Comparison of soil respiration among three different subalpine ecosystems on eastern Tibetan Plateau, China

Abstract

The pattern of soil respiration and its responsible factors are still unclear in subalpine ecosystems. In this study, we used a static chamber system to measure soil respiration in a primary Abies fabri (Masters) Craib forest, a secondary A. fabri forest and a clear-cut land on Gongga Mountain, east of Tibetan Plateau in China. Our results showed there were substantial diurnal and temporal variations in these three subalpine ecosystems. The diurnal coefficient of variation (CV) of soil respiration was lowest in primary forest (20.5%), and highest in clear-cut land (40.4%). Diurnal patterns of soil respiration were generally associated with soil temperature at 5 cm for all the three systems. The temporal CV was lowest in secondary forest (55.6%), and highest in clear-cut land (82.8%). Soil temperature at 5 cm depth was the major factor controlling 55-61% of temporal variation of soil respiration. The temperature sensitivity (Q10 value) was higher in clear-cut land (Q10 = 6.7) than that in primary forest (3.7) and secondary forest (3.0), indicating that soil respiration in clear-cut land was more sensitive to temperature change. Annual soil respiration was 3330.2 g carbon dioxide (CO 2 ) m −2 year −1, 2358.9 g CO 2 m −2 year −1 and 4162.8 g CO 2 m −2 year −1 for primary forest, secondary forest and clear-cut land, respectively. Our findings provided valuable information for understanding the effect of forest ecosystem change and land management on soil respiration in highelevation subalpine ecosystems.

Soil respiration and its environmental response varies by day/night and by growing/dormant season in a subalpine forest

“…Moreover, higher daytime R S rates may result from greater translocation of high photosynthesis from the plant shoots to the roots during the daytime relative to at nighttime. The differences in the content and quality of SOC were also reported to determine high and low R S in previous studies272829.…”

Different responses of soil respiration to climate change in permafrost and non‐permafrost regions of the Tibetan plateau from 1979 to 2018

“…Because of the lack of long-term and large-scale soil respiration observation data, we synthesized the results of 53 soil respiration measurements from published journal articles (Geng et al, 2012;Lu et al, 2013;Pang et al, 2013;Chen et al, 2014;Liu et al, 2015;Li et al, 2017Li et al, , 2019Ma et al, 2018;Wang et al, 2018Wang et al, , 2020Duan et al, 2019;Sun et al, 2019). Most of these measurements included soil respiration results for the growing season.…”

Depth heterogeneity of soil organic carbon dynamics in a heavily grazed alpine meadow on the northeastern Tibetan Plateau: A radiocarbon-based approach

“…Vegetation map of the Tibetan Plateau [ Editorial Board of Vegetation Map of China , ] and locations of sampling sites in our and other studies. Filled squares denote sites at which soil respiration was measured using the chamber method for different land cover: alpine meadows [ Cao et al , ; Zhang et al , ; Wang et al , ; Zhang et al , ; Li and Sun , ; Geng et al , ; Wang and Wu , ; Wang et al , ; Zong et al , ; Li et al , ], alpine steppes [ Zhang et al , ; Geng et al , ; Wei et al , ; Lu et al , ; Li et al , ], alpine forests [ Xu et al , ; Chen et al , ], and alpine deserts [ Li et al , ]. Filled circles indicate sites at which soil respiration was inferred from 14 C measurements in this study and others [ Wang et al , ; Tao et al , ].…”