铁岭市莲花湖湿地生态系统对城区污水中氮、磷的去除效果分析

铁岭市位于辽宁省北部,主城区人口约40万人,城区污水排放量约14万m2／d,由城市排水管网收集后入污水处理厂集中处理。城区污水处理厂出水首先排入莲花湖湿地,经湿地生态系统净化后入凡河Ⅳ类水域,最终入辽河V类水域。利用人工湿地净化铁岭城市污水,对治理辽河水流域污染具有重要意义。本文根据城市污水在莲花湖人工湿地的走向以及莲花湖人工湿地的单元构成,对湿地主要构建单元的水质进行监测,分析莲花湖人工湿地净化城市污水中氮、磷污染物的净化效果,探求城市生态环境可持续发展的新思路。     

盐度和水淹对短叶茳芏枯落物分解和二氧化碳释放的影响

在全球气候变暖和盐水入侵的背景下,探究湿地枯落物分解和CO_2释放对盐度和水淹的响应具有重要意义.以闽江河口湿地的短叶茳芏为研究对象,模拟不同盐度和水淹条件下枯落物分解.研究结果表明:(1)盐度升高抑制枯落物的分解(p0.01),低盐(5)、中盐(10)、高盐(15)在非水淹条件下分别比对照(0)的失重率平均减少10.83%、17.93%和29.39%,水淹条件下平均减少24.18%、31.62%和47.46%.(2)对照组的枯落物分解速率为水淹条件(0.0070 d~(-1),t_(0.95)=0.76 a)大于非水淹条件(0.0051 d~(-1),t0.95=0.94 a),而处理组的枯落物分解速率和CO_2释放速率均呈现出非水淹条件大于水淹条件.非水淹的枯落物CO_2释放通量比水淹条件的增长7.05%~86.23%.(3)在枯落物分解95%的干物质的期间内,与水淹条件相比,非水淹对照组平均每g干物质释放的CO_2高于水淹对照组34.49%;然而,随盐度升高,非水淹条件下的平均每g干物质释放的CO_2受抑制.(4)盐度和水淹对枯落物残留量的贡献率分别为24.82%和14.29%,对枯落物CO_2释放通量的贡献率分别为75.62%和6.13%.     

长江口滩涂湿地重金属的分布格局和研究现状

综述长江口滩涂湿地重金属在各储存库的分布格局,分析重金属含量的变化及其产生原因,评价长江口滩涂湿地目前的环境状况,试图对湿地重金属研究提出科学的建议。     

三江平原气候变暖的进一步认识:最高和最低气温的变化

利用三江平原17个站1951-2000年的平均最高、最低气温和气温日较差资料，采用线性倾向估计和几种突变检测方法，定量研究了最高、最低气温和气温日较差变化趋势的空间分布，比较了最高、最低气温变化特征的差异性。结合前期的相关研究结果，对研究区20世纪70年代中期以来的三江平原气候变暖过程和成因有了进一步的认识。1975—2000年的变暖时期主要由两个阶段构成：1975—1987年为第一阶段，以夜间升温为主要特征，相对应的是气温日较差明显减小，超过一定面积的湿地开垦是该阶段气候变暖的主要驱动力之一；1987-2000年为第二阶段，以白天和夜间同时升温且幅度相当，气温日较差没有明显的变化趋势为特点，这一阶段的升温是对全球气候变暖同步的区域响应。     

湿地构成变化与湿地保护

湿地不合理的开发利用 ,对湿地构成诸如水文、土壤、水质、植被和动物都造成了不同程度的负面影响 ,这些影响相互作用 ,使得湿地生态系统极为脆弱 ;通过对它们的分析 ,提出了相应的湿地保护措施     

3种不同基质潜流湿地对磷的去除效果

基质是潜流式人工湿地污水处理系统的重要组成部分,直接影响到系统的处理效果.本文研究了由沸石、页岩陶粒和碎石3种不同基质构建的潜流式人工湿地对磷的去除效果.结果表明,在设计水力停留时间3 d,连续进出水情况下,碎石单元对磷的去除效果最好,页岩陶粒单元次之,沸石单元效果最差,平均去除率分别为95%、60%和35%.在潜流式人工湿地污水处理系统运行初期观察到磷释放现象,沸石单元最为明显.进水磷浓度较低时,磷的去除率随浓度升高而升高,当正磷、总磷浓度分别升高到2.4～2.5和3.1～3.3 mg/L时,正磷、总磷的去除率开始迅速下降.     

淮安湿地现状调查和可持续发展

从2004-2006年上半年以来，对淮安市的湿地现状进行了调查，并对其功能、效益进行了分析，指出了淮安市湿地保护存在的问题，同时强调必须要运用宣传教育、科学规划、统筹兼顾、协调管理、加大投入等手段来保护生物多样性，实现环境、经济、社会效益的可持续发展。     

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。     

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.