Establishment of a plantation system for salt and waterlogging damage control using salt-tolerant transpiration-promoting tree species and abandoned farmland

• Project/Area Number: 16H02764
• Research Category: Grant-in-Aid for Scientific Research (A)
• Allocation Type: Single-year Grants
• Section: 海外学術
• Research Field: Rural environmental engineering/Planning
• Research Institution: Tokyo University of Technology
• Principal Investigator: Egashira Yasuyuki 東京工科大学, 工学部, 教授 (70223633)
• Co-Investigator(Kenkyū-buntansha): 酒井 裕司 工学院大学, 先進工学部, 准教授 (40361513) ; 高橋 伸英 信州大学, 学術研究院繊維学系, 教授 (40377651) ; 菅沼 秀樹 信州大学, 繊維学部, 特任助教 (90447235)
• Project Period (FY): 2016-04-01 – 2021-03-31
• Project Status: Completed (Fiscal Year 2022)
• Budget Amount: ¥41,210,000 (Direct Cost: ¥31,700,000、Indirect Cost: ¥9,510,000); Fiscal Year 2020: ¥6,240,000 (Direct Cost: ¥4,800,000、Indirect Cost: ¥1,440,000); Fiscal Year 2019: ¥8,190,000 (Direct Cost: ¥6,300,000、Indirect Cost: ¥1,890,000); Fiscal Year 2018: ¥5,850,000 (Direct Cost: ¥4,500,000、Indirect Cost: ¥1,350,000); Fiscal Year 2017: ¥12,870,000 (Direct Cost: ¥9,900,000、Indirect Cost: ¥2,970,000); Fiscal Year 2016: ¥8,060,000 (Direct Cost: ¥6,200,000、Indirect Cost: ¥1,860,000)
• Keywords: 耐塩性樹種 / 塩害対策植林 / 湛水害対策植林 / 蒸散速度 / 蒸散速 / 環境技術 / 塩害 / 植林システム / 湛水害

Outline of Final Research Achievements

The feasibility of planting salt-tolerant transpiration-accelerating tree species on abandoned farmland where salt and waterlogging damage has occurred was examined with a view to addressing the salt and waterlogging damage caused by groundwater imbalance resulting from deforestation in Western Australia.
All the tree species showed high establishment rates in the test afforestation sites established in the abandoned farmland.Changes in transpiration in abandoned farmland with salinity in the soil were investigated by long-term measurements using sap flow sensors.We also studied the groundwater level around the salt lake-like area in the valley of the farmland, and found that the water level in the surrounding groundwater basin was higher than that in the salt lake-like area.This suggests that the area of abandoned farmland is determined by the dynamic balance between upwelling and evapotranspiration.

Academic Significance and Societal Importance of the Research Achievements

西オーストラリアでの森林伐採に起因する地下水アンバランスが原因となった塩害・湛水害への対策として農耕地内に植林を行うことが有効であることは既に明らかになっているが、一部とはいえ農耕地を潰して植林を行う、という行為への抵抗感は依然として大きい。すでに耕作を放棄した場所への植林であれば受け入れやすいが、そのような土地でも植林可能な樹種がある、ということは実証的に示される必要がある。
本研究では耐塩性蒸散促進樹種の生理的な特性と並んで、比較的規模の大きな耕作放棄地への植林を行うことで、有効性の実証のスタート地点に立つことができた。

Research Products

• [Journal Article] Estimation of CO2 sequestration potential by afforestation in the arid rangelands of Western Australia based on long-term empirical data (2019)
  • Author(s): Suganuma Hideki、Aikawa Shin-ichi、Sakai Yuji、Hamano Hiroyuki、Takahashi Nobuhide、Tahara Kiyotaka、Kawarasaki Satoko、Utsugi Hajime、Egashira Yasuyuki、Kawanishi Takuya、Harper Richard J.、Tanouchi Hiroyuki、Kojima Toshinori、Abe Yukuo、Saito Masahiro、Kato Shigeru、Law John、Yamada Koichi
  • Journal Title: Ecological Engineering Volume: 133 Pages: 109-120
  • DOI: 10.1016/j.ecoleng.2019.04.015
  • Peer Reviewed
• [Presentation] Technology for Maintain Ground Waterbalance to Avoid Water Logging and Salt Accumulation in Western Australia Croplands by Utilization of Salt Tolerant Tree Species (2019)
  • Author(s): Yasuyuki Egashira et.al.
  • Organizer: 18th Asian Pacific Confederation of Chemical Engineering (APCChE)
  • Int'l Joint Research