An overview of the applicability of functional diversity in Biological Conservation.

Functional diversity is increasingly pointed as a useful approach to reach Biological Conservation goals. Here, we provide an overview of the functional diversity approach status in the Biological Conservation field. We sought for peer-reviewed papers published over a period of twenty years (from 1994 to 2014). First we used the general topic "functional diversity" and then refined our search using the key-word "conservation". We have identified the conservation strategies addressed, the organism studied, and the continent of study site in each paper. Thirteen classes of conservation strategies were identified. Plants were the most commonly studied organism group and most study-sites were located in Europe. The functional diversity approach was introduced in the Biological Conservation field in the early 2000's and its inclusion in conservation strategies is broadly advised. However, the number of papers that operationalise such inclusion by developing models and systems is still low. Functional diversity responds differently and eventually better than other measures to changes in land use and management, which suggests that this approach can potentially better predict the impacts. More studies are needed to corroborate this hypothesis. We pointed out knowledge gaps regarding identification of the responses for functional diversity about urban impacts and in research on the level of management intensity of land needed to maintain functional diversity. We recommend the use of functional diversity measures to find ecological indicators. Future studies should focus on the development of functional diversity measures of other taxa beyond plants as well as test hypothesis in tropical ecosystems.