Exploring potential success factors for soil multifunctionality: effects of agricultural management, soil life and soil carbon

Agricultural soils in intensive farming sustain high crop production yields but endanger other regulating ecosystem services. Strengthening the simultaneous delivery of multiple soil functions is therefore essential to achieve high crop yields while lowering the environmental impact. We investigated how this so-called soil multifunctionality is related to management intensity in conventional and organic arable farming, and to specific practices regarding e.g. crop rotation, fertilization or tillage. We furthermore explored whether soil organic carbon and soil microbiotic parameters could explain relationships between agricultural management and soil functioning.

We collected 57 soil samples in Dutch arable fields and interviewed farmers about their farm management. Soil multifunctionality was measured by aggregating 9 indicators of different functions such as nutrient cycling, soil structure, and disease suppression. We characterized the species composition and abundance of the soil microbial community with 15 parameters, and soil carbon quantity and quality with 16 parameters.

We show that increasing management intensity is associated with declining soil multifunctionality across all fields, whereas multifunctionality was not related with organic vs. conventional farming. Greater soil multifunctionality was also associated with less frequent inversion tillage and higher frequency of grass-legume cover cropping. Bacterial biomass and total soil organic carbon content, respectively, were the strongest biotic and abiotic predictors of soil multifunctionality. No other biotic parameters were related to soil multifunctionality, whereas the majority of soil carbon parameters were significantly related. Our results suggest that reducing management intensity will enhance soil multifunctionality in both conventional and organic farming systems, so that in highly intensive and productive agricultural systems, the paradigm of sustainable intensification should be replaced by “productive de-intensification.”