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41.
Globally, marine protected areas (MPAs) have been relatively unsuccessful in meeting biodiversity objectives. To be effective, they require some alteration of people's use and access to marine resources, which they will resist if they do not perceive associated benefits. Stakeholders’ support is crucial to ecological success of MPAs, and their support is likely to depend on their capacity to adapt to and benefit from MPAs. We examined the influence of social adaptive capacity (SAC) on perceived benefits of MPAs in Siquijor, Philippines, in the Coral Triangle. This region has substantial biodiversity and a population of over 120 million people, many of them dependent on marine resources for food and income. The region has many MPAs, most of which are managed under decentralized governance systems. We collected survey data from 540 households in 19 villages with associated MPAs. We evaluated the influence of multiple SAC variables (e.g., occupational multiplicity and social capital) on perceived benefits with decision trees (CHAID) and qualitatively analyzed this relationship with respect to types and recipients of benefits. Our models revealed the key role of social capital, particularly trust in leadership, in influencing perceptions of benefits (χ2 = 14.762, p = 0.000). A path analysis revealed that perceptions of distributional equity were a key mechanism through which social capital affected perceived MPA benefits (root mean‐square error of approximation = 0.050). Building social capital and equity within communities could lead to more effective management of MPAs and thus to expenditure of fewer resources relative to, for example, regulation enforcement.  相似文献   
42.
One goal of the Swedish survey project is to discover possible sources of PCDD/F. Bottom sediment and pike were sampled at various sites near different types of industries along the coast line of two lakes and one river. The results show background levels of PCDD/F in some lakes which can only be explained by atmospheric input. In some lakes paper mill emissions of chlorinated PCDD/F give high levels of local contamination (≈1 ng/g IG) within short distances (<1 km) from the source. PCDD/F from paper mill effluents are transported long distances and traces can be detected over the entire lake area. The PCDD/F levels in pike are correlated with levels in the underlying sediment.  相似文献   
43.
中段废水是制浆造纸工业的主要污染源之一,从工程设计的角度出发,对草制浆造纸中段废水处理及回用提出一套可行适用的工艺方案;对主要工艺环节参数、设备备有说明,以供同行借鉴.  相似文献   
44.
The most abundant volatile organochlorine compounds (VOCCs), trichloroacetic and dichloroacetic acids and AOX, were determined in bleaching effluent and waste water from three kraft pulp mills during ClO2 bleaching. 0.6–7.7 g of VOCCs per ton bleached pulp were formed, the most abundant being chloroform and dichloroacetic acid methyl ester. Most of the VOCCs were removed during treatment, and it was estimated that 2–30 t of VOCCs would be removed annually from activated sludge treatment plants in Finnish kraft pulp mills using elemental chlorine free bleaching, most likely by volatilization. Dichloroacetic acid was formed in considerably higher amounts than trichloroacetic acid, and both compounds were removed effectively during treatment. The formation of all organochlorine compounds decreased considerably when non-chlorinated bleaching was employed.  相似文献   
45.
光释光信号已被成功地应用于岩石表层暴露、埋藏年龄的测定以及判别岩石经历的曝光和埋藏历史。本文选择红褐色石英砂岩和灰白色黑云母花岗岩进行了岩块和岩片晒退不同时间的实验研究,结果显示:岩石光释光信号(IR_(50);IRSL)可被光(阳光和全光谱模拟太阳灯灯光)快速晒退。曝光一定时间后,岩块表层一定深度的光释光信号可以归零,且随曝光时间的延长,自暴露面向内的光释光信号归零深度也随之加深。砂岩和花岗岩光晒退对比实验结果显示:与深色砂岩相比,浅色的花岗岩有更高的光释光信号晒退速率。实验同时揭示:本研究所采用的红外光源激发获得的光释光信号来自岩片(1.2 mm)表层一定深度,并没有完全穿透该岩片。该研究为了解不同岩性岩石的光释光信号晒退速率、测年对象的合理选择以及岩石样品采集、前处理和测试等提供了实验数据支持。  相似文献   
46.
In zooxanthellate corals, the photosynthetic fixation of carbon dioxide and the precipitation of CaCO3 are intimately linked both spatially and temporally making it difficult to study carbon transport mechanisms involved in each pathway. When studying Tubastrea aurea, a coral devoid of zooxanthellae, we can focus on carbon transport mechanisms involved only in the calcification process. We performed this study to characterize T. aurea carbonic anhydrase and to determine its role in the calcification process. We have shown that inhibition of tissular carbonic anhydrase activity affects the calcification rate. We have measured the activity of this enzyme both in the tissues and in the organix matrix extracted from the skeleton. Our results indicate that organic matrix proteins, which are synthesized by the calcifying tissues, are not only structural proteins, but they also play a crucial catalytic role by eliminating the kinetic barrier to interconversion of inorganic carbon at the calcification site. By immunochemistry we have demonstrated the presence of a protein both in the tissues and in the organic matrix, which shares common features with prokaryotic carbonic anhydrases.  相似文献   
47.
Coral reefs are highly dynamic and productive marine ecosystems, providing habitat and refuge for an enormous number of species including fish, invertebrates and algae. With increased anthropogenic pressures and global climate change, many coral reefs are rapidly declining. Currently, there is limited knowledge on condition and community assemblage composition of shallow fringing coral reefs along the south-eastern coast of Queensland, Australia. With increased demand to determine existence of coastal fringing reefs by National Regional Management groups, a rapid cost effective method to determine reef composition and condition was required. The aim of this study was to determine the benthic structure and extent of two small coastal fringing reefs (Hummock Hill Reef and Stringers Reef) along the Southern Great Barrier Reef. Reef substrate assessments were carried out using a rapid assessment technique and a Point Intercept Method (PIM). The data were analysed and classified using a Geographic Information System (GIS). Percent substrate cover was calculated using a visual basic image analysis program. The Point intercept method showed higher accuracy over the rapid assessment technique (up to 15–40% difference) and was thus deemed a more suitable classification tool for reefs with high structural complexity and heterogeneity. This study focused on piloting a rapid, cost effective Point Intercept Technique using random point count methodology to document coral benthic habitat and extent over a commonly used rapid assessment method as a tool for reef coastal management and conservation. The two techniques were compared and substrate classification success, limitations and errors were discussed.  相似文献   
48.
用含氯漂白废水驯化城市污水处理厂的好氧污泥 ,从中分离出两株高效去除有机氯的菌 ,并对其适应条件进行了研究。结果表明 ,当pH为 7.0、废水浓度为 5 0 %、加入 0 .4g/L葡萄糖、2mL菌液时 ,处理效果较好 ,有机氯的去除率最高可达 74 .8%。  相似文献   
49.
Torrades F  Pérez M  Mansilla HD  Peral J 《Chemosphere》2003,53(10):1211-1220
Multivariate experimental design was applied to the treatment of a cellulose conventional bleaching effluent in order to evaluate the use of the Fenton reagent under solar light irradiation. The effluent was characterised by the general parameters total organic carbon (TOC), chemical oxygen demand and color, and it was analysed for chlorinated low molecular weight compounds using GC–MS. The main parameters that govern the complex reactive system: Fe(II) and H2O2 initial concentration, and temperature were simultaneously studied. Factorial experimental design allowed to assign the weight of each variable in the TOC removal after 15 min of reaction. Temperature had an important effect in the organic matter degradation, especially when the ratio of Fenton reagents was not properly chosen. Fenton reagent under solar irradiation proved to be highly effective for these types of wastewaters. A 90% TOC reduction was achieved in only 15 min of treatment. In addition, the GC–MS analysis showed the elimination of the chlorinated organic compounds initially detected in the studied bleaching effluents.  相似文献   
50.
We present evidence from studies oflakes in Killarney Park, Ontario, Canada that waterclarity is a key variable for monitoring theeffects of climate change, high UV exposure andacidification. In small oligotrophic lakes, thesestressors affect water clarity primarily byaltering the concentration of DOC in lake water. Clear lakes (<2 mg L-1 DOC) proved to be highlysensitive indicators of stressors, exhibiting largethermal and optical responses to small changes inDOC. Extremely clear (<0.5 mg L-1 DOC) acidic lakesshowed the effects of climate change and solarbleaching in recent decades. These lakes becamemuch clearer even though they were slowlyrecovering from acidification.  相似文献   
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