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1.
为描述草海湿地DOM(dissolved organic matter,溶解性有机物)荧光特征,探究其对PFASs(per-and polyfluoroalkyl substances,全氟及多氟化合物)环境行为造成的影响,利用超高效液相色谱-质谱联用技术和三维荧光光谱技术,结合平行因子分析,开展DOM光谱学特性研究,分析ρ(DOM)与ρ(PFASs)的相关关系.结果表明:①草海湿地中共解析出3类4种荧光组分,分别为类腐殖酸[λEx(360 nm)/λEm(450 nm)]、长波段腐殖质[λEx(400 nm)/λEm(510 nm)]、类富里酸[λEx(330 nm)/λEm(400 nm)]和类色氨酸[λEx(280 nm)/λEm(350 nm)],贡献率分别为48.6%、23.6%、22.9%和4.9%,其中类腐殖质总贡献率高达72.2%.在农业生产和人类活动的影响下,总荧光强度大致呈现从入湖区向出湖区逐渐降低、湖心区略高的趋势.②在草海湿地表层水中共检出了12种PFASs,ρ(PFASs)为233.18 ng/L,每种平均值为19.43 ng/L,PFBA(perfluorobutanoic acid,全氟丁酸)是主要污染物;草海湿地入湖区点源影响特征明显,生活污水和农业生产用水是主要的潜在污染源.③相关性分析结果显示,各荧光组分含量均与ρ(PFBS)(potassium perfluorobutanesulfonate,全氟丁烷磺酸)负相关;类色氨酸含量与ρ(PFHpA)(perfluororoheptanoic acid,全氟庚酸)负相关,与ρ(PFTriDA)(perfluorotrideanoic acid,全氟十三酸)则显著正相关.研究显示,草海湿地水体腐殖化程度高,外源特征明显,共检出12种PFASs,初步揭示了草海湿地水环境中ρ(DOM)与ρ(PFASs)的相关关系,其受水体性质及化合物结构等差异的影响,有待进一步开展深入研究.   相似文献   
2.
卧龙湖是辽宁西北半干旱区向中部平原湿润区过渡的生态敏感带,本文介绍了卧龙湖的历史与现状,分析了存在的主要问题,并从微观角度提出了保护卧龙湖湿地的具体措施。  相似文献   
3.
上海地区湿地生态旅游资源研究   总被引:6,自引:0,他引:6  
国峰  韦鹤平 《四川环境》2003,22(5):45-47,57
从国内外湿地研究进展中发现,湿地景观资源及其管理对策研究得到人们越来越广泛的重视。上海市湿地面积广阔,占全市海拔-5m以上总面积9123km^2的65.67%,同时具有景观多样性和生物物种多样性。丰富的湿地资源为上海市提供了广阔的绿地空间,成为宝贵的旅游资源。本文对上海市的湿地景观资源进行了细致的分析,并介绍了其开发和利用现状,在此基础上提出了规划设想和几点建议。  相似文献   
4.
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.  相似文献   
5.
中国湿地现状综述   总被引:9,自引:0,他引:9  
湿地是重要的自然资源,对人类生存起着重要作用。本文综述了湿地的含义、功能与 价值、中国湿地的特点与现状,以促进中国湿地的可持续发展与利用。  相似文献   
6.
The performance of a wetland system in treating lead (Pb)/zinc (Zn) mine drainage was evaluated by using the polyurethane foam unit (PFU) microbial community (method), which has been adopted by China as a standardized procedure for monitoring water quality. The wetland system consisted of four cells with three dominant plants: Typha latifolia, Phragmites australis and Paspalum distichum. Physicochemical characteristics [pH, EC, content of total suspended solid (TSS) and metals (Pb, Zn, Cd, and Cu)] and PFU microbial community in water samples had been investigated from seven sampling sites. The results indicated that the concentrations of Pb, Zn, Cd, Cu, and TSS in the mine drainage were gradually reduced from the inlet to the outlet of the wetland system and 99%, 98%, 75%, 83%, and 68% of these metals and TSS respectively, had been reduced in concentration after the drainage passed through the wetland system. A total of 105 protozoan species were identified, the number of protozoa species and the diversity index (DI) gradually increased, while the heterotrophic index (HI) gradually decreased from the inlet to the outlet of the wetland system. The results indicated that DI, HI, and total number species of protozoa could be used as biological indicators indicating the improvement of water quality.  相似文献   
7.
Hydrogeomorphic (HGM) functional assessment models were used to assess whether function in created wetlands of two ages (1 year old and >12 years old) was equivalent to that of natural (reference) mainstem floodplain wetlands. Reference wetlands scored higher than both created age classes for providing energy dissipation and short-term surface water storage. Reference wetlands scored higher in maintaining native plant community and structure than 1-year-old sites, and 12-year-old wetlands scored higher than reference sites for providing vertebrate habitat structure. Analysis of individual model variables showed that reference wetlands had greater vegetative biomass and higher soil organic matter content than both created wetland age classes. Created wetlands were farther from natural wetlands and had smaller mean forest patch sizes within a 1-km-radius circle around the site than did the reference sites, indicating less hydrologic connectivity. Created wetlands also had less microtopographic variation than reference wetlands. The 1-year-old created sites were placed in landscape settings with greater land use diversity and road density than reference sites. The 12-year-old sites had a higher gradient and a higher percentage of their surrounding area in urban land use. These results show that the created wetlands were significantly structurally different (if not functionally so) from reference wetlands even after 12 years. The most profound differences were in hydrology and the characteristics of the surrounding landscape. More attention needs to be focused on placing created wetlands in appropriate settings to encourage proper hydrodynamics, eliminate habitat fragmentation, and minimize the effects of stressors to the site.  相似文献   
8.
黄河口湿地土壤中正构烷烃分子指标及物源指示意义   总被引:5,自引:4,他引:1  
姚鹏  尹红珍  姚庆祯  陈洪涛  刘月良 《环境科学》2012,33(10):3457-3465
对黄河口湿地表层土壤中的总有机碳、正构烷烃等进行了分析,计算了正构烷烃分子指标,探讨了其物源指示意义,并对不同采样区域和采样时间的结果进行了比较.结果表明,黄河口湿地土壤中正构烷烃以高碳奇数烷烃(C25~C33)为主,说明土壤中有机质主要来自于陆地高等植物,而样品中未分离混合物的存在表明土壤可能受到了油类污染.土壤中总的正构烷烃含量有明显的时间和区域差异,总的变化范围在0.57~3.90μg.g-1.在2009年4月(枯水期)总的正构烷烃含量相对6月(调水调沙期间)要高,以黄河口湿地核心恢复区最高,其次是黄河入海前最后一个浮桥下方的黄河北岸,最后是黄河故道区域,而6月的变化趋势与此相反.这一变化趋势与总有机碳是一致的,而与中值粒径的变化趋势相反,反映了两个不同的采样时间水环境条件的差异.基于正构烷烃的分子指标,如平均链长ACL、奇偶优势度OEP、烷烃指数AI、碳优势指数CPI和陆海比TAR等表明黄河口湿地土壤的有机质的成熟度较低,有较强的陆源高等植物输入优势,且主要来自于草本植物.与其他指标相比,陆海比指标TAR更好地反映了水环境条件的变化.  相似文献   
9.
黄河三角洲碱蓬湿地土壤有机碳及其组分分布特征   总被引:5,自引:2,他引:3  
董洪芳  于君宝  管博 《环境科学》2013,34(1):288-292
应用物理分组方法研究了黄河三角洲典型碱蓬湿地土壤有机碳及其组分分布特征.结果表明,研究区土壤重组有机碳是土壤有机碳的主要组成部分,土壤重组有机碳含量、土壤颗粒有机碳含量与土壤总有机碳含量都显著正相关.研究区土壤轻组组分比例和含量范围分别在0.008%~0.15%和0.10~0.40 g·kg-1,颗粒有机碳分配比例范围为8.83%~30.58%,说明黄河三角洲碱蓬湿地土壤有机碳中非保护性组分较低,碳库相对稳定.  相似文献   
10.
湿地是自然界生物多样性最丰富的生态景观和人类最重要的生存环境之一。敦煌阳关湿地因其特殊的地理环境形成了其明显的特点。人为活动对该湿地资源的过度开发及不合理利用,加之全球气候变化的影响,湿地面临着环境恶化、资源枯竭、生态退化等的严重威胁。这也对该湿地功能的发挥和可持续利用造成了非常大的影响。本文以敦煌阳关湿地为研究对象,分析了阳关自然保护区内湿地保护面临的问题,并提出科学合理规划湿地、开展湿地资源监测、湿地保护与生态旅游开发的协调发展等一系列措施。本文对甘肃敦煌阳关国家级自然保护区湿地资源的保护和可持续发展有一定的参考意义。  相似文献   
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