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1.
Trends Ecol Evol ; 39(4): 318-319, 2024 Apr.
Article in English | MEDLINE | ID: mdl-38461120

ABSTRACT

Previous studies demonstrated decreasing body size of birds in response to rising temperatures. Recently, Neate-Clegg et al. documented that birds have been becoming larger in an Afromontane forest over four decades. This highlights the complexity of morphological responses to climate, the importance of context, and the need to study phenomena in a diversity of regions.


Subject(s)
Climate Change , Forests , Animals , Birds , Body Size , Temperature
2.
New Phytol ; 242(1): 49-60, 2024 Apr.
Article in English | MEDLINE | ID: mdl-37984803

ABSTRACT

Tree stem methane emissions are important components of lowland forest methane budgets. The potential for species-specific behaviour among co-occurring lowland trees with contrasting bark characteristics has not been investigated. We compare bark-mediated methane transport in two common lowland species of contrasting bark characteristics (Melaleuca quinquenervia featuring spongy/layered bark with longitudinally continuous airspaces and Casuarina glauca featuring hard/dense common bark) through several manipulative experiments. First, the progressive cutting through M. quinquenervia bark layers caused exponential increases in methane fluxes (c. 3 orders of magnitude); however, sapwood-only fluxes were lower, suggesting that upward/axial methane transport occurs between bark layers. Second, concentrated methane pulse-injections into exposed M. quinquenervia bark, revealed rapid axial methane transport rates (1.42 mm s-1 ), which were further supported through laboratory-simulated experiments (1.41 mm s-1 ). Laboratory-simulated radial CH4 diffusion rates (through bark) were c. 20-times slower. Finally, girdling M. quinquenervia stems caused a near-instantaneous decrease in methane flux immediately above the cut. By contrast, girdling C. glauca displayed persistent, though diminished, methane fluxes. Overall, the experiments revealed evidence for rapid 'between-bark' methane transport independent from the transpiration stream in M. quinquenervia, which facilitates diffusive axial transport from the rhizosphere and/or sapwood sources. This contrasts with the slower, radial 'through-bark' diffusive-dominated gas transportation in C. glauca.


Subject(s)
Melaleuca , Trees , Methane , Plant Bark , Forests , Carbon Dioxide , Soil
3.
Zookeys ; 1157: 43-93, 2023.
Article in English | MEDLINE | ID: mdl-37398628

ABSTRACT

Amphibians of Sekayu lowland forest have been studied more than a decade, with discoveries of new records of species showing no sign of abating between the years 2003 to 2020, indicating the remarkably rich diversity of anurans in this forest. Despite ceaseless anthropogenic activities in this area, this study successfully recorded 52 species of amphibians from 32 genera in the lowland forest of Sekayu. The species composition consisted of a single species from the family Ichthyophiidae and 51 species of anurans of 31 genera and six families. The number of species recorded has steadily increased especially during more recent surveys from 2015 to 2020. This study augments the total number of amphibian species recorded from Hulu Terengganu by ten additional species, increasing the total to 70 species for the district.

4.
Trop Life Sci Res ; 33(2): 91-131, 2022 Jul.
Article in English | MEDLINE | ID: mdl-35966269

ABSTRACT

An inventory of herpetofauna species from western part of Nusa Kambangan Island, Central Java, Indonesia, is presented. There are 43 herpetofauna species reported (16 amphibians and 27 reptiles). This study confirmed new distribution record and list some of threatened species. In light of the imminent human disturbances on Nusa Kambangan Island, a conservation plan is urgently needed.

5.
Primates ; 63(1): 93-102, 2022 Jan.
Article in English | MEDLINE | ID: mdl-34853929

ABSTRACT

Plant exudates are an important food source for many primates. The Critically Endangered Javan slow loris (Nycticebus javanicus) was previously found to prefer Acacia decurrens exudate in an anthropogenically disturbed site, while its feeding habits in secondary natural forest remain unknown. Knowledge of the chemical characteristics of the plant exudates that Javan slow lorises consume is limited, especially with respect to those that they feed on in natural forests. As plant exudates may contain plant secondary metabolites (PSM), which are considered unpalatable in high concentrations, differences in PSM composition may drive feeding preferences. This research aims firstly to confirm exudate consumption by the Javan slow loris in a lowland tropical forest in Central Java, and secondly to identify the chemical characteristics of the exudates consumed. We followed wild slow lorises in Kemuning Forest, Central Java and observed their behaviour. We investigated the gum-producing trees that were utilized by the slow lorises by tapping the exudates and examining their nutritional and PSM contents. We found that exudates are the predominant food source for the Javan slow loris in this lowland forest, and that their nutritional contents are similar to those of exudates consumed by lorises in anthropogenically disturbed areas. Significant differences in polysaccharide and flavonoid contents were found between consumed and unconsumed exudates. Knowledge of the diet of the Javan slow loris is crucial to its conservation, and our findings confirm the importance of exudates in its diet. We also highlight the need to preserve natural slow loris habitat, and to manage the diets of these species in captivity. The results of this study indicate that plant exudates should constitute a significant portion of the diet of captive slow lorises, and that the presence of exudate-producing trees is vital in areas into which slow lorises are to be translocated.


Subject(s)
Lorisidae , Animals , Diet/veterinary , Ecosystem , Forests , Trees
6.
Rev. peru. biol. (Impr.) ; 28(spe): e21917, dic. 2021. tab, graf
Article in Spanish | LILACS-Express | LILACS | ID: biblio-1377183

ABSTRACT

Resumen En este trabajo presentamos una lista actualizada de los murciélagos de Loreto basada en la revisión de bases de datos, colecciones científicas y literatura especializada. Encontramos que Loreto es el departamento con mayor diversidad de murciélagos del Perú, con 114 especies agrupadas en 7 familias (19.9% de la mastofauna peruana), y que incluyen dos de las nueve especies endémicas para Perú: Micronycteris (Micronycteris) matses y Hsunycteris dashe. Además, se encontraron 444 localidades diferentes con registros de especímenes, principalmente ubicadas a lo largo de ríos. Las especies registradas en cuatro o menos localidades únicas fueron consideradas como raras, mientras que las especies registradas en 111 o más localidades únicas fueron consideradas comunes. Presentamos un mapa de las ecorregiones de Loreto con las localidades únicas, tanto históricas como contemporáneas, además de un mapa de densidad de localidades por cada 25 km2 donde se identifican 6 zonas de vacíos de información: 1) norte y centro de Putumayo 2) noroeste de Maynas y noreste de Loreto, 3) centro de Maynas, 4) centro-norte del Datem del Marañón, norte de Alto Amazonas y extremo occidental de Loreto, 5) centro-sur de Requena y extremo oriental de Ucayali y 6) extremo occidental de Ucayali. Finalmente presentamos mapas de distribución para cada especie aquí reportada para Loreto.


Abstract In this work, an updated list of species of bats from Loreto is presented, this was elaborated using information of databases, zoological collections, and specialized literature. The results confirm Loreto as the most diverse department of Peru with 114 species of bats grouped into 7 families (19.9% of the Peruvian mastofauna), which include two of the nine endemic species to Peru: Micronycteris (Micronycteris) matses and Hsunycteris dashe. Additionally, 444 different locations were found with specimen records, located mainly along rivers. Species recorded in four or less different locations are considered rare, while species recorded in 111 or more different locations are considered common. We present a map of the Loreto ecoregions with the different localities, both historical and contemporary, as well as a map of density of locations per 25 km2, which identifies 6 areas of information gaps: 1) North and middle Putumayo, 2) Northwest Maynas and northeast Loreto, 3) Middle Maynas, 4) North-middle Datem del Marañón, north Alto Amazonas and western end of Loreto, 5) South-middle Requena and eastern end of Ucayali and 6) Western end of Ucayali. Finally we present distribution maps for each species reported here for Loreto.

7.
Rev. peru. biol. (Impr.) ; 28(spe): e21910, dic. 2021. tab, graf
Article in Spanish | LILACS-Express | LILACS | ID: biblio-1377184

ABSTRACT

Resumen En el presente trabajo, presentamos una lista actualizada de mamíferos mayores para Loreto compuesta por 72 especies en 8 órdenes y 25 familias. Esta lista fue elaborada a partir de la minuciosa revisión de bases de datos, colecciones zoológicas y publicaciones científicas. En Loreto se encuentran 5 especies endémicas nacionales: Lagothrix flavicauda, Saguinus (Leontocebus) illigeri, Saguinus (Leontocebus) nigrifrons, Pithecia aequatorialis y Pithecia isabela, siendo las tres últimas también endémicas para Loreto. Se encontraron 292 localidades diferentes a partir de 3286 registros de mamíferos mayores. Se presenta un mapa de distribución de las localidades analizadas remarcando ecorregiones y registros históricos (antes del 2001) y contemporáneos (después del 2001). Asimismo, se presentan mapas con la distribución de las localidades donde han sido registradas las 72 especies estudiadas, y un mapa de densidad de las localidades registradas, el cual permite identificar dos zonas con vacíos de información: 1) la zona Datem del Marañón-Loreto y 2) la zona Alto Amazonas-Ucayali. Estas zonas requieren evaluaciones urgentes para complementar el conocimiento de la biodiversidad de Loreto y sustentar adecuadamente los planes de conservación y desarrollo sustentable.


Abstract In this work, we present an updated list of large mammals for Loreto composed of 72 species in 8 orders and 25 families. This list is elaborated from review of databases, zoological collections, and scientific publications. In Loreto is registered five Peruvian endemic species: Lagothrix flavicauda, Saguinus (Leontocebus) illigeri, Saguinus (Leontocebus) nigrifrons, Pithecia aequatorialis and Pithecia isabela; the last three have presence only in Loreto. We found 292 different locations and 3286 records of large mammals and build a distribution map highlighting ecoregions and historical (before 2001) and contemporary (after 2001) records. Likewise, we build maps for each of the 72 species with records in Loreto, and a density map that reveal two areas with information gaps: 1) the Datem del Marañón-Loreto zone, and 2) the Alto Amazonas-Ucayali zone. These zones require urgent evaluations to complement knowledge of Loreto's biodiversity and adequately support conservation and sustainable development plans.

8.
Glob Chang Biol ; 26(3): 1374-1389, 2020 03.
Article in English | MEDLINE | ID: mdl-31665558

ABSTRACT

The flux and composition of carbon (C) from land to rivers represents a critical component of the global C cycle as well as a powerful integrator of landscape-level processes. In the Congo Basin, an expansive network of streams and rivers transport and cycle terrigenous C sourced from the largest swathe of pristine tropical forest on Earth. Increasing rates of deforestation and conversion to agriculture in the Basin are altering the current regime of terrestrial-to-aquatic biogeochemical cycling of C. To investigate the role of deforestation on dissolved organic and inorganic C (DOC and DIC, respectively) biogeochemistry in the Congo Basin, six lowland streams that drain catchments of varying forest proportion (12%-77%) were sampled monthly for 1 year. Annual mean concentrations of DOC exhibited an asymptotic response to forest loss, while DIC concentrations increased continuously with forest loss. The isotopic signature of DIC became significantly more enriched with deforestation, indicating a shift in source and processes controlling DIC production. The composition of dissolved organic matter (DOM), as revealed by ultra-high-resolution mass spectrometry, indicated that deforested catchments export relatively more aliphatic and heteroatomic DOM sourced from microbial biomass in soils. The DOM compositional results imply that DOM from the deforested sites is more biolabile than DOM from the forest, consistent with the corresponding elevated stream CO2 concentrations. In short, forest loss results in significant and comprehensive shifts in the C biogeochemistry of the associated streams. It is apparent that land-use conversion has the potential to dramatically affect the C cycle in the Congo Basin by reducing the downstream flux of stable, vascular-plant derived DOC while increasing the transfer of biolabile soil C to the atmosphere.


Subject(s)
Carbon , Rivers , Agriculture , Congo , Forests
9.
Biodivers Data J ; 7: e46948, 2019.
Article in English | MEDLINE | ID: mdl-31885462

ABSTRACT

BACKGROUND: The Congo Basin rainforest is the second largest rainforest in the world and one of the most biodiverse regions on Earth. Nevertheless, the Congo Basin biodiversity remains to be fully mapped, with many species awaiting discovery or official description. In recent years, much effort has been put into research on shrews (Soricidae), particularly in the region around Kisangani (D.R. Congo). Shrews are opportunistic feeders that are able to forage on a large diversity of invertebrate prey and therefore play an important role in the forest ecosystem. Furthermore, as they largely depend on forest habitats and have limited dispersal capacities, shrews form an interesting model group to study biogeographic patterns in the Congo Basin. NEW INFORMATION: This paper collates the efforts on shrew research from the wider region around Kisangani, in the centre of the Congo Basin. Apart from sampling information, the dataset includes morphological measures, DNA sequences and photographs. This dataset is therefore critical in the study of the taxonomy and ecology of Soricidae in the Congo Basin lowland rainforests.

10.
PeerJ ; 6: e4241, 2018.
Article in English | MEDLINE | ID: mdl-29333349

ABSTRACT

Terrestrial mammals are important components of lowland forests in Amazonia (as seed dispersal agents, herbivores, predators) but there are relatively few detailed studies from areas that have not been affected by human activities (e.g., hunting, logging). Yet, such information is needed to evaluate effects of humans elsewhere. We used camera traps to sample medium to large-sized terrestrial mammals at a site in lowland forests of eastern Ecuador, one of the most biologically rich areas in the world. We deployed cameras on two study plots in terra firme forest at Tiputini Biodiversity Station. Sixteen cameras were arranged 200 m apart in a 4 × 4 grid on each plot. Cameras were operated for  60 days in January-March, 2014-2017, for a total of 3,707 and 3,482 trap-days on the two plots (Harpia, Puma). A total of 28 species were recorded; 26 on Harpia and 25 on Puma. Number of species recorded each year was slightly greater on Harpia whereas overall capture rates (images/100 trap-days) were higher on Puma. Although most species were recorded on each plot, differences in capture rates meant that yearly samples on a given plot were more similar to each other than to samples on the other plot. Images of most species showed a clumped distribution pattern on each plot; Panthera onca was the only species that did not show a clumped distribution on either plot. Images at a given camera location showed no evidence of autocorrelation with numbers of images at nearby camera locations, suggesting that species were responding to small-scale differences in habitat conditions. A redundancy analysis showed that environmental features within 50 or 100 m of camera locations (e.g., elevation, variation in elevation, slope, distance to streams) accounted for significant amounts of variation in distribution patterns of species. Composition and relative importance based on capture rates were very similar to results from cameras located along trails at the same site; similarities decreased at increasing spatial scales based on comparisons with results from other sites in Ecuador and Peru.

11.
Zookeys ; (715): 103-159, 2017.
Article in English | MEDLINE | ID: mdl-29302235

ABSTRACT

The Brazilian mountain ranges from the Guiana Shield highlands are largely unexplored, with an understudied herpetofauna. Here the amphibian and reptile species diversity of the remote Serra da Mocidade mountain range, located in extreme northern Brazil, is reported upon, and biogeographical affinities and taxonomic highlights are discussed. A 22-days expedition to this mountain range was undertaken during which specimens were sampled at four distinct altitudinal levels (600, 960, 1,060 and 1,365 m above sea level) using six complementary methods. Specimens were identified through an integrated approach that considered morphological, bioacoustical, and molecular analyses. Fifty-one species (23 amphibians and 28 reptiles) were found, a comparable richness to other mountain ranges in the region. The recorded assemblage showed a mixed compositional influence from assemblages typical of other mountain ranges and lowland forest habitats in the region. Most of the taxa occupying the Serra da Mocidade mountain range are typical of the Guiana Shield or widely distributed in the Amazon. Extensions of known distribution ranges and candidate undescribed taxa are also recorded. This is the first herpetofaunal expedition that accessed the higher altitudinal levels of this mountain range, contributing to the basic knowledge of these groups in remote areas.

12.
Mol Phylogenet Evol ; 88: 64-74, 2015 Jul.
Article in English | MEDLINE | ID: mdl-25800284

ABSTRACT

The lowland forests of western and central tropical Africa are separated by several potential biogeographic barriers to dispersal for forest adapted vertebrates. The two primary barriers are (1) the Dahomey Gap, a savanna corridor that reaches the coast of southern Ghana, Togo and Benin, and separates the West African rainforest into the Upper (Ghana west to Guinea) and Lower Guinea (Nigeria to Uganda and Angola) forest blocks, and (2) the Lower Niger River, a large delta that separates Western and Eastern Nigeria. Previous studies on terrestrial vertebrates (lizards, mammals and birds) have highlighted a genetic break in the Dahomey Gap/Lower Niger River area although the relative importance of each barrier has not been assessed due to limitations in geographic sampling. We compared the phylogeographic history of two co-distributed sister-species of woodpeckers (Campethera caroli and C. nivosa) using data from three loci representing all inheritance modes. Our analyses revealed that both the Dahomey Gap and possibly the Lower Niger River acted as strong biogeographic barriers for the two woodpecker species, with the Lower Niger River being the first barrier to have formed, leading to three distinct populations of C. nivosa. Our divergence time analyses revealed that both these biogeographic barriers formed during the Pleistocene, supporting the Pleistocene refuge hypothesis, with the Dahomey Gap likely appearing about 0.5 myr BP. No genetic structure was recovered among sampled populations in either the Upper or the Lower Guinea Forest Block for both species, despite the considerable geographic area covered.


Subject(s)
Birds/classification , Phylogeny , Africa, Western , Animal Migration , Animals , Birds/genetics , Genetic Variation , Phylogeography
13.
Bioscience ; 65(9): 906-921, 2015 Sep 01.
Article in English | MEDLINE | ID: mdl-26955086

ABSTRACT

The temperature sensitivity of soil organic matter (SOM) decomposition in tropical forests will influence future climate. Studies of a 3.5-kilometer elevation gradient in the Peruvian Andes, including short-term translocation experiments and the examination of the long-term adaptation of biota to local thermal and edaphic conditions, have revealed several factors that may regulate this sensitivity. Collectively this work suggests that, in the absence of a moisture constraint, the temperature sensitivity of decomposition is regulated by the chemical composition of plant debris (litter) and both the physical and chemical composition of preexisting SOM: higher temperature sensitivities are found in litter or SOM that is more chemically complex and in SOM that is less occluded within aggregates. In addition, the temperature sensitivity of SOM in tropical montane forests may be larger than previously recognized because of the presence of "cold-adapted" and nitrogen-limited microbial decomposers and the possible future alterations in plant and microbial communities associated with warming. Studies along elevation transects, such as those reviewed here, can reveal factors that will regulate the temperature sensitivity of SOM. They can also complement and guide in situ soil-warming experiments, which will be needed to understand how this vulnerability to temperature may be mediated by altered plant productivity under future climatic change.

14.
Ecol Evol ; 4(18): 3675-88, 2014 Sep.
Article in English | MEDLINE | ID: mdl-25478157

ABSTRACT

A life-history trade-off between low mortality in the dark and rapid growth in the light is one of the most widely accepted mechanisms underlying plant ecological strategies in tropical forests. Differences in plant functional traits are thought to underlie these distinct ecological strategies; however, very few studies have shown relationships between functional traits and demographic rates within a functional group. We present 8 years of growth and mortality data from saplings of 15 species of Dipterocarpaceae planted into logged-over forest in Malaysian Borneo, and the relationships between these demographic rates and four key functional traits: wood density, specific leaf area (SLA), seed mass, and leaf C:N ratio. Species-specific differences in growth rates were separated from seedling size effects by fitting nonlinear mixed-effects models, to repeated measurements taken on individuals at multiple time points. Mortality data were analyzed using binary logistic regressions in a mixed-effects models framework. Growth increased and mortality decreased with increasing light availability. Species differed in both their growth and mortality rates, yet there was little evidence for a statistical interaction between species and light for either response. There was a positive relationship between growth rate and the predicted probability of mortality regardless of light environment, suggesting that this relationship may be driven by a general trade-off between traits that maximize growth and traits that minimize mortality, rather than through differential species responses to light. Our results indicate that wood density is an important trait that indicates both the ability of species to grow and resistance to mortality, but no other trait was correlated with either growth or mortality. Therefore, the growth mortality trade-off among species of dipterocarp appears to be general in being independent of species crossovers in performance in different light environments.

15.
Rev. biol. trop ; 62(2): 689-698, Jun.-Aug. 2014. ilus, tab
Article in English | LILACS | ID: lil-715463

ABSTRACT

Jaguars (Panthera onca) are the largest predator in lowland forests of Amazonia but there have been few studies on their occurrence and activity in such forests. Here, we used camera traps to document the occurrence and activity of jaguars within a local area (~650ha) of lowland forest of Eastern Ecuador, over two sample periods (2005-2008, 7 222 trap days; 2010-2012, 6 199 trap days). We accumulated 151 independent photos of jaguars (189 total photographs) that represented 21 different individuals, including 11 males (114 photographs), seven females (32 photographs), and three that could not be assigned to a sex. Individual jaguars varied in the number of months they were recorded in the area; ten were photographed in only one month; five were photographed over periods of 8 to 22 months; and five from 45 to 81 months. Capture rates across all camera stations averaged 10.6/1 000 trap days; capture rates did not differ between the two sample periods. Male jaguars were more active during the day (06:00am-18:00pm; 71% of photographs), whereas females were equally active during the day and night. Monthly activity was variable but showed no consistent pattern. Although the study area is much smaller than typical home ranges of jaguars, the area is clearly visited by a large number of different individuals, some of whom repeatedly visit the area, indicating that it forms part of their home range. Other individuals likely were simply passing through the area. Based on the number of jaguars recorded during this study, it is clear that the region is an important area for conservation. Continued protection will be needed to ensure that populations of jaguars and other species remain viable. Rev. Biol. Trop. 62 (2): 689-698. Epub 2014 June 01.


El jaguar (Panthera onca) es el depredador más grande de los bosques bajos de la Amazonía, pero existen pocos estudios sobre su presencia y actividad en los mismos. En este estudio utilizamos cámaras trampa para documentar la presencia y actividad de jaguares dentro de una área de bosque bajo de la Amazonía este de Ecuador (~650 ha) en dos períodos (2005-2008, 7 222 trampas noche; 2010-2012, 6 199 trampas noche). Acumulamos 151 fotos independientes de jaguares (189 fotografías en total) que representaron 21 individuos, incluyendo 11 machos (114 fotos), siete hembras (32 fotos) y tres a los que no se les pudo asignar sexo. Los jaguares individuales variaron en el número de meses en que fueron registrados en el área; diez fueron fotografiados solo en un mes; cinco fueron fotografiados en un periodo entre 8 y 22 meses; y cinco jaguares entre 45 y 81. Las tasas de captura a través de las estaciones de trampeo promediaron 10.6/1 000 trampas noche; las tasas de captura no presentaron diferencias en los dos períodos de muestreo. Los jaguares machos fueron más activos durante el día (06:00am-18:00pm; 71% de las fotografías) mientras que las hembras fueron igualmente activas tanto en el día como en la noche. La actividad mensual fue variable pero no mostró un patrón consistente. Aunque el área de estudio es mucho más pequeña que el rango de vida típico para un jaguar, el área es claramente visitada por un alto número de individuos diferentes, algunos de los cuales visitan repetidamente el lugar, indicando que este forma parte de su rango de vida. Es probable que otros individuos solamente sean transeúntes del área.


Subject(s)
Animals , Female , Male , Behavior, Animal/physiology , Panthera/physiology , Ecuador , Photography , Population Density , Panthera/classification , Trees
16.
Interciencia ; 34(4): 232-239, abr. 2009. ilus, tab
Article in English | LILACS | ID: lil-630813

ABSTRACT

The present study describes and evaluates the horizontal and vertical structures of a lowland forest fragment on a hillock in the municipality of Silva Jardim, Rio de Janeiro State, Brazil (22º31’56’’S and 42º20’46’’W). Twenty plots (10´2m) totaling 0.5ha were laid out following the slope grade using DBH³5cm as the inclusion criterion. A total of 734 individuals were encountered, yielding a total density of 1468 ind./ha and a total basal area of 10783m². The richness values (129 species/41 families), Shannon-Wiener diversity (4.22) and equitability (0.87) indices indicated an accentuated floristic heterogeneity and low ecological dominance. Lauraceae, Myrtaceae, Fabaceae and Euphorbiaceae showed the greatest species richness, corroborating other studies that indicated these species as the most representative of Atlantic Forest areas in southeastern Brazil. The species with the greatest importance values (VI) were Aparisthmium cordatum, Guapira opposita, Lacistema pubescens, Xylopia sericea, Tapirira guianensis and Piptocarpha macropoda. The high diversity observed was influenced by earlier anthropogenic actions and by the current successional stage. The forest fragment studied demonstrated closer floristic similarity to areas inventoried in a close-by biological reserve than to fragments dispersed throughout the coastal plain. Similarities in soil type, degree of soil saturation and use-history of forest resources all support these relationships. The fragmented physiognomy of the central lowland in this region and the use-history of the landscape make these small remnant forest areas important in terms of establishing strategies for landscape restoration and species conservation.


Este estudio tuvo como objetivo describir y evaluar las estructuras horizontal y vertical de bosques de tierras bajas en pequeñas colinas (22º31'56''S y 42º20'46''O) en el municipio de Silva Jardim, Río de Janeiro, Brasil. Fueron asignadas, a lo largo de la pendiente, 20 parcelas (10´25m) totalizando 0,5ha, con criterio de inclusión de DAP³5cm. Se registraron 734 individuos, con una densidad total de 1468 ind/ha y 10783m² de área basal total. Los valores de riqueza (129 especies/41 familias), diversidad de Shannon-Wiener (4,22) y homogeneidad (0,87) indican una acentuada heterogeneidad florística y baja dominancia ecológica. Lauraceae, Myrtaceae, Fabaceae y Euphorbiaceae presentan la mayor riqueza, corroborando estudios que las muestran como las más representativas en la composición florística de la Selva Atlántica del sudeste de Brasil. Las especies de mayor valor de importancia (VI) fueron Aparisthmium cordatum, Guapira opposita, Lacistema pubescens, Xylopia sericea, Tapirira guianensis y Piptocarpha macropoda. La elevada diversidad encontrada es justificada por la acción antrópica anterior y el actual estado sucesional. El fragmento estudiado presenta mayor similitud florística con áreas inventariadas en una reserva biológica cercana que con los fragmentos dispersos por la región llana costera. Semejanzas de tipo de suelo, saturación hídrica e histórico de uso de los recursos forestales soportan esta similitud. La condición de fragmentación que caracteriza la región de planicie costera central del estado de Río de Janeiro y el aumento de datos disponibles hacen de estos pequeños remanentes forestales áreas de marcada relevancia para el establecimiento de estrategias de restauración del paisaje y conservación de especies.


Neste estudo objetivou-se descrever e avaliar as estruturas horizontal e vertical de floresta de baixada sobre morrote mamelonar (22º31'56''S e 42º20'46''O) no município de Silva Jardim, RJ. Para tanto, alocou-se ao longo do eixo de aclive, 20 parcelas (10´25m), totalizando 0,5ha, com critério de inclusão DAP³5cm. Registrou-se 734 indivíduos, perfazendo densidade total por área de 1468 ind/ha e 10783m2 de área basal total. Os valores de riqueza (129 espécies/41 famílias), diversidade de Shannon (4,22) e de eqüitabilidade (0,87) indicam acentuada heterogeneidade florística e baixa dominância ecológica. Lauraceae, Myrtaceae, Fabaceae e Euphorbiaceae apresentaram as maiores riquezas, corroborando outros estudos que as indicam como as mais representativas na composição florística da Floresta Atlântica do Sudeste do Brasil. As espécies de maior importância (VI) foram Aparisthmium cordatum, Guapira opposita, Lacistema pubescens, Xylopia sericea, Tapirira guianensis e Piptocarpha macropoda. A elevada diversidade encontrada se justifica pelas ações antrópicas pretéritas e pelo atual estágio sucessional. O fragmento estudado apresenta maior similaridade florística às áreas inventariadas no Rebio do que aos fragmentos dispersos pela região da planície. As semelhanças do tipo de solo, grau de saturação hídrica e histórico de uso dos recursos florestais suportam esta similaridade. A condição de fragmentação que caracteriza a região da planície central costeira do Rio de Janeiro, acrescida dos dados disponíveis desta paisagem, tornam estes pequenos remanescentes florestais como áreas de relevância para o estabelecimento de estratégias de restauração da paisagem e conservação de espécies.

17.
Rev. biol. trop ; 54(2): 357-361, jun. 2006. tab
Article in English | LILACS | ID: lil-492063

ABSTRACT

The nitrogen and phosphorus supply in a lowland rain forest with a nutrient-rich soil was investigated by means of the leaf N/P quotient. It was hypothesised a high N and P supply to the forest ecosystem with a N and P rich soil. Total N and extractable P were determined in the surface (10 cm) soil of three plots of the forest. Total N was analysed by the Kjeldahl method, and P was extracted with HCI and NH4F. The leaf N/P quotient was evaluated from the senesced leaves of 11 dominant tree species from the mature forest. Samples of 5 g of freshly fallen leaves were collected from three trees of each species. Nitrogen was analysed by microkjeldahl digestion with sulphuric acid and distilled with boric acid, and phosphorus was analysed by digestion with nitric acid and perchloric acid, and determined by photometry. Concentrations of total N (0.50%, n = 30) and extractable P (4.11 microg g(-1), n = 30) in the soil were high. As expected, P supply was sufficient, but contrary to expected, N supply was low (N/P = 11.8, n = 11).


A través del cociente foliar N/P, se investigó la disponibilidad de nitrógeno y fósforo en una selva húmeda tropical con suelo fértil. Como hipótesis se esperaba encontrar una alta disponibilidad de N y P en el ecosistema debido a un suelo rico en N y P. Se determinó el N total y el P extraible en el suelo superficial (10 cm) en tres sitios de la selva. El N total se analizó por el método Kjeldahl y el P por extracción con HCl y NH4F. El cociente foliar N/P se evaluó a partir de hojas seniles de 11 especies arbóreas dominantes de la selva madura. Se recolectaron muestras de 5 g de hojas recién caídas de tres árboles de cada especie. El nitrógeno se analizó por digestión microkjeldahl con ácido sulfúrico y destilación con ácido bórico, y el fósforo por digestión con ácido nítrico y ácido perclórico, y determinación con fotometría. Las concetraciones de N total (0.50%, n = 30) y P extraible (4.11 [mi]g g-1, n = 30) en el suelo fueron altas. Tal como se esperaba, la disponibilidad de P fue suficiente, pero contrariamente a lo esperado, la disponibilidad de N fue baja (N/P = 11.8, n = 11).


Subject(s)
Ecosystem , Plant Leaves/chemistry , Phosphorus/analysis , Nitrogen/analysis , Soil/analysis , Trees/physiology , Rain , Tropical Climate , Mexico
18.
Oecologia ; 84(3): 326-339, 1990 Oct.
Article in English | MEDLINE | ID: mdl-28313022

ABSTRACT

The results of an analysis of gorilla diet in the Lopé Reserve, Gabon are presented. Samples were assayed for nutrients and plant secondary compounds (total phenols, condensed tannins and alkaloids) in an attempt to explain gorilla food choice. The diet is the most diverse so far analysed for gorillas; it seems to be a balance between sugary fruit, proteinaceous leaves, and relatively fibrous stems. Most fruits and herbaceous stems are succulent, but some drier, fibrous fruit and bark is also consumed. Seeds are another component of the diet, including unripe ones. Fruit, seeds, leaves and bark may all contain very high levels of total phenols and condensed tannins; but all herbaceous stems assayed contain low levels of these compounds. Alkaloids are not apparently a significant component of gorilla foods, and may be avoided. Gorillas at Lopé tend to avoid fatty fruit, and select leaves which are high in protein and low in fibre compared to the general vegetation. When fruit and preferred young leaves are scarce, proteinaceous barks and mature leaves, and sugary pith, are important sources of nutrients. We conclude that gorillas exploit the broad frugivore niche in West African lowland forests, and are part of the frugivore community there. What distinguishes them is their ability to eat large fibrous fruit, mature leaves and stems, and to overcome high levels of phenolics (we use "phenolics" as an umbrella term for both total phenols and condensed tannins). Gorilla diet at Lopé overlaps greatly with that of sympatric, frugivorous, primates, and resembles more closely that of chimpanzees than it does gorilla diet studied elsewhere in Africa.

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