Land use change effects on catchment streamflow response in a humid tropical montane cloud forest region, central Veracruz, Mexico
Sergio López-Ramírez, Leonardo Sáenz, Alex Mayer, Lyssette E. Muñoz‐Villers, Heidi Asbjornsen, Z. Carter Berry, Nathaniel Looker, Robert H. Manson, León Rodrigo Gómez‐Aguilar
Abstract
Abstract Tropical montane cloud forests (TMCF) are recognized for their capacity to maintain high dry‐season baseflow and a host of other ecosystem services. Substantial areas of TMCF have been converted to pasture and crops such as coffee, while in other areas TCMF are recovering. However, little is known about the effects of this complex dynamic on catchment hydrology. We investigated the effect of land use on rainfall‐runoff response in five neighbouring headwater micro‐catchments in central Veracruz, Mexico, dominated by either mature TMCF (MF), young (20 year‐old) and intermediate (40 year‐old) naturally regenerating TMCF (YF and IF, respectively), shaded coffee (SC), and an intensively grazed pasture (IP). We used a 4‐year record of high‐resolution rainfall and streamflow (10 min) data collected from 2015 to 2019. These data were analysed via comparison of hydrologic metrics that summarize streamflow responses at various time scales and magnitudes. Results showed no statistical difference in the regulation capacity of high flows in the micro‐catchment with 20 years of natural regeneration, compared to the MF. In terms of baseflow sustenance, our results support the hypothesis that MF and IF better promote this hydrologic service than the other land uses. SC exhibited a high capacity to modulate peak flows comparable to that of MF, and an intermediate capacity to sustain baseflow, suggesting that the integrated functioning of this micro‐catchment was largely preserved. Finally, 40 years of intense pasture management was found to have degraded the soil hydraulic properties of IP; mainly, reducing its infiltration capacity, causing a fivefold greater peak flow response and a lower baseflow compared to MF.