Report on candidate models and adaptations: Deliverable 6.2 Towards climate-smart sustainable management of agricultural soils

Crop diversification is a potentially attractive agricultural practice for enhancing organic carbon (C) storage in soils. The aim of EnergyLink is to better understand the link between crop diversity and carbon sequestration by the soil microbiome across a pan-European pedo-climatic gradient. The central hypothesis is that greater crop diversity results in more efficient microbial use of C, thus enhancing the potential of soils to store C. The underlying mechanisms will be elucidated by combining classical and molecular level methods in a bioenergetics framework.
Work package 6 on “Soil Organic Matter Modelling” aims to assess the relative impact of including the soil microbiome in models for soil organic C (SOC) sequestration on the assessment of C sequestration. More specifically, task 6.2 aims to screen current and next generation SOM models for their suitability and adaptability to include the soil biome, by improvements based on, or full integration of, the Energy-Model. All the approaches have been considered, included statistical methods available for indicator development based on bacterial community data. Investigating if soil biota respond in a predictable manner to human land use and soil physico-chemical changes across a wide variety of different soils, spatial gradients and climatic conditions will reveal their potential to serve widely also as indicators of soil quality. It will create predictive models through identifying discriminating independent variables and it could be used to classify new samples from an assessment of the biological data. For the adaptability and the suitableness, Millennial and ROTHC models have been chosen because the first one defines pools as measurable entities while the second one is a model for the turnover of C in non-waterlogged topsoils. For these reasons, they could be adapted for the EnergyLink purposes, i.e. the study of the relative impact of the soil
microbiome on the formation and persistence of SOC under different pedo-climatic conditions.