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1.
Reservoirs have a wide variety of uses that have led to frequent conflicts over ecological conservation and contamination, especially as land management has intensified. Oligotrophication must be implemented in numerous tropical reservoirs that experience advanced eutrophication to maintain aquatic ecosystem functions. To quantify impacts on ecosystem functions and to develop an adaptive management policy, multiple studies have been conducted on the Itaparica Reservoir, São Francisco River, in the semi-arid north-eastern region of Brazil. Here, we add to that existing body of knowledge through investigating how nutrient accumulation is affected by water exchange between the main river flow and Icó-Mandantes Bay. Operational water-level fluctuations in the reservoir create large desiccated littoral areas that release high amounts of nutrients when they are rewetted. In particular, water-level variation promotes proliferation of Egeria densa, a noxious weed, thus elevating trophic levels of the Itaparica Reservoir and Icó-Mandantes Bay. Analysis with a P efficiency model determined 25 μg P L?1 to be the critical concentration and further indicated that the critical load in both bodies of water have been exceeded. Moreover, intensive fish aquaculture using net cages has led to further overtaxing of the reservoir. We conclude that an effective ecological reservoir management policy must involve oligotrophication, harvesting of noxious water weeds for use as soil amendment in agriculture or biogas production, “blue” aquaculture, and limiting hydroelectric power production based on current water availability.  相似文献   
2.

Participation is usually regarded as a good practice in environmental policymaking, but its effects on policy strategies are unclear. Based on literature research, surveys, and interviews with participants, the present paper assesses whether decisional participation in formulating Austria’s National Adaptation Strategy (NAS) was worth the effort. Assessed against the goals of the participation process, we find that it raised awareness for adaptation and facilitated an exchange among the participants and that it improved the content of the NAS. However, regarding the goal of enhancing the acceptance of and commitment to the NAS, we find that this has been achieved among those who participated but not among high-level policymakers who are responsible for implementing the NAS. We conclude that (decisional) participation has its benefits in formulating comprehensive policy strategies but that it is most likely not able to overhaul their well-documented weaknesses, among them weak political commitment and implementation failures.

  相似文献   
3.
The photocatalytic reduction of CO2 with H2O was investigated using Cu/TiO2 photocatalysts in aqueous solution. For this purpose, Cu/TiO2 photocatalysts (with 0.2, 0.9, 2, 4, and 6 wt.% of Cu) have been synthesized via sol-gel method. The photocatalysts were extensively characterized by means of inductively coupled plasma optical emission spectrometry (ICP-OES), N2 physisorption (BET), XRD, UV-vis DRS, FT-IR, Raman spectroscopy, TEM-EDX, and photoelectrochemical measurements. The as-prepared photocatalysts contain anatase as a major crystalline phase with a crystallite size around 13 nm. By increasing the amount of Cu, specific surface area and band gap energy decreased in addition to the formation of large agglomeration of CuO. Results revealed that the photocatalytic reduction of CO2 decreased in the presence of Cu/TiO2 in comparison to pure TiO2, which might be associated to the formation of CuO phase acting as a recombination center of generated electron-hole pair. Decreasing of photoactivity can also be connected with a very low position of conduction band of photocatalysts with high Cu content, which makes H2 production necessary for CO2 reduction more difficult.  相似文献   
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5.
This paper examines the legitimacy, viability and efficiency of the European Union Solidarity Fund by asking whether the Fund meets its stated purpose of providing solidarity within the EU, whether it is sufficiently capitalized and if it promotes disaster risk reduction in Europe. In examining these questions, we make use of ADAM models of disaster risks throughout Europe. We conclude that the Solidarity Fund falls short on all three counts, and we suggest possible alternatives. Most far-reaching, we explore whether the EUSF could support insurance systems in Europe by, among other possible activities, capitalizing national public-private insurance programs and providing support for government risk transfer. This would leverage the Fund’s capital and would overcome barriers to the provision of private and public sector insurance in uncertain catastrophe markets. It would also make insurance more affordable to Europe’s most vulnerable communities. Finally, it would reduce the disincentives for risk reduction inherent in post-disaster assistance.  相似文献   
6.
Despite the growing popularity of ecological restoration approach, data on primary succession on toxic post-mining substrates, under site environmental conditions which considerably differ from the surrounding environment, are still scarce. Here, we studied the spontaneous vegetation development on an unusual locality created by long-term and large-scale fluvial deposition of sulphidic tailings from a copper mine in a pronouncedly xerothermic, calcareous surrounding. We performed multivariate analyses of soil samples (20 physical and chemical parameters) and vegetation samples (floristic and structural parameters in three types of occurring forests), collected along the pollution gradients throughout the affected floodplain. The nature can cope with two types of imposed constraints: (a) excessive Cu concentrations and (b) very low pH, combined with nutrient deficiency. The former will still allow convergence to the original vegetation, while the latter will result in novel, depauperate assemblages of species typical for cooler and moister climate. Our results for the first time demonstrate that with the increasing severity of environmental filtering, the relative importance of the surrounding vegetation for primary succession strongly decreases.  相似文献   
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8.
Diclofenac, a non-steroidal anti-inflammatory drug (NSAID), has caused catastrophic vulture declines across the Indian sub-continent. Here, an indirect ELISA is used to detect and quantify diclofenac in 1251 liver samples from livestock carcasses collected across India between August 2007 and June 2008, one to two years after a ban on diclofenac manufacture and distribution for veterinary use was implemented. The ELISAs applicability was authenticated with independent data obtained using LC-ESI/MS. Of 1251 samples, 1150 (91.9%) were negative for diclofenac using both methods, and 60 (4.8%) were positive at 10-4348 and 10-4441 μg kg(-1) when analysed by ELISA and LC-ESI/MS, respectively. The residue level relationship in the 60 positive samples was highly significant (p < 0.001, r(2) = 0.644). Data suggest that this immunological assay could be used not only for cost effective sample screening, but also for residue level semi-quantification.  相似文献   
9.
Diesel particulate matter poses a threat to human health, and in particular nitrated polycyclic aromatic hydrocarbons (NPAHs) found within and on the surface of these particles. Although diesel particulate filters (DPFs) have been designed and implemented to reduce these and other harmful diesel emissions, the particle loaded filters may act as a reaction chamber for the enhanced production of NPAHs from the nitration of PAHs with NO2.Focus is on the investigation of the heterogeneous reactions that occur on soot particles by exposing laboratory produced pyrene- or benzo(a)pyrene-coated spark discharge soot particles to varying concentrations of NO2 and temperatures while following the formation of products over time. The sole nitration product that was observed throughout the experiments with pyrene-coated soot was 1-nitropyrene (1-NPYR), which increased linearly with reaction time for all NO2 concentrations chosen (0.11, 1.0, 2.0, 4.0 ppm, m m?1). Resulting 1-NPYR formation rate increased exponentially with [NO2]. Throughout the 3-h experiments less than 10% of pyrene has been converted to 1-NPYR and the partial reaction order with regard to [NO2] was estimated to 1.52. Benzo(a)pyrene (BaP) was more reactive than pyrene. After 3 h reaction time almost 80% of the BaP has been converted to 6-NBaP.Highest 1-NPYR concentrations on particles were detected at 373 K, and at higher temperatures a considerable decrease in particulate 1-NPYR was observed. A similar trend was observed in a DPF simulation system (PM-Kat®-like) with BaP-coated soot. In this case, highest 6-NBaP concentration on particles was detected at 423 K. Backed by corroborating results from separate gas/solid-phase partition experiments with 1-NPYR and 6-NBaP, it is likely that the newly formed 1-NPYR and 6-NBaP became transferred from particle to gas phase at higher temperatures. Results from this study confirm the presence of 1-NPYR and 6-NBaP in particulate and gas phase under conditions encountered in DPFs, especially when operated at low temperature situations of the aftertreatment system.  相似文献   
10.
Biomonitoring programmes provide relevant information, which may supplement ambient air pollution monitoring or modelling around emission sources. As a prerequisite, assessment scales for biomonitoring data have to be derived based on an objective evaluation of available data, as well as on a scheme of presentation, which is suggestive and easily understandable even for laymen. Based on an evaluation of numerous monitoring programmes, assessment scales for biomonitoring results are derived for plant biomonitoring, which also serve as a basis for the graphical presentation of monitoring results. This study is focussed on bioindicator plants like mosses (passive biomonitoring) and exposed lichens (active biomonitoring), in which 14 metal elements are investigated. As an example, data from a local biomonitoring network around a cement plant were used to demonstrate the use of the assessment scales derived and the presentation scheme developed. Data sets from about 15 moss and 24 lichen biomonitoring programmes, comprising more than 1000 specimens, were sorted by their pollutant characteristics in order to form the database. Data on the metal contents of species demonstrating similar values with respect to growth characteristics and habit, and representing background or low pollution levels, are aggregated and their statistical distributions are evaluated. Spacing of the assessment scales and their colour designations are derived from the 50-, 75-, 90- and 95-percentile values. Graphical presentation allows a comparison of the absolute values of metal contents and a relative association of measured values. Exemplary results from moss and lichen monitoring around a cement plant are generally below or slightly above the median values at background and low-pollution sites. Metal contents are higher in lichens compared to mosses for 7 elements (Cd, Cu, Hg, Pb, Sb, Sn, Zn), and are lower in lichens only for thallium. The assessment scheme presented is mainly aimed at the practitioner in the field of biomonitoring in order to provide a reliable and sound scale of assessment by comparison on an absolute scale rather than presenting the basis of ecological risk assessment. Differences in metal content of co-located samples of various moss species and possible correction procedures are briefly discussed- as well as the consequences of pooling monitoring data across various moss species for the quality of assessment scales. Further evaluations shall focus on species-specific rather than on pooled databases and will investigate the consequences of the use of correction factors when extrapolating metal data from one monitoring species to another.  相似文献   
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