How Does Extreme Drought Affect Phytoplankton Community Assembly in Aquatic Reserves? A Study from the Confluence of Poyang Lake and Yangtze River, China

Diversity, Journal Year: 2025, Volume and Issue: 17(4), P. 301 - 301

Published: April 21, 2025

Extreme drought events, intensified by climate change, critically threaten aquatic ecosystem stability restructuring phytoplankton communities. However, the mechanisms underlying drought-driven community assembly remain poorly understood. This study investigated impacts of extreme on dynamics in reserves Jiujiang City, China, a critical ecotone Yangtze River and Poyang Lake. Through multi-temporal sampling (2022–2023) across 12 sites, we integrated taxonomic, functional group, co-occurrence network analyses with environmental driver assessments. The results revealed that significantly reduced species diversity triggered shift from disturbance-adapted (e.g., MP group) to pollution-tolerant taxa W1 group). Deterministic processes dominated assembly, driven drought-induced filtering through water temperature, dissolved oxygen, nutrient fluctuations. Copper emerged as key stressor, correlating abundance Cryptophyta. Co-occurrence networks, cohesion, robustness exhibited heightened complexity under drought, emphasizing stress-induced mutualistic interactions. Our findings elucidate how reshapes communities via deterministic interactions, offering insights for managing ecosystems escalating climatic extremes.

Language: Английский

Study on the Effect of Water System Connection on the Improvement of Water Quality of Inner Lakes in Town—Taking Seven Lakes in Yangshuo Urban Area of Guilin as an Example

Water, Journal Year: 2025, Volume and Issue: 17(9), P. 1398 - 1398

Published: May 7, 2025

Urban lake degradation caused by intensive urbanization necessitates systematic solutions, with water connectivity being a crucial ecological restoration strategy. This study evaluates the two-year effects (2020–2022) of interventions on seven lakes in Yangshuo, Guilin, classified connectivity: multi-channel (Mc), single-channel (Sc), and non-connected (Nc). Regular monitoring physicochemical parameters microbial communities revealed significant patterns: connected exhibited superior quality improvement, trophic state downgrading (weak eutrophic → mesotrophic), but Sc-BQ was deteriorating. Seasonal variations showed wet season peaks pH, DO, CODMn, Chl-a, versus dry elevations NH3-N, NO3-N, TN, TP. Correlation analysis identified organic matter as primary driver eutrophication, TN strongly linked to indicating persistent domestic sewage contamination. Microbial community restructuring accompanied changes quality, abundance diversity OTUs decreased after restoration. Notably, Limnohabitans dominated Mc (31.82–35.1%), while Pleurocapsa prevailed (37.85%) Nc-LH under weak conditions. These findings demonstrate that effectively enhances hydrodynamic conditions pollutant dispersion, whereas inadequate exacerbates nutrient accumulation. The provides critical empirical evidence for optimizing urban management, emphasizing necessity multi-dimensional designs targeted control untreated inputs system rehabilitation projects.

Language: Английский