Life history characteristics of a potential invasive Ponto-Caspian goby, Neogobius fluviatilis in natural lakes from its native range (Black Sea region of Turkey)

To fill the gap in and provide baseline knowledge for developing increased understandings of the factors driving the invasiveness of the Ponto-Caspian gobiid Neogobius fluviatilis, their life history traits (as somatic growth and reproduction) were studied in three natural freshwater lakes in its native range. These populations were characterised by slow somatic growth rates, being the slowest reported across all of their native and non-native ranges. Ages were recorded to seven years old. Across the three lakes, there was considerable variability in their sex ratios and reproductive traits (including length at maturity and fecundity at length and age), revealing considerable inter-population variability. These data thus suggest N. fluviatilis has considerable plasticity in the expression of their life history traits, with this plasticity argued as a key factor in facilitating their ability to establish and invade new waters following introductions

Distribution of Spoligotyping Defined Genotypic Lineages among Drug-Resistant Mycobacterium tuberculosis Complex Clinical Isolates in Ankara, Turkey

Background: Investigation of genetic heterogeneity and spoligotype-defined lineages of drug-resistant Mycobacterium tuberculosis clinical isolates collected during a three-year period in two university hospitals and National Tuberculosis Reference and Research Laboratory in Ankara, Turkey. Methods and Findings: A total of 95 drug-resistant M. tuberculosis isolates collected from three different centers were included in this study. Susceptibility testing of the isolates to four major antituberculous drugs was performed using proportion method on Löwenstein–Jensen medium and BACTEC 460-TB system. All clinical isolates were typed by using spoligotyping and IS6110-restriction fragment length polymorphism (RFLP) methods. Seventy-three of the 95 (76.8%) drug resistant M. tuberculosis isolates were isoniazid-resistant, 45 (47.4%) were rifampicin-resistant, 32 (33.7%) were streptomycinresistant and 31 (32.6%) were ethambutol-resistant. The proportion of multidrug-resistant isolates (MDR) was 42.1%. By using spoligotyping, 35 distinct patterns were observed; 75 clinical isolates were grouped in 15 clusters (clustering rate of 79%) and 20 isolates displayed unique patterns. Five of these 20 unique patterns corresponded to orphan patterns in th

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

Hipertrofik bir lagünün restorasyon amaçlı su kalitesi yönetimi çabalarına tepkisi ve ötrofik koşullardan kurtulmayı hızlandırmak için daha fazla restorasyon işlemlerinin araştırılması

RESPONSE OF A HYPERTROPHIC LAGOON TO RESTORATION AIMED WATER QUALITY MANAGEMENT EFFORTS AND INVESTIGATION OF FURTHER RESTORATION OPERATIONS TO ACCELERATE THE RECOVERY FROM EUTROPHIC CONDITIONSErturk A.*, Gürevin C., Albay M.Istanbul University, Faculty of Aquatic Sciences ~ Istanbul ~ TurkeyCoastal lagoons are subjected to many pollution threads including organic matter loads, nutrient loads which may result in several water quality problems and environmental symptoms such as hypoxia or eutrophication, which eventually lead to loss of ecological functions and beneficial uses of the lagoon. Coastal ecosystems with a partly urban and partly rural drainage areas are subjected to a diversity of point and diffuse pollution sources such as domestic and industrial wastewater discharges, urban drainage outflows, runoff from rural settlements and agricultural areas. Küçükçekmece Lagoon is a coastal lagoon locacated in Istanbul, one of the largest metropoles of Europe. It is deep enough for seasonal stratification. All of the watershed of lagoon is located in the province of Istanbul where 26% is located in the urban area and 74% is located in the rural area. The lagoon had been subjected to high nutrient and organic matter loads from late 70s through three main streams and reached a hypertrophic state. This long-term study analyzes the pollution and the progressing recovery of the lagoon from its eutrophic state for more than a decade from the year 2006 up today (2019) and proposes possible restoration techniques to accelerate recovery of the lake from its hypertrophic state

Predicting the effects of sediment based internal nutrient loads on eutrophication in Kucukcekmece Lagoon for rehabilitation planning

In deep stratified coastal lagoons, hypoxic waters that result from phytoplankton decomposition in the stratified bottom waters are often associated with eutrophication. Decomposing biomass reaches the bottom sediments and enriches them with nutrients and organic matter. Nutrients trapped in sediments are released with time and promote excessive phytoplankton growth in the surface water. Because eutrophication in lentic ecosystems progresses in a self-fuelling cycle, outflow is the only available process for exporting excess nutrients to recover from eutrophication. Thus, rehabilitation of eutrophic coastal lagoons that have limited seawater interactions is a long term process. The importance of nutrient release from sediments on eutrophication and the delay effect of internal nutrient loading on the rehabilitation of a eutrophic coastal lagoon with limited seawater exchange were analysed in this study. An ecological model that couples the water column and the sediment diagenesis processes, was developed for water quality management purposes. Our findings indicate that the recovery of the Lagoon from eutrophication will be taken decades even in the absence of external nutrient loading. Therefore, we suggest applying rehabilitation strategies that control the nutrient fluxes from sediments for a faster recovery from heavily eutrophic conditions. Land-based nutrient sources must also be controlled because they feed water column and the bottom sediments with nutrients. (C) 2017 International Research and Training Centre on Erosion and Sedimentation/the World Association for Sedimentation and Erosion Research. Published by Elsevier B.V. All rights reserved

RESPONSE OF A HYPERTROPHIC LAGOON TO RESTORATION AIMED WATER QUALITY MANAGEMENT EFFORTS AND INVESTIGATION OF FURTHER RESTORATION OPERATIONS TO ACCELERATE THE RECOVERY FROM EUTROPHIC CONDITIONS

RESPONSE OF A HYPERTROPHIC LAGOON TO RESTORATION AIMED WATER QUALITY MANAGEMENT EFFORTS AND INVESTIGATION OF FURTHER RESTORATION OPERATIONS TO ACCELERATE THE RECOVERY FROM EUTROPHIC CONDITIONSErturk A.*, Gürevin C., Albay M.Istanbul University, Faculty of Aquatic Sciences ~ Istanbul ~ TurkeyCoastal lagoons are subjected to many pollution threads including organic matter loads, nutrient loads which may result in several water quality problems and environmental symptoms such as hypoxia or eutrophication, which eventually lead to loss of ecological functions and beneficial uses of the lagoon. Coastal ecosystems with a partly urban and partly rural drainage areas are subjected to a diversity of point and diffuse pollution sources such as domestic and industrial wastewater discharges, urban drainage outflows, runoff from rural settlements and agricultural areas. Küçük Çekmece Lagoon is a coastal lagoon locacated in Istanbul, one of the largest metropoles of Europe. It is deep enough for seasonal stratification. All of the watershed of lagoon is located in the province of Istanbul where 26% is located in the urban area and 74% is located in the rural area. The lagoon had been subjected to high nutrient and organic matter loads from late 70s through three main streams and reached a hypertrophic state. This long-term study analyzes the pollution and the progressing recovery of the lagoon from its eutrophic state for more than a decade from the year 2006 up today (2019) and proposes possible restoration techniques to accelerate recovery of the lake from its hypertrophic state