Participatory management of biotic forest disturbances in community forests of Oaxaca, Mexico
Biotic forest disturbances can alter forest structure and function and provision of environmental services, affecting the people who depend on forest ecosystems. In Oaxaca State, southern Mexico, over 80% of forest lands are under a common property regime and local communities are responsible for management and protection of their community forests. Biotic forest disturbances are impacting many of Oaxaca´s community forests, notably bark beetles (Dendroctonus sp.) in temperate pine forests and invasive bracken fern (Pteridium aquilinum) in tropical forests. The objectives of this study were to investigate how community forests manage the challenges and mitigate the negative impacts of bark beetle outbreaks and bracken fern invasion. How do they restore the ecosystems they depend on? We analyzed a set of community forests in pine forest ecosystems and a pair of forest communities located in a small tropical forest watershed. We reviewed scientific literature, carried out field visits in affected communities, conducted semi-structured interviews, and met with federal and state government forestry agencies. Cartographic analysis was conducted for the bracken fern case.
State and federal forestry agencies conduct annual diagnoses of bark beetle outbreaks and, based on these, promote sanitation treatments in affected community forests. Forest communities are legally mandated to manage bark beetle outbreaks. However, the type of intervention depends on local governance and organizational capacity. We suggest two models that illustrate those conditions and level of involvement for forest sanitation: 1) independent communities where local organizations assume management responsibility and 2) dependent communities where agencies provide technical and financial support and supervise the forest management. In contrast with bark beetle outbreaks, government agencies have not addressed the bracken fern invasion as a biotic forest disturbance of concern. Our cartographic analysis found that 14% (465 ha) of the studied small-watershed is invaded by bracken fern. Because bracken invasion affects mainly agricultural areas, farmers abandon them and expand the agricultural frontier to secondary or mature forests. After dissemination of information on ecological degradation caused by bracken, communities started to work on a participatory restoration strategy that could improve farmers’ livelihoods, while reducing future pressures on forests. Because the role that community forests play in maintaining forest health and restoring areas affected by insect outbreaks and invasive plant species, we suggest that that government programs, development projects, and economic incentives can be fundamental to promote community participation to maintain forest health and improve social-ecological resilience in forestry landscapes.