城市景观水体表观污染的悬浮颗粒物粒度分布特征研究

发布时间：2018-01-12 15:42

本文关键词：城市景观水体表观污染的悬浮颗粒物粒度分布特征研究　出处：《苏州科技学院》2015年硕士论文　论文类型：学位论文

【摘要】：随着我国经济的高速发展,城市地表水体污染加剧,水质下降,绝大多数城市地表水体丧失了作为饮用水水源地的功能,主体功能转变为景观功能。由于城市景观水体自身生态脆弱性及人类活动的影响,景观功能亦被严重削弱,城市景观水体表观污染日趋严重。水中悬浮颗粒物是引起城市景观水体表观污染最主要的原因,悬浮颗粒物粒度分布决定着水中颗粒物对光的衰减、吸收和散射作用,进而决定着水体的颜色、透明度、真光层深度等水体表观特征。固悬浮颗粒物粒度分布特征能反映城市景观水体表观污染状况。基于此本研究以苏州市内城市景观水体为研究对象,系统分析水中悬浮颗粒物的粒度分布特征与水体表观污染程度的关系,从悬浮颗粒物粒度角度来解析城市景观水体表观污染效应。得出以下结论:(1)不同表观污染类型城市景观水体中悬浮颗粒物呈现不同的粒度分布特征。黄色城市景观水体悬浮颗粒物粒度主要呈单峰分布,具有分选性较好、峰正态、近对称的分布特征;绿色城市景观水体中悬浮颗粒物粒度主要呈多峰分布,具有分选性差、多组分的分布特征。(2)绿色城市景观水体中悬浮颗粒物对水体表观敏感的粒级是8~35μm,SPI值、Chl-a浓度与该粒级组分体积分数呈显著正相关。此粒级组分体积分数增大是绿色水体表观污染程度加深的粒度结果表征,该组分体积分数增大主要来自于藻含量增加。(3)黄色城市景观水体中悬浮颗粒物对水体表观敏感粒级是3.8~16μm和32~64μm,SPI值与敏感粒级组分体积分数关系具有分段性,分段节点是浊度为45NTU处。浊度小于45NTU时,SPI值与3.8~16μm粒级组分体积分数呈显著正相关,与32~64μm体积分数呈显著负相关;当浊度大于等于45NTU时关系相反。悬浮颗粒物含量达到一定程度时,对SPI值产生贡献的主要是相对大粒级颗粒物。(4)物源因子、环境因子、外源因子和水动力条件等影响因子的改变,在悬浮颗粒物粒度分布和水体表观上呈现一致的响应,悬浮颗粒物粒度分布的改变是产生水体表观污染效应最根本原因。
[Abstract]:With the rapid development of our country's economy, the urban surface water pollution intensifies, the water quality drops, and most of the urban surface water bodies lose their function as the drinking water source. The main body function is transformed into the landscape function. Because of the ecological fragility of the urban landscape water body and the influence of human activities, the landscape function is seriously weakened. The apparent pollution of urban landscape water is becoming more and more serious. Suspended particulate matter in water is the most important cause of surface pollution in urban landscape water. The particle size distribution of suspended particles determines the attenuation of light in water. Absorption and scattering, in turn, determine the color and transparency of the water. The particle size distribution characteristics of solid suspended particles can reflect the apparent pollution of urban landscape water body. Based on this study, the urban landscape water body in Suzhou was taken as the research object. The relationship between the particle size distribution of suspended particles in water and the degree of water surface pollution was analyzed systematically. The apparent pollution effect of urban landscape water body is analyzed from the angle of suspended particle size. The following conclusion is drawn: 1). The particle size distribution of suspended particles in urban landscape water of different apparent pollution types was different. The particle size of yellow urban landscape water was mainly single-peak distribution. It has the characteristics of good sorting, normal peak and nearly symmetrical distribution. The particle size of suspended particles in green urban landscape water is mainly multi-peak distribution, with poor sorting. (2) the apparent sensitivity of suspended particulates in green urban landscape water was 835 渭 m SPI. There was a significant positive correlation between the concentration of Chl-a and the volume fraction of the particle fraction, which was the result of increasing the apparent pollution of green water. The increase of the fraction integral was mainly due to the increase of algae content.) the apparent sensitivity of suspended particulates in yellow urban landscape water was 3.816 渭 m and 32 ~ (64) 渭 m respectively. The relationship between the SPI value and the volume fraction of the sensitive particle is piecewise. The segmental node is at the turbidity of 45NTU and the turbidity is less than 45NTU. The SPI value was positively correlated with the volume fraction of 16 渭 m grains and negatively correlated with the volume fraction of 32 ~ (64) 渭 m. When turbidity is greater than 45NTU, the relationship is opposite. When the content of suspended particles reaches a certain level, the main contribution to the SPI value is relatively large particle size. 4) the source factor and environmental factor. The change of external factors and hydrodynamic conditions showed a consistent response on particle size distribution and water surface. The change of particle size distribution of suspended particles is the most fundamental reason for the effect of water surface pollution.
【学位授予单位】：苏州科技学院
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：X52

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