Environmental preservation and remediation techniques in costal waters

为了评价封闭水域的环境保护和修复技术，收集了清水港和真那若湖的海水和湖水、悬浮物、沉降颗粒和沉积物。从河流中排放的悬浮固体和在港口和湖泊中产生的生物颗粒导致透明度降低和化学需氧量增加。微量金属，如锰、钴和铅，在悬浮物中高度集中。结果表明，这些悬浮粒子与生物源粒子一样，能有效地从海水和湖水中积累金属。微量金属颗粒沉积后，在厌氧条件下再生到海水和湖水中。这一过程对水和沉积物中化学物质的积累起着重要作用，特别是在封闭海域。结果表明，测得的重金属浓度较高。沉积物样品中的铜和锌浓度高于加拿大沉积物质量准则规定的海洋沉积物的可能影响水平（PEL）。获得的高浓度可能是由于腐殖质产生的高有机含量。有机物的分离可能是一种有用的疏浚材料修复技术。试验考察了炼钢渣在若干海域改善海底沉积物的适用性。实验结果表明，石质炼钢渣控制了硫化物的发生，该材料可作为水下路基材料，可作为藻类和底栖生物的基质。还发现，炼钢渣颗粒可以作为有效的基质，为附着的藻类提供营养。

To assess the environmental preservation and remediation techniques of an enclosed water areas, seawater and lake water, suspended solids, settling particles and sediment were collected from Shimizu Port and Lake Sanaru. Suspended solids discharged from rivers and the biological particles produced in the port and lake caused a reduction in transparency and an increase in chemical oxygen demand. Trace metals, such as Mn, Co, and Pb, were highly concentrated in suspended solids. The results showed that these suspended particles could accumulate metals from seawater and lake water as effectively as biogenic particles. After particle deposition, trace metals are regenerated into seawater and lake water under anaerobic conditions. This process plays an important role in the accumulation of chemicals in water and sediments, especially in enclosed sea areas. The results showed that the concentrations of the heavy metals measured were relatively high. The concentrations of copper and zinc in the sediment samples were higher than the probable effect levels (PEL) of marine sediments provided by the Canadian Sediment Quality Guidelines. The high concentrations obtained were probably due to the high organic content resulting from humus.The separation of organic matter might be useful as a remediation technique for dredged materials.The applicability of steelmaking slag was examined experimentally to improve the bottom sediments in several sea areas. The experimental results showed that stone-shaped steelmaking slag controlled the occurrence of sulfide, and that the materials were available as a submerged embankment material, which can be used for a base of algae and benthonic organisms. It is also found that the particles of the steelmaking slag can be an effective base and can supply nutrients for attached algae.