Abstract

Authors

MIZOGUCHI Y., OHTANI Y., WATANABE T., YASUDA Y., OKANO M.

Year

2003

Title

自動開閉型チャンバを用いた林床面からのCO₂放出速度の長期連続測定
Long term continuous measurement of CO₂ efflux from a forest floor using dynamic closed chambers with automatic opening/closing capability

Journal

日本生態学会誌(Japanese Journal of Ecology)

Volume

53(1)

Page

1-12

DOI

-

Keywords

Automatic opening, closing chamber, Continuous measurement, Soil CO₂ efflux, Soil temperature, Soil water content

URL

http://ci.nii.ac.jp/naid/110001878116/

Abstract

Soil CO₂ efflux was continuously measured in a deciduous forest for one year using two dynamic closed chambers whose tops were automatically opened after the measurements. Our measurement system decreased differences in environmental conditions between the inside and outside of the chambers. Changes in soil temperature at 0 cm and 2 cm depth were similar inside and outside the two chambers. Changes in soil CO₂ efflux showed two peaks on a non-rainy day in summer, although changes in soil temperature at depths of 0, 2, 5, 10, 25 and 50 cm showed only one peak during the same day. The relationship between the daily mean soil temperature at each depth and soil CO₂ efflux was well represented by an exponential function, while the fluctuations of soil CO₂ efflux were less well explained by soil temperature at 50 cm depth than at 0-25 cm depth. This suggests that the vertical distributions of soil temperature and CO₂ sources, such as soil microbes and plant roots, could affect soil CO₂ efflux. Soil water content also affected soil CO₂ efflux. The decreased soil CO₂ efflux in summer coincided with a decreased soil water content. However, a decrease in soil CO₂ efflux was observed at the onset of rainfall. This suggests the need to consider the effects of soil water content on both the response of CO₂ sources and the diffusion coefficient of CO₂ in the soil.

Site

KWG

Remarks

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