Earthquakes Have Accelerated the Carbon Dioxide Emission Rate of Soils on the Qinghai-Tibet Plateau.

The Qinghai-Tibet Plateau (QTP) has an extensive frozen soil distribution and intense geological tectonic activity. Our surveys reveal that Qinghai-Tibet Plateau earthquakes can not only damage infrastructure but also significantly impact carbon dioxide emissions. Fissures created by earthquakes expose deep, frozen soils to the air and, in turn, accelerate soil carbon emissions. We measured average soil carbon emission rates of 968.53 g CO2 m-2·a-1 on the fissure sidewall and 514.79 g CO2 m-2·a-1 at the fissure bottom. We estimated that the total soil carbon emission flux from fissures caused by M ≥ 6.9 earthquakes on the Qinghai-Tibet Plateau from 326 B.C. to 2022 is 1.83 × 1012 g CO2 a-1; this value is equivalent to 0.51% ~ 1.48% and 2.34% ~ 5.14% of the increased annual average carbon sink resulting from the national ecological restoration projects targeting forest protection and grassland conservation in China, respectively. These earthquake fissures thus increased the soil carbon emission rate by 0.71 g CO2 m-2·a-1 and significantly increased the total carbon emissions. This finding shows that repairing earthquake fissures could play a very important role in coping with global climate change.