Abstract: This paper studied the effects of exotic and native dissolved organic matter (DOM) on the phenanthrene adsorption by three soils differed in soil organic carbon content (f_oc). The exotic DOM came from decayed rice straw, while the native DOM was extracted from the test soils. In all cases, the adsorption of phenanthrene by treated soils could be well described with linear-type mod-el, and there was a positive correlation between adsorption coefficient (K_d) and f_oc. Compared with the control, the K_d value of test soils after native DOM removed was increased by 7.08%—21.4%, and the increment (ΔK_d) was positively correlated with f_oc, indicating that the presence of soil native DOM impeded the phenanthrene adsorption by soil. The effects of exotic DOM on phenan-threne adsorption had a close relation with its added concentration in soil-water system. Within the range of 0—106 mg DOC·L^-1, the K_d value increased first, and then decreased with the increase of added exotic DOM concentration. Lower concentrations of added exotic DOM promoted the phe-nanthrene adsorption by soil, while higher concentrations (≥52 mg DOC·L^-1) of it obviously im-peded this adsorption. These effects of exotic and native DOM on soil phenanthrene adsorption were considered to be related to the association of phenanthrene with DOM in solution, and the ‘cumulative adsorption effect’ between soil solid and aqueous phases.

Key words: Pinits yunnanenensis, Leptagraphium yunnanense, Tomicus piniperda, Temperature, Resistance