Forest certification as a policy option in conserving biodiversity: An empirical study of forest management in Tanzania

Abstract Forest certification management standards aim at maintaining forest ecosystem integrity, including forest biodiversity conservation. However, studies from the Amazon and Congo basin find that forest certification may not protect forest biodiversity and ecosystems, and may therefore be unsustainable. This study evaluates the influence of forest certification on conserving biodiversity. Specifically, we (a) estimate tree (adult and seedling) species richness, diversity and density among different forest management regimes; (b) assess the relationship between environmental and human forest use variables, and species richness, diversity and density among the forest management regimes; and (c) assess the influence of forest governance of villages adjacent to the forests on tree (adult and seedling) species richness, diversity and density among the forest management regimes. This is achieved in a comparative study of Forest Stewardship Council certified community forests, non-certified open access forests, and non-certified state forest reserves in the Kilwa District in Tanzania. Our results show that forest certification standards and implementation processes are positively related to biodiversity conservation. There are significantly higher tree (adults) species richness, diversity, and density in certified community forests than in open access forests and state forest reserves. These findings suggest that forest certification may be a good policy option to conserve biodiversity. The present study is one of the first studies in tropical Africa, which contributes to the limited data on the influence of forest certification on conserving biodiversity. Our results may also serve as baseline for further research on the contribution of certified forests in conserving biodiversity at both temporal and spatial scales.