earticle

영어

Regional variations in extreme weather events, such as droughts, is expected to increase and they will have significant impacts on forest ecosystem carbon cycles. In particular, the frequency of spring droughts has been increasing in Korea, and the effects of drought on carbon balance in forests may vary depending on the presence of leaves during spring droughts. In this study, a total of 4 years from 2015 to 2018, net ecosystem production (NEP) of evergreen Korean pine (Pinus koraiensis) and nearby oak dominant deciduous forests were examined using eddy-covariance systems. As a result, the intensity of drought at the study site weakened in the order of 2015, 2017, and 2016, and the drought ended in 2018. In deciduous forests, the annual NEP during the growing season was negatively correlated with the intensity of drought (p-value <0.001, R2 = 0.99) and the recovery index was 1.34 ± 0.13. On the other hand in Korean pine forests, the annual NEP in 2017 was the lowest throughout the study period and the recovery index was 1.16 ± 0.10. This caused by severe drought from the fall of 2016 to the spring of 2017, and during this period, the moisture content of the soil of Korean pine stand was lower than that of deciduous broadleaved forest due to the more evaporation and canopy interception during the winter and early spring. In addition, the recovery of NEP after the drought was slower in Korean pine than deciduous forests due to the legacy effect of extreme moisture stress. Our study could provide useful information for sustainable forest management, especially considering the increase of forest damage caused by climate change including drought.