As the climate warms, the frequency and area of fires are increasing, which in turn changes the composition of the atmosphere and the terrestrial carbon cycle by affecting the carbon budget. Soil carbon release responds inconsistently to fires across ecosystem types. There is also great uncertainty about the impact of time after a fire on soil carbon release. In addition, there is still a lack of direct field experimental evidence on how fires combined with nitrogen addition affect soil carbon release.
In this study, the above questions were analyzed and answered by setting up fire and nitrogen addition control experiments in coniferous and broad-mixed forests in the subtropical-warm temperate climate transition zone of China, combined with the integrated analysis of the impact of fire on global forest soil carbon release. The results of field control experiments showed that fire significantly increased soil respiration, while nitrogen addition had no effect on soil respiration. The increase in soil respiration after the fire increased year by year, which was related to the change of soil temperature and the inter-annual change of woody tree species cover. Conversely, the global meta-analysis showed that forest soil respiration did not change significantly within 1-3 years after the fire, and only negative effects were observed in subtropical forests. This study highlights that general patterns revealed by global integration analysis may not predict the response of ecosystems to environmental change in a particular location.
On July 15, 2020, the research results were published in the classic journal "Agricultural and" in the field of ecology under the title "Understanding the effects of fire and nitrogen addition on soil respiration of a field study by combining observations with a meta-analysis" Published in Forest Meteorology. Agricultural and Forest Meteorology is an international mainstream journal of ecology published by Elsevier Publishing House in the United States. The journal is divided into a region by the SCI division of the Chinese Academy of Sciences, with a 2020 impact factor of 4.651.