Conclusions
demonstrate the important hydrologic impacts of the conversion and
preservation of TCMF. The pasture-dominated catchment showed a lower
baseflow compared to the primary forest, regardless of its similar
rainfall, and it also presented a fivefold increase in peak discharge
response. These results suggest that 40 years of high intensity pasture
management can deteriorate the hydraulic properties of volcanic soils,
mainly in terms of infiltration capacity reduction.
This work indicates that despite the potential changes in the water and
energy balance due to forest conversion to shade coffee alternatives,
the capacity to sustain baseflow in shaded coffee dominated
micro-catchments is largely preserved through the end of the dry season.
It was also found that shade coffee systems can preserve the soil
capacity to modulate peak flows during storms. We found that daily
streamflow regimes of an intermediate age forest more closely resembled
a primary forest. However, storm runoff event responses across all the
forested catchments were not statistically different. Older forests were
associated with better soil conditions, particularly higher soil
infiltration capacity and thus greater recharge of subsurface water
storages. In conclusion, our results showed the importance of protecting
naturally regenerating forest to promote hydrologic services.
The major implications of our findings for managers of payments for
watershed services and other programs promoting conservation of
hydrologic services are: 1) shade coffee may provide similar hydrologic
services to forests in these types of programs, but more work on coffee
farms with different management is needed to support this hypothesis; 2)
higher conservation priority should be given to mature and older
regenerating TMCF, particularly those located at higher elevations; and
3) conversion to pasture should be avoided. However, more research is
needed to better understand the energy and mass dynamics on regenerating
TMCF across a wider range of elevations and forest ages.