Abstract:

Lignin chemically extracted from pulp waste liquor has been used as a sand fixer in an experiment of sand stabilization in 2001—2003 in a semiarid area in Ningxia. The results obtained were summarized as follows:1)the sand crusts were formed within 24 hours after spraying the lignin sand-fixer on the sand surface. The lignin sand-fixer reduced the cost more than 50% as compared with that of the grass-grid. The fixed sand could increase the height as much as 2/3 of the sand dune that could create favorable conditions for restoration of vegetation and biodiversity. 2)A desirable result was obtained by spraying the solution of 1%～2% lignin sand-fixer in a dose of 2.5 L·m^-2 on sand surface. As a result of reducing evaporation,consequently the moisture was favorable for seed germination,plant growth,and accumulation of biomass and final restoration of vegetation. 3)Lignin sand-fixer was water-soluble and could maintain sand-fixed for 8～12 months in semiarid area,which was enough for plant growth. 4)Sand could be fixed continuously by combining the annual herbs and the perennial shrubs.

Key words: lignin, sand fixation, vegetation restoration