Increasing radial and latewood growth rates of Larix cajanderi Mayr. and Pinus sylvestris L. in the continuous permafrost zone in Central Yakutia (Russia)
Study area and comparison of mean yearly temperature and total yearly precipitation among sampling sites. The meteorological data covers the
common period 1966–2015 and was from 0.5°-resolution CRU grids
Annual radial growth and latewood formation increase during the period 1966–2015 in Larix cajanderi Mayr. and Pinus sylvestris L. along a latitudinal gradient on Siberian permafrost. Warmer temperatures and precipitation at the onset of the growth season favor growth in both species.
Context A vast area of Siberian boreal forest is covered by continuous permafrost, where tree radial growth is strongly limited by low temperatures. Understanding how climate controls Siberian conifer growth is critical in order to predict their response to ongoing climate change.
Aims To explore variations in the radial growth and earlywood/latewood formation of Pinus sylvestris L. and Larix cajanderi Mayr. trees along a climate gradient within the continuous permafrost zone in Central Yakutia (Russia), a region experiencing accelerated warming.
Methods We evaluated spatiotemporal differences in tree-ring and latewood width among sites by using generalized additive mixed models. Pearson’s correlations were used to analyze the effect of local climate (temperature, precipitation) and drought (SPEI) on the formation of earlywood and latewood.
Results Both conifers showed increased radial growth in recent decades. Radial growth was controlled by temperature and precipitation in both species along the gradient, with earlier precipitation events being critical for the formation of wide rings.
Conclusion Although temperature is considered as the main limiting factor triggering tree growth in the continuous permafrost zone, our results showed that water availability also plays a key role in radial tree growth even in the coldest sites.
Keywords
Central Yakutia, Climate, General additive mixed models, Pointer years, SPEI, Tree growth
Publication
Arzac, A., Popkova, M., Anarbekova, A. et al. Annals of Forest Science (2019) 76: 96. https://doi.org/10.1007/s13595-019-0881-4
For the read-only version of the full text: https://rdcu.be/bU70K
Data availability
The datasets generated and/or analyzed during the current study are available in the Harvard Dataverse repository (Arzac et al. 2019) at https://doi.org/10.7910/DVN/BWIFOX
