Historical Forest Management Practices Influence Tree-Ring Based Climate Reconstructions

Abstract

Tree-ring widths (TRW) of historical and archeological wood provide crucial proxies, frequently used for high-resolution multi-millennial paleoclimate reconstructions. Former growing conditions of the utilized trees, however, are largely unknown. Potential influences of historical forest management practices on climatic information, derived from TRW variability need to be considered but have not been assessed so far. Here, we examined the suitability of TRW series from traditionally managed oak forests (Quercus spp.) for climate reconstructions. We compared the climate signal in TRW chronologies of trees originating from high forests and coppice-with-standards (CWS) forests, a silvicultural management practice widely used in Europe for most of the common era. We expected a less distinct climate control in CWS due to management-induced growth patterns, yet an improved climate-growth relationship with TRW data from conventionally managed high forests. CWS tree rings showed considerably weaker correlations with hydroclimatic variables than non-CWS trees. The greatest potential for hydroclimate reconstructions was found for a large dataset containing both CWS and non-CWS trees, randomly collected from lumber yards, resembling the randomness in sources of historical material. Our results imply that growth patterns induced by management interventions can dampen climate signals in TRW chronologies. However, their impact can be minimized in well replicated, randomly sampled regional chronologies.

Dendroarchaeology in Europe

“…However, it remains uncertain to which extend the climate signal is superimposed by age, siteecological and anthropogenic factors. Since stand conditions of archaeological wood remain unknown, a high annual replication with trees from different sites eliminates non-climate-induced noise from dendroarchaeological tree-ring series (Tegel et al, 2010;Büntgen et al, 2012;Skiadaresis et al, 2021). Moreover, to improve the climate signal of tree-ring chronologies from archaeological wood, several approaches can be applied.…”

Comparing the impact of live-tree versus historic-timber data on palaeoenvironmental inferences in tree-ring science, eastern North America

“…Less attention has been paid to how these data sources inform our understanding of past climate and ecology (but see Bleicher and Staub, 2023; Büntgen et al, 2011; Haneca et al, 2006; Pederson et al, 2014b; Tegel et al, 2010; Thun and Svarva, 2018; Trouet et al, 2017). Dendroarchaeological data are simultaneously touted as potentially unfit for typical tree-ring analyses due to biases and complications related to construction preferences (Black et al, 2008; Copenheaver et al, 2017; de Graauw, 2017; Graauw and Hessl, 2020; Pederson, 2010; Skiadaresis et al, 2021; Trouet et al, 2017) and, conversely, as the only means for building temporally-extended, regional networks of tree-ring data where old-growth forests are scarce (e.g. de Graauw, 2017; Robichaud and Laroque, 2008).…”