Soil macrofauna in SE Mexican pastures and the effect of conversion from native to introduced pastures

摘要: Abstract A large area in the Gulf Coast region of Mexico is pastureland, generally dominated by native grass species, yet little known physical, chemical and biological characteristics limitations soils beneath them. Furthermore, nothing effect converting to introduced grasses on soil ecosystem Mexican pastures. Over last 30 years 60 samples were taken 21 sites throughout SE evaluate macrofauna communities. Of these, 15 at five state Veracruz, Mexico, during dry (April–May) and/or wet (September–October) seasons 1998 1999, specifically compare present These located a N–S transect including three biogeographic regions, separated transverse Neo-volcanic axis. Taking data from all sites, earthworms, ants termites terms density, while earthworms fauna biomass, commonly surpassing weight grazing cattle per hectare. total comparisons populations pastures, important differences communities observed nine occasions, using multivariate analyses. differences, however, depended site sampled, season, sample year, tended be more evident rainy when their maximum numbers. Earthworm different between two pasture types; twice as many species average found (four species) than (two Most only few exotics being found, indicating slow exotic invasion rates or replacement natives exotics. In conclusion, study showed that are pastures that, depending site’s management practices implemented, conversion can significantly alter diversity abundance soil-dwelling macro-invertebrates. However, further studies must undertaken other particularly well-managed with without legume associations, assess whether these results hold true under wider range situations sites.