Abstract: A simulation experiment was conducted to study the aging characteristics of hexachlorobenzene (HCB) in different soils and its bioaccumulation in earthworm. The results indicated that the aging of HCB in soils displayed a biphasic characteristic, i.e., quicker in the first 60 days and slowing down since then. The aging of HCB mainly occurred in the first 60 days during its contact with soil, and its aging rate in soils followed the sequence of paddy soil>red soil>fluvo-aquic soil. The accumulated amount and accumulation rate of HCB in earthworm decreased with increasing aging time. Though the soil extractable HCB decreased with increasing aging time, earthworm still had a higher HCB accumulation (4576〖KG-*2〗-〖KG-*7〗9843 ng·g-1) in its body due to its high HCB accumulation ability (the bioaccumulation factor BAF was between 374 and 635), giving a potential risk to soil ecological safety.

Key words: photosynthetic physiology, sap flow rate, Populus ×euramericana cv. ‘74/76’, dye solution introduction