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131.
本文分析了公众参与瑞典自然资源管理的4个主要模式,也根据瑞典西海岸两个城市有关沿海资源冲突的经验研究评价了其中一个模式(参与自然环境/空间规划)的优势和不足.与其他行政和规划程序相比,自然规划为协调部门和资源之间土地和水域的管理,也为扩大利益相关者的参与提供了可能性.海岸带管理的地区性影响随着最低的法定条件之外的参与而增加,尽管参与的管理框架和实践需要进一步发展.除了培训专业人员和对现有的程序组合进行实验外,从长远看,使法规适应海岸带综合的和可持续的管理要求是必要的.  相似文献   
132.
We examined the effect of increased copper concentrations (0–10 μM) on hydrothermal vent micro- organisms and the production of copper (Cu)-binding ligands as a response. Hydrothermal vent microbes originated from diffuse fluids at the Lilliput mussel field and the Irina II site in the Logatchev hydrothermal vent field, both on the Mid-Atlantic Ridge. Parallel studies were also conducted with amino acids supplemented to the incubations in order to verify whether dissolved amino acids, present in hydrothermal fluids, can buffer the bioavailable copper and reduce the active production of Cu-binding ligands. In all incubations, ligand concentrations increased with rising copper concentrations, but microbial cell numbers remained constant. This study shows that microbes were able to cope with as much as 10 μM dissolved copper by buffering the free copper concentration. The presence of amino acids had no significant influence on the active ligand production. Our results imply that mediation of chemical speciation by vent microbes may have an important impact on hydrothermal trace metal fluxes into the ocean.  相似文献   
133.
The behavior and fate of triasulfuron (TRS) in water and soil systems were examined in laboratory studies. The degradation of TRS in both buffer solution and soil was highly pH-sensitive. The rate of degradation could be described with a pseudo first-order kinetic and was much faster at pH 4 than at pH 7 and 9. Aqueous hydrolysis occurred by cleavage of the sulfonylurea bridge to form 2-(2-chloroethoxy) benzenesulfonamide (CBSA) and [(4-methoxy-6-methyl-1,3,5-triazin-2-yl)amino] (AMMT). AMMT was unstable in aqueous solutions in any pH condition but it degraded more quickly at pH 4 and 9. CBSA did not degrade in aqueous solutions or in enriched cultures but it underwent a quick degradation in the soil. The rates of TRS degradation in sterile and non-sterile soils were similar, suggesting that microorganisms played a minimal role in the breakdown process. This hypothesis is supported by the results of studies on the degradation of TRS by enriched cultures during which the molecule underwent a prevalently chemical degradation.  相似文献   
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Current knowledge on the abundance and distribution patterns of different soft coral species is relatively limited when compared to other benthic suspension feeders such as gorgonians and hard coral species. To overcome this scarcity of information, the distribution patterns of the soft corals Alcyonium acaule and Alcyonium palmatum were investigated in northwestern Mediterranean benthic communities over a wide geographical (60 km of coastline) and bathymetrical (0–70 m depth) extent using a remotely operated vehicle. A. acaule was the most abundant species in the study area with highest recorded density of 18 col m?2 found at depths of 35–45 m in areas that are directly exposed to strong near-bottom currents. Conversely, A. palmatum was only found as scattered solitary colonies at greater depths in soft bottoms, with maximum density of 2.4 col m?2. Medium and large colonies of A. acaule were preferentially found on sloping and vertical rocky bottoms where they form dense patches. High-density patches of A. acaule were preferentially found on vertical rocky bottom, while isolated colonies were preferentially observed on coralligenous substrata as well as on flat soft and maërl substrates. A. acaule biomass distribution showed highest values between 40 and 45 m depth, and between 60 and 65 m depth. This suggests that deeper populations are formed by colonies that are bigger than the equivalent shallower ones. Although both species are almost genetically identical, ecologically they are very different. For this reason, conservation plans should consider the differential ecological traits shown by these two soft coral species.  相似文献   
137.
The emerging challenge of managing increasing volumes of urban sewage has resulted in municipalities pursuing sustainable ways to manage urban biosolids and their by-products. Using content analysis of public debates, and situating the debate within science, policy and facility siting literature, this study examines claims and counterclaims relating to the siting of a biosolid processing facility in rural Ontario. The equivocal evidence on the health and environmental effects of biosolids resulted in a heated “expert versus lay” debate. The study critically evaluates the importance of trust and the shifting role of scientific evidence in politicised settings, while making relevant policy recommendations.  相似文献   
138.
One of the main limitations for a wider application of surfactants in soil remediation is the lack of knowledge about environmental fate and toxicity of surfactant itself especially for in situ application. Sorption behaviour, biodegradability, toxicity of parent compound and its metabolites are important processes that affect environmental fate of surfactants in site remediation applications. Tween 80 (poly(oxyethylene)(20)-sorbitane monooleate) and Aerosol MA+80 (dihexyl sodium sulfosuccinate) are surfactants that have been tested in laboratory and field scale remediation of soil and groundwater. In this work, the sorption and biodegradability of these surfactants were assessed to provide conditions and limitations for their use. The soil used in this experimentation was analysed for organic carbon content, soil bacteria, and size fraction and resulted to be a good model because is characterised by mean values for almost all considered parameters. Tween 80 showed high degree of biodegradability but a high affinity for soil matrix. Results suggest that Tween 80 could find its best application in ex situ solid phase remediation like ex situ bioremediation; its high affinity to soil could limit in situ applications. Biodegradation tests for Aerosol MA+80 show low degree of biodegradability and mineralisation. Biodegradation experiments, coupled with analysis of toxicity, could support the hypothesis that degradation of Aerosol MA+80 is not complete and leads to an accumulation of intermediates with at least the same toxicity of the parental compound. Therefore, aquifer remediation application with Aerosol MA+80 has to be conducted with necessary precautions to avoid product loss and excess surfactant should be flushed from the soil.  相似文献   
139.
Artemisia lerchiana is a wormwood species of the Central Asian steppe regions, where it completely cover whole areas. For the first time it was possible to show through field experiments that C(1)/C(2) halocarbons (VCHCs), such as chloroform (CHL), tetrachloroethene (PER) and hexachloroethane (HEX), can be taken up by test plants of the species A. lerchiana via the soil/root pathway and metabolised inter alia into trichloroacetic acid (TCA) under semi-aride conditions. At the same time, chlorophyll a fluorescence measurements carried out on the test plants revealed a phytotoxic influence on plant vitality (max. decline in vitality of 52% with application of CHL) and less efficient energy flows in the photosynthesis mechanism of the A. lerchiana test plants. The authors examine possible links between the simultaneous appearance of VCHCs and additional drought stress in the acceleration of desertification processes.  相似文献   
140.
The concentration of the estrogens 17β-estradiol, estriol, estrone, 17α-ethinylestradiol, mestranol and norethisterone and of the anthropogenic gadolinium (Gdant) has been determined in the creeks and rivers, sewage treatment plants and water works of the city of Prague. The rapid degradation of estrogens in surface water allows the estrogen concentration gradient to be used as a very precise and sensitive guideline by which to pin-point sewage leaks into surface run-off water. The rather conservative behavior of Gdant in surface and ground water documents in the present case the presence of sewage water in the surface water cycle.  相似文献   
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