Wang Yi-Huan, Jin Yi-Dan, Jiang Ming-Kai, Ma Shu-Qin, Chen You-Chao, Cai Yan-Jiang
State Key Laboratory of Subtropical Silviculture, Zhejiang A&F University, Hangzhou 311300, China.
College of Environment and Resources/College of Carbon Neutrality, Zhejiang A&F University, Hangzhou 311300, China.
Ying Yong Sheng Tai Xue Bao. 2023 Oct;34(10):2593-2600. doi: 10.13287/j.1001-9332.202310.008.
To investigate the effects of short-term nitrogen (N) deposition on organic matter composition of litter and soil in Moso bamboo () forests, we established a N-addition treatments (50 kg N·hm·a) to simulate the ambient and N deposition in a subtropical Moso bamboo forest from July 2020 to January 2022. We analyzed the organic matter composition of Moso bamboo leaf/root litter and soil by using pyrolysis-gas chromatography/mass spectrometry (Py-GC/MS) technique. The results showed that short-term N deposition significantly increased the relative content of soil phenols by 50.9%, while significantly decreased fatty acids by 26.3%. The rela-tive content of alkanes & alkenes and lignin in leaf litter was significantly increased by 51.9% and 33.5%, respectively, while that of phenols and polysaccharides significantly decreased by 52.2% and 56.3%. In root litter, eleva-ted N significantly decreased the relative content of polycyclic aromatic hydrocarbons by 16.6%. Moreover, the relative content of fatty acids in soil organic matter was significantly positively correlated with the relative content of poly-saccharides in leaf litter. The relative content of phenols in soil organic matter was significantly positively correlated with the relative content of lignin, and negatively correlated with the relative content of polysaccharides in leaf litter. Our results demonstrated that short-term N deposition did not change the concentration of total organic carbon, total nitrogen, and C/N of the soil, leaf litter, and root litter, but significantly altered the chemical composition of organic matter. In addition, the changes in chemical composition of organic matter in soil under short-term N deposition were affected by the composition of organic matter in leaf litter.
为研究短期氮（N）沉降对毛竹林凋落物和土壤有机质组成的影响，我们于2020年7月至2022年1月在亚热带毛竹林建立了氮添加处理（50 kg N·hm·a）以模拟环境氮沉降。我们采用热解气相色谱/质谱联用（Py-GC/MS）技术分析了毛竹叶片/根系凋落物和土壤的有机质组成。结果表明，短期氮沉降显著增加了土壤酚类物质的相对含量50.9%，同时显著降低了脂肪酸含量26.3%。叶片凋落物中烷烃和烯烃以及木质素的相对含量分别显著增加51.9%和33.5%，而酚类和多糖的相对含量分别显著降低52.2%和56.3%。在根系凋落物中，氮添加显著降低了多环芳烃的相对含量16.6%。此外，土壤有机质中脂肪酸的相对含量与叶片凋落物中多糖的相对含量显著正相关。土壤有机质中酚类物质的相对含量与木质素的相对含量显著正相关，与叶片凋落物中多糖的相对含量显著负相关。我们的结果表明，短期氮沉降并未改变土壤、叶片凋落物和根系凋落物中总有机碳、总氮和碳氮比的浓度，但显著改变了有机质的化学组成。此外，短期氮沉降下土壤有机质化学组成的变化受叶片凋落物有机质组成的影响。
