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article i nfo Article history: Testate amoeba analyses were realized to reconstruct Holocene hydroclimatic variations and carbon accumula- tion from two peat cores collected in a permafrost peatland located at the southern limit of the discontinuous permafrost zone near Kuujjuarapik, subarctic Quebec, Canada (55°13'N, 77°41'W). Results from the central core show synchronic changes with lake level variations from northeastern Quebec. Palsa aggradation has been identified from 660 to 140 cal. BP with changes in testate amoeba assemblages, reconstructed surface dryness and strongly decomposed peat. Our results also show that low carbon accumulation rates (9.5 g·m − 2 ·yr − 1 and 8.6 g·m − 2 ·yr − 1 ) are linked to colder periods that may be associated with solar minima (AD 1460-1550 and AD 1645-1715). Recent warming of the last decades shows an important return to peat accumulation following permafrost degradation in the region. |
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