【作者】 李雷；

【导师】 戴万宏；

【作者基本信息】 安徽师范大学 ， 环境科学， 2010， 硕士

【摘要】 湖泊富营养化是目前国际共同关注的生态环境研究热点和前沿领域。我国湖泊资源丰富,类型多样,湖泊以其自身的丰富资源以及巨大的生态功能对人类社会经济的发展起到了不可忽视的重大作用。相关研究资料表明:湖泊富营养化是目前制约我国湖泊可持续发展的首要问题,巢湖是我国五大淡水湖之一,近年来,因自然和人为因素,湖体富营养化现象严重,水质恶化加剧,严重制约了流域社会经济可持续发展。本研究以富营养化严重的浅水型湖泊巢湖为研究对象,以分析巢湖湿地沉积物中有机碳、氮、磷含量的分布特征为主要研究内容,系统地研究了营养盐在巢湖湿地沉积物中的分布规律及其和各种环境介质间的相互关系,揭示了巢湖湿地的富营养化进程及内源污染机制,为了解和掌握巢湖湿地的富营养化内源污染状况、制定和实施巢湖湿地富营养化的防治和修复提供了科学依据。本论文研究工作所取得的主要成果如下:1.巢湖湿地沉积物中有机碳、氮、磷含量具有明显的垂直剖面分布特征,表层土沉积物中碳、氮、磷含量最高,表现出明显富集现象,随着剖面深度的加深,沉积物中碳、氮、磷含量虽有波折但大致呈递减趋势,至底层达到最低。2.巢湖湿地沉积物表层有机碳、氮、磷含量普遍较高;不同地理位置沉积物中碳、氮、磷含量具有明显的差别,总体上西半湖高于东半湖,东半湖个别采样点沉积物中的碳、氮、磷分布出现空间异质化现象,这可能与采样点区域人类的经济活动干预、土壤地球化学背景及矿物组成等的差异有关。水体富营养化现象表现为:西半湖较东半湖严重。3.巢湖湿地沉积物中总有机碳与总氮之间存在较好的相关性,磷依旧是影响巢湖富营养化的限制性营养元素;受湖泊沉积动力、环境因子以及沉积速率等影响,巢湖湿地沉积物中的有机质具有混合来源。4.表层沉积物中TN、TP和有机质的粒度效应明显。并有粉砂、粘土粒级(Ⅳ)>极细砂粒级(Ⅲ)、细砂粒级(Ⅱ)>中砂以上粒级(Ⅰ)的含量序列。5.近年来,随着巢湖流域经济社会的发展,受巢湖富营养化的内源污染以及面源污染影响,巢湖水体富营养化态势仍有进一步加剧的趋势。更多还原

【Abstract】 Lake Eutrophication is highlighted in international eco-environmental research. Lakes, rich in natural resources and important in eco-environment, play an indispensable role in social and economic development. And China possesses a variety of lakes. According to a related survey, it’s mainly Lake Entrophication that restricts the sustainable development of lakes in China. Chao Lake, one of the five freshwater lakes, has seen an increasing water degradation in recent years due to natural and human factors, which retards the sustainable economic and social growth of the areas along the lake.This thesis focuses on Chao Lake of severe entrophication and of shallow water, analyzing the distribution of organic carbon, nitrogen and phosphorus in Chao Lake wetland sediment and of the size of the sediment particles. This thesis also unfolds the entrophication proceeding of Chao Lake wetland and the inner source pollution system, which provides scientific statistics for formulating and implementing measures to prevent and solve the problem of entrophication and pollution.The achievements of this thesis:1. The distribution of organic carbon, nitrogen and phosphorus in Chao Lake wetland sediment is obviously vertical: In general, the amount of carbon, nitrogen and phosphorus decreases with the deepening of the vertical profile in spite of occasional curves.2. The amount of organic carbon, nitrogen and phosphorus in Chao Lake wetland sediment is relatively great in the surface of the soil. In addition, the geographical location of the sediment also determines the amount of these minerals—the western part larger than the eastern part on average. The strange distribution in the eastern part of the lake could be attributed to the disturbance of human economic activities, the chemical features of the soil and the composition of certain minerals, etc. But water entrophication of the western part is more severe than that of the eastern part.3. The total amount of organic carbon and nitrogen is well-balanced while phosphorus is still the main cause of entrophication in Chao Lake. Under the influence of lake dynamic sediment, environmental factor and sedimentation rate, the organic substances in Chao Lake wetland sediment have mixed sources.4. Study on distributional characteristics of TN, TP and Organic mattter in sediments of different grain size showed that the contents of TN, TP, and organic matter had obvious grains-size effect, and the contents were distributed as silt and clay fraction(Ⅳ)> very fine sand fraction(Ⅲ)and fine sand fraction (Ⅱ)> medium sand fraction(Ⅰ)and larger fractions.5. In recent years, with social and economic development of the areas along Chao Lake, Lake Entrophication tends to deteriorate, due to its inner source pollution and outer source pollution.更多还原