Management effects on composition and dynamics of cutin and suberin in topsoil under agricultural use

Abstract

Summary We identified and quantified specific biomarkers of shoots and roots (cutin and suberin‐derived compounds, respectively) of three grassland species (Dactylis glomerata L., Festuca arundinacea Schreb. and Lolium perenne L.) in soil under different land use (grass, crop and bare soil) of the SOERE‐ACBB experimental site in Lusignan (France). We also investigated the fate of these markers in soil after conversion from grassland (C3 plants) to Zea mays L. (maize) (C4 plant) with natural 13C isotope abundances. Our results indicated that 9‐hydroxy hexadecanedioic acid and 8(9)(10),16‐dihydroxy hexadecanoic acid may be used as biomarkers for above‐ground biomass, whereas 1,22‐docosandioic acid, 22‐hydroxy docosanoic acid and 24‐hydroxy tetracosanoic acid might be the best below‐ground biomarkers for the plants investigated under the experimental conditions studied. The presence, concentration and shoot–root allocation pattern of these markers were different from those described for other species, which demonstrates the importance of verifying biomarker specificity for each species. Concentrations of cutin and suberin were largest in soil under maize and smallest under bare soil; this corresponded to the biomass added to the two soils. Suberin decreased by 40–64% and cutin by 24–40% during a 6‐year bare fallow, which indicates that root markers were more sensitive than shoot markers to degradation. Changes in 13C isotopic signatures of specific biomarkers after 6 years of maize showed a faster turnover of root than shoot biomarkers, in spite of the much smaller root inputs from maize than from grasses. The sequestration of suberin in soil was more rapid but less durable than that of cutin.

Increasing soil carbon storage: mechanisms, effects of agricultural practices and proxies. A review

“…The C saturation deficit is obtained by subtracting this theoretical C sat value from the actual OM concentration in the fine fraction of the soil. This indicator has recently been used to draw the first map of the potential of organic C storage in the fine fraction in the 0-30 cm horizon of French soils (Angers et al 2011). However, this indicator of the potential gain of soil organic C has so far never been validated and its relevance for predicting C stock patterns consecutive to a change in land use or farming practices remains to be evaluated (O'Rourke et al 2015).…”

Does grassland introduction into cropping cycles affect carbon dynamics through changes of allocation of soil organic matter within aggregate fractions?

“…A deeper follow up of OM accrual after introduction of ley grassland into cropping systems has been carried out using specific plant biomarkers and in situ labelling (Armas-Herrera et al, 2016). Among biomarkers, lignin derived compounds are specifically synthetized by plants and largely stored in soil via selective interactions within some of the compartments of soil matrix (Clemente and Simpson, 2013).…”

Molecular fingerprinting of particulate organic matter as a new tool for its source apportionment: changes along a headwater drainage in coarse, medium and fine particles as a function of rainfalls

“…The main compounds were guaiacyl-like structures (3,4-dimethoxybenzaldehyde, 3,4-dimethoxybenzoic acid methyl ester, erythro and threo-1,2-dimethoxy-4-(1,2,3-trimethoxypropyl)benzene) and syringil-like structures (3,4,5-trimethoxybenzaldehyde and 3,4,5-trimethoxybenzoic acid methyl ester, which is typical of the THM-GC-MS of OM deriving from woody plants; Challinor, 1995). Benzoic acid was not classified in this chemical family since it was negatively (slope of the linear regression model: −0.20; −0.18; −0.17) and poorly correlated (Pearson coefficient, p value: 0.14, 0.002; 0.14, 0.002; 0.21, < 0.001) with 3,4-dimethoxybenzoic acid methyl ester, 3,4,5-trimethoxybenzoic acid methyl ester and 3-(3,4-dimethoxyphenyl)prop-2-enoic acid methyl ester, respectively, that are the main representatives of the three types of lignin units analyzed by THM-GC-MS (Challinor, 1995). As a consequence, calculating the proportion of molecules coming from lignins and tannins was not considered.…”