Bacterial Communities and Soil Functionality in Artificially Remediated
Vegetation of the Three Gorges Reservoir Zone
Abstract
Riparian zones maintain biodiversity, cyclic nutrients, and regulate
water quality. However, anthropogenic disturbances such as dam
construction and climate variability threaten their stability. This
study explored the seasonal and vegetation-specific dynamics of soil
properties and microbial communities in riparian zones dominated by
artificially remediated plants (ARPs). We studied these ARPs (
Cynodon dactylon (CD), Hemarthria altissima (HA),
Salix matsudana (SM), and Taxodium distichum (TD)) across
spring (T1), summer (T2), and autumn (T3). Analysis of 360 soil samples
produced high-quality sequences that revealed insights into microbial
diversity. Principal component analysis showed that organic matter,
ammonium nitrogen, and total nitrogen were the main contributors to soil
property variance. They explained 53.68% (T1), 51.52% (T2), and
56.37% (T3) of the variance (p < 0.01). The correlation
analysis revealed a positive correlation between soil pH and
Nitrospirae (r = 0.603) and Proteobacteria (r = 0.558).
Enzyme activity varied by season; acid phosphatase was highest in T3,
and invertase was highest in T1. This study made functional predictions
and identified pathways relevant to metabolism, genetic information
processing, and environmental signal transduction. Both T3 via TD and T3
via CD showed seasonal shifts in their metabolic pathways. These shifts
included an increase in carbohydrate metabolism in T3 via TD and an
increase in amino acid metabolism in T3 via CD. Analysis of microbial
diversity identified 68 bacterial phyla, with Proteobacteria and
Acidobacteria being the dominant taxa. Our results show that ARPs
improve microbe health, nutrient cycling, and the ecosystem as a whole.
This has implications for restoring riparian ecosystems in places where
the environment has changed.