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311.
312.
Kai Ahrendt Horst Sterr Peter Krost Wilhelm Windhorst Michael Schultz 《Journal of Coastal Conservation》2018,22(1):115-130
Marine aquaculture is facing a variety of competing uses in densely populated coastal areas such as the coast of Kiel Bay. Thus, a major barrier for extending the marine aquaculture business could be the lack of suitable space for “offshore farming”. Moreover, in public opinion the aquaculture sector is often associated with a negative image derived from environmental concerns. It might therefore be expected that planning aquaculture installations in Kiel Bay & Fjord would face resistance both from other offshore stakeholders and the public. This study therefore addressed the question whether arguments and criteria can be found that may contribute to a greater support and positive image of local aquaculture enterprise, thus fostering political support for this sector as well. Indeed, a widespread regional survey showed less public reservation towards aqua-cultural business in Kiel Fjord than initially expected. However, expanding the entrepreneurship in the regional aqua-cultural sector will only be successful if the installations can avoid a significant deterioration of the water quality in Kiel Fjord, e.g. through excessive emissions of nutrients from net cages. An important step forward toward this goal is the concept of IMTA = Integrated Multi-Trophic Aquaculture. The IMTA concept spatially integrates nutrient emitting installations such as fish net cages with installations of nutrient extracting organisms, e.g. mussels and algae. Based on spatial analyses of marine environmental parameters and through modelling of nutrient mass balances (emitted versus extracted nutrient quantities) possible locations, types and sizes of aquaculture installations can be determined. 相似文献
313.
Wilhelm A. Kiwango Hans C. Komakech Thadeo M. C. Tarimo Lawrence Martz 《国际发展与全球生态学杂志》2018,25(3):238-248
Participatory approaches to conservation are viewed as a plausible alternative to the old ‘fortress conservation’ approach. The design and implementation of these approaches in developing countries have tended to embrace community participation through decentralized governance mechanisms in the past three decades. However, sustainable conservation approaches that maintain community livelihoods while conserving biodiversity are challenged with meeting both objectives. In addressing this challenge, little attention has been given to an empirical analysis of community’s satisfaction levels on how they participated in the design and implementation of this approach. In this article, we use a mixed method approach using both quantitative and qualitative data to examine levels of satisfaction and participation of local communities in the Idodi-Pawaga Wildlife Management Area (WMA), south-western Tanzania. We find that social economic factors (e.g. age, household size, gender, number of years living in the same location and participation/non-participation) influence, in different ways, the satisfaction levels of community’s participation towards the WMA creation. Due to inadequate participation, we find that the WMA design and implementation process failed from the beginning to actively involve the local communities and this has resulted in the near absence of the promised economic benefits from wildlife conservation. We suggest that participation should go beyond the simple information sharing to actively engage the local communities in key planning activities from the beginning of any WMA programme. It is also important to take into consideration their levels of satisfaction with the process of decision-making if meaningful decentralized governance is to be achieved. 相似文献
314.
We investigated the effects of two river restoration projects on hydromorphology and macroinvertebrate fauna in two German
lowland rivers, the Schwalm and the Gartroper Mühlenbach. The stream channels were re-meandered and the floodplain levels
were lowered to better connect the streams to their floodplains. The restoration was performed 10 years ago in the Schwalm
and 2 years ago in the Gartroper Mühlenbach. We compared the restored reaches to nearby anthropogenically straightened reaches.
Twenty-five hydromorphological parameters were recorded on twenty transects; between nine and 23 substrate-specific macroinvertebrate
samples were taken per reach. Several hydromorphological parameters, such as the number and width of channel features and
the number of substrate types, were significantly higher in the restored reaches compared to nearby anthropogenically straightened
reaches. Total numbers of invertebrate families, genera, and taxa were also higher in the restored reaches than in the anthropogenically
straightened reaches. Biotic substrates like dead wood or macrophytes were more abundant in the restored reaches, and these
substrates hosted 28 taxa not found in the straightened reaches. While diversity was high in both restored reaches, overall
abundance increased only in the river that was restored 10 years ago. Using NMS-analysis, substrate-specific faunistic samples
of the restored reaches were compared to those of the straightened reaches. Our results revealed different invertebrate communities
on the same substrates in the recently restored river. In the 10-year-old restoration, however, the same substrates were similarly
inhabited. This comparable colonization of substrates may reflect succession in the macroinvertebrate community. The results
are discussed according to the re-colonization potentials of the upstream and downstream reaches and the dispersal capacity
of taxa. 相似文献
315.
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317.
Wilhelm Von Sander 《Die Naturwissenschaften》1957,44(19):504-506
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319.
In the present study 83 finished drinking water samples from 50 cities in Germany were analyzed for methyl tert-butyl ether (MTBE) content with a detection limit of 10 ng/L. The detection frequency was 46% and the concentrations ranged between 17 and 712 ng/L. Highest concentrations were found in the community water systems (CWSs) of Leuna and Spergau in Saxony-Anhalt. These CWSs are supplied with water possibly affected by MTBE contaminated groundwater. MTBE was detected at concentrations lower than 100 ng/L in drinking water supplied by CWSs using bank filtered water from Rhine and Main Rivers. The results from Leuna and Spergau show that large groundwater contaminations in the vicinity of CWSs pose the highest risk for MTBE contamination in drinking water. CWSs using bank filtered water from Rhine and Main Rivers are susceptible to low MTBE contaminations in finished drinking water. All measured MTBE concentrations were below proposed limit values for drinking water. 相似文献
320.
Koch W Dunkhorst W Lödding H Thomassen Y Skaugset NP Nikano A Vincent J 《Journal of environmental monitoring : JEM》2002,4(5):657-662
The Respicon has been introduced as a sampler for health related measurements of airborne contaminants at workplaces. The instrument is aimed at simultaneous collection of three health related aerosol fractions: (a) the coarser inhalable fraction, defining the aerosol fraction that may enter the nose and mouth during breathing; (b) the intermediate thoracic fraction, defining the fraction that may penetrate beyond the larynx and so reach the lung; and (c) the finer respirable fraction, defining the fraction that may penetrate to gas exchange region of the lung. The instrument has a number of features attractive to occupational hygienists: in addition to providing the three aerosol fractions simultaneously, it is light and compact enough to be used as a personal sampler. yet can be a tripod mounted for area sampling, it can provide samples not only for gravimetric analysis but also microscopic and chemical analyses; and it is also available in a photometric direct-reading version. The instrument has previously been evaluated as an area sampler and, in this mode of operation, has shown reasonable accuracy in collecting respirable, thoracic and inhalable particles, the latter up to particle diameters of ca. 80 microm. Except for some scattered unpublished data there exist no systematic investigations in the Respicon's performance when used as a personal sampler in the industrial environment. In this paper, we will report on a study of side by side comparison of the Respicon with the IOM inhalable sampler, regarded as a reference instrument for the inhalable fraction. The main study was performed at six different workplaces in a nickel refinery. Statistical analysis of the gravimetrically-determined concentration data reveals consistently lower aerosol exposure values for the Respicon as compared to the IOM sampler. The data for the nickel workplaces are compared with findings from other studies. The results are interpreted in the light of the overall results and the possibility of introducing a correction factor is discussed. 相似文献