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991.
介绍了太湖流域生态补偿现状,对太湖流域生态补偿的理论及存在的问题进行分析和探讨,提出太湖流域生态补偿关键要建立生态补偿法规、实施垂直统一的环境监测体系及对水质自动监测设施监管,为我国环境资源区域补偿实施提供借鉴。  相似文献   
992.
河源城南污水处理厂尾水深度处理效果的研究   总被引:1,自引:1,他引:1  
河源市城南污水处理厂利用垂直流人工湿地对该厂A2-O工艺处理的尾水进行深度处理,研究了人工湿地对尾水中TN、NH4+-N、TP、COD、BOD5的去除效果。结果表明:人工湿地对污水处理厂尾水具有较好的深度处理效果,垂直流人工湿地处理系统对尾水中TN、NH4+-N、TP、COD和BOD5平均去除率分别达到97.4%、97.8%、95.06%、91.87%和95.87%以上,其出水水质基本达GB 18918—2002《城镇污水处理厂污染物排放标准》一级A标准,地表水Ⅲ类标准。  相似文献   
993.
淀粉接枝改性阳离子化絮凝剂对城市污水以及采用絮凝法处理的废水具有良好的处理效果,但是淀粉絮凝剂几乎不溶于水,因此提高淀粉絮凝剂的溶解性,对于提高淀粉絮凝剂的絮凝效果具有重要的意义。本文采用α-淀粉酶对玉米淀粉进行水解,接枝共聚合成淀粉絮凝剂,通过改性最终制备得到水解淀粉接枝改性阳离子化絮凝剂,并通过试验对其合成指标进行了考察以及与普通淀粉絮凝剂的溶解性进行了对比。结果表明:水解淀粉接枝改性阳离子化絮凝剂在具备良好的絮凝效果的同时,其溶解度有了明显的提高。  相似文献   
994.
本研究以麻疯树(Jatropha curcas L.)和油桐(Vernicia fordii H.)幼苗为材料,考察了麻疯树和油桐幼苗的生理指标和稳定碳同位素组成对渗透胁迫的响应情况。结果表明,麻疯树比油桐更具有抗渗透胁迫能力,主要体现在:随着渗透胁迫程度的加剧,麻疯树叶片相对含水量与叶绿素含量的下降幅度均小于油桐,脯氨酸含量和可溶性糖含量的增加幅度高于油桐,相对电导率的上升幅度小于油桐;随着渗透胁迫程度的加剧,两种植物幼苗叶片的δ13 C值也都显著升高,但是在同一渗透胁迫水平下,麻疯树幼苗叶片的δ13 C值较油桐高,表明其拥有较高的水分利用效率,能够在干旱胁迫下更好地生长,暗示着植物叶片的δ13 C值在一定情况下可以表征植物的抗旱性。  相似文献   
995.
为分析北方寒冷地区浑浊型富营养化湖泊湿地浮游植物功能群时空变化特征及其影响因子,分别于2014年春季(5月)、夏季(7月)和秋季(9月)对小兴凯湖12个采样点进行了浮游植物采样,系统分析了浮游植物功能群的组成特征. 结果表明:小兴凯湖浮游植物共划分为21个功能群,其中重要功能群为H1、MP、D、C、Y、X2、J和W1,春季以功能群X2和D占优势,分别占49.02%和24.32%;夏季以功能群X2、C和H1占优势,分别占28.86%、16.11%和14.16%;秋季以功能群X2和C占优势,分别占46.97%和27.66%. 浮游植物功能群随季节变化表现为X2+D→X2+C+H1→X2+C的特点,反映至水体环境,春季为低温、高营养、中度浑浊水体,夏季为高温、富营养、高度浑浊、低光照水体,秋季为低温、富营养、高度浑浊、低光照水体. Pearson线性相关性分析表明,重要功能群功能群H1同ρ(TP)极显著正相关;功能群D同透明度、ρ(BOD5)极显著正相关,同ρ(CODCr)显著正相关,同浊度和ρ(TIC)显著负相关;功能群X2同透明度极显著正相关,同ρ(TP)显著正相关,同浊度极显著负相关. RDA多元统计分析表明,ρ(TP)、浊度、透明度是小兴凯湖浮游植物功能群的主要影响因子,ρ(TC)、ρ(TOC)同大多数小兴凯湖浮游植物功能群正相关,但不是主要影响因子,ρ(TIC)与小兴凯湖浮游植物功能群无相关性. 小兴凯湖虽然整体营养盐水平很高,但较高的浊度抑制了浮游植物的生长.   相似文献   
996.
Recent events have shown that humans may become infected with some pathogenic avian influenza A viruses (AIV). Since soil and water, including lakes, rivers, and seashores, may be contaminated by AIV excreted by birds, effective methods are needed for monitoring water for emerging viruses. Combining water filtration with molecular methods such as PCR is a fast and effective way for detecting viruses. The objective of this study was to apply a convenient method for the detection of AIV in natural water samples. Distilled water and lake, river, and seawater were artificially contaminated with AIV (H5N3) and passed through a filter system. AIV was detected from filter membrane by real-time RT-PCR. The performance of Zetapor, SMWP, and Sartobind D5F membranes in recovering influenza viruses was first evaluated using contaminated distilled water. SWMP, which gave the highest virus recoveries, was then compared with a pre-filter combined GF/F filter membrane in a trial using natural water samples. In this study, the cellulose membrane SMWP was found to be practical for recovery of AIVs in water. Viral yields varied between 62.1 and 65.9% in distilled water and between 1 and 16.7% in natural water samples. The borosilicate glass membrane GF/F combined with pre-filter was also feasible in filtering natural water samples with viral yields from 1.98 to 7.33%. The methods described can be used for monitoring fresh and seawater samples for the presence of AIV and to determine the source of AIV transmission in an outbreak situation.  相似文献   
997.
It has been recognized that the involvement of local community is essential to ensure the sustainability of A/R CDM (afforestation/reforestation clean development mechanism) project. This study verifies if the risks of non-permanence and leakage are addressed in a registered small scale A/R CDM project in Vietnam. Workshops, interviews, and a questionnaire survey of local villagers revealed that the project has caused a shortage of land for conventional activities such as grazing, fuel wood collection and shifting cultivation, and consequently posed the risks of project non-permanence and leakage. It is suggested that participation of all stakeholders in the community to the A/R CDM project beyond existing land tenure and adequate carbon benefit sharing according to the level of contribution to the project are required to reduce the risk of non permanence. To ensure the participation, the community should have capability such as consensus building and collective action. Leakage would be minimized if the community has alternative measures to the conventional activities before starting the project. We argue that it is necessary to first develop a community’s capabilities in the readiness phase of any A/R CDM project in order to reduce the risks for the project sustainability, and that new sources of funding are needed for this purpose.  相似文献   
998.
Indentifying common priorities in shared natural resource systems constitutes an important platform for implementing adaptation and a major step in sharing a common responsibility in addressing climate change. Predominated by discourses on REDD + (Reduced Emissions from Deforestation and Forest Degradation and conservation, sustainable management of forests and enhancement of forest carbon stocks in developing countries) with little emphasis on adaptation there is a risk of lack of policy measures in addressing climate change in the Congo Basin. Forest products and ecosystem services provide security portfolios for the predominantly rural communities, and play major roles in national development programmes in both revenue and employment opportunities. Thus, raising the profile of forests in the policy arena especially in the twin roles of addressing climate change in mitigation and adaptation and achieving resilient development is crucial. Within the framework of the Congo Basin Forests and Climate Change Adaptation project (COFCCA) project, science policy dialogue was conducted to identify and prioritize forest based sectors vulnerable to climate change but important to household livelihoods and national development. The goal of the prioritization process was for the development of intervention in forest as measures for climate change adaptation in Central Africa. Participants constituted a wide range of stakeholders (government, Non Governmental Organizations, research institutions, universities, community leaders, private sectors etc.) as representatives from three countries directly involved in the project: Cameroon, Central African Republic and Democratic Republic of Congo. Building on national priorities, four forest related sectors were identified as common priorities at the regional level for focus on climate change adaptation. These sectors included: (1) energy with emphasis on fuel wood and Charcoal; (2) Water principally quality, quantity, accessibility, etc.; (3) Food with emphasis on Non Timber Forest Products, and (4) Health linked to healthcare products (medicinal plants). Using these prioritized sectors, the project focused on addressing the impacts of climate change on local communities and the development of adaptation strategies in the three pilot countries of the Congo Basin region. The four sectors constitute the key for development in the region and equally considered as priority sectors in the poverty reduction papers. Focused research on these sectors can help to inject the role of forests in national and local development and their potentials contributions to climate change adaptation in national and public discourses. Mainstreaming forest for climate change adaptation into national development planning is the key to improve policy coherence and effectiveness in forest management in the region.  相似文献   
999.
Dissolved organic sulfur (DOS) is an important fraction for sulfur mobilization in ecosystem. In this work stream waters were sampled in 25 forested sites in southern China to study the dissolved sulfur fractions. Dissolved sulfur was fractionated into dissolved organic sulfur (DOS) and inorganic sulfate (SO42-) for 95 stream water samples. The results showed that the concentration of DOS ranged from 0 to 13.1 mg/L (average 1.3 mg/L) in all the streams. High concentrations of DOS in stream waters were found in the sites with high concentrations of sulfate. DOS constituted less than 60.1% of dissolved sulfur (average 17.9%). Statistical analysis showed that DOS concentration was correlated with SO42- in streams waters and total sulfur in surface layer soils. The results also showed that DOS concentration in stream waters had a seasonal variation, but no trends were found with it. The implication was that the long term sulfur deposition had led the increase of the concentration and fraction of DOS in stream waters in acid rain prevailing regions  相似文献   
1000.
李刚  李伟光  王广智  李鑫  公绪金 《环境工程》2012,(Z2):489-493,568
以城市生活污水厂脱水车间污泥为原料,采用化学活化法(ZnCl2为活化剂)在活化剂浓度为45%、活化温度为600℃、浸渍温度为45℃、活化时间为50min条件下制备污泥基活性炭。对污泥基活性炭进行了孔结构、扫描电镜(SEM)、红外光谱(FTIR)、XRD等表征分析。结果表明:该条件下制备出的污泥基活性炭碘吸附值为427.51mg/g,比表面积为329.48m2/g,大孔、中孔、微孔容积分别为0.19,0.12,0.15cm3/g。平均孔径为3.953nm。将其应用于生活污水处理,考察了污泥基活性炭投加量、pH、吸附时间对其吸附性能的影响。  相似文献   
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