Are global influences of cascade dams affecting river water temperature and fish ecology?

Abstract

Global warming is affecting animal populations worldwide, through chronic temperature increases and an increase in the frequency of extreme heatwave events. Reservoirs are essential for water security. All watersheds with reservoirs are impacted by their construction. These artificial ecosystems controlled by humans change considerably the natural terrestrial and aquatic ecosystem and systems and their biodiversity. The rapid increase in population growth, urbanization, and industrialization are accompanied by an increase in river discharges, which increases the total amount of pollutants. HMs contamination in aquatic environments, as well as the subsequent absorption of HMs into the food chain by aquatic creatures and people, endangers public health. Multiple uses of reservoirs promote benefits in terms of economic development, income, and employment. HMs in water can be ingested directly by aquatic species like fish and can also be ingested indirectly through the food chain; thus, it is much more important and required to conduct frequent monitoring of the aquatic environment. As a result, this review summarizes knowledge about the effects of cascade dams on river water temperature and increases on the stress physiology of fishes, and adaptation to climate change is also needed to produce more fish without global warming.

Analysis of Water Temperature Variations in the Yangtze River’s Upper and Middle Reaches in the Context of Cascade Hydropower Development

“…The global rise in river water temperature, driven by climate change and intensified human activities, poses a growing threat to the stability of freshwater ecosystems [10]. Therefore, understanding the characteristics and ecological responses of water temperature changes is considerable for maintaining the health of these ecosystems [11]. River thermal regimes are shaped by a complex interplay of meteorological, geomorphological, and hydrological factors [12][13][14].…”

The influence of reservoirs on water temperature in the downstream of Ipeľ

“…Considering the potential negative consequences of increasing water temperature, it is necessary to study the influence of these factors, which is supported by advanced machine learning techniques that can facilitate the analysis of the evolution of water temperature in open waterways. The study of water temperature in rivers and water reservoirs has received much attention in recent decades (Sleziak et al, 2023;Soomro et al, 2023;Varga et al, 2023;Varga and Velísková, 2021). This is mainly because of concerns about the effects of climate change and human intervention.…”

Phytoplankton community response to water physicochemical characteristics under seasonal variation at the Ubol Ratana Dam, Khon Kaen, Thailand

“…Water resources are vital for all living organisms, but only 0.3% of freshwater on Earth is usable (Kılıç, 2020). Freshwater is commonly stored in dams or reservoirs and serves various purposes in agriculture, industries, households, and ood regulation (Soomro et al 2023). Freshwater dams show variations in physicochemical characteristics based on hydrological cycles and water ow characteristics, which impact the diversity of organisms in freshwater ecosystems, including phytoplankton (Graco-Roza et al 2021).…”