Scott A. Mori

A spatial model of tree α-diversity and tree density for the Amazon

Large-scale patterns of Amazonian biodiversity have until now been obscured by a sparse and scattered inventory record. Here we present the first comprehensive spatial model of tree α-diversity and tree density in Amazonian rainforests, based on the largest-yet compilation of forest inventories and bolstered by a spatial interpolation technique that allows us to estimate diversity and density in areas that have never been inventoried. These data were then compared to continent-wide patterns of rainfall seasonality. We find that dry season length, while only weakly correlated with average tree α-diversity, is a strong predictor of tree density and of maximum tree α-diversity. The most diverse forests for any given DSL are concentrated in a narrow latitudinal band just south of the equator, while the least diverse forests for any given DSL are found in the Guayana Shield and Amazonian Bolivia. Denser forests are more diverse than sparser forests, even when we used a measure of diversity that corrects for sample size. We propose that rainfall seasonality regulates tree α-diversity and tree density by affecting shade tolerance and subsequently the number of different functional types of trees that can persist in an area.

An analysis of the floristic composition and diversity of Amazonian forests including those of the Guiana Shield.

A large number of newly published and unpublished hectare plots in Amazonia and the Guiana Shield area allow an analysis of family composition and testing of hypotheses concerning alpha-diversity in the south American rain forest. Using data from 94 plots the family-level floristic patterns in wet tropical South America are described. To test diversity patterns, 268 plots are used in this large area. Contrary to a widely held belief, western Amazonian plots are not necessarily the most diverse. Several central Amazonian plots have equal or even higher tree diversity. Annual rainfall is not a good estimator for tree diversity in the Amazonia area and Guiana shield. Plots in the Guiana Shield area (and eastern Amazonia) usually have lower diversity than those in central or western Amazonia. It is argued that this is not because of low rainfall or low nutrient status of the soil but because of the small area of the relatively isolated rain forest area in eastern Amazonia and the Guiana Shield. The low diversity on nutrient-poor white sand soils in the

Southern Bahian moist forests

The moist forests of southern Bahia, although occupying less than 10% of the original cover, represent one of the last strongholds of lowland forest in eastern Brazil. Friedrich Sellow (1815) and K. F. P. von Martius (1818) were the first botanists to make significant collections in the region, a tradition which has been intensified by the efforts of the staff of the herbarium of the “Centro de Pesquisas do Cacau” (CEPEC) from 1965 to the present. The climate is hot and humid with 1200–1800 mm of rainfall evenly distributed throughout the year. These conditions are ideal for the cultivation of cocoa (Theobroma cacao L.), the principal crop of the region. The native forests are related structurally and in taxonomic composition to those of Amazonia and possess a high degree of endemism. Buttresses (17% of the trees), latex (20% of the trees), and mesophyll leaves with entire margins characterize the trees which are present in densities of 891.26 individuals over 10 cm DBH/hectare. Densities, frequencies, dominances, and importance values, based on a study of 600 trees, are given for the 178 species of trees found at a study site located near Buerarema, Bahia. Only 0.3% of the trees studied fell in the 80–89 cm size class whereas 95.5% were in size classes below 50 cm DBH. The forest appears to be stratified into lower, canopy, and emergent layers. Epiphytes (on 80% of trees) and lianas (on 37.5% of trees) are common. Trees flower throughout the year but exhibit a definite peak of flowering in the spring (October to December) which is probably a response to increase in daylength and/or temperature. Leaf fall and leaf flush are also more prevalent in the spring. The five most important families in terms of diversity, density, and dominance are: Myrtaceae, Sapotaceae, Caesalpiniaceae, Lauraceae, and Chrysobalanaceae. A species list, based on the collections of the CEPEC herbarium, is included. Protected areas, in this rapidly disappearing vegetation type, represent only 0.1% of the original forest.ResumoAs matas higrófilas e mesófilas do sul da Bahia, embora que ocupam menos de 10% da cobertura original, representam uma das últimas reservas deste tipo de mata no leste do Brasil. Friedrich Sellow (1815) e K. F. P. von Martius (1818) foram os primeiros a colher amostras botânicas na região, uma tradição que tem sido intensificada desde 1965 pelo pessoal do Centro de Pesquisas do Cacau (CEPEC). O clima onde ocorre estas matas é quente e úmido com os 1200 a 1800 mm de chuva média anual distribuída igualmente por todo o ano, assim apresentando condições ideais para o cultivo de cacau (Theobroma cacao L.), a safra principal da região. A estructura da mata e a sua composição florística correspondem com as da mata amazônica. Raízes tabulares (em 17% das árvores), latex (em 20% das árvores) e folhas mesófilas com bordos inteiros caracterizam as árvores que estão presentes em densidade de 891,26/hectare. Densidades, freqüências, dominâncias, valores de importância, baseados num estudo de 600 árvores, são dados para as 178 espécies de árvores encontradas no local do estudo, situado próximo à Buerarema, Bahia. Sòmente 0,3% destas árvores apareceram na classe de diâmetro de 80–89 cm enquanto que 95,5% cairam em classes abaixo de 50 cm DAP. A mata é aparentemente estratificada em três níveis de árvores, e epífitas (sobre 80% das árvores) e cipós (sobre 37,5% das árvores) estão comuns. Hão espécies de árvores que florescem em todas as épocas do ano, mas existe um pico definido de floração na primavera, que está, provavelmente, relacionado com o aumento no comprimento do dia e/ou temperatura. Queda e lançamento de folhas também prevalecem na primavera. As cinco famílias de árvores mais importantes em termos de diversidade, densidade, e dominância são Myrtaceae, Sapotaceae, Caesalpiniaceae, Lauraceae, e Chrysobalanaceae. Uma lista de espécies, baseada na coleção do herbário do CEPEC, é incluída. Áreas protegidas em forma de parques nacionais ou reservas ecológicas representam sòmente 0, 1% da mata original da região.

A central Amazonian terra firme forest. I. High tree species richness on poor soils

Tree size, density, and species richness were established for three one-hectare plots of terra firme forest in central Amazonian Brazil. In the three hectares, 1916 individual trees with DBH 10 ≥ cm were sampled. A total of 58 families, 181 genera, and 513 species were determined. Hectare A had 285 species, 138 genera, and 47 families; hectare B 280 species, 123 genera, and 48 families; and hectare C 280 species, 125 genera, and 44 families. Comparably high species richness in Amazonia has heretofore only been reported from western Amazonia. This dispels the idea that high species richness can only develop in areas with rich soils and relatively high rainfall. It is suggested that such high species richness is the result of a combination of habitat heterogeneity and geological history. These high diversity forests, because they occur on nutrient poor soils, can be protected with little or no impact on development in the region because the soils are essentially useless for agriculture and for supporting long-term cattle pasture.

Distribution patterns and conservation of eastern Brazilian coastal forest tree species

The distributions of 127 tree species, each with at least part of their range in the moist coastal forest of eastern Brazil, are analyzed. Of these, 53.5% are endemic to the coastal forest, 11.8% endemic to the coastal forest plus some part of the Planalto of Brazil, 7.8% disjunct with the Amazonian hylaea, and 26% widespread. This high endemism in the coastal forest of eastern Brazil, in view of its rapid destruction, emphasizes the need for increased preservation of the few remaining natural areas. In addition, this study supports the theory that there are at least two centers of endemism in the coastal forests, one centering around Rio de Janeiro and one in southern Bahia/Rio Doce, Espírito Santo. In order to protect the diverse flora of the coastal forests, preservation areas should be established intermittently along their entire length and especially in the centers of endemism.

Identification of Amazonian Trees with DNA Barcodes

Background Large-scale plant diversity inventories are critical to develop informed conservation strategies. However, the workload required for classic taxonomic surveys remains high and is particularly problematic for megadiverse tropical forests. Methodology/Principal Findings Based on a comprehensive census of all trees in two hectares of a tropical forest in French Guiana, we examined whether plant DNA barcoding could contribute to increasing the quality and the pace of tropical plant biodiversity surveys. Of the eight plant DNA markers we tested (rbcLa, rpoC1, rpoB, matK, ycf5, trnL, psbA-trnH, ITS), matK and ITS had a low rate of sequencing success. More critically, none of the plastid markers achieved a rate of correct plant identification greater than 70%, either alone or combined. The performance of all barcoding markers was noticeably low in few species-rich clades, such as the Laureae, and the Sapotaceae. A field test of the approach enabled us to detect 130 molecular operational taxonomic units in a sample of 252 juvenile trees. Including molecular markers increased the identification rate of juveniles from 72% (morphology alone) to 96% (morphology and molecular) of the individuals assigned to a known tree taxon. Conclusion/Significance We conclude that while DNA barcoding is an invaluable tool for detecting errors in identifications and for identifying plants at juvenile stages, its limited ability to identify collections will constrain the practical implementation of DNA-based tropical plant biodiversity programs.

Cecropia as a food resource for bats in French Guiana and the significance of fruit structure in seed dispersal and longevity.

Cecropia (Cecropiaceae) is a Neotropical genus of pioneer plants. A review of bat/plant dispersal interactions revealed that 15 species of Cecropia are consumed by 32 species of bats. In French Guiana, bats were captured in primary and secondary forests, yielding 936 fecal samples with diaspores, among which 162 contained fruits of C. obtusa, C. palmata, and C. sciadophylla. A comparative morphological and anatomical study of fruits and seeds taken directly from herbarium specimens, bat feces, and an experimental soil seed bank was made. Contrary to previous reports, the dispersal unit of Cecropia is the fruit not the seed. Bats consume the infructescence, digest pulp derived from the enlarged, fleshy perianth, and defecate the fruits. The mucilaginous pericarp of Cecropia is described. The external mucilage production of Cecropia may facilitate endozoochory. The exocarp and part of the mesocarp may be lost after passage through the digestive tract of bats, but fruits buried for a year in the soil seed bank remain structurally unchanged. Fruit characters were found to be useful for identifying species of bat-dispersed Cecropia. Bat dispersal is not necessary for seed germination but it increases seed survival and subsequent germination. Fruit structure plays a significant role in seed longevity.

Phylogenetic relationships of Lecythidaceae: a cladistic analysis using rbcL sequence and morphological data.

This study examined in detail the rbcL sequence and morphological support for subfamilial relationships and monophyly of Lecythidaceae. Initially we needed to establish relationships of Lecythidaceae among other dicot families. To complete this we examined 47 rbcL sequences of 25 families along with molecular observations from several large analyses of rbcL data. All analyses strongly support the monophyly of the asterid III grouping. This analysis revealed Lecythidaceae to be paraphyletic and indicated potential outgroup relationships with Sapotaceae. Once relationships had been evaluated using molecular data we then concentrated on analyzing separate and combined morphological and molecular databases. The topology of the morphological data set was similar to the rbcL sequence and combined data sets except for the positioning of Napoleonaeoideae, Grias, Gustavia, and Oubanguia. According to the combined results, Planchonioideae, Lecythidoideae. and Foetidioideae are monophyletic, whereas the subfamily Napoleonaeoideae are paraphyletic. Nested within Napolconaeoideae, we found Asteronthos forms a strongly supported clade with Oubanguia (Scytopetalaceae). Foetidia, the only genus of Foetidioideae, is sister to Planchonioideae, and this clade is sister to Lecythidoideae. The [(Planchonioideae, Foetidioideae) Lecythidoideae are sister to Asteranthos/Oubanguia. Napoleonaeoideae are sister to the rest of Lecythidaceae.

Evolution of Lecythidaceae with an emphasis on the circumscription of neotropical genera: information from combined ndhF and trnL-F sequence data

The Lecythidaceae comprise a pantropical family best known for the edible seeds of the Brazil nut (Bertholletia excelsa) and the cannon-ball tree (Couroupita guianensis), which is planted as a botanical curiosity in subtropical and tropical gardens. In addition, species of the family are often among the most common in neotropical forests, especially in the Amazon Basin. The Brazil nut family is diverse and abundant in the Amazon and is considered to be an indicator of undisturbed or scarcely disturbed lowland forests; thus, what is learned about its evolution, ecology, and biogeography may suggest similar patterns for other Amazonian tree families. We used combined data sets derived from the ndhF and trnL-F genes to elucidate relationships of genera in both the Old and New Worlds that have been associated with Lecythidaceae. Our molecular tree agrees with the recognition of Napoleonaeaceae and Scytopetalaceae. Within the Lecythidaceae, there is molecular support for recognizing three subfamilies: Foetidioideae, Planchonioideae, and Lecythidoideae. We then focused on genera of the Lecythidoideae and found support for recognizing Allantoma (when the actinomorphic-flowered species of Cariniana are included in it), Grias, Gustavia, Corythophora, Couratari, and Couroupita, but conclude that Cariniana, Lecythis, and Eschweilera are not monoyphyletic. Because the position of the monotypic Bertholletia excelsa in relation to the other zygomorphic-flowered genera is not resolved, we are not able to comment on its generic relationships.

USING AMPLIFIED FRAGMENT LENGTH POLYMORPHISMS (AFLP) TO IDENTIFY BLACK COHOSH (ACTAEA RACEMOSA) 1

The rhizome ofActaea racemosa L., commonly called black cohosh, is a popular botanical dietary supplement used to treat female health concerns. The rhizomes used in black cohosh products are often collected from the wild. To ensure quality control, it is imperative that plants be correctly identified. This paper examines the use of the DNA fingerprinting technique, AFLP, as an analytical means of identifyingA. racemosa from three other closely related sympatric species. To this end, 262 AFLP markers were generated, and one unique fingerprint was identified forA. racemosa, whereas two, six, and eight unique fingerprints were identified for the closely related speciesA. pachypoda, A. cordifolia, andA. podocarpa, respectively. Two commercial black cohosh products were also subjected to AFLP analysis and shown to contain onlyA. racemosa. The results of this study suggest that AFLP analysis may offer a useful method for quality control in the botanical dietary supplements industry.ResumenDas Rhizom vonActaea racemosa L., allgemein als ‘black cohosh’ bezeichnet, ist eine beliebte pflanzliche Diätsergänzung, die für weibliche Gesundheitsprobleme benützt wird. Oft sind die in ‘black cohosh’-Produkten verwendeten Rhizome in freier Natur gesammelt. Um Qualitätskontrolle zu sichern, ist es zwingend, die Pflanzen richtig zu identifizieren. Diese Studie überprüft den Gebrauch der DNA-Fingerabdrucktechnik, AFLP, als analytisches Mittel der Identifizierung, umA. racemosa von drei anderen in ihrer Nähe beheimateten und nah verwandten Spezies zuunterscheiden. Zu diesem Zweck wurden 262 AFLP-Fingerabdrücke erzeugt. Für A. racemosa wurde ein einzigartiger Fingerabdruck identifiziert, während für die nah verwandten Spezies A. pachypoda zwei, A. cordifolia sechs, und A. podocarpa acht einzigartige Fingerabdrücke gefunden wurden. Zwei kommerzielle ‘black cohosh’ -Produkte wurden ebenfalls der AFLP-Analyse unterzogen, wobei nur A. racemosa nachgewiesen werden konnte. Die Resultate dieser Studie zeigen, daβ die AFLP-Technik eine nützliche Methode für die Qualitdtskontrolle in der pflanzlichen Diätsergänzungsindustrie bieten kann.