Widespread agrochemicals differentially affect zooplankton biomass and community structure

AbstractAnthropogenic environmental change is causing habitat deterioration at unprecedented rates in freshwater ecosystems. Despite increasing more rapidly than other agents of global change, synthetic chemical pollution –including agrochemicals such as pesticides– has received relatively little attention in freshwater biotic assessments. Determining the effects of multiple agrochemicals on complex community and ecosystem properties remains a major challenge, requiring a cross-field integration of ecology and ecotoxicology. Using a large-scale array of experimental ponds, we investigated the response of zooplankton community properties (biomass, composition, diversity metrics) to the individual and joint presence of three widespread agrochemicals: the herbicide glyphosate, the neonicotinoid insecticide imidacloprid, and fertilisers. We tracked temporal variation in community biomass and structure (i.e., composition, diversity metrics) along single and combined pesticide gradients (each spanning eight levels), under low (mesotrophic) and high (eutrophic) nutrient-enriched conditions, and quantified (i) agrochemical interactions, (ii) response threshold concentrations, and (iii) community resistance and recovery. We found that major zooplankton groups differed in their sensitivity to pesticides: ≥3 µg/L imidacloprid impaired copepods, rotifers collapsed at glyphosate levels ≥0.3 mg/L, whereas some cladocerans were highly tolerant to pesticide contamination. Glyphosate was the most influential driver of community properties, with biomass and community structure responding rapidly but recovering unequally over time. Zooplankton biomass showed little resistance when first exposed to glyphosate, but rapidly recovered and even increased with glyphosate concentration; in contrast, richness declined in more contaminated ponds but failed to recover. Our results show that the biomass of tolerant taxa compensated for the loss of sensitive species, conferring greater resistance upon subsequent exposure; a rare example of pollution-induced community tolerance in freshwater metazoans. Overall, zooplankton biomass appears to be more resilient to agrochemical pollution than community structure, yet all community properties measured in this study were affected at glyphosate levels below common water quality guidelines in North America.

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Zooplankton Seasonal Dynamics and Community Structure in Severn Sound, Lake Huron

Water Quality Research Journal ◽

10.2166/wqrj.1995.049 ◽

1995 ◽

Vol 30 (4) ◽

pp. 673-692

Author(s):

A.F. Gemza

Keyword(s):

Community Structure ◽

Zooplankton Community ◽

Zooplankton Biomass ◽

Point Sources ◽

Total Zooplankton ◽

Fish Community Structure ◽

Calanoid Copepods ◽

Diacyclops Thomasi ◽

Annual Means ◽

Total Zooplankton Biomass

Abstract The limnetic zooplankton of Severn Sound, a eutrophic embayment, were studied between 1978 and 1989. Forty-one species of zooplankton were identified from samples collected in the sound. Total zooplankton biomass ranged seasonally from a minimum of 3.9 mg/m3 at less eutrophic stations to over 1,625 mg/m3 at the most eutrophic sites. Annual means ranged from 38 to 373 mg/m3. At the most eutrophic sites the zooplankton community was dominated by the cladoceran Bosmina longirostris. Cyclopoid and calanoid copepods increased in dominance as conditions approached mesotrophy. Calanoid copepods were insignificant contributors at the eutrophic sites, averaging less than 3% of the total zooplankton biomass. Total zooplankton biomass declined with distance from shore and phosphorus point sources as conditions became less eutrophic. Significant empirical relationships (r>0.79) were measured between zooplankton biomass and total phosphorus and phytoplankton biovolume. Densities of several species, Eubosmina coregoni, Daphnia retrocurva and Diacyclops thomasi declined by over 50% during the 11-year period of study and may be related to a shift in fish community structure.

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Calcium decline reduces population growth rates of zooplankton in field mesocosms

Canadian Journal of Zoology ◽

10.1139/cjz-2016-0105 ◽

2017 ◽

Vol 95 (5) ◽

pp. 323-333 ◽

Cited By ~ 6

Author(s):

S.E. Arnott ◽

S.S.E. Azan ◽

A.J. Ross

Keyword(s):

Community Structure ◽

Growth Rates ◽

Large Scale ◽

Zooplankton Community ◽

Aquatic Organisms ◽

Potential Threat ◽

Zooplankton Community Structure ◽

Population Growth Rates ◽

South Central ◽

Mesocosm Experiments

Regional calcium (Ca) decline, a legacy of acid deposition and logging, is a potential threat to aquatic organisms. Lake surveys and laboratory studies indicate that Ca-rich daphniids are likely most susceptible, allowing for competitive release of other taxa with low Ca demand. Indeed, dramatic shifts in zooplankton community structure have been documented in lakes where Ca has declined, amid multiple other stressors. Given the perceived threat of this large-scale stressor, manipulative studies are needed to evaluate causal relationships between Ca decline and zooplankton community structure. We analysed per capita growth rates of zooplankton from three independent mesocosm experiments where we manipulated aqueous Ca concentrations to reflect current and future Ca concentrations. In two experiments where Ca concentration was reduced to 0.6 or 0.9 mg/L, we observed reduced growth rates for several taxa, including daphniids, bosminids, and copepods. No effect of Ca was detected in the experiment where Ca concentrations ranged from 1.2 to 2.5 mg/L, a gradient representing 68% of lakes in south-central Ontario. These results suggest that future Ca decline in soft-water Canadian Shield lakes may be accompanied by shifts in community structure and overall declines in zooplankton production.

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Impact of habitat heterogeneity on the biodiversity and density of the zooplankton community in shallow wetlands (Upo wetlands, South Korea)

Oceanological and Hydrobiological Studies ◽

10.1515/ohs-2016-0041 ◽

2016 ◽

Vol 45 (4) ◽

Cited By ~ 6

Author(s):

Jong-Yun Choi ◽

Kwang-Seuk Jeong ◽

Seong-Ki Kim ◽

Gea-Jae Joo

Keyword(s):

South Korea ◽

Zooplankton Community ◽

Open Water ◽

Structural Heterogeneity ◽

Taxonomic Composition ◽

Zooplankton Biomass ◽

Freshwater Ecosystems ◽

Habitat Types ◽

Vegetation Zone ◽

Zooplankton Density

AbstractMacrophytes play a major role in the structuring of aquatic environments, and create diverse microhabitats. Therefore, these plants represent an important factor regulating the zooplankton biomass, taxonomic composition, and distribution in freshwater ecosystems. In the current study, we examined the effects of the structural heterogeneity provided by various macrophytes. We identified four habitat types in this study: (1) open water (without macrophytes), (2) the helophyte zone, (3) the pleustophyte zone, and (4) the mixed vegetation zone (containing pleustophytes, nymphaeids, and elodeids). We tested the hypothesis that complex habitat structures support large zooplankton assemblages. Specifically, we collected zooplankton samples from a total of 119 sampling points in the Upo Wetlands, South Korea, during the spring and autumn of 2009. The largest zooplankton assemblage was found in the mixed macrophyte zone, followed by the helophyte and pleustophyte zones. The pleustophyte zone supported larger zooplankton assemblages during autumn compared to spring. Differences in zooplankton assemblages were considered to be strongly related to seasonal variation in the development and growth of pleustophytes. However, two-way ANOVA revealed that seasons had no significant influence on the zooplankton density and diversity. Instead, different habitat types substantially determined zooplankton characteristics. In conclusion, we demonstrated that wetland areas with high macrophyte species diversity contribute toward higher zooplankton diversity.

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Zooplankton Community Structure in Shallow Saline Steppe Inland Waters

Water ◽

10.3390/w13091164 ◽

2021 ◽

Vol 13 (9) ◽

pp. 1164

Author(s):

Katalin Zsuga ◽

Zarina Inelova ◽

Emil Boros

Keyword(s):

Community Structure ◽

Large Scale ◽

Zooplankton Community ◽

Extreme Environment ◽

Baseline Survey ◽

Inland Waters ◽

High Concentration ◽

Regional Study ◽

Zooplankton Community Structure ◽

Saline Waters

Several shallow saline waters can be found in Central Asia in arid steppe climate, but our knowledge of their zooplankton community has been so far rather limited. The aim of our research was to provide data on the steppe zooplankton community in a large-scale regional study. Therefore, a baseline survey was carried out in 23 shallow inland waters of different salinity in Northern Kazakhstan. We measured the quantity and identified the taxonomic composition of zooplankton in the spring period and examined changes in community structure in correlation with salinity. Lesser salt concentration of the hyposaline–mesosaline waters was indicated by the presence of halophilic rotifer species: Brachionus asplanchnoides, Br. dimidiatus, Br. plicatilis. Mesosaline and hypersaline waters were indicated by the presence of halobiont crustaceans: Moina salina, Arctodiaptomus salinus, Cletocamptus retrogressus. Very high concentration of salt was indicated by presence of Artemia alone which is the only group, that can tolerate and adapt to this extreme environment. In the hypersaline waterbodies at over 79 gL−1 high TDS conditions a very simple tropical structure was found. Artemia playing monopolistic ecological function in the zooplankton community. We identified three characteristic groups of shallow inland saline waters based on their zooplankton composition.

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Impact of Bythotrephes invasion on zooplankton communities in acid-damaged and recovered lakes on the Boreal Shield

Canadian Journal of Fisheries and Aquatic Sciences ◽

10.1139/f05-152 ◽

2005 ◽

Vol 62 (11) ◽

pp. 2450-2462 ◽

Cited By ~ 26

Author(s):

Angela L Strecker ◽

Shelley E Arnott

Keyword(s):

Community Structure ◽

Zooplankton Community ◽

Freshwater Ecosystems ◽

Specific Response ◽

Bythotrephes Longimanus ◽

Aquatic Communities ◽

Zooplankton Community Structure ◽

Community Types ◽

Zooplankton Communities ◽

The Impact

Invasive species introductions into freshwater ecosystems have had a multitude of effects on aquatic communities. Few studies, however, have directly compared the impact of an invader on communities with contrasting structure. Historically high levels and subsequent reductions of acid deposition have produced landscapes of lakes of varying acidity and zooplankton community structure. We conducted a 30-day enclosure experiment in Killarney Provincial Park, Ontario, Canada, to test the effects of Bythotrephes longimanus, an invasive invertebrate predator, on two contrasting zooplankton communities at different stages of recovery from acidification: recovered and acid damaged. Bythotrephes significantly decreased zooplankton biomass and abundance in both communities but had a greater negative effect on the abundance of zooplankton in the recovered community. Bythotrephes reduced species diversity of the recovered zooplankton community but not of the acid-damaged community. Species richness of both community types was unaffected by Bythotrephes predation. The effect of Bythotrephes on small cladocerans, a preferred prey type, differed between the community types and appeared to be related to density-dependent predation by Bythotrephes. Both community- and species-level results suggest that recovered and acid-damaged zooplankton assemblages may be negatively affected by an invasion of Bythotrephes but that the specific response is dependent on the original community structure.

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Zooplankton Community Structure, but not Biomass, Influences the Phosphorus–Chlorophyll a Relationship

Canadian Journal of Fisheries and Aquatic Sciences ◽

10.1139/f84-128 ◽

1984 ◽

Vol 41 (7) ◽

pp. 1089-1096 ◽

Cited By ~ 103

Author(s):

Michael L. Pace

Keyword(s):

Community Structure ◽

Body Size ◽

Chlorophyll A ◽

Zooplankton Community ◽

Zooplankton Biomass ◽

Similar Data ◽

Data Set ◽

Zooplankton Community Structure ◽

Chl A ◽

Residual Variation

Simultaneous observations were made of total phosphorus (TP), chlorophyll a (Chl a), and zooplankton biomass and community structure at 12 sites in the Eastern Townships (ET) region of Quebec to determine if zooplankton parameters reduced residual variation in the TP–Chl a relationship. Similar data from three stations in Lake Memphremagog and the literature were also analyzed. Zooplankton biomass was not significant in explaining residual variation in the TP–Chl a relationship of any data set studied. The mean body size of cladocerans was also not a significant additional variable in a TP–Chl a model based on the seasonal mean values in the ET lakes, but cladoceran body size was a significant factor in 13 lakes of the Indian River district of New York. The difference between these results is attributed to the rarity of large daphnids in the ET lakes. An index of zooplankton community structure derived from the slope of log abundance–log weight regressions was significant in explaining residual variation in TP–Chl a relationships for the among- and within-lake data and improved the predictive capability of TP–Chl a models. Lakes with higher concentrations of macrozooplankton relative to microzooplankton have less Chl a per unit TP. These results extend the generality of the hypothesis that large zooplankton differentially reduce Chl a relative to TP. In the ET lakes the effect of zooplankton size structure, however, was weak and this suggests that manipulation of zooplankton community structure to manage algal biomass may be of limited value in many lakes.

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