Ecology Of Plankton Research Articles

Environmental predictors of electroactive bacterioplankton in small boreal lakes.

Extracellular electron transfer (EET) by electroactive bacteria in anoxic soils and sediments is an intensively researched subject, but EET's function in planktonic ecology has been less considered. Following the discovery of an unexpectedly high prevalence of EET genes in a bog lake's bacterioplankton, we hypothesized that the redox capacities of dissolved organic matter (DOM) enrich for electroactive bacteria by mediating redox chemistry. We developed the bioinformatics pipeline FEET (Find EET) to identify and summarize predicted EET protein-encoding genes from metagenomics data. We then applied FEET to 36 bog and thermokarst lakes and correlated gene occurrence with environmental data to test our predictions. Our results provide indirect evidence that DOM may participate in bacterioplankton EET. We found a similarly high prevalence of genes encoding putative EET proteins in most of these lakes, where oxidative EET strongly correlated with DOM. Numerous novel clusters of multiheme cytochromes that may enable EET were identified. Taxa previously not considered EET-capable were found to carry EET genes. We propose that EET and DOM interactions are of ecologically important to bacterioplankton in small boreal lakes, and that EET, particularly by methylotrophs and anoxygenic phototrophs, should be further studied and incorporated into methane emission models of melting permafrost.

Investigation of the ecology of winter plankton of Lake Baikal using complex instrumental methods

Aim . The continuous monitoring of changes in ecosystems must be carried out in connection with global climate changes that affect the state of water bodies. Remote sensing methods have many advantages as a promising method for monitoring biocenoses in large water bodies. We carried out a comprehensive study comparing the results obtained using the latest instruments and methods to expand their further application to the continuous monitoring of water bodies. Material and Methods . The field research was undertaken using hydroacoustic sensors, submersible holographic camera and high‐resolution thermal sensors in addition to the classical methods of studying the zooplankton ecology – the Juday net and CTD probe. Water temperature, chlorophyll, photosynthetically active radiation and other parameters were measured with an AAQ‐Rinko probe. We provided data for one vertical up to a depth of 100 m. Results . The main components of mesozooplankton during the ice period are different age stages of the endemic crustacean Epischura baikalensis Sars 1900 and several rotifer species. The article discusses the heterogeneity of the environment and the distribution of plankton detected by various instruments. Conclusion . The experimental results obtained with the help of a set of devices show that the distribution of zooplankton is very strongly dependent on the physical parameters of the environment. The use of remote sensing methods is an important step towards the automation of basic monitoring of the ecosystem of Lake Baikal and other water bodies. The obtained field data will make it possible to further improve the pattern recognition algorithm in the software of the holographic installation for the specific conditions of Lake Baikal. The results of the vertical distribution and migrations of zooplankton in connection with environmental parameters are assumed to be processed using mathematical modeling methods.

The Seasonal Microbial Ecology of Plankton and Plankton-Associated Vibrio parahaemolyticus in the Northeast United States.

ABSTRACTMicrobial ecology studies have proven to be important resources for improving infectious disease response and outbreak prevention. Vibrio parahaemolyticus is an ongoing source of shellfish-borne food illness in the Northeast United States, and there is keen interest in understanding the environmental conditions that coincide with V. parahaemolyticus disease risk, in order to aid harvest management and prevent further illness. Zooplankton and chitinous phytoplankton are associated with V. parahaemolyticus dynamics elsewhere; however, this relationship is undetermined for the Great Bay estuary (GBE), an important emerging shellfish growing region in the Northeast United States. A comprehensive evaluation of the microbial ecology of V. parahaemolyticus associated with plankton was conducted in the GBE using 3 years of data regarding plankton community, nutrient concentration, water quality, and V. parahaemolyticus concentration in plankton. The concentrations of V. parahaemolyticus associated with plankton were highly seasonal, and the highest concentrations of V. parahaemolyticus cultured from zooplankton occurred approximately 1 month before the highest concentrations of V. parahaemolyticus from phytoplankton. The two V. parahaemolyticus peaks corresponded with different water quality variables and a few highly seasonal plankton taxa. Importantly, V. parahaemolyticus concentrations and plankton community dynamics were poorly associated with nutrient concentrations and chlorophyll a, commonly applied proxy variables for assessing ecological health risks and human health risks from harmful plankton and V. parahaemolyticus elsewhere. Together, these statistical associations (or lack thereof) provide valuable insights to characterize the plankton-V. parahaemolyticus dynamic and inform approaches for understanding the potential contribution of plankton to human health risks from V. parahaemolyticus for the Northeast United States.IMPORTANCE The Vibrio-plankton interaction is a focal relationship in Vibrio disease research; however, little is known about this dynamic in the Northeast United States, where V. parahaemolyticus is an established public health issue. We integrated phototactic plankton separation with seasonality analysis to determine the dynamics of the plankton community, water quality, and V. parahaemolyticus concentrations. Distinct bimodal peaks in the seasonal timing of V. parahaemolyticus abundance from phyto- versus zooplankton and differing associations with water quality variables and plankton taxa indicate that monitoring and forecasting approaches should consider the source of exposure when designing predictive methods for V. parahaemolyticus. Helicotheca tamensis has not been previously reported in the GBE. Its detection during this study provides evidence of the changes occurring in the ecology of regional estuaries and potential mechanisms for changes in V. parahaemolyticus populations. The Vibrio monitoring approaches can be translated to aid other areas facing similar public health challenges.

Phytoplankton Studies of the Rabigh Dam Stream, Makkah Province, Saudi Arabia

A PRELIMINARY Checklist on phytoplankton dynamics of the Rabigh Dam Stream was investigated during the wet (January and February) and arid (July and August) seasons of 2018. Composite sample were collected along the Rabigh Dam Stream. These outcomes provide useful information on the checklists and ecology of plankton’s species which could be potentially used as bio-indicators for assessing and monitoring the Rabigh Dam Stream. Five main algal groups were recorded namely: Cyanophyceae, Chlorophyceae, Euglenophyceae, Bacillariophyceae and Pyrrophyceae. This study identified 65 phytoplankton species consisted of Blue-green algae (9 species), Green algae (46 species), Euglenoids (1 species), Diatoms (6 species), and Dinoflagellates (3 species). The following order of dominance was; Cyanophyceae> Chlorophyceae> Euglenophyceae> Bacillariophyceae> Dinophyceae. In spite the number of blue-green algal species was low, they represented 63.62% of the total phytoplankton followed by Chlorophyceae (19.08%), Euglenophyceae (11.21%), Bacillariophyceae (5.72%), respectively. On the other hand, the Dinophyceae represented the rarely group (0.37%) of the total phytoplankton. There were main changes in phytoplankton composition due to the projects drinking water reservoir construction. It could be related to the severe human activities and difference in sampling strategies. It was concluded that all the dams had well balanced phytoplankton communities. The changes in phytoplankton composition and numbers were significantly varying among the period of study.

Ecology and Diversity of Plankton in Kotmale Reservoir, Sri Lanka

Present study investigated the relationship between plankton communities and environmental variables in five different locations of the Kotmale Reservoir during the period of June 2008 to May 2011. A total of 123 plankton species were recorded with 85 species of phytoplankton and 38 species of zooplankton. The relative abundance data indicate that Aulacoseira granulata (31.06%), Botryococcus braunii (12.34%) and Microcystis sp. (11.93%) were the dominant phytoplankton species while Acanthocystis turfacea (52.22%) was the dominant zooplankton species. Staurastrum cingulum was the dominant species in sites where the immediate catchment is covered with reservation forest with no significant inflow streams. Aulacoseira granulata, Fragellaria capucina and Navicula sp. were abundant in locations where the highest total phosphorus (TP) values were recorded. The main inflow streams, Puna Oya and Pundalu Oya appear to bring nutrient rich waters from its catchment with dense tea estates, agricultural lands, industries and villages. Microcystis sp. was abundant in locations where the highest values for TP, dissolved phosphorus (DP), ammonia, conductivity and turbidity were recorded. Botryococcus braunii was dominant in the location where Puna Oya reaches the reservoir. Staurastrumlepta canthum was abundant in the location located closer to the dam where the water body mostly contains limnetic characteristics. Among the zooplankton, cladocera species were abundant in sites where Staurastrum cingulum was identified. Rotifers and ciliate protozoans were identified closer to the dam and at the sites with high dominance of Microcystis sp. Accordingly, it was apparent that the distribution and abundance of these plankton species depend on the prevailing environmental conditions which ultimately show their ability to use as environmental indicators.

プランクトンの分類・生態研究，その現状と最新知見

プランクトンの分類・生態研究，その現状と最新知見

Chemical ecology of the marine plankton.

Covering: January 2015 through December 2017 This review focuses on recent studies on the chemical ecology of planktonic marine ecosystems, with the objective of presenting a comprehensive overview of new findings in the field in the time period covered. In order to highlight the role of chemically mediated interactions in the marine plankton this review has been organized by ecological concepts starting with intraspecific communication, followed by interspecific interactions (including facilitation and mutualism, host-parasite, allelopathy, and predator-prey), and finally the effects of plankton secondary metabolites on community and ecosystem-wide interactions.

Exploring spatio-temporal patterns of plankton diversity and community structure as correlates of water quality in a tropical stream

Ecology of plankton in the downstream reaches of Kaduna River, Zungeru, Niger state, Nigeria was investigated between April and August 2015. Plankton and surface water samples were collected monthly from three stations for analysis of plankton diversity and physico-chemical parameters respectively. Station 1 is relatively unperturbed station located at the outskirts of Zungeru town, station 2 with moderate human activity located in Zungeru town while station 3 with minimal level of anthropogenic activities was located in Wushishi town about 7km from station 2. The result revealed that the minimum and maximum values for pH water temperature, air temperature, conductivity, dissolved oxygen (DO) biochemical oxygen demand (BOD), phosphate, Nitrate, and secchi disc transparency were 5.38–6.79, 25–31°C, 26–31°C, 32–72μs/cm, 3.50–8.20mg/l, 1.00–5.00mg/l, 0.06–1.13mg/l 0.44–1.31mg/l, 39.140cm respectively. A total of 26 species of zooplankton and 24 species of phytoplankton were encountered in the study. The highest number of plankton (20 taxa) was recorded at station 2 while station 1 with 18 taxa and station 3 with 13 representative taxa. For zooplankton, the highest number of taxa was recorded at station 1 (20 taxa), followed by station 3 (14 taxa) and 10 taxa in station 2 were identified. Copepoda of the order cyclopidae dominated all the three stations while Bacillariophyta dominated the three stations for phytoplankton diversity. Canonical correspondence analysis (CCA) ordination was used to determine phytoplankton and zooplankton abundance in relation to the physico-chemical parameters. Nitrate, phosphate and dissolved oxygen had over riding influence on the distribution of the plankton in the water body which indicate that the river is still very productive in terms of providing starter food organisms for higher aquatic life. However, care should be taken to protect the river from further deterioration due to various degrees of human activities.

Claudia Castellani and Martin Edwards [eds.]. 2017. Marine Plankton: A Practical Guide to Ecology, Methodology, and Taxonomy. Oxford University Press, Oxford, ISBN 978-0-19-923326-7, DOI:10.1093/acprof:oso/9780199233267.001.0001, 704 p, Suggested retail p

Claudia Castellani and Martin Edwards [eds.]. 2017. Marine Plankton: A Practical Guide to Ecology, Methodology, and Taxonomy. Oxford University Press, Oxford, ISBN 978-0-19-923326-7, DOI:10.1093/acprof:oso/9780199233267.001.0001, 704 p, Suggested retail p

Metamorphosis Is Ancestral for Crown Euarthropods, and Evolved in the Cambrian or Earlier.

Macroevolutionary developmental biology employs fossilized ontogenetic data and phylogenetic comparative methods to probe the evolution of development at ancient nodes. Despite the prevalence of ecologically differentiated larval forms in marine invertebrates, it has been frequently presumed that the ancestors of arthropods were direct developers, and that metamorphosis may not have evolved until the Ordovician or later. Using fossils and new dated phylogenies, I infer that metamorphosis was likely ancestral for crown arthropods, contradicting this assumption. Based on a published morphological dataset encompassing 217 exceptionally preserved fossil and 96 extant taxa, fossils were directly incorporated into both the topology and age estimates, as in "tip dating" analyses. Using data from post-embryonic fossils representing 25 species throughout stem and crown arthropod lineages (as well as most of the 96 extant taxa), characters for metamorphosis were assigned based on inferred ecological changes in development (e.g., changes in habitat and adaptive landscape). Under all phylogenetic hypotheses, metamorphosis was supported as most likely ancestral to both ecdysozoans and euarthropods. Care must be taken to account for potential drastic post-embryonic morphological changes in evolutionary analyses. Many stem group euarthrpods may have had ecologically differentiated larval stages that did not preserve in the fossil record. Moreover, a complex life cycle and planktonic ecology may have evolved in the Ediacaran or earlier, and may have typified the pre-Cambrian explosion "wormworld" prior to the origin of crown group euarthropods.

Chemical ecology of marine plankton.

Covering: January 2013 to online publication December 2014This review summarizes recent research in the chemical ecology of marine pelagic ecosystems, and aims to provide a comprehensive overview of advances in the field in the time period covered. In order to highlight the role of chemical cues and toxins in plankton ecology this review has been organized by ecological interaction types starting with intraspecific interactions, then interspecific interactions (including facilitation and mutualism, host-parasite, allelopathy, and predator-prey), and finally community and ecosystem-wide interactions.

Effect of solar UVR on the production of particulate and dissolved organic carbon from phytoplankton assemblages in the Indian Ocean

This study shows the effects of solar UVR on the photosynthetic parameters and the production of both particulate and dissolved organic carbon (POC and DOC, respectively) of phytoplankton assemblages from oligotrophic areas of the southeastern Indian Ocean. Samples from the 20% PAR depth were incubated on deck under different intensities of 2 different light regimes: full solar radiation (PAR+UVR) and excluding UVR (PAR). Phytoplankton production was measured by the 14 C method, obtaining size-fractionated POC (0.2, 2 and 20 µm), total POC and DOC. POC values were fit to a photosynthesisirradiance (P−E) model that includes photoinhibi- tion. Phytoplankton populations under PAR+UVR had a 10% lower maximum photosynthetic rate (Ps B ) and an 86% higher sensitivity to inhibition (β) than populations incubated under only PAR exposures. For some stations, cells larger than 2 µm showed higher Ps B and photosynthetic effi- ciency (measured as the P−E slope, α) than smaller cells, but no significant differences were found for β. In contrast, DOC production was significantly higher under PAR+UVR than under PAR exposures and did not follow the P−E model used for fitting POC. The analysis of the P−E values for DOC production showed that values remained constant under PAR intensities but increased with increasing irradiance in the presence of UVR. In some cases, inhibition of DOC production at high irradiances was also observed. These results demonstrate the relevance of UVR irradiance as an environmental driver for phytoplanktonic DOC production in oligotrophic waters and reinforce the important role of UVR on the physiology and ecology of tropical plankton.

Evaluation of Blue Crab, Callinectes sapidus, Megalopal Settlement and Condition during the Deepwater Horizon Oil Spill.

The Blue Crab, Callinectes sapidus, is a commercially, culturally, and ecologically significant species in the Gulf of Mexico (GOM), whose offshore stages were likely impacted by the Deepwater Horizon oil spill (DWH). To test for DWH effects and to better understand the planktonic ecology of this species, we monitored Callinectes spp. megalopal settlement and condition at sites within and outside of the spill extent during and one year after the DWH. We tested for DWH effects by comparing 2010 settlement against baseline data available for two sites, and by testing for differences in settlement and condition inside and outside of the spill extent. We also developed time series models to better understand natural drivers of daily settlement variation (seasonal and lunar trends, hydrodynamics, wind) during 2010 and 2011. Overall, we found that neither megalopal settlement nor body weight were significantly reduced at oiled sites, but that high unexplained variation and low statistical power made detection of even large effects unlikely. Time series models revealed remarkably consistent and relatively strong seasonal and lunar trends within sites (explaining on average 28% and 9% of variation, respectively), while wind and hydrodynamic effects were weak (1–5% variation explained) and variable among sites. This study provides insights into DWH impacts as well as the natural drivers of Callinectes spp. megalopal settlement across the northern GOM.

Ecology, Virulence, and Phylogeny of Blastulidium paedophthorum, a Widespread Brood Parasite of Daphnia spp.

Parasitism is now recognized as a major factor impacting the ecology and evolution of plankton, including Daphnia. Parasites that attack the developing embryos of daphniids, known as brood parasites, were first described in the early 1900s but have received relatively little study. Here, we link previous morphological descriptions of the oomycete brood parasite Blastulidium paedophthorum with information on its phylogenetic placement, ecology, and virulence. Based on the morphology and phylogenetic relationship with other members of the Leptomitales, we show that a brood parasite observed in daphniids in the Midwestern United States is B. paedophthorum. We used morphology, DNA sequences, and laboratory infection experiments to show that B. paedophthorum is a multihost parasite that can be transmitted between species and genera. A field survey of six hosts in 15 lakes revealed that B. paedophthorum is common in all six host taxa (present on 38.3% of our host species-lake-sampling date combinations; the maximum infection prevalences were 8.7% of the population and 20% of the asexual adult female population). Although B. paedophthorum was observed in all 15 lakes, presence and infection prevalence varied among lakes. Infection with B. paedophthorum did not reduce host life span but significantly impacted host fecundity. Theory predicts that parasites that affect host fecundity without affecting host life span should have the strongest impact on host population dynamics. Based on its virulence and commonness in natural populations and on the central role of daphniids in freshwater food webs, we predict that B. paedophthorum will influence daphniid ecology and evolution, as well as the larger food web.

The Characterization of RNA Viruses in Tropical Seawater Using Targeted PCR and Metagenomics

ABSTRACTViruses have a profound influence on the ecology and evolution of plankton, but our understanding of the composition of the aquatic viral communities is still rudimentary. This is especially true of those viruses having RNA genomes. The limited data that have been published suggest that the RNA virioplankton is dominated by viruses with positive-sense, single-stranded (+ss) genomes that have features in common with those of eukaryote-infecting viruses in the order Picornavirales (picornavirads). In this study, we investigated the diversity of the RNA virus assemblages in tropical coastal seawater samples using targeted PCR and metagenomics. Amplification of RNA-dependent RNA polymerase (RdRp) genes from fractions of a buoyant density gradient suggested that the distribution of two major subclades of the marine picornavirads was largely congruent with the distribution of total virus-like RNA, a finding consistent with their proposed dominance. Analyses of the RdRp sequences in the library revealed the presence of many diverse phylotypes, most of which were related only distantly to those of cultivated viruses. Phylogenetic analysis suggests that there were hundreds of unique picornavirad-like phylotypes in one 35-liter sample that differed from one another by at least as much as the differences among currently recognized species. Assembly of the sequences in the metagenome resulted in the reconstruction of six essentially complete viral genomes that had features similar to viruses in the families Bacillarna-, Dicistro-, and Marnaviridae. Comparison of the tropical seawater metagenomes with those from other habitats suggests that +ssRNA viruses are generally the most common types of RNA viruses in aquatic environments, but biases in library preparation remain a possible explanation for this observation.

Chemical ecology of the marine plankton

Covering: October 2010 to December 2012. Previous review Nat. Prod. Rep. 2011, 28, 388–399This review summarizes recent work in the chemical ecology of pelagic marine ecosystems. In order to provide a comprehensive overview of advances in the field over the period covered, we have organized this review by ecological interaction type beginning with intraspecific interactions, then interspecific interactions (including mutualism, parasitism, competition, and predation), and finally community- and ecosystem-wide interactions.

Chemical ecology of the marine plankton

This review summarizes recent work in the chemical ecology of pelagic marine ecosystems. In order to provide a comprehensive overview of advances in the field over the period covered, we have organized this review by ecological interaction type beginning with intraspecific interactions, then interspecific interactions (including mutualism, parasitism, competition, and predation), and finally community- and ecosystem-wide interactions.

Chemical ecology of the marine plankton

Chemical ecology of the marine plankton

남해 거제도 장목만에서 부유성 섬모충의 시기별 분포 특성

Ciliate plankton samples were collected biweekly from July 2006 to June 2008 in Jangmok Bay of Geoje Island. Species composition and abundances were analyzed by quantitative protargol stain and environmental parameters were also examined. A total of 88 ciliate species occurred during the study period, consisting of 22 tintinnids, 51 oligotrichs, and 15 other species. Higher ciliate abundances appeared from June to October during the warm season (<TEX>$</TEX><TEX><</TEX><TEX>20^{\circ}C$</TEX>) and the maximum (<TEX>$4.0{\times}10^4\;cells\;L^1</TEX>$) in August, while the lower abundances were found during the cold season. The minimun ciliate abundance was found in November when water temperature rapidly decreased. The temporal succession of dominant species was very clear and opportunistic. Pelagostrombidium sp., Tontonia simplicidens, Helicostomella subulata, and Myrionecta rubra were co-dominant in summer while Rimostrombidium orientale occurred abundantly in winter. Strombidium tressum and S. compressum, eurythermal species, were observed during all seasons. Based on the species-specific ecology of ciliate plankton, it is suggested that the indicative ciliate species can be applied as a biological tool to detect environmental change in the southern coastal waters of korea.

Ecology of plankton in some paddy fields, near Nagri bus stand, Kathua (J&amp;K state)

Physico-chemical characteristics of water and plankton were analysed from four paddy fields, irrigated by a tributary of the river Ravi, near Nagri bus stand, Kathua, J&amp;K, during July, 2005 to September, 2005 have been described. Phytoplankton has shown the presence of Chlorophyceae (14 genera), Bacillariophyceae (9 genera) and Cyanophyceae (6 genera). The order of qualitative dominance of zooplankton is observed as Protozoa (10 genera and 31 species) &gt; Rotifera (8 genera and 9 species) &gt; Arthropoda (8 genera, 8 species and 3 larvae) &gt; Annelida (1 genus and I species) and&gt; Nematoda. Planktonic diversity and density remained low during first two observations (preparation of fields and seedlings transplantation). Coefficient of correlation (r) of phytoplankton and zooplankton, with the various parameters of water, is insignificant.