垂直流人工花卉湿地模拟系统净化污水的效果

通过在垂直流模拟人工土柱上种植不同的花卉植物，研究了垂直流花卉人工湿地对污水COD、BOD5、TN和TP的净化效果的影响。结果表明，所选用的5种陆生花卉，甚至鲜切花卉对化粪池污水有比较好的净化效果，它们对BOD5的去除率可达到92．04％以上，对TP的去除率甚至可达到97．77％以上。而且种植花卉植物的人工湿地出水水质要好于不种植物的对照湿地系统。     

活性污泥-人工湿地组合处理系统中污染物的去除

通过12个月的现场监测试验,研究了活性污泥法与四个串联潜流人工湿地构成的组合处理系统对农村生活污水的处理效果及其影响因素.结果表明,当平均处理量为82 T·d-1(36-132 T·d-1),湿地系统水力负荷为0.52-1.88 m·d-1时,组合处理系统对TSS,AN,TP,COD和BOD5的去除率分别为75%,71%,38%,81%和88%;湿地系统对COD,BOD5,SS,AN和TP的去除率分别为39%,55%,48%,5%和18%.方差分析表明,影响组合系统处理效果的主要因素是水力负荷及处理单元;湿地系统中有机污染物(COD,BOD5,SS)的去除主要是由第一块湿地完成的,而AN及TP的去除却呈现"累积"的特点;结合电子受体SO42-,NO3-及NO2-在湿地系统中的浓度变化趋势,推测湿地系统中有机污染物的生物去除主要是通过反硝化脱氮进行的,而通过硫酸盐还原(在硫酸盐还原菌的作用下)却是次要过程.     

Amphibian Breeding Distribution in an Urbanized Landscape

Abstract:  Amphibians commonly use wetlands for breeding habitat, and given the concern about their ongoing global declines, the effects of urbanization on the breeding distribution of amphibians need to be quantified. Thus, we conducted a survey of the larval amphibian community in central Pennsylvania (U.S.A.) wetlands along an urbanization gradient. Wetlands in urban areas had less surrounding forest and wetlands and greater road density than rural wetlands. Urbanization was also associated with increases in hydroperiod (i.e., wetland permanency) and the presence of fish predators. Moreover, urban wetlands had lower larval amphibian species richness than rural wetlands. This decrease in richness was attributable to a decrease in occurrence of wood frogs ( Rana sylvatica ) and ambystomatid salamanders ( Ambystoma maculatum and A. jeffersonianum ) in urban sites. Wood frogs and ambystomatid salamanders were positively associated with the amount of forest surrounding sites and negatively associated with hydroperiod. As a result, we hypothesize that these species are sensitive to the effects of urban development. The remaining species in this study appear fairly resilient to the effects of urbanization. These data demonstrate the importance of quantifying both local and landscape attributes when describing the factors that limit the breeding distribution of amphibians. We recommend that to preserve amphibian biodiversity in urbanized landscapes, it is best to focus on regional diversity, which protects a variety of sites that encompass various hydroperiods, have adequate buffer habitat, and are connected by dispersal routes.     

表面流人工湿地处理生活污水的研究

通过小试装置研究了表面流人工湿地对人工模拟生活污水的处理效果及相关运行参数。实验结果表明，表面流人工湿地系统对污水中的CODcr、TN、TP均有较好的综合净化能力，对各种污染物指标的去除率可分别达到CODcr 75％、TN75％、TP73％，其中CODcr和TN达到一级排放标准分别需3d和4d的表观停留时间，TP要达到二级排放标准则需6d的表观停留时间。而且，湿地植物对TN和TP的去除有比较明显的促进作用。     

人工湿地植物处理污水的试验研究

为了选择适合在中国四川地区生长的湿地植物，作者在四川省成都市１９９３年１０月２日－１１月１９日的深秋季节进行了湿地系统处理模拟污水的盆栽静态试验，以研究多种湿地植物在自然环境条件下对污染物的去除情况。试验发现，灯蕊草，芦苇，菖蒲这三种植物在１４天内均能去除模拟水样中的ＣＯＤｃｒ，其中，芦苇的去除率为３８％，菖蒲的去除率为４１％，灯蕊草的去除率为４２～４６％。这三种植物同时也能污水的ｐＨ从３．５调节     

Large-scale shrimp farming in coastal wetlands of Venezuela,South America: Causes and consequences of land-use conflicts

In Venezuela, large-scale shrimp farming began in the 1980s. By 1987, the Ministry of Environment and Natural Resources (MARNR) had received 14 proposals for approval. A developer illegally started the construction of ponds at the Píritu Lagoon in the State of Anzoátegui before the authorization process was completed. This action triggered a land-use conflict. This study identifies the causes for public protest and determines the consequences of this conflict for land-use management. The results show that public protest was based on the impacts of the partial construction of ponds. These impacts were related to direct removal of wetlands, interruption of natural patterns of surface flows, and alteration of feeding grounds of some bird species with migratory status. Consequences were identified in relation to the role that nongovernmental organizations (NGOs) play in land-use conflicts and the actions that MARNR could take in the future to prevent and solve similar situations.     

聚丙烯小球对人工垂直潜流湿地氮磷去除性能的优化研究

采用页岩和香蒲(Typha latifolia L.)构建人工垂直潜流湿地处理津河富营养化水体,并用聚丙烯小球替代部分页岩研究其对垂直潜流湿地氮磷去除性能的影响.设计水力负荷800 mm/d,理论水力停留时间12h.试验期间(2006-06～2006-11),氮磷月平均去除率在8月份达到最大值.与全页岩湿地相比,聚丙烯小球使氨氮(NH 4-N)、总氮(TN)、溶解性活性磷(SRP)和总磷(TP)月平均去除率分别提高13.38%、8.9%、9.29%和8.25%,使用聚丙烯小球能够有效提高人工垂直潜流湿地氮磷去除效率.试验结束后收割香蒲地上组织(茎和叶),测定地上组织生物量及茎、叶中的氮磷含量.结果表明,聚丙烯小球虽然抑制香蒲地上组织生物量的增加,但却能够有效提高茎、叶中氮磷含量.通过收割香蒲地上组织可使TN和TP去除分别增加29.382 g·m-2和13.469 g·m-2.     

人工湿地中微生物生态的研究进展

人工湿地作为一种廉价的传统废水处理技术的替代技术已被应用于多种废水的处理。目前对湿地系统中水生植物、微生物、基质和污染物之间的相互作用机理还不完全清楚,文章从微生物生态的角度论述了微生物在人工湿地中的分布特征及影响因素,水生植物对微生物的作用,以及目前微生物多样性研究的策略。     

低温条件下湿地氨氮强化净化技术及其氨氧化微生物机制

针对北方寒冷冬季水源地氨氮微污染水体的特征,构建间歇流人工湿地系统并同步采用分子生物学方法对湿地系统中的氨氧化古菌和氨氧化细菌的丰度和古菌的多样性进行分析,并结合硝化速率潜势来研究氨氧化古菌和氨氧化细菌在氨氧化过程中的作用.结果表明:平均气温为5℃时,最佳运行工况为:停留时间21 h,水力负荷4.2 cm·d-1,氨氮去除率达99%;平均气温为-5℃时,最佳运行工况为:水力停留时间为21 h,水力负荷3.6 cm·d-1,氨氮去除率达81%,去除效率稳定.在低温条件下,氨氧化古菌和氨氧化细菌中amoA基因的丰度会因温度降低而减少,古菌中amoA基因丰度高于细菌2.9~33.2倍,且硝化速率潜势与氨氧化古菌中amoA基因丰度呈正向变化趋势,而与氨氧化细菌无显著相关,表明氨氧化古菌在低温条件下的氨氧化过程中起主导作用.湿地系统中的氨氧化古菌的生物多样性具有季节性变化,系统发育分析显示,夏季样品8个OTU全部属于土壤支系;冬季样品11个OTU序列属于土壤支系,2个OTU序列属于海洋水体支系,多样性较高.夏季和冬季样品中氨氧化古菌均属于一个新命名的古菌类群——奇古菌门(Thaumarchaeota).本文建立了一种在低温条件下基于氨氧化古菌有效强化湿地氨氮净化处理的稳定运行技术,为寒冷地区强化湿地去除氨氮提供了理论依据.     

几种人工湿地基质对磷素的吸附作用研究

从吸附动力学角度出发,研究了干渣、沸石、页岩陶粒和白云石四种基质对水体中磷素的吸附作用,结果表明,干渣对磷素的吸附量最大,其次是沸石和页岩陶粒,白云石对磷素的吸附量最小。作用48h后,干渣对磷素的吸附量分别是沸石、页岩陶粒和白云石的3.9倍、6.7倍和11倍。一级动力学方程、Elovich方程和双常数速率方程均能很好地描述人工湿地基质对磷素的等温吸附动力学特征,但从相关系数来看,Elovich方程的描述更为准确。四种基质对磷素的吸附速率依次为:干渣>页岩陶粒>沸石>白云石。