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出版Google Book Publishers
主題Technology & Engineering / Environmental / Water SupplyTechnology & Engineering / Environmental / Pollution Control
URLhttp://books.google.com.hk/books?id=-N90EAAAQBAJ&hl=&source=gbs_api
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註釋Water and land are precious natural resources for the agricultural activities, which are prerequisite for any civilization. Rapid industrialization and urbanization exploit and severely pollute these resources. The organic and inorganic pollutants generate an unfavourable environment for the survival of aquatic flora and fauna by affecting the aquatic ecosystems. The increasing urbanization, industrial revolution, advancement of technologies, etc. are the reasons for increased pollution level. Pollution is the discharge of the contaminating substances that have adverse effects on the environment. It reduces the quality of the environment by contaminating it with impurities. Smoke and dust particles pollute the air, solid waste pollutes the land, and in the same way industrial discharge, municipal sewage, and domestic wastewater pollute the water resources (streams, lakes, oceans, groundwater). Pollutants, thereby, present in wastewater, take the entry into food chain and food web. Heavy metals are outlined as substances with comparatively high density, high atomic weights, and high atomic numbers. They naturally occur within the earth’s crust but presently due to several manmade activities, they pool-up at certain places and hamper the natural constitution and function of natural resources they invade. The natural sources of heavy metal intrusion are weathering of minerals, volcanic eruptions, overexploitation of underground resources, etc., which cause heavy metals of underlying rocks to leach into the groundwater, whereas man-made sources are smelting, mining, industries, sludge selling, agricultural use of serious metals in fertilizers and pesticides and many more. Some of the heavy metals like Lead, Mercury, Arsenic, and Chromium are one of the culprits for global warming and destroying the atmospheric ozone with atmospheric methane, nitrous oxide, and sulphur dioxide. Environmental contamination by heavy metals is a serious problem throughout the world. The addition of toxic heavy metals in the ecosystem may lead to its bioaccumulation, geo-accumulation, and biomagnification. The heavy metals can be removed by using some common conventional treatment processes. Physicochemical removal processes such as adsorption, ion exchange, membrane filtration, reverse osmosis etc. are used to remove heavy metals. Biological treatments using microorganisms include methods such as activated sludge, trickling filters, stabilization ponds etc. Biosorption and phytoremediation are promising, low cost, eco-friendly best solution for removal of heavy metals. The phytoremediation applications can be classified based on contaminant fate: degradation, extraction, containment or combination of these. Phytoremediation applications can be classified based on mechanisms involved. Such mechanisms include extraction of contaminant from soil or groundwater; concentration of contaminants in plant tissue, degradation of contaminants by various biotic and abiotic processes; volatilization or transpiration of volatile contaminants from plants into air, immobilization of contaminants in root zone etc. The present book Chemical Nature of Groundwater and its Bioremediation focuses on preliminary screening of aquatic macrophytes having phytoremediation potential, selection of two specific hyperaccumulator species for phytoremediation, screening of heavy metals accumulation potential and biochemical constituents of selected plant species involving heavy metal treatment, assessing heavy metal accumulation potential, physio-chemical and phytochemical parameters with a treatment of electroplating industry effluent, measuring the phytoremediation efficiency of two selected plant species by in situ experiments, assessing the physico-chemical characteristics of contaminated water treated with two selected plant species, and heavy metal accumulation in biomass by both the species.