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.

Under ongoing climate change and increasing anthropogenic activity, which continuously challenge ecosystem resilience, an in-depth understanding of ecological processes is urgently needed. Lakes, as providers of numerous ecosystem services, face multiple stressors that threaten their functioning. Harmful cyanobacterial blooms are a persistent problem resulting from nutrient pollution and climate-change induced stressors, like poor transparency, increased water temperature and enhanced stratification. Consistency in data collection and analysis methods is necessary to achieve fully comparable datasets and for statistical validity, avoiding issues linked to disparate data sources. The European Multi Lake Survey (EMLS) in summer 2015 was an initiative among scientists from 27 countries to collect and analyse lake physical, chemical and biological variables in a fully standardized manner. This database includes in-situ lake variables along with nutrient, pigment and cyanotoxin data of 369 lakes in Europe, which were centrally analysed in dedicated laboratories. Publishing the EMLS methods and dataset might inspire similar initiatives to study across large geographic areas that will contribute to better understanding lake responses in a changing environment.

Author Contribution Statement: D.D. analyzed and worked on data visualization, coordinated feedback from coauthors, and wrote the manuscript. E.M. coordinated the EMLS, collected data, curated the dataset, analyzed the data, and contributed to writing the manuscript. B.I. conceived the idea for the EMLS, contributed to discussions throughout the study and to the writing of the manuscript. D.

Bu çalışmada Türkiye'nin 2.büyük tatlısu gölü olan Eğirdir Gölü'nün mikrobiyolojik parametrelerinin mevsimsel değişiminin izlenmesi amaçlanmıştır. 2013 yılı içerisinde mevsimsel gerçekleştirilen çalışmada göl üzerinde belirlenen 9 istasyondan alınan su örneklerinde toplam koliform, fekal koliform, Escherichia coli (E. coli) ve toplam bakteri analizleri gerçekleştirilmiştir. Çalışma sonucunda göl suyu toplam koliform sayısı 0 ile 34 arasında değişim göstermiştir. Elde edilen değerler limit değerlerin (70 EMS/100 mL) altında olduğu belirlenmiştir. Fekal koliformlar yaz döneminde sadece 4.istasyonda, sonbahar döneminde ise 7. ve 9. istasyonda tespit edilmiştir. Toplam E. coli ise bütün istasyonlarda tespit edilmemiştir. Toplam bakteri sayısı 0 ile 172 kob/100 mL arasında değişim göstermiştir. Elde edilen sonuçlar Yüzeysel Su Kalitesi Yönetimi Yönetmeliği Kıta içi Su Kaynakları Kalite Kriterleri yönüyle değerlendirildiğinde kabul edilebilir değerlerin altında olduğu belirlenmiştir.

In this study the effect of black cumin seed (Nigella sativa) on nonspecific defense mechanisms of rainbow trout (Oncorhynchus mykiss) was investigated. The percentage of black cumin seed in diet were 0.0; 0.5; 1.0; 2.5; 5.0; 10.0 and 20.0 g/kg respectively. Rainbow trout (O. mykiss) of initial weights 108.7±17g were used for experiment. The biometric measurements and the blood parameters were determined in each group after feeding 7, 15, 25, 40 and 60 days respectively. In 7 day experiment, plasma protein, MCH, MCHC, RDW_SD and RDW_CV, MPV values at 1.0 and 2.5 g/kg dose groups differed favorably from the control group. In 15 day feeding experiment, there is a positive mathematical difference in almost all parameters in the 2.5 g/kg dose group compared to control group. In 25 day experiment, there is a positive mathematical difference according to control group in almost all parameters and statistically significant difference between MCH and MPV values in the 2.5 g/kg dose group (P<0.05). In 40 day feeding experiment, plasma protein, MCV, RDW_CV, PLT values differed positively from the control group at the 1.0 and 2.5 g/kg dose groups and mathematical differences were observed in other parameters. In 60 day feeding experiment, at the doses of 1.0 and 2.5 g/kg, many parameters differ from the control group and from the other groups.