The Regulation by Phenolic Compounds of Soil Organic Matter Dynamics under a Changing Environment

Abstract

Phenolics are the most abundant plant metabolites and are believed to decompose slowly in soils compared to other soil organic matter (SOM). Thus, they have often been considered as a slow carbon (C) pool in soil dynamics models. Here, however, we review changes in our concept about the turnover rate of phenolics and quantification of different types of phenolics in soils. Also, we synthesize current research on the degradation of phenolics and their regulatory effects on decomposition. Environmental changes, such as elevated CO2, warming, nitrogen (N) deposition, and drought, could influence the production and form of phenolics, leading to a change in SOM dynamics, and thus we also review the fate of phenolics under environmental disturbances. Finally, we propose the use of phenolics as a tool to control rates of SOM decomposition to stabilize organic carbon in ecosystems. Further studies to clarify the role of phenolics in SOM dynamics should include improving quantification methods, elucidating the relationship between phenolics and soil microorganisms, and determining the interactive effects of combinations of environmental changes on the phenolics production and degradation and subsequent impact on SOM processing.

The effect of roots and easily available carbon on the decomposition of soil organic matter fractions in boreal forest soil

“…The signal for phenols suggests the presence of root exudates because phenols are important compounds in the exudate matrix (Qiao et al, 2014). In general, a stronger phenolic signal occurred in the 1293-1265 cm −1 region (Tatzber et al, 2011) of the residual fraction in treatments with seedlings, where they represent a relatively stable C pool (Min et al, 2015).…”

Inferring Methane Production by Decomposing Tree, Shrub, and Grass Leaf Litter in Bog and Rich Fen Peatlands

“…However, leaves from shrubs and needleleaf trees are notoriously full of phenolics (Dorrepaal et al, 2005), yet decaying leaf litter from shrubs, and from needle-leaf trees here and in other studies (Yavitt and Williams, 2015;Corteselli et al, 2017) supported methanogenesis, which runs counter to the toxicity argument. Moreover, because most phenolics are water soluble (Min et al, 2015), they are likely leached away making the residue a less toxic habitat than expected from initial litter chemistry. Thus, the overwhelming prevalence of methanogenesis associated with litter decay in the rich fens challenges a single explanation.…”

Fate and Toxicity of Chlorinated Phenols of Environmental Implications: A Review

“…Phenolics are the most abundant plant metabolites and are believed to decompose slowly in soils compared to other soil organic matter (SOM). Thus, they have often been considered as a slow carbon pool in soil dynamics models [5]. The release of phenolic compounds to the soil can be by leaching from treated wood products, atmospheric deposition in precipitation (such as rain and snow), herbicidal application, and spills at industrial facilities and at hazardous waste sites.…”