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沿塔里木河下游荒漠河岸林,选择了荒漠化程度依次加重的5个断面,进行了土壤种子库野外萌发试验。结果表明:①在中度荒漠化区土壤种子库的物种相对丰富(11种),密度较高(892.6粒.m-2);随着荒漠化程度的加剧,土壤种子库物种丰富度、总密度以及多样性指数呈现出明显下降的趋势;②与重度荒漠化区和中度荒漠化区相比,极度荒漠化区土壤种子库中的多年生草本和灌木密度占总密度的百分比有所增加,一年生草本百分比明显降低;③不同荒漠化程度对种子库密度的垂直分布影响不大,70%以上的种子集中在土壤表层0~2 cm深度。综合来看,随着荒漠化程度的加剧,土壤种子库的恢复潜力有所下降。
Along the desert riparian forest in the lower reaches of the Tarim River, five sections with successively increasing degrees of desertification were chosen to conduct the field germination test of the soil seed bank. The results showed that: (1) The species richness of soil seed bank was relatively abundant (11 species) and the density was relatively high (892.6 grains · m-2) in moderate desertification area. With the intensification of desertification, species richness, total density (2) Compared with the severe desertification area and the moderate desertification area, the diversity index of perennial herbaceous and shrubs in the extremely desertification area increased as a percentage of the total density and the percentage of annual herbaceous plants decreased significantly ; ③Different degrees of desertification have little effect on the vertical distribution of seed bank density, and more than 70% of the seeds are concentrated in the depth of 0-2 cm on the soil surface. Taken together, with the intensification of desertification, the potential for restoration of soil seed banks has declined.