An appropriate time-window for measuring soil CO2 efflux: a case study on a Black soil in north-east China |
| |
| Authors: | Xiuhuan Shi Xiaoping Zhang Xueming Yang Neil B. McLaughlin Aizhen Liang Ruqin Fan |
| |
| Affiliation: | 1. Northeast Institute of Geography &2. Agroecology, Chinese Academy of Sciences , Changchun , 130012 , China;3. Department of Resources &4. Environment , Graduate School of the Chinese Academy of Sciences , Beijing , 100049 , China;5. Greenhouse &6. Processing Crops Research Centre, Agriculture &7. Agri-Food Canada , Harrow , ON N0R 1G0 , Canada shixiuhuan@hotmail.com;9. Agroecology, Chinese Academy of Sciences , Changchun , 130012 , China;10. Greenhouse &11. Agri-Food Canada , Harrow , ON N0R 1G0 , Canada;12. Eastern Cereal and Oilseed Research Centre, Agriculture &13. Agri-Food Canada , Ottawa , ON K1A 0C6 , Canada;14. Environment , Graduate School of the Chinese Academy of Sciences , Beijing , 100049 , China |
| |
| Abstract: | Abstract Soil CO2 efflux rate is influenced by soil temperature which varies with time within a day. In order to determine a measuring time-window which can represent the daily average soil CO2 efflux rate from a Black soil in north-east China, soil CO2 efflux rates from no-tillage (NT) and mouldboard plough tillage (MP) plots were measured at a 2-h interval over 48 h four times in the growing season of 2008. Results showed that during the course of measurements, NT soil had a higher soil CO2 efflux rate than MP soil. Daily average soil CO2 efflux rate was matched relatively well with the CO2 efflux rate occurring between 09:00 h and 13:00 h, and between 19:00 h and 23:00 h. Our results indicate that the soil CO2 efflux rate measured between 09:00 and 11:00 h represents the daily average soil CO2 efflux rate during sunny days. When the measurements were conducted outside this time window, a procedure to adjust the CO2 efflux rates measured between 07:00 and 21:00 h (outside of the optimum time-window) to estimate daily average soil CO2 efflux rate is described. |
| |
| Keywords: | Black soil no-tillage soil CO2 efflux time models time-window |
|
|
