Meryem Beklioglu

Middle East Technical University | METU · Department of Biology

The relevance of considering environmental variability for understanding and predicting biological responses to environmental changes has resulted in a recent surge in variability‐focused ecological research. However, integration of findings that emerge across studies and identification of remaining knowledge gaps in aquatic ecosystems remain criti...

Zoosporic parasites (i.e. fungi and fungi-like aquatic microorganisms) constitute important drivers of natural populations, causing severe host mortality. Economic impacts of parasitic diseases are notable in the microalgae biotech industry, affecting production of food ingredients, biofuels, pharma- and nutraceuticals. While scientific research on...

Global warming and altered precipitation patterns are predicted to intensify the water loss in semi-arid and arid regions, and such regions in Turkey will be particularly affected. Moreover , water abstraction, not least for irrigation purposes, is expected to increase markedly, posing major threats to the water balance of the lakes and thus their...

The ubiquitous presence of microplastics (MP) in aquatic ecosystems can affect organisms and communities in multiple ways. While MP research on aquatic organisms has primarily focused on marine ecosystems and laboratory experiments, the community-level effects of MP in freshwaters, especially in lakes, are poorly understood. To examine the impact o...

The widespread salinisation of freshwater ecosystems poses a major threat to the biodiversity, functioning, and services that they provide. Human activities promote freshwater salinisation through multiple drivers (e.g., agriculture, resource extraction, urbanisation) that are amplified by climate change. Due to its complexity, we are still far fro...

Extreme precipitation is occurring with greater frequency and intensity as a result of climate change. Such events boost the transport of allochthonous organic matter (allo-OM) to freshwater ecosystems, yet little is known about the impacts on dissolved organic matter (DOM) quality and seston elemental stoichiometry, especially for lakes in warm cl...

To determine the drivers of phytoplankton biomass, we collected standardized morphometric, physical, and biological data in 230 lakes across the Mediterranean, Continental, and Boreal climatic zones of the European continent. Multilinear regression models tested on this snapshot of mostly eutrophic lakes (median total phosphorus [TP] = 0.06 and tot...

The Konya Closed Basin (KCB) in Turkey has a cold semiarid to warm Mediterranean climate and hosts the largest Turkish freshwater lake, Lake Beyşehir, and the iconic saline Lake Tuz. Using published as well as our own ground-truth and remote sensing data, we provide (1) a brief description of the paleoenvironmental changes in the KCB; followed by (...

Body size is an important trait of any organism, including phytoplankton, because it affects physiological and morphological performance, reproduction, population growth rate and competitive interactions. Understanding how interacting top-down and bottom-up factors influence phytoplankton cell size in different aquatic environments is still a chall...

Global changes (e.g., warming and population growth) affect nutrient loadings and temperatures , but global warming also results in more frequent extreme events, such as heat waves. Using data from the world's longest-running shallow lake experimental mesocosm facility, we studied the effects of different levels of nutrient loadings combined with v...

To reveal information about the responses of zooplankton to different DOC sources thereby improving the understanding of climate change effects on lake ecosystems

Phytoplankton usually responds directly and fast to environmental fluctuations, making them useful indicators of lake ecosystem changes caused by various stressors. Here, we examined the phytoplankton community composition before, during, and after a simulated 1-month heat wave in a mesocosm facility in Silkeborg, Denmark. The experiment was conduc...

Shallow lakes are globally the most numerous water bodies and are sensitive to external perturbations, including eutrophication and climate change, which threaten their functioning. Extreme events, such as heat waves (HWs), are expected to become more frequent with global warming. To elucidate the effects of nutrients, warming, and HWs on zooplankt...

The cover image is based on the Original Article Changes in functional composition and diversity of waterbirds: The roles of water level and submerged macrophytes, by İbrahim Kaan Özgencil https://doi.org/10.1111/fwb.13531.

Submerged macrophytes are of key importance for the structure and functioning of shallow lakes and can be decisive for maintaining them in a clear water state. The ongoing climate change affects the macrophytes through changes in temperature and precipitation, causing variations in nutrient load, water level and light availability. To investigate h...

Climate and land-use change drive a suite of stressors that shape ecosystems and interact to yield complex ecological responses, i.e. additive, antagonistic and synergistic effects. Currently we know little about the spatial scale relevant for the outcome of such interactions and about effect sizes. This knowledge gap needs to be filled to underpin...

• Water level and submerged macrophytes are critical players for the functioning of shallow lake ecosystems; understanding how waterbird communities respond to changes in both can have important implications for conservation and management. Here, we evaluated the effects of changes in water level and submerged macrophyte status on wintering waterbi...

Climate warming threatens the structure and function of shallow lakes, not least those in the Mediterranean climate. We used a space-for-time substitution approach to assess the response of trophic and community structures as well as the richness and evenness of multiple trophic levels to temperature, hydrological, and nutrient constraints. We sele...

This Special Issue of Inland Waters (featuring 2 Special Sections spread across 2 issues) celebrates the contribution of Brian Moss to the science and management of freshwater ecosystems. Brian passed away in 2016, and since then much has been written about his life and achievements (Carvalho and Johnes 2016, Irvine and Barker 2016, Jeppesen and Jo...

Shallow lakes in the semi-arid climate zone of the Mediterranean are sensitive to drought due to the low annual precipitation and high evaporation. Changes in precipitation and temperature as projected by climate change scenarios will have an effect on the hydrology of these shallow lakes with secondary effects on nutrient dynamics and ecological s...

Fish community feeding and production rates may differ between lakes despite similar fish biomass levels because of differences in size structure and local temperature. Therefore, across-lake comparisons of the strength and direction of top-down and bottom-up fish–phytoplankton relationships should consider these factors. We used the metabolic theo...

The effect of microplastics (MP) exposure on the chironomid species Chironomus riparius Meigen, 1804 was investigated using the OECD sediment and water toxicity test. Chironomid larvae were exposed to an environmentally relevant low microplastics concentration (LC), a high microplastics concentration (HC) and a control (C). The LC was 0.007 g m-2 o...

Microplastics (MPs) are ubiquitous pollutants found in marine, freshwater, and terrestrial ecosystems, and MP pollution is a major environmental concern globally. Despite this, the impact of MPs on freshwater ecosystems is largely under-looked, with most research concentrating on marine systems and organisms. Owing to their small and wide range of...

This research was conducted in order to determine influence of mixture of microplastic particles (MP) on non-biting midges Chironomus spp. in laboratory and mesocosm setup.

There are infinite possible future scenarios reflecting the impacts of anthropogenic multiple stress on our planet. These impacts include changes in climate and land cover, to which aquatic ecosystems are especially vulnerable. To assess plausible developments of the future state of European surface waters, we considered two climate scenarios and t...

Lakes are vital components of the landscape that provide important ecosystem services. They act as sentinels of change, integrating information from atmospheric, terrestrial, and hydrological processes. To support sustainable lake management, lakes must be monitored to provide physical, chemical, and biological information. Monitoring strategies ra...

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 probl...

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 thei...

Invasion of non-native species is considered a major threat to global biodiversity. Here we present a comprehensive overview of the occurrence, richness and biomass contribution of non-native fish species in 1943 standing water bodies from 14 countries of the Western Palearctic, based on standardised fish catches by multi-mesh gillnetting. We expec...

Insight into how environmental change determines the production and distribution ofcyanobacterial toxins is necessary for risk assessment. Management guidelines currently focus onhepatotoxins (microcystins). Increasing attention is given to other classes, such as neurotoxins (e.g.,anatoxin-a) and cytotoxins (e.g., cylindrospermopsin) due to their p...

Water resources globally are affected by a complex mixture of stressors resulting from a range of drivers, including urban and agricultural land use, hydropower generation and climate change. Understanding how stressors interfere and impact upon ecological status and ecosystem services is essential for developing effective River Basin Management Pl...

Trochine et al. 2018 (Ecosystems) ESM

We analysed changes in the abundance, biomass and cell size of the microbial food web community (bacteria, heterotrophic nanoflagellates, ciliates) at contrasting nutrient concentrations and temperatures during a simulated heat wave. We used 24 mesocosms mimicking shallow lakes in which two nutrient levels (unenriched and enriched by adding nitroge...

To elucidate the specific and combined effects of bottom-up and top-down control on the microbial community in warm lakes, we sampled microbial community along with physical–chemical and biological variables and performed in situ food web experiments, in 14 Turkish shallow lakes with contrasting nutrient levels and predation pressures. Our field re...

Climate change and intense land use practices are the main threats to ecosystem structure and services of Mediterranean lakes. Therefore, it is essential to predict the future changes and develop mitigation measures to combat such pressures. In this study, Lake Beyşehir, the largest freshwater lake in the Mediterranean basin, was selected to study...

Body size is a key trait of an organism which determines the dynamics of predator–prey interactions. Most empirical studies on the individual size distribution of the aquatic community have focused on the variations in body size of a single trophic level as a response to certain environmental variables or biotic factors. Few studies, however, have...

Body size, coupled with abundance and taxonomy, may help to understand the mechanisms shaping community structure. Since the body size of fish is closely related to their trophic niche, size diversity (based on individual body size) of fish communities may capture intraspecific variations in fish trophic niches that are not detected by species dive...

Environmental factors such as increasing population, illumination period and hypoxia affect the phenotype of water fleas (Daphnia magna). Increasing hemoglobin amounts in water fleas’ that are subjected to hypoxia result in visible red pigmentation. According to literature, serotonin shows a reducing effect to methyl farnesoat (juvenile hormone) sy...

Lentic ecosystems act as sentinels of climate change, and evidence exists that their sensitivity to warming varies along a latitudinal gradient. We assessed the effects of nutrient and water level variability on zooplankton community composition, taxonomic diversity and size structure in different climate zones by running a standardised controlled...

D3.2 summary - river manuscripts: Manuscript 1 investigates the effects of a two months experimentally induced extreme low-flow scenario on the physical, biological, and functional characteristics in a macrophyte- rich lowland stream. A significant decline in the stream wetted habitat area, an increase in water temperature, and an increase in the a...

Eutrophication continues to be the most important problem preventing a favorable environmental state and detrimentally impacting the ecosystem services of lakes. The current study describes the results of analyses of 20 year monitoring data from two interconnected Anatolian lakes, Lakes Mogan and Eymir, receiving sewage effluents and undergoing res...

Here we provide the metadata for an overview on fish species presence/absence in 1943 Palearctic (Europe + Turkey) lakes and reservoirs. The data have been obtained by standardized multi-mesh gillnet fishing, primarily to fulfill the requirements of the European Water Framework Directive (WFD). The species list encompasses about 100 species, a few...

Summary D5.1-1 Part 1: Multi-stressors on surface water and effects on ecological statusHumans have increased the discharge of pollution, altered water flow regime and modified the morphology of rivers. All these actions have resulted in multiple pressures on freshwater ecosystems, undermining their biodiversity and ecological functioning. The Euro...

Climate change would augment water scarcity problems in Mediterranean catchments. • Future water level changes was simulated by linking SWAT model to ε-SVR model. • Climate change has a major impact on hydrology while effects of land use are minor. • Outflow management is critical to prevent Mediterranean lakes from diminishing. Inter-and intra-ann...

This deliverable investigates the impacts of changes in hydrology and nutrients on ecosystem structure and function of Mediterranean shallow lakes by using long term monitoring data of two lakes (Lakes Mogan and Eymir) and paleolimnological records of six lakes from Turkey. The first two papers are on Lakes Eymir and Mogan, which are two inter-conn...

Deliverable D4.1 is a synthesis report of the 16 regional case studies being undertaken in WP4 (Multi-stressors at the river basin scale. The report is composed of 3 parts. Part 1: Task 4.2 - Southern Basins region Part 1 reports the background to, and results and conclusions from Task 4.2 on four case studies from the Southern Basins region. The...

Losses of phosphorus (P) and nitrogen (N) have important influences on in-lake concentrations and nutrient loading to downstream ecosystems. We performed a series of mesocosm experiments along a latitudinal gradient from Sweden to Greece to investigate the factors influencing N and P loss under different climatic conditions. In six countries, a sta...

Cladocerans are increasingly used in palaeolimnological studies as their community composition is sensitive to both anthropogenic and natural forces in lakes. We present the results of a palaeolimnological investigation of three Turkish shallow lakes located in cold dry steppe and semi-dry Mediterranean climatic regions. The aim was to elucidate hi...

We conducted a fish survey in 40 lakes in western and central Turkey. Fifty species (one to eleven per lake) were recorded, including eighteen endemic and seven alien species. We investigated which local geo-climatic and other environmental variables shaped the fish assemblages. Altitude and temperature turned out to be the most important factors f...

We conducted a fish survey in 40 lakes in western and central Turkey. Fifty species (one to eleven per lake) were recorded, including eighteen endemic and seven alien species. We investigated which local geo-climatic and other environmental variables shaped the fish assemblages. Altitude and temperature turned out to be the most important factors f...

Part 1: This deliverable consists two manuscripts (MS) of lake time-series analysis in north-temperate region of Europe. 1st MS: ‘Is fish able to regulate filamentous blue-green dominated phytoplankton?’ submitted to ‘Hydrobiologia’, analyzes >40-year data on biota, fish catches, hydrochemistry, hydrology, and meteorological parameters in Lake Võrt...

Part 1: This deliverable consists two manuscripts (MS) of lake time-series analysis in north-temperate region of Europe. 1st MS ‘Is fish able to regulate filamentous blue-green dominated phytoplankton?’ submitted to ‘Hydrobiologia’, analyzes >40-year data on biota, fish catches, hydrochemistry, hydrology, and meteorological parameters in Lake Võrts...

Over the course of 78 days, 9 outdoor mesocosms, each with 1350 L capacity, were situated on a pontoon platform in the middle of a lake and exposed to 0 µg L−1 TiO2, 25 µg L−1 TiO2, or 250 µg L−1 TiO2 nanoparticles in the form of E171 TiO2 human food additive five times a week. Mesocosms were inoculated with sediment, phytoplankton, zooplankton, ma...

Losses of phosphorus (P) and nitrogen (N) have important influences on in-lake concentrations and nutrient loading to downstream ecosystems. We performed a series of mesocosm experiments along a latitudinal gradient from Sweden to Greece to investigate the factors influencing N and P loss under different climatic conditions. In six countries, a sta...

Losses of phosphorus (P) and nitrogen (N) have important influences on in-lake concentrations and nutrient loading to downstream ecosystems. We performed a series of mesocosm experiments along a latitudinal gradient from Sweden to Greece to investigate the factors influencing N and P loss under different climatic conditions. In six countries, a sta...

Periphyton communities play an important role in shallow lakes and are controlled by direct forces such as temperature, light, nutrients, and invertebrate grazing, but also indirectly by planktivorous fish predation. We performed a pan-European lake mesocosm experiment on periphyton colonization covering five countries along a north/south geographi...

Periphyton communities play an important role in shallow lakes and are controlled by direct forces such as temperature, light, nutrients, and invertebrate grazing, but also indirectly by planktivorous fish predation. We performed a pan-European lake mesocosm experiment on periphyton colonization covering five countries along a north/south geographi...

In warm lakes, fish aggregate within macrophytes, thereby weakening the role of these as a daytime refuge for zooplankton and altering the zooplankton size structure, predation pressure and water clarity. To elucidate the role of macrophytes as a refuge for zooplankton and their effect on zooplankton size distribution, we established three sets of...

1. To help improve our understanding of the nitrogen cycle in lakes, particularly in the context of climate change, we analysed total nitrogen (TN) and nitrate (NO � 3 -N) data from six mesocosm experiments (in Denmark, U.K., China and Turkey) covering different climatic regions. We assessed the effects of nitrogen (N) and phosphorus (P) loading, t...

According to the Intergovernmental Panel on Climate Change report released in September 2014, unprecedented changes in temperature and precipitation patterns have been recorded globally in recent decades and further change is predicted to occur in the near future, mainly as the result of human activity. In particular, projections show that the Medi...