Reference : An indicator for organic matter dynamics in temperate agricultural soils
Scientific journals : Article
Life sciences : Agriculture & agronomy
Life sciences : Phytobiology (plant sciences, forestry, mycology...)
Life sciences : Environmental sciences & ecology
An indicator for organic matter dynamics in temperate agricultural soils
Wesemael, Bas Van [> >]
Chartin, Caroline [> >]
Wiesmeier, Martin [> >]
Lützow, Margit Von [> >]
Hobley, Eleanor [> >]
Carnol, Monique mailto [Université de Liège - ULiège > Département de Biologie, Ecologie et Evolution > Ecologie végétale et microbienne >]
Krüger, Inken [> >]
Campion, Morgane [> >]
Roisin, Christian [> >]
Hennart, Sylvain [> >]
Kögel-Knabner, Ingrid [> >]
Agriculture, Ecosystems and Environment
62 - 75
Yes (verified by ORBi)
[en] Soil organic matter fractionation ; Indicator ; Soil organic carbon dynamics ; Long-term trials ; Organic matter management
[en] The heterogeneity of soil organic matter (SOM) and the small changes in soil organic carbon (SOC) compared to large total SOC stocks hinder a robust estimation of SOC turnover, in particular for more stable SOC. We developed a simple fractionation protocol for agricultural topsoils and tested it extensively on a range of soils in southern Belgium, including farmed soils, soils from long-term field trials, and paired sites after recent conversion to conservation farming. Our simple fractionation involves shaking the soil, wet sieving over 20 μm and analysing the SOC concentration in the soil as well as in the fine fraction (<20 μm). Eight biological indicators measured in an earlier study across the same monitoring network for the 0–10 cm topsoil were analysed in a conditional inference forest model in order to investigate the factors influencing the SOC fractions. Soil microbial biomass N explained the largest proportion of variation in both fractions. The fine fraction was also associated with factors explaining the regional trend in SOC distribution such as farmyard manure input, precipitation, land use and flow length. The variation in SOC content between treatments both in long-term trials and in farmers’ fields converted to conservation management was mainly attributed to changes within the coarse fraction. Thus, this fraction proves to be sensitive to management changes, although care should be taken to sample deep enough to represent the former plough layer inherited from the conventional tillage practice. Furthermore, the ratio between the coarse and the fine fraction showed a linear relationship (r² = 0.66) with the relative changes in SOC concentration over the last ten years. These fractions derived from a simple analytical approach are thus useful as an indicator for changes in SOC concentration. In analogy to biological indicators such as the soil microbial biomass C, the relationship between the fractions and relative changes in SOC concentration are likely to depend on climate conditions. Our methodology provides an indicator for use in routine analysis of agricultural topsoils, which is capable of predicting the effects of management practices on SOC concentrations in the short to mid-term (5–10 years).

File(s) associated to this reference

Fulltext file(s):

Restricted access
Wesemael et al. - 2019 - Agriculture , Ecosystems and Environment An indicator for organic matter dynamics in temperate agricultural soi.pdfPublisher postprint4.73 MBRequest copy

Bookmark and Share SFX Query

All documents in ORBi are protected by a user license.