嘉陵江下游鱼类群落与环境因子的关系及生物完整性评价

发布时间：2018-06-01 13:25

本文选题：嘉陵江下游 + 鱼类　；参考：《西南大学》2017年硕士论文

【摘要】：近年来,应用鱼类生物完整性指数(F-IBI)来评价河流健康的研究方法已经得到非常好的推广和完善,有学者提出,在关注鱼类生物完整性的同时还应着重探讨鱼类群落与环境因子的关系。本研究于2015年8月至2016年7月对嘉陵江下游五个采样江段的鱼类群落及水质状况进行了调查。采用典范对应分析(CCA)探讨了影响嘉陵江下游鱼类群落的主要环境因子。采用属性分类筛选、分布范围筛选、判别能力分析以及Pearson相关性分析,构建了适合嘉陵江下游的鱼类生物完整性指数指标体系。主要研究结果如下:(1)本次调查共采集到鱼类8848尾,62种(不包括外来种),分属5目9科。鲤科鱼类种类数最多,占总种类数的60.32%。根据渔获量,目前嘉陵江下游主要经济鱼类为鲤、光泽黄颡鱼、大鳍溹、翘嘴湆、吻泩、鲫、瓦氏黄颡鱼等。草街大坝下游水域以中下层、底层鱼类为主,物种相对丰富,种群间物种数量分布均匀,群落的稳定性较好;而草街库区以中上层、底层鱼类为主,物种单一,群落结构简单,种群间物种数量差异大。根据Shannon-Wiener多样性指数、Pielou均匀度指数和Margalef丰富度指数可以看出,嘉陵江下游坝上、坝下各江段鱼类群落组成已经出现明显差异。(2)主成分分析表明,嘉陵江下游主要水环境理化因子为溶氧、高锰酸盐指数和氨氮;主要水文地貌因子为流速和河宽。典范对应分析表明,与嘉陵江下游鱼类群落关系密切的环境因子为高锰酸盐指数、氨氮、流速和溶氧。从CCA排序图可以看出,由于草街大坝的阻隔,水土、磁器口江段与盐井、金子江段的鱼类群落差异明显。草街大坝的建设将嘉陵江下游切割成两个部分,即大坝上游静水或缓流水河段和大坝下游流水河段,坝上、坝下水体理化因子及水文情势的改变是显而易见的,尤其是营养盐类和流速。根据研究结果可以得出结论,大坝建设是造成嘉陵江下游水域生态环境改变的主要原因,也是影响鱼类群落组成的主要因素。(3)对38个备选指标进行属性分类筛选、分布范围检验、判别能力分析及Pearson相关性分析,构建了适合嘉陵江下游的鱼类生物完整性指数指标体系,即香农多样性指数、鲤形目鱼类种类数、鲇形目鱼类种类数、中下层鱼类物种数百分比、敏感性鱼类物种数百分比、杂食性鱼类个体数百分比、产漂流性卵鱼类个体数百分比等7个参数指标。采用1、3、5赋值法和比值法两种评价方法对嘉陵江下游鱼类生物完整性进行评价,结果显示,金子江段为“健康”,水土和磁器口江段处于“健康”向“亚健康”过渡状态,合川江段为“亚健康”,盐井江段为“一般”。总的来说,金子江段评价最好,受到人为干扰最小;而盐井江段评价最差,受到人为干扰最大。
[Abstract]:In recent years, the application of fish biological integrity index (F-IBI) to evaluate the health of rivers has been well promoted and improved. The relationship between fish community and environmental factors should also be discussed while paying close attention to the biological integrity of fish. From August 2015 to July 2016, the fish community and water quality of five sampling sections in the lower reaches of Jialing River were investigated. The main environmental factors affecting fish communities in the lower reaches of Jialing River were studied by canonical correspondence analysis (CCAA). The index system of fish biological integrity index suitable for the lower reaches of Jialing River was constructed by attribute classification screening, distribution range screening, discriminant ability analysis and Pearson correlation analysis. The main results are as follows: 1) A total of 62 species (excluding exotic species, belonging to 5 orders, 9 families) were collected. Cyprinidae has the largest number of fish species, accounting for 60.32% of the total species. According to the catch, the main economic fishes in the lower reaches of Jialing River are common carp, Pelteobagrus fulvidraco, Fagophora macrophylla, Phellodendron obvidraco, Carassius auratus and Pelteobagrus obvidraco. The lower reaches of the Caojie Dam are dominated by lower middle and lower layers with relatively abundant species, even distribution of species among populations, and good community stability, while in the Caojie Reservoir area, the upper and upper layers are the main species, the species is single, and the community structure is simple. The number of species varies greatly among populations. According to Shannon-Wiener diversity index and Margalef richness index, it can be seen that the composition of fish communities in the lower reaches of the Jialing River and the lower reaches of the dam has been obviously different. The main physical and chemical factors of water environment in the lower reaches of Jialing River are dissolved oxygen, permanganate index and ammonia nitrogen, and the main hydro-geomorphological factors are velocity of flow and width of river. Canonical correspondence analysis showed that the environmental factors closely related to the fish community in the lower reaches of Jialing River were permanganate index, ammonia nitrogen, flow rate and dissolved oxygen. It can be seen from the CCA sequence diagram that the fish communities of the Caijie dam, the water and soil, the river section of Ciqikou, the salt well and the section of the Jinjiang River are obviously different from each other. The construction of Caojie Dam divides the lower reaches of Jialing River into two parts, that is, the static or slow flowing water reach of the upper reaches of the dam and the downstream of the dam. The changes of the physical and chemical factors and the hydrological situation of the water body in the upper and lower reaches of the dam are obvious. In particular, nutrients, salts and flow rates. According to the results of the study, it can be concluded that dam construction is the main reason for the ecological environment change in the lower reaches of Jialing River, and it is also the main factor affecting the composition of fish communities. The distribution range test, discriminant ability analysis and Pearson correlation analysis were used to construct the index system of fish biological integrity index for the lower reaches of Jialing River, namely Shannon diversity index, the number of fish species of Cyprinidae and the number of catfish species. There are seven parameters, such as the percentage of species of middle and lower fish, the percentage of species of sensitive fish, the percentage of individuals of omnivorous fish, and the percentage of individuals of drift-producing eggs. The biological integrity of fish in the lower reaches of the Jialing River was evaluated by two evaluation methods, I. e., the evaluation method of 1 ~ 3 ~ 3 ~ (-5) value and the method of ratio. The result shows that the section of the Jinjiang River is "healthy", and the section of water, soil and water and soil is in a state of transition from "health" to "sub-health". The Hechuan section is sub-healthy and the salt well section is general. On the whole, the evaluation of the Jinjiang section is the best, and that of the Yanjing section is the least, while the evaluation of the Yanjing section is the worst and the most affected by human disturbance.
【学位授予单位】：西南大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：S931

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