沙田人工湿地植物生长特性及除污能力的研究

Growing Characteristics of Several Plants and Their Removal Ability on Pollutants in Shatian Constructed Wetland

采用人工模拟小试系统,研究了沙田人工湿地9种植物的长势、生物量变化及对污染物的去除能力,分析了各种植物的生长特性、环境适应性和在系统中的作用。结果表明,在深圳的气候条件下,植物生长期可贯穿全年,但长势受季节等环境因素的影响仍非常明显。植物茎叶的生物量受收割季节和周期的影响较大,根系的生物量及根区范围随植物收割呈周期性变化。在热带砾石床中,红花美人蕉(Cannaindica)、水葱(S.tabernaemotaniGmel)难以适应环境,芦苇(Ph.australisTrin)、再力花(Thaliadealbata)、荻(M.sacchariflorus)一直生长旺盛,但荻的除污能力较差;纸莎草(Cyperuspapyrus)和美人蕉长速较快,较适合于需快速启动的湿地系统。

This investigation studied growth, biomass variation of several plants in Shatian constructed wetland and their removal ability on pollutants, and discussed the growth characteristics, acclimatization and function of different plants in the constructed wetland treatment system. In the local weather, the growing period of the plants was whole year-round, but seasonal discrepancy could be observed obviously. The growth of the plants had highly positive correlation with their biomasses. The cycle and the season of reaping plants exhibited significant influence on haulm biomass. The root biomass and its area were cyclicalchange with reaping plants. The root area and biomasses of different plants hada large difference. The roots of reed and Sweetcane flower, Silvergrass could penetrate up to a depth of 50 cm. In contrast, the depth of canna root was less than 25 cm. The root biomass of the reed was 1504.2 g, but that of lucky bamboo was only 53.8 g. In tropical gravel bed, red colour canna and great bulrush couldnot acclimatize environment, and reed, powdery thalia and sweetcane flower, silvergrass were flourishing during the whole experimental process, but the removing ability of pollutants by sweetcane flower, silvergrass was very low. Lucky bamboo grew very slowly and its effect on removing ability was very small. Althoughsedge and other two species canna were sensitive to environment, they grow veryquickly and their removal efficiencies of pollutants were satisfactory. So theycould be chosen as a fast start-up constructed wetlands system.