Demographic composition, not demographic diversity, predicts biomass and turnover across temperate and tropical forests.

The growth and survival of individual trees determine the physical structure of a forest with important consequences for forest function. However, given the diversity of tree species and forest biomes, quantifying the multitude of demographic strategies within and across forests and the way that they translate into forest structure and function remains a significant challenge. Here, we quantify the demographic rates of 1961 tree species from temperate and tropical forests and evaluate how demographic diversity (DD) and demographic composition (DC) differ across forests, and how these differences in demography relate to species richness, aboveground biomass (AGB), and carbon residence time. We find wide variation in DD and DC across forest plots, patterns that are not explained by species richness or climate variables alone. There is no evidence that DD has an effect on either AGB or carbon residence time. Rather, the DC of forests, specifically the relative abundance of large statured species, predicted both biomass and carbon residence time. Our results demonstrate the distinct DCs of globally distributed forests, reflecting biogeography, recent history, and current plot conditions. Linking the DC of forests to resilience or vulnerability to climate change, will improve the precision and accuracy of predictions of future forest composition, structure, and function.

Beginnings of a plant parasite: early development of Rafflesia consueloae inside its Tetrastigma host.

MAIN CONCLUSION: Extensive histology of host organs revealed the early events in the vegetative growth of Rafflesia consueloae including initial infection site, endophyte distribution, and other developmental events prior to bud emergence. The early events in the vegetative development of the holoparasite Rafflesia have long remained a mystery. Because its entire vegetative growth occurs within the host body, very little is known about the developmental events prior to emergence of the floral shoot. The goal of this study was to describe the events that occur during the vegetative growth of R. consueloae, particularly in the early stages of infection. We performed extensive microtome sectioning of multiple root and stem segments from different Tetrastigma host individuals to examine the cytology, distribution, and development of the R. consueloae endophyte within the host tissues. We found that R. consueloae infection is restricted to the roots of its host. Infection begins within the vascular cambium where the endophyte appears to initially reside prior to their radial spread to the vascular tissues. The tissues obtained from different host individuals had varying degrees of infection alluding to a possible role of host resistance mechanisms and/or varying levels of parasite infectiousness. Endophyte presence in host vines without external manifestations of infection indicates that the parasite may dwell within the host tissues for prolonged periods as small cell clusters without transitioning to the reproductive stage. Furthermore, we found that floral shoots may develop in scarcely infected host tissues indicating that extensive endophyte growth within the host is not a prerequisite to the onset of reproductive development. Overall, our study describes for the first time the developmental events prior to emergence of R. consueloae buds from its host.

RecruitNet: A global database of plant recruitment networks.

Plant recruitment interactions (i.e., what recruits under what) shape the composition, diversity, and structure of plant communities. Despite the huge body of knowledge on the mechanisms underlying recruitment interactions among species, we still know little about the structure of the recruitment networks emerging in ecological communities. Modeling and analyzing the community-level structure of plant recruitment interactions as a complex network can provide relevant information on ecological and evolutionary processes acting both at the species and ecosystem levels. We report a data set containing 143 plant recruitment networks in 23 countries across five continents, including temperate and tropical ecosystems. Each network identifies the species under which another species recruits. All networks report the number of recruits (i.e., individuals) per species. The data set includes >850,000 recruiting individuals involved in 118,411 paired interactions among 3318 vascular plant species across the globe. The cover of canopy species and open ground is also provided. Three sampling protocols were used: (1) The Recruitment Network (RN) protocol (106 networks) focuses on interactions among established plants ("canopy species") and plants in their early stages of recruitment ("recruit species"). A series of plots was delimited within a locality, and all the individuals recruiting and their canopy species were identified; (2) The paired Canopy-Open (pCO) protocol (26 networks) consists in locating a potential canopy plant and identifying recruiting individuals under the canopy and in a nearby open space of the same area; (3) The Georeferenced plot (GP) protocol (11 networks) consists in using information from georeferenced individual plants in large plots to infer canopy-recruit interactions. Some networks incorporate data for both herbs and woody species, whereas others focus exclusively on woody species. The location of each study site, geographical coordinates, country, locality, responsible author, sampling dates, sampling method, and life habits of both canopy and recruit species are provided. This database will allow researchers to test ecological, biogeographical, and evolutionary hypotheses related to plant recruitment interactions. There are no copyright restrictions on the data set; please cite this data paper when using these data in publications.

Medinillatheresae (Melastomataceae), a new species from ultramafic soils in the Philippines.

A new species, Medinillatheresae Fernando, from ultramafic soils on Dinagat and Mindanao Islands, Philippines is described and illustrated. The species is characterized by its terrestrial erect habit, non-setose nodes, 3-plinerved, lanceolate and coriaceous leaves arranged in whorls, cauline or axillary and pendulous inflorescences, rounded flower buds, 4-merous flowers, and straight anthers. It is compared with other similar species in the Medinillapendula Merr. complex.

Rafflesia consueloae (Rafflesiaceae), the smallest among giants; a new species from Luzon Island, Philippines.

A new species of Rafflesia (Rafflesiaceae) from Luzon Island, Philippines, Rafflesia consueloae Galindon, Ong & Fernando, is described and illustrated. It is distinct from all other species of Rafflesia in its small-sized flowers, the upright perigone lobes, and prominently cream-white disk surface that is often devoid of processes. Its small-sized flowers, with an average diameter of 9.73 cm when fully expanded, make it the smallest of the largest flowers in the world.

Rinorea niccolifera (Violaceae), a new, nickel-hyperaccumulating species from Luzon Island, Philippines.

A new, nickel-hyperaccumulating species of Rinorea (Violaceae), Rinorea niccolifera Fernando, from Luzon Island, Philippines, is described and illustrated. This species is most similar to the widespread Rinorea bengalensis by its fasciculate inflorescences and smooth subglobose fruits with 3 seeds, but it differs by its glabrous ovary with shorter style (5 mm long), the summit of the staminal tube sinuate to entire and the outer surface smooth, generally smaller leaves (3-8 cm long × 2-3 cm wide), and smaller fruits (0.6-0.8 cm diameter). Rinorea niccolifera accumulates to >18,000 µg g(-1) of nickel in its leaf tissues and is thus regarded as a Ni hyperaccumulator.

The loss of species: mangrove extinction risk and geographic areas of global concern.

Mangrove species are uniquely adapted to tropical and subtropical coasts, and although relatively low in number of species, mangrove forests provide at least US $1.6 billion each year in ecosystem services and support coastal livelihoods worldwide. Globally, mangrove areas are declining rapidly as they are cleared for coastal development and aquaculture and logged for timber and fuel production. Little is known about the effects of mangrove area loss on individual mangrove species and local or regional populations. To address this gap, species-specific information on global distribution, population status, life history traits, and major threats were compiled for each of the 70 known species of mangroves. Each species' probability of extinction was assessed under the Categories and Criteria of the IUCN Red List of Threatened Species. Eleven of the 70 mangrove species (16%) are at elevated threat of extinction. Particular areas of geographical concern include the Atlantic and Pacific coasts of Central America, where as many as 40% of mangroves species present are threatened with extinction. Across the globe, mangrove species found primarily in the high intertidal and upstream estuarine zones, which often have specific freshwater requirements and patchy distributions, are the most threatened because they are often the first cleared for development of aquaculture and agriculture. The loss of mangrove species will have devastating economic and environmental consequences for coastal communities, especially in those areas with low mangrove diversity and high mangrove area or species loss. Several species at high risk of extinction may disappear well before the next decade if existing protective measures are not enforced.

Homoplasious character combinations and generic delimitation: a case study from the Indo-Pacific arecoid palms (Arecaceae: Areceae).

The complex distributions of morphological character states in the Indo-Pacific palm tribe Areceae (Arecaceae; Arecoideae) are potentially challenging for the delimitation of its genera. In the first exhaustive sampling of all 65 genera of the Areceae, we examined relationships of two of the tribe's most problematic genera, Heterospathe and Rhopaloblaste, using portions of the low-copy nuclear genes phosphoribulokinase (PRK) and RNA-polymerase II subunit B (RPB2). Both genera fell within a highly supported clade comprising all Areceae genera, but are clearly unrelated. Rhopaloblaste was strongly supported as monophyletic and is most closely related to Indian Ocean genera. Heterospathe was resolved with strong support within a clade of western Pacific genera, but with the monotypic Alsmithia nested within it. Ptychosperma micranthum, which has previously been included in both Heterospathe and Rhopaloblaste, is excluded from these and from Ptychosperma, supporting its recent placement in a new genus Dransfieldia. Morphological comparisons indicate that the crownshaft is putatively synapomorphic for the Areceae with numerous reversals within the clade and some independent origins elsewhere. The putative diagnostic characters of Heterospathe show high levels of homoplasy, and the genus can only be distinguished by a suite of characters, whereas Rhopaloblaste is more clearly defined. Our results have implications not only for the two genera in focus, but have also been influential for the new classification of the Areceae.