• 研究简报 •

连作对欧美杨I-107叶片主要养分元素化学计量特征的影响

1. 1. 山东泰山森林生态系统国家定位观测研究站 泰安 271018;
2. 山东农业大学农业生态与环境重点实验室 泰安 271018
• 收稿日期:2015-08-12 修回日期:2017-04-21 出版日期:2017-05-25 发布日期:2017-06-22
• 通讯作者: 张彩虹
• 基金资助:
山东省联合专项“暖温带优势造林树种叶片凋落物分解的混合效应及其主要酶控制机制”（ZR2014CL005）；教育部博士点基金“基于生态因子场的拟法正农田林网可持续更新机制研究”（20133702110007）；国家自然科学基金“黄泛平原农田林网生态因子场形成机制研究”（31170662）。

The Effects of Continuous Cropping on Major Nutrient Elements and C/N/P Stoichiometric Ratios of Leaf of Populus×euramericana ‘Neva’

Li Kun1,2, Li Chuanrong1,2, Yang Huanxiang2, Liang Qiang2, Liu Lili2, Zhang Caihong1,2

1. 1. 018;
2. Key Laboratory of Agricultural Ecology and Environment, Shandong Agricultural University Tai’an 271018
• Received:2015-08-12 Revised:2017-04-21 Online:2017-05-25 Published:2017-06-22

Abstract: [Objective]The objective of this study was to provide theoretical basis for reasonable management of Populus×euramericana ‘Neva’ plantations under different continuous cropping conditions. [Method]An Populus×euramericana ‘Neva’ plantation along Dawen River area was studied. The contents of major nutrient elements in leaves were measured. The variations of stoichiometric ratios and nutrient recovery under different continuous cropping conditions were analyzed. [Result]P and K contents in mature leaves of third generation plantation were significantly lower than those of first and second generations (P<0.05), while the content differences were not significant between the first and second generations (P>0.05), respectively. The effect of continuous cropping on N content was minor. Meanwhile, N, P, and K contents in leaf litters increased due to continuous cropping, especially for those in the third generation plantation. As a result, the recovery rates of N, P, and K in the third generation were significantly lower than those in the first and the second generations (P<0.05), respectively. Moreover, the recovery rate of K was significantly higher than those of N and P (P<0.05), respectively. The stoichiometric ratios of C/N, C/P, and N/P in leaf litters were generally higher than those in mature leaves, respectively. The ratios of N/P and C/P in mature leaves of the third-generation plantation were obviously higher than those of the first and the second generations, however, there were no significant differences among C/N ratios in mature leaves of three generation plantations. With the increase of continuous cropping generations, no obvious variation trend was observed on stoichiometric ratios of C, N, and P in leaf litters. The ratios of N/P and C/P in leaf litters of the first generation were significantly higher than those of the second and the third generations (P<0.05), respectively, while the C/N ratio of the second generation was significantly higher than those of the first and the third generations (P<0.05).[Conclusion]Overall, continuous cropping could reduce the contents of P and K in mature leaves, increase N, P, and K contents in leaf litters, and reduce the nutrient recovery ratio of Populus×euramericana ‘Neva’. The internal circle of nutrients was therefore influenced. In addition, continuous cropping could reduce the decomposition rate of litters and affect the variations of C, N, and P contents in the soil by reducing N/P and C/P ratios in leaf litters.