Comparative Study on Influences of Bank Slope Ecological Revetments on Water Quality Purification Pretreating Low-Polluted Waters

Abstract

Abstract: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 (k 20 ) and temperature coefficient (θ) obtained from the Arrhenius equation indicated that the removal efficiencies for ammonia, TN, and TP were higher with greater rate constants (k 20 ) in the experimental ditch. In the ecological revetment ditch, the k 20 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 θ values between the two ditches. The k 20 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.

Biostimulation of Domestic Water Contaminated by a Mixture of Hydrocarbons

“…Figure 3 shows the analysis of the response of the microbiota in domestic water impacted by WMO biostimulated with mineral solutions 1 and 2 in the mineralization of the WMO, where a statistical difference was observed in the nutritional induction of the heterotrophic microbiota with the. mineral solution1 (15,20,21), in the oxidation of the WMO, with a CO 2 value of 5.7 mM /mL, in contrast to the microbiota of domestic water impacted by the WMO without biostimulation by the concentration of the basic components of the mineral solution 2 that did not allow the WMO oxidation with numerical value (19,22,23), non-statistical difference compared to the CO 2 concentration by the microbiota of domestic water impacted by WMO, without biostimulation with the mineral solution used as negative control (23). The positive effect of biostimulation on the heterotrophic aerobic microbiota of WMO-impacted domestic water to oxidize it (11,12) were consistent with mass-coupled gas chromatography analysis (22,23) that specifically demonstrated the aliphatic types that were removed (5).…”

“…mineral solution1 (15,20,21), in the oxidation of the WMO, with a CO 2 value of 5.7 mM /mL, in contrast to the microbiota of domestic water impacted by the WMO without biostimulation by the concentration of the basic components of the mineral solution 2 that did not allow the WMO oxidation with numerical value (19,22,23), non-statistical difference compared to the CO 2 concentration by the microbiota of domestic water impacted by WMO, without biostimulation with the mineral solution used as negative control (23). The positive effect of biostimulation on the heterotrophic aerobic microbiota of WMO-impacted domestic water to oxidize it (11,12) were consistent with mass-coupled gas chromatography analysis (22,23) that specifically demonstrated the aliphatic types that were removed (5). In comparison with the domestic water impacted by WMO non biostimulated that supports the concentration of essential minerals to induce microbial consortia of domestic water for mineralization of the aliphatics of the WMO with mineral solution 1 (13,14,15).…”

Objectives and Indexes for Implementation of Sponge Cities—A Case Study of Changzhou City, China

“…The relationship between the annual runoff control rate and the design rainfall is illustrated in Table 1 and Figure 6. ratio, designed rainfall and rainfall frequency, the rainfall characteristics of Changzhou city and the rainfall data of the past 30 years were analyzed to determine the value of annual runoff control ratio [42]. The relationship between the annual runoff control ratio and the design rainfall is illustrated in Table 1 and Figure 6.…”

“…These factors may lead to water quality deterioration. Therefore, the recovery of ecological function of river banks and lake shores is one of the effective water quality improvement measures [42].…”

Effect of the Matrix Dam in the Paddy Field Drainage Ditch on Water Purification Based on the Physical Model Test

“…It can also be combined with other technologies, and the removal rate of total nitrogen and total phosphorus can reach 71.4% and 51.0% [10][11][12][13][14][15]. Ecological revetment technology in water quality treatment projects has also been widely recognized [16][17][18][19][20][21]. Nevertheless, the applications of these techniques in removing pollutants from the drainage water of the paddy field are limited.…”