刊登于去年Nature上的研究顯示，陸地植物可能是溫室氣體甲烷的來源之一,，這表明植物有可能造成全球甲烷增加,。這個具有富有爭議性的結(jié)果,，引起了一群荷蘭科學(xué)家團體針對這個理論進行重新分析研究。

    在一篇發(fā)表于New Phytologist的文章中,，Tom Dueck和他的同事發(fā)表了他們的研究結(jié)果,，結(jié)論是植物釋放的甲烷量幾乎可以忽略不計，而且對于全球氣候的改變沒有任何影響,。

    這個研究團體結(jié)合了專家及他們設(shè)計的新實驗設(shè)備。植物在這種含有大氣二氧化碳的裝置中生長,，但是其中的碳為同位素碳13,。

    這項設(shè)計使得植物釋放出來的碳可以更容易地偵測到。因此,，如果植物釋放出甲烷,，其中就會含有同位素碳13，而且在空氣中較輕的碳分子背景下能被探測出來,。

    一共有6種植物在這種富含碳13的環(huán)境中生長,，而含有碳13的甲烷的釋放也通過聲光激光技術(shù)測量。這種技術(shù)非常靈敏,，即使是螞蟻呼吸產(chǎn)生的二氧化碳都能測出,。在這樣的先進技術(shù)下，測量到的甲烷值也是接近測量極限,，在統(tǒng)計上而言是接近0的,。這是首次提出的相反測試結(jié)果。

    考慮到植物數(shù)量對結(jié)果的影響,，科學(xué)家又模擬了大量植物生長的情況,，結(jié)果還是發(fā)現(xiàn)產(chǎn)生的甲烷可忽略不計。因此專家認(rèn)為沒有必要再評估植物減輕甲烷量潛力的必要了,，但是對于全球甲烷總量,，還是需要進一步分析。

（編譯/姜欣慧） (資料來源 : biocompare)

英文原文鏈接：

http://news.biocompare.com/newsstory.asp?id=180447

原始出處：

No evidence for substantial aerobic methane emission by terrestrial plants: a 13C-labelling approach

Tom A. Dueck 11Plant Research International, PO Box 16, 6700 AA, Wageningen, the Netherlands; , Ries de Visser 22IsoLife, PO Box 349, 6700 AH, Wageningen, the Netherlands; , Hendrik Poorter 33Plant Ecophysiology, Utrecht University, PO Box 800.84, 3508 TB, Utrecht, the Netherlands; , Stefan Persijn 44Molecular & Laser Physics, Radboud University, Toernooiveld 1, 6525 ED Nijmegen, the Netherlands; , Antonie Gorissen 22IsoLife, PO Box 349, 6700 AH, Wageningen, the Netherlands; , Willem de Visser 11Plant Research International, PO Box 16, 6700 AA, Wageningen, the Netherlands; , Ad Schapendonk 55Plant Dynamics, Englaan 8, 6703 EW, Wageningen, the Netherlands, Jan Verhagen 11Plant Research International, PO Box 16, 6700 AA, Wageningen, the Netherlands; , Jan Snel 11Plant Research International, PO Box 16, 6700 AA, Wageningen, the Netherlands; , Frans J. M. Harren 44Molecular & Laser Physics, Radboud University, Toernooiveld 1, 6525 ED Nijmegen, the Netherlands; , Anthony K. Y. Ngai 44Molecular & Laser Physics, Radboud University, Toernooiveld 1, 6525 ED Nijmegen, the Netherlands; , Francel Verstappen 11Plant Research International, PO Box 16, 6700 AA, Wageningen, the Netherlands; , Harro Bouwmeester 11Plant Research International, PO Box 16, 6700 AA, Wageningen, the Netherlands; , Laurentius A. C. J. Voesenek 33Plant Ecophysiology, Utrecht University, PO Box 800.84, 3508 TB, Utrecht, the Netherlands; and Adrie van der Werf 11Plant Research International, PO Box 16, 6700 AA, Wageningen, the Netherlands;
1Plant Research International, PO Box 16, 6700 AA, Wageningen, the Netherlands; 2IsoLife, PO Box 349, 6700 AH, Wageningen, the Netherlands; 3Plant Ecophysiology, Utrecht University, PO Box 800.84, 3508 TB, Utrecht, the Netherlands; 4Molecular & Laser Physics, Radboud University, Toernooiveld 1, 6525 ED Nijmegen, the Netherlands; 5Plant Dynamics, Englaan 8, 6703 EW, Wageningen, the Netherlands
Author for correspondence:Tom A. Dueck
Tel: +31 317475918
Fax: +31 317423110
Email: [email protected]
Key words : 13C-labelling, climate change, methane emission.

New Phytologist (2007) doi: 10.1111/j.1469-8137.2007.02103.x

No claim to original Dutch government works. Journal compilation © New Phytologist (2007)

Summary

•  The results of a single publication stating that terrestrial plants emit methane has sparked a discussion in several scientific journals, but an independent test has not yet been performed.
 
•  Here it is shown, with the use of the stable isotope 13C and a laser-based measuring technique, that there is no evidence for substantial aerobic methane emission by terrestrial plants, maximally 0.3% (0.4 ng g1 h1) of the previously published values.
 
•  Data presented here indicate that the contribution of terrestrial plants to global methane emission is very small at best.
 
•  Therefore, a revision of carbon sequestration accounting practices based on the earlier reported contribution of methane from terrestrial vegetation is redundant.

Fig. 1 Methane spectra. (a) Spectra calculated from the Hitran database (http://cfa-www.harvard.edu/Hitran/). The arrow indicates the 13C-methane peak used for the measurements. (b) Measured photoacoustic spectrum of laboratory air.

Fig. 2 Long-term steady-state methane emissions by vegetation. (a) Measured 13C-methane emissions (mean ± SE) by a mixture of 13C-enriched plants in the ESPAS (Experimental Soil Plant Atmosphere System) growth chamber under controlled steady-state conditions. Plant biomass increased from 289 (day 0) to 374 (day 6) g dry weight during the experiment (n = 3), and the emissions are given at the median of the time for accumulated emission. (b) Measured (solid line) and predicted (dashed lines) accumulation of methane by 13C-enriched plants in the ESPAS growth chamber. Measured methane concentrations (solid line, closed squares), and methane concentrations predicted from our continuous-flow experiment (Table 3; 21 ng g1 h1, dashed line, open triangles), or from Keppler et al. (2006: ‘sunlight’, 374 ng g1 h1, dot-dashed line, closed diamond; ‘no sun’, 119 ng g1 h1, dotted line, open squares).