Genetically based trait in a dominant tree affects ecosystem processes

Abstract

Fundamental links between genes and ecosystem processes have remained elusive, although they have the potential to place ecosystem sciences within a genetic and evolutionary framework. Utilizing common gardens with cottonwood trees of known genotype, we found that the concentration of condensed tannins is genetically based and is the best predictor of ecosystem-level processes. Condensed tannin inputs from foliage explained 55-65% of the variation in soil net nitrogen (N) mineralization under both field and laboratory conditions. Alternative associations with litter lignin, soil moisture or soil temperature were relatively poor predictors of litter decomposition and net N mineralization. In contrast to the paradigm that the effects of genes are too diffuse to be important at the ecosystem-level, here we show that plant genes had strong, immediate effects on ecosystem function via a tight coupling of plant polyphenols to rates of nitrogen cycling.

Genotypic variability in Populus tremula L. affects how anthropogenic nitrogen enrichment influences litter decomposition

“…main effects of N, GT, and Tgr). These results suggest that the genetic and environmental factors that influcened litter traits may also have an effect on decomposition, which would agree with the suggestion of Schweitzer et al (2004) that genetically based variation in plant traits may not only be important for a plant population itself, but may result in important extended phenotypes that could alter ecosystem functioning.…”

“…In addition to the differences in leaf traits that occurred in response to N, and among GTs and Tgrs, we also found that leaf and litter values were positively correlated for a number of traits, which agrees with previous studies (King et al 2001;Schweitzer et al 2004). The correlations between leaf and litter values, and the results of the ANOVAs demonstrate that many of the factors that affected some leaf chemistry traits also had significant effects on many of the same litter chemistry traits (i.e.…”

“…The extended phenotype concept (Schweitzer et al 2004) was more explicitly addressed in our second question. We predicted that N addition would increase Gabriel's test that tested the N treatment effect are displayed.…”

“…Donaldson et al 2006;LeRoy et al 2012;Bandau et al 2015). Furthermore, we hypothesized that leaf and litter trait values will be correlated, as has been previously shown (King et al 2001;Schweitzer et al 2004). Secondly, we asked whether GTs and Tgrs interacted with N addition to influence litter decomposition rates.…”

Age-Related Shifts in Leaf Chemistry of Clonal Aspen (Populus tremuloides)

“…For example, variation in tannin concentrations can alter leaf litter quality (Lindroth et al, 2002;Madritch et al, 2006). Concentrations of both nitrogen and phenolics (especially tannins) play important roles in litter decomposition and soil nutrient dynamics in forest soils (Schimel et al, 1996;Northup et al, 1998;Hä ttenschwiler and Vitousek, 2000;Kraus et al, 2003;Schweitzer et al 2004). In fact, an alternative hypothesis to the role of tannins as antiherbivore defenses posits that they may be adaptive in their capacity to regulate proximal nutrient cycling (Northup et al, 1998).…”