Effects of thinning on development of understory vegetation and nitrogen utilization of hinoki cypress trees

2016 Fiscal Year Final Research Report

• Project/Area Number: 25450224
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Research Field: Forest science
• Research Institution: Forestry and Forest Products Research Institute
• Principal Investigator: Inagaki Yoshiyuki 国立研究開発法人森林総合研究所, 四国支所, 主任研究員 (00353590)
• Project Period (FY): 2013-04-01 – 2017-03-31
• Keywords: ヒノキ / 下層植生 / 間伐 / 窒素 / 競争 / 安定同位体比

Outline of Final Research Achievements

Thinning in hinoki cypress plantations can develop understory vegetation. Understory vegetation is expected to promote nitrogen cycling of forest ecosystems and enhance nitrogen uptake of hinoki cypress trees. Nitrogen content in leaves of hinoki cypress trees thinned 10 years ago remained lower than that in the unthinned control. Increase of nitrogen uptake by hinoki cypress is not large due to limited increase of leaf biomass.
Nitrogen isotope ratio in leaves was used as an indicator of soil nitrogen sources. Hinoki cypress and understory vegetation utilize similar nitrogen sources in thinned plots while they utilize different sources in the unthinned control. The competition for nitrogen sources between hinoki cypress and understory vegetation was reduced by thinning

Free Research Field

森林生態学