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Time-space Varieties Of Heavy Metals In Water Body Of The Three Gorges Reservoir After The Water Level Reached 135 Meters

Posted on:2006-03-07Degree:MasterType:Thesis
Country:ChinaCandidate:L L LiFull Text:PDF
GTID:2121360185475225Subject:Environmental Engineering
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When the three gorge project run, with the rapid development of economy, the peple in town and the quantity of shippings increased. If no controlled, the contaminative loads will increase. Simultaneity, with the three gorge reservoir being founded, hydraulics conditiones of the Yangtes Rive will change, the surface widened, the depth deepened, the velocity of flow decreased, the ability of self-decontaminate weakened.; the bank contaminative zones may lengthen and widen, the area may increase, the concentration of pollutants may increase. Heavy metals occurred a series of reactiones in different conditiones of acid and alkali and redox. It may create dissolvable compounds transferring along the current, or thawless compounds depositted in the water. For the heavy metal presenced in the form of iones, it was easy to adsorb on the suspension substance and colloid. In different acid and alkali conditiones, it come into the water again with the agglomeration or dissipation of the colloid.It studied on the heavy metals of upriver, backriver, reservoir areas contrastively before and after the water level reached 135 meters. As a result, the status of heavy metal pollutions was obtained before and after the water level reached 135 meters, the basic datas were also offerred when water level reaches to 156 and 175 meters. Simultaneity, based on the heavy metal pollution status and health risk assessment, the preferential controlled pollutants can also be made sure. It can offer scientific accordings and primary decision-makings to administration of environmental health risk.Zhu tuo, Cuntan(upriver area), Qingxichang(backriver area), Wanzhou(reservoir area) were representative to analyse the horizontal and vertical distribution of the 4 heavy metals. The result indicated that the concentration of total Pb had augment trend after the water level reached 135 meters; the concentration of dissolvable Pb had the augment trend before the water level reached 135 meters, and had depressed trend after the water level reached 135 meters. Total Cu had augment trend after the water level reached 135 meters . Along the current direction, total Cu had augment trendand before and after the water level reached 135 meters; except Zhu tuo, dissolvable Cu had augment trend in the other monitoring sites after the water level reached 135 meters. Total Cd had no significant differences in different monitoring sites and had augment trend after the water level reached 135 meters; dissolvable Cd had no significant differences before and after the water level reached 135 meters in different monitoring sites. The bulk of total Hg and dissolvable Hg were not checked up and had no significant differences before and after the water level reached 135 meters.Before and after the water level reached 135 meters, there was no significant differences in the upper-lever, middle-level and under-level as a whole. Before the water level reached 135 meters, the variation coefficients of total Cu and dissolvable Cu were 15.6% and 15.3%, and the others were less...
Keywords/Search Tags:the Three Gorges Reservoir, 135 meters water level, Water body, Heavy metals
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