Effects of Prescribed Burning on Soil CO2 Emissions from Pinus yunnanensis Forestland in Central Yunnan, China

The effects of low-intensity and high-frequency prescribed burning on the soil CO2 emissions from Pinus yunnanensis forestland should be explored to achieve sustainable operation management under fire disturbance. A Li-6400XT portable photosynthesis meter (equipped with a Li-6400-09 respiration chamber) TRIME®-PICO 64/32 temperature moisture were used measure flux, temperature, at fixed observation sites in two treatments (i.e., unburned (UB) after (AB)) forest Zhaobi Mountain, Xinping County, Yunnan, China March 2019 February 2021. We also determined relationships between flux hydrothermal factors. results showed that (1) both UB AB plots exhibited significant unimodal trend seasonal variations. In 2020, highest fluxes occurred September; they 7.08 μmol CO2·m−2·s−1 morning 7.63 afternoon treatment, which was significantly lower than those treatment (p < 0.05). no differences annual carbon > (2) relationship best fitted by quadratic function, degree fitting 0.435 0.753. an inverted U-shaped correlation plot 0.05) but positive Soil key factor affecting 0.05), while effect this area Therefore, application for hazard reduction region achieved objective without causing persistent drastic increase emissions. could provide important theoretical support scientific implementation burning, as well evaluation ecological environmental burning.