bluuebunny/crossref_metadata_2025_split huggingface dataset:
Disease of Red Mangrove (Rhizophora mangley) in Southwest Puerto Rico Caused by Cytospora rhizophorae1
Authors: Wier Andrew M. , Tattar Terry A. , Klekowski Edward J. 
Published: March 2006

ABSTRACTA high frequency of dieback and mortality was found in Rhizophora mangle (red mangrove) in coastal mangrove forests of southwest Puerto Rico. Eight plots were established in a variety of mangrove environments to assess the extent and severity of the dieback and mortality. The imperfect fungus Cytospora rhizopborae was isolated consistently from stem dieback and associated canker tissues. No other pathogenic microorganisms were isolated. Pathogenicity was demonstrated in greenhouse and field inoculation experiments with C. rhizophorae using young R. mangle seedlings. In field studies of seedlings inoculated, mortality was 33 percent, and greenhouse mortality was as high as 50 percent. Cytospora rhizophorae was isolated consistently from diseased mangrove tissue; the fungus was grown in pure culture and then inoculated into healthy red mangroves, causing cankers. Koch's postulates were fulfilled by infecting R. mangle with C. rhizophorae, producing disease symptoms, and successfully re‐isolating C. rhizophorae from the diseased tissue. This is the first documentation of the pathogenicity of C. rhizophorae associated with mortality in red mangrove. In the coastal mangrove forests of southwest Puerto Rico, C. rhizophorae may play an important role in the frequency of dieback and mortality in R. mangle, producing slow stem diameter growth and causing frequent stem and root wounds.
Difference in Intensity of Ant Defense among Three Species ofMacarangaMyrmecophytes in a Southeast Asian Dipterocarp Forest1
Authors: Itioka Takao , Nomura Masahiro , Inui Yoko , Itino Takao , Inoue Tamiji 
Published: March 2006

ABSTRACTTo examine interspecific variation in the intensity of ant defense among three sympatric species of obligate myrme‐cophytes ofMacaranga(Euphorbiaceae), we measured the ratio of ant biomass to plant biomass, ant aggressiveness to artificial damage on host plants, and increase in herbivore damage on host plants when symbiont ants were removed. Increase in herbivore damage from two‐ and four‐week ant exclusion varied significantly among the three species. The decreasing order of vulnerability to herbivory wasM. winkleri, M. trachyphylla, andM. beccariana.The antip/ant biomass ratio (= rate of the dry weight of whole ant colonies to the dry weight of whole aboveground plant parts) and ant agressiveness also varied significantly among the three species; the orders of both the ant/plant biomass ratio and ant aggressiveness were the same as in the herbivory increase. These results indicated that the intensity of ant defense differs predictably among sympatric species of obligate myrmecophytes onMacaranga.In addition to the interspecific difference in the total intensity of ant defense, when symbiont ants were excluded, both patterns of within‐plant variation in the amount of herbivore damage and compositions of herbivore species that caused the damage differed among species. This suggests that the threeMacarangaspecies have different systems of ant defense with reference to what parts of plant tissue are protected and what herbivorous species are avoided by ant defense. Thus, it is important to consider the interspecific variation in ant defense amongMacarangaspecies to understand the herbivore community onMacarangaplants and the mechanisms that promote the coexistence of multipleMacarangamyrmecophytes.
Seed Dispersal of a High Quality Fruit by Specialized Frugivores: High Quality Dispersal?1
Authors: Wenny Daniel G. 
Published: March 2006

ABSTRACTDispersal quality, as estimated by the cumulative effects of dispersal, germination, seed predation, and seedling survival, was examined for Beilschmiedia pendula (Lauraceae) in Monteverde, Costa Rica. I determined the pattern of dispersal by finding seeds deposited by birds, protected the seeds from seed predators with cages to assess germination and seedling survival, and examined seed predation rates with marked seeds. Seed predation, germination, and seedling survival were compared between seeds naturally dispersed by birds and seeds placed at randomly located sites.Approximately 70 percent of seeds dispersed by birds (N= 244) were deposited <10 m from crown edges of fruiting B. pendula trees, although some seeds were dispersed at least 70 m away. Larger seeds were more likely to be dispersed under or close to the parent trees, and larger seeds produced larger seedlings. Seed size was not correlated directly with seedling survival, but larger seedlings at three months were most likely to survive one year. Seed predation by mammals and insects and seedling mortality due to fungal pathogens were concentrated beneath the crowns of parent trees. Seedlings and saplings were more abundant beneath fruiting B. pendula trees, but individuals farther away were taller on average. Thus, dispersal is beneficial for B. pendula, but such benefits appear most pronounced at a small spatial scale; seeds dispersed >30 m from the crown edges actually had a lower probability of survival than those dispersed 10–20 m. Only 10 percent of B. pendula. seeds received high‐quality dispersal in terms of landing in the zone with the highest per seed probability of seedling survival 10–20 m from parental crowns.
Spatial Distribution of Vascular Epiphytes (including Hemiepiphytes) in a Lowland Amazonian Rain Forest (Surumoni Crane Plot) of Southern Venezuela1
Authors: Nieder Jürgen , Engwald Stefan , Klawun Martin , Barthlott Wilhelm 
Published: March 2006

ABSTRACTThe mobile crane of the Surumoni project allowed for the first time ever a complete inventory and spatial description of the epiphytic vegetation of a tropical lowland rain forest plot (1.5 ha), at La Esmeralda on the upper Orinoco River, Venezuela. A total of 778 individual vascular epiphytes of 53 species was found, dominated by 19 orchid species and 14 species of Araceae. Fifty percent of all individual plants were obligate ant‐garden epiphytes. The distribution of epiphytes was highly clumped and not random. The clumped occurrence of holoepiphytes (complete life cycle on host tree) was the consequence of the rarity of suitable phorophytes (host trees;e.g., size and age) in the plot and the preference of ants for gaps where most of the ant‐garden epiphytes were found. In comparison, hemiepiphytes were distributed more evenly because of greater independence from tree suitability. The dispersal modes of epiphytes did not explain their distribution patterns. There was no consistent difference in distribution between anemochorous and zoochorous epiphytes, presumably because availability of suitable substrate is the more important factor for epiphyte establishment and growth. Whereas the vertical distribution of epiphytes could be attributed largely to deterministic factors such as physiological adaptation and requirements, horizontal distribution appeared to be governed by suitable substrate, which in turn seemed to be governed by stochastic gap formation.
Estudio Fenológico de Cactíceas en el Enclave Seco de la Tatacoa, Colombia1
Authors: Ruiz Adriana , Santos Mery , Cavelier Jaime , Soriano Pascual J. 
Published: March 2006

RESUMENDurance un año se realizó el estudio fenológico de tres cactáceas columnares Stenocereus griseus (Haw.) Britton & Rose, Pilosocereus sp., Cereus hexagonus (L.) Mill., y una cactácea decumbente, Monvillea cf. smithiana (Britton & Rose) Backeberg., en el enclave seco interandino de La Tatacoa, Colombia. Los polinizadores y/o dispersores de las cactáceas fueron capturados mensualmente y se recolectaron las muestras fecales para la identificatión de los granos de polen y las semillas de los frutos consumidos. La floración de todas las especies fue prolongada y mostraron patrones bimodales, multimodales, o irregulares. La fructificación en todas las especies también se extendió durante todo el año, con un desfase de dos meses con respecto a la floración. Aunque no se encontró una correlatión significativa entre los valores mensuales de precipitatión y la producción de flores y frutos, la floración durante la época seca fue mayor en S. griseus, mientras que Pilosocereus sp. y C. hexagonus mostraron los valores más altos durante la época de lluvias. La productión de frutos también fue estacional, con un incremento durante la época de lluvias para S. griseus y C. hexagonus. La floración y fructificatión en M. cf. smithiana no mostraron diferencias significativas entre la época seca y la lluviosa. Los murciélagos Glossophaga longirostris, Carollia perspicillata, Sturnira lilium y algunas aves como Melanerpes rubricapillus (Picidae) y Mimus gilvus (Mimidae), y una mariposa nocturna (Sphingidae), fueron algunos de los polinizadores y/o consumidores de estas especies de cactáceas.
Quetzal Abundance in Relation to Fruit Availability in a Cloud Forest in Southeastern Mexico1
Authors: Solórzano Sofía , Castillo Silvia , Valverde Teresa , Ívila Lourdes 
Published: March 2006

ABSTRACTThe Resplendent Quetzal(Pharomachrus mocinno)is an altitudinal migrant that nests in high elevation cloud forests and migrates toward lower areas during the summer rainy season. It has been suggested that its migratory movements are related to the abundance of ripe Lauraceae fruits. We studied the quetzal diet during two consecutive years, as well as changes in fruit abundance of the plant species on which the bird feeds at El Triunfo Biosphere Reserve, southeastern Mexico. The quetzal was observed feeding on 32 plant species; of these, 24 are new records in its diet. We chose 20 of these 32 species and studied their fruit phenology for two years in order to describe the relationship between fruit and quetzal abundance. Our results showed that quetzal abundance in the breeding area was correlated with the total number of fruiting species, whereas the correlation between quetzal abundance and the number of fruiting Lauraceae species was only marginal. Additionally, a correlation test showed that quetzal abundance was marginally correlated with total fruit availability (total no. of fruits per month); however, the correlation between quetzal abundance and the number of fruits in the Lauraceae was not significant. Our results suggest that the dynamics of food resources may be playing a major role in the quetzal's migratory behavior. Knowing the bird's diet may aid in characterizing the type of habitat adequate for its conservation. Our observations in this respect suggest that conservation efforts to preserve this bird species should concentrate on the protection of its habitat, including both breeding and nonbreeding (migration) locations.
Patterns of Floristic Differentiation among Atlantic Forests in Southeastern Brazil and the Influence of Climate1
Authors: Oliveira‐Filho Ary T. , Fontes Marco Aurélio L. 
Published: March 2006

ABSTRACTThe tree flora of southeastern Brazilian Atlantic forests was investigated according to two main aspects: (a) the variations in floristic composition of bodi rain and semi‐deciduous forests were analyzed in terms of geographic and climatic variables by performing multivariate analyses on 125 existing floristic checklists; and (b) the links of both rain and semi‐deciduous forests to Amazonian forests and Cerrados (woody savanna) were assessed. All analyses were performed at the species, genus, and family levels. The information obtained for the 125 forest areas was organized into an environmental database containing geographic and climatic records, and a floristic database containing binary presence records for 2532 species, 520 genera, and 106 families. Canonical correspondence analyses (CCA) were utilized to assess the relationship between geographic and climatic variables, and tree flora composition. Venn diagrams and cluster analyses were used to assess the floristic links to Amazonian forests and Cerrados. The following patterns were detected at all three taxonomic levels: (a) the differentiation between rain and semi‐deciduous forests is floristically consistent and strongly correlated with rainfall regime, although transitions may be abrupt to gradual; (b) a north–south differentiation exists for both rain and semi‐deciduous forests, probably caused by variations in both temperature and rainfall regime; (c) The flora of semi‐deciduous forests also changes with increasing distance from the ocean and the associated increasing rainfall seasonality; and (d) elevation and associated temperatures are strongly correlated with the internal differentiation of both rain and semi‐deciduous forests. To a considerable extent, the tree flora of semi‐deciduous forests is a subset of the rain forest flora, probably extracting species that are able to cope with a longer dry season. There is greater floristic similarity at the species level between Atlantic rain and semi‐deciduous forests than between any of these and either Amazonian rain forests or Cerrados. Nevertheless, semi‐deciduous forests and Cerrados show stronger links, particularly at the generic and familial levels. Therefore, rhere is little floristic ground for viewing Atlantic rain forests as being closer to their Amazonian counterparts than to the adjacent semi‐deciduous forests. The most appropriate view of rain and semi‐deciduous forests in southeastern Brazil is that of a continuum in tree species distribution. We suggest that the definition of Atlantic forests should be as comprehensive as that of Amazonian forests.
Hummingbird‐Pollinated Floras at Three Atlantic Forest Sites1
Authors: Buzato Silvana , Sazima Marlies , Sazima Ivan 
Published: March 2006

ABSTRACTWe studied 86 species of hummingbird‐pollinated flowers and their pollinators at a coastal lowland site and two highland rain forest sites in southeastern Brazil. The Jaccard index for hummingbird‐pollinated floras showed greater floristic similarity between the two highland communities than between floras of high altitudes and that of near sea level. The lowland site had slightly greater richness than either of the two highland sites. Bromeliaceae was the most important family, accounting for ca. 36 percent of the bird‐pollinated species and comprising 33 percent of the richest flowers. The plant populations bloomed annually for the most part. Both the wet lowland and the dry highland floras showed flowering seasonality, whereas the cloud highland flora had aseasonal flowering. A hermit hummingbird was the major pollinator in the lowland community. A hermit and a non‐hermit hummingbird shared most of the floral resources in the two highland communities. Hermit hummingbirds are the major pollinators of hummingbird‐pollinated floras in the Atlantic rain forests of southeastern Brazil. These areas may be as rich as Central and other South American areas in hummingbird‐pollinated flowers, and altogether present an older development history when compared to the North American flora.
Reproductive Modes of Atlantic Forest Hylid Frogs: A General Overview and the Description of a New Mode1
Authors: Haddad Célio F. B. , Sawaya Ricardo J. 
Published: March 2006

ABSTRACTThis paper reports a new reproductive mode in anurans, observed for the green treefrog, Hyla leucopygia, a species from the Atlantic Forest of Brazil and a member of the H. albosignata group. The reproductive mode of H. leucopygia is defined as follows: aquatic eggs and embryos in subterranean constructed nests; subsequent to flooding, feeding tadpoles in ponds or streams. We suggest that the new reproductive mode is widespread among the species in the H. albosignata group. The specialized courtship behaviors of H. leucopygia, characterized by vocalizations and a stereotyped sequence of mutual touches between male and female, are described. A review of the reproductive modes of hylid frogs is provided, with 11 modes recognized for the Atlantic Forest hylids and 12 modes for hylids around the world.
Biogeography of South American Forest Mammals: Endemism and Diversity in the Atlantic Forest1
Authors: Costa Leonora Pires , Leite Yuri L. R. , da Fonseca Gustavo A. B. , da Fonseca Mónica Tavares 
Published: March 2006

ABSTRACTWe used parsimony analysis of endemicity (PAE) to investigate the distribution patterns of South American lowland forest mammals, focusing on centers of endemism and diversity. We utilized distribution data available for species of marsupials, rodents, and primates that occur in South America. Two grids were superimposed on the distribution maps: a larger one encompassing tropical and subtropical South America, and a smaller and more precise grid covering the Atlantic Forest only. Also, the number of species per quadrat was estimated. The results support the idea that the distribution of this fauna is structured in the form of centers of endemism. In addition, there is good congruence between the areas identified here and those proposed by other authors, reinforcing the value of PAE in this kind of analysis. The hierarchical relationships among areas, however, are not clear and sometimes discordant with other biogeographic analyses.
The Avifauna of Rio Doce Valley, Southeastern Brazil, a Highly Fragmented Area1
Authors: Machado Ricardo Botnfim , Da Fonseca Gustavo Alberto Bouchardet 
Published: March 2006

ABSTRACTWe analyzed the avifauna from four areas of the Rio Doce basin (the municipal districts of Nova Era [NE], António Dias [AD], Caratinga [BSC], and Marliéria [RDSP]) located in eastern Minas Gerais state. Based on captures with mist nets, 75 bird species belonging to 15 families were inventoried; however, the species composition varied gready among the study areas. Fifty species and 231 of the 466 individuals recorded during this study were captured at NE. In the AD area, 33 species and 132 individuals were captured. The other two areas, BSC and RDSP, contributed only 103 captures and 22 species. By analyzing species composition as a function of altitude of the study areas, it was verified that a variation of 500 m altitude was sufficient in determining the difference in existing bird communities. Formicariidae species, such as Drymophila squamata, Thamnophilus punctatus, and Conopophaga melanops, were captured exclusively in the BSC and RDSP areas, located below the 500 m altitude limit while their congeners (D. ochropyga, T. caerulescens, and C. lineata) were found exclusively in the highest areas (NE and AD). Significant seasonal variations in die species composition were observed (Green's test: Q = 12.79 in NE, 12.84 in AD, 12.4 in BSC, and 20.68 in RDSP; P < 0.05), and we believe that such variations could be associated with seasonal movements between die highest and lowest areas of the Rio Doce basin. As such, the impacts of fragmentation to the Atlantic Forest along this stretch of the Rio Doce basin may have affected the natural dynamics of avian movements. The destruction of > 90 percent of the original Atlantic Forest vegetation cover already may have seriously compromised the population viabilities of birds endemic to this area.
Patch Structure within Brazilian Atlantic Forest Fragments and Implications for Conservation1
Authors: Augusto André , Tabanez Jacinto , Viana Virgilio Maurício 
Published: March 2006

ABSTRACTForest structure and tree species composition were studied in four Atlantic seasonal forest fragments ranging from 0.7 to 220 ha, isolated for more than a century in southeastern Brazil. Four physiognomic units were recognized within these fragments: (1) low forest, (2) bamboo forest, (3) high forest, and (4) mature forest. Tree density, basal area, and species diversity (Shannon‐Wiener index) increased from low forest to bamboo forest to high forest to mature forest. Liana cover was highest in low forest. Gap‐opportunistic species were the dominant ecological group in low forest, bamboo forest, and high forest, while shade tolerant canopy species formed the dominant group in mature forest. These structural and compositional features formed a gradient of forest development from the least developed low and bamboo forests to the most developed mature forest. Low forest is hypothesized to be in a stage of arrested succession and high forest a stage of degraded forest. A conceptual model is suggested to explain how these physiognomic units may be related to one another. Although these fragments were covered mainly by high and low forests and thus had a degraded structure, species diversity remained high in all of them. Fragments thus may undergo degradation long after isolation, even when they have been protected from human disturbance for a considerable period. Nonetheless, they also preserve important samples of local and regional floristic diversity for a long time after isolation.
Tanzanian Forest Edge Microclimatic Gradients: Dynamic Patterns1
Authors: Newmark William D. 
Published: March 2006

ABSTRACTAir temperature, vapor pressure deficit, and light intensity microclimatic gradients were examined along four forest edge and four paired forest interior transects in the East and West Usambara Mountains, Tanzania. Between 14 August 1995 and 11 August 1998, 287, 282, and 196 air temperature, vapor pressure deficit, and light intensity gradients, respectively, were measured along the four forest edge and four interior transects. The relationship between microclimate and distance from the forest edge was examined using piecewise linear regression. All microclimatic gradients were classified into one of nine shapes based on the sign and the size of the two estimated slopes. The relative frequency in the shapes of 65 percent of air temperature gradients, 52 percent of vapor pressure deficit gradients, and 62 percent of light intensity gradients along forest edge transects exceeded the relative frequency of these same shapes along forest interior transects, indicating that a majority of the forest edge microclimatic gradients measured were influenced by edge effects. Yet this result also indicated that approximately one‐third of all air temperature and light intensity gradients and nearly one‐half of all vapor pressure deficit gradients recorded during this study were affected by factors independent of edge effects per se, and that forest edge microclimatic gradients were temporally nonconstant. For air temperature and vapor pressure deficit gradients, low spatial but high temporal variation existed in estimated edge width and the relative change in microclimate between the forest edge and interior. For light intensity gradients, both high spatial and temporal variability characterized estimated edge width and relative change in microclimate between the forest edge and interior. The pooled mean edge width and relative change in microclimate between die forest edge and interior across the four forest edge transects for air temperature, vapor pressure deficit, and light intensity gradients were 94.1 m and 2.00°C, 82.6 m and 0.29 kPa, and 60.5 m and 10.6 joules/sec/m2, respectively. These results suggest that forest edge microclimatic gradients in general may be inherently dynamic and nonconstant.