Zooplankton Biodiversity Research Articles

Environmental Factors Controlling Zooplankton Communities in Thermokarst Lakes of the Bolshezemelskaya Tundra Permafrost Peatlands (NE Europe)

Environmental physical and chemical factors controlling the abundance and biodiversity of zooplankton in permafrost-affected lakes are poorly known yet they determine the response of aquatic ecosystems to on-going climate change and water warming. Here, we assess the current status of zooplankton communities in lakes of the Bolshezemelskaya Tundra (permafrost peatlands of NE Europe), and provide new information about the composition and structure of zooplankton. The results demonstrate that the structure of zooplankton communities is influenced by the morphometric features of lakes and the degree of lake overgrowth by macrophytes. According to the level of quantitative development of zooplankton, most tundra lakes were of the oligotrophic type with an average wet biomass of up to 1 g/m3. The largest number of species was observed in zooplankton communities of small thaw ponds with an area of up to 0.02 km2 and overgrown with macrophytes. The analysis of factors that influence the formation of the lake zoocenosis demonstrated that the species composition and quantitative characteristics of zooplankton are chiefly controlled by pH and water mineralization. A comparison of the results obtained with the literature data on the lakes of this region collected 60 years ago suggests that the ecosystems of these lakes are in a stable state. Overall, these new insights will improve our knowledge of factors controlling the zooplankton spatial dynamics in unique but quite abundant thermokarst lakes of NE European Tundra, subjected to on-going climate warming.

Documenting the impacts of increasing salinity in freshwater and coastal ecosystems: Introduction to the special issue

Documenting the impacts of increasing salinity in freshwater and coastal ecosystems: Introduction to the special issue

Biodiversity of Zooplankton as Bio-Indicator for Water Criteria at Jazan Coastal Areas

Biodiversity of Zooplankton as Bio-Indicator for Water Criteria at Jazan Coastal Areas

Purification performance from bypass ecological treatment systems treating WWTPs effluents and improvement of water quality in receiving rivers: A case study in southern China

Effluents from wastewater treatment plants (WWTPs) is the main source of pollution in rivers in developing countries. In this case study, three bypass ecological treatment systems along urban rivers achieved high removal efficiencies for chemical oxygen demand (COD; 55.7–64.0%), ammonium N (NH4+-N; 63.1–89.4%) and total phosphorous (TP; 27.6–76.7%). 16 S rRNA gene sequencing analysis confirmed that Proteobacteria was the main bacterial phylum (44.4%) in the ecological treatment system, and members were enriched significantly in the non-aeration area (59.3%). The relative abundance of Nitrospirae was highest in the inflow area (25.0%), but restrained in the non-aeration area (5.7%). 18 S rRNA gene annotation results indicated that phylum Rotifer was gradually inhibited with the direction of water flow and diffusion, while phylum Rhodophyta displayed the opposite trend. After implementation of bypass ecological treatment systems, receiving rivers were improved significantly from Grade Ⅴ to Ⅳ, and the biodiversity of zooplankton, zoobenthos and fish communities was greatly improved.

Metabarcoding of zooplankton to derive indicators of pelagic ecosystem status

Zooplankton play a key role in marine food webs and carbon cycling and are useful indicators of climaterelated changes and ocean health in pelagic ecosystems. Zooplankton are traditionally identified to species through microscopy, but new molecular techniques have enabled the identification of individual specimens (DNA barcoding) or multiple species in the same sample (DNA metabarcoding). Metabarcoding has been tested and refined using zooplankton collected in South African waters for the first time. Challenges to the implementation of DNA-based methods to measure zooplankton biodiversity easily and routinely include an incomplete DNA barcode reference library, logistical complexity and uptake of the new technology by environmental management agencies. These challenges call for a national effort to intensify zooplankton barcoding initiatives and to effectively engage stakeholders in developing a roadmap towards application of DNA-based methods in marine environmental management. Significance: Metabarcoding has been successfully applied to marine zooplankton for the first time in South Africa, demonstrating its potential as a tool to generate ecosystem indicators during routine ocean observations. National barcoding efforts must be intensified to provide a comprehensive reference library of zooplankton DNA. Effective engagement with stakeholders is required to overcome logistical and policy challenges, and to provide a roadmap towards application of DNA-based methods in marine environmental management.

Copepod functional traits and groups show divergent biogeographies in the global ocean

AbstractAimThe distribution of zooplankton functional traits is a key factor for regulating food web dynamics and carbon cycling in the oceans. Yet, we lack a clear understanding of how many functional groups (FGs) exist in the zooplankton and how their traits are distributed on a global scale. Here, we model and map the environmental habitats of copepod (i.e. the main component of marine zooplankton) FGs to identify regions sharing similar functional trait expression at the community level.TaxonMarine planktonic Neocopepoda.LocationGlobal ocean.MethodsFactor analysis on mixed data and hierarchical clustering were used to identify copepod FGs based on five species‐level functional traits. An ensemble of species distribution models was used to estimate the environmental niches of the species modelled and the community weighted mean (CWM) values of the traits studied. Ocean regions were defined based on their community‐level mean trait expression using principal component analysis and hierarchical clustering.ResultsEleven global copepods FGs were identified. They displayed contrasting latitudinal patterns in mean annual habitat suitability that could be explained by differences in environmental niche preferences: two FGs were associated with polar conditions, one followed the global temperature gradient, five were associated with tropical oligotrophic gyres and the remaining three with boundary currents and counter currents. Four main regions of varying CWM trait values emerged: the Southern Ocean, the northern and southern high latitudes, the tropical gyres and the boundary currents and upwelling systems.ConclusionsThe present FGs will improve the representation of copepods in global marine ecosystem models. This study improves the understanding of the patterns and drivers of copepods trait biogeography and will serve as a basis for studying links between zooplankton biodiversity and ecosystem functioning in a context of climate change.

Distribution and seasonal spread of zooplankton in Iraqi waters

A summary of zooplankton research done in Peruvian marine waters is presented. We first provide a brief overview of the evolution of zooplankton studies off Peru before reviewing zooplankton biodiversity, regional distribution, seasonal and interannual fluctuation, trophodynamics, secondary production, and modeling are some of these topics. We evaluate research on various meroplankton, macroplankton, mesoplankton, and microplankton groups and provide a list of species from both published and unpublished sources. Three regional zooplankton groups have been identified: · A shelf group on the continental shelf dominated by Acartia tonsa and Centropages brachiatus; · A slope group on the continental shelf with siphonophores, bivalves, foraminifera, and radiolaria · An oceanic group with adiversity of species. Where the continental shelves are thin, between 4-6°S and 14-16°S, the largest zooplankton abundances and biomasses were frequently seen. The diversity of species varies according to distance from the shore. As a result of advection, peaks in larval production, trophic interactions, and community succession, species composition and biomass also change significantly over short time intervals. Based on the detrimental consequences of weak summer upwelling intensity or exceptionally high and persistent winter upwelling on zooplankton abundance off Peru, an intermediate upwelling hypothesis is put forth. This concept states that a window of optimal environmental conditions for zooplankton groups is produced by intermediate upwelling. Finally, we identify significant knowledge gaps that demand future attention.

Spatio-temporal distribution of gelatinous zooplankton in tropical mangrove estuaries: Environmental drivers and possible mangrove disturbance effects

The impacts of environmental changes and mangrove disturbance on the gelatinous zooplankton community structure were investigated monthly for one annual cycle at six stations in three estuaries in Matang, Malaysia. Tiram, Tinggi, and Sepetang estuaries were classified based on the Mangrove Quality Index (MQI) to represent the least (MQI 5 = excellent), moderately (MQI 4 = good), and highly disturbed (MQI 2 = bad) areas, respectively. Among the gelatinous zooplankton species, the holoplanktonic ctenophore, Pukia ohtsukai (formed 56%–58% of the total gelatinous zooplankton), was the most dominant species and showed increased densities with the increasing level of disturbance. On the other hand, a hydrozoan, Blackfordia sp. (39%–43%), which needs suitable substrates for the survival of polyploids, was found to be most abundant in the moderately disturbed area, indicating low densities in areas with too little or too much disturbance. Salinity, a parameter influenced by river discharge and tidal changes, was identified as the main environmental factor affecting the species' seasonal variability. The dry season was associated with an increase in gelatinous zooplankton density and prevalence of marine species. Also, factors related to water clarity (turbidity, transparency, and suspended solids) and nutrients (nitrogen and phosphorus) explained 91% of the variables that affected the gelatinous zooplankton community structure. The species diversity (H′) in the least and moderately disturbed areas were significantly higher than in the highly disturbed estuary. In contrast, the highest mean density was recorded in the highly disturbed estuary (34.4 ± 19.8 inds. m−3) followed by the moderately (21.6 ± 6.1 inds. m−3) and the least disturbed areas (9.7 ± 4.1 inds. m−3). The present study suggested that the gelatinous zooplankton biodiversity declines and the abundance escalates with increasing disturbance levels.

Towards a synthesis of the biodiversity of freshwater Protozoa, Rotifera, Cladocera, and Copepoda in Brazil

Although Brazil is considered a megadiverse country, its rich freshwater biodiversity is still poorly known. A general overview of to-date knowledge on Protozoa, Rotifera, Cladocera, and Copepoda species and distribution in Brazilian Hydrographic Regions is presented here, based on literature data since the 1890s. Ecological studies provided most of the occurrence records. The results show high richness for all studied biological groups and unequal distribution of the occurrence records, which are substantially influenced by research groups’ location. The data also revealed that Brazilian zooplankton biodiversity still needs to be better studied, taxonomically, although from the beginning of the last century until 1980 these kinds of studies were predominant.

Copepods and mixotrophic Rhizaria dominate zooplankton abundances in the oligotrophic Indian Ocean

The large, tropical oligotrophic gyres of the world's oceans are understood to be relatively unproductive, with low phytoplankton and zooplankton biomass, and inefficient food webs, although data are scarce. Here we investigate changes in the zooplankton assemblage along a 15 °C temperature gradient from 20 stations on the 110°E transect as part of the second International Indian Ocean Expedition. To ensure that we reflect most of the zooplankton biodiversity, we used a 100 μm mesh net to capture the small copepod and microzooplankton components that are important and often overlooked in tropical systems. Further, to obtain a synoptic view, we towed the Continuous Plankton Recorder between stations across 30° of latitude. We found that copepod assemblages clustered into four groups, with the most distinct being at the highest latitudes south of the sub-tropical Front. As the ocean temperature increased from south to north along the transect, zooplankton abundance and diversity also increased. The dominant copepod species changed accordingly and were predominantly those with the ability and/or preference to selectively feed on microzooplankton. Although copepods were the most abundant taxon, the proportion of microzooplankton, particularly, mixotrophic Rhizaria, was consistently high. Thus, our study found a highly mixotrophic system supporting secondary production in the oligotrophic Indian Ocean.

Zooplankton Assemblages in a Heavily Polluted River Ecosystem (Pinang River, Malaysia): Impacts of Anthropogenic Stressors on the Communities

River ecosystems are among the most affected habitats globally due to various anthropogenic stressors such as pollution, habitat degradation, hydromorphological alterations and impervious cover due to urbanization. It remains largely unknown how and to what extent zooplankton communities are affected by these stressors in a heavily polluted river ecosystem. This study investigated the abundance and distribution of zooplankton species and the factors affecting their abundance and distribution in Pinang River. A total of 29 taxa of zooplankton were recorded, which includes 27 taxa of Rotifera and two taxa of Copepoda. Among rotifers, the order Bdelloidea had the highest relative abundance (64.79%), followed by Testudinella sp. and Lecane sp. with 10% relative abundance respectively. Spearman’s correlation coefficient showed that the zooplankton abundance was negatively correlated with total dissolved solids and conductivity (P < 0.01). Much higher total dissolved solids and water conductivity, much lower zooplankton abundance. This condition is probably to be unfavorable to the zooplankton population as it is attributed to the presence of extreme anthropogenic activities along the river that cause runoff with high suspended matter. Thus, variations in zooplankton biodiversity reflect the deterioration of water quality in the polluted river ecosystem.

Diel Vertical Distribution of Mesozooplankton Functional Groups in the North Pacific Subtropical Gyre: A Case Study

Understanding the diel vertical migration (DVM) patterns of zooplankton has important implications for biological pumping and pelagic food webs. The functional traits of zooplankton generally determine their distribution in the environment. However, knowledge about the DVM patterns of zooplankton with different functional traits is limited. Here, we used a trait-based approach to study the vertical distributions of zooplankton in the North Pacific Subtropical Gyre (NPSG). Four functional traits, namely, body length, feeding type, trophic group, and reproductive mode, were selected in this study. A high biodiversity of zooplankton (165 taxa) was recorded in the NPSG. Zooplankton was mainly concentrated above 100 m and exhibited normal DVM. Zooplankton with small and medium body sizes (<2 mm, 69% ± 16%), current feeding (43% ± 14%), and omnivore–herbivores (54% ± 14%) were dominant in the NPSG. The proportion of sac spawners in total abundance (52% ± 14%) was higher than that of broadcast spawners (48% ± 14%), which differed from that in the coastal regions. Sixteen functional groups of zooplankton were identified. Different functional groups exhibited distinct DVM patterns due to the influence of different factors. The DVM patterns of current-feeding omnivore–herbivores were significantly correlated with chlorophyll a, whereas giant ambush-feeding carnivores exhibited normal DVM patterns and were substantially correlated with the vertical distribution of their food organisms. However, the small omnivore–carnivores showed reverse DVM patterns. Overall, this study provided a new perspective for studies on zooplankton DVM from the aspect of functional traits.

Connections among Land Use, Water Quality, Biodiversity of Aquatic Invertebrates, and Fish Behavior in Amazon Rivers.

Rivers in the Amazon have among the greatest biodiversity in the world. The Xingu River, one of the tributaries of the Amazon River, has a length of 1640 km, draining 510,000 km2 in one of the most protected regions on the planet. The Middle Xingu region in Brazil has been highly impacted by mining and livestock farming, leading to habitat fragmentation due to altered water quality. Therefore, comparing two rivers (the preserved Xingu River and the impacted Fresco River) and their confluence, the aims of the present study were to (1) assess the land uses in the hydrographic basin; (2) determine the water quality by measurements of turbidity, total solids, and metals (Cd, Cu, Fe, Mn, Pb, Zn, and Hg); (3) compare the zooplankton biodiversity; and (4) to evaluate the avoidance behavior of fish (Astyanax bimaculatus) when exposed to waters from the Xingu and Fresco Rivers. Zooplankton were grouped and counted down to the family level. For the analysis of fish avoidance, a multi-compartment system was used. The forest class predominated at the study locations, accounting for 57.6%, 60.8%, and 63.9% of the total area at P1XR, P2FR, and P3XFR, respectively, although since 1985, at the same points, the forest had been reduced by 31.3%, 25.7%, and 27.9%. The Xingu River presented almost 300% more invertebrate families than the Fresco River, and the fish population preferred its waters (>50%). The inputs from the Fresco River impacted the water quality of the Xingu River, leading to reductions in local invertebrate biodiversity and potential habitats for fish in a typical case of habitat fragmentation due to anthropic factors.

Abundance and Biodiversity of Zooplankton in Salimpur Coast, Bangladesh

Abundance and Biodiversity of Zooplankton in Salimpur Coast, Bangladesh

Biodiversity of zooplankton in 0–3000 ​m waters from the eastern Indian Ocean in spring 2019 based on metabarcoding

To increase knowledge on zooplankton diversity in the deep sea, 42 zooplankton samples (depths of 0–3000 ​m) were taken across five stations throughout the northeastern Indian Ocean using a vertical multi-plankton sampler. According to metabarcoding results of the V4 region of the 18S rRNA gene, Copepoda, Hydrozoa and Malacostraca were present at all stations, while Polychaeta, Scyphozoa, and Thaliacea mainly appeared in the Bay of Bengal. A correlation heatmap showed that the abundance of surface species belonging to Copepoda, Gastropoda, Thaliacea, and Sagittoidea responded most closely to temperature, dissolved oxygen and chlorophyll-a, while the abundance of deep-water species belonging to Thecofilosea, Copepoda, Sagittoidea, and Polychaeta was negatively correlated with temperature, suggesting that temperature differences were driving depth-based variation in zooplankton community distributions in the tropical region. Furthermore, Copepods are important for differentiating depth assemblages in the Indian Ocean. Gaetanus minutus, Lucicutia ovalis, Heterostylites major and Metridia asymmetrica prefer the mesopelagic environment. The vertical distribution of zooplankton diversity showed a bimodal pattern. Generally, communities between 200 and 400 ​m at stations ZS1, ZS3 and ZS4 differed greatly from those of 0–200 ​m. However, at stations ZS2 and ZS5, communities between 200 and 400 ​m had high similarity with those of 0–200 ​m, possibly due to the influence of upwelling. Findings from this study significantly improve our understanding of zooplankton diversity and ecological functions in the deep sea.

DNA宏条形码技术在海洋浮游动物多样性和生态学研究中的应用

DNA宏条形码技术在海洋浮游动物多样性和生态学研究中的应用

Zooplankton diversity in Acre state, Amazon, Brazil: an overview of previous studies

Abstract: This work assesses current knowledge of zooplankton biodiversity in aquatic ecosystems of the state of Acre (Brazil). A bibliographic survey was undertaken, showing that most of the reported studies have focused on zooplankton diversity and composition. Fifteen locations have been studied. There is still a scarcity of information concerning zooplankton populations in the Amazon region. To date, 170 species of planktonic rotifers have been recorded, distributed in 26 families and 38 genera, together with 18 species of cladocerans, distributed in 8 families and 18 genera, and 4 species of copepods in 2 families and 6 genera. The results indicate the need for further research concerning the biodiversity of this group of organisms at locations in the basins of the Purus and Juruá Rivers, especially in lotic ecosystems and littoral zones, given the present lack of information and the socioeconomic importance they play in the region.

Erratum to: New insights into biodiversity, biogeography, ecology, and evolution of marine zooplankton based on molecular approaches

Erratum to: New insights into biodiversity, biogeography, ecology, and evolution of marine zooplankton based on molecular approaches

Corrigendum to: Metabarcoding as a quantitative tool for estimating biodiversity and relative biomass of marine zooplankton

Corrigendum to: Metabarcoding as a quantitative tool for estimating biodiversity and relative biomass of marine zooplankton

Environmental conditions drive zooplankton community structure in the epipelagic oceanic water of the southern Gulf of Mexico: A molecular approach.

Zooplankton plays a pivotal role in sustaining the majority of marine ecosystems. The distribution patterns and diversity of zooplankton provide key information for understanding the functioning of these ecosystems. Nevertheless, due to the numerous cryptic and sibling species and the lack of diagnostic characteristics for early developmental stages, the identification of the global-to-local patterns of zooplankton biodiversity and biogeography remains challenging in different research fields. The spatial and temporal changes in the zooplankton community in the open waters of the southern Gulf of Mexico were assessed using metabarcoding analysis of the V9 region of 18S rRNA and mitochondrial cytochrome oxidase c subunit I (COI). Additionally, a multiscale analysis was implemented to evaluate which environmental predictors may explain the variability in the structure of the zooplankton community. Our findings suggest that the synergistic effects of dissolved oxygen concentration, temperature, and longitude (intended as a proxy for still unidentified predictors) may explain both spatial and temporal zooplankton variability even with low contribution. Furthermore, the zooplankton distribution probably reflects the coexistence of three heterogeneous ecoregions and a bio-physical partitioning of the studied area. Finally, some taxa were either exclusive or predominant with either 18S or COI markers. This may suggest that comprehensive assessments of the zooplankton community may be more accurately met by the use of multilocus approaches.