关键词: 干旱荒漠区, 人工植物群落, 演替模式, 生态学机制

Abstract: Taking the secondary forest in Maoershan Mountain of Northeast China as study object, the biomass allocation of its understory plants (including tree-like plants and typical shrub categories) was investigated, and the allometry of the components biomass (foliage M_L, new branch M_NB, old branch M_OB, small root M_SR, large root M_LR, branch M_BR, aboveground M_AG, and belowground M_BG) versus each other and each component biomass against plant size was analyzed. The biomass allocation of the understory plants complied with allometry theory, and the allometry power exponents of the components biomass were plastic. The M_L∝M_NB(0.924-1.055), M_OB∝M_LR (0.917-1.024), M_BR∝M_LR (1.095-1.164), and M_AG∝M_BG (1.064-1.125) were isometry, the power (0.585-0.700) of new branch biomass scaling old branch biomass was nearly to 0.67, the foliage biomass nearly scaled the 0.75 power of branch biomass (0.742-0.795), the power exponent (0.853-0.918) of foliage biomass scaling root biomass was nearly to 0.86, and the allometry power of small root biomass scaling large root biomass was 0.658-0.750. The biomass allocation of understory plants complied with allometry partitioning theory, and the component biomass proportions of foliage, new branch, old branch, small root, and large root were 5.83%-20.60%, 0.83%-7.42%, 36.25%-68.24%, 1.32%-6.75%, and 16.38%-42.88%, respectively, with the root/shoot ratio being 0.272-0.866. The plant biomass allocation partitioning varied with plant species and plant size. For understory plants, the biomass allocation of foliage, new branch, and small root and the root/shoot ratio -decreased significantly (P<0.05) with plant growing, and the proportion of old branch biomass in plant biomass increased significantly (P<0.05), only for a few plants, the allocation of large root biomass did not vary significantly (P>0.05).

Key words: Arid desert region, Artificial plant community, Succession pattern, Ecological mechanism