Seasonal Dynamics of the Zooplankton Community in the Temperate Eutrophic Caygoren Reservoir (Balikesir), Turkey Related to Certain Physicochemical Parameters of Water

Seasonal dynamics in the zooplankton community and its relationships with certain physicochemical parameters (water temperature, Secchi disk transparency, conductivity, nitrate-nitrogen (NO3-N), phosphate (PO4), pH, oxidation-reduction potential (ORP) and chlorophyll-a) were studied in the eutrophic Caygoren Reservoir, Turkey from February 2007 to March 2008. Cyclops vicinus was dominant throughout the year; Acanthocyclops robustus was dominant in fall and summer; Asplanchna priodonta was dominant in fall, winter and spring at all stations. Canonical correspondence analysis (CCA) showed that A. robustus had high correlations to conductivity, C. vicinus to PO4 and NO3-N and Metacyclops gracilis to water temperature and chl-a. The number of individual were significantly different among the seasons and stations (P0.05). Zooplankton community in the Caygoren Reservoir underwent changes in species composition from small-bodie

Effects of two synthetic pyrethroids on Arthrospira platensis Gomont growth and antioxidant parameters

The transport of pesticides from application areas to other areas results in pesticide contamination and this sort of contamination has led to unexpected environmental problems worldwide. It is important to determine the responses of phytoplanktonic organisms to these chemicals for an understanding of the effects of pesticides on aquatic ecosystems. In this study, Arthrospira platensis Gomont cyanobacteria were exposed to different concentrations of the pesticides cypermethrin (0-50 µg mL-1) and deltamethrin (0-2 µg mL-1). Changes in chlorophyll-a concentration, the absorbance of OD560, antioxidant parameters (SOD, APX, GR, MDA, H2O2, and proline) were determined under the pesticide exposure. Our results showed that there is a decrease in OD560 absorbance and chlorophyll-a content proportionate to the increase of pesticide levels. Superoxide dismutase enzyme activity decreased with Cyp and Dlm application in A. platensis cultures. Glutathione reductase enzyme activity also decreased with Cyp applications but did not change with Dlm application. Ascorbate peroxidase enzyme activity increased with Cyp treatments but did not change with Dlm applications. Although malondialdehyde and hydrogen peroxide contents did not change with Cyp applications, they increased with Dlm applications. Proline contents increased with Cyp applications but decreased with Dlm applications. In conclusion, deltamethrin is more toxic than cypermethrin in the concentrations applied

Temperature Effects Explain Continental Scale Distribution of Cyanobacterial Toxins

Insight into how environmental change determines the production and distribution of cyanobacterial toxins is necessary for risk assessment. Management guidelines currently focus on hepatotoxins (microcystins). Increasing attention is given to other classes, such as neurotoxins (e.g., anatoxin-a) and cytotoxins (e.g., cylindrospermopsin) due to their potency. Most studies examine the relationship between individual toxin variants and environmental factors, such as nutrients, temperature and light. In summer 2015, we collected samples across Europe to investigate the effect of nutrient and temperature gradients on the variability of toxin production at a continental scale. Direct and indirect effects of temperature were the main drivers of the spatial distribution in the toxins produced by the cyanobacterial community, the toxin concentrations and toxin quota. Generalized linear models showed that a Toxin Diversity Index (TDI) increased with latitude, while it decreased with water stability. Increases in TDI were explained through a significant increase in toxin variants such as MC-YR, anatoxin and cylindrospermopsin, accompanied by a decreasing presence of MC-LR. While global warming continues, the direct and indirect effects of increased lake temperatures will drive changes in the distribution of cyanobacterial toxins in Europe, potentially promoting selection of a few highly toxic species or strains.Peer reviewe

Twenty New Records for Turkish Freshwater Algal Flora from Caygoren and Ikizcetepeler Reservoirs (Balikesir, Turkey)

Twenty new records for freshwater algal flora of Turkey were determined in a study conducted from February 2007 to January 2009 in Ikizcetepeler and Caygoren Reservoirs, Balikesir, Turkey. Among these new records, 4 were Bacillariophyta, 7 were Chlorophyta, 3 were Streptophyta, 1 was Cryptophyta, 3 were Dinophyta, 1 was Euglenophyta and 1 was Heterokontophyta

The Effects of Certain Physical and Chemical Variables on the Succession of the Phytoplankton in the Shallow Cagis Pond (Balikesir, Turkey)

The effects of certain physical and chemical variables on the phytoplankton succession in the shallow cagis Pond (Balikesir, Turkey) were investigated between August 2006 and July 2008. Samples were taken monthly from one sampling station. A total of 93 taxa belonging to 7 divisions were identified, including Chlorophyta (39 taxa), Heterokontophyta (30 taxa), Cyanobacteria (17 taxa), Euglenophyta (2 taxa), Dinophyta (2 taxa), Charophyta (2 taxa) and Cryptophyta (1 taxa). Cyclotella meneghiniana, Microcystis aeruginosa, Microcystis protocystis, Arthrospira platensis, and Micractinium pusillum dominated the phytoplankton at least for one season. A Canonical Correspondence Analysis (CCA) showed that water temperature, transparency conductivity, and total dissolved solids had significant effects on the distribution and abundance of the dominant phytoplankton taxa

SEASONAL VARIATIONS IN THE LENGTH OF ZOOPLANKTON RELATED TO CERTAIN PHYSICOCHEMICAL VARIABLES IN TWO FRESHWATER RESERVOIRS

Seasonal variations in the body length of zooplankton were studied in relation to water temperature, nitrate (NO3), soluble reactive phosphorus (SRP), total chlorophyll, Secchi disk depth, pH, conductivity, and oxidation-reduction potential (ORP) in a mesotrophic (Ikizcetepeler) and a eutrophic (Caygoren) reservoir from February 2007 to March 2008. During the study, the body lengths of a total of 7590 zooplankton specimens (1110 rotifers, 3270 cladocerans, and 3210 copepods) were measured. The length of the majority of the species was significantly smaller in summer than in winter, fall, and spring, including that of the most dominant species, Asplanchna priodonta, Daphnia galeata, Daphnia longispina, Diaphanosoma brachyurum, Bosmina longirostris, Leptodora kindtii, Ceriodaphnia pulchella, Cyclops vicious, Metacyclops gracilis, and Acanthocyclops robustus (F > 5, p < 0.05). Correspondence analysis (CA) showed that the body length of the zooplankton studied was inversely related to water temperature, whereas it was positively related to ORP and pH. The results of our study suggest that, although nutrients (NO3 and SRP) apparently have an effect on zooplankton body length only in the mesotrophic reservoir, temperature influences the body length in both the mesotrophic and the eutrophic reservoir

Phytoplankton dynamics and structure, and ecological status estimation by the Q assemblage index: a comparative analysis in two shallow Mediterranean lakes

The aim of this research was to compare the phytoplankton structure on the basis of environmental variables and test the Q assemblage index based on phytoplankton functional groups in two shallow Mediterranean lakes [ Lake Taskisigi (LT) and Lake Little Akgol (LLA)] in the north of Turkey. Variations in the phytoplankton structure and environmental parameters were analyzed monthly at two stations of each lake between January 2013 and December 2013. We showed that total phosphorus (TP) values were vital in shaping phytoplankton biomass in eutrophic LLA. Nitrate-nitrogen (NO3-N), TP, z(mix)/z(eu), and macrophyte coverage are important in shaping the differences in dominant phytoplankton functional groups between two lakes. Generally, diversity values were similar between the two lakes and environmental parameters had no effect on diversities to constitute significant differences. The assessment using the Q index gave compatible results for determining the ecological status of LT and LLA

BENTHIC DIATOMS AS INDICATORS OF WATER QUALITY IN THE ACARLAR FLOODPLAIN FOREST (NORTHERN TURKEY)

The structure and diversity of the epilithic and epiphytic diatom community and their relationship with the physicochemical parameters of the Acarlar Floodplain Forest were studied. Also, diatom indices and their applicability as a tool for estimating the floodplain water quality were tested. Diatoms were sampled monthly from February 2011 to January 2012 at three sites. A total of 94 taxa were identified. Approximately 76% of the diatom taxa are cosmopolitan distribution for Turkey. The diatom ecological indicator values, Trophic Diatom Index (TDI), Saprobic Index (SI), Swiss Diatom Index (DI-CH), the "Indice de polluo-sensibilite' spe'cifique", also named IPS and Trophic Diatom Index for Lakes (TDIL) were evaluated. TDI, SI and TDIL showed good relationships with environmental variables. A principal component analysis (PCA) was performed on environmental data. The results of PCA separated the second station with high specific conductance, hardness and NO3-N concentrations. It also showed that physicochemical parameters were affected by temperature and water level. Canonical Correspondence Analysis (CCA) was carried to determine the relationship between the diatom distributions and environmental variables. The results of CCA bi plot showed that specific conductance, hardness, turbidity, pH, dissolved oxygen, oxygen saturation and nutrients were significantly correlated with species distribution. According to the CCA result, two diatom groups were separated

The phytoplankton functional group concept provides a reliable basis for ecological status estimation in the Caygoren Reservoir (Turkey)

The phytoplankton functional group (FG) concept has been successfully used to determine water quality states in both lake and river systems, but is not yet stressed in regular studies in reservoir environments. The purpose of our study was to estimate the ecological status of the temperate Caygoren Reservoir (2007-2009) using the Q((r)) FG composition metric, and to test whether it is able to follow the main structuring of the physical and chemical parameters studied. The main occurring coda were codon C (Cyclotella meneghiniana Kutzing, Stephanodiscus neoastraea Hakansson and Hickel), codon T (Gloeotila subconstricta (G.S. West) Printz, Mougeotia sp.), codon X2 (Cryptomonas pyrenoidifera Geitler, Plagioselmis nannoplanctica (H.Skuja) G.Novarino, I.A.N.Lucas and S.Morrall), codon K (Aphanocapsa holsatica (Lemmermann) G.Cronberg and J.Komarek, Aphanothece clathrata West and G.S. West), and codon S1 (Planktothrix sp.). The seasonal succession of phytoplankton displayed the lake-like coda series of Y (winter) -> C (spring) -> K/S1 (summer) -> T (fall) in each year, which demonstrated well the transitional behavior of reservoirs between lake and river ecosystems. The FG compositions showed high relationships with water temperature, ammonia, phosphate, and light availability in this temperate reservoir, where the Q((r)) index estimated reliable water quality states between hypertrophic and oligotrophic conditions

The Seasonal and Spatial Distribution of the Phytoplankton of a Mesotrophic Lake Related to Certain Physical and Chemical Parameters

The seasonal and spatial distribution of the phytoplankton and their relationship with physicochemical parameters of Lake Poyrazlar, a mesotrophic lake located in Northwest Turkey, was studied monthly between April 2011 and March 2012. A total of 120 taxa in 7 divisions were identified during the study. The planktonic algae of Lake Poyrazlar was dominated by Cyanobacteria in the summer, Charophyta in the fall, diatoms and Cryptophyta in the winter, and Chlorophyta in the spring. The relationships between water temperature, pH, specific conductance, dissolved oxygen, Secchi disk depth (transparency), Chl-a, nitrate-nitrogen (NO3-N), nitrite-nitrogen (NO2-N), total phosphorus (TP), orthophosphate (PO4-P), silica (Si), sulfate (SO4) concentrations, and the abundance of dominant species were explored using the statistical method of Canonical Correspondence Analysis (CCA). The CCA results showed that the most important factors affecting the distribution of phytoplankton were the concentrations of the main nutrients, water temperature, and underwater light