Significance: People are fascinated by the amazing diversity of tropical forests and will be surprised to learn that robust estimates of the number of tropical tree species are lacking. We show that there are at least 40,000, but possibly more than 53,000, tree species in the tropics, in contrast to only 124 across temperate Europe. Almost all tropical tree species are restricted to their respective continents, and the Indo-Pacific region appears to be as species-rich as tropical America, with each of these two regions being almost five times as rich in tree species as African tropical forests. Our study shows that most tree species are extremely rare, meaning that they may be under serious risk of extinction at current deforestation rates.

Significance: Identifying and explaining regional differences in tropical forest dynamics, structure, diversity, and composition are critical for anticipating region-specific responses to global environmental change. Floristic classifications are of fundamental importance for these efforts. Here we provide a global tropical forest classification that is explicitly based on community evolutionary similarity, resulting in identification of five major tropical forest regions and their relationships: ( i ) Indo-Pacific, ( ii ) Subtropical, ( iii ) African, ( iv ) American, and ( v ) Dry forests. African and American forests are grouped, reflecting their former western Gondwanan connection, while Indo-Pacific forests range from eastern Africa and Madagascar to Australia and the Pacific. The connection between northern-hemisphere Asian and American forests is confirmed, while Dry forests are identified as a single tropical biome.

Danielsen, F., T. Adrian, S. Brofeldt, M. van Noordwijk, M. K. Poulsen, S. Rahayu, E. Rutishauser, I. Theilade, A. Widayati, N. The An, T. Nguyen Bang, A. Budiman, M. Enghoff, A. E. Jensen, Y. Kurniawan, Q. Li, Z. Mingxu, D. Schmidt-Vogt, S. Prixa, V. Thoumtone, Z. Warta, and N. Burgess. 2013. Community monitoring for REDD+: international promises and field realities. Ecology and Society 18(3): 41.http://dx.doi.org/10.5751/ES-05464-180341

The UNFCCC mechanism for Reducing Emissions from Deforestation and Degradation in developing countries (REDD+) represents an unprecedented opportunity for the conservation of forest biodiversity. Nevertheless, there are widespread concerns surrounding the possibility of negative environmental outcomes if biodiversity is not given adequate consideration throughout the REDD+ process. We propose a general framework for incorporating biodiversity concerns into national REDD+ programmes based on well-established ecological principles and experiences. First, we identify how biodiversity distribution and threat data, together with data on biodiversity responses to forest change and management, can be readily incorporated into the strategic planning process for REDD+ in order to identify priority areas and activities for investment that will deliver returns for both carbon and biodiversity. Second, we propose that assessments of changes in biodiversity following REDD+ implementation could be greatly facilitated by paralleling, where possible, the existing IPCC architecture for assessing carbon emissions. A three-tiered approach is proposed for biodiversity assessment, where lower tiers can provide a realistic starting point for countries with fewer data and lower technical capacities. Planning and assessment of biodiversity safeguards for REDD+ need not overburden an already encumbered UNFCCC process. Immediate progress is already possible for a large number of developing countries, and a gradual, phased approach to implementation would minimise risks and facilitate the protection of additional biodiversity benefits from REDD+ activities. Greater levels of coordination between the UNFCCC and CBD, as well as other agencies and stakeholder groups interested in forest conservation are needed if biodiversity safeguards are to be fully adopted and implemented

The genus Dalbergia contains many valuable timber species threatened by illegal logging and deforestation, but knowledge on distributions and threats is often limited and accurate species identification difficult. The aim of this study was to apply DNA barcoding methods to support conservation efforts of Dalbergia species in Indochina. We used the recommended rbcL, matK and ITS barcoding markers on 95 samples covering 31 species of Dalbergia, and tested their discrimination ability with both traditional distance-based as well as different model-based machine learning methods. We specifically tested whether the markers could be used to solve taxonomic confusion concerning the timber species Dalbergia oliveri, and to identify the CITES-listed Dalbergia cochinchinensis. We also applied the barcoding markers to 14 samples of unknown identity. In general, we found that the barcoding markers discriminated among Dalbergia species with high accuracy. We found that ITS yielded the single highest discrimination rate (100%), but due to difficulties in obtaining high-quality sequences from degraded material, the better overall choice for Dalbergia seems to be the standard rbcL+matK barcode, as this yielded discrimination rates close to 90% and amplified well. The distance-based method TaxonDNA showed the highest identification rates overall, although a more complete specimen sampling is needed to conclude on the best analytic method. We found strong support for a monophyletic Dalbergia oliveri and encourage that this name is used consistently in Indochina. The CITES-listed Dalbergia cochinchinensis was successfully identified, and a species-specific assay can be developed from the data generated in this study for the identification of illegally traded timber. We suggest that the use of DNA barcoding is integrated into the work flow during floristic studies and at national herbaria in the region, as this could significantly increase the number of identified specimens and improve knowledge about species distributions.