• 研究报告 •

### 增温对亚热带森林土壤可浸提有机碳的影响

1. （福建师范大学地理科学学院, 湿润亚热带山地生态国家重点实验室培育基地(福建师范大学), 福州 350007）
• 出版日期:2020-05-10 发布日期:2020-05-10

### Effects of soil warming on water extractable organic carbon in subtropical forest.

BAI Hao-yu, YANG Zhi-jie*, ZHENG Yong, XIONG De-cheng, ZHOU Jia-cong

1. (College of Geographical Science, Fujian Normal University, State Key Laboratory of Subtropical Mountain Ecology (Funded by Ministry of Science and Technology and Fujian Province), Fujian Normal University, Fuzhou 350007, China).
• Online:2020-05-10 Published:2020-05-10

Abstract: Water extractable organic carbon (WEOC) is sensitive to climate change, and thus plays a vital role in carbon cycling in forest ecosystems. Here, the effects of soil warming (+5 ℃) on soil WEOC extracted by three different methods were examined in a subtropical forest. Concentrations of WEOC extracted by cold water (CWEOC) and salt solution (SWEOC) were not affected by soil warming. Soil warming reduced the concentration of WEOC extracted by hot water (HWEOC) by 51.2% at the 0-10 cm soil layer, but elevated HWEOC by 67.1%, 781.7%, and 501.6%, respectively, at the 10-20, 20-40 and 40-60 cm soil layer. Soil warming increased microbial biomass carbon (MBC) by 98.2% and 163.1% at the 20-40 and 40-60 cm soil later, respectively, but had no effect on MBC at the 0-10 and 10-20 cm. There was a significant difference in soil WEOC concentrations extracted by the three different methods. Generally, the concentration of CWEOC was the lowest among the three extraction methods, and HWEOC and SWEOC were the highest in surface soil layer and deep layer, respectively. The significant effect of soil warming on WEOC could be ascribed to warmingstimulated deeper rooting, which enhance root carbon input and microbial activity in the subsoil and thus induce a decrease of WEOC in the topsoil and an increase of WEOC in the subsoil. Different extraction methods could be used together to reflect different origins and transformations of WEOC. These results could facilitate our understanding of the responses of soil carbon cycling to climate change in subtropical forests.