Environmental Factors Drive Periphytic Algal Community Assembly in the Largest Long-Distance Water Diversion Channel

Abstract

Periphytic algae exist widely in different waters. However, little is known about periphytic algae in long-distance water diversion channels across watersheds. We investigated the periphytic algae and the environmental factors at twenty sampling sites in the middle route of the South-to-North Water Diversion Project (MRP). The dominant species were Desmodesmus intermedius (Hegewald), Calothrix thermalis (Bornet & Flahault), Calothrix parietina (Bornet & Flahault) and Leptolyngbya benthonica (Anagnostidis) (dominance > 0.02) as measured in a whole year. Habitat heterogeneity in the MRP led to lower spatial heterogeneity and higher temporal heterogeneity of the periphytic algal community. Stochastic processes are the major process in periphytic community assembly. In deterministic processes, homogeneous selection had the major role in structuring the periphytic community, whereas the role of heterogeneous selection was less significant. In stochastic processes, dispersal limitations had the major role in structuring the periphytic community, whereas the role of homogenizing dispersal and drift were less significant. The variation in total nitrogen and total phosphorus promoted more stochastic processes (−1.96 < βNTI < 1.96). The variations in water temperature and water velocity promoted more heterogeneous selection (βNTI > 1.96). In integrating all of this empirical evidence, we explore the role of environmental factors in the action of ecological processes shaping thecommunity assembly of the periphytic algal community.

Environmental Drivers and Aquatic Ecosystem Assessment of Periphytic Algae at Inflow Rivers in Six Lakes over the Yangtze River Basin

“…Chlorophyta, Bacillariophyta, and Cyanobacteria were the most common periphytic algae in Poyanghu Lake [11]. Bacillariophyta was likewise found to be the most prevalent species in the Danjiangkou Reservoir and its associated water channel [10]. The dominant phyla of this study are Bacillariophyta and Cyanobacteria, which is consistent with prior findings.…”

“…Periphytic algae in the Danjiangkou inflow river was dominated by Cyanobacteria, Bacillariophyta and Chlorophyta; the enriched species in the genus level are Navicula and Achnanthidium, which are both cosmopolitan in rivers [10]. TUB, TP and COD Mn are the most driving environmental factors in the Danjiangkou inflow river.…”

“…Pollution-tolerant taxa, such as bacillariophytes Navicula, dominated the structure of periphytic algae in Dianchi Lake, and TN, NH 4 -N + , and TP were significant aquatic environmental factors impacting the community composition of periphytic algae [8]. Seasonal fluctuation had a substantial impact on environmental parameters at the Danjiangkou Reservoir and its related water diversion channel, water temperature and nutrient concentration were the key factors determining the structure of the periphytic algae community [9], and the environmental factors plays an important role in shaping the periphytic algal community assembly in the water diversion channel based on marker gene analysis [10]. Different water levels in Poyang Lake resulted in environmental variety, resulting in varied habitats for periphytic algae [11].…”

Differences in density: taxonomic but not functional diversity in seaweed microbiomes affected by an earthquake

“…However, drift and dispersal limitation were greater contributors to microbiome structure in low density populations than for high density populations. Independence of microbiome successional trajectories is anticipated to increase the influence of drift, because interactions between hosts promote microbial dispersal and lessen the probability that a microbial taxon is lost (50,54,55). For the same reason, we would also anticipate dispersal limitation to be a greater factor in low density populations, as frequency of physical interactions may shape the microbiome of D. antarctica as they do in other species (56).…”

High‐latitude invasion and environmental adaptability of the freshwater mussel Limnopernafortunei in Beijing, China

“…Since opening in December 2014, the middle route of the SNWTP (M‐SNWTP) has transferred more than 60 billion m 3 of water to over 20 cities, effectively alleviating water shortages and stabilizing groundwater levels in the recipient areas (Long et al, 2020). However, the scheme inevitably provides some exotic species with a rapid way to invade northern waters (Zhan et al, 2015; Zhang et al, 2023) and, thus, threatens the local aquatic biota (e.g., macroinvertebrates and phytoplankton; Zhang et al, 2021; Zhu et al, 2022). L. fortunei colonization of structures along the middle and north sections of the M‐SNWTP (e.g., Henan and Hebei provinces), with adult attachment density occasionally exceeding 10,000 ind m −2 , has been reported (Zhao et al, 2019).…”