Liu Xu-Yan, Hu Yu-Kun
Beijing Key Laboratory of Wetland Ser-vices and Restoration, Institute of Wetland Research, Chinese Academy of Forestry, Beijing 100091, China.
Key Laboratory of Ecosystem Network Observation and Modeling, Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing 100101, China.
Ying Yong Sheng Tai Xue Bao. 2020 Oct;31(10):3385-3394. doi: 10.13287/j.1001-9332.202010.007.
Investigating ecological stoichiometry of leaves and fine roots of forest swamps in the Greater Hinggan Mountains will improve our understanding of plant nutrient use and material cycling in ecosystems at high latitudes with high sensitivity to climate change. In this study, we collected leaf and fine root samples from 19 dominant and subordinate vascular plant species and measured their C, N and P concentrations in three typical forest swamps (, moss and ) of the Greater Hinggan Mountains, China. We compared C:N:P stoichiometry in leaves and fine roots among different forest swamp types, plant growth forms, and mycorrhizal types. Standardized major axis regression was performed to examine the relationships between leaf and fine root stoichiometry. The results showed that interspecific variation accounted for the largest proportion of total variation in C:N:P stoichiometry of leaves (42.5%-84.6%). N:P had the highest, C:N had the intermediate, and C:P had the lowest interspecific variation in both leaves and fine roots. forest swamps, which had higher soil nutrient and water availability, had lower C:N and C:P in leaves and fine roots. N:P of all three forest swamps were lower than 10, indicating N limitation in this ecosystem. Herbaceous plants had significantly lower leaf C:P, fine root C:N, and fine root C:P than woody species. Both ectomycorrhizal and ericoid mycorrhizal plants had higher leaf and fine root C:N and C:P than arbuscular mycorrhizal and non-mycorrhizal species, while the C:P of ericoid mycorrhizal plants was significantly higher than that of ectomycorrhizal species. Forest swamp type, plant growth form, and mycorrhizal type all had greater influences on leaf and fine root C:N and C:P rather than N:P. Leaf and fine root C:N, C:P, and N:P were positively correlated, indicating strong coordination between plant above- and below-ground C:N:P stoichiometry.
研究大兴安岭森林沼泽中叶片和细根的生态化学计量学，将有助于我们更好地理解高纬度地区对气候变化高度敏感的生态系统中植物养分利用和物质循环。在本研究中，我们从中国大兴安岭地区的三个典型森林沼泽（苔藓和 ）中采集了19种优势和从属维管植物物种的叶片和细根样本，并测量了它们的碳、氮和磷浓度。我们比较了不同森林沼泽类型、植物生长形式和菌根类型之间叶片和细根的碳：氮：磷化学计量学。进行标准化主轴回归以检验叶片和细根化学计量学之间的关系。结果表明，种间变异在叶片碳：氮：磷化学计量学的总变异中占比最大（42.5%-84.6%）。叶片和细根中氮：磷的种间变异最高，碳：氮的种间变异居中，碳：磷的种间变异最低。土壤养分和水分有效性较高的森林沼泽，其叶片和细根中的碳：氮和碳：磷较低。所有三个森林沼泽的氮：磷均低于10，表明该生态系统存在氮限制。草本植物的叶片碳：磷、细根碳：氮和细根碳：磷显著低于木本植物。外生菌根和石楠状菌根植物的叶片和细根碳：氮和碳：磷均高于丛枝菌根和非菌根物种，而石楠状菌根植物的碳：磷显著高于外生菌根物种。森林沼泽类型、植物生长形式和菌根类型对叶片和细根的碳：氮和碳：磷的影响均大于对氮：磷的影响。叶片和细根的碳：氮、碳：磷和氮：磷呈正相关，表明植物地上和地下碳：氮：磷化学计量学之间具有很强的协调性。
