Journal
ECOLOGICAL RESEARCH
Volume 24, Issue 4, Pages 865-871Publisher
SPRINGER TOKYO
DOI: 10.1007/s11284-008-0560-7
Keywords
Root respiration; Midday-depression; Soil respiration; Carbon cycling; NEP
Categories
Funding
- Takesige Bekku
- Tosiko Bekku
- Global Environment Research Fund [S-02-01]
- Ministry of Education, Science, and Culture, Japan [19570025]
- Grants-in-Aid for Scientific Research [19570025] Funding Source: KAKEN
Ask authors/readers for more resources
We observed the phenomenon of midday depression in the rate of tree root respiration. Diurnal changes in the root respiration rate of Quercus crispula and Chamaecyparis obtusa were measured under intact conditions using a closed chamber method and a soil respiration measurement system (LI-6400 with a root respiration chamber) in a forest in the foothills of Mt. Fuji. After the measurement of intact root respiration in the field, the root was excised and taken to the laboratory, and the temperature dependence on the respiration rate of the detached root was measured using an open-flow gas exchange system with an infrared gas analyzer (LI-6252). The measurement was conducted in September 2003, August and November 2005, and June 2006. Whereas the root respiration rate of both species under intact conditions increased with increasing soil and root temperatures from dawn to early morning, the respiration rate decreased around midday from 10:00 to 15:00 despite an increment of soil and root temperatures. There was no clear relationship between the intact root respiration rate and root temperature in either species, although the detached root respiration rate of both increased exponentially with the temperature. The amount of the CO(2) efflux estimated using the temperature dependence of detached root respiration tended to underestimate the actual measurement value (intact respiration rate) by 20-50% in both species. These results indicate that evaluating midday depression in root respiration would be important for a more accurate estimation of the carbon cycle or net ecosystem production in forests.
Authors
I am an author on this paper
Click your name to claim this paper and add it to your profile.
Reviews
Recommended
No Data Available