Impacts of national-scale land use zoning policies on forest cover changes in Cameroon and Bhutan

Particularly threatened and sheltering the most species-rich habitats worldwide, tropical forests are increasingly monitored and targeted by conservation strategies. One of these strategies, land use zoning, consists of segmenting the landscape into units where human access and uses are restricted to specific activities or agents, such as protection or production activities or community management. Via two case studies, Cameroon and Bhutan, we assessed the effectiveness of national-scale land use zoning in contributing to forest conservation. Firstly, we assessed forest cover changes using remote sensing imagery and a change detection combining classifications with image differencing on spectral indices. We observed limited forest cover changes in our Cameroon study site, with a net forest gain during the 2000s. For Bhutan, we showed that, nation-wide, forests experienced only limited land cover changes between 1990 and 2011. A small net decrease during the 1990s was followed by a comparable net increase during the 2000s. Secondly, effectiveness assessments were performed using statistical matching, which consisted of pairing areas under specific zoning with similar areas outside zoning. In Cameroon, units included in the permanent forest estate succeeded at deterring forest loss, with logging concessions even curtailing forest degradation. In Bhutan, both protected areas and forest production units contributed to forest conservation. This thesis gave clear evidence that restricting land uses in forestlands dedicated to timber extraction can also participate in forest protection if proper management is enforced. This advocated for a less uniform vision of tropical forest conservation, still largely dominated by protected areas.