论文标题:广东城市湖泊沉积物营养盐垂直变化特征研究
Vertical Changes of Nutrients in the Sediments of Urban Lakes in Guangdong
论文作者
论文导师 刘正文,论文学位 硕士,论文专业 环境科学
论文单位 暨南大学,点击次数 325,论文页数 62页File Size2970K
2006-05-01论文网 http://www.lw23.com/lunwen_356327/
sediment; nutrient; vertical distribution; phosphorus forms; release flux; urban lake; Guangdong Province
城市浅水湖泊在城市生态环境中起着重要作用，但许多湖泊正面临着严重的富营养化问题。湖泊沉积物的污染严重影响了水环境治理的进程。沉积物中污染物质的分布、赋存特征和释放规律研究，对修复湖泊生态系统具有重要意义。本文以广东省13个城市湖泊为研究对象，采用野外采样、实验室分析和室内模拟结合的方法，以研究其沉积物性质及释放为重点，旨在揭示该地区湖泊沉积物营养盐垂直分布特点以及营养盐释放规律，为防治该地区湖泊富营养化提供参考。实验结论如下： 1、广东省城市湖泊沉积物中的营养盐存在表层富集的现象，揭示了近年来污染加重的趋势。总磷剖面含量范围为0.24-4.76mg·g~(-1)，平均含量为0.35-4.00mg·g~(-1)，总氮平均含量为0.76-6.75mg·g~(-1)，烧失量一般处于5-15％左右。 2、磷形态分析的结果表明，广东省城市湖泊沉积物中无机磷的主要赋存形态为NaOH-P，各湖沉积物中各形态无机磷的含量高低顺序为：NaOH-P最高，NH_4Cl-P最低，BD-P和HCl-P则各采样点情况不尽相同。沉积物BAP含量0.20-2.44mg·g~(-1)，BAP含量分别占到了TP含量的14.12％-80.74％，有一半以上的湖泊超过了50％，具有较大释磷潜力。 3、广东省城市湖泊沉积物营养盐含量显示出较大的地区差异性。城市中心地区湖泊沉积物氮磷含量总体上高于星湖等城郊湖泊。城市化的发展加剧了湖泊的富营养化水平。 4、惠州西湖沉积物氮磷释放试验表明，磷的平均释放通量范围-6.42～-0.80mg·m~(-2)·d~(-1)，氨氮平均释放通量范围-31.64～82.12mg·m~(-2)·d~(-1)。总体上沉积物是水体中磷素的“汇”，氮素的“源”。
Shallow lakes playing an important role in urban ecological environment, but many shallow lakes are confronted with the process of sever eutrophication. Polluted sediment block the harnessing progress of aquatic environment. It"s significant for restoring lake ecological system to strengthen the research of the distribution and chemical forms of and release from sediment. In this paper, we investigated the sediments of thirteen urban lakes in Guangdong with the means of field research, sample analyze and simulation of study in lab. The study on character of sediments and nutrient release is primary. The aim is to reveal the vertical characteristic of sediment and nitrogen and phosphorus release. The study should benefit the precaution of eutrophication of these lakes. The result showed that,1. The distributions of nutrients in lake sediments showed surface enrichment, which suggested that pollution in this area were becoming more serious in recent years. The mean TP contents in sediments ranged from 0.35 mg·g -1 to 4.00 mg·g -1, and the mean TN content ranged from 0.76 mg·g~(-1) to 6.75 mg·g~(-1), and the LOI ranged from 5% to 10 %..2. The inorganic sedimentary phosphorus consisted mainly of NaOH-P. The concentrations of different phosphorus forms followed the order: NaOH-P content was the highest in the four inorganic phosphorus forms and NH_4Cl-P was the lowest, While the rank order of BD-P and HCl-P content were not similar in different lake sediments. BAP contents in sediments ranged from 0.20 to 2.44 mg·g~(-1), accouting for 14.12 %-80.74 % of TP and more than half lakes sediments were above 50 %, which indicated the great potential nutrients release capacity of the sediments.3. The distributions of nutrients in lake sediments of Guangdong Province showed great regional diversities. The nutrient contents in urban areas were higher than that in suburbs. The process of urbanization accelerated the eutrophication level of lakes.4. The nutrients release of lake sediments were summarized through the simulated experiment of sediment cores from Huizhou West Lake, and the results
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