Contributors: Institut d'écologie et des sciences de l'environnement de Paris (iEES Paris); Institut de Recherche pour le Développement (IRD)-Sorbonne Université (SU)-Université Paris-Est Créteil Val-de-Marne - Paris 12 (UPEC UP12)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE); Instrumentation, Moyens analytiques, Observatoires en Géophysique et Océanographie (IMAGO); Environnement Méditerranéen et Modélisation des Agro-Hydrosystèmes (EMMAH); Avignon Université (AU)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE); Centre d’Etudes et de Recherche de Djibouti (CERD); Laboratoire d'étude des Interactions Sol - Agrosystème - Hydrosystème (UMR LISAH); Institut de Recherche pour le Développement (IRD)-AgroParisTech-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)-Institut Agro Montpellier; Institut national d'enseignement supérieur pour l'agriculture, l'alimentation et l'environnement (Institut Agro)-Institut national d'enseignement supérieur pour l'agriculture, l'alimentation et l'environnement (Institut Agro); Soils and Fertilizers Research Institute (SFRI); Vietnam Academy of Agricultural Sciences (VAAS); Cités, Territoires, Environnement et Sociétés (CITERES); Université de Tours (UT)-Centre National de la Recherche Scientifique (CNRS); School of Chemical Sciences, Mahatma Gandhi University, Kottayam; Mahatma Gandhi University Kerala; Botanique et Modélisation de l'Architecture des Plantes et des Végétations (UMR AMAP); Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD Occitanie )-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)-Université de Montpellier (UM); Land Development Department (LDD); Department of Agricultural Land Management Vientiane (DALaM); Ministry of Agriculture and Forestry of Laos; This work was carried out with the financial support of the "Le reseau des bassins versants (SOERE RBV) ". S. Grellier thanks the Domaine National of Chambord for using the forest as an experimental research site. She thanks the University of Tours and the COSTAUD project for financial support and for offering other facilities during the experiment. We are grateful to Myriam Eddine, Loic Salauen and Denis Frizat for their student master work on this experiment. We thank all the hospitals and hospital staff who participated in the study by lending their X-ray computed tomography equipment.
نبذة مختصرة : International audience ; It is well known that biopores are crucial for soil functioning. However, their dynamics is rarely studied and their origin with regards to the soil organisms involved is still hard to determine. In this study we investigated the diversity of biopores and their regeneration rates in situ in various pedoclimatic conditions. Our approach involved field incubation of repacked soil cores with lateral openings across nine study sites in five countries (France, Vietnam, India, Laos and Thailand). After 12 months, biopores were characterized by X-ray computed tomography and grouped according to their diameter, length and sphericity index using principal component analysis followed by K-means clustering. The regeneration dynamics of biopores was assessed by comparing those created after one year of incubation to the biopores determined in soil cores taken from the surrounding soils (assuming the latter are in a steady-state). Additionally, we examined the relationships between newly formed biopores and soil macrofauna taxa. Our results evidenced significant variability in biopore diameter (0.90 to 15.84 mm), length (1 to 1600 mm) and sphericity index (0.03 to 0.93). We propose 10 biopore groups allowing to distinguish most of the study sites. Complete regeneration of biopores after 12 months was achieved in seven out of nine sites. Three groups of biopores showed a positive relation with earthworm abundance (r values ranged from 0.69 to 0.90), whereas the other groups of biopores showed no association with any macrofauna taxa. We conclude that biopore formation can be assessed under field conditions with repacked soil cores, regardless the pedoclimatic conditions. However, the involvement of macrofauna other than earthworms in biopore formation still remains to be unraveled. To capture their contribution to biopore formation, improvements of the repacked soil core approach and complementary laboratory experiments were suggested.
Processing Request
No Comments.