrological conditions. Nutrient concentrations changed rapidly and were higher than previously observed. Maximum nutrient concentrations were 2,577 μg L?1 TP, 1,572 μg L?1 RP, 972 μg L?1 NH4-N and 1,983 μg L?1 NO3-N, respectively. Different nutrient response patterns were evident at seasonal, individual event and diurnal time scales—patterns that had gone largely undetected in previous less frequent water quality sampling. Interpretation of these patterns in terms of nutrient source availability, mobilisation and delivery to the stream allowed the development of a conceptual model of catchment nutrient dynamics. Functional stages of nutrient release were identified for the Duck River catchment and were supported by a cluster analysis which confirmed the similarities and differences in nutrient responses caused by the sequence of hydrologic events: (1) a build-up of nutrients during periods with low hydrologic activity, (2) flushing of readily available nutrient sources at the onset of the high flow period, followed by (3) a switch from transport to supply limitation, (4) the accessibility of new nutrient sources with increasing catchment wetness and hydrologic connectivity and (5) high nutrient spikes occurring when new sources become available that are easily mobilised with quickly re-established hydrologic connectivity. Diurnal variations that could be influenced by riverine processes and/or localised point sources were also identified as part of stage (1) and during late recession of some of the winter high flow events. Illustrated by examples from the Duck River study, we demonstrate that the use of high-frequency monitoring to identify and characterise functional stages of catchment nutrient release is a constructive approach for informing and supporting catchment management and future nutrient monitoring strategies.  相似文献   
88.
In the last decades the European Union exerted influence on precautionary environmental planning by the establishment of several Directives. The most relevant were the Habitat-Directive, the EIA-Directive, the SEA-Directive and the Water Framework Directive. Comparing these EU policies in the area of environmental precaution it becomes obvious that there is a lot of common ground. Thus, the conclusion seems likely that the European Union, in doing so, has intended to establish general planning concepts through introducing several methodological steps indicated by the regulations. The goal of this article is firstly to point out, which are the common planning principles, converted by methodological elements and secondly examine the consideration of these planning concepts by the implementation and application in the member states. In this context it is analysed whether the connections and divergences between the directives lead to significant differences in the implementation process. To this aim the directives are shortly introduced and significant steps of the processes regulated by them are outlined. In the second steps the national legal implementation in the Alpine states and its consequences for the practical application are discussed. The results show a heterogeneous application of the EU principles. Within the comparative view on the four directives influence and causalities between the national implementation and the practical application were identified, which can be simplified as four types. Since a coherent strategic and methodological concept for improving environmental precaution planning from part of the EU is noticeable, more unity and comparability within the implementation is desirable, particularly in areas with comparable habitats such as the alpine space. Beyond this the trade-off between the directives poses an important task for the future.  相似文献   
89.
The concept of ecosystem services is increasingly being used by scientists and policy makers. However, most studies in this area have focussed on factors that regulate ecosystem functions (i.e. the potential to deliver ecosystem services) or the supply of ecosystem services. In contrast, demand for ecosystem services (i.e. the needs of beneficiaries) or understanding of the concept and the relative ranking of different ecosystem services by beneficiaries has received limited attention. The aim of this study was to identify in three European mountain regions the ecosystem services of grassland that different stakeholders identify (which ecosystem services for whom), the relative rankings of these ecosystem services, and how stakeholders perceive the provision of these ecosystem services to be related to agricultural activities. We found differences: (1) between farmers?? perceptions of ecosystem services across regions and (2) within regions, between knowledge of ecosystem services gained by regional experts through education and farmers?? local field-based knowledge. Nevertheless, we identified a common set of ecosystem services that were considered important by stakeholders across the three regions, including soil stability, water quantity and quality, forage quality, conservation of botanical diversity, aesthetics and recreation (for regional experts), and forage quantity and aesthetic (for local farmers). We observed two contrasting stakeholder representations of the effects of agricultural management on ecosystem services delivery, one negative and the other positive (considering low to medium management intensity). These representations were determined by stakeholders?? perceptions of the relationships between soil fertility and biodiversity. Overall, differences in perceptions highlighted in this study show that practitioners, policy makers and researchers should be more explicit in their uses of the ecosystem services concept in order to be correctly understood and to foster improved communication among stakeholders.  相似文献   
90.
Background, aim and scope In 2007, the German government approved a national strategy on biological diversity. The strategy requires the integration of its quality targets and action targets into other policies. In addition to other pressure factors, area-wide diffuse substance discharges contribute considerably to the loss of biological diversity. Reducing these diffuse substance discharges to long-term ecologically compatible levels is one of the main action targets. This paper aims to provide an overview of preconditions for implementing this objective in terms of content as well as organization and to point out important deficits. Main focus To achieve this, the paper will discuss environmental monitoring and its implementation in Germany drawing on the targets of the national strategy on biological diversity. It will discuss the opportunities for the evaluation of the German and European biodiversity strategies using monitoring required in the execution of environmental laws and regulations as well as international substance-related indicators. Results Environmental monitoring in Germany and in Europe is characterized by a plurality of monitoring networks operated under different administrative competences and environmental sectors. Only a small part of the collected data is evaluated in a cross-media and cross-sectoral perspective even though the linking of the different data sets is technically possible. Discussion A key problem is that harmonized minimum requirements to monitor the reduction of diffuse substance discharges are missing. Without the implementation of a cooperative and harmonized monitoring approach and organizational guidelines, the reduction of diffuse substance discharges will not be verifiable. Environmental data as well as indicators are essential to evaluate the success of the national biodiversity strategy. Suitable monitoring concepts are available in the German Federal Republic and its Federal States, nevertheless, a political impulse for their implementation is missing. Recommendations and perspectives The national biodiversity strategy may reopen the discussion on the necessity of an integrated monitoring. A coordinated approach that refers both to the international indicator-discussion and to institutional obstacles and aims to develop a proposal for integrated monitoring data is necessary.  相似文献   
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