Influence of organic matter of forest floor on radioactive cesium movement, accumulation and outflow in the small watersheds.

2017 Fiscal Year Final Research Report

• Project/Area Number: 15H04511
• Research Category: Grant-in-Aid for Scientific Research (B)
• Allocation Type: Single-year Grants
• Section: 一般
• Research Field: Forest science
• Research Institution: Tokyo University of Agriculture and Technology
• Principal Investigator: Toda Hiroto 東京農工大学, (連合)農学研究科(研究院), 教授 (00237091)
• Co-Investigator(Kenkyū-buntansha): 崔 東壽 東京農工大学, (連合)農学研究科(研究院), 准教授 (20451982) ; 五味 高志 東京農工大学, (連合)農学研究科(研究院), 教授 (30378921) ; 吉田 智弘 東京農工大学, 農学部, 講師 (60521052)
• Project Period (FY): 2015-04-01 – 2018-03-31
• Keywords: 有機物分解 / 土壌有機物 / モル型土壌 / ムル型土壌 / 渓流生態系 / 外生菌根菌 / ナラ林 / 萌芽更新

Outline of Final Research Achievements

The movement of radioactive cesium (Cs-137) in forest ecosystems were investigated. In particular, the investigation was focused on the organic layer of forest floor. In the mull type, where the decomposition rate of the organic layer is fast and thin, there was high migration rate of Cs-137 to the mineral soil. In the mor type, where the organic layer is thick, there was much accumulation of Cs-137 in the organic layer. There was a lot of fine root of oak in the organic layer of the mor type, and Cs-137 concentration of oak tree at the mor type was greater than at the mull type. There was a negative correlation between the soil C/N and Cs-137 concentration, and a positive correlation between the abundance ration of soil carbon and Cs-137. These results suggested that the forest floor type, namely the decomposition rate of organic layer, influenced Cs-137 movement. In future, in order to use the forest, we have to research to clarify Cs-137 cycle of the forest ecosystems.

Free Research Field

森林立地学、森林生態学