The Brazilian freshwater wetscape: Changes in tree community diversity and composition on climatic and geographic gradients.

Wetlands harbor an important compliment of regional plant diversity, but in many regions data on wetland diversity and composition is still lacking, thus hindering our understanding of the processes that control it. While patterns of broad-scale terrestrial diversity and composition typically correlate with contemporary climate it is not clear to what extent patterns in wetlands are complimentary, or conflicting. To elucidate this, we consolidate data from wetland forest inventories in Brazil and examine patterns of diversity and composition along temperature and rainfall gradients spanning five biomes. We collated 196 floristic inventories covering an area >220 ha and including >260,000 woody individuals. We detected a total of 2,453 tree species, with the Amazon alone accounting for nearly half. Compositional patterns indicated differences in freshwater wetland floras among Brazilian biomes, although biomes with drier, more seasonal climates tended to have a larger proportion of more widely distributed species. Maximal alpha diversity increased with annual temperature, rainfall, and decreasing seasonality, patterns broadly consistent with upland vegetation communities. However, alpha diversity-climate relationships were only revealed at higher diversity values associated with the uppermost quantiles, and in most sites diversity varied irrespective of climate. Likewise, mean biome-level differences in alpha-diversity were unexpectedly modest, even in comparisons of savanna-area wetlands to those of nearby forested regions. We describe attenuated wetland climate-diversity relationships as a shifting balance of local and regional effects on species recruitment. Locally, excessive waterlogging strongly filters species able to colonize from regional pools. On the other hand, increased water availability can accommodate a rich community of drought-sensitive immigrant species that are able to track buffered wetland microclimates. We argue that environmental conditions in many wetlands are not homogeneous with respect to regional climate, and that responses of wetland tree communities to future climate change may lag behind that of non-wetland, terrestrial habitat.

Campomanesia spp. native fruits as potential source of health-promoting compounds

Campomanesia xanthocarpa var. littoralis, Campomanesia xanthocarpa (Berg), and Campomanesia eugenioides are native fruit plants found in Brazil. Due to the scarce number of controlled scientific studies comparing different native Campomanesia species, this study sought to determine their bioactive compounds and antioxidant properties. C. eugenioides proved to be a rich source of total phenolic compounds, also showing the best antioxidant capacity by the ABTS, DPPH and molybdenum reduction power methods. On the other hand, C. xanthocarpa var. littoralis showed the best results for total flavonoids content, and Iron(II) chelation power. The phenolic compounds contents present in C. eugenioides could be responsible for the best antioxidant activity. This study provides key scientific data regarding the use of valuable fruits from different edible Campomanesia species to produce bioactive ingredients, as well as natural preservatives for food products. Thus, our results contribute to the discovery of the potential application of these native Campomanesia Brazilian fruits, as a natural product with functional and antioxidant properties.