Jing Yan Li, Liu Shi Rong, Yin You, Yao Rong Sheng, Zhang Shao Qiang, Mao Ri Xin
Shenyang Agricultural University, Shenyang 110866, China.
State Forestry Administration Key Laboratory of Forest Ecology and Environment, Research Institute of Forest Ecology, Environment and Protection, Chinese Academy of Forestry, Beijing 100091, China.
Ying Yong Sheng Tai Xue Bao. 2018 Jun;29(6):1753-1758. doi: 10.13287/j.1001-9332.201806.020.
Soil microbial residues are important components of soil stable carbon (C) pools. How N-fixing tree species influence microbial residues in soil aggregates in larch plantations is still unclear. To determine the effects of N-fixing tree species on the distribution of microbial residues in different aggregates, we compared the distribution of amino sugars, biomarker of microbial residues, among aggregates in a pure larch (Larix kaempferi) plantation and a mixed plantation of larch (Larix kaempferi) and alder (Alnus sibirica) in eastern Liaoning Province. The results showed that alder did not affect the distribution of amino sugars, but significantly increased amino sugars content in soil aggregates. The total amino sugars in different soil aggregates were enriched by 130%-170% in the mixed larch plantation compared with those in pure larch plantation. The contributions of glucosamine, galactosamine and muramic acid to the increases of total amino sugars caused by alder introduction were 66.5%-66.9%, 30.0%-30.6% and 2.5%-3.2%, respectively. Alder introduction significantly accelerated the glucosamine/muramic acid ratios in >2000 μm and <250 μm aggregates, but not in 250-2000 μm aggregates. Moreover, alder introduction increased the microbial contribution to soil organic C in all aggregates, but did not influence this contribution among aggregates, indicating that the effects of alder introduction on microbial contribution to aggregates were homogeneous.
土壤微生物残体是土壤稳定碳库的重要组成部分。固氮树种如何影响落叶松人工林土壤团聚体中的微生物残体仍不清楚。为了确定固氮树种对不同团聚体中微生物残体分布的影响，我们比较了辽东地区纯落叶松（日本落叶松）人工林和落叶松（日本落叶松）与桤木（西伯利亚桤木）混交林中团聚体间微生物残体生物标志物氨基糖的分布。结果表明，桤木对氨基糖的分布没有影响，但显著增加了土壤团聚体中氨基糖的含量。与纯落叶松人工林相比，落叶松混交林中不同土壤团聚体中的总氨基糖含量提高了130%-170%。引入桤木导致总氨基糖增加，其中氨基葡萄糖、半乳糖胺和胞壁酸的贡献分别为66.5%-66.9%、30.0%-30.6%和2.5%-3.2%。引入桤木显著提高了>2000μm和<250μm团聚体中的氨基葡萄糖/胞壁酸比值，但对250-2000μm团聚体没有影响。此外，引入桤木增加了所有团聚体中微生物对土壤有机碳的贡献，但没有影响团聚体间的这种贡献，这表明引入桤木对微生物对团聚体贡献的影响是均匀的。
