Conversion of thornscrub to buffelgrass pasture in northwestern Mexico: Microclimatic consequences

• We evaluated soil temperature and moisture to document changes in microclimate as a consequence of buffelgrass conversion.
• We found greater soil temperatures in the pasture after the wet season with values that reached 6 °C above the thornscrub.
• Soil moisture content showed significant greater values in the thornscrub than in the pasture.
• Our data suggest that buffelgrass conversion modify the local microclimate and probably the natural regeneration in pastures.

Buffelgrass (Pennisetum ciliare) have been planted in large areas of northwestern Mexico for cattle grazing. Previous studies have documented how buffelgrass conversion affects several ecological processes; however, very few studies have documented how conversion affects local microclimate. We used data on soil temperature and moisture to document seasonal changes in microclimate as a consequence of land conversion. We describe soil and air temperature and soil moisture content in a thornscrub and an adjacent buffelgrass pasture, in open spaces and under trees, during one year. Air temperature in the pasture exceeded ∼1 °C the value in the thornscrub during the colder months. Mean soil temperatures were slightly greater in the thornscrub during the dry season but during the wet season, mean temperatures were greater in the pasture reaching differences of ∼2 °C. Maximum monthly soil temperatures were greater in the pasture after the wet season with values that reached 6 °C above the thornscrub. Soil moisture showed significant greater values in the thornscrub than in the pasture. Our data suggest that conversion of thornscrub to buffelgrass pasture modify the local microclimate, which in turn could influence the process of regeneration of native species persisting in pastures.