Abstract

Authors

YASUDA Yukio, SAITO Takeshi, HOSHINO Daisuke, ONO Kenji, OHTANI Yoshikazu, MIZOGUCHI Yasuko, MORISAWA Takeshi

Year

2012

Title

Carbon balance in a cool-temperate deciduous forest in northern Japan: seasonal and interannual variations, and environmental controls of its annual balance.

Journal

Journal of Forest Research

Volume

TBD

Page

TBD

DOI

doi:10.1007/s10310-011-0298-x

Keywords

Beech forest, Eddy covariance, Environmental control, Interannual variation, Net ecosystem production

URL

http://www.springerlink.com/content/b655913862731614/

Abstract

We monitored variation in seasonal and annual net ecosystem production (NEP), gross primary production (GPP), and ecosystem respiration (R E) based on 7-year eddy covariance measurements above a cool temperate deciduous broad-leaved forest (Japanese beech forest). The 7-year means (}SD) of annual NEP, GPP, and R E were 312 } 64, 1250 } 62, and 938 } 36 g C m-2 year-1, respectively. Variation in NEP was much larger than variation in GPP and R E. During the growing season, the main factor controlling carbon balance was air temperature; variation in seasonal integrated NEP was regulated by accumulated air temperature (degree-day) with a significant negative correlation, whereas the seasonal ratio of R E to GPP was correlated positively with accumulated air temperature. Because the deviation of seasonal NEP was also significantly correlated with seasonal R E/GPP, NEP was controlled by R E/GPP, depending on air temperature during the growing season. Seasonal R E in the defoliation and snow seasons was also important for evaluating the annual carbon balance, because the total number of days in the two seasons was quite large owing to a long snowy winter. In the defoliation and snow seasons, we found defoliation season length was a major factor determining seasonal integrated R E, illustrating the positive correlation between R E and defoliation season length. The major factors controlling interannual variations in forest carbon balance are discussed.

Site

API

Remarks

online first