Cambio en la población de gramíneas en un pastizal abierto bajo sistema de pastoreo continuo en el Norte de México

Human activity modifies habitats, leads to the extinction of species, and causes dispersal of those considered as invaders. The aim of this study was to define the changes in an open grassland subjected to continuous grazing during 30 years. A 2000ha pasture was considered, where frequency, density, dominance, and productivity of the species present were established in 1979, 1999 and 2008. An increase of 16 species in 2008 compared to 1979 was found, the loss of seven species during the study period was recorded, as well as a biomass increase of 360%, which allowed to estimate a change in stocking rate from 7.6 to 2.11ha per animal unit. The pressure of continuous grazing for 30 years within the mid-size open grassland induced changes in the composition, number of species, and forage production.