Increased soil emissions of potent greenhouse gases under increased atmospheric CO2
添加于 2011/7/15 11:29:40 1868次阅读 | 1次推荐 | 0个评论
Increasing concentrations of atmospheric carbon dioxide (CO2) can affect biotic and abiotic conditions in soil, such as microbial activity and water content1, 2. In turn, these changes might be expected to alter the production and consumption of the important greenhouse gases nitrous oxide (N2O) and methane (CH4) (refs 2, 3). However, studies on fluxes of N2O and CH4 from soil under increased atmospheric CO2 have not been quantitatively synthesized. Here we show, using meta-analysis, that increased CO2 (ranging from 463 to 780 parts per million by volume) stimulates both N2O emissions from upland soils and CH4 emissions from rice paddies and natural wetlands. Because enhanced greenhouse-gas emissions add to the radiative forcing of terrestrial ecosystems, these emissions are expected to negate at least 16.6 per cent of the climate change mitigation potential previously predicted from an increase in the terrestrial carbon sink under increased atmospheric CO2 concentrations4. Our results therefore suggest that the capacity of land ecosystems to slow climate warming has been overestimated.
Kees Jan van Groenigen; Craig W. Osenberg; Bruce A. Hungate
2011-07-13 第475卷 第7355期 214~216页
地球科学 » 大气科学 » 气候学与气候系统
Environmental science, Earth science, Climate science, Plant sciences