Wang Guo-Hua, Wang Jia-Qi, Liu Jing
College of Geographical Sciences, Shanxi Normal University, Taiyuan 030000, China.
Linze Inland River Basin Research Station, Northwest Institute of Eco-Environment and Resources, Chinese Academy of Sciences, Lanzhou 730000, China.
Ying Yong Sheng Tai Xue Bao. 2024 Jan;35(1):62-72. doi: 10.13287/j.1001-9332.202401.004.
We investigated the changes of soil nutrients and plant communities in the artificial sand fixation forests of with different ages. The results showed that soil organic carbon and soil total nitrogen contents increased with the stand ages, and were significantly higher in 40 and 50 year-old than other ages. Soil organic carbon and total nitrogen contents recovered much faster in the surface layer (0-10 cm) than in others. Soil nutrient stoichiometric ratios (C:P, N:P) in the 0-10 cm soil layer differed significantly among different stand ages. With the increases of stand age, C and N contents in leaves increased significantly, and reached the maximum at 50 year-old. Leaf P content increased first and then decreased, being maximum at 18 year-old. Leaf C:N first increased and then decreased, being maximum at 12 year-old. The contents of photosynthetic pigments and leaf C:P and N:P decreased first and then increased, being minimum at 18 year-old. was mainly influenced by N availability before 40 year-old, but mainly limited by P after. The species number, density, and vegetation cover of annual and perennial herbaceous plants increased with stand ages, and the community shifted from a simple shrub plant community to a complex shrub-herb community. The biomass of and herbaceous plants increased significantly with stand age, and had a significant positive correlation with the contents of soil organic carbon, total nitrogen and N:P.
我们调查了不同年龄人工固沙林土壤养分和植物群落的变化。结果表明，土壤有机碳和土壤全氮含量随林龄增加而增加，40年和50年生的显著高于其他林龄。表层（0 - 10厘米）土壤有机碳和全氮含量的恢复速度比其他层快得多。0 - 10厘米土层中土壤养分化学计量比（C:P、N:P）在不同林龄间差异显著。随着林龄增加，叶片中碳和氮含量显著增加，在50年生时达到最大值。叶片磷含量先增加后降低，在18年生时最高。叶片C:N先增加后降低，在12年生时最高。光合色素含量以及叶片C:P和N:P先降低后增加，在18年生时最低。40年生之前主要受氮有效性影响，之后主要受磷限制。一年生和多年生草本植物的物种数、密度和植被覆盖度随林龄增加而增加，群落从简单的灌木植物群落转变为复杂的灌木 - 草本群落。灌木和草本植物生物量随林龄显著增加，且与土壤有机碳、全氮含量及N:P呈显著正相关。
