Impact of climate change on grasses cultivation potential of three altitudinal strata-agricultural lands of Mexico

This study estimated the impact of climate change in the period 2040-2069 on six grasses potential areas in three altitudinal zones of Mexico: 0 to1200 m (lowlands), 1200 to 2200 m (midlands) and >2200 m (highlands). Topography, soil and climate variables were used to depict potential areas. Climate data for  1961-1990 (reference climatology) and 2040-2069 were obtained from the WorldClim Earth System Grid Portal and were worked in 2.5 arc minutes raster images in the Idrisi Selva System. For the 2040-2069 climatology, three GCMs were considered: MPIM-ECHAM5, MIROC3.2 (medres) and UKMO_HADCM3, under A2 emissions scenario. The results showed that most of the potential areas with optimal conditions for grasses will remain in lowlands, however the surface with these conditions will tend to decrease for Cenchrus ciliaris, Andropogon gayanus and Brachiaria mutica at a rate of 35-49%, 2-63% and 15-30%, respectively, which will affect mostly to C. ciliaris, since it will tend to migrate to midlands. Optimal conditions surface for C. gayana and C. dactylon will not change in lowlands, but will increase in midlands 63-103% and 74-90%, respectively. For H. rufa, the optimum conditions surface will rise 5-17% in lowlands and 391-449% in midlands. In highlands, potential areas for grasses were estimated majorly as suboptimal, however with climate change C. ciliaris, C. gayana and C. dactylon will increase their optimal conditions surface in highlands. For A. gayanus, B. mutica and H. rufa no optimal conditions surface was determined in highlands neither in the reference climatology nor in the future climatologies.   Key words: Climate change and forage grasses; Climate change and altitudinal zones; Tropical and subtropical grasses.