Leaf wax n-alkanes in leaves, litter, and surface soil in a low diversity, temperate deciduous angiosperm forest, Central Missouri, USA.

Stout, Scott A.

The leaf wax n-alkanes in modern ecosystems serve as proxies for assessing the ecologic and climatic conditions in soils, sediments and other geologic archives, and potentially as baselines for future ecological changes. In this study, the concentrations and distributions of long-chain (C25-C35) n-alkanes in fresh mature leaves, leaf litter fall, and surface soil (0-5 cm) from 0.4 ha, low diversity (oak-hickory-maple), deciduous angiosperm forest are quantified. Owing to degradation and dilution, leaf litter (350 ± 227 μg/g dw) and soil (13 ± 13 μg/g dw) each contain significantly lower concentrations of long-chain n-alkanes than fresh mature leaves (574 ± 291 μg/g dw). The average chain length and odd-even predominance (OEP) of fresh mature leaves increased and decreased, respectively, in leaf litter and soil indicating preferential and progressive degradation of the more abundant C27 and C29 homologues relative to less abundant C31 and C33 homologues. A poor relationship between OEP and a normalised n-alkane ratio(s) demonstrates the large potential effects of inter- and inner-species variability and/or varying effects of degradation on leaf wax n-alkanes, and highlights the potential limitations of the endmember modelling in paleo reconstructions.

MISSOURI; DECIDUOUS forests; FOREST litter; SOILS; WAXES; LITTER (Trash); MAPLE

Chemistry & Ecology, 2020, Vol 36, Issue 9, p810

0275-7540

Academic Journal

10.1080/02757540.2020.1789118