University of Wisconsin–Madison
Spatial Analysis For Conservation and Sustainability

Payments for ecosystem services in Mexico reduce forest fragmentation

Download Ramirez-Reyes_et_al-2018-Ecological_Applications

Forest fragmentation can lead to habitat reduction, edge increase, and exposure to disturbances.
A key emerging policy to protect forests is payments for ecosystem services (PES), which
offers compensation to landowners for environmental stewardship. Mexico was one of the first countries
to implement a broad-scale PES program, enrolling over 2.3 Mha by 2010. However, Mexico’s
PES did not completely eliminate deforestation in enrolled parcels and could have increased incentives
to hide deforestation in ways that increased fragmentation. We studied whether Mexican forests
enrolled in the PES program had less forest fragmentation than those not enrolled, and whether the
PES effects varied among forest types, among socioeconomic zones, or compared to the protected
areas system. We analyzed forest cover maps from 2000 to 2012 to calculate forest fragmentation. We
summarized fragmentation for different forest types and in four socioeconomic zones. We then used
matching analysis to investigate the possible causal impacts of the PES on forests across Mexico and
compared the effects of the PES program with that of protected areas. We found that the area covered
by forest in Mexico decreased by 3.4% from 2000 to 2012, but there was 9.3% less forest core area.
Change in forest cover was highest in the southern part of Mexico, and high-stature evergreen tropical
forest lost the most core areas (17%), while oak forest lost the least (2%). Our matching analysis
found that the PES program reduced both forest cover loss and forest fragmentation. Low-PES areas
increased twice as much of the number of forest patches, forest edge, forest islets, and largest area of
forest lost compared to high-PES areas. Compared to the protected areas system in Mexico, high-PES
areas performed similarly in preventing fragmentation, but not as well as biosphere reserve core zones.
We conclude that the PES was successful in slowing forest fragmentation at the regional and country
level. However, the program could be improved by targeting areas where forest changes are more frequent,
especially in southern Mexico. Fragmentation analyses should be implemented in other areas
to monitor the outcomes of protection programs such as REDD+ and PES.