Overall, FSC and PEFC certifications produce positive environmental impacts, compared to non-certified, conventionally logged forests. Strong positive impacts are in particular reported for fauna, where all studies included demonstrate that both FSC and PEFC succeed in preserving animal species, including ones listed as endangered and vulnerable by IUCN. However, these positive outcomes are only achieved if logging intensity is low, if certified forests are surrounded by a relatively unfragmented landscape, and if hunting is strictly controlled. Such highlights the crucial importance of contextual, enabling conditions for certification systems to produce positive results. Generally, impacts on flora and ecosystem services are also positive, but moderately so.
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