[Effects of climate warming on the N2O emission from Larix gmelinii forest soils at different latitudes during soil thawing period].
During the soil thawing period in spring, large amount of N2O was emitted from the forest soils in North China, being a major source of atmospheric greenhouse gases. However, the contribution of the emitted N2O and its responses to climatic change are unclear. In this paper, sampling plots of Larix gmelinii forest (including sapling, ground vegetation, and soil A and B horizons) with similar stand conditions in Tahe (52 degrees 31' N), Songling (50 degrees 43' N), Sunwu (49 degrees 13' N), and Dailing (47 degrees 05' N) were displaced to the south boundary of L. gmelinii natural distribution area to simulate that the plots were under climate warming, and their N2O fluxes were measured during the soil thawing period in spring 2007. For the four plots, the N2O fluxes all peaked at the mid- or late stage of soil thawing. The N2O flux of the plots from Dailing, Suwu, Songling, and Tahe during soil thawing period was averagely 66.5 +/- 9.3, 54.3 +/- 5.6, 44.3 +/- 5.3, and 33.5 +/- 3.7 microg x m(-2) h(-1), respectively, and significantly positively correlated to the soil temperature at 5 cm depth and the soil microbial biomass carbon at 0-10 cm depth. No significant relationship was observed between the N2O flux and soil moisture content. The soil N2O emission during soil thawing period differed significantly among the plots. Both the mean N2O flux and the cumulative N2O emission decreased with increasing latitude, mainly due to the differences in soil microbial activities and soil physical properties.
Fu
Min-Jie
MJ
College of Forestry, Northeast Forestry University, Harbin 150040, China. fuminjie@163.com
Wang
Chuan-Kuan
CK
Wang
Ying
Y
Liu
Shi
S
Ding
Shuang
S
D000393:Air Pollutants / Q000032:analysis*; D002681:China; D017753:Ecosystem; D004784:Environmental Monitoring; D005843:Geography; D057232:Global Warming; D028221:Larix / Q000254:growth & development*; D009609:Nitrous Oxide / Q000032:analysis / Q000378:metabolism*; D012621:Seasons; D012987:Soil / Q000032:analysis*
D000393:Air Pollutants; D012987:Soil; D009609:Nitrous Oxide