Ecosystem carbon (CO2 and CH4) fluxes of a Populus dettoides plantation in subtropical China during and post clear-cutting

Abstract

a b s t r a c tPoplar plantations have widely spread around the world due to its high productivity and adaptability. Clear-cutting is the primary harvesting method for poplar plantation management in southern China. However, the effect of harvesting on ecosystem carbon fluxes limits our ability to estimate its carbon sequestration. A consecutive, three-year observation on ecosystem CO 2 and CH 4 flux (F CO2 and F CH4 ) of a Populus dettoides plantation on the floodplain of Yangtze River was made prior and post to the clearcutting using an eddy-covariance system. We found that clear-cutting turned the ecosystem from a strong carbon sink to a mediate carbon source only in several months, July to next January, after the harvest. The ecosystem turned to a net carbon sink at the beginning of the first growing season following clear-cutting due to the large productivity of understory vegetation in this region. The annual carbon budget was À424.3 ± 52.5 g-C m À2 (95% confidence interval) in the harvesting year, with À53.6 ± 22.8 g-C m À2 the first year and À290.7 ± 34.2 g-C m À2 the second year after clear-cutting. Clear-cutting turned the ecosystem from a net CH 4 sink to a net CH 4 source after the third month, but during the three years the CH 4 emission only balanced out a very small portion (0.3%) of F CO2 . In noninundation periods, F CH4 varied from À0.01 to 0.24 mmol m À2 d À1 , with a mean (±SD) of 0.11 ± 0.08 mmol m À2 d À1 , while it ranged from 0.33 to 4.39 mmol m À2 d À1 during inundation, with a mean (±SD) of 2.17 ± 1.16 mmol m À2 d À1 . Daily and weekly F CH4 during non-inundation period were highly correlated with ground water table, soil moisture, and friction velocity, while F CH4 during inundation depended on inundation depth.

Impacts of Clear-Cutting of a Boreal Forest on Carbon Dioxide, Methane and Nitrous Oxide Fluxes

“…Relatively few micrometeorological studies of CH 4 or N 2 O fluxes have been made in forest ecosystems in general [24][25][26][48][49][50][51][52][53]. Zona, Janssens [54] measured CO 2 , CH 4 and N 2 O fluxes above a short-rotation poplar plantation in Belgium, Gao, Chen [55] performed EC measurements of CO 2 and CH 4 in a poplar plantation in subtropical China and Mishurov and Kiely [56] did EC measurements of N 2 O fluxes on afforested grassland. We are not aware of any studies using simultaneous micrometeorological measurements of CO 2 , CH 4 and N 2 O at a clear-cut boreal forest stand.…”

How does management affect soil C sequestration and greenhouse gas fluxes in boreal and temperate forests? – A review

“…Though it was shown that thinning increases soil CO 2 emissions by 29% (Zhang et al, 2018), another study suggests only a 6.8% increase (Yang et al, 2022). However, these two meta-analyses also reported that the responses of soil CO 2 emissions depend on numerous factors including thinning intensity, post-thinning recovery time, stand type, stand age, measurement season, local climate, thinning-induced changes in litterfall, root biomass, soil nutrients, soil microclimate, and soil microbial community composition and activities (Adamczyk et al, 2015;Gao et al, 2015;Hao et al, 2019;Keller et al, 2005;Zhang et al, 2018).…”

Editing Metabolism, Sex, and Microbiome: How Can We Help Poplar Resist Pathogens?

“…One reason for this is that poplar has a high biomass accumulation rate [4] and is, therefore, used for the production of paper and wood products [5,6]. It is also increasingly used in green energy as it can be utilized to produce biofuels [7][8][9][10] and CO2 absorption to combat climate change [11,12]. In a number of cities around the world, it is used for urban landscaping [13,14], and its high resistance to heavy-metal pollution allows for it to be used for the phytoremediation of soils [15][16][17].…”