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The current study was performed with an aim to investigate the performance of ecological revetments implemented on the bank of the Cuatien River in Vinh city, Vietnam. Based on the ecological, topographical, and hydrological conditions of the Cuatien River, the gabion and riprap models were introduced to investigate the effect of ecological revetment on the slope stability and ecological restoration characteristics. The effect of prevailing climatic indicators, such as temperature, precipitation, sunlight hours, and humidity were investigated to ascertain the characteristics of weather conditions on the subtropical area. On the surface soil layer of the gabion and riprap, the nutrient indicators of soil organic matter (SOM) and available nitrogen (AN) increased in the spring, summer, and winter, but decreased in autumn, and available phosphorus (AP) did not show an obvious change in the four seasons. The biomass growth rate of Vetiver grass on the gabion and riprap revetments was found to be the highest during the summer, at 15.11 and 17.32 g/month, respectively. The root system of Vetiver and other native plants could increase the cohesion of soil. After 6 and 12 months, the shear strength of the soil behind the gabion revetment increased by 59.6% and 162.9%, while the shear strength of the soil under the riprap also increased by 115.6% and 239.1%, respectively. The results also indicated that the gabion and riprap revetments could improve the river water purification effect and increase the ecological diversity in the region. In the current study, 26 floral and 9 faunal species were detected in the riprap revetment, whereas 14 floral and 5 faunal species were detected in the gabion revetment, respectively. Through high sequencing technology, the number of bacterial species in the present study was found to be 198, 332, and 351 in the water, gabion, and riprap samples, respectively. Full article

To improve aquatic environmental quality and maintain channel stability against soil erosion, ecological bank slope revetments for surface water bodies were developed using a combination of prefabricated porous concrete spheres and vegetation methods, and a model set-up consisting of two equal-sized ditches with different types of bank slope revetments was constructed to evaluate the purification effects of ecological and hard revetments on water quality. The slope of one ditch was embanked with ecological revetments as an experimental treatment, while the other was embanked with hard revetments as a control. Pollutant removal from the ecological bank revetment ditch was significantly better in terms of the overall removal efficiencies of the chemical oxygen demand of manganese (COD_Mn), ammonia, total nitrogen (TN), and total phosphorus (TP), with two- to four-fold greater removal compared with that from hard slope revetments under the same operational conditions. Nutrient pollutants, including ammonia, TN, and TP had higher removal efficiencies than that for COD_Mn in both experimental ditches. The dependence of the first-order rate constant (k₂₀) and temperature coefficient () obtained from the Arrhenius equation indicated that the removal efficiencies for ammonia, TN, and TP were higher with greater rate constants (k₂₀) in the experimental ditch. In the ecological revetment ditch, the k₂₀ values for COD_Mn, ammonia, TN, and TP were 0.054, 0.378, 0.222, and 0.266 respectively, around three-fold the values observed in the hard revetment ditch, but there was no obvious difference in values between the two ditches. The k₂₀ values of TN and TP in both ditches showed significant positive correlations with seasonal shifts, as the removal of nutrient pollutants is highly sensitive to water temperatures. Full article