Abstract:
:The boreal forests, identified as a critical "tipping element" of the Earth's climate system, play a critical role in the global carbon budget. Recent findings have suggested that terrestrial carbon sinks in northern high-latitude regions are weakening, but there has been little observational evidence to support the idea of a reduction of carbon sinks in northern terrestrial ecosystems. Here, we estimated changes in the biomass carbon sink of natural stands throughout Canada's boreal forests using data from long-term forest permanent sampling plots. We found that in recent decades, the rate of biomass change decreased significantly in western Canada (Alberta, Saskatchewan, and Manitoba), but there was no significant trend for eastern Canada (Ontario and Quebec). Our results revealed that recent climate change, and especially drought-induced water stress, is the dominant cause of the observed reduction in the biomass carbon sink, suggesting that western Canada's boreal forests may become net carbon sources if the climate change-induced droughts continue to intensify.
journal_name
Proc Natl Acad Sci U S Aauthors
Ma Z,Peng C,Zhu Q,Chen H,Yu G,Li W,Zhou X,Wang W,Zhang Wdoi
10.1073/pnas.1111576109subject
Has Abstractpub_date
2012-02-14 00:00:00pages
2423-7issue
7eissn
0027-8424issn
1091-6490pii
1111576109journal_volume
109pub_type
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