Ciliate Abundance Research Articles

Plankton ciliate community responses to different aquatic environments in Nan'ao Island, a representative mariculture base in the South China Sea

The temporal variation and spatial distribution of plankton ciliate communities were investigated in Shen’ao Bay, South China Sea. In all, 35 species belonging to 17 genera and 7 orders were identified. The number of ciliate species was lower in spring than in summer, whereas ciliate abundance was higher in spring than in summer. Spatially, the number of ciliate species and ciliate abundance were higher in the oyster–algae mixed culture area and non-aquaculture area, and lower in the caged fish culture area. Multivariate and univariate analyses demonstrated that ciliate communities were associated with environmental factors (e.g. temperature, chlorophyll (Chl)-a, nutrient levels). In addition, two dominant species, namely Mesodinium rubrum and Tintinnopsis beroidea, were significantly positively correlated with Chl-a. Three dominant species, namely Strombidium globosaneum, Tintinnopsis minuta and Strombidium conicum, showed more sensitivity to dissolved oxygen, pH and chemical oxygen demand, whereas Tintinnopsis parvula and Tintinnopsis chinglanensis were significantly related to NO2–. Ciliate species diversity, species evenness and species richness were higher in the oyster–algae mixed culture area and non-aquaculture area and lower in the caged fish culture area. Therefore, the results of this study suggest that the ciliate community is significantly correlated with its aquatic habitat and the dominant species can be considered a favourable bioindicator of the marine water environment.

The influences of nitrogen form and zooplankton grazing on phytoplankton assemblages in two coastal southeastern systems

AbstractCoastal environments are vulnerable to land development due to human population growth that has increased nitrogen and phosphorus loading into receiving estuaries. As a result, phytoplankton blooms have proliferated as “bottom‐up” (resource) processes outweigh “top‐down” (removals). This study investigated phytoplankton biomass and assemblage regulation by both N‐form (ammonium, nitrate, urea) and zooplankton at two southeastern United States estuaries (the urban Charleston Harbor and less‐developed Ashepoo‐Combahee‐Edisto Basin) with contrasting land cover patterns through in situ nutrient addition bioassays (spring and summer, 2015–2016) and dilution experiments (summer 2016). Phytoplankton responses to N exhibited no clear patterns during spring. By comparison, summer chlorophyll a (Chl a) increases were significant (p < 0.05) in response to all provided N forms, and diatoms contributed most to total biovolume with biovolume increases higher at the more developed site per estuary. Phytoplankton Chl a and biovolume were generally greatest when all nutrients were added in combination, but nitrate added alone frequently elicited the lowest response. Ciliate abundances were high at most sites with lower mesozooplankton abundances. Accordingly, microzooplankton grazing rates were highest for < 5 μm and < 20 μm Chl a fractions, often corresponding with the highest phytoplankton growth rates. Ciliate abundances tracked Chl a during bioassays, highlighting their role as important biomass controls in these estuaries. Results can be used to inform nutrient management decisions, as continued development will increase nutrient loading to developed and developing systems.

Planktonic ciliates in different water masses in open waters near Prydz Bay (East Antarctica) during austral summer, with an emphasis on tintinnid assemblages

Planktonic ciliates are important microzooplankton in pelagic ecosystems. Previous studies in Antarctic waters have only investigated ciliate assemblages in different habitats without considering water masses. In this article, we report the characteristics of ciliate assemblages in different water masses in open waters near Prydz Bay (East Antarctica) during austral summer. Three water masses were identified according to temperature and salinity: Summer Surface Water (SSW), Winter Water (WW), and Circumpolar Deep Water (CDW). SSW was further divided into SSWChl a 3 mg m−3) and SSWChl a WW > CDW. SSWChl a > 3 had a higher proportion (38.2%) of tintinnids to the total ciliate abundance and larger aloricate ciliates (ciliates in the 10–20 µm size class were 30%) of Southern Ocean endemic tintinnid species in total tintinnid abundance than in other water masses. Each water mass had the following indigenous tintinnid species: SSW, Salpingella sp., Codonellopsis gaussi; WW, Salpingella costata, S. faurei, Cymatocylis affinis/convallaria forma drygalskii, and C. vanhoeffeni. Laackmanniella naviculaefera and C. affinis/convallaria forma cristallina were present at high abundance in both WW and SSWChl a > 3. Upwelling caused discontinuity of the ciliate distribution. Our results will help predict the spatial and temporal variations of ciliate assemblages and other plankton according to the dynamics of water masses in Antarctic waters.

Spatial and inter-annual variability of proto- and metazooplankton during summer around the Kneiss Islands (Tunisia, Central Mediterranean Sea)

We studied the distribution of proto- and metazooplankton coupled with environmental factors in the coast area around Kneiss Islands (Central Mediterranean Sea). Zooplanktonic communities were sampled during summer 2009 and summer 2010 at three stations. Our results showed difference in suspended matter concentrations between summer 2009 (92.88 ± 7.15 mg L−1) and summer 2010 (47.37 ± 23.12 mg L−1). Large variations in the N/P ratio were recorded (6.94–36.76) due to the direct influence of the variability in concentration of both the dissolved inorganic nitrogen and dissolved inorganic phosphate components of the ratio. Ciliates abundance peaked in summer 2009 and was 3 times more abundant than summer 2010. Ciliates community composition was dominated by loricate ciliates (75% of total ciliates) in summer 2009 and naked ciliates (56% of total ciliates) in summer 2010. Copepods were the most abundant metazooplankton present during the entire study period, comprising 30–96% of the total metazooplankton community. Small planktonic copepods reached important abundance, particularly oithonids, were found to largely dominate copepods community in both summer 2009 (Oithona nana, 45% of total copepods) and summer 2010 (Oithona similis, 22% of total copepods). The small planktonic species Paracalanus parvus (54% of total copepods) was abundant during summer 2010. The results also indicate that (1) ciliates abundance was very low, showing a possible predation by copepods and also by heterotrophic dinoflagellates, (2) copepods capable to complete a top-down control on phytoplankton and ciliates, with preference to ciliates more than diatoms of similar size and shape and (3) the resistance of loricate ciliates compared to naked ciliates may be explained by their capacity to escape grazing due to the existence of a protective lorica.

Influence of phosphorus application and water deficit on the soil microbiota of N2‐fixing and non‐N‐fixing tree

AbstractSoil water content and phosphorus availability are important factors that are expected to shape soil microbiota. Although the impacts of water deficit (drought) on soil microbiota have been reasonably studied, microbial responses to P addition combined with soil water deficit have rarely been reported, especially in relation to the identity of aboveground tree species. This study was conducted to evaluate the main and interactive effects of drought and P addition on the soil protozoa, microbial communities as determined by phospholipids fatty acids (PLFAs) and enzyme activities in a soil vegetated with N2‐fixing or non‐N‐fixing tree species and in a non‐vegetated soil. The results indicated that the effects of drought, P addition, and their interaction on soil microbiota and chemical properties varied depending on the type of aboveground tree species. Drought significantly decreased the abundance of ciliates, amoebae, total protozoa, and most of the microbial community compared to the optimum water treatment, but the effect was more pronounced under non‐N‐fixers compared to N2‐fixers. P addition significantly increased the nitrate nitrogen (NO3−‐N) and dissolve organic nitrogen (DON) in drought treated soil as compared to the well‐watered counterpart, irrespective of the planting systems. The interaction of P with drought significantly increased the mean abundance of ciliates, flagellates, amoebae, and the total protozoa in soil vegetated with non‐N‐fixers and actinomycetes PLFAs, G+ bacterial PLFAs, and total bacterial PLFAs in the soil vegetated with N2‐fixers. Our finding points to an essential role of P addition and N2‐fixing trees on soil microbiota under drought stress. This study suggests that the effects of P application depend on its interaction with drought and that drought had decreasing effects on the abundance of ciliates, flagellates, amoebae, total protozoa, and the soil microbial communities, but the extent of it effects varied with tree species.

Benthic ciliate diversity and community composition along water depth gradients: a comparison between the intertidal and offshore areas

The diversity of marine benthic ciliates is largely known from the intertidal zone. No comparative data are available for the change of ciliate communities from the intertidal to offshore sediments in the Yellow Sea. We investigated the community composition and diversity of benthic ciliates at two intertidal (sandy and silty-sand) stations and eight offshore stations along a latitudinal transect in the Yellow Sea. The ciliate abundance and biomass decreased almost linearly with increasing water depth and distance from the intertidal zone. Diversity indices showed a similar trend. By contrast, the total species richness and taxonomic diversity were much higher in the offshore sediments than in the intertidal area. Among the total of 94 species identified, only 20 species were shared by the two habitats, which were characterized by different dominant ciliate assemblages. Carnivorous ciliates always constituted the primary feeding type in terms of biomass at all offshore stations and the intertidal sandy station, whereas at the intertidal silty-sand station the primary feeding group varied throughout the period of sampling. Multivariate analyses indicates the ciliate communities were significantly different between the two habitats. Bottom water temperature and sediment grain size were the key factors that explained the ciliate community structure.

High food availability linked to dominance of small zooplankton in a subtropical floodplain

Zooplankton body size is fundamentally affecting productivity, ecosystem respiration, nutrient cycling, and energy transfer and may be controlled by food availability but also water physical and chemical characteristics. However, the differences in control of water physical and chemical characteristics and food availability on zooplankton body size have rarely been investigated in subtropical systems. We tested the hypotheses that: (i) the type of environment, food availability, and water physical and chemical characteristics would influence body size distribution in the Upper Paraná River floodplain and nearby subsystems and (ii) in environments with higher food availability, small‐sized organisms would predominate showing higher abundance, whereas the opposite would occur in environments with lower food availability. To test these hypotheses, we performed partial redundancy and redundancy analyses (RDA). Our results showed that food availability, Secchi depth, and suspended inorganic matter influenced the body size structure of rotifers and cladocerans. Additionally, we observed that greater food availability was related to greater abundance of organisms, which were dominated by small‐sized zooplankton (size classes C2 and C1 in rotifers, and class C2′ in cladocerans). It was possible to associate different zooplankton body size spectra with phytoplankton biovolume and planktonic ciliate abundance. We suggest that large‐bodied cladocerans could have a competitive advantage over rotifers and small‐sized cladocerans when resources are scarce, because the large‐sized group could explore a wider range of resource types.

Annual variation of species richness and lorica oral diameter characteristics of tintinnids in a semi-enclosed bay of western Pacific

Much has been written on annual variation of tintinnid assemblages although the mechanism causing the annual variation has been poorly studied either in form of species richness or Lorica Oral Diameter (LOD) size-classes. In the present study, a 10-year (May 2003 to December 2012) survey on species occurrence, abundance, and LOD variation of the tintinnid ciliates was conducted in Jiaozhou Bay, western Pacific. In contrast to previous studies, we found summer peaks in tintinnid species richness in Jiaozhou Bay validated by multi-year investigations. We studied phenology of every tintinnid species and explored the mechanism causing the annual variation. The hypothesis was that tintinnid species richness has a winter baseline, to which warm water species added with the progress of the season. We defined the occurrence types of each species, and found there was only one cold occurrence type species. There was no overlap of cold occurrence type and warm occurrence type in the transitional period between winter and summer. The second aim of this study was to explore annual variations in tintinnid assemblages in form of LOD and redundant species. The species frequency distribution patterns among LOD size-classes were similar all year round. The abundance frequency distribution pattern in LOD size-classes could be divided into two phases: cold phase and warm phase with exception of May and September. The portion of redundant species was about 50% in every month. Our result help understand and predict annual variation of tintinnid assemblages in terms of species richness and LOD in world oceans.

Differences in planktonic ciliate spatial distribution in spring and autumn in the southern Yellow Sea

Seasonal variation of marine plankton spatial distribution is important in understanding the biological processes in the ocean. In this study, we studied spatial distribution of planktonic ciliate abundance and biomass in the central deep area (station depth greater than 60 m) and the coastal shallow area (station depth less than 60 m) of the southern Yellow Sea (32°–36.5°N, 121°–125°E) in spring (April) and autumn (October–November) of 2006. Our results showed that both ciliate abundance and biomass in the surface waters were higher in spring ((1 490±2 336) ind./L; (4.11±7.81) μg/L) than in autumn ((972±823) ind./L; (1.11±1.18) μg/L, calculated by carbon). Ciliate abundance and biomass in the surface waters of the coastal shallow area were similar in spring and autumn. However, in the central deep area, those values were much higher in spring ((1 878±2 893) ind./L; (5.99±10.10) μg/L) than in autumn ((738±373) ind./L; (0.74±0.76) μg/L). High values of ciliate abundance and biomass occurred in the central deep area in spring and in the coastal shallow area in autumn. Mixotrophic ciliate Laboea strobila was abundant in the central deep area in spring, when a phytoplankton bloom occurred. However, in autumn, L. strobila was abundant in the coastal shallow area. Boreal tintinnid Ptychocyli obtusa was found in spring. Both L. strobila and P. obtusa were concentrated in the surface waters when their abundance was more than 1 000 ind./L. Peaks of these species were in the subsurface waters when their abundance was less than 400 ind./L. This study showed that both high abundance and biomass of ciliates occurred in different areas in southern Yellow Sea seasonally.

Loricate ciliates as an indicator of eutrophication status in the estuarine and coastal waters

Owing to the environmental sensitivity of ciliate species, the monitoring and assessment of these communities can indicate the health of the aquatic environment. Sampling for loricate ciliates was carried out during different seasons at three different locations in the estuarine and coastal waters of Kochi, Southwest coast of India. The loricate ciliate community comprising of 27 species belonging to 10 genera revealed significant differences among the three sampling locations. The maximum numerical abundance and less species diversity of loricate ciliates were recorded at the estuarine locations whereas the minimum abundance and more species diversity were encountered in the coastal waters. Multivariate statistical analyses revealed that Tintinnopsis beroidea and Tintinnopsis uruguayensis were correlated positively with nutrients in the estuarine environment, which receives large amount of anthropogenic inputs. Thus, we propose that these two loricate ciliates may be considered as a potential bioindicator of eutrophication status in marine ecosystems.

Diversity and Distribution of Free-living Ciliates from High-Arctic Kara Sea Sediments

For the first time, free-living ciliates were studied in sediments from a variety of habitats in the Kara Sea (the Arctic Ocean). Ciliates were found in a wide range of environmental conditions (from the intertidal zone up to depths of 554m, from salinities ranging from 0 to 34psu, and from coarse sands and gravel to muddy sediments), with total abundances varying from 1 to 127ind/cm3. Altogether, 114 species were identified, most of which were widely distributed and were previously reported from other Arctic regions. An unsaturated species accumulation curve and the presence of many rare species indicated that the Kara Sea is potentially as rich in ciliates as other regions. Fine- and medium-grained sands exhibited the richest and most abundant ciliate fauna, with many interstitial forms occurring up to depths of 200m; whereas both the coarse sands of the exposed intertidal beaches and the sublittoral muds were poorly inhabited by non-specific euryoecious species. The granulometric composition of sediments was suggested to be the main driver controlling the diversity and composition of ciliate communities, while the other factors, such as salinity, water productivity and depth, were of secondary importance.

Consortial brown tide − picocyanobacteria blooms in Guantánamo Bay, Cuba

A brown tide bloom of Aureoumbra lagunensis developed in Guantánamo Bay, Cuba during a period of drought in 2013 that followed heavy winds and rainfall from Hurricane Sandy in late October 2012. Based on satellite images and water turbidity measurements, the bloom appeared to initiate in January 2013. The causative species (A. lagunensis) was confirmed by microscopic observation, and pigment and genetic analyses of bloom samples collected on May 28 of that year. During that time, A. lagunensis reached concentrations of 900,000 cells ml−1 (28 ppm by biovolume) in the middle portion of the Bay. Samples could not be collected from the northern (Cuban) half of the Bay because of political considerations. Subsequent sampling of the southern half of the Bay in November 2013, April 2014, and October 2014 showed persistent lower concentrations of A. lagunensis, with dominance shifting to the cyanobacterium Synechococcus (up to 33 ppm in April), an algal group that comprised a minor bloom component on May 28. Thus, unlike the brown tide bloom in Laguna Madre, which lasted 8 years, the bloom in Guantánamo Bay was short-lived, much like recent blooms in the Indian River, Florida. Although hypersaline conditions have been linked to brown tide development in the lagoons of Texas and Florida, observed euhaline conditions in Guantánamo Bay (salinity 35–36) indicate that strong hypersalinity is not a requirement for A. lagunensis bloom formation. Microzooplankton biomass dominated by ciliates was high during the observed peak of the brown tide, and ciliate abundance was high compared to other systems not impacted by brown tide. Preferential grazing by zooplankton on non-brown tide species, as shown in A. lagunensis blooms in Texas and Florida, may have been a factor in the development of the Cuban brown tide bloom. However, subsequent selection of microzooplankton capable of utilizing A. lagunensis as a primary food source may have contributed to the short-lived duration of the brown tide bloom in Guantánamo Bay.

景观水体周丛生纤毛虫群落结构及其与环境因子的关系

PDF HTML阅读 XML下载 导出引用 引用提醒 景观水体周丛生纤毛虫群落结构及其与环境因子的关系 DOI: 10.5846/stxb201709281752 作者: 作者单位: 水产科学国家级实验教学示范中心(上海海洋大学),水产科学国家级实验教学示范中心(上海海洋大学),水产科学国家级实验教学示范中心(上海海洋大学),水产科学国家级实验教学示范中心(上海海洋大学) 作者简介: 通讯作者: 中图分类号: 基金项目: 国家自然科学基金项目（31772477） Community structure of periphytic ciliates in scenic water and its relationship with environmental factors Author: Affiliation: National Demonstration Center for Experimental Fisheries Science Education(Shanghai Ocean University),National Demonstration Center for Experimental Fisheries Science Education (Shanghai Ocean University),National Demonstration Center for Experimental Fisheries Science Education (Shanghai Ocean University),National Demonstration Center for Experimental Fisheries Science Education (Shanghai Ocean University) Fund Project: The Natural Science Foundation of China（31772477） 摘要 | 图/表 | 访问统计 | 参考文献 | 相似文献 | 引证文献 | 资源附件 | 文章评论 摘要:为了解载玻片法获取的周丛生纤毛虫群落可否用于监测景观水体，于2015年利用载玻片采样法对上海东南角的一处景观水体的周丛生纤毛虫的群落结构进行了周年调查，并对其与环境因子之间的相关性进行了研究。共检出12目51种周丛生纤毛虫。周丛生纤毛虫的年平均密度为127.29个/cm2，2月密度最低，为24.27个/cm2，5月密度最高，为248.57个/cm2；其群落结构应对水体环境的变化呈现显著的季节性变动。多元统计分析表明，总磷浓度和水温（T）均是影响周丛生纤毛虫群落结构的主要环境因子。作为周丛生纤毛虫最主要的类群，缘毛目纤毛虫的密度与透明度（SD）和电导率（Spc）呈显著正相关，与T呈极显著正相关；丁丁目、毛口目和侧口目纤毛虫的密度与SD呈显著负相关，其中丁丁目纤毛虫的密度与T呈极显著负相关；此外，丁丁目纤毛虫的密度与总氮（TN）浓度呈极显著正相关。冗余分析显示，优势种钟形钟虫、钟虫sp.2、聚缩虫sp.1、亨氏累枝虫、沟钟虫和螅状独缩虫的密度与环境因子具有较好相关性。研究表明，载玻片法采集的周丛生纤毛虫能很好的反映水质变化，该方法可以作为景观水体水质监测方法的一个补充。 Abstract:The applicability of periphytic ciliate communities in assessing scenic water quality was studied using glass slides as artificial substrata during a 1-year cycle (January-December, 2015) for scenic water in the southeast region of Shanghai. Samples were collected monthly at a depth of 1 m, and environmental variables, namely permanganate index (CODMn), levels of chlorophyll a (Chl-a), nitrite nitrogen, total nitrogen (TN), and total phosphorus (TP), transparency (SD), water temperature (T), dissolved oxygen (DO), conductivity (Spc), salinity (Sal), and pH, were measured synchronously for comparison with biotic parameters. Totally 51 ciliate species were identified, belonging to 12 orders. The species number followed a regular pattern:spring > winter > summer > autumn; the highest species number was 27 in January, while the lowest was 10 in February. The average annual abundance of periphytic ciliates was 127.29 individuals per square centimeter; the lowest abundance was 24.27 individuals per square centimeter in February, while the highest was 248.57 individuals per square centimeter in May. Multivariate analysis suggested that TP and T were major environmental factors influencing the community structure of periphytic ciliates, and the combination of TP, T, DO, and pH could best explain the changes in the community structure of periphytic ciliates. Pearson's correlation analysis indicated that the average monthly abundance of periphytic ciliates had significant positive correlations with T and Spc. Peritrichida had significant positive correlations with SD and Spc, and highly significant positive correlation with T; Tintinnida correlated significantly with T, TN, and SD; whereas, Pleurostomatida had a significant negative correlation with SD. The dominant species correlated significantly with environmental variables, as well. Vorticella campanula, Vorticella sp. 2, Zoothamnium sp. 1, and Epistylis hentscheli had positive correlations with SD and T, and negative correlations with DO, TN, and Sal; Vorticella convallaria correlated significantly with SD, TN, TP, CODMn, and Sal; Carchesium polypinum correlated negatively with T and SD, and positively with DO, TN, and Sal. In conclusion, periphytic ciliates are good bioindicators for evaluating the quality of water bodies, and the glass slide method can be used as a supplementary approach to the monitoring of scenic water quality. 参考文献 相似文献 引证文献

Large‐scale patterns of biofilm‐dwelling ciliate communities in a river network: Only small effects of stream order

Although biofilm‐dwelling microfauna (i.e., small metazoans and protzoans) can play an important role in the flux of matter in running waters, their dynamics, and control within stream networks are as yet poorly understood. Here, we analyzed the longitudinal (from first order stream to large river) dynamics of ciliates associated to hard substrate within a river network. Both ciliate abundance and their taxonomical community structure showed no correlations to stream order, although the community structure of the largest river, the Rhine, differed from those of the other rivers. The abundances of biofilm‐dwelling bacteria, algae, rotifers, and nematodes also showed no correlation with stream order. The above results contrast to the abundances of planktonic algae and bacteria that were significantly and positively correlated with the stream order. The results showed that stream size and the corresponding planktonic resource concentration are not reliable parameters in predicting the abundances and community structures of biofilm‐dwelling ciliates. In fact, local parameters seemed to have stronger effects on benthic microfauna communities. Thus, the impact of small‐scale habitat patterns needs further attention in explaining the community structure of biofilm‐dwelling ciliates.

Effect of Dietary Forage to Concentrate Ratios on Dynamic Profile Changes and Interactions of Ruminal Microbiota and Metabolites in Holstein Heifers.

A better understanding of global ruminal microbiota and metabolites under extensive feeding conditions is a prerequisite for optimizing rumen function and improving ruminant feed efficiency. Furthermore, the gap between the information on the ruminal microbiota and metabolites needs to be bridged. The aim of this study was to investigate the effects of a wide range of forage to concentrate ratios (F:C) on changes and interactions of ruminal microbiota and metabolites. Four diets with different F:C (80:20, 60:40, 40:60, and 20:80) were limit-fed to 24 Holstein heifers, and Illumina MiSeq sequencing and gas chromatography time-of-flight/mass spectrometry were used to investigate the profile changes of the ruminal microbes and metabolites, and the interaction between them. The predominant bacterial phyla in the rumen were Bacteroidetes (57.2 ± 2.6%) and Firmicutes (26.8 ± 1.6%), and the predominant anaerobic fungi were Neocallimastigomycota (64.3 ± 3.8%) and Ascomycota (22.6 ± 2.4%). In total, 44, 9, 25, and 2 genera, respectively, were identified as the core rumen bacteria, ciliate protozoa, anaerobic fungi, and archaea communities across all samples. An increased concentrate level linearly decreased the relative abundance of cellulolytic bacteria and ciliates, namely Fibrobacter, Succinimonas, Polyplastron, and Ostracodinium (q < 0.05), and linearly increased the relative abundance of Entodinium (q = 0.04), which is a non-fibrous carbohydrate degrader. Dietary F:C had no effect on the communities of anaerobic fungi and archaea. Rumen metabolomics analysis revealed that ruminal amino acids, lipids, organic acids, and carbohydrates were altered significantly by altering the dietary F:C. With increasing dietary concentrate levels, the proportions of propionate and butyrate linearly increased in the rumen (P ≤ 0.01). Correlation analysis revealed that there was some utilization relationship or productive association between candidate metabolites and affected microbe groups. This study provides a better understanding of ruminal microbiota and metabolites under a wide range of dietary F:C, which could further reveal integrative information of rumen function and lead to an improvement in ruminant production.

Ciliates as restoration indicators in peatbogs — 10 years of study

There is almost no information on how restoration of Sphagnum-dominated peatbogs, and in particular removal of reeds, affects the functioning of ciliate communities. Changes in vegetation patterns caused by restoration procedures may take years to be observed, while microbial processes already display effects after short-term exposure to changes in environmental conditions due to restoration. Based on the results of a long-term study, we assumed that mowing down of reeds causes changes in the physicochemical properties of peatbog water and sought to answer the question of how ciliate communities react to these changes and whether these microorganisms can play a significant role as bioindicators in evaluating the restoration process. Removal of reeds clearly modified the taxonomic composition and abundance of ciliates. This was reflected in an increase in the abundance and diversity of these protozoa and in a significant increase in the proportion of sphagnophilous species. Our results suggest an indicator species approach based on functional groups may be appropriate for biomonitoring peatbog restoration. A better understanding of what regulates microbial populations and activity in peatbogs and unravelling of these fundamental mechanisms are particularly critical in order to more accurately predict how peatbogs will respond to anthropogenic disturbances.

P.5.b.010 - Comparative study of the effects of supportive educational programs: for family caregivers of the elderly with dementia

Owing to the environmental sensitivity of ciliate species, the monitoring and assessment of these communities can indicate the health of the aquatic environment. Sampling for loricate ciliates was carried out during different seasons at three different locations in the estuarine and coastal waters of Kochi, Southwest coast of India. The loricate ciliate community comprising of 27 species belonging to 10 genera revealed significant differences among the three sampling locations. The maximum numerical abundance and less species diversity of loricate ciliates were recorded at the estuarine locations whereas the minimum abundance and more species diversity were encountered in the coastal waters. Multivariate statistical analyses revealed that Tintinnopsis beroidea and Tintinnopsis uruguayensis were correlated positively with nutrients in the estuarine environment, which receives large amount of anthropogenic inputs. Thus, we propose that these two loricate ciliates may be considered as a potential bioindicator of eutrophication status in marine ecosystems.

The Response of Heterotrophic Prokaryote and Viral Communities to Labile Organic Carbon Inputs Is Controlled by the Predator Food Chain Structure.

Factors controlling the community composition of marine heterotrophic prokaryotes include organic-C, mineral nutrients, predation, and viral lysis. Two mesocosm experiments, performed at an Arctic location and bottom-up manipulated with organic-C, had very different results in community composition for both prokaryotes and viruses. Previously, we showed how a simple mathematical model could reproduce food web level dynamics observed in these mesocosms, demonstrating strong top-down control through the predator chain from copepods via ciliates and heterotrophic nanoflagellates. Here, we use a steady-state analysis to connect ciliate biomass to bacterial carbon demand. This gives a coupling of top-down and bottom-up factors whereby low initial densities of ciliates are associated with mineral nutrient-limited heterotrophic prokaryotes that do not respond to external supply of labile organic-C. In contrast, high initial densities of ciliates give carbon-limited growth and high responsiveness to organic-C. The differences observed in ciliate abundance, and in prokaryote abundance and community composition in the two experiments were in accordance with these predictions. Responsiveness in the viral community followed a pattern similar to that of prokaryotes. Our study provides a unique link between the structure of the predator chain in the microbial food web and viral abundance and diversity.

Using in situ flow cytometry images of ciliates and dinoflagellates for aquatic system monitoring.

Short-period variability in plankton communities is poorly documented, especially for variations occurring in specific groups in the assemblage because traditional analysis is laborious and time-consuming. Moreover, it does not allow the high sampling frequency required for decision making. To overcome this limitation, we tested the submersible CytoSub flow cytometer. This device was anchored at a distance of approximately 10 metres from the low tide line at a depth of 1.5 metres for 12 hours to monitor the plankton at a site in the biological reserve of Barra da Tijuca beach, Rio de Janeiro. Data analysis was performed with two-dimensional scatter plots, individual pulse shapes and micro images acquisition. High-frequency monitoring results of two interesting groups are shown. The abundance and carbon biomass of ciliates were relatively stable, whereas those from dinoflagellates were highly variable along the day. The linear regression of biovolume measures between classical microscopy and in situ flow cytometry demonstrate high degree of adjustment. Despite the success of the trial and the promising results obtained, the large volume of images generated by the method also creates a need to develop pattern recognition models for automatic classification of in situ cytometric images.

Rapid turnover of ciliate community members in New England tide pools

AME Aquatic Microbial Ecology Contact the journal Facebook Twitter RSS Mailing List Subscribe to our mailing list via Mailchimp HomeLatest VolumeAbout the JournalEditorsSpecials AME 80:43-54 (2017) - DOI: https://doi.org/10.3354/ame01839 Rapid turnover of ciliate community members in New England tide pools Mary Badger1, Sarah J. Tucker1,3, Jean-David Grattepanche1, Laura A. Katz1,2,* 1Department of Biological Sciences, Smith College, Northampton, Massachusetts 01063, USA 2Program in Organismic and Evolutionary Biology, University of Massachusetts, Amherst, Massachusetts 01003, USA 3Present address: Hawaii Institute of Marine Biology, Department of Marine Biology, University of Hawaii, Kaneohe, Hawaii 96744, USA *Corresponding author: lkatz@smith.edu ABSTRACT: The rocky intertidal zone represents a dynamic habitat marked by considerable species richness, which has been well-documented for invertebrates and macroalgae. This high biodiversity exists in the context of extreme fluctuations in abiotic factors such as temperature, salinity and pH that occur during each tidal cycle. Despite these attributes, few studies have focused on microbial diversity in tide pools, including analyses of the ciliate communities that are the focus of this study. We investigated the spatial and temporal distributions of ciliate species across the intertidal environment at sites in Maine and Connecticut, USA. Our study used a DNA fingerprinting technique, denaturing gradient gel electrophoresis (DGGE), which allows for genetic analyses of abundant community members. We investigated how ciliate diversity changed across several spatiotemporal scales: (1) between the open ocean and tide pools, (2) among different tide pools at varying distances from the low tide mark and (3) at differing times within a tidal cycle. In addition, we examined the differences between active and non-active members in these extreme environments by investigating diversity of both ribosomal DNA and RNA. In both Maine and Connecticut, we found abundant ciliate taxa that are either rare or absent in the open ocean, and that appear to quickly dominate tide pools once they are isolated from the open ocean. We also found that ciliate distributions within the tide pool community are complex and variable across spatial and temporal scales. KEY WORDS: Microbial diversity · Ephemeral habitats · Biogeography · Denaturing gradient gel electrophoresis · Extreme environments Full text in pdf format Supplementary material PreviousNextCite this article as: Badger M, Tucker SJ, Grattepanche JD, Katz LA (2017) Rapid turnover of ciliate community members in New England tide pools. Aquat Microb Ecol 80:43-54. https://doi.org/10.3354/ame01839 Export citation RSS - Facebook - Tweet - linkedIn Cited by Published in AME Vol. 80, No. 1. Online publication date: August 11, 2017 Print ISSN: 0948-3055; Online ISSN: 1616-1564 Copyright © 2017 Inter-Research.