A guide to assess the biological fertility of soils
A guide to assess the biological fertility of soils
How can practices be optimized to both store sufficient carbon in soils in a sustainable manner and increase the organic matter degradation activity that leads to the supply of nitrogen for plants? The Microbioterre project, which ended in 2021, has just released an interpretation guide for 12 relevant microbiological indicators.
Carbon storage in soils, mineralization and the availability of mineral elements for crops depend on soil microorganisms, which can thus enhance crop performance and move towards more sustainable cropping systems.
Referencing biological indicators present in the soil
Funded by the Casdar and led by Arvalis-Institut du végétal, this project, in which Terres Inovia was an active partner, delivered its results in 2022 after four years of work. "This project sought to evaluate and reference soil microbiology indicators, to be integrated into routine soil analyses carried out by laboratories, in order to improve the management of organic restitutions in field crop and mixed crop-livestock systems," explains Anne-Sophie Perrin, soil and environment researcher for Terres Inovia.
Measurements on 18 experimental sites and a synthesis of scientific results
Experimental systems were studied and field observations were made, with sampling and analyses on 18 medium- and long-term experimental sites (ranging from 6 to 48 years), including cropping systems with different organic restitution practices (waste products, crop residues, plant cover of various types).
Twenty-five different analyses were evaluated and some were discarded because they were redundant or provided little information in field crops or mixed cropping. The criteria for selecting indicators also included the cost and ease of use of routine methods.
A reference system was thus created from 183 field crop plots without grassland. Supplemented by an analysis of the results of previous projects and scientific publications, this work also made it possible to identify agronomic levers to be implemented to improve soil functions according to farmers' specific objectives.
An interpretation guide for the analysis of microbiological indicators
This work has led to the development of a comprehensive guide on how to carry out this diagnosis and interpret the results of the analyses. Intended for farmers and technicians, this very practical guide first presents the diagnostic approach, details, by sheet, and then explains the procedure for taking, packaging and sending samples to perform a soil analysis.
Find the complete guide for the interpretation of the bioindicators analysis and the presentation of the Microbioterres project restitution seminar in attachments