不同树种的固沙林地,其有机质含量和沙地颗粒组成及对植物群丛的形成演替、沙地改良等作用,都有明显不同。了解各固沙树种对沙地性质的改良效果,对合理选择造林树种,提高造林质量,加速改造沙地性质,具有重要意义。现将榆林地区治沙研究所红石峡实验林地,六种主要固沙先锋树种花棒(Hedysarum scoparium Fisch.etMey.)、踏郎(H.mougolicum Tur.)、紫穗槐(Amorpha,futicosa L.)、柠条(Cara-gana microphylla(Pall.)Lam.)、酸刺(Hippophae rhamnoides L.)、沙柳(Salixpsammophila Wanget yanger.)的林地有 Different species of sand-fixing forest, the organic matter content and sand particle composition and succession of the formation of plant communities, sandy land improvement and other effects, are significantly different. It is of great significance to understand the effect of sand fixation on the nature of sandy land. It is of great significance to select the appropriate tree species for afforestation, improve the quality of afforestation and accelerate the transformation of sandy land. At present, the Hedysarum scoparium Fisch.et Meyer., H. mougolicum Tur., Amorpha, futicosa L., ), Cara-gana microphylla (Pall.) Lam., Hippophae rhamnoides L., Salix psammophila Wanget yanger.