Xin Ma , Yi Li , Lihua Niu , Hans-Peter Grossart , Jiahui Shang , Jinhai Zheng , Jianming Wu
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引用次数: 0
Abstract
Artificial cut-off of natural tidal meanders for flood control has substantially altered microbial communities and their role in nutrient cycling, yet the lack of comprehensive investigations into these specific anthropogenic impacts introduces greater uncertainty regarding the resultant water quality of nutrient-enriched estuaries. Here, we investigated how planktonic multitrophic microbiota and their mediated nutrient cycling respond to artificial meander cut-off using the environmental DNA (eDNA) approach. Results showed that despite the decline in α diversity of multitrophic microbiota, the nutrient cycling potential of the water column was enhanced 2.91-fold in the straight tidal channel. The artificial cut-off restructured the microbial food web, with trophic transfer efficiency from basal species to protozoa increasing. Salinity was identified to be the key environmental driver, mitigating the negative impact of decreased biodiversity on estuarine nutrient cycling potential by intensifying protozoan predation on heterotrophic bacteria (top-down forces). Additionally, salinity further enhanced environmental selection (bottom-up forces), reducing heterotrophic bacterial diversity while promoting the proliferation of functional microbial taxa, such as Comamonadaceae, Chitinophagaceae, and Rhodocyclaceae. This study offers novel insights into nutrient cycling in artificial straight tidal channels and provides critical foundations for optimizing restoration and management strategies in anthropogenically modified tidal river.
期刊介绍:
Water Research, along with its open access companion journal Water Research X, serves as a platform for publishing original research papers covering various aspects of the science and technology related to the anthropogenic water cycle, water quality, and its management worldwide. The audience targeted by the journal comprises biologists, chemical engineers, chemists, civil engineers, environmental engineers, limnologists, and microbiologists. The scope of the journal include:
•Treatment processes for water and wastewaters (municipal, agricultural, industrial, and on-site treatment), including resource recovery and residuals management;
•Urban hydrology including sewer systems, stormwater management, and green infrastructure;
•Drinking water treatment and distribution;
•Potable and non-potable water reuse;
•Sanitation, public health, and risk assessment;
•Anaerobic digestion, solid and hazardous waste management, including source characterization and the effects and control of leachates and gaseous emissions;
•Contaminants (chemical, microbial, anthropogenic particles such as nanoparticles or microplastics) and related water quality sensing, monitoring, fate, and assessment;
•Anthropogenic impacts on inland, tidal, coastal and urban waters, focusing on surface and ground waters, and point and non-point sources of pollution;
•Environmental restoration, linked to surface water, groundwater and groundwater remediation;
•Analysis of the interfaces between sediments and water, and between water and atmosphere, focusing specifically on anthropogenic impacts;
•Mathematical modelling, systems analysis, machine learning, and beneficial use of big data related to the anthropogenic water cycle;
•Socio-economic, policy, and regulations studies.