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11.
This study describes the governance and management structures of the Curonian Spit World Heritage Site, a transboundary protected area shared by Lithuania and the Russian Federation. Focusing on the national park authorities it presents the site from a local administrative perspective. The paper shows that due to strong state level influence and a lack of full stakeholder inclusion, different philosophies and priorities on both sides of the border challenge common management efforts and co-operation. Presenting the existing problems the paper points out the need for increased efforts at the state level as well as for the full inclusion of local communities to remove obstacles and foster co-operation. Hence, by adapting to certain environmental and transboundary governance principles, conflicts can be avoided and better results achieved.  相似文献   
12.
Air samples collected in the German part of the North Sea from March to July 2010 were investigated for organophosphorus compounds (OPs) being applied as flame retardants and plasticizers. The ∑8OPs concentration ranged from 110 to 1400 pg m−3 while tris(2-chloroisopropyl) phosphate (TCPP) dominated all samples with individual concentrations up to 1200 pg m−3. The highest concentrations were observed in continental air masses showing the high influence of industrialized regions including production sites on atmospheric emissions and concentrations. The occurrence of OPs even in oceanic/Arctic air masses shows that OPs can undergo long-range atmospheric transport. Dry particle-bound deposition fluxes from 9 to 240 ng m−2 d−1 for ∑8OPs were estimated leading to a minimum annual flux of 710 ± 580 kg y−1 OPs into the German North Sea. This study presents the first occurrence of OPs in the marine atmosphere together with important information on their long-range transport potential.  相似文献   
13.
Dechlorane Plus (DP) has been determined in surface sediments from three Chinese coastal bays, e.g. Jiaozhou, Sishili and Taozi Bay in North China. DP concentrations ranged from <1.2 to 187 pg g−1 dry weight (dw) (mean: 24.7 pg g−1 dw) in Jiaozhou Bay, <1.2 to 135 pg g−1 dw (mean 69.9 pg g−1 dw) in Sishili Bay and <1.2 to 66.7 pg g−1 dw (mean: 40.4 pg g−1 dw) in Taozi Bay, respectively. Additionally, two dechlorinated species were quantified, which accounted for 0.6-5.1% of the ∑DP concentration.The fsyn values (syn-isomer/(syn- + anti-isomer)) in sediments from Jiaozhou Bay (mean 0.29) were close to the technical DP mixture (0.2-0.4), probably indicating local inputs of DP. In contrast, sediments in Sishili and Taozi Bay showed much lower fsyn values (mean 0.16). During transportation the DP isomers are subject to stereo selective degradation which partly resulted in the relative enrichment of anti-DP in coastal sediments.  相似文献   
14.
This paper develops a method for identifying and assessing long-term supply risks for mineral raw materials. The method is based on a combined evaluation of past and future supply and demand trends. By analysing raw material boom and bust cycles over the past 50 years, we have quantified indicators and defined benchmarks for identifying critical market situations. By applying the method, risks for supply shortage may be identified at an early stage. In addition, a numerical evaluation model has been developed for better comparison between various mineral raw materials. Compared to other assessment methods this method uses specific benchmarks for each raw material to better assess supply risks. The method is embedded within a systematic and comprehensive analytical approach.  相似文献   
15.
This paper examines the identity of Asian swamp buffalo (Bubalus bubalis) from different value orientations. Buffalo were introduced into Northern (Top End) Australia in the early nineteenth century. A team of transdisciplinary researchers, including an ethicist, has been engaged in field research on feral buffalo in Arnhem Land over the past three years. Using historical documents, literature review, field observations, interviews with key informants, and interaction with the Indigenous land owners, an understanding of the diverse views on the scientific, cultural, and economic significance of buffalo was obtained. While the diverse stakeholders in buffalo exploitation and management have historically delivered divergent value orientations on the nature of the human–buffalo relationship, we argue that over time there is the possibility of values and ethical convergence. Such convergence is possible via transdisciplinary and transcultural agreement on the value stances that constitute the construction of the being or identity of buffalo in the face of the overwhelming need to manage population density and gross numbers.  相似文献   
16.
Ozonation as final wastewater (WW) polishing step, following conventional activated sludge treatment is increasingly implemented in sewage treatment for contaminant degradation to prevent surface water pollution. While the oxidative degradation of chemicals has been extensively investigated, the in vivo toxicological characteristics of ozonated whole effluents are rarely a matter of research.In the present study, whole effluents were toxicologically evaluated with an in vivo test battery before and after full-scale ozonation and subsequent sand filtration on site at a treatment plant. One aquatic plant (duckweed, Lemna minor) and five invertebrate species of different systematic groups (Lumbriculus variegatus, Chironomus riparius, Potamopyrgus antipodarum, Daphnia magna) were exposed to the effluents in a flow-through-designed test system with a test duration of 7-28 d.None of the considered toxicity endpoints correlated with the pollutant elimination. A tendency towards an increased toxicity after ozonation was apparent in three of the test systems showing [statistically] significant adverse effects in the L. variegatus toxicity test (decrease in reproduction and biomass). After sand filtration, adverse effects were reduced to a similar level like after conventional treatment. Solely the Daphnia reproduction test revealed beneficial effects after ozonation in combination with sand filtration.Results of the test battery indicate the formation of adverse oxidation products during WW ozonation. L. variegatus appeared to be the most sensitive of the five test species. Sand filtration effectively removes or detoxifies toxic oxidation products, as toxic effects were subsequently reduced to the level after conventional treatment.  相似文献   
17.
We address the global deficit of data describing kelp forest distribution, relative covers and biomass by testing the ability of species distribution models to predict these attributes at locations where data are currently limited. We integrated biological ground truth data with high-resolution environmental datasets to develop generalized additive models that accurately predict the structure of Laminaria forests within the Bay of Morlaix (48°42′42″N, 3°55′40″W). Forest distribution and proportional covers were predicted using water depth, light availability, wave exposure and sediment dynamics. The biomass of individual kelp species was modeled by supplementing these same variables with measures of seafloor slope and benthic position. Biomass predictions for Laminaria digitata and Laminaria hyperborea contrast the physiological tolerances of these species to light and wave exposure gradients. As a direct management output, we produced high-resolution maps (25 m2 grids) that closely match independent field data and provide vital information for marine spatial planning.  相似文献   
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Wax perception in honeybees: contact is not necessary   总被引:1,自引:0,他引:1  
In social insects, much progress has been made in identifying variations in the cuticular signatures of sexes, castes, kin and reproductive status. In contrast to this, we still do not know how the receivers perceive these recognition cues. This study was designed to investigate whether honeybees use contact-chemosensory or olfactory sensilla to perceive wax components. To answer this question in a behavioral assay, we combined classical conditioning of the proboscis extension reaction and a recently established method using zinc sulfate to selectively block antennal contact-chemosensory sensilla. Comparison of the responses to sucrose, wax and geraniol before and after antennal zinc sulfate treatment revealed that the sucrose response is lost after treatment but the responses to wax and geraniol are maintained. As sucrose is perceived by the contact-chemosensory sensilla, the retention of the wax response indicates that contact-chemosensory sensilla are not necessary for wax perception.  相似文献   
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