Management and restoration of river ecosystem and resources

本合作研究的目的是评估饮用水资源在三卤甲烷形成潜力、诱变性、细胞毒性和合成有机化学品（如表面活性剂）方面的潜在风险，并开发一个基于洛东江流域用水、废水管理、农业和工业活动的水环境和水资源质量综合管理的计算机辅助系统。洛东江的水质在13个采样站进行了调查。本次调查测定的水质参数为水温、PH、溶解氧、BOD、COD、SS、TKN、NH4-N、NO2-N、NO3-N、DT-N、PO4-P、DT-P、叶绿素-a。洛东江和锦湖江的总BOD浓度分布范围分别为0.9 ~ 6.8 mg/l和1.0 ~ 48.2 mg/l。洛东江和锦湖江的叶绿素a浓度分别为1.423 ~ 15.36 mg/l和3.153 ~ 26.507 mg/l。在纳洞河和锦河中，LAS和ABS的浓度在0.1 ~ 8 ~ 1.5 mg/l之间，在污水处理厂原水中，LAS和ABS的浓度在1.0 ~ 3.2 mg/l之间，在处理后的水中，LAS和ABS的浓度在1.2 ~ 2.7 mg/l之间。5 d内LAS浓度下降超过70%，而9 d后TOC浓度仅下降约40%。卡厂供水系统和内当供水系统中THM的浓度分别约为10 ~ 20 mg/l和5 mg/l。还鉴定出了四氯化碳和氯丁。采用鼠伤寒沙门菌ta98或ta100菌株的Ames试验预孵育法对回收物质的致突变性进行了评价。回收的物质产生了大量的回变物，且回变物的数量与剂量有关，表明水中含有直接致突变物质。此外，在S9mix存在的情况下，回收的物质产生了大量的回复性物质，这表明从这些点回收的物质的代谢物应该是诱变的。一个样品在没有S9mix的情况下表现出弱的正诱变性，而在有S9mix的情况下则没有。事实表明，样品中含有间接诱变剂，但其活性应该很弱。洛洞和锦湖江的诱变物质应该是移框型的。计算机辅助系统可以估计流域的污染负荷，包括点源和非点源，并根据现有负荷和实施备选管理计划后的预期负荷预测水体质量。主要污染源为大邱市排放的夜壤和中水。此外，稻田、农田和森林也对农村地区作出了贡献。少

The purpose of this cooperative study is to assess potential risk of drinking water resources in terms of trihalomethane formation potential, mutagenecity, cytotoxicity and synthetic organic chemicals such as surfactants and to develop a computer-aided system for the comprehensive management of aquatic environment and quality of water resourcesbased on water use, wastewater management, agricultural and industrial activities in the Nakdong River basin.Water quality of the Nakdong river is surveyed at 13 sampling stations. The water parameters determined in this investigation were water temperature, PH, dissolved oxygen, BOD, COD, SS, TKN, NH4-N, NO2-N, NO3-N, DT-N, PO4-P, DT-P, Chlorophyll-a. The distribution of total BOD concentration in the Nakdong river and the Kumho river were ranged 0.9 to 6.8 and 1.0 to 48.2 mg/l, respectively. The concentration of chlorophyll-a in the Nakdong river was ranged from 1.423 to 15.36 mg/ and from 3.153 to 26.507 mg/l for the Kumho river.Total concentr … More ation of LAS and ABS in Nak Dong River and Kum Ho River were found at levels varying 0.1 8 to 1.5 mg/l and those in raw water in the sewage treatment plant was found at levels varying 1.0 to 3.2 mg/l, and that of treated water was found at levels varying 1.2 to 2.7 mg/l. Concentration of LAS decreased over 70 % within 5 days, whereas concentration of TOC decreased only about 40 % after 9 days. The concentration of THM in Kachang and Nae-Dang water supply system were about 10-20 mg/l and 5 mg/l, respectively. Also carbon-tetra-chloride and chloropicrin were identified.Mutagenicity of the recovered substances was estimated by the preincubation method of Ames test with Salmonella typhimurium TA 98 or 100 strain. The substances recovered gave significant amount of revertants, and the number of revertants was dose-dependent, indicating that the water contain direct mutagenic substances. Also, the recovered substances gave significant amount of revertants in the presence of S9mix, indicating that the metabolite of recovered substances from these points should be mutagenic. A sample showed weak positive mutagenicity in the absence of S9mix but not in the presence of S9mix. The facts suggest that the sample had indirect mutagen but its activity should be very weak. Mutagenic substances in Nakdong and Kumho River should be frame-shift type.The computer-aided system could estimate pollution loads from the basin including both point and non-point sources and to predict quality of the water bodies based on the present load and expected loads after alternative management plans are implemented. The major source of pollution was night soil and gray water discharged form City of Taegu. Also paddy fields, agricultural lands and forests contributed in rural areas. Less