The Konya Closed Basin (KCB) in Türkiye plays a key role in agricultural production and freshwater supply. However, the basin is impacted by humanly derived nitrogenous compounds and toxic metals. Keeping the water quality at a potable level in the basin is compulsory. This study was part of a project yielding monitoring of water quality in KCB in accordance with the Water Framework Directive (2000/60/EC). Eleven stations, except Beyşehir Lake and Mamasın Dam, were sampled for the first time for freshwater molluscs. Community structure indexes and multivariate statistical analyses were applied to determine the microhabitats of gastropods and their responses to environmental changes. The structure and distribution of gastropod assemblages differed depending on total phosphate, total nitrogen, dissolved oxygen, and pH. This study revealed that most of the gastropods in KCB are relatively tolerant to biodegradable pollution. However, there is a strong observed decline in population size requiring intensive future monitoring; measures have to be taken to preserve the remaining populations. Two endemic species need an urgent action plan to protect their habitats: Theodoxus anatolicus of Çeltik Canal and Bithynia pseudemmericia of Beyşehir Lake; a re-assessment of their extinction risk according to the IUCN rules is needed (2022). The results of this study will be useful for comparison with future studies to document potential improvements or continued ecological regression in the quality of aquatic ecosystems in the watershed.

The distribution of Rotifers in 18 dam lakes and natural lakes of Inner Anatolia, the Western Black Sea Region, the Mediterranean Region and Eastern Anatolia was studied between 1999 and 2004. Ninety rotifer species were found, of which six (Brachionus forficula, Dicranophorus epicharis, Epiphanes macrourus, Lecane rhytida, Lecane obtusa, Testudinella parva) are new to the Turkish fauna.

Observing the changes of zooplanktonic organisms over the years can give us consistent information about the limnological conditions of the present and future. Our aim in this study was to determine current conditions of zooplankton fauna of Abant Lake, which was studied seasonally, and could provide resources for future studies. The samples of zooplankton were collected horizontally and vertically from Abant Lake seasonally, between 2015 -2016 from seven stations. At the end of the study, a total of forty-nine zooplankton species were identified. Of these, 33 belonged to Rotifera, 14 to Cladocera and 2 to Copepoda. In addition, twelve species of Rotifera, and six species of Cladocera were found as new records for the Abant Lake.

Freshwater ecosystems are vital for providing essential services such as water supply and food production. However, increasing human demands have led to significant environmental degradation in these ecosystems. Türkiye, recognized as a global biodiversity hotspot, faces numerous threats from altered flow regimes, land-use changes, pollution, and invasive species. Despite these challenges, Türkiye’s diverse environments support a rich assemblage of zooplankton, with over 662 identified taxa spanning rotifers, cladocerans, and copepods. This study conducted a bibliometric analysis of zooplankton research at both global and national (Türkiye) levels to understand research trends, identify knowledge gaps, and highlight key areas of focus. Globally, stress factors and climate change dominate the research agenda, whereas, in Türkiye, topics such as abundance, diversity, water quality, and bioindicators have gained attention, albeit with relatively low frequency. Since 2013, these themes have shaped the direction of Turkish zooplankton research. The findings of this study emphasize the need for targeted research to better understand the impacts of environmental stressors on zooplankton communities in Türkiye, while also contributing to the global discourse on ecosystem functionality. By using zooplankton as key biotic indicators, this research offers insights into ecosystem health, providing critical information for future conservation and management efforts.

This study revealed the current metal(loid) status of the Mavi Dam Lake, which is one of the important wetlands for Ankara, established the accumulation relations between metal(loid)s separately, and seek an answer to the question of whether the current metal(loid)s status poses a risk of public health. The amounts of 13 metal(loid)s were determined. Sediment quality guidelines were calculated to understand the ecological risk of metal(loid)s in the sediment and the results were compared with limit values. It was determined that Ni constitutes 51.28% of the total toxic effects of metals detected in the sediment. Ni and Cr revealed a strong correlation between cluster and correlation analyses and were involved in the same factor in the principal component analysis. Additionally, it was determined that As, Cd, Co, Cr, and Ni may pose carcinogenic risks in terms of public health by contact with the lake or ingestion. In conclusion, it was revealed that the lake being studied should be regularly monitored for all metal(loid)s, especially Ni, and Cr.