Abstract: A field experiment laid out in the coastal area of salft-affected soil in Dongtai of Jiangsu Province, was carried out to investigate effects of application of dry paper-making waste powder (DPWP) and furfural residue (FR) on soil microbial activity, maize growth and nitrogen (N) accumulation in the soil. Compared to the control, the plots applied with DPWP and FR were significantly lower (P < 0.05) in soil pH and significantly higher (P < 0.05) in soil microbial metabolic activity. The plots applied with FR was also much higher than CK in evenness of soil microbial species (McIntosh index) (P < 0.05), but much lower (P < 0.05) in soil urease activity, which dropped sharply from an excessive high level, 0.50 mg•g^-1•d^-1 , down to 0.33 mg•g^-1•d^-1. In the plots applied with DPWP the maize increased its shoot and root biomass by 29% and 13%, respectively, and its grain yield from 1 119 to 1 515 kg•hm-2, while in the plots applied with FR, the maize significantly increased (P < 0.05) its shoot and root biomass by 60% and 65%, respectively, and its grain yield to 2 371 kg•hm^-2, while it significantly decreased total N concentration in its grains (P < 0.05) from an excessive high level (22.43 mg•g^-1) down to 18.26 mg•g^-1 (P < 0.05). To sum up, the application of either DPWP or FR can alleviate saline-alkaline stresses on maize growth, and increase soil microbial metabolic activities; moreover FR is superior to DPWP in improving soil biological properties and maize grain quality.

Key words: paper-making waste powder, furfural residue, grain N concentration, urease activity, soil microbial functional diversity