Methane emissions by alpine plant communities in the Qinghai–Tibet Plateau

Abstract

using a closed chamber technique. Strong methane emission at the rate of 26.2G1.2 and 7.8G1.1 mg CH 4 m L2 h L1 was observed for a grass community in a Kobresia humilis meadow and a Potentilla fruticosa meadow, respectively. A shrub community in the Potentilla meadow consumed atmospheric methane at the rate of 5.8G1.3 mg CH 4 m L2 h L1 on a regional basis; plants from alpine meadows contribute at least 0.13 Tg CH 4 yr L1 in the Tibetan Plateau. This finding has important implications with regard to the regional methane budget and species-level difference should be considered when assessing methane emissions by plants.

A novel pathway of direct methane production and emission by eukaryotes including plants, animals and fungi: An overview

“…Model results indicated that plant-derived CH 4 emissions contribute 11.83 Tg CH 4 yr À1 over China, with 43% from forests, which account for 24% of the Chinese total CH 4 emissions (Xie et al, 2009). Cao et al (2008) suggested that local plants in alpine meadows account for at least 0.13 Tg CH 4 yr À1 on the Tibetan Plateau. These estimates may be included as potential explanations for the enigma of the recent regional and global CH 4 concentrations (Frankenberg et al, 2005;Heimann, 2011).…”

“…As rates of plant-derived CH 4 vary greatly across plant species in response to environmental stresses (Cao et al, 2008;Qaderi and Reid, 2009;Wang et al, 2009bWang et al, , 2008Wang et al, , 2011aWang et al, , 2011bWatanabe et al, 2012) and no in situ emissions of plant-derived CH 4 have been found, more emission data are needed under both controlled laboratory conditions and field conditions to elucidate the contribution of terrestrial plants to the global CH 4 budget. To the best of our knowledge, only one top-down evaluation has been conducted.…”

“…Early field work did not report enough details about the environmental conditions. We have attempted to provide explanations for potential impacts that may have occurred in some studies (Table S1); for instance, an impact from UV radiation might have occurred at experimental sites with high elevations, thereby affecting the observation of CH 4 emissions (Cao et al, 2008;Mikkelsen et al, 2011). Furthermore, results have shown that CH 4 concentrations are greater in upland forests than in lowland forests (do Carmo et al, 2006;Sinha et al, 2007).…”

“…soil or plant water) and whether plants have their own mechanism(s) to produce CH 4 have been debated (Bruhn et al, 2012;Keppler et al, 2009;Nisbet et al, 2009). Evidence is now accumulating to indicate that plants can produce CH 4 even in the presence of oxygen (Bruggemann et al, 2009;Bruhn et al, 2009Bruhn et al, , 2014Cao et al, 2008;Fraser et al, 2015;Keppler et al, 2008;Lenhart et al, 2014;McLeod et al, 2008;Messenger et al, 2009;Mikkelsen et al, 2011;Reid, 2009, 2011;Sanhueza and Donoso, 2006;Sinha et al, 2007;Vigano et al, 2009Vigano et al, , 2008Wang et al, 2009aWang et al, , 2009bWang et al, , 2011aWatanabe et al, 2012;Wishkerman et al, 2011).…”

Effects of Landuse Change on CH4 Soil-Atmospheric Exchange in Alpine Meadow on the Tibetan Plateau

“…Two small electric fans were used to circulate the chamber air. Gas samples were collected in situ using 100 ml plastic syringes every 10 min over a 30 min period at local time from 09:00-11:00 to represent daily average flux as described by Cao et al [17]. The concentration of CH 4 in the gas samples was analyzed on a gas chromatograph (HP Series 4890D, Hewlett Packard, USA) within two days after sampling.…”