Exploring the impact of regional climate and local hydrology on Pinus sylvestris L. growth variability – A comparison between pine populations growing on peat soils and mineral soils in Lithuania

Abstract

Aims: To compare growth variability of Scots pine (Pinus sylvestris L.) on different soil types, and to assess the potential of peat-soil pines for climatological and hydrological studies. Methods: We used extensive dendrochronological analyses to investigate temporal and spatial responses of pines growing on peat soils and mineral soils in three regions of Lithuania. Results: Significant correlations were observed between tree populations growing on similar soil types in different geographical regions, whereas synchronicity was absent between neighbouring stands growing on different soil types. At mineral soils, tree growth was significantly correlated with winter and early summer temperatures, whereas a more complex response was detected in peat-soil trees, presumably reflecting a multi-annual synthesis of moisture variability and changing hydrology. Synchronous long-term peat soil tree-growth variations observed over large parts of the Baltics point to a possible regional hydrological forcing. Our results may therefore improve hydrological reconstructions using living and subfossil peat-soil trees, and could be of prime importance given the major influence peatland water-table fluctuations have on a range of environmental processes. Conclusion: Results reveal that peat-soil pines are unsuitable for high-frequency climate reconstruction, but demonstrate their potential for the reconstruction of multi-annual to decadal hydrological fluctuations. Mineral-soil pines, by contrast, should be used for temperature reconstructions.