Abstract: In order to investigate the effect of constructing poplar plantation on soil amelioration, the severe saline-alkali soil of Zhaodong City, Heilongjiang Province was studied. The 4 treatments were CK (Control), Bar treatment (Small hole improvement-Bar foraging ditch-In situ repair), Cross treatment (Small hole improvement-Cross foraging ditch-In situ repair) and Grid treatment (Small hole improvement-Grid form of foraging ditch-In situ repair), respectively. The results of the present study showed that the different improvement treatments changed the severe saline-alkali soil characteristics, significantly decreased the pH value, conductivity and carbonate content in soil surface (p<0.05). Meanwhile, the exchange of calcium and magnesium ion contents, and the humic acid and chitosan contents were significantly increased (p<0.05). Therefore, the 3 different treatments, based on Small hole improvement and In situ repair, had well modified effects for the severe saline-alkali soil.

Key words: Severe saline-alkali soil, poplar, soil characteristics, amelioration performance