河西走廊人工梭梭林中不同形态与质量植物种子的垂直分布特点

Vertical distribution characteristics of plant seeds with different morphology and quality in Haloxylon ammodendron plantation in Hexi Corridor

通过测定河西走廊中部梭梭人工林中13种荒漠植物种子百粒重、形态方差、单位体积种子质量,分析了其在0~10 cm土层的垂直分布特点.结果表明:(1)13种荒漠植物种子百粒重、形态方差、单位体积种子质量差异较大;(2)在0~10 cm土层中,百粒重在0.500~1.000 g之间的种子在分布密度上占明显优势;(3)形态方差在0.050~0.100之间的种子密度和出现频次都相对占优势,且其在0~2 cm土层中的分布密度较大,随土壤加深密度减小,但出现频次变化不大;(4)单位体积种子质量>500 kg·m^(-3)的种子在分布密度和出现频次上均占明显优势;(5)百粒重较小的种子随土壤深度的增加而减少,百粒重较大的种子随土壤深度的增加而增多.

To investigate the vertical distribution characteristics of the seeds of desert plants in 0-10 cm soil layer along Hexi Corridor, seed weight, morphological variance and seed weight per unit volume of 13 desert plants in Haloxylon ammodendron plantation were analyzed. The results showed that:(1)there were significant differences in seed weight, morphological variance and seed weight per unit volume among 13 desert plants.(2)In 0-10 cm soil layer, the density of the seeds with 100-seed weight being 0.500-1.000 g were high.(3)And the density and frequency of the seeds with total variance of morphology being 0.050-0.100 were relatively high in 0-10 cm soil layer. Seed distribution density was higher in 0-2 cm soil layer, and decreased with deepened soil depth, but with almost constant distribution frequency.(4)The density and frequency of the seeds with seed per unit volume >500 kg·m^(-3) were the highest.(5) The lower quality seeds decreased with the increase of soil depth, while the higher quality seeds increased with the increase of soil depth.