2013 Fiscal Year Final Research Report
Evaluation of the mid- and long-term effects of thinning on nutrient cycling in sugi and hinoki forests
Project/Area Number |
23580205
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Research Category |
Grant-in-Aid for Scientific Research (C)
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Allocation Type | Multi-year Fund |
Section | 一般 |
Research Field |
Forest science
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Research Institution | Kyoto University |
Principal Investigator |
NAKANISHI Asami 京都大学, フィールド科学教育研究センター, 助教 (60273497)
|
Co-Investigator(Kenkyū-buntansha) |
INAGAKI Yoshiyuki 森林総合研究所, 立地環境研究領域, 主任研究員 (00353590)
|
Project Period (FY) |
2011 – 2013
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Keywords | 間伐 / 窒素循環 / リターフォール / 堆積有機物 / 土壌養分供給速度 / 下層植生 / スギ / ヒノキ |
Research Abstract |
Nitrogen (N) input by litterfall and N release during decomposition in the organic horizon (O horizon) were evaluated in the sugi and hinoki forests 10 years after thinning. We hypothesized that understory vegetation which has higher N concentration in leaf litter enhances N cycling after thinning. N inputs by litterfall in thinned plots were similar to those in unthinned plots. The effect of thinning on N release in the O horizon was dependent on the amount of O horizon before thinning. In the sites with low accumulation of O horizon, the N release in the O horizon was not affected by thinning. On the other hand, in the sites with high accumulation of O horizon, N release in the O horizon was increased and this increase was partly due to higher input of leaf-litter of understory vegetation. These results suggest that enhancement of N cycling by understory vegetation after thinning is substantial in low-fertility sites and N cycling was not affected by thinning in high-fertility sites.
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