垃圾填埋场渗滤液灌溉地土壤和植物中重金属积累

分加在广州市李坑垃圾填埋场有渗滤液回灌的地表和未经渗滤液回灌的地表随机采集土样,深度达１ｍ,同时分别采集长于灌溉地和非灌溉地上的三个优势植物种（牛筋草,孔雀稗和狗牙根）为代表,调查渗滤液灌溉后封和植物的重金属（Ｃｕ,Ｚｎ,Ｐｂ,Ｃｄ）积累效应。结果表明,渗滤液灌溉地的不同深度土壤和地表植物体内都有不同程度重金属积累。经ｔ－检验,Ｃｕ,Ｐｂ和Ｃｄ在所调查的各土层内的积累效应α＝０．０５时都达到显著水

ACCUMULATION OF HEAVY METAL IN SOIL AND PLANT IRRIGATED WITH GARBAGE LANDFILL LEACHATE

Two adjacent sites of Li Keng landfill, Guangzhou City, one having been irrigated with leachate for two years and the adjacent site having not not received leachate, were surveyed to assess the accumulation of heavy metals (Cu, Zn, Pb and Cd) in soil and in plant after landfill leachate irrigation. Furthermore, the differences of three main plants, Eleusine indica, Paspalum thunbergii and Cyndon dactylon, dominated the two sites, in the above heavy metal contents between occurred on leachate irrigated site and leachate unirrigated site were analyzed comparatively. The results showed that all heavy metal measured displayed evident accumulation throughout profile at 0.05 level except Zn, evident accumulation for Zn only occurred in 0～20 cm upper layer, the accumulation of heavy metals in irrigated soil decreased with depth. Plants sampled from the leachate-irrigated site had higher contents of heavy metals than that sampled from site not receiving leachate. But the difference in heavy content in plant was not significant between occurred on landfill leachate irrigated site and unirrigated site except Cd, suggested these species had tolerance to heavy metal to a certain extent. Fig 2, Tab 3, Ref 17