The role of inter-specific, micro-habitat and climatic factors on the carbon isotope (δ13C) variability of a modern leaf assemblage from northern Scandinavia: implications for climate reconstruction

Abstract

BOREAS Loader, N. J. & Rundgren, M. 2006 (May): The role of inter-specific, micro-habitat and climatic factors on the carbon isotope (d 13 C) variability of a modern leaf assemblage from northern Scandinavia: implications for climate reconstruction. Boreas, Vol. 35, pp. 188 Á/201. Oslo. ISSN 0300-9483.To provide a basis for the interpretation of past climatic conditions from Quaternary leaf records, leaf carbon isotope (d 13 C) results are presented for 12 northern European dwarf-shrub, shrub and tree species growing across a network of 18 sites in northern Scandinavia. The role of micro-habitat (hummock/hollow) on carbon isotope trends is explored in addition to a comparison of the carbon isotope composition of both cellulose and wholeleaf material. The data are also examined against local meteorological variables (temperature, precipitation and vapour pressure deficit) at both species and genus levels. Results exhibit only modest coherence between selected plant species and low-order correlations with external climate forcings consistent with accepted models for carbon isotope fractionation. Potential for the analysis and interpretation of stable isotopic time series may still be identified; however, factors such as inter-plant variability, senescence, diagenesis and homogeneity need to be thoroughly addressed before such an approach may be used for palaeoenvironmental reconstructions. These findings highlight the complexities and limitations of spatial calibration methods.

Measurements of hydrogen, oxygen and carbon isotope variability inSphagnummoss along a micro‐topographical gradient in a southern Patagonian peatland

“…This result agrees with plant physiological models and the findings of Loisel et al . (), but runs counter to methane carbon‐source models (Basiliko et al ., ; Raghoebarsing et al ., ; Larmola et al ., ) and some larger‐scale (non‐ Sphagnum ) space‐for‐time transects where it is possible that uncharacterized factors or inter‐site differences may have contributed to the nature of the relationships observed (Ménot and Burns, ; Loader and Rundgren, ; Skrzypek et al ., ; Amesbury et al ., ).…”

“…This provides a range of plant responses across a very wide range of environmental conditions, as might be expected if a single site were monitored over many decades (e.g. Ménot and Burns, ; Ménot‐Combes et al ., ; Loader and Hemming, ; Loader and Rundgren, ; Skrzypek et al ., , ; Amesbury et al ., ).…”

An investigation of the common signal in tree ring stable isotope chronologies at temperate sites

“…Yet, the tree ring isotope archive is not a purely physical archive, but also reflects biological processes. Several studies have observed that the isotope variations in leaves and wood of trees depend on the ecological site conditions, both for carbon and oxygen isotope ratios [ Barbour et al , 2001; Loader and Rundgren , 2006; Wang and Yakir , 1995]. At dry sites, for instance, the carbon isotope ratio may provide more information on precipitation variations than at comparably wet sites, similar to what is known for tree ring width variations [ Leavitt and Long , 1989].…”