Phosphorus–Chlorophyll Relationships under Contrasting Zooplankton Community Structure: Potential Mechanisms

1994 ◽  
Vol 51 (2) ◽  
pp. 401-407 ◽  
Author(s):  
Asit Mazumder
Keyword(s):  
Community Structure ◽  
Chlorophyll A ◽  
Total Phosphorus ◽  
Zooplankton Community ◽  
Opposite Pattern ◽  
Zooplankton Community Structure

Data from experimental enclosures and natural and manipulated lakes were used to test whether the variable chlorophyll a (Chl) yields to total phosphorus (TP) can be explained by the variable contributions of dissolved (TDP) and zooplankton phosphorus (ZP; P > 200 μm) to TP. Results indicate that low Chl yields to TP in systems with abundant large Daphnia are closely related to greater contributions of TDP and ZP to TP. An opposite pattern is produced by systems lacking large Daphnia. These patterns seem to be consistent among mesoeutrophic to hypereutrophic systems; Chl yields to TP decline with increasing contributions of TDP to TP. In the large-Daphnia-dominated systems, both high grazing and reduced phosphate demand allow a greater sequestering of P into zooplankton and dissolved pools rather than in algae, which generate a lower observed Chl yields to TP. Conversely, lack of large Daphnia and low grazing rates allow proliferation of small algae, and an associated intense phosphate demand allows greater sequestering of P into small algae rather than into zooplankton and dissolved pools, and consequently, a higher Chl yield to TP is produced.

Effects of Grazer Community Composition and Fish on Algal Dynamics

1992 ◽  
Vol 49 (9) ◽  
pp. 1908-1915 ◽  
Author(s):  
Andrew M. Turner ◽  
Gary G. Mittelbach
Keyword(s):  
Community Structure ◽  
Factorial Design ◽  
Chlorophyll A ◽  
Community Composition ◽  
Standing Crop ◽  
Zooplankton Community ◽  
The Other ◽  
Light Extinction ◽  
Phytoplankton Abundance ◽  
Zooplankton Community Structure

We examined the effects of grazer community composition and fish on phytoplankton abundance by manipulating zooplankton community structure and the intensity of planktivory in a factorial experiment. Enclosures (1700-L bags) were treated with fish (present/absent) and two grazer communities (one a large-bodied community dominated by Daphnia and the other a small-bodied community dominated by Ceriodaphnia) in a 2 × 2 factorial design. We sampled zooplankton and algae every 4–8 d during the 5-wk experiment. Algal biovolume, chlorophyll a, total particulates, and light extinction were all significantly higher in the presence of fish. Further, the effect of fish on algal standing crop did not depend on which grazer assemblage was initially present. Fish enhanced algal standing crop to the same degree in both Daphnia and Ceriodaphnia treatments. We discuss these results in light of patterns reported in the literature, and the nature of size-structured interactions among fish, zooplankton, and algae.

scholarly journals Spatial variability of zooplankton community structure in Colombian Caribbean waters during two seasons

2018 ◽  
Vol 66 (2) ◽  
Author(s):  
Johanna Medellín-Mora ◽  
Rubén Escribano ◽  
Wolfgang Schneider ◽  
Marco Correa-Ramírez ◽  
Nestor Campos
Keyword(s):  
Community Structure ◽  
Sea Level ◽  
Chlorophyll A ◽  
Environmental Variables ◽  
Stepwise Regression ◽  
Zooplankton Community ◽  
Automated Image Analysis ◽  
Taxonomic Structure ◽  
Zooplankton Abundance ◽  
Zooplankton Community Structure

Zooplankton is an important component to understand oceanographic dynamics, they are considered good indicators of environmental variability, since most species are short-lived they can be tight coupling of climate and population dynamics, and some taxa are sensitive to variables such as temperature, quality and quantity of food, oxygenation and stratification. In the Colombian Caribbean two oceanographic cruises were carried out, in order to characterize and analyze the biodiversity of the continental margin, for the periods May-June 2008 and November-December 2009. The objective of this study was to determine which oceanographic variable was the most important in the distribution of zooplankton in the oceanic waters, and how the variables structure the community. In each cruise, zooplankton samples were obtained by vertical hauls with a 1 m2 diameter conical net (200 μm mesh size). The zooplankton community structure was studied by automated image analysis (ZooImage), which combined with abundance data, allowed to calculate the slope of size spectrum, and diversity indexes of taxa and sizes. The environmental variables included temperature, salinity, oxygen and chlorophyll a of the water column, and were used to calculate the stratification with the Brunt-Vaiisala frequency; this information was complemented by satellite images of temperature, surface chlorophyll, geostrophic currents and sea level, obtained from MODIS and AQUA products. The association between environmental variables and the zooplankton community structure was determined using Spearman’s correlation ranges with the Bioenv routine and a stepwise regression model, and Principal component analysis (PCA). Our results showed spatial and temporal patterns in the oceanographic conditions of the study area, such as upwelling in the Northeast region, strong stratification in the Southwest, and mesoscale activity. The abundance of zooplankton exhibited differences between the two climatic seasons and zones. Temporal differences were also evident in the size and diversity of taxa (ANOVA 2-way p <0.05). These changes were related to the moderate upwelling and the activity of mesoscale eddies. Cyclonic and anticyclonic eddies of variable size can either transport or retain zooplankton over cross-shelf and oceanic areas, thus modifying the taxonomic structure of the community. According to the Bioenv analysis, the main variables that explained the abundance and composition of zooplankton were sea level and chlorophyll a (Spearman correlation = 0.49). The stepwise regression showed that stratification, oxygen and chlorophyll a were the most important predictors of zooplankton abundance and size. Rev. Biol. Trop. 66(2): 688-708. Epub 2018 June 01. 

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

1984 ◽  
Vol 41 (7) ◽  
pp. 1089-1096 ◽  
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.

THE STUDY ON THE EFFECT OF ELODEA NUTTALLII TO ZOOPLANKTON COMMUNITY STRUCTURE

2009 ◽  
Vol 33 (3) ◽  
pp. 556-561
Author(s):  
Gui-Jun YANG ◽  
Bo-Qiang QIN ◽  
Guang GAO ◽  
Xiao-Dong WANG ◽  
Hong-Yan WANG
Keyword(s):  
Community Structure ◽  
Zooplankton Community ◽  
Elodea Nuttallii ◽  
Zooplankton Community Structure

Crustacean zooplankton community structure in temporary and permanent grassland ponds

Hydrobiologia ◽  
2009 ◽  
Vol 632 (1) ◽  
pp. 225-233 ◽  
Author(s):  
S. Matthew Drenner ◽  
Stanley I. Dodson ◽  
Ray W. Drenner ◽  
John E. Pinder III
Keyword(s):  
Community Structure ◽  
Zooplankton Community ◽  
Crustacean Zooplankton ◽  
Zooplankton Community Structure ◽  
Permanent Grassland

scholarly journals Interaction between simulated dense Scenedesmus dimorphus (Chlorophyta) bloom and freshwater meta-zooplankton community

2018 ◽  
Vol 77 (2) ◽  
Author(s):  
Zengling Ma ◽  
Hengguo Yu ◽  
Ronald Thring ◽  
Chuanjun Dai ◽  
Anglv Shen ◽  
...  
Keyword(s):  
Community Structure ◽  
Green Algae ◽  
Aquatic Ecosystems ◽  
Algal Blooms ◽  
Algal Bloom ◽  
Photochemical Efficiency ◽  
Zooplankton Community ◽  
Post Inoculation ◽  
Zooplankton Community Structure ◽  
Scenedesmus Dimorphus

Algal bloom has been a subject of much research, especially the occurrence of blue-green algae (cyanobacteria) blooms and their effects on aquatic ecosystems. However, the interaction between green algae blooms and zooplankton community was rarely investigated. In the present study, the effects exerted by Scenedesmus dimorphus (green alga) bloom on the community structure of zooplankton and the top-down control of the bloom process mediated by the zooplankton were evaluated using a series of laboratory cultures. The results showed that a dense S. dimorphus bloom could change the zooplankton community structure by decreasing its diversity indices, leading to the enrichment of a particular zooplankton species, Brachionus calyciflorus. In the presence of mixed species of zooplankton, the density of S. dimorphus in the culture was decreased as determined by a change in total chlorophyll a (Chl a) concentration, which was about 200 μg L-1 lower than that of the zooplankton-free culture. Furthermore, the number of species belonging to Cladocera, Copepoda and Rotifera all decreased, with all the cladocerans disappeared in the co-culture within 2 weeks of culturing, while the density of rotifers increased from 818 (±243) ind L-1 at the time of inoculation to 40733 (±2173) ind L-1 on the 14th day post-inoculation. Grazing of S. dimorphus by the rotifer B. calyciflorus neutralized its growth, and the gradual increase in B. calyciflorus density eventually led to the collapse of the bloom. Furthermore, grazing by B. calyciflorus also led to a decrease in the maximal photochemical efficiency (Fv/Fm) of photosystem II (PSII). The combined changes occurring in the zooplankton community structure during the process of S. dimorphus bloom and the negative effects of grazing on algal growth, morphology and photosynthetic activities confirmed the key role of zooplankton in the control of algal bloom. The results of the study therefore indicated that dense algal blooms caused by non-toxic algae could still remain a threat to aquatic ecosystems.

scholarly journals Impact of fish cage-culture on the community structure of zooplankton in a tropical reservoir

2011 ◽  
Vol 101 (1-2) ◽  
pp. 75-84 ◽  
Author(s):  
Juliana D Dias ◽  
Érica M Takahashi ◽  
Natália F Santana ◽  
Cláudia C Bonecker
Keyword(s):  
Community Structure ◽  
Food Availability ◽  
Community Dynamics ◽  
Zooplankton Community ◽  
Fish Farming ◽  
Spatial And Temporal Variation ◽  
Cage Culture ◽  
Tropical Reservoir ◽  
Zooplankton Community Structure ◽  
The Impact

We investigated the impact of fish cage culture on the zooplankton community structure in a tropical reservoir. We hypothesized that community abundance is greater near cages and increases over time due to the increase in food availability. Samplings were performed near, upstream and downstream from net cages, and before and after net cage installation. The abundance of zooplankton increased 15 days after the experiment was set up, followed by a reduction and finally increased. Rotifer abundance showed significant differences among sites (p<0.05) and sampling periods (p<0.001). Significant differences were also observed in total zooplankton and cladoceran abundance (p<0.001). The spatial and temporal variation of the physical and chemical variables were indirectly correlated with the structure and dynamic of the zooplankton community, as they indicated the primary production in the environment. Our hypothesis was rejected, since the zooplankton was abundant at the reference site. Only rotifers showed higher abundance near cages, due to the influence of food availability. Community dynamics during the experiment was also correlated to food availability. Our results suggest an impact of fish farming on the zooplankton community.

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