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中亚热带植物排放甲烷研究初报 总被引:1,自引:0,他引:1
甲烷(CH4)是大气中第二大温室气体,近年有研究发现在有氧条件下陆生植物也能排放CH4.本研究对中亚热带51种树木离体叶片在有氧环境下进行室内培养,发现21种植物能排放CH4,CH4排放速率范围为0.11~1.37 ngCH4.g-1 DW.h-1,平均排放速率为0.59ngCH4.g-1DW.h-1.植物是否排放CH4及其排放速率与观测条件密切相关.观测的51种植物中包括40种乔木树种和11种灌木树种,分别有15种和6种植物可排放CH4,CH4平均排放速率分别为0.69 CH4.g-1DW.h-1和0.30 ngCH4.g-1DW.h-1,且乔木和灌木之间存在极显著差异(P<0.05). 相似文献
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TheUBV light curves obtained by Duerbeck (1975) andHa (wide) and Ha (narrow) light curves obtained by Chambliss & Davan (1987) of the detached eclipsing binary VV Orionis (VV
Ori) were analysed using the Wilson-Devinney method fixing the two parametersT
h (25,000 K) and q(0.4172), resulting in the following absolute elements:A = 13.605 ± 0.03 LR⊙,R
h = 5.03 ±0.03R
⊙, Rc = 2.43 ±0.02R
⊙,M
bol,h
= -5.18 ± 0.11,M
bol,c
= -1.54 ± 0.06,m
h
=10.81 + 0.42m
⊙ andm
c
= 4.51 ± 0.41m
⊙. The de-reddened colours obtained from applying the reddening corrections ofE(B-V) = 0m.05 andE(U-B) = O
m
.04, and the derived temperatures of the components, gave spectral types ofB 1.5V for the primary and 54-5V with anUV excess of 0
m
·3 for the secondary component. A comparison of the logL and logT
e of the components with the observed ZAMS shows the primary component to be a little above and the secondary component to
be a little below/or on the ZAMS. A comparison of the properties of the components of VV Ori and a few other detached systems
with the normal stars in the logL, logR and logT
e versus logm planes, indicated a need for either a readjustment of the scales of the above parameters or modifications in the theoretical
models. From the position of the components on the evolutionary tracks of Pop I composition computed by Schaller et al. (1992)
it is noticed that while the primary component of W Ori had slightly evolved along the main-sequence, its secondary is still
unevolved. The age of VV Ori is found to be 10 ± 1 million years and it is at a distance of 368 ± 10 pc. 相似文献
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