Spatila-temporal distribution of monohalomethane in the N Pacific

2015 Fiscal Year Final Research Report

• Project/Area Number: 24681001
• Research Category: Grant-in-Aid for Young Scientists (A)
• Allocation Type: Partial Multi-year Fund
• Research Field: Environmental dynamic analysis
• Research Institution: Hokkaido University
• Principal Investigator: Ooki Atsushi 北海道大学, 水産科学研究科(研究院), 准教授 (70450252)
• Project Period (FY): 2012-04-01 – 2016-03-31
• Keywords: 揮発性有機物 / VOC / 有機物分解 / ハロカーボン / 溶存有機物 / 植物プランクトン / 生物地球化学

Outline of Final Research Achievements

Monohalomethanes (chloromethane, bromomethane, and iodomethane) are the dominant organic halogen compounds in the atmosphere. Ocean is an important source of monohalomethane. Spatial-temporal distributions of monohalomethane were measured in the NW Pacific and estern Arctic Ocean. Over the continental shelf of the Chukchi Sea in the Arctic Ocean, the concentration maxima of 3 monohalomethanes were found in the bottom layer water, in which bottom sediment, denitrification would occur owing to a large amount of settling organic particle. In the Funka-Bay, Hokkaido, Japan, concentration maxima of bromomethane and chloromethane were found in the subsurface layer in June when decompositions of organic material proceed. Phytoplankton culture experiment showed that productions of monohalomethane were found in the senescence stage after the exponential growth. It is considered that monohalomethane production in seawater is associated with cell senescence and degradation of organic matter.

Free Research Field

海洋化学