Riverbank Filtration – A Potential Water Source Exploitation for the Red River Delta Region

Riverbank filtration technology has been widely applied worldwide because of its high-capacitycollection and good water quality throughout natural purification processes. Infiltration water can beextracted from Holocene (qh) layer or the Pleistocene deep layer (qp), replenished with water from theriver through hydrogeological windows. Hydrodynamic and isotopic signatures were employed todetermine water seepage capacity. The results show that infiltrated water is found in the sand layers alongthe rivers. However, the seepage rate shows a heterogeneously spatial variation ranging from 30 m3/d inthe Dinh Dao river to 33,600 m3/d. Km along the shoreline in the Red River (RRD). Also, the exploitationcapacity of seepage water differs widely in order of large (> 3,000 m3/d), medium (1,000-3,000 m3/d),small (500-1,000 m3/d), and very small capacity (200-500 m3/d). This study indicated that RRD couldapply riverbank filtration techniques to overcome freshwater scarcity in the delta due to increasing surfacepollution and discharge reduction.

Solid, Liquid and Gas Waste Management includes Handling of Impacts

The discussion talked about handling the environment and society from solid, liquid, and gas waste management. In this paper there are several methods that can be used to treat wastewater, including, Dilution (disposal by dilution). Wastewater is discharged into rivers, lakes or the sea to dilute. In this way the wastewater will undergo natural purification. However, this method can contaminate surface water with pathogenic bacteria, worm larvae and eggs, and other germs in the wastewater. If only this method is applicable, the following conditions must be met, River or lake water may not be used for other purposes.

Oxyresveratrol promotes biofilm formation, cell attachment and aggregation of Streptococcus gordonii in the presence of sucrose

ABSTRACT Streptococcus gordonii is a commensal colonizer of oral cavity that initiates the formation of dental plaque. Oxyresveratrol is a natural purification from plants with antibacterial effects on various oral bacteria including Streptococcus mutans. The aim of this study was to investigate the effects of oxyresveratrol on S. gordonii. The basic viability, biofilm formation and cell aggregation of S. gordonii treated with oxyresveratrol were investigated. Oxyresveratrol dose-dependently inhibited the growth of S. gordonii in the absence of sucrose. However, in the presence of sucrose, it promoted biofilm formation under MIC. Both the biofilm formation and extracellular polysaccharides synthesis reached the maximum level at ½ MIC (250 μg/mL) oxyresveratrol. The gene expressions of abpA, abpB, scaA, gtfG, hsa, cshA, cshB, ccpA, srtA and sspB were upregulated when treated with 62.5 and 125 μg/mL oxyresveratrol. A total eight of the ten genes were significantly upregulated at 250 μg/mL oxyresveratrol except abpB and sspB, which were downregulated at 250 μg/mL without significance. In conclusion, oxyresveratrol has dual-effects on S. gordonii. Considering its specific biofilm suppressive effect on S. mutans, it might be a candidate for bacterial interspecies modulator applied in caries prevention.

Deviation Degree between Ideal and Real Domain Transition Probabilities in Resource Circulation Considering the Production Synchronization Ratio

The ideal state for achieving smooth resource circulation on Earth is achieved when the intake, expulsion, and natural purification rates (three-element) are equal. In this research, we propose the four-element deviation degree, which combines the three-element deviation degree with the synchronization deviation degree, by considering the deviation degree of the synchronization between production and sales in corporate activities. We use a domain transition probability model for resource circulation, and based on this model, we investigate the three-element deviation degree to evaluate the deviation degrees of these three elements in ideal and real situations quantitatively. Further, we conduct a quantitative discussion of the gap between the ideal and real situations in the four domain transitions, including corporate activities, by considering the four-element model. We considered simple numerical examples of the current state (t = 0) vector (initial state vector) and the domain transition probability matrix and simulated the resource circulation. Each simulation indicated the effect of slow natural purification from the waste domain to the resource domain in the natural space. Unlike previous studies based on input-output analyses, the proposed model, which can describe the circulation of natural and social spaces, considers the time course of natural purification. We believe that the proposed model is more realistic than the previous ones and is more suitable to describe the real society.

A preliminary pollution appraisal of western backwater at Karachi Coastal area

This study aims at preliminary analysis of pollution profile of western backwater. The site is very important from the ecological perspective. The mangrove ecosystem of the study area is of prime significance, whilst the study area is receiving heavy pollution load from Lyari River. The water samples were collected from the pre-designated locations and analyzed for physical and biochemical characteristics. The BOD and COD concentrations of the samples were extremely higher from the environmental and ecological viewpoint. The heavy inorganic and organic load is coming from the domestic and industrial effluents coming from Lyari River. Oil and grease concentrations were also extremely higher in all these sites indicating the hampering of natural purification system of water. The concentration of phenol also indicates the emptying of industrial effluent at the Lyari River outfall. The heavy influx of the nutrients in the form of nitrogen and phosphate represents the problem of eutrophication at the study area. Out of all 7 sites, L-7 was most polluted as it was closed to the Lyari River outfall. The extent of pollution is at the following order L-7 > L-5 > L-6 > L-4 > L-3 > L-2 > L-1.

Irrigation based leachate treatment

In southern Sweden, several irrigation based on site treatment has been established the lastyears. Briefly they consist of a pound to storing leachate water with pre-treatment and asystem what irrigate vegetation. It could be areas of willow plantations designated for energy purposes or grass or as in same cases spontaneous vegetation.The use of willow have been studied since 1992. These tests have clearly shown that recycling of municipal wastewater in Salix plantations, can replace a large part of the conventional wastewater treatment, due to natural purification processes in the soil/plant system.During the last few years, several full-scale treatment plants based on the soil/plant systemhave been set up to treat leachate water from municipal solid waste (MSW) landfills.One other way to reduce leachate water is to use transpiration. On dry days leachate ispumping and irrigated ideal on top of landfills inside the leachate collection system.Rosenqvist Mek.Verkstad has developed the irrigation system "RWIS" for distribution ofwaste and leachate water into the plantation. The irrigation system has to be able to withstand trying conditions, without major maintenance in between harvests.