流速对城市景观水体表观污染的影响

发布时间：2018-01-26 08:02

本文关键词： 城市景观水体表观污染流速影响因素相关分析　出处：《苏州科技大学》2017年硕士论文　论文类型：学位论文

【摘要】：近几年,因为经济体制的改革,农村城镇的人口大量涌入城市,导致城市人口的大量增长,生活污水和工业废水的排放导致城市河道黑臭和富营养化现象日益严重。苏州作为长三角著名的旅游城市,人口众多,城市水体表观污染严重。让城市中的水体动起来是目前治理城市河道的主要方法。水体在流动的过程中,可以增加水中的溶解氧,从而加快微生物对水中有机物及营养盐的降解速率,在一定的流速下,可以抑制水中的藻类生长,防止水体富营养化的发生。目前有较多研究者通过让水体流动来改善城市河道水质,但这一过程中是否由于改变了流速引起的以及流速如何影响城市表观污染都不明确。基于此,本文主要以苏州市古城区的河道水体为研究对象,探究流速和水体表观之间的关系,并从影响水体表观的影响因素角度和粒径角度对流速对水体表观的作用机制进行分析。得出以下结论:(1)研究区域内,流速在0.031~1.009m/s,SPI值在17.933~77.095之间,在该研究范围内,流速与SPI值显著正相关,相关系数为0.343(p0.05)。随着流速的增大,SPI值先逐渐增加,然后保持在一定水平下不变,流速对水体表观具有较大影响。(2)流速对不同污染类型的河道表观污染的影响方式不一样。对于以无机型河道为主的临顿河上游,流速范围为0.414~1.009m/s,随着流速的增大,SPI值呈下降的趋势,影响显著;以营养主导型为主的官太尉河(官太尉桥河段)、护城河(齐门桥河段)和九曲港(盘蠡桥河段)等,流速范围为0.058~0.776,营养型水体的SPI值基本在45以下,随着流速的增大,SPI值变化并不明显;以混合型为主的平门小河(单家桥河段)、桃花坞河(桃坞桥河段)、临顿河下游(醋坊桥河段)、平江河(东潘儒巷河段)等,流速范围为0.009~0.781,随着流速的增加,SPI值呈线性增加且影响显著。(3)研究区域内,水体粒度分布基本成单峰分布,三种类型的水体分选性极好,属于极正偏,且峰态很尖锐。对于无机型河道,流速主要作用水中的颗粒态营养盐含量来影响水体的SPI值,且无机型水体中粗端粒径大小大于混合型和营养型;针对营养型河道,流速主要通过作用水中的藻类来影响水体的SPI值,但是影响不显著;针对混合型河道,流速通过作用水中的藻类、无机悬浮物含量从而影响水体的SPI值,并且随着流速的增加,水体的无机化水平增加,水体处于向无机型水体过渡的阶段。
[Abstract]:In recent years, due to the reform of the economic system, the population of rural towns has poured into cities, resulting in a large number of urban population growth. As a famous tourist city of Yangtze River Delta, Suzhou has a large population due to the discharge of domestic sewage and industrial wastewater, which leads to the increasingly serious phenomenon of black-smelling and eutrophication in urban watercourses. The apparent pollution of urban water body is serious. It is the main method to control the urban river channel to move the water body in the city. The dissolved oxygen in water can be increased in the process of water flow. In order to accelerate the microbial degradation rate of organic matter and nutrients in water, at a certain flow rate, can inhibit the growth of algae in water. To prevent the occurrence of eutrophication, there are more researchers to improve the water quality of urban watercourses through the flow of water. However, it is not clear whether it is caused by changing the velocity of flow and how the velocity affects the apparent pollution of the city. Based on this, this paper mainly takes the river body of ancient urban area of Suzhou as the research object. Explore the relationship between velocity and water surface, and analyze the action mechanism of velocity on water surface from the angle of influencing factors and particle size. Draw the following conclusion: 1) in the study area. The velocity of flow was 0.031 ~ 1.009 m / s ~ (-1) m 路s ~ (-1). The SPI value was 17.933 ~ 77.095. In the range of the study, the velocity of flow was positively correlated with the SPI value. The correlation coefficient is 0.343p0.050.The SPI value increases gradually with the increase of flow rate, and then remains unchanged at a certain level. Velocity has great influence on the surface of water body. (2) the effect of velocity on the apparent pollution of different types of river channels is different, for the upper reaches of Linton River, where there is no type of river channel. The velocity range was 0.414 ~ 1.009 m / s, and the SPI value decreased with the increase of flow velocity, and the effect was significant. The main nutrition type is Guantai Wei River (Guantai Wei Bridge reach), moat River (Qimenqiao reach) and Jiuqu Port (Panliqiao reach). The velocity range is 0.058 ~ 0.776. The SPI value of nutritious water was below 45, and the change of SPI value was not obvious with the increase of velocity. The mixed type of Pingmen River (Danjiaqiao reach, Taohuawu River), the lower reaches of the Linton River (vinegar Fang Bridge reach, Pingjiang River (East Panru River), etc.) are mainly composed of the mixed type of the Pingmen River (Danjiaqiao reach), the Taohuawu River (Taowu Bridge Section) and the lower Linton River. The velocity range is 0.009 ~ 0.781.The SPI value increases linearly with the increase of flow velocity and the influence is significant.) in the study area, the particle size distribution of water is basically a single peak distribution. The separation of the three types of water is excellent, which belongs to the extreme positive deviation, and the peak state is very sharp. For the channel without model, the velocity of flow mainly affects the content of granular nutrients in the water to affect the SPI value of the water. And the diameter of coarse end in the water without model is larger than that of mixed type and nutrition type. For the nutritious river, the velocity of flow mainly affects the SPI value of the water by the algae in the water, but the effect is not significant. For the mixed channel, the flow velocity affects the SPI value of the water through the effect of algae and inorganic suspended matter content in the water, and with the increase of the velocity, the inorganic level of the water increases. The water body is in the stage of transition to no model water body.
【学位授予单位】：苏州科技大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：X52

【相似文献】