Diagnosis and determinants of grassland sustainability. Soil and the sustainability of grasslands: a virtuous circle

The physical, chemical and biological properties of the soil will affect plant growth and condition the sustainability of the grasslands. Thus, soil compaction due to grazing or machine traffic will result in a loss of yield, the effects being variable according to texture (more pronounced on more clayey soils) and season. On the other hand, the preservation of soil organisms and associated functions will contribute to increasing yields. On the other hand, grassland management will also impact soil properties. Thus, the introduction of grassland in the crop rotation will quickly allow, from the second year, to favor soil biodiversity (fauna, microorganisms) and their activities. More broadly, the introduction of grassland into an annual crop rotation positively influences the maintenance of soil structure and the conservation of biodiversity, without modifying water regulation. The positive effect inherited from grasslands in the rotation can be observed even three years after recultivation. The sustainability of the grasslands will be conditioned by several factors: the duration of the grassland in the rotation, grazing management (load, period), fertilization and plant diversity. Levers exist to ensure the sustainability of these temporary or permanent grassland systems.