Soil networks become more connected and take up more carbon as nature restoration progresses

Abstract

Soil organisms have an important role in aboveground community dynamics and ecosystem functioning in terrestrial ecosystems. However, most studies have considered soil biota as a black box or focussed on specific groups, whereas little is known about entire soil networks. Here we show that during the course of nature restoration on abandoned arable land a compositional shift in soil biota, preceded by tightening of the belowground networks, corresponds with enhanced efficiency of carbon uptake. In mid- and long-term abandoned field soil, carbon uptake by fungi increases without an increase in fungal biomass or shift in bacterial-to-fungal ratio. The implication of our findings is that during nature restoration the efficiency of nutrient cycling and carbon uptake can increase by a shift in fungal composition and/or fungal activity. Therefore, we propose that relationships between soil food web structure and carbon cycling in soils need to be reconsidered.

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

“…The contribution of belowground input to C storage occurs through the persistence of plant residues or via the stimulation of soil microbial activity and the increase of the contribution of microbial necromass to the slow cycling soil OM pools DuPont et al 2014;Lange et al 2015;Morriën et al 2017).…”

Biotic interactions and trait-based ecosystem functioning in soil

“…Also in this case, the use of isotopic ratios may disclose differences in the trophic response of the soil community to environmental conditions, overcoming the problem of differences in taxonomic resolution (Morriën et al 2017).…”

“…Therefore, a priori functional traits may turn out to be unsuitable to detect changes in trophic relations. In this context, molecular techniques and stable isotope analysis are promising techniques to elucidate food preference in soil animals (Chapter 2) and can provide insight into trophic connections and interaction strength (Morriën et al 2017).…”

“…The current classification in functional groups implies that only variations in abundances can be detected; due to the high number of species belonging to the same functional group, changes in species assemblage will rarely result in a complete disappearance of a specific functional group from the soil community. In this case, the isotopic signature would enable the identification of trophic positions and carbon sources used within the soil food web , Morriën et al 2017). …”

Range-expanding plant species and their belowground neighbours : digging into novel interactions

“…More concise experiments, possibly with single nematode-antagonists, are needed to examine how differences in plant chemistry could affect such belowground multi-trophic interactions (Rasmann et al 2005;Schulz-Bohm et al 2017). Alternatively, studies using labelled CO 2 could target the question whether soil food webs show divergent functioning under range-expanding plant species that possess novel chemistry (Morriën et al 2017). …”