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71.
湿地生态系统累积影响评价研究 总被引:2,自引:0,他引:2
定量分析湿地生态系统的累积环境影响,确定所要评价的功能,然后定量分析影响该功能的各种累积方式,将湿地生态系统的累积方式分为四种方式进行描述,对各种干扰活动的相互关系予以定性并进行量化,探讨湿地生态系统累积影响评价的步骤,有助于湿地生态系统CEA方法体系的建立与完善. 相似文献
72.
松北区湿地位于哈尔滨市松北区管辖范围内,其湿地面积大,分布广,物种多,环境好,成为哈尔滨市重要的湿地群。尽管地方政府一直致力于湿地保护工作,但随着城市开发建设,松北区的湿地环境也不可避免地遭受不同程度的破坏。围绕松北区湿地的保护开发,建议完善湿地保护开发规划,加强综合执法,提升松北湿地生态旅游水平,加强湿地环境监测。 相似文献
73.
在抚仙湖北岸构建复合型人工湿地污水处理系统,对窑泥沟入湖河道污水中氮的去除效果进行了试验研究,结果表明,系统水力负荷年平均为37mm/d,氮负荷年平均为3.315g/m2·d,对污水中NOx、NH+4、TON和TN去除率年平均分别为62.7%、53.8%、62.4%和57.5%. 相似文献
74.
通过在所构建的3组垂直流人工湿地(CW1、CW2、CW3)中添加不同ρ(DOC)(0、14、28 mg/L,DOC为溶解性有机碳)的美人蕉根系浸出液来模拟根系分泌物浓度变化,考察其对2种SEs(steroidal estrogens,类固醇雌激素)去除效果的影响. 结果表明:①虽然根系浸出液和根系分泌物中的ρ(DOC)存在差异,但二者成分比例类似,均含有多种小分子化合物(如氨基酸、多糖、有机酸、脂肪酸、醇、烷等),并且甘油含量均为最高. ②各组湿地对SEs的去除率表现为CW2>CW3≈CW1,CW2对E1(Estrone,雌酮)、EE2(17α-Ethinylestradiol,17α-乙炔基雌二醇)的去除率最高可分别达到86.9%、72.7%. ③各组湿地全细菌和AOB(ammonia oxidizing bacteria, 氨氧化细菌)平均密度大小表现为CW3>CW2>CW1,NOB(nitrite oxidation bacteria, 亚硝酸氧化细菌)平均密度大小表现为CW2>CW3>CW1,DNB(denitrifying bacteria, 反硝化细菌)平均密度大小表现为CW3>CW1≈CW2,各组湿地基质上生物膜的脱氢酶活性表现为CW2>CW1>CW3.研究显示,适量添加根系浸出液有利于SEs的去除,但根系浸出液中ρ(DOC)过高,可能会对植物根系和特定根系微生物(如NOB)的生长造成毒害作用,并抑制微生物活性,从而影响SEs的去除效果. 相似文献
75.
针对连续流人工湿地脱氮效果差、占地面积大、冬季效能低的问题,以提高人工湿地冬季低温运行效能、减小人工湿地占地面积为目标,在前期序批式深床人工湿地研究基础上,重点考察其冬季低温条件下的处理效能。结果表明,温度对序批式深床人工湿地效能影响显著,8~10℃下城镇污水进水COD、NH_4~+-N和TN质量浓度为261mg/L、60 mg/L和70 mg/L时,各自平均去除率分别为72.6%、36.7%和40.2%,较20~25℃时分别下降9.8%、15.4%和10.6%;水温8-10℃时,2级序批式深床人工湿地系统COD、NH_4~+-N和TN去除率分别为95.1%、74.7%和78.7%,较单级系统的72.0%、38.9%和41.1%分别提高了23.1%、35.8%和37.6%。 相似文献
76.
77.
Feng Liu Lei Sun Jinbao Wan Liang Shen Yanhong Yu Lingling Hu Ying Zhou 《环境科学学报(英文版)》2020,32(3):252-263
Plants constitute a major element of constructed wetlands(CWs).In this study,a coupled system comprising an integrated vertical flow CW(IVCW) and a microbial fuel cell(MFC) for swine wastewater tre atment was developed to research the effects of macrophytes commonly employed in CWs,Canna indica,Acorus calamus,and Ipomoea aquatica,on decontamination and electricity production in the system.Because of the different root types and amounts of oxygen released by the roots,the rates of chemical oxygen demand(COD) and ammonium nitrogen(NH_4~+-N) removal from the swine wastewater differed as well.In the unplanted,Canna indica,Acorus calamus,and Ipomoea aquatica systems,the COD removal rates were 80.20%,88.07%,84.70%,and 82.20%,respectively,and the NH_4~+-N removal rates were 49.96%,75.02%,70.25%,and 68.47%,respectively.The decontamination capability of the Canna indica system was better than those of the other systems.The average output voltages were 520±42,715±20,660±27,and 752±26 mV for the unplanted,Canna indica,Acorus calamus,and Ipomoea aquatica systems,respectively,and the maximum power densities were 0.2230,0.4136,0.3614,and0.4964 W/m~3,respectively.Ipomoea aquatica had the largest effect on bioelectricity generation promotion.In addition,electrochemically active bacteria,Geobacter and Desulfuromonas,were detected in the anodic biofilm by high-throughput sequencing analysis,and Comamonas(Proteobacteria),which is widely found in MFCs,was also detected in the anodic biofilm.These results confirmed the important role of plants in IVCW-MFCs. 相似文献
78.
YAN Li Ryuhei Inamori GUI Ping XU Kai-qin KONG Hai-nan Masatoshi Matsurnur Yuhei Inamori 《环境科学学报(英文版)》2005,17(6):993-997
A molecular biology method, fluorescent in situ hybridization(FISH), in which the pre-treatment was improved in allusion to the media of the constructed wetlands(CW), e.g. the soil and the grit, was used to investigate the vertical distribution characteristics of ammonia-oxidizing bacteria(AOB) quantity and the relation with oxidation-reduction potential(ORP) in the Typha latifolia constructed wetlands under three different Ioadings in summer from May to September. Results showed that the quantity of the AOB decreased in the Typha latifolia CW with the increase of vertical depth. However, the AOB quantity was 2-4 times the quantity of the control in the root area. Additionally, ORP in the rhizosphere was found to be higher than other areas, which showed that Typha latifolia CW was in an aerobic state in summer when using simulated non-point sewage at the rural area of Taihu Lake in China and small town combined sewage. 相似文献
79.
研究了湿地重建过程中植物、土壤和水质的动态变化特征.湿地重建2 a后植物种类增加了11种,芦苇、菖蒲和香蒲3种植物的高度、生物量在第2个生长季明显高于第1个生长季节,植物生物量分别增加到原来的13、1.5和1.4倍.湿地种植区土壤有机质总体上是降低的,土壤全氮含量从1?500 mg/kg降低到850 mg/kg(p<0.01),土壤全磷在试验期间略有增加.对重建湿地12种水质指标分析表明,夏季湿地出口源水溶解氧高于进口源水,出口源水总氮、叶绿素a、藻类计数3种水质指标均低于进口源水,说明重建湿地水质在夏季出口源水优于进口源水,水质得到改善.研究表明,湿地植物群落重建成功,生物多样性增加,重建湿地在改善和保持源水水质方面发挥了一定的作用. 相似文献
80.
L.L. Smith A.L. Subalusky C.L. Atkinson J.E. Earl D.M. Mushet D.E. Scott S.L. Lance S.A. Johnson 《Journal of the American Water Resources Association》2019,55(2):334-353
Many species that inhabit seasonally ponded wetlands also rely on surrounding upland habitats and nearby aquatic ecosystems for resources to support life stages and to maintain viable populations. Understanding biological connectivity among these habitats is critical to ensure that landscapes are protected at appropriate scales to conserve species and ecosystem function. Biological connectivity occurs across a range of spatial and temporal scales. For example, at annual time scales many organisms move between seasonal wetlands and adjacent terrestrial habitats as they undergo life‐stage transitions; at generational time scales, individuals may disperse among nearby wetlands; and at multigenerational scales, there can be gene flow across large portions of a species’ range. The scale of biological connectivity may also vary among species. Larger bodied or more vagile species can connect a matrix of seasonally ponded wetlands, streams, lakes, and surrounding terrestrial habitats on a seasonal or annual basis. Measuring biological connectivity at different spatial and temporal scales remains a challenge. Here we review environmental and biological factors that drive biological connectivity, discuss implications of biological connectivity for animal populations and ecosystem processes, and provide examples illustrating the range of spatial and temporal scales across which biological connectivity occurs in seasonal wetlands. 相似文献