Soil condition for tree growing at urban area

2023 Fiscal Year Final Research Report

• Project/Area Number: 19K06114
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Review Section: Basic Section 39070:Landscape science-related
• Research Institution: Tokyo University of Agriculture
• Principal Investigator: SUZUKI KOJIRO 東京農業大学, 地域環境科学部, 教授 (80256643)
• Co-Investigator(Kenkyū-buntansha): 金澤 弓子 東京農業大学, 地域環境科学部, 准教授 (50572517)
• Project Period (FY): 2019-04-01 – 2024-03-31
• Keywords: 造園 / 巨木 / 樹木医 / 地形 / シイノキ / 土壌の物理性 / 土壌の化学性 / 災害

Outline of Final Research Achievements

Assuming environmental differences (particularly soil conditions) between urban green spaces and suburban green spaces (mixed conifer-broadleaf forests such as satoyama), we investigated soil factors (physical properties and topography) that affect plant growth. We focused on Castanopsis sieboldii and C.cuspidata and their hybrids, which were once widely used as firewood and charcoal and are found in abundance in the southern Japan. Field survery and experiments were conducted to investigated the geographical conditions under which Castanops grows and to examine the effects of underground stagnation on Castanopsis growth . As a result, we clarified the distribution characteristics of Castanopsis trees, which is widely distributed in mountainous areas west of central Tokyo, the topographical conditions of the habitats of giant Castanopsis trees found in the southern Japan, and the characteristic of Castanopsis trees that have not tolerant to stagnation.

Free Research Field

造園学

Academic Significance and Societal Importance of the Research Achievements

都市をはじめとして，それぞれの地域で緑地を守ることは，大きな社会的課題である。緑地を構成する主要素材は，土と植物である。環境要因としての都市における土壌条件は極めて劣悪であり，未解明な問題が多い。都市の土壌に特有の物理性や化学性，生物性の違いとも大きく関連する地形等についても不明な点が多い。本研究の成果として得たシイノキが生育する地形の特徴や，土壌の物理性（特に気相率が下がる地下部の滞水耐性）に対する特徴は，都市で樹木を保全するため，また都市公園や街路樹などでの植栽管理，都市の生物多様性の向上のための基礎的知見となる。