Impacts of nitrogen addition on foliar nitrogen and phosphorus stoichiometry in a subtropical evergreen broad-leaved forest in Mount Wuyi
Impacts of nitrogen addition on foliar nitrogen and phosphorus stoichiometry in a subtropical evergreen broad-leaved forest in Mount Wuyi
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DOI：
10.17521/cjpe.2016.0110
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发表时间：
2016
影响因子：
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通讯作者：
Qiaohan Wang;Chengzhi Zheng;Xin-Yang Zhang;Zeng Faxu;A. Juan
中科院分区：
文献类型：
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作者：
Qiaohan Wang;Chengzhi Zheng;Xin-Yang Zhang;Zeng Faxu;A. Juan
目的探讨氮素添加对植物叶片氮、磷和氮磷比的影响，并分析不同植物和功能群间的差异。方法自2011年起，在福建武夷山亚热带万年青阔叶林中进行氮素添加试验。在2013年至2015年的氮添加处理后，测量了树木，灌木，草本植物，蕨类植物和苔藓物种的氮和磷的叶片浓度，并估计了叶片化学计量。重要发现一般来说，几乎所有物种的叶片氮增加，草本植物比树木和灌木更敏感的N添加。米槠、砂仁、狗脊叶片氮含量在施氮处理下显著增加。大多数植物的叶片磷对氮素敏感。草本植物叶片磷含量显著增加，而绿叶白发藓叶片磷含量显著降低。结果表明，武夷山亚热带万年青林主要受磷限制，施氮后N：P平均值由18.67提高到19.72，说明施氮增强了对磷的限制。群落中乔木优势种的N：P比值趋于稳定，草本植物和灌木的N：P比值呈上升趋势。在氮素添加条件下，氮磷比的变化主要由磷素动态而不是氮素动态决定，这表明增加氮素有效性可以影响磷素循环。
Aims Our purpose was to explore the effects of nitrogen addition on foliar nitrogen (N), phosphorus (P) and N:P stoichiometry and to assess their differences among different species and functional groups. Methods N addition experiment has been conducted in a subtropical evergreen broad-leaved forest in Mount Wuyi, Fujian Province since 2011. Foliar concentrations of nitrogen and phosphorus were measured and foliar stoichiometry was estimated in tree, shrub, herb, fern and moss species following the N addition treatments from 2013 to 2015. Important findings Generally, foliar N increased for almost all species and herbaceous plants are much more sensitive than trees and shrubs under N addition. Foliar N of Castanopsis carlesii, Amomum villosum, Woodwardia japonica increased significantly under N addition. Foliar P for most species was sensitive to the N addition. Foliar P of herbaceous plants increased significantly but foliar P of Leucobryum chlorophyllosum decreased significantly. The results showed the subtropical evergreen forest in Mount Wuyi was mainly limited by P and mean foliar N:P ratios enhanced from 18.67 to 19.72 under N addition, indicating that the strength of P limitation was enhanced by N addition. N:P ratios of the dominant arboreal species in the communities tended to be stable, while N:P ratios of herbaceous plants and shrubs increased. The changes in N:P ratios were mainly determined by P dynamics instead of N dynamics under N addition, and our results confirmed that increasing N availability can affect P cycling.