Etude des successions après abandon des pratiques culturales en Bretagne

Summary Our study is concerning with plant succession in neglected fields and grasslands, using diachronic and synchronic analysis. It is aiming to build dynamic series and to characterize the ecological parameters during these successions. Two spatial scales and two temporal scales is used: on one hand, the bocage landscape scale for long term analysis and on the other hand the parcel scale for short term studies on permanent plots and on permanent lines. Dynamic processes occur very rapidly, using two strategies: by marginal growth from the hedges and by patch growth into the parcel. Various succession scenarios have been observed. They are depending on the parcel history (particularly its original state before abandonment) and also on the biotic environment of the parcel. Most of the plant succession theories can be applied to recolonization of neglected lands.