封闭景观水体的表观污染机制研究

良好的表观性状是城市水体发挥景观功能的基本条件,现今封闭景观水体的表观受污染严重。以景观园林师陶园内的封闭水体为研究对象,进行为期半年的现场观察和水质监测,运用吸收光谱法研究了水体表观污染的历程,并进行了表观污染指数(SPI)及环境因子间的相关性分析以了解表观污染机制。研究发现,封闭水体的表观污染程度随季节变化明显,SPI与温度(T)、浊度、腐殖酸(UV254)、叶绿素a(Chl-a)均显著正相关,与溶解氧(DO)显著负相关,相关系数分别为0.786、0.951、0.595、0.849、-0.699。结果表明,植物残体的腐烂分解以及浮萍和藻类的竞争性生长会导致水体颜色和浊度异常,甚至出现发黑发臭的严重表观污染现象。

APPARENT POLLUTION MECHANISM IN THE ENCLOSED LANDSCAPE WATER

Good appearance is the basic condition to play a role in landscape function for urban water． However，the appearance of enclosed landscape water is in serious pollution now． This paper conducted about half a year’s observation and water quality monitoring in the enclosed water located in Shitao Garden． The course of apparent pollution was described by absorption spectrometry． Meanwhile the correlations of sensation pollution index ( SPI ) and environmental factors were analyzed to study the apparent pollution mechanism． The apparent pollution in enclosed water varied markedly with the season． SPI had a significant positive correlation with temperature，turbidity，UV254 ，Chl-a and a negative correlation with DO． The correlation coefficients were 0. 786， 0. 951， 0. 595， 0. 849，－ 0. 699，respectively． The decomposition of plant residues and the competitive growth of algae and duckweed would result in the anormaly of color and turbidity，and even the serious apparent pollution with black-odor phenomenon．