中国图们江流域湿地现状及其存在问题

对图们江流域的湿地现状及类型进行了详尽的论述，对图们江流域湿地存在的问题和围垦造田、经济发展、水质污染等因素对湿地的影响进行了阐述。     

曲阜市湿地生态保护初探

通过对曲阜市地理位置和自然资源现状、湿地类型和面积、湿地植被、湿地动物、湿地水生生物等基本情况的详细调查，客观地做出了曲阜市的湿地生态环境评价，提出了做好宣传唤起公众参与保护的意识，兼顾保护和利用并重，加大科技支持力度等湿地保护建议，以保持湿地生态平衡，促进社会经济与生态环境的协调发展。     

拉萨河流域高寒湿地水质影响因子分析

西藏高寒湿地在生态平衡、生态建设和经济社会发展中发挥着重要作用。本文以西藏拉萨河流域内各个典型高寒湿地为研究对象,通过系统聚类法和综合污染指数法,对流域内各项水质指标进行综合分析和评价。结果表明：各个湿地的总N、Cu元素含量都超出了Ⅰ类水质标准;总P、Zn没有超标;Mn元素含量除了塘嘎郭湿地超标3倍外,其他均小于国家标准;Fe元素含量除了塘嘎郭湿地超标7倍外,其他均小于标准。总N、总P、pH值、Cu、Fe等因子对拉萨河流域内各个高寒湿地水质污染贡献最大。拉萨河水体有机污染较重,其余各个湿地有水体富营养化的趋势,同时流域内湿地独特的自然因素造成该流域内重金属污染偏高。对策建议包括应加大对城市污水的治理,加强流域内及周边矿藏资源的开发管理等。     

人工湿地控制非点源污染的应用

随着点源污染的有效管理和控制，非点源污染已成为水环境污染的主要原因。人工湿地作为一种控制水环境非点源污染的有效工具，已被世界上很多国家所认可。本文首先简述了非点源污染的危害，其次对人工湿地的概念和类型进行了介绍，论述了人工湿地对非点源污染中氮、磷、重金属和农药等主要污染物的去除机理，最后对人工湿地处理系统的附属设施、水力因素、表土层以及植物收割等应用问题进行了探讨。     

黄河三角洲湿地生态环境现状的调查研究

通过对黄河三角洲湿地类型及分布的调查以及对三角洲环境空气质量、地表水环境质量、湖泊水库水环境质量、浅海湿地水环境质量和湿地生态系统现状进行了调研,结果表明,三角洲湿地环境均受到不同程度的污染,浅海湿地潜在富营养化的危险,湿地生态系统现状堪忧.     

基于RS与GIS的莱州湾南岸滨海湿地景观类型与破碎化分析

应用Landsat--7遥感数据和GIS技术对莱州湾南岸滨海湿地类型、面积和分布现状进行了调查,并对滨海湿地景观特征及景观破碎化程度进行了分析.结果表明,研究区景观类型以盐田、滩涂和养殖池为主,人工湿地面积占整个湿地面积的78.22%.该区主要受人为干扰活动影响,区域景观斑块破碎化程度较高,对研究区湿地产生了严重的影响,因此合理调控人类干扰活动是改善莱州湾南岸滨海湿地环境的根本途径.     

青海省湿地类型保护区现状与发展对策

文章从青海高原湿地资源现状和湿地类型自然保护区发展的角度，分析目前高原湿地保护中存在的问题，提出了今后青海湿地类型保护区发展对策。     

西藏掠影

<正>西藏遵循‘‘保护中开发,开发中保护"的原则,大部分区域仍保持着原生态,西藏仍然是世界上环境质量最好的地区之一。但是,近年来,拉萨河谷高寒湿地—拉鲁湿地生态系统健康程度处于快速下降状态。人为侵占、乱占湿地,盲目开发、过度放牧的现象十分严重;加上人们毫无顾及地向湿地倾倒生活生产垃圾,排放未经任何处理的生活、生产污水,拉鲁湿地的生态环境系统遭了严重的破坏。图为拉萨河现状。     

潜流湿地处理旅游区生活污水生产试验:以COD为例

以某大型潜流人工湿地污水处理工程为实验基地，对潜流人工湿地工艺进行生产研究，本文介绍其对COD的去除性能。该工程COD进水平均98mg／L，出水平均38mg／L，达到GB18918-2002中一级A排放标准。当单级湿地进水COD浓度小于80mg／L，两级串联湿地进水COD浓度小于100mg／L时，可使湿地出水浓度小于50mg／L。工艺类型上，下行流湿地优点突出、最为全面，优势明显。不同植物配置上，本生产实验条件下，一级湿地种植芦苇和芦竹去处效果接近，二级湿地不同植物优劣排序：灯芯草〉美人蕉〉香蒲〉水竹〉香根草。     

东洞庭湖湿地生态旅游开发与持续利用研究

东洞庭湖湿地是我国长江中下游地区三大湿地资源集中地之一，在其特殊的地理环境、自然条件和人类活动的长期共同作用下，形成了独特的湿地生态旅游资源景观。文章分析了东洞庭湖湿地旅游资源的特征，提出了不同类型湿地生态旅游的开发模式，并在此基础上，提出了持续开发湿地旅游资源的对策建议，以期为全面开发湿地的社会、经济和生态综合效应，实现湿地生态旅游资源的持续利用，提供决策参考。     

Regional priorities for wetlands conservation in West Asia and North Africa

Though characterized by a scarcity of water, West Asia and North Africa region has a large number of wetlands of various types supporting a rich biodiversity. However, the government efforts to reverse the trend of wetlands degradation fall short of the policy goals due to various reasons. The paper outlines the priorities for wetlands conservation in the region.     

Wetland loss and substitution by the Section 404 permit program in southern California,USA

To test the effectiveness of the 404 permit program in preventing a net loss of wetland resources, 75 Section 404 projects permitted in the years 1987–1989 and located in a portion of southern California were evaluated. From this group of projects, 80.47 ha of wetlands were affected by Section 404 permits and the Army Corps of Engineers required 111.62 ha of wetland mitigation. To verify the successful completion of each mitigation project, all 75 project sites were visited and evaluated based on the amount of dead vegetation, growth and coverage, and the number of invasive species. Based on the field verification results, the actual amount of completed mitigation area was 77.33 ha, resulting in a net loss of 3.14 ha of wetland resources in the years 1987–1989. By comparing the types of wetlands lost to the types of wetlands mitigated, it is apparent that, in particular, freshwater wetlands are experiencing a disproportionately greater loss of area and that riparian woodland wetlands are most often used in mitigation efforts. The net result of these accumulated actions is an overall substitution of wetland types throughout the region. Results also indicate that, typically, large-scale mitigation projects are more successful compared to smaller projects and that successful compliance efforts are not evenly distributed throughout the region. We recommend that better monitoring, mitigation in-kind, mitigation banking, and planning on a regional or watershed scale could greatly improve the effectiveness of the Section 404 permitting program.     

生态文明视域下河北沿海地区湿地农业发展转型研究

基于生态文明建设视域,分析了河北沿海地区湿地农业发展现状,指出目前存在天然湿地面积逐年减少、抵御自然灾害能力降低、水资源及环境条件恶化、湿地功能发挥受到限制等主要问题,阐释了湿地农业发展转型的必要性,提出实现湿地农业持续发展,必须推动其增长方式向依靠科学技术和科学管理转型,生产方式向依靠基础设施和技术装备转型,经营方式向适度规模经营转型,农产品向多品种、高品质转型,发展方式向多次产业融合转型。     

Quantitative assessment of tidal wetlands using remote sensing

Effective management of tidal wetlands requires periodic data on the boundaries, extent, and condition of the wetlands. In many states, wetlands are defined wholly, or in combination with other criteria, by the presence of particular emergent halophytic plants. Many important characteristics of the wetlands ecosystem are related directly to the production of emergent plant material or may be inferred from knowledge of the distribution of emergent plant species. Remote-sensing techniques have been applied to mapping of the distribution of wetland vegetation but not to quantitative evaluation of the condition of that vegetation.Recent research in the tidal wetlands of Delaware and elsewhere has shown that spectral canopy reflectance properties can be quantitatively related to the emergent green biomass ofSpartina alterniflora (salt marsh cord grass) throughout the peak growing season (April through September, in Delaware). Periodic measurements of this parameter could be applied to calculations of net aerial primary productivity for large areas ofS. alterniflora marsh in which conventional harvest techniques may be prohibitively time consuming. The method is species specific and, therefore, requires accurate discrimination ofS. alterniflora from other vegetation types. Observed seasonal changes in species spectral signatures are shown to have potential for improving multispectral categorization of tidal wetland vegetation types.     

Ammonia emissions from surface flow and subsurface flow constructed wetlands treating dairy wastewater

Agricultural wastewater treatment is important for maintaining water quality, and constructed wetlands (CW) can be an effective treatment option. However, some of the N that is removed during treatment can be volatilized to the atmosphere as ammonia (NH(3)). This removal pathway is not preferred because it negatively impacts air quality. The objective of this study was to assess NH(3) volatilization from surface flow (SF) and subsurface flow (SSF) CWs. Six CWs (3 SF and 3 SSF; 6.6 m(2) each) were loaded with dairy wastewater ( approximately 300 mg L(-1) total ammoniacal nitrogen, TAN = NH(3)-N + NH(4)(+)-N) in Nova Scotia, Canada. From June through September 2006, volatilization of NH(3) during 12 or 24 h periods was measured using steady-state chambers. No differences (p > 0.1) between daytime and nighttime fluxes were observed, presumably due in part to the constant airflow inside the chambers. Changes in emission rates and variability within and between wetland types coincided with changes in the vegetative canopy (Typha latifolia L.) and temperature. In SSF wetlands, the headspace depth also appeared to affect emissions. Overall, NH(3) emissions from SF wetlands were significantly higher than from SSF wetlands. The maximum flux densities were 974 and 289 mg NH(3)-N m(-2) d(-1) for SF and SSF wetlands, respectively. Both wetland types had similar TAN mass removal. On average, volatilization contributed 9 to 44% of TAN removal in SF and 1 to 18% in SSF wetlands. Results suggest volatilization plays a larger role in N removal from SF wetlands.     

Impacts of freshwater wetlands on water quality: A landscape perspective

In this article, we suggest that a landscape approach might be useful in evaluating the effects of cumulative impacts on freshwater wetlands. The reason for using this approach is that most watersheds contain more than one wetland, and effects on water quality depend on the types of wetlands and their position in the landscape. Riparian areas that border uplands appear to be important sites for nitrogen processing and retention of large sediment particles. Fine particles associated with high concentrations of phosphorus are retained in downstream wetlands, where flow rates are slowed and where the surface water passes through plant litter. Riverine systems also may play an important role in processing nutrients, primarily during flooding events. Lacustrine wetlands appear to have the least impact on water quality, due to the small ratio of vegetated surface to open water. Examples are given of changes that occurred when the hydrology of a Maryland floodplain was altered.     

Freshwater Wetland dynamics in South Kingstown,Rhode Island, 1939–1972

The extent and causes of changes in the fresh-water wetlands of South Kingstown, Rhode Island were determined through field work and through the analysis of panchromatic aerial photographs taken in 1939 and 1972. During this period, there was a net loss of 0.9 percent of the total area (2345.2 ha) of wetland present in 1939. Highway construction and residential development accounted for most of this loss. Approximately 17 percent of the wetland present in 1939 had changed sufficiently by 1972 to warrant reclassification. Plant succession alone accounted for 57 percent of the changes in wetland types, while man's activities were influential in 41 percent of the cases. Ninety-two percent of the natural changes in wetland types was progressive, while 58 percent of the changes induced by man and undetermined causes was retrogressive. Man's major role was to alter the water regimes and vegetation of wetlands. There was a decrease in wetland diversity as the most abundant type, wooded swamp, grew in area while the abundance of shallow marshes, meadows, and shrub swamps declined. A knowledge of wetland dynamics is essential in the management of wetlands for a diversity of wildlife and other natural values.     

Use of created cattail (Typha) wetlands in mitigation strategies

In order to balance pressures for land-use development with protection of wetland resources, artificial wetlands have been constructed in an effort to replace lost ecosystems. Despite its regulatory appeal and prominent role in current mitigation strategies, it is unclear whether or not created systems actually compensate for lost wetland resources. Mitigation predictions that rely on artificial wetlands must be analyzed critically in terms of their efficacy. Destruction of wetlands due to burial by coal fly ash at a municipal landfill in Danvers, Massachusetts, USA, provided an opportunity to compare resulting growth of created cattail (Typha) marshes with natural wetland areas. Once the appropriate cattail species was identified for growth under disturbed landfill conditions, two types of artificial wetlands were constructed. The two systems differed in their hydrologic attributes: while one had a surface water flow characteristic of most cattail wetlands, the second system mimicked soil and water conditions found in naturally occurring floating cattail marshes. Comparison of plant growth measurements for two years from the artificial systems with published values for natural cattail marshes revealed similar structure and growth patterns. Experiments are now in progress to investigate the ability of created cattail marshes to remove and accumulate heavy metals from polluted landfill leachate. Research of the type reported here must be pursued aggressively in order to document the performance of artificial wetlands in terms of plant structure and wetland functions. Such research should allow us to start to evaluate whether artificial systems actually compensate for lost wetlands by performing similar functions and providing the concomitant public benefits.     

Strategies for assessing the cumulative effects of wetland alteration on water quality

Assessment of cumulative impacts on wetlands can benefit by recognizing three fundamental wetland categories: basin, riverine, and fringe. The geomorphological settings of these categories have relevance for water quality.Basin, or depressional, wetlands are located in headwater areas, and capture runoff from small areas. Thus, they are normally sources of water with low elemental concentration. Although basin wetlands normally possess a high capacity for assimilating nutrients, there may be little opportunity for this to happen if the catchment area is small and little water flows through them.Riverine wetlands, in contrast, interface extensively with uplands. It has been demonstrated that both the capacity and the opportunity for altering water quality are high in riverine wetlands.Fringe wetlands are very small in comparison with the large bodies of water that flush them. Biogeochemical influences tend to be local, rather than having a measurable effect on the larger body of water. Consequently, the function of these wetlands for critical habitat may warrant protection from high nutrient levels and toxins, rather than expecting them to assume an assimilatory role.The relative proportion of these wetland types within a watershed, and their status relative to past impacts can be used to develop strategies for wetland protection. Past impacts on wetlands, however, are not likely to be clearly revealed in water quality records from monitoring studies, either because records are too short or because too many variables other than wetland impacts affect water quality. It is suggested that hydrologic records be used to reconstruct historical hydroperiods in wetlands for comparison with current, altered conditions. Changes in hydroperiod imply changes in wetland function, especially for biogeochemical processes in sediments. Hydroperiod is potentially a more sensitive index of wetland function than surface areas obtained from aerial photographs. Identification of forested wetlands through photointerpretation relies on vegetation that may remain intact for decades after drainage. Finally, the depositional environment of wetlands is a landscape characteristic that has not been carefully evaluated nor fully appreciated. Impacts that reverse depositional tendencies also may accelerate rates of change, causing wetlands to be large net exporters rather than modest net importers. Increases in rates as well as direction can cause stocks of materials, accumulated over centuries in wetland sediments, to be lost within decades, resulting in nutrient loading to downstream aquatic ecosystems.