Ciliate communities in a constructed mangrove wetland for wastewater treatment     

Qing-Hua Chen  Nora Fung-Yee Tam  Paul K.S. Shin  Siu-Giu Cheung  Run-Lin Xu 《Marine pollution bulletin》2009,58(5):711-719

In wetlands constructed for treating municipal and industrial wastewater, including mangroves, the effect of wastewater discharged on the substrate has often been neglected. Ciliates, an important group of protozoa, are sensitive to pollutants and any changes in ciliate diversity and community structure reflects the habitat quality. The ciliate communities at six sections along a constructed mangrove belt (33 m in length) planted with Aegicerascorniculatum were investigated in Shenzhen, South China. In all samples collected in both rainy and dry seasons, 183 ciliate species were observed. Most species (56%) were free-swimming forms, while only 10.8% were sessile ciliates. The abundance and species number of ciliates were both found to decrease from the anterior (the wastewater inlet) to the posterior (the outlet) parts of the wetland belt, indicating that organic matter and bacteria in wastewater, which served as food for most ciliates, were gradually removed by the constructed wetland. The r/K (number of r- and K-selected species) ratios at the six sections were relatively small, between 0.2 and 0.4, whereas the C/P (abundance of colpodids and polyhymenophorans) quotient at some sections was higher than 1. These results indicate that although most of the environments along the constructed wetland belt were not stressful for ciliate communities, there were habitats that favored colpodids in high abundances.  相似文献   

Biogeochemical controls of arsenic occurrence and mobility in the Indian Sundarban mangrove ecosystem   总被引：1，自引：0，他引：1  

S.K. Mandal  D. Ganguly  T.K. Jana 《Marine pollution bulletin》2009,58(5):652-657

This study aims to investigate the control of arsenic distribution by biogeochemical processes in the Indian Sundarban mangrove ecosystem and the importance of this ecosystem as an arsenic source for surrounding coastal water. The As(V)/As(III) ratio was found to be significantly lower in both surface and pore waters compared to sea water, which could be attributed to biogeochemical interconversion of these arsenic forms. The biological uptake of arsenic due to primary and benthic production occurs during the post-monsoon season, and is followed by the release of arsenic during the biochemical degradation and dissolution of plankton in the pre-monsoon season. These results suggest that arsenic is immobilized during incorporation into the arsenic-bearing initial phase, and unlikely to be released into pore water until the complete microbial degradation of arsenic-bearing organic compounds.  相似文献   

Interstitial water and hydrochemistry of a mangrove forest and adjoining water system, south west coast of India   总被引：1，自引：0，他引：1  

K. A. Bava  P. Seralathan 《Environmental Geology》1999,38(1):47-52

 Eh, pH, salinity, total alkalinity, dissolved O₂, NO₂ ^–, PO₄ ^–3, SiO₂ and NH₄ ⁺ of waters from a mangrove forest, an estuary and a creek connecting the mangrove forest and the estuary have been measured. Further, the chemistry of interstitial waters of surficial and core sediments from the mangrove forest have been analyzed for the above parameters, except dissolved oxygen. To understand the flux of nutrients from the mangrove forest to the adjoining estuary, creek waters were monitored during tidal phases. PO₄ ^–3, SiO₂ and NH₄ ⁺ were found to be at elevated levels in mangrove waters whereas NO₂ ^– shows no variation compared to the estuary. Dissolved O₂ is low in mangrove waters. PO₄ ^–3, NH₄ ⁺ and SiO₂ are several times higher in interstitial waters than in overlying waters. Several fold enrichment of PO₄ ^–3, NH₄ ⁺ and, to some extent, SiO₂ were measured in creek waters during ebbing relative to flooding, indicating that mangroves act as a perennial source for the above nutrients. Received: 26 May 1998 · Accepted: 21 July 1998  相似文献   

Environmental geochemistry of the Pichavaram mangrove ecosystem (tropical), southeast coast of India   总被引：3，自引：0，他引：3  

A. L. Ramanathan  V. Subramanian  R. Ramesh  S. Chidambaram  A. James 《Environmental Geology》1999,37(3):223-233

 Spatial and temporal geochemical variations of various parameters in the water and sediment of a relatively small mangrove situated on the southeast coast of India were examined in detail for the first time. The water quality generally reflects the impact of seawater and the Vellar estuary (mixing effect) aided by evaporation and in situ biological productivity. The depletion and fluctuation of dissolved silica are controlled by biological processes. Nitrate and phosphate are contributed by fertilizer input from adjoining agriculture fields. Total suspended matter (TSM) shows an erratic range and trend due to deforestation and resuspension processes. Sand and silt constitute 70–90% of the sediments. Statistical analysis of the sediments shows the prevalence of a moderately high-energy environment with very effective winnowing activity. Organic matter content is higher in the mangrove sediments in comparison to adjacent estuaries. Water and sediment show fluctuations in their chemical concentration, but no specific trends could be identified. Heavy metals are also enriched in the mangrove sediments, indicating their unique chemical behavior and the existence of trapping mechanisms. Factor analysis and correlation analysis of water and sediments show the complexity of the system and the multitude of contributing sources. The core sediment chemistry suggests the depletion of metal input due to the damming of the detrital inputs. The Pichavaram mangrove seems to be relatively unpolluted, since the anthropogenic signal observed is small and acts as a sink for heavy metals contributed from a multitude of sources without an adverse effect. Received: 5 November 1997 · Accepted: 30 March 1998  相似文献   

河口红树林湿地CH₄通量的日变化研究   总被引：10，自引：0，他引：10  

叶勇  卢昌义  林鹏  谭风仪  黄玉山 《海洋学报》2000,22(3):103-109

甲烷(CH₄)是大气中除CO₂外最为丰富的含碳组分,其浓度以每年0.7%-1.1%的速率递增[1,2].尽管大气CH₄含量仅为CO₂的二百分之一,但却对预计的全球变暖约有20%的贡献率,而CO₂的贡献率约为50%[3,4],由这些数据推算得一个分子的CH₄比一个分子的CO₂(目前最重要的温室气体)的增暖潜值高约80倍.很多研究者对全球大气CH₄的预算结果均表明,湿地是大气CH₄最重要的生物源[5,6],约占全球CH₄源的40%～50%[7].湿地CH₄通量的日变化研究是正确估算大时间尺度下CH₄排放量(如平均年排放量和季节排放量)的基础,因而具有相当的重要性.  相似文献   

海南红树林湿地沉积物耗氧及其相关因素     

马晓磊  徐继荣  殷建平  张德民  高华生  孙文凭 《海洋与湖沼》2010,41(6):941-946

于2009年8月在海南省东寨港、亚龙湾青梅港和三亚河口红树林区,分别采用自行研制的沉积物耗氧量(Sediment oxygen demand,SOD)测定装置,对红树林湿地SOD和相关环境因子进行研究。结果表明,红树林湿地沉积物耗氧主要分为2个阶段,即瞬时耗氧阶段和渐缓耗氧阶段。3个站位的SOD值范围为102.2-157.7mg/(m2·h),其中瞬时耗氧占23.3%-45.5%。SOD与沉积物中的硫化物含量及上覆水中的化学耗氧量(Chemical oxygen demand,COD)、NH4+浓度有显著的相关性。研究结果表明,红树林湿地沉积物能对其上覆水释放有机物并消耗水体中的溶解氧,使水质变差,因此,用红树林湿地处理城市污水可能导致生态恶化。  相似文献   

红树林湿地生态功能及其价值研究文献学分析   总被引：1，自引：0，他引：1  

生农  辛琨  廖宝文 《湿地科学与管理》2021,17(1):47-50

红树林生长于海洋与陆地的动态交界面,特殊的生长环境赋予其独特而强大的生态功能。采用文献检索法和追溯法分析国内外红树林湿地生态功能研究的进展和现状,将相关研究归纳为“综合性研究”与“单项生态功能研究”两种,“综合性研究”关注生物多样性保持与净化功能,“单项生态功能研究”较重视旅游文化价值与固碳价值。红树林生态功能价值评价方法的比较表明,参数法、市场价格法、替代法更为常用,支付意愿法和生态模型法较少。其中,参数法简单易用但可靠性低,市场价格法在其适用范围内效果很好但适用范围窄,替代法使用的替代标准合理选取不易,支付意愿法简便易行但主观性较强,生态模型法结果最稳定,是红树林生态功能价值研究的发展趋势,但存在基础数据不足的问题。目前,国内外红树林生态功能价值研究存在缺乏生态整体观念和基础生态数据以及评估方法不完善等问题,展望了红树林湿地研究发展趋势,为红树林生态功能及其价值评价研究提供参考依据。  相似文献   

红树林混合发酵产氢菌群中梭菌属Fe-氢酶基因(hydA)的克隆及序列分析   总被引：1，自引：1，他引：0  

朱大玲  王广策  潘光华  乔洪金  才金玲 《海洋与湖沼》2009,40(4):518-524

采用间歇产气试验方法对红树林淤泥中的混合菌群进行产氢菌群富集,并对混合产氢菌群发酵产氢过程中发酵液的pH值和氧化还原电位(ORP)的变化进行分析.此外,在产氢速率最高时段,发酵液中菌群经过常规的基因组提取,分别采用通用的梭菌属Fe-氢酶基因和16S rRNA基因引物进行PCR扩增,扩增产物经变性梯度凝胶电泳(DGGE)分析.结果发现产氢菌群中至少有6种,而Fe-氢酶基因只含有一种.将Fe-氢酶基因的扩增片段切胶纯化之后,经PCR重新扩增、纯化,克隆测序.NCBI序列比对结果表明,该片段序列与产气荚膜梭菌Fe-氢酶基因的序列相似性达99%.根据已知产气英膜梭菌Fe-氢酶基因序列设计引物,经两轮PCR扩增获得Fe-氢酶基因全序列.混合菌群中Fe-氢酶基因GenBank数据库的登录号为EU590683.此外,采用Bioedit和Mega2软件构建了Fe-氢酶的NJ系统进化树,结果表明该Fe-氢酶基因与产气荚膜梭菌(Clostridium perfringens)聚为一类.推测的氨基酸序列与产气英膜梭菌的相应序列相似性达97%-99%.PfamHMM结构域查找结果发现,此氢酶含有五个结构域,分别为1个2Fe-2S铁硫簇结合区域、2个4Fe-4S结合区域、Fe-氢酶大亚基和Fe-氢酶小亚基.  相似文献   

Spatial and seasonal variations of fish assemblages in mangrove creek systems in Zanzibar (Tanzania)     

Augustine W. Mwandya  Martin Gullström  Mathias H. Andersson  Marcus C. Öhman  Yunus D. Mgaya  Ian Bryceson 《Estuarine, Coastal and Shelf Science》2010

Spatial and seasonal variations of fish assemblage composition were studied in three non-estuarine mangrove creeks of Zanzibar (Tanzania). Fish were collected monthly for one year at three sites (lower, intermediate and upper reaches) in each creek using a seine net (each haul covering 170 m²). Density, species number and diversity of fish were all higher at sites with dense cover of macrophytes (seagrass and macroalgae) than over unvegetated sandy sites. In general, fish assemblages mainly comprised juveniles of a few abundant taxa, e.g. Mugil cephalus, Mugilidae spp. and Leiognathus equulus at sites with mud substratum and Gerres oyena, Lethrinus harak and Sillago sihama at sites dominated by macrophytes. Multivariate analyses revealed significant separations in fish assemblage composition within the two creeks where the bottom substratum differed among sites. Overall, season seemed to have little effect on density, species number, diversity index (H′) and assemblage structure of fish. Water condition variables were also relatively stable across the season, although a short-term fluctuation primarily induced by decreased salinity, occurred during the heavy rains in April and May. Fish assemblage structure was not significantly affected by any of the abiotic factors tested. However, significant regressions were found between the other fish variables and environmental variables, but since these associations were mostly species-specific and generally inconsistent, we suggest that the overall distribution patterns of fish were mainly an effect of particular substrate preferences of fish species rather than contemporary water conditions.  相似文献   

木榄胚轴萌发及幼苗生长与生理对水渍和底质条件的响应   总被引：1，自引：0，他引：1  

叶勇  刘美龄  卢昌义  谭凤仪 《海洋与湖沼》2007,38(1):84-90

采用模拟半日潮系统研究了水渍和底质条件对红树植物木榄(Bruguieragymnorrhiza)的影响。水位上升和淹水时间延长导致红树林底质的酸化,且壤质底质的酸化比沙质底质严重;对木榄的萌苗速度无显著影响;促进木榄的早期生长,尤其是导致最初2个月茎高生长的增加,但后2个月木榄的相对生长率受抑制;地下部/地上部生物量比值下降,沙质底质中尤为如此;粗根比例明显增加;叶绿素含量增加,叶绿素a/b比值无显著影响;叶面积减少;壤质底质上生长植株的叶片气孔密度增加,沙质底质无显著变化;根N含量无显著变化,P含量显著增加。  相似文献