CO2 fluxes from peat in boreal mires under varying temperature and moisture conditions.
CO2 fluxes from peat in boreal mires under varying temperature and moisture conditions.
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DOI：
10.2307/2261357
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发表时间：
1996-04
影响因子：
5.5
通讯作者：
J. Silvola;J. Alm;U. Ahlholm;H. Nykänen;P. Martikainen
中科院分区：
文献类型：
--
作者：
J. Silvola;J. Alm;U. Ahlholm;H. Nykänen;P. Martikainen
1在代表不同营养状态和地下水位的各种沼泽地类型上，在两个季节测量了北方泥炭地的CO2排放。为了研究地下水位下降对CO2通量的长期影响，这些地点还包括25-50年的排水沟。2在原始样地上，以泥炭藓（Spagnum fuscum）为优势种的湿地CO_2通量最低（78- 127mgCO_2m ~（-2）h ~（-1）），在12？CO_2通量最高的是林下植被丰富的湿地（12 ℃时为183- 259mgCO_2·m ~（-2）·h ~（-1））; C，290-340g C02-C m-2年-1）。3.地下水位每下降1cm，12 ℃时CO2通量平均增加7.1mgCOM ~ 2·h ~（-1）; C和9.5g C 〇 2-C m-2年。在某些情况下，沟渠对地下水位的影响，相应地对CO2通量，是小的。然而，有效的排水导致100%的CO2通量增加。排水沟有较高的CO2通量相比，在相同的温度和水位的处女子网站。4温度对CO_2通量的影响取决于地下水位，地下水位0- 20 cm时，QIo平均值为2.9，地下水位低于20 cm时，QIo平均值为2.0。5将CO2通量与初级生产力数据进行了比较，并讨论了泥炭碳储量和气候变化中的碳平衡。
1 Co2 emissions in boreal peatlands were measured during two seasons on various mire site types representing different nutrient statuses and water tables. In order to examine the long term effects of water table draw-down on the CO2 fluxes, the sites also included 25-50-year-old drainages. 2 On virgin sites the lowest CO2 fluxes were measured at ombrotrophic sites dominated by Sphagnum fuscum (78-127mg CO2 m-2 h-' at 12 ?C, 60-200 g CO2-C m-2 year') and the highest CO2 fluxes were at ombrotrophic sites with abundant understorey vegetation (183-259mg CO2 m-2 h-' at 12 ?C, 290-340g C02-C m-2 year-'). 3 Lowering of the water table by 1 cm increased CO2 fluxes by an average of 7.1 mg COM2 h-' at 12 ?C and 9.5 g C02-C m-2 year-'. In some cases the effect of ditches on the water table, and correspondingly on CO2 fluxes, was small. However, effective draining caused 100% increase in CO2 fluxes. Drainages had higher CO2 fluxes compared with virgin subsites at the same temperature and water table. 4 The effect of temperature on CO2 fluxes depended on the water table, the average QIo value being 2.9 with water tables of 0-20cm and 2.0 with water tables below 20cm. 5 CO2 fluxes are compared with primary production figures, and peat carbon stores and the carbon balance in changing climate are discussed.