The influence of drought intensity on soil respiration during and after multiple drying-rewetting cycles

Publication date: Available online 21 September 2018Source: Soil Biology and BiochemistryAuthor(s): Jin-Tao Li, Jun-Jian Wang, De-Hui Zeng, Shan-Yu Zhao, Wan-Ling Huang, Xue-Kai Sun, Ya-Lin HuAbstractGlobal climate change is projected to intensify soil drying-rewetting (DRW) events with extended drought, especially in arid and semiarid ecosystems. However, the extent to which the soil DRW with intensified drought can alter soil respiration (Rs) in forests is still under debate, and subsequent legacy effects on Rs are not well understood. Here, we conducted a 180-d soil incubation experiment to investigate how soil DRW with different drought intensities alter the Rs in poplar (Populus simonii) and Mongolian pine (Pinus sylvestris var. mongolica) plantations. The incubation experiment included four 30-d cycles of 1) constant moisture treatment (control), 2) DRW with 10-d drying and 20-d rewetting (DRW10-20) or 3) DRW with 20-d drying and 10-d rewetting (DRW20-10), and then an extend 60-d incubation under constant moisture. During the four DRW cycles, the direct C release with respiration of Mongolian pine soils (27 g C·m−2 in DRW10-20 and 140 g C·m−2 in DRW20-10, respectively) decreased to a much lower extent than that of poplar soils (228 g C·m−2 in DRW10-20 and 498 g C·m−2 in DRW20-10, respectively). Rs did not significantly change during the extended 60-d incubation in the DRW10-20 treatment compared to control treatment. However, the respired CO2...
Source: Soil Biology and Biochemistry - Category: Biology Source Type: research