Sydney Institute of Agriculture & School of Life and Environmental Sciences, The University of Sydney, Eveleigh, NSW 2015, Australia; School of Biological, Earth and Environmental Sciences, UNSW Sydney, NSW 2052, Australia.
Sydney Institute of Agriculture & School of Life and Environmental Sciences, The University of Sydney, Eveleigh, NSW 2015, Australia.
Sci Total Environ. 2018 Feb 15;615:540-548. doi: 10.1016/j.scitotenv.2017.09.136. Epub 2017 Oct 6.
Much research has been conducted to understand the spatial distribution of soil carbon stock and its temporal dynamics. However, an agreement has not been reached on whether increasing global temperature has a positive or negative feedback on soil carbon stocks. By analysing global maps of soil organic carbon (SOC) using a spherical wavelet analysis, it was found that the correlation between SOC and soil temperature at the regional scale was negative between 52° N and 40° S parallels and positive beyond this region. This was consistent with a few previous studies and it was assumed that the effect was most likely due to the temperature-dependent SOC formation (photosynthesis) and decomposition (microbial activities and substrate decomposability) processes. The results also suggested that the large SOC stocks distributed in the low-temperature areas might increase under global warming while the small SOC stocks found in the high-temperature areas might decrease accordingly. Although it remains unknown whether the potential increasing soil carbon stocks in the low-temperature areas can offset the loss of carbon stocks in the high-temperature areas, the location- and scale- specific correlations between SOC and temperature should be taken into account for modeling SOC dynamics and SOC sequestration management.
已经进行了大量研究来了解土壤碳储量的空间分布及其时间动态。然而,对于全球气温升高对土壤碳储量是正反馈还是负反馈,尚未达成一致意见。通过使用球形小波分析分析全球土壤有机碳(SOC)图,发现 SOC 与区域尺度上土壤温度之间的相关性在 52° N 和 40° S 平行线之间呈负相关,超出此区域则呈正相关。这与之前的一些研究结果一致,并且人们认为这种影响很可能是由于 SOC 形成(光合作用)和分解(微生物活动和基质可分解性)过程对温度的依赖性所致。研究结果还表明,在全球变暖下,低温地区分布的大量 SOC 储量可能会增加,而高温地区的小 SOC 储量可能会相应减少。尽管尚不清楚低温地区潜在增加的土壤碳储量是否可以抵消高温地区碳储量的损失,但在建模 SOC 动态和 SOC 封存管理时,应考虑 SOC 与温度之间的位置和尺度特定相关性。