Strong floristic distinctiveness across Neotropical successional forests

Forests that regrow naturally on abandoned fields are important for restoring biodiversity and ecosystem services, but can they also preserve the distinct regional tree floras? Using the floristic composition of 1215 early successional forests (≤20 years) in 75 human-modified landscapes across the Neotropic realm, we identified 14 distinct floristic groups, with a between-group dissimilarity of 0.97. Floristic groups were associated with location, bioregions, soil pH, temperature seasonality, and water availability. Hence, there is large continental-scale variation in the species composition of early successional forests, which is mainly associated with biogeographic and environmental factors but not with human disturbance indicators. This floristic distinctiveness is partially driven by regionally restricted species belonging to widespread genera. Early secondary forests contribute therefore to restoring and conserving the distinctiveness of bioregions across the Neotropical realm, and forest restoration initiatives should use local species to assure that these distinct floras are maintained

Biogeographical patterns of liana abundance and diversity

This chapter examines the pantropical patterns of liana abundance and species diversity and their correlates with climatic characteristics to gain insight into which processes are important for the distribution of tropical lianas. The analyses follow from the standard sampling protocol of liana diversity and abundance used by Alwyn Gentry in the 1980s and 1990s. The chapter examines how climatic conditions are associated with liana density and diversity, by analyzing old-growth continental forests at 850mm yr-1.To broaden the discussion of determinants of liana density and diversity beyond climatic factors, the authors comment on differences between temperate and tropical forests and between continental and island regions. The chapter focuses on sites in the Global Liana Database (GLD) from temperate forests in Australia, subtropical forest in Argentina, and an island in the Caribbean, and also reviews the available literature

Ethnobotany of the Tacana : quantitative inventories of two permanent plots of northwestern Bolivia

We present ecological and ethnobotanical descriptions of two permanent 1-ha plots located in Amazonian forest near two Tacana communities situated north and west of the Madidi National Park in the Iturralde Province, Department of La Paz of northwestern Bolivia. We interviewed 13 Tacana men and women to identify and enumerate uses of all of the trees, palms, and lianas >- 10 cm dbh in these plots. Of the 185 species found in both plots, 115 species are used by the Tacana. 59 species for constructin, 9 as sources of fiber, 33 for technology and crafts, 66 as firewood, 32 for food or water, 40 for medicine, 8 for hunting or fishing, 9 for commercial purposes, and 11 for miscellaneous uses. Sixty-four percent of useful species had multiple uses. This utilization of the forest corresponds with that of other Amazonian indigenous groups and shows a high reliance on the forest for vegetative materials, especially medicine, technology and crafts, and construction

Ethnobotany of the Tacana : quantitative inventories of two permanent plots of northwestern Bolivia

We present ecological and ethnobotanical descriptions of two permanent 1-ha plots located in Amazonian forest near two Tacana communities situated north and west of the Madidi National Park in the Iturralde Province, Department of La Paz of northwestern Bolivia. We interviewed 13 Tacana men and women to identify and enumerate uses of all of the trees, palms, and lianas >- 10 cm dbh in these plots. Of the 185 species found in both plots, 115 species are used by the Tacana. 59 species for constructin, 9 as sources of fiber, 33 for technology and crafts, 66 as firewood, 32 for food or water, 40 for medicine, 8 for hunting or fishing, 9 for commercial purposes, and 11 for miscellaneous uses. Sixty-four percent of useful species had multiple uses. This utilization of the forest corresponds with that of other Amazonian indigenous groups and shows a high reliance on the forest for vegetative materials, especially medicine, technology and crafts, and construction

Decomposition in tropical forests: a pan-tropical study of the effects of litter type, litter placement and mesofaunal exclusion across a rainfall gradient

1. Litter decomposition recycles nutrients and causes large fluxes of carbon dioxide into the atmosphere. It is typically assumed that climate, litter quality and decomposer communities determine litter decay rates, yet few comparative studies have examined their relative contributions in tropical forests. 2. We used a short-term litterbag experiment to quantify the effects of litter quality, placement and mesofaunal exclusion on decomposition in 23 tropical forests in 14 countries. Annual precipitation varied among sites (760¿5797 mm). At each site, two standard substrates (Raphia farinifera and Laurus nobilis) were decomposed in fine- and coarse-mesh litterbags both above and below ground for approximately 1 year. 3. Decomposition was rapid, with >95% mass loss within a year at most sites. Litter quality, placement and mesofaunal exclusion all independently affected decomposition, but the magnitude depended upon site. Both the average decomposition rate at each site and the ratio of above- to below-ground decay increased linearly with annual precipitation, explaining 60¿65% of among-site variation. Excluding mesofauna had the largest impact on decomposition, reducing decomposition rates by half on average, but the magnitude of decrease was largely independent of climate. This suggests that the decomposer community might play an important role in explaining patterns of decomposition among sites. Which litter type decomposed fastest varied by site, but was not related to climate. 4. Synthesis. A key goal of ecology is to identify general patterns across ecological communities, as well as relevant site-specific details to understand local dynamics. Our pan-tropical study shows that certain aspects of decomposition, including average decomposition rates and the ratio of above- to below-ground decomposition are highly correlated with a simple climatic index: mean annual precipitation. However, we found no relationship between precipitation and effects of mesofaunal exclusion or litter type, suggesting that site-specific details may also be required to understand how these factors affect decomposition at local scale