武陵源水体环境质量现状分析及评价

武陵源自1992年被列为世界自然遗产以来,由于重开发、轻保护,其水体环境受到了明显影响,水体质量基本上呈现逐年下降的趋势。本文选取对水体环境质量影响较大的BOD5、COD、TN、TP、As、MnO4-作为评价因子,对武陵源主要水系金鞭溪和索溪沿途4个主要断面进行监测,并利用模糊综合评价法,进一步研究武陵源水体污染程度,探讨武陵源水体环境变化规律。评价结果显示:水绕四门、吴家峪口、紫草潭断面的水体质量级别为II级,老磨湾断面的水体质量级别为III级,评价结果与实际监测数据基本一致。在此基础上,有针对性地提出了水体环境质量改善措施,为提高世界自然遗产地武陵源水体环境质量提供科学依据。

Situation and evaluation of water environmental quality in Wulingyuan world natural heritage site

Since China joined in the Convention Concerning the Protection of the World Cultural and Natural Heritage in 1985, 37 Chinese cultural relics and scenic spots have been listed in the world heritages, 7 of which are the natural sites. Every country, the United Nations and other international organizations have attached greater importance to the heritage protection and utilization, which has been a hot cultural issue nowadays. In 1992, Wulingyuan was added into the world heritage list. Due to overexploitation and lack of protection, the water environment has been severely affected and its quality has been degraded gradually since then. Based on the current researches, this paper further explores the level of water pollution and discusses the changing pattern of water environment. Because the water environment is a complex and changeable system, it is difficult to evaluate the water quality by the conventional quantitative method. This paper selects BOD₅, COD, TN, TP, As, MnO^-₄ as evaluation factors, which have greater influence on the environment. Four main spots along the major water systems Jinbianxi and Suoxi are monitored. With fuzzy comprehensive evaluation method, we adopt the standard value of pollutants to calculate the weights, and select the weights according to different pollution levels to further research the degree of water pollution and to explore its changing pattern. The evaluation results show that the water quality of Shuiraosimen, Wujiayukou, and Zicaotan is level II, and the water quality of Laomowan is level III. The evaluation results are basically in agreement with the real monitoring data. On this basis, we put forward countermeasures to improve water environmental quality, which can provide scientific evidence for enhancing water environment quality of Wulingyuan world natural heritage site.