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Sample records for rain forest remnants

  1. 5 Floristics and structure of a Mixed Rain Forest remnant on the Catarinense Plateau

    Directory of Open Access Journals (Sweden)

    Carine Klauberg

    2010-03-01

    Full Text Available The objective of this study was to describe the floristics and the structure of tree species in the Parque Municipal Natural of Lages, SC, a remnant of mixed rain forest located in southern Brazil. For this, we allocated four plots (40 x 40m and each plot was divided into 16 sub-plots of 10 x 10m. Trees with dbh ≥ 5cm and height ≥ 1.3m were mapped, tagged and measured. The individuals were identified and voucher material was deposited in the herbarium. A total of 46 species were sampled, distributed in 39 genera and 27 families. The richest families in number of species were Myrtaceae, Lauraceae, Salicaceae and Sapindaceae. Seven species represented more than 60% of the total of individuals. The specific diversity was H’ = 3.05 nats.ind-1 (J’ = 0.81. The similarity among plots was 32 at 44%, indicating low similarity among plots. The spatial distribution of most of the species is classified as clumped, according to the Morisita index. This forest remains with a considerable richness and diversity with some endangered tree species such as Araucaria angustifolia and Dicksonia sellowiana. Due to its ecological importance for the local flora and fauna and the fragmentation process in the region, this remnant should be considered as a priority area for conservation.

  2. The pristine rain forest? Remnants of historical human impacts on current tree species composition and diversity

    NARCIS (Netherlands)

    Gemerden, van B.S.; Olff, H.; Parren, M.P.E.; Bongers, F.J.J.M.

    2003-01-01

    Aim Tropical rain forests are often regarded as pristine and undisturbed by humans. In Central Africa, community-wide disturbances by natural causes are rare and therefore current theory predicts that natural gap phase dynamics structure tree species composition and diversity. However, the dominant

  3. The pristine rain forest? Remnants of historical human impacts on current tree species composition and diversity

    NARCIS (Netherlands)

    Gemerden, Barend S. van; Olff, Han; Parren, Marc P.E.; Bongers, Frans

    2003-01-01

    Aim: Tropical rain forests are often regarded as pristine and undisturbed by humans. In Central Africa, community-wide disturbances by natural causes are rare and therefore current theory predicts that natural gap phase dynamics structure tree species composition and diversity. However, the dominant

  4. Influence of Atlantic Rain Forest remnants on the biological control of Euselasia apisaon (Dahman) (Lepidoptera: Riodinidae) by Trichogramma maxacalii (Voegele and Pointel) (Hymenoptera: Trichogrammatidae)

    International Nuclear Information System (INIS)

    Murta, Aline F.; Ker, Fabricio T.O.; Costa, Dalbert B.; Espirito-Santo, Mario M.; Faria, Mauricio L.

    2008-01-01

    This study evaluated the effects of Atlantic Rain Forest remnants on the natural biological control of Euselasia apisaon (Dahman) by the parasitoid Trichogramma maxacalii (Voegele and Pointel) in Eucalyptus plantations. The number of E. apisaon eggs/leaf was higher in the center than in the edge of the plantations (23.5 ± 7.61 vs. 14.8 ± 3.14), but parasitism showed the reversed pattern (72.4% in the center and 80.5% in the edge). The results indicated that natural regulation exerted by T. maxacalii on populations of E. apisaon may be enhanced by the preservation of fragments of native vegetation surrounding Eucalyptus plantations. (author)

  5. Rain Forest Murals

    Science.gov (United States)

    Kleiner, Cheryl

    2010-01-01

    The rain forest murals in the author's school began as a request from her principal to have students decorate the cafeteria with their own paintings. She decided to brainstorm ideas with her eighth-grade students. Taking into consideration the architectural space and the environmental concerns they wanted to convey, students chose the rain forest…

  6. Influence of Atlantic Rain Forest remnants on the biological control of Euselasia apisaon (Dahman) (Lepidoptera: Riodinidae) by Trichogramma maxacalii (Voegele and Pointel) (Hymenoptera: Trichogrammatidae); Efeitos de remanescentes de Mata Atlantica no controle biologico de Euselasia apisaon (Dahman) (Lepidoptera: Riodinidae) por Trichogramma maxacalii (Voegele e Pointel) (Hymenoptera: Trichogrammatidae)

    Energy Technology Data Exchange (ETDEWEB)

    Murta, Aline F.; Ker, Fabricio T.O.; Costa, Dalbert B. [Centro Universitario do Leste de Minas Gerais (UnilesteMG), Coronel Fabriciano, MG (Brazil). Lab. de Controle Biologico de Pragas; Espirito-Santo, Mario M.; Faria, Mauricio L. [Universidade Estadual de Montes Claros, MG (Brazil). Centro de Ciencias Biologicas e da Saude. Dept. de Biologia Geral

    2008-03-15

    This study evaluated the effects of Atlantic Rain Forest remnants on the natural biological control of Euselasia apisaon (Dahman) by the parasitoid Trichogramma maxacalii (Voegele and Pointel) in Eucalyptus plantations. The number of E. apisaon eggs/leaf was higher in the center than in the edge of the plantations (23.5 {+-} 7.61 vs. 14.8 {+-} 3.14), but parasitism showed the reversed pattern (72.4% in the center and 80.5% in the edge). The results indicated that natural regulation exerted by T. maxacalii on populations of E. apisaon may be enhanced by the preservation of fragments of native vegetation surrounding Eucalyptus plantations. (author)

  7. Rain Forests: Do They Hold Up the Sky?

    Science.gov (United States)

    Shaw, Donna Gail; Dybdahl, Claudia S.

    1992-01-01

    This paper uses the topic of rain forests to demonstrate how a meaningful and relevant Science, Technology, and Society program can be designed for intermediate-level students. Students create and immerse themselves in a tropical rain forest, explore the forest ecosystem and peoples, and consider solutions to the problem of deforestation. (JDD)

  8. Nucleated regeneration of semiarid sclerophyllous forests close to remnant vegetation

    NARCIS (Netherlands)

    Fuentes-Castillo, T.; Miranda, A.; Rivera-Hutinel, A.; Smith-Ramirez, C.; Holmgren, M.

    2012-01-01

    Natural regeneration of mediterranean plant communities has proved difficult in all continents. In this paper we assess whether regeneration of sclerophyllous forests shows nucleated patterns indicative of a positive effect of vegetation remnants at the landscape level and compare the regeneration

  9. Monitoring of rain water storage in forests with satellite radar

    OpenAIRE

    de Jong, JJM; Klaassen, W; Kuiper, PJC

    2002-01-01

    The sensitivity of radar backscatter to the amount of intercepted rain in temperate deciduous forests is analyzed to determine the feasibility of retrieval of this parameter from satellite radar data. A backscatter model is validated with X-band radar measurements of a single tree exposed to rain. A good agreement between simulation and measurements is observed and this demonstrates the ability of radar to measure the amount of intercepted rain. The backscatter model is next applied to simula...

  10. Pervasive Defaunation of Forest Remnants in a Tropical Biodiversity Hotspot

    Science.gov (United States)

    Canale, Gustavo R.; Peres, Carlos A.; Guidorizzi, Carlos E.; Gatto, Cassiano A. Ferreira; Kierulff, Maria Cecília M.

    2012-01-01

    Tropical deforestation and forest fragmentation are among the most important biodiversity conservation issues worldwide, yet local extinctions of millions of animal and plant populations stranded in unprotected forest remnants remain poorly explained. Here, we report unprecedented rates of local extinctions of medium to large-bodied mammals in one of the world's most important tropical biodiversity hotspots. We scrutinized 8,846 person-years of local knowledge to derive patch occupancy data for 18 mammal species within 196 forest patches across a 252,669-km2 study region of the Brazilian Atlantic Forest. We uncovered a staggering rate of local extinctions in the mammal fauna, with only 767 from a possible 3,528 populations still persisting. On average, forest patches retained 3.9 out of 18 potential species occupancies, and geographic ranges had contracted to 0–14.4% of their former distributions, including five large-bodied species that had been extirpated at a regional scale. Forest fragments were highly accessible to hunters and exposed to edge effects and fires, thereby severely diminishing the predictive power of species-area relationships, with the power model explaining only ∼9% of the variation in species richness per patch. Hence, conventional species-area curves provided over-optimistic estimates of species persistence in that most forest fragments had lost species at a much faster rate than predicted by habitat loss alone. PMID:22905103

  11. Pervasive defaunation of forest remnants in a tropical biodiversity hotspot.

    Directory of Open Access Journals (Sweden)

    Gustavo R Canale

    Full Text Available Tropical deforestation and forest fragmentation are among the most important biodiversity conservation issues worldwide, yet local extinctions of millions of animal and plant populations stranded in unprotected forest remnants remain poorly explained. Here, we report unprecedented rates of local extinctions of medium to large-bodied mammals in one of the world's most important tropical biodiversity hotspots. We scrutinized 8,846 person-years of local knowledge to derive patch occupancy data for 18 mammal species within 196 forest patches across a 252,669-km(2 study region of the Brazilian Atlantic Forest. We uncovered a staggering rate of local extinctions in the mammal fauna, with only 767 from a possible 3,528 populations still persisting. On average, forest patches retained 3.9 out of 18 potential species occupancies, and geographic ranges had contracted to 0-14.4% of their former distributions, including five large-bodied species that had been extirpated at a regional scale. Forest fragments were highly accessible to hunters and exposed to edge effects and fires, thereby severely diminishing the predictive power of species-area relationships, with the power model explaining only ~9% of the variation in species richness per patch. Hence, conventional species-area curves provided over-optimistic estimates of species persistence in that most forest fragments had lost species at a much faster rate than predicted by habitat loss alone.

  12. Remnant trees affect species composition but not structure of tropical second-growth forest.

    Science.gov (United States)

    Sandor, Manette E; Chazdon, Robin L

    2014-01-01

    Remnant trees, spared from cutting when tropical forests are cleared for agriculture or grazing, act as nuclei of forest regeneration following field abandonment. Previous studies on remnant trees were primarily conducted in active pasture or old fields abandoned in the previous 2-3 years, and focused on structure and species richness of regenerating forest, but not species composition. Our study is among the first to investigate the effects of remnant trees on neighborhood forest structure, biodiversity, and species composition 20 years post-abandonment. We compared the woody vegetation around individual remnant trees to nearby plots without remnant trees in the same second-growth forests ("control plots"). Forest structure beneath remnant trees did not differ significantly from control plots. Species richness and species diversity were significantly higher around remnant trees. The species composition around remnant trees differed significantly from control plots and more closely resembled the species composition of nearby old-growth forest. The proportion of old-growth specialists and generalists around remnant trees was significantly greater than in control plots. Although previous studies show that remnant trees may initially accelerate secondary forest growth, we found no evidence that they locally affect stem density, basal area, and seedling density at later stages of regrowth. Remnant trees do, however, have a clear effect on the species diversity, composition, and ecological groups of the surrounding woody vegetation, even after 20 years of forest regeneration. To accelerate the return of diversity and old-growth forest species into regrowing forest on abandoned land, landowners should be encouraged to retain remnant trees in agricultural or pastoral fields.

  13. Rain forest provides pollinating beetles for atemoya crops.

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    Blanche, Rosalind; Cunningham, Saul A

    2005-08-01

    Small beetles, usually species of Nitidulidae, are the natural pollinators of atemoya (Annona squamosa L. x A. cherimola Mill. hybrids; custard apple) flowers but commercial atemoya growers often need to carry out labor-intensive hand pollination to produce enough high-quality fruit. Because Australian rain forest has plant species in the same family as atemoya (Annonaceae) and because many rain forest plants are beetle pollinated, we set out to discover whether tropical rain forest in far north Queensland harbors beetles that could provide this ecosystem service for atemoya crops. Orchards were chosen along a gradient of increasing distance from tropical rain forest (0.1-24 km). We sampled 100 flowers from each of nine atemoya orchards and determined the identity and abundance of insects within each flower. To assess the amount of pollination due to insects, we bagged six flowers per tree and left another six flowers per tree accessible to insects on 10 trees at an orchard near rain forest. Results indicated that atemoya orchards pollinators that are likely to originate in tropical rain forest. These native beetles occurred reliably enough in crops near rain forest to have a positive effect on the quantity of fruit produced but their contribution was not great enough to satisfy commercial production needs. Management changes, aimed at increasing native beetle abundance in crops, are required before these beetles could eliminate the need for growers to hand pollinate atemoya flowers. Appreciation of the value of this resource is necessary if we are to develop landscapes that both conserve native biodiversity and support agricultural production.

  14. Plant diversity after rain-forest fires in Borneo

    NARCIS (Netherlands)

    Eichhorn, Karl August Otto

    2006-01-01

    In the last two decades El-Niño-induced fires have caused widespread destruction of forests in East Kalimantan. The 1997-98 fires were the most extensive yet. The post-fire situation was studied in detail by field assessments and high-resolution SAR-images. My results show that rain forests are

  15. Growth and yield model application in tropical rain forest management

    Science.gov (United States)

    James Atta-Boateng; John W., Jr. Moser

    2000-01-01

    Analytical tools are needed to evaluate the impact of management policies on the sustainable use of rain forest. Optimal decisions concerning the level of management inputs require accurate predictions of output at all relevant input levels. Using growth data from 40 l-hectare permanent plots obtained from the semi-deciduous forest of Ghana, a system of 77 differential...

  16. Fungus-Growing Termites Originated in African Rain Forest

    DEFF Research Database (Denmark)

    Aanen, Duur Kornelis; Eggleton, Paul

    2005-01-01

    are consumed (cf. [ [1] and [2] ]). Fungus-growing termites are found throughout the Old World tropics, in rain forests and savannas, but are ecologically dominant in savannas [ 3 ]. Here, we reconstruct the ancestral habitat and geographical origin of fungus-growing termites. We used a statistical model...... of habitat switching [ 4 ] repeated over all phylogenetic trees sampled in a Bayesian analysis of molecular data [ 5 ]. Our reconstructions provide strong evidence that termite agriculture originated in African rain forest and that the main radiation leading to the extant genera occurred there. Because...

  17. Histochemical Characterization of Rain-Forest Strain of Onchocerca ...

    African Journals Online (AJOL)

    Abstract: The histochemical characterization of rain-forest strain of Onchocerca volvulus isolated in Akamkpa of Cross River State, Nigeria was studied. In a preliminary survey of 350 persons from eight villages, 75(21.4%) were found to be positive for the parasite. Males (23.6%) were more infected than the females but there ...

  18. Disturbance, diversity and distributions in Central African rain forest

    NARCIS (Netherlands)

    Gemerden, van B.S.

    2004-01-01

    The aim of this study is to gain insight in the impact of human land use on plant community composition, diversity and levels of endemism in Central African rain forest. Human disturbance in this region is causing large-scale habitat degradation. The two most widespread forms of land use are

  19. Lessons Learnt on Rain Forest Management for Wood Production in ...

    African Journals Online (AJOL)

    The study was carried out with the aim of analyzing and establishing what lessons have been learnt from positive and negative experiences of various initiatives, projects and programmes aiming at sustainable management, use and conservation of rain forests in Sub-Saharan Africa. The lessons learnt from the case ...

  20. Tropical rain forest: a wider perspective

    National Research Council Canada - National Science Library

    Goldsmith, F. B

    1998-01-01

    .... Barbier -- Can non-market values save the tropical forests? / D. Pearce -- The role of policy and institutions / James Mayers and Stephen Bass -- Modelling tropical land use change and deforestation...

  1. Seasonal rhythms of seed rain and seedling emergence in two tropical rain forests in southern Brazil.

    Science.gov (United States)

    Marques, M C M; Oliveira, P E A M

    2008-09-01

    Seasonal tropical forests show rhythms in reproductive activities due to water stress during dry seasons. If both seed dispersal and seed germination occur in the best environmental conditions, mortality will be minimised and forest regeneration will occur. To evaluate whether non-seasonal forests also show rhythms, for 2 years we studied the seed rain and seedling emergence in two sandy coastal forests (flooded and unflooded) in southern Brazil. In each forest, one 100 x 30-m grid was marked and inside it 30 stations comprising two seed traps (0.5 x 0.5 m each) and one plot (2 x 2 m) were established for monthly monitoring of seed rain and a seedling emergence study, respectively. Despite differences in soil moisture and incident light on the understorey, flooded and unflooded forests had similar dispersal and germination patterns. Seed rain was seasonal and bimodal (peaks at the end of the wetter season and in the less wet season) and seedling emergence was seasonal and unimodal (peaking in the wetter season). Approximately 57% of the total species number had seedling emergence 4 or more months after dispersal. Therefore, both seed dormancy and the timing of seed dispersal drive the rhythm of seedling emergence in these forests. The peak in germination occurs in the wetter season, when soil fertility is higher and other phenological events also occur. The strong seasonality in these plant communities, even in this weakly seasonal climate, suggests that factors such as daylength, plant sensitivity to small changes in the environment (e.g. water and nutrient availability) or phylogenetic constraints cause seasonal rhythms in the plants.

  2. Nucleation procedures in the restoration of riverine areas of the Mixed Rain Forest, Southern Brazil

    Directory of Open Access Journals (Sweden)

    Ademir Reis

    2009-12-01

    Full Text Available Due to its significant importance in the history of the occupation of Southern Brazil, the mixed rain forest, particularly in the Planalto Norte Catarinense, was subjected to intense exploitation as well as the replacement of its original vegetation cover by pasture and agricultural areas. Nowadays, it suffers another great impact which is the homogeneous reforestation with species of Pinus. The present situation is characterized by the need for restoration of the local landscape’s connectivity, which means restoring degraded riverine areas by repairing the connectivity between original fragments and areas to be restored. This study investigated the role of the seed bank and seed rain of preserved adjacent riverine fragments and the efficiency of nucleation procedures in the restoration of degraded riverine areas in Pinus taeda L. producing farms. Samples of the seed bank and seed rain of preserved fragments were collected and techniques of soil transposition and artificial perches were applied in the open degraded areas. The riverine areas demonstrated the potential to initiate the secondary succession process, allowing the formation of initial succession stages. The use of nucleation procedures showed the possibility of accelerating the succession process and indicated the importance of establishing linkage points between open areas and conserved remnants.

  3. Explosive Radiation of Malpighiales Supports a Mid-Cretaceous Origin of Modern Tropical Rain Forests

    OpenAIRE

    Wurdack, Kenneth J.; Jaramillo, Carlos A.; Davis, Charles; Webb, Campbell O.; Donoghue, Michael J.

    2005-01-01

    Fossil data have been interpreted as indicating that Late Cretaceous tropical forests were open and dry adapted and that modern closed-canopy rain forest did not originate until after the Cretaceous-Tertiary (K/T) boundary. However, some mid-Cretaceous leaf floras have been interpreted as rain forest. Molecular divergence-time estimates within the clade Malpighiales, which constitute a large percentage of species in the shaded, shrub, and small tree layer in tropical rain forests worldwide, p...

  4. Damage-controlled logging in managed tropical rain forest in Suriname

    OpenAIRE

    Hendrison, J.

    1990-01-01

    Concern about worldwide deforestation and exploitation of the tropical rain forests has led to friction between national governments, wood industries and timber trade on the one hand, and scientists and environmental organizations on the other. One way to safeguard the tropical rain forests is to avoid human interference and to use forests only as nature reserves and as buffer zones of environmental protection. Some vulnerable tropical rain forests and those with unique flora and fau...

  5. Variação intraspecífica do lenho de Pseudopiptadenia contorta (DC. G.P. Lewis & M.P. Lima (Leguminosae - Mimosoideae de populações ocorrentes em dois remanescentes de Floresta Atlântica Intraspecific variation in wood anatomy of Pseudopiptadenia contorta (DC G.P. Lewis & M.P. Lima (Leguminosae -Mimosoidae in two Atlantic rain forest remnants

    Directory of Open Access Journals (Sweden)

    Maria Luiza R. da Costa Ribeiro

    2006-12-01

    Full Text Available O presente trabalho compara populações distintas de Pseudopiptadenia contorta (DC. G.P. Lewis & M.P. Lima ocorrentes em dois remanescentes de Floresta Atlântica no Estado do Rio de Janeiro. Foram amostradas árvores de diâmetro semelhante retas e sem defeitos aparentes. Os resultados obtidos comprovam estatisticamente a ocorrência de variação intraspecífica na estrutura anatômica da madeira. Os caracteres qualitativos mantiveram-se constantes, enquanto os quantitativos variaram, sendo os significativos, de acordo com o teste t de Student, a freqüencia, comprimento e diâmetro dos elementos vasos, o comprimento e espessura da parede das fibras, a freqüência e largura dos raios. A análise dos componentes principais, utilizando características anatômicas quantitativas ordenou as duas populações separadamente. O eixo I responde por 33% da variância total principalmente pela relação positiva do diâmetro do elemento de vaso, enquanto o eixo II responde por 20% da variância total, principalmente pelo comprimento das fibras.This study compares distinct populations of Pseudopiptadenia contorta (DC G.P. Lewis & M.P. Lima occurring in two remnants of Atlantic rain forest in Rio de Janeiro state. Trees with similar diameters and with no apparent defects were selected. The results confirm intraspecific variation in wood anatomy. Qualitative features do not change, while according to the Student t test quantitative features showed significant differences in vessel-element frequency, width, and length, fiber length and wall thickness, and ray frequency and width. Principal component analysis showed two separate populations. Factor 1 explains 33% of the total variance, mainly due to the positive relationship of vessel-element tangential diameter; factor 2 explains 20% of the total variance, mainly due to fiber length.

  6. Tropical rain-forest matrix quality affects bat assemblage structure in secondary forest patches

    NARCIS (Netherlands)

    Vleut, I.; Levy-Tacher, I.; Galindo-Gonzalez, J.; Boer, de W.F.; Ramirez-Marcial, N.

    2012-01-01

    We studied Phyllostomidae bat assemblage structure in patches of secondary forest dominated by the pioneer tree Ochroma pyramidale, largely (.85%) or partially (,35%) surrounded by a matrix of tropical rain forest, to test 3 hypotheses: the highest bat diversity and richness is observed in the

  7. Forest structure and carbon dynamics in Amazonian tropical rain forests.

    Science.gov (United States)

    Vieira, Simone; de Camargo, Plinio Barbosa; Selhorst, Diogo; da Silva, Roseana; Hutyra, Lucy; Chambers, Jeffrey Q; Brown, I Foster; Higuchi, Niro; dos Santos, Joaquim; Wofsy, Steven C; Trumbore, Susan E; Martinelli, Luiz Antonio

    2004-08-01

    Living trees constitute one of the major stocks of carbon in tropical forests. A better understanding of variations in the dynamics and structure of tropical forests is necessary for predicting the potential for these ecosystems to lose or store carbon, and for understanding how they recover from disturbance. Amazonian tropical forests occur over a vast area that encompasses differences in topography, climate, and geologic substrate. We observed large differences in forest structure, biomass, and tree growth rates in permanent plots situated in the eastern (near Santarém, Pará), central (near Manaus, Amazonas) and southwestern (near Rio Branco, Acre) Amazon, which differed in dry season length, as well as other factors. Forests at the two sites experiencing longer dry seasons, near Rio Branco and Santarém, had lower stem frequencies (460 and 466 ha(-1) respectively), less biodiversity (Shannon-Wiener diversity index), and smaller aboveground C stocks (140.6 and 122.1 Mg C ha(-1)) than the Manaus site (626 trees ha(-1), 180.1 Mg C ha(-1)), which had less seasonal variation in rainfall. The forests experiencing longer dry seasons also stored a greater proportion of the total biomass in trees with >50 cm diameter (41-45 vs 30% in Manaus). Rates of annual addition of C to living trees calculated from monthly dendrometer band measurements were 1.9 (Manaus), 2.8 (Santarém), and 2.6 (Rio Branco) Mg C ha(-1) year(-1). At all sites, trees in the 10-30 cm diameter class accounted for the highest proportion of annual growth (38, 55 and 56% in Manaus, Rio Branco and Santarém, respectively). Growth showed marked seasonality, with largest stem diameter increment in the wet season and smallest in the dry season, though this may be confounded by seasonal variation in wood water content. Year-to-year variations in C allocated to stem growth ranged from nearly zero in Rio Branco, to 0.8 Mg C ha(-1) year(-1) in Manaus (40% of annual mean) and 0.9 Mg C ha(-1) year(-1) (33% of

  8. BIOGEOGRAPHICAL IMPLICATIONS OF SOME PLANT SPECIES FROM A TROPICAL MONTANE RAIN FOREST IN SOUTHERN YUNNAN

    Institute of Scientific and Technical Information of China (English)

    ZHU Hua

    2004-01-01

    A pristine montane rain forest was recently discovered from Mengsong of Xishuangbanna in the southern Yunnan.It attracts botanists that many primitive plant taxa across various life forms were co-existed in the montane rain forest.In order to know the biogeography of the montane rain forest,distribution patterns of some species of biogeographical importance from the montane forest were enumerated and their biogeographical implications were discussed with geological explanation.It was concluded that the montane rain forest in the southern Yunnan has strong affinity to montane rain forests in Sumatra or Southeast Asia in broad sense.It was tentatively suggested that Sumatra could be once connected to Myanmar and drifted away due to northward movement of continental Asia by bumping of India plate.

  9. EXOTIC PLANTS IN THE CIBODAS BOTANIC GARDENS REMNANT FOREST: INVENTORY AND CLUSTER ANALYSIS OF SEVERAL ENVIRONMENTAL FACTORS

    Directory of Open Access Journals (Sweden)

    Decky Indrawan Junaedi

    2014-01-01

    Full Text Available Due to potential impact of invasive alien (exotic species to the natural ecosystems, inventory of exotic species in the Cibodas Botanic Gardens (CBG remnant forest area is an urgent need for CBG. Inventory of exotic species can assist gardens manager to set priorities and plan better responses for possible or existed invasive plants in the CBG remnants forest. The objectives of this study are to do inventory of the exotic species in the CBG remnant forest and to determine whether several environmental variables play role to the existence of exotic species in the CBG remnant forests. There are 26 exotic plant species (23 genera, 14 families found and recorded from all four remnant forests in CBG. Cluster analysis of four environmental variables shows that clustering of environmental factors of exotic species correlates with the abundances of those exotic species. The relation between environmental factor clusters and the abundance of those exotics signify the role of environmental variables on the existence of exotic plant species. The information of exotic plant species in the remnants forest is the base information for gardens manager to manage exotic species in CBG remnants forest. The relation of several environmental factors with exotic species abundance could assist gardens manager to understand better the supportive and or suppressor factors of exotics in the CBG remnants forest. Further study on these species is needed to set priorities to decide which species should be treated first in order to minimize the impact of exotic plant species to native ecosystem of CBG.

  10. EXOTIC PLANTS IN THE CIBODAS BOTANIC GARDENS REMNANT FOREST: INVENTORY AND CLUSTER ANALYSIS OF SEVERAL ENVIRONMENTAL FACTORS

    Directory of Open Access Journals (Sweden)

    Decky Indrawan Junaedi

    2014-01-01

    Full Text Available Due to potential impact of invasive alien (exotic species to the natural ecosystems, inventory of exotic species in the Cibodas Botanic Gardens (CBG remnant forest area is an urgent need for CBG. Inventory of exotic species can assist gardens manager to set priorities and plan better responses for possible or existed invasive plants in the CBG remnants forest. The objectives of this study are to do inventory of the exotic species in the CBG remnant forest and to determine whether several environmental variables play role to the existence of exotic species in the CBG remnant forests. There are 26 exotic plant species  (23 genera, 14 families found and recorded from all four remnant forests in CBG. Cluster analysis of four environmental variables shows that clustering of environmental factors of exotic species correlates with the abundances of those exotic species. The relation between environmental factor clusters and the abundance of those exotics signify the role of environmental variables on the existence of exotic plant species. The information of exotic plant species in the remnants forest is the base information for gardens manager to manage exotic species in CBG remnants forest. The relation of several environmental factors with exotic species abundance could assist gardens manager to understand better the supportive and or suppressor factors of exotics in the CBG remnants forest. Further study on these species is needed to set priorities to decide which species should be treated first in order to minimize the impact of exotic plant species to native ecosystem of CBG.

  11. Damage-controlled logging in managed tropical rain forest in Suriname

    NARCIS (Netherlands)

    Hendrison, J.

    1990-01-01

    Concern about worldwide deforestation and exploitation of the tropical rain forests has led to friction between national governments, wood industries and timber trade on the one hand, and scientists and environmental organizations on the other. One way to safeguard the tropical rain forests

  12. Regeneration in natural and logged tropical rain forest : modelling seed dispersal and regeneration

    NARCIS (Netherlands)

    Ulft, Lambertus Henricus van

    2004-01-01

    Regeneration and disturbance are thought to play key roles in the maintenance of the high tree species diversity in tropical rain forests. Nevertheless, the earliest stages in the regeneration of tropical rain forest trees, from seed production to established seedlings, have received little

  13. Genetic diversity in populations of Maytenus dasyclada (Celastraceae in forest reserves and unprotected Araucaria forest remnants

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    Manuel Castilhos Reichmann

    Full Text Available ABSTRACT Understanding the genetic structure and diversity of plants is fundamental to their conservation and permits their sustainable use by local communities. The genus Maytenus (Celastraceae is composed of plants possessing pharmacological and antioxidant properties. However, the genetic and economic properties of the species M. dasyclada, a typical species of Araucaria forests in Brazil and Uruguay, have been little studied. In this work, the genetic structure and diversity of natural populations of M. dasyclada located in unprotected and preserved forest remnants were investigated using RAPD and isozymes markers. The results demonstrated that in areas of preservation, populations of M. dasyclada possess a relatively high degree of polymorphism and high values for Na, Ne, Shannon index, He and Ho, indicating high genetic variability. Moreover, these protected populations are very close to each other and potentially experience significant gene flow. The results presented here highlight the relevance of preservation areas for the conservation of M. dasyclada, and that populations inhabiting these areas could serve as a genetic source for the recovery of populations in regions where genetic diversity has been lost.

  14. Agricultural intensification exacerbates spillover effects on soil biogeochemistry in adjacent forest remnants.

    Directory of Open Access Journals (Sweden)

    Raphael K Didham

    Full Text Available Land-use intensification is a central element in proposed strategies to address global food security. One rationale for accepting the negative consequences of land-use intensification for farmland biodiversity is that it could 'spare' further expansion of agriculture into remaining natural habitats. However, in many regions of the world the only natural habitats that can be spared are fragments within landscapes dominated by agriculture. Therefore, land-sparing arguments hinge on land-use intensification having low spillover effects into adjacent protected areas, otherwise net conservation gains will diminish with increasing intensification. We test, for the first time, whether the degree of spillover from farmland into adjacent natural habitats scales in magnitude with increasing land-use intensity. We identified a continuous land-use intensity gradient across pastoral farming systems in New Zealand (based on 13 components of farmer input and soil biogeochemistry variables, and measured cumulative off-site spillover effects of fertilisers and livestock on soil biogeochemistry in 21 adjacent forest remnants. Ten of 11 measured soil properties differed significantly between remnants and intact-forest reference sites, for both fenced and unfenced remnants, at both edge and interior. For seven variables, the magnitude of effects scaled significantly with magnitude of surrounding land-use intensity, through complex interactions with fencing and edge effects. In particular, total C, total N, δ15N, total P and heavy-metal contaminants of phosphate fertilizers (Cd and U increased significantly within remnants in response to increasing land-use intensity, and these effects were exacerbated in unfenced relative to fenced remnants. This suggests movement of livestock into surrounding natural habitats is a significant component of agricultural spillover, but pervasive changes in soil biogeochemistry still occur through nutrient spillover channels alone

  15. Spatial variation of dung beetle assemblages associated with forest structure in remnants of southern Brazilian Atlantic Forest

    Directory of Open Access Journals (Sweden)

    Pedro Giovâni da Silva

    2016-01-01

    Full Text Available The Brazilian Atlantic Forest is one of the world's biodiversity hotspots, and is currently highly fragmented and disturbed due to human activities. Variation in environmental conditions in the Atlantic Forest can influence the distribution of species, which may show associations with some environmental features. Dung beetles (Coleoptera: Scarabaeinae are insects that act in nutrient cycling via organic matter decomposition and have been used for monitoring environmental changes. The aim of this study is to identify associations between the spatial distribution of dung beetle species and Atlantic Forest structure. The spatial distribution of some dung beetle species was associated with structural forest features. The number of species among the sampling sites ranged widely, and few species were found in all remnant areas. Principal coordinates analysis indicated that species composition, abundance and biomass showed a spatially structured distribution, and these results were corroborated by permutational multivariate analysis of variance. The indicator value index and redundancy analysis showed an association of several dung beetle species with some explanatory environmental variables related to Atlantic Forest structure. This work demonstrated the existence of a spatially structured distribution of dung beetles, with significant associations between several species and forest structure in Atlantic Forest remnants from Southern Brazil. Keywords: Beta diversity, Species composition, Species diversity, Spatial distribution, Tropical forest

  16. Edge effect on palm diversity in rain forest fragments in western Ecuador

    DEFF Research Database (Denmark)

    Baez, S.; Balslev, Henrik

    2007-01-01

    to be idiosyncratic and to depend on the level of disturbance at edges. This paper explores how variation in forest structure at the edges of two old-growth forest fragments in a tropical rain forest in western Ecuador affects palms of different species, life-forms, and size classes. We investigate (1) how edge...

  17. Abiotic factors drives floristic variations of fern’s metacommunity in an Atlantic Forest remnant

    OpenAIRE

    L. E. N. Costa; R. P. Farias; A. C. P. Santiago; I. A. A. Silva; I. C. L. Barros

    2018-01-01

    Abstract We analyzed floristic variations in fern’s metacommunity at the local scale and their relationship with abiotic factors in an Atlantic Forest remnant of northeastern Brazil. Floristic and environmental variations were accessed on ten plots of 10 × 20 m. We performed cluster analyses, based on Bray-Curtis dissimilarity index to establish the floristic relationship. The influence of abiotic factors: luminosity, temperature, relative air humidity and relative soil moisture was evaluated...

  18. RAIN

    DEFF Research Database (Denmark)

    Monti, Matteo; Rasmussen, Steen

    2017-01-01

    We summarize the results and perspectives from a companion article, where we presented and evaluated an alternative architecture for data storage in distributed networks. We name the bio-inspired architecture RAIN, and it offers file storage service that, in contrast with current centralized clou...... will integrate multiple current and future infrastructures ranging from online services and cryptocurrency to parts of government administration....

  19. Odd man out : why are there fewer plant species in African rain forests ?

    OpenAIRE

    Couvreur, Thomas

    2015-01-01

    Although tropical rain forests represent the most species-rich terrestrial ecosystem on the planet, the three main rain forest regions (Neotropics, South-East Asia and continental Africa) are not equally diverse. Africa has been labeled the "odd man out" because of its perceived lower species diversity when compared to the Neotropics or South-East Asia. Understanding why, within a biome, certain regions have higher or lower species diversity provides important insights into the evolution of b...

  20. Forest remnants enhance wild pollinator visits to cashew flowers and mitigate pollination deficit in NE Brazil

    Directory of Open Access Journals (Sweden)

    Breno Magalhães Freitas

    2014-02-01

    Full Text Available Pollination deficit could cause low yields in cashew (Anacardium occidentale and it is possible that deforestation surrounding cashew plantations may prevent effective pollinators from visiting cashew flowers and contribute to this deficit. In the present work, we investigated the proximity effect of small and large forest fragments on the abundance and flower visits by feral Apis mellifera and wild native pollinators to cashew flowers and their interactions with yield in cashew plantations. Cashew nut yield was highest when plantations bordered a small forest fragment and were close to the large forest fragment. Yield from plantations that did not border small forest fragments but were close to the large forest fragment did not differ to yield from plantations at a greater distance to the large forest fragment. Flower visits by wild native pollinators, mainly Trigona spinipes, were negatively affected by distance to the large forest remnant and their numbers were directly correlated to nut yield. The number of A. mellifera visiting cashew flowers did not change significantly with distance to forest fragments, nor was it correlated with yield. We conclude that increasing the number of wild pollinator visits may increase yield, and proximity to large forest fragments are important for this.

  1. Are we headed towards the defaunation of the last large Atlantic Forest remnants? Poaching activities in one of the largest remnants of the Tabuleiro forests in southeastern Brazil.

    Science.gov (United States)

    Sousa, José Adelson C; Srbek-Araujo, Ana C

    2017-03-01

    Hunting is a problem to animal conservation in different parts of the world and it has caused the local extinction of several species. The aim of this study was to characterize the poaching activities in one of the main tabuleiro forest remnants of Brazil, the Linhares-Sooretama Block (LSB). Poaching records from 2010 to 2013 were gathered from the agencies responsible for monitoring and combating environmental crimes in the LSB. A total of 693 records (mean = 173 events/year) were collected involving direct (hunted animals, firearms, handmade firearms, traps, poachers, and various hunting supplies) and indirect (tree stands, baits, and poacher signs) evidences of poaching. No differences in the monthly cumulative number of records were found among years, but the distribution of records differed according to the type of evidence. A total of 40 animal seizure events were recorded involving a total of at least 15 taxa directly affected by poaching (reptiles = 2, birds = 6, mammals = 7) and 75 individuals seized (19 individuals/year). Five of the poached species are threatened. Lowland paca (Cuniculus paca) and armadillos were the most poached mammals in the region. Most of the poachers conduct such activities for fun (entertainment) and/or professionally (commercial hunting). The collected data show an approximately 32% increase in the number of poaching events in the region compared with the historical data available for LSB. It may have resulted from a gradual decrease in protection, both in terms of the number of agents deployed and the levels of effort of the teams, which began in 2009. The data demonstrate that poaching is a significant threat to the conservation of the LSB fauna, as it is in other Atlantic Forest remnants and in other regions of the world. Protection activities must be intensified to effectively combat the impacts of poaching in the LSB region, thereby contributing to the conservation of species in one of the few Atlantic Forest

  2. Establishing a long-term permanent plot in remnant forest of Cibodas Botanic Garden, West Java

    Directory of Open Access Journals (Sweden)

    ZAENAL MUTAQIEN

    2011-10-01

    Full Text Available Mutaqien Z, Zuhri M (2011 Establishing a long-term permanent plot in remnant forest of Cibodas Botanic Garden, West Java. Biodiversitas 12: 218-224. Cibodas Botanic Garden (CBG has unique characters; almost 10% of which is forested area adjacent to the natural forest of Mt. Gede Pangrango National Park. The area is a transition between natural forest and artificial habitat which mostly consists of exotic plant species. The permanent plot in CBG was established in 2007-2009. Two hundred and eighty four units of 10x10 square meters sub-plot were established in four locations, i.e. Wornojiwo, Kompos, Jalan Akar, and Lumut forest. Vegetation analyses were conducted for trees, saplings, shrubs, and herb species. The inventory found 137 species plants consisting of 74 tree species dominated by Villebrunea rubescens (Bl. Bl. and Ostodes paniculata Bl., 30 shrub species dominated by Strobilanthes hamiltoniana (Steud., 24 herb species dominated by Cyrtandra picta Bl., 6 fern species mainly consisted of Diplazium pallidum Moore, and 3 climber species dominated by Calamus reinwardtii Mart. In comparison with the natural forest of Mt. Gede Pangrango National Park, the CBG permanent plot showed a good representative of the vegetation of lower montane forest. A regular monitoring during the successive years is needed to maintain diversity, monitor forest dynamics and anticipate the spread of invasive plant from CBG.

  3. Evaporation from a tropical rain forest, Luquillo Experimental Forest, eastern Puerto Rico

    Science.gov (United States)

    Schellekens, J.; Bruijnzeel, L. A.; Scatena, F. N.; Bink, N. J.; Holwerda, F.

    2000-08-01

    Evaporation losses from a watertight 6.34 ha rain forest catchment under wet maritime tropical conditions in the Luquillo Experimental Forest, Puerto Rico, were determined using complementary hydrological and micrometeorological techniques during 1996 and 1997. At 6.6 mm d-1 for 1996 and 6.0 mm d-1 for 1997, the average evapotranspiration (ET) of the forest is exceptionally high. Rainfall interception (Ei), as evaluated from weekly throughfall measurements and an average stemflow fraction of 2.3%, accounted for much (62-74%) of the ET at 4.9 mm d-1 in 1996 and 3.7 mm d-1 in 1997. Average transpiration rates (Et) according to a combination of the temperature fluctuation method and the Penman-Monteith equation were modest at 2.2 mm d-1 and 2.4 mm d-1 in 1996 and 1997, respectively. Both estimates compared reasonably well with the water-budget-based estimates (ET - Ei) of 1.7 mm d-1 and 2.2 mm d-1. Inferred rates of wet canopy evaporation were roughly 4 to 5 times those predicted by the Penman-Monteith equation, with nighttime rates very similar to daytime rates, suggesting radiant energy is not the dominant controlling factor. A combination of advected energy from the nearby Atlantic Ocean, low aerodynamic resistance, plus frequent low-intensity rain is thought to be the most likely explanation of the observed discrepancy between measured and estimated Ei.

  4. Explosive radiation of Malpighiales supports a mid-cretaceous origin of modern tropical rain forests.

    Science.gov (United States)

    Davis, Charles C; Webb, Campbell O; Wurdack, Kenneth J; Jaramillo, Carlos A; Donoghue, Michael J

    2005-03-01

    Fossil data have been interpreted as indicating that Late Cretaceous tropical forests were open and dry adapted and that modern closed-canopy rain forest did not originate until after the Cretaceous-Tertiary (K/T) boundary. However, some mid-Cretaceous leaf floras have been interpreted as rain forest. Molecular divergence-time estimates within the clade Malpighiales, which constitute a large percentage of species in the shaded, shrub, and small tree layer in tropical rain forests worldwide, provide new tests of these hypotheses. We estimate that all 28 major lineages (i.e., traditionally recognized families) within this clade originated in tropical rain forest well before the Tertiary, mostly during the Albian and Cenomanian (112-94 Ma). Their rapid rise in the mid-Cretaceous may have resulted from the origin of adaptations to survive and reproduce under a closed forest canopy. This pattern may also be paralleled by other similarly diverse lineages and supports fossil indications that closed-canopy tropical rain forests existed well before the K/T boundary. This case illustrates that dated phylogenies can provide an important new source of evidence bearing on the timing of major environmental changes, which may be especially useful when fossil evidence is limited or controversial.

  5. The odd man out? Might climate explain the lower tree alpha-diversity of African rain forests relative to Amazonian rain forests?

    NARCIS (Netherlands)

    Parmentier, I.; Malhi, Y.; Senterre, B.; Whittaker, R.J.; Alonso, A.; Balinga, M.P.B.; Bakayoko, A.; Bongers, F.J.J.M.; Chatelain, C.; Comiskey, J.; Cortay, R.; Djuikouo Kamdem, M.N.; Doucet, J.L.; Gauier, L.; Hawthorne, W.D.; Issembe, Y.A.; Kouamé, F.N.; Kouka, L.; Leal, M.E.; Lejoly, J.; Lewis, S.L.; Newbery, D.; Nusbaumer, L.; Parren, M.P.E.; Peh, K.S.H.; Phillips, O.L.; Sheil, D.; Sonké, B.; Sosef, M.S.M.; Sunderland, T.; Stropp, J.; Steege, ter H.; Swaine, M.; Tchouto, P.; Gemerden, van B.S.; Valkenburg, van J.; Wöll, H.

    2007-01-01

    1. Comparative analyses of diversity variation among and between regions allow testing of alternative explanatory models and ideas. Here, we explore the relationships between the tree alpha-diversity of small rain forest plots in Africa and in Amazonia and climatic variables, to test the explanatory

  6. Foliar and ecosystem respiration in an old-growth tropical rain forest

    Science.gov (United States)

    Molly A. Cavaleri; Steven F. Oberbauer; Michael G. Ryan

    2008-01-01

    Foliar respiration is a major component of ecosystem respiration, yet extrapolations are often uncertain in tropical forests because of indirect estimates of leaf area index (LAI).A portable tower was used to directly measure LAI and night-time foliar respiration from 52 vertical transects throughout an old-growth tropical rain forest in Costa Rica. In this study, we (...

  7. Response of soil respiration to acid rain in forests of different maturity in southern China.

    Directory of Open Access Journals (Sweden)

    Guohua Liang

    Full Text Available The response of soil respiration to acid rain in forests, especially in forests of different maturity, is poorly understood in southern China despite the fact that acid rain has become a serious environmental threat in this region in recent years. Here, we investigated this issue in three subtropical forests of different maturity [i.e. a young pine forest (PF, a transitional mixed conifer and broadleaf forest (MF and an old-growth broadleaved forest (BF] in southern China. Soil respiration was measured over two years under four simulated acid rain (SAR treatments (CK, the local lake water, pH 4.5; T1, water pH 4.0; T2, water pH 3.5; and T3, water pH 3.0. Results indicated that SAR did not significantly affect soil respiration in the PF, whereas it significantly reduced soil respiration in the MF and the BF. The depressed effects on both forests occurred mostly in the warm-wet seasons and were correlated with a decrease in soil microbial activity and in fine root biomass caused by soil acidification under SAR. The sensitivity of the response of soil respiration to SAR showed an increasing trend with the progressive maturity of the three forests, which may result from their differences in acid buffering ability in soil and in litter layer. These results indicated that the depressed effect of acid rain on soil respiration in southern China may be more pronounced in the future in light of the projected change in forest maturity. However, due to the nature of this field study with chronosequence design and the related pseudoreplication for forest types, this inference should be read with caution. Further studies are needed to draw rigorous conclusions regarding the response differences among forests of different maturity using replicated forest types.

  8. Nutrient additions to a tropical rain forest drive substantial soil carbon dioxide losses to the atmosphere

    OpenAIRE

    Cleveland, Cory C.; Townsend, Alan R.

    2006-01-01

    Terrestrial biosphere–atmosphere carbon dioxide (CO2) exchange is dominated by tropical forests, where photosynthetic carbon (C) uptake is thought to be phosphorus (P)-limited. In P-poor tropical forests, P may also limit organic matter decomposition and soil C losses. We conducted a field-fertilization experiment to show that P fertilization stimulates soil respiration in a lowland tropical rain forest in Costa Rica. In the early wet season, when soluble organic matter inputs to soil are hig...

  9. Response of soil respiration to acid rain in forests of different maturity in southern China.

    Science.gov (United States)

    Liang, Guohua; Liu, Xingzhao; Chen, Xiaomei; Qiu, Qingyan; Zhang, Deqiang; Chu, Guowei; Liu, Juxiu; Liu, Shizhong; Zhou, Guoyi

    2013-01-01

    The response of soil respiration to acid rain in forests, especially in forests of different maturity, is poorly understood in southern China despite the fact that acid rain has become a serious environmental threat in this region in recent years. Here, we investigated this issue in three subtropical forests of different maturity [i.e. a young pine forest (PF), a transitional mixed conifer and broadleaf forest (MF) and an old-growth broadleaved forest (BF)] in southern China. Soil respiration was measured over two years under four simulated acid rain (SAR) treatments (CK, the local lake water, pH 4.5; T1, water pH 4.0; T2, water pH 3.5; and T3, water pH 3.0). Results indicated that SAR did not significantly affect soil respiration in the PF, whereas it significantly reduced soil respiration in the MF and the BF. The depressed effects on both forests occurred mostly in the warm-wet seasons and were correlated with a decrease in soil microbial activity and in fine root biomass caused by soil acidification under SAR. The sensitivity of the response of soil respiration to SAR showed an increasing trend with the progressive maturity of the three forests, which may result from their differences in acid buffering ability in soil and in litter layer. These results indicated that the depressed effect of acid rain on soil respiration in southern China may be more pronounced in the future in light of the projected change in forest maturity. However, due to the nature of this field study with chronosequence design and the related pseudoreplication for forest types, this inference should be read with caution. Further studies are needed to draw rigorous conclusions regarding the response differences among forests of different maturity using replicated forest types.

  10. Arbuscular-mycorrhizal networks inhibit Eucalyptus tetrodonta seedlings in rain forest soil microcosms.

    Directory of Open Access Journals (Sweden)

    David P Janos

    Full Text Available Eucalyptus tetrodonta, a co-dominant tree species of tropical, northern Australian savannas, does not invade adjacent monsoon rain forest unless the forest is burnt intensely. Such facilitation by fire of seedling establishment is known as the "ashbed effect." Because the ashbed effect might involve disruption of common mycorrhizal networks, we hypothesized that in the absence of fire, intact rain forest arbuscular mycorrhizal (AM networks inhibit E. tetrodonta seedlings. Although arbuscular mycorrhizas predominate in the rain forest, common tree species of the northern Australian savannas (including adult E. tetrodonta host ectomycorrhizas. To test our hypothesis, we grew E. tetrodonta and Ceiba pentandra (an AM-responsive species used to confirm treatments separately in microcosms of ambient or methyl-bromide fumigated rain forest soil with or without severing potential mycorrhizal fungus connections to an AM nurse plant, Litsea glutinosa. As expected, C. pentandra formed mycorrhizas in all treatments but had the most root colonization and grew fastest in ambient soil. E. tetrodonta seedlings also formed AM in all treatments, but severing hyphae in fumigated soil produced the least colonization and the best growth. Three of ten E. tetrodonta seedlings in ambient soil with intact network hyphae died. Because foliar chlorosis was symptomatic of iron deficiency, after 130 days we began to fertilize half the E. tetrodonta seedlings in ambient soil with an iron solution. Iron fertilization completely remedied chlorosis and stimulated leaf growth. Our microcosm results suggest that in intact rain forest, common AM networks mediate belowground competition and AM fungi may exacerbate iron deficiency, thereby enhancing resistance to E. tetrodonta invasion. Common AM networks-previously unrecognized as contributors to the ashbed effect-probably help to maintain the rain forest-savanna boundary.

  11. Hydrological consequences of land-use change from forest to pasture in the Atlantic rain forest region

    Directory of Open Access Journals (Sweden)

    Luiz Antonio Martinelli

    2012-12-01

    Full Text Available The Atlantic rain forest is the most endangered ecosystem in Brazil. Its degradation has started since 1500 when the European settlers arrived. Despite of all land use changes that have occurred, hydrological studies carried out in this biome have been limited to hydrological functioning of rain forests only. In order to understand the hydrological consequences of land-use change from forest to pasture, we described the hydrological functioning of a pasture catchment that was previously covered by tropical rain forest. To reach this goal we measured the precipitation, soil matric potential, discharge, surface runoff and water table levels during one year. The results indicated that there is a decrease in surface soil saturated hydraulic conductivity. However, as low intensity rainfall prevails, the lower water conductivity does not necessarily leads to a substantially higher surface runoff generation. Regarding soil water matric potential, the pasture presented higher moisture levels than forest during the dry season. This increase in soil moisture implies in higher water table recharge that, in turn, explain the higher runoff ratio. This way, land-use change conversion from forest to pasture implies a higher annual streamflow in pasture catchments. Nonetheless, this increase in runoff due to forest conversion to pasture implies in losses of biological diversity as well as lower soil protection.

  12. Pentatomidae (Hemiptera: Heteroptera) in Herbaceous and Shrub Strata of Atlantic Forest Remnants in Northeastern Brazil.

    Science.gov (United States)

    Firmino, João V L; Mendonça, Milton D S; Lima, Iracilda M M; Grazia, Jocelia

    2017-06-01

    Most pentatomids are phytophagous, many of which are economically important crop pests. The family may also be a potentially important group to monitor the health of neotropical forests. However, there is a lack of biological inventories of Pentatomidae, especially in forest remnants of the Brazilian Atlantic forest. This is the first systematic survey of pentatomids reported in three Atlantic forest fragments in northeastern Brazil. In total, 997 individuals belonging to 38 species were recorded, some of which are considered economically important pests. Singletons and doubletons represented 45.9% of all species collected. The most abundant genera were Mormidea Amyot & Serville, 1843; Stictochilus Bergroth, 1918; Xynocoris Garbelotto & Campos 2014; and Edessa F., 1803. Species richness differed among fragments, with a richness gradient correlated with decreased urbanization and increased fragment size. The species abundance distribution fitted the logseries function but not the lognormal, in accordance with what is found for other assemblages in southern Brazil. Species composition also changed, in association with changes in temperature (revealed by the canonical correspondence analysis [CCA]), among fragments. Murici is one of the last remaining dense forests with high plant diversity in the region, having higher pentatomid species richness and a distinctive fauna. This first diversity study for Pentatomidae in fragments of tropical Atlantic Forest in northeastern Brazil reveals richness comparable with those from subtropical southern Brazil, with some species in common as well. © The Authors 2017. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  13. Ecological studies on rain forest in Northern Suriname

    NARCIS (Netherlands)

    Schulz, J.P.

    1960-01-01

    During the years 1955-1957 ecological data were collected in various types of mesophytic forest occurring in the northern half of central Suriname (fig. 1). Physiognomically as well as floristically these forests correspond with the type of vegetation which in the other parts of tropical America

  14. Prolonged acid rain facilitates soil organic carbon accumulation in a mature forest in Southern China.

    Science.gov (United States)

    Wu, Jianping; Liang, Guohua; Hui, Dafeng; Deng, Qi; Xiong, Xin; Qiu, Qingyan; Liu, Juxiu; Chu, Guowei; Zhou, Guoyi; Zhang, Deqiang

    2016-02-15

    With the continuing increase in anthropogenic activities, acid rain remains a serious environmental threat, especially in the fast developing areas such as southern China. To detect how prolonged deposition of acid rain would influence soil organic carbon accumulation in mature subtropical forests, we conducted a field experiment with simulated acid rain (SAR) treatments in a monsoon evergreen broadleaf forest at Dinghushan National Nature Reserve in southern China. Four levels of SAR treatments were set by irrigating plants with water of different pH values: CK (the control, local lake water, pH ≈ 4.5), T1 (water pH=4.0), T2 (water pH=3.5), and T3 (water pH=3.0). Results showed reduced pH measurements in the topsoil exposed to simulated acid rains due to soil acidification. Soil respiration, soil microbial biomass and litter decomposition rates were significantly decreased by the SAR treatments. As a result, T3 treatment significantly increased the total organic carbon by 24.5% in the topsoil compared to the control. Furthermore, surface soil became more stable as more recalcitrant organic matter was generated under the SAR treatments. Our results suggest that prolonged acid rain exposure may have the potential to facilitate soil organic carbon accumulation in the subtropical forest in southern China. Copyright © 2015 Elsevier B.V. All rights reserved.

  15. Differences in seed rain composition in small and large fragments in the northeast Brazilian Atlantic Forest.

    Science.gov (United States)

    Knörr, U C; Gottsberger, G

    2012-09-01

    Tropical forests are seriously threatened by fragmentation and habitat loss. The impact of fragment size and forest configuration on the composition of seed rain is insufficiently studied. For the present study, seed rain composition of small and large forest fragments (8-388 ha) was assessed in order to identify variations in seed abundance, species richness, seed size and dispersal mode. Seed rain was documented during a 1-year period in three large and four small Atlantic Forest fragments that are isolated by a sugarcane matrix. Total seed rain included 20,518 seeds of 149 species of trees, shrubs, palms, lianas and herbs. Most species and seeds were animal-dispersed. A significant difference in the proportion of seeds and species within different categories of seed size was found between small and large fragments. Small fragments received significantly more very small-sized seeds (1.5 cm) that were generally very rare, with only one species in small and eight in large fragments. We found a negative correlation between the inflow of small-sized seeds and the percentage of forest cover. Species richness was lower in small than in large fragments, but the difference was not very pronounced. Given our results, we propose changing plant species pools through logging, tree mortality and a high inflow of pioneer species and lianas, especially in small forest fragments and areas with low forest cover. Connecting forest fragments through corridors and reforestation with local large-seeded tree species may facilitate the maintenance of species diversity. © 2012 German Botanical Society and The Royal Botanical Society of the Netherlands.

  16. Rubiaceae in Brazilian Atlantic Forest remnants: floristic similarity and implications for conservation.

    Science.gov (United States)

    de Paiva, Alessandra Marques; Barberena, Felipe Fajardo Villela Antolin; Lopes, Rosana Conrado

    2016-06-01

    Brazil holds most of the Atlantic Forest Domain and is also one of the Rubiaceae diversity centers in the Neotropics. Despite the urban expansion in the state of Rio de Janeiro, large areas of continuous vegetation with high connectivity degree can still be found. Recently, new Rubiaceae species have been described in the Rio de Janeiro flora, which present small populations and very particular distribution. The current paper analyzed the similarity in the floristic composition of the Rubiaceae in eight Atlantic Forest remnants of Rio de Janeiro state protected by Conservation Units. We also surveyed and set guidelines for conservation of microendemic species. The similarity analysis were based on previously published studies in Área de Proteção Ambiental de Grumari, Área de Proteção Ambiental Palmares, Parque Estadual da Serra da Tiririca, Parque Nacional do Itatiaia, Parque Nacional de Jurubatiba, Reserva Biológica de Poço das Antas, Reserva Biológica do Tinguá and Reserva Ecológica de Macaé de Cima - using the PAST software (“Paleontological Statistics”) with Sørensen coefficient. The floristic similarity analysis revealed two groups with distinct physiographic characteristics and different vegetation types. Group A consisted in two Restinga areas, Área de Proteção Ambiental de Grumari and Parque Nacional de Jurubatiba, which showed strong bootstrap support (98 %). Group B included forest remnants with distinct phytophisiognomies or altitudes, but with moderate bootstrap support. Low similarity levels among the eight areas were found due to the habitats’ heterogeneity. The current study pointed out 19 microendemic species from the Atlantic Forest, they present a single-site distribution or a distribution restricted to Mountain and Metropolitan regions of Rio de Janeiro state. Concerning the conservation status of microendemic species, discrepancies between the Catalogue of Flora of Rio de Janeiro and the Red Book of Brazilian Flora (two of

  17. Variation in photosynthetic light-use efficiency in a mountainous tropical rain forest in Indonesia

    DEFF Research Database (Denmark)

    Ibrom, Andreas; Oltchev, A.; June, T.

    2008-01-01

    in remote tropical areas. We used a 16-month continuous CO2 flux and meteorological dataset from a mountainous tropical rain forest in central Sulawesi, Indonesia to derive values of epsilon(Pg). and to investigate the relationship between P-g and Q(abs). Absorption was estimated with a 1D SVAT model from...

  18. The northern flying squirrel as an indicator species of temperate rain forest: test of an hypothesis.

    Science.gov (United States)

    Winston P. Smith; Scott M. Gende; Jeffrey V. Nichols

    2005-01-01

    Management indicator species (MIS) often are selected because their life history and demographics are thought to reflect a suite of ecosystem conditions that are too difficult or costly to measure directly. The northern flying squirrel (Glaucomys sabrinus) has been proposed as an MIS of temperate rain forest of southeastern Alaska based on previous...

  19. Rain Forest Tourism - Estimating the Benefits of Tourism Development in a New National Park in Madagascar

    Science.gov (United States)

    D. Evan Mercer; R. Kramer; N. Sharma

    1995-01-01

    Travel cost and contingent valuation methods are applied to the problem of estimating the potential consumer surplus available to international nature tourists from a rain forest conservation project in Madagascar. Data are derived from surveys of nature tourists in Madagascar and international, nature tourism professionals in the U.S. and Europe. Typical trip travel...

  20. Architecture of 53 rain forest tree species differing in adult stature and shade tolerance

    NARCIS (Netherlands)

    Poorter, L.; Bongers, F.J.J.M.; Sterck, F.J.; Wöll, H.

    2003-01-01

    Tree architecture determines a tree's light capture, stability, and efficiency of crown growth. The hypothesis that light demand and adult stature of tree species within a community, independently of each other, determine species' architectural traits was tested by comparing 53 Liberian rain forest

  1. Little ecological divergence associated with speciation in two African rain forest tree genera

    NARCIS (Netherlands)

    Couvreur, T.L.P.; Porter-Morgan, H.; Wieringa, J.J.; Chatrou, L.W.

    2011-01-01

    Background - The tropical rain forests (TRF) of Africa are the second largest block of this biome after the Amazon and exhibit high levels of plant endemism and diversity. Two main hypotheses have been advanced to explain speciation processes that have led to this high level of biodiversity:

  2. Evaporation from rain-wetted forest in relation to canopy wetness, canopy cover, and net radiation

    NARCIS (Netherlands)

    Klaassen, W.

    2001-01-01

    Evaporation from wet canopies is commonly calculated using E-PM, the Penman-Monteith equation with zero surface resistance. However, several observations show a lower evaporation from rain-wetted forest. Possible causes for the difference between E-PM and experiments are evaluated to provide rules

  3. Diversity patterns in the flora of the Campo-Ma'an rain forest, Cameroon: do tree species tell it all?

    NARCIS (Netherlands)

    Tchouto, M.G.P.; Boer, de W.F.; Wilde, de J.J.F.E.; Maesen, van der L.J.G.

    2006-01-01

    This study describes diversity patterns in the flora of the Campo-Ma¿an rain forest, in south Cameroon. In this area, the structure and composition of the forests change progressively from the coastal forest on sandy shorelines through the lowland evergreen forest rich in Caesalpinioideae with

  4. Abiotic factors drives floristic variations of fern's metacommunity in an Atlantic Forest remnant.

    Science.gov (United States)

    Costa, L E N; Farias, R P; Santiago, A C P; Silva, I A A; Barros, I C L

    2018-02-15

    We analyzed floristic variations in fern's metacommunity at the local scale and their relationship with abiotic factors in an Atlantic Forest remnant of northeastern Brazil. Floristic and environmental variations were accessed on ten plots of 10 × 20 m. We performed cluster analyses, based on Bray-Curtis dissimilarity index to establish the floristic relationship. The influence of abiotic factors: luminosity, temperature, relative air humidity and relative soil moisture was evaluated from a redundancy analysis. We found 24 species belonging to 20 genera and 12 families. The fern's flora showed high floristic heterogeneity (>75% for most of the plot's associations). The fern's metacommunity was structured along an abiotic gradient modulated by temperature, luminosity, and relative soil moisture.

  5. Abiotic factors drives floristic variations of fern’s metacommunity in an Atlantic Forest remnant

    Directory of Open Access Journals (Sweden)

    L. E. N. Costa

    2018-02-01

    Full Text Available Abstract We analyzed floristic variations in fern’s metacommunity at the local scale and their relationship with abiotic factors in an Atlantic Forest remnant of northeastern Brazil. Floristic and environmental variations were accessed on ten plots of 10 × 20 m. We performed cluster analyses, based on Bray-Curtis dissimilarity index to establish the floristic relationship. The influence of abiotic factors: luminosity, temperature, relative air humidity and relative soil moisture was evaluated from a redundancy analysis. We found 24 species belonging to 20 genera and 12 families. The fern’s flora showed high floristic heterogeneity (>75% for most of the plot’s associations. The fern’s metacommunity was structured along an abiotic gradient modulated by temperature, luminosity, and relative soil moisture.

  6. Floristic structure and biomass distribution of a tropical seasonal rain forest in Xishuangbanna, southwest China

    Energy Technology Data Exchange (ETDEWEB)

    Shanmughavel, P.; Zheng Zheng; Sha Liqing; Cao Min [Chinese Academy of Sciences, Kunming (China). Dept. of Forest Ecology

    2001-07-01

    The aim of this research was to study the forest community structure, tree species diversity and biomass production of a tropical seasonal rain forest in Xishuangbanna, southwest China. The community structure showed a diversified species composition and supported many species of economic significance. This tropical rain forest in closely related to Malaysian forests. The biomass and its distribution were studied using standard regression analysis and the clear-cut method for shrubs and herbs. The total biomass was 360.9 t/ha and its allocation in different layers was: tree layer 352.5 t/ha, shrub layer 4.7 t/ha, liana 3.1 t/ha and herb layer 0.5 t/ha. Most of the biomass was concentrated in the trees: stem 241.2 t/ha, root 69.6 t/ha, branch 37.2 t/ha and leaves 4.3 t/ha. The DBH class allocation of the tree biomass was concentrated in the middle DBH class. The biomass of six DBH classes from 20 to 80 cm was 255.4 t/ha. There are twenty-six species with biomass over 0.5% of the total biomass of the tree layer, and three species with biomass over 5%, i.e., Pometia tomentosa, Barringtonia macrostachya (5.4%) and Terminalia myriocarpa (5.2%). Data on stem, branch, leaves and root of the individual tree species were used to develop regression models. D{sup 2}H was found to be the best estimator of the biomass in this tropical rain forest. However, higher biomass figures have been reported from tropical forests elsewhere e.g., 415-520 t/ha in the tropical forests of Cambodia, the tropical moist mixed dipterocarp forests, and the tropical moist logged moist evergreen-high, medium, and low yield forests of Sri Lanka. In some forests, lower accumulation of biomass was reported, e.g., 10-295 t/ha in the tropical moist forests of Bangladesh, the tropical moist dense forest of Cambodia, the tropical dry forests of India, the tropical moist forests of Peninsular-Malaysia, the tropical moist mixed dipterocarp forests of Sarawak-Malaysia, the tropical evergreen forests of

  7. Effect of urbanization on the structure and functional traits of remnant subtropical evergreen broad-leaved forests in South China

    Science.gov (United States)

    Liujing Huang; Hongfeng Chen; Hai Ren; Jun Wang; Qinfeng Guo

    2013-01-01

    We investigated the effects of major environmental drivers associated with urbanization on species diversity and plant functional traits (PFTs) in the remnant subtropical evergreen broad-leaved forests in Metropolitan Guangzhou (Guangdong, China). Twenty environmental factors including topography, light, and soil properties were used to quantify the effects of...

  8. Spatio-temporal dynamics of the tropical rain forest

    Energy Technology Data Exchange (ETDEWEB)

    Chave, J. [CEN Saclay, Gif-sur-Yvette (France). Service de Physique de l' Etat Condense

    2000-07-01

    Mechanisms which drive the dynamics of forest ecosystems are complex, from seedling establishment to pollination, and seed dispersal by animals, running water or wind. These processes are more complex when the ecosystem shelters a large number of species and of vegetative forms, as it is the case in the tropical rainforest. To take them into account, we must develop and use models. I present a review of the fundamental mechanisms for the of a natural forest dynamics - photosynthesis, tree growth, recruitment and mortality - as well as a description of the past and of the present of tropical rainforests. This information is used to develop a spatially-explicit and individual-based forest model. Simplified models are deduced from it, and they serve to address more specific issues, such as the resilience of the forest to climate disturbances, or savanna-forest dynamics. The last topic is related to the spatio-temporal description of tropical plant biodiversity. A detailed introduction to the problem is provided, and models accounting for the maintenance of diversity are compared. These models include non spatial as well a spatial approaches (branching anihilating random walks and voter model with mutation). (orig.)

  9. On the occurrence of bryophytes and macrolichens in different lowland rain forest types at Mabura Hill, Guyana

    OpenAIRE

    Cornelissen, J. Hans C.; Gradstein, Stephan Robbert

    1990-01-01

    A floristic and ecological study of bryophytes and macrolichens in different lowland rain forest types around Mabura Hill, Guyana, South America, yielded 170 species: 52 mosses, 82 liverworts and 36 macrolichens. Lejeuneaceae account for about 30% of the species and are the dominant cryptogamic family of the lowland rain forest. Special attention was paid to the flora of the forest canopy, by using mountaineering techniques. It appeared that 50% of the bryophyte species and 86% of the macroli...

  10. Agaricomycetes in low land and montane Atlantic Rain Forest in Northeast Brazil

    Directory of Open Access Journals (Sweden)

    Tatiana Gibertoni

    2014-10-01

    Full Text Available The Atlantic Rain Forest represents a group of extra-amazonic forests, among which the coastal and montane (“brejos de altitude” are the most common in Northeast Brazil. Between 2011 and 2013, 110 field trips were performed in nine reserves in the domain of the Atlantic Rain Forest. Two thousand two hundred sixty three Agaricomycetes were collected and represented 271 species, among which several new species to science, new occurrences to the continent, country, region, biome and States were found. Besides recently collected material, 309 exsiccates of Agaricomycetes deposited in the Herbarium URM were revised and represented 38 species, among which several new occurrences to the region and States. The results indicate the importance of the constant inventories and also of revisions of material deposited in herbaria as tools to improve the knowledge about the Brazilian micota.

  11. Biodiversity assessment of high rain forest under human activities: a ...

    African Journals Online (AJOL)

    Most of these species are under protection of International Union for Conservation of Natural Resources [Vulnerable, Endangered, Threatened species]. It is however concluded that all form of developmental operation activity at the Erinle forest have affected these conservation important species, and also transformed the ...

  12. The hummingbird community and their floral resources in an urban forest remnant in Brazil

    Directory of Open Access Journals (Sweden)

    LC. Rodrigues

    Full Text Available The temporal and spatial resource use among hummingbirds was studied over 13 months in an urban forest remnant (Prosa State Park: PSP in Campo Grande, Mato Grosso do Sul, Brazil. Hummingbird visitation was recorded at three ornithophilous and eleven non-ornithophilous species. Flower density was roughly constant during the study period, with the density of non-ornithophilous flowers being higher than that of ornithophilous ones. Mean values of nectar volume and concentration were similar between ornithophilous and non-ornithophilous species. Eight hummingbird species were observed at PSP: Amazilia fimbriata, Anthracothorax nigricollis, Chlorostilbon lucidus, Eupetomena macroura, Hylocharis chrysura, Florisuga fusca, Thalurania furcata and an unidentified species. Hummingbird visit frequencies to ornithophilous and non-ornithophilous flowers were similar. However, some non-ornithophilous species received a higher number of visits, which seems to be related to their large number of open flowers per plant per day. The number of feedings bouts of hummingbirds increased with the total number of flowers observed per focal plant. All recorded species of hummingbirds visited non-ornithophilous flowers, predominantly melittophilous and generalised entomophilous flowers. Hummingbird species recorded at PSP may be viewed as generalists, visiting a large number of non-ornithophilous species. Despite being an urban forest, PSP is relatively rich in hummingbird species, suggesting that it provides important shelter and foraging sites for hummingbirds in such an environment.

  13. The hummingbird community and their floral resources in an urban forest remnant in Brazil.

    Science.gov (United States)

    Rodrigues, L C; Araujo, A C

    2011-08-01

    The temporal and spatial resource use among hummingbirds was studied over 13 months in an urban forest remnant (Prosa State Park: PSP) in Campo Grande, Mato Grosso do Sul, Brazil. Hummingbird visitation was recorded at three ornithophilous and eleven non-ornithophilous species. Flower density was roughly constant during the study period, with the density of non-ornithophilous flowers being higher than that of ornithophilous ones. Mean values of nectar volume and concentration were similar between ornithophilous and non-ornithophilous species. Eight hummingbird species were observed at PSP: Amazilia fimbriata, Anthracothorax nigricollis, Chlorostilbon lucidus, Eupetomena macroura, Hylocharis chrysura, Florisuga fusca, Thalurania furcata and an unidentified species. Hummingbird visit frequencies to ornithophilous and non-ornithophilous flowers were similar. However, some non-ornithophilous species received a higher number of visits, which seems to be related to their large number of open flowers per plant per day. The number of feedings bouts of hummingbirds increased with the total number of flowers observed per focal plant. All recorded species of hummingbirds visited non-ornithophilous flowers, predominantly melittophilous and generalised entomophilous flowers. Hummingbird species recorded at PSP may be viewed as generalists, visiting a large number of non-ornithophilous species. Despite being an urban forest, PSP is relatively rich in hummingbird species, suggesting that it provides important shelter and foraging sites for hummingbirds in such an environment.

  14. Rain-induced changes in soil CO2 flux and microbial community composition in a tropical forest of China.

    Science.gov (United States)

    Deng, Qi; Hui, Dafeng; Chu, Guowei; Han, Xi; Zhang, Quanfa

    2017-07-17

    Rain-induced soil CO 2 pulse, a rapid excitation in soil CO 2 flux after rain, is ubiquitously observed in terrestrial ecosystems, yet the underlying mechanisms in tropical forests are still not clear. We conducted a rain simulation experiment to quantify rain-induced changes in soil CO 2 flux and microbial community composition in a tropical forest. Soil CO 2 flux rapidly increased by ~83% after rains, accompanied by increases in both bacterial (~51%) and fungal (~58%) Phospholipid Fatty Acids (PLFA) biomass. However, soil CO 2 flux and microbial community in the plots without litters showed limited response to rains. Direct releases of CO 2 from litter layer only accounted for ~19% increases in soil CO 2 flux, suggesting that the leaching of dissolved organic carbon (DOC) from litter layer to the topsoil is the major cause of rain-induced soil CO 2 pulse. In addition, rain-induced changes in soil CO 2 flux and microbial PLFA biomass decreased with increasing rain sizes, but they were positively correlated with litter-leached DOC concentration rather than total DOC flux. Our findings reveal an important role of litter-leached DOC input in regulating rain-induced soil CO 2 pulses and microbial community composition, and may have significant implications for CO 2 losses from tropical forest soils under future rainfall changes.

  15. Biomass and carbon dynamics of a tropical mountain rain forest in China.

    Science.gov (United States)

    Chen, DeXiang; Li, YiDe; Liu, HePing; Xu, Han; Xiao, WenFa; Luo, TuShou; Zhou, Zhang; Lin, MingXian

    2010-07-01

    Biometric inventories for 25 years, from 1983 to 2005, indicated that the Jianfengling tropical mountain rain forest in Hainan, China, was either a source or a modest sink of carbon. Overall, this forest was a small carbon sink with an accumulation rate of (0.56+/-0.22) Mg C ha(-1)yr(-1), integrated from the long-term measurement data of two plots (P9201 and P8302). These findings were similar to those for African and American rain forests ((0.62+/-0.23) Mg C ha(-1)yr(-1)). The carbon density varied between (201.43+/-29.38) Mg C ha(-1) and (229.16+/-39.2) Mg C ha(-1), and averaged (214.17+/-32.42) Mg C ha(-1) for plot P9201. Plot P8302, however, varied between (223.95+/-45.92) Mg C ha(-1) and (254.85+/-48.86) Mg C ha(-1), and averaged (243.35+/-47.64) Mg C ha(-1). Quadratic relationships were found between the strength of carbon sequestration and heavy rainstorms and dry months. Precipitation and evapotranspiration are two major factors controlling carbon sequestration in the tropical mountain rain forest.

  16. Regeneration of monsoon rain forest in northern Australia: the sapling bank

    Energy Technology Data Exchange (ETDEWEB)

    Russell-Smith, J. [Conservation Commission of the Northern Territory, Palmerston, NT (Australia)

    1996-12-01

    As part of a wider study examining regeneration pathways in monsoon rain forest vegetation in northern Australia, a one-off, dry season census of saplings was undertaken along transects sampled at each of 33 relatively undisturbed sites broadly representative of the range of regional monsoon rain forest vegetation. Four floristic quadrat groups were derived through TWINSPAN classification. Subsequent analyses involved: (1) comparison of mean dry season stockings of juveniles occurring in different rain forest types, and their structural and environmental correlates; (2) comparison of the contributions of different life forms, and the influence of clonal reproduction in the sapling regeneration banks of different forest types; and (3) exploration of relationships between the distributions of saplings of common tree species with respect to seed bank, floristic, structural, and environmental variables. While data presented here require cautious interpretation given that processes of seedling/sapling recruitment and mortality are highly dynamic, sapling banks were found to be most dense on coarse-textured, moist soils, and least dense on coarse-textured, seasonally dry soils. Canopy cover and fire impact were shown to be highly influential on sapling distribution, especially for saplings of tree species and those growing on seasonally dry sites. Sapling densities were little influenced by proximity to rain forest margins, except for shrubs. The potential for clonal reproduction was significantly greater on dry sites, especially for trees. The majority of saplings sampled were derived from relatively few common, non-clonal, canopy tree species. Sapling distributions of 20 out of 23 common tree species were clumped in the vicinity of conspecific adults; for most species the strength of this relationship was greater than that for any other variable. 55 refs, 1 fig, 6 tabs

  17. Mixed rain forest in southeastern Brazil: tree species regeneration and floristic relationships in a remaining stretch of forest near the city of Itaberá, Brazil

    OpenAIRE

    Ribeiro, Tiago Maciel; Ivanauskas, Natália Macedo; Martins, Sebastião Venâncio; Polisel, Rodrigo Trassi; Santos, Rochelle Lima Ramos dos; Miranda Neto, Aurino

    2013-01-01

    The aim of this work was to evaluate the floristic composition, richness, and diversity of the upper and lower strata of a stretch of mixed rain forest near the city of Itaberá, in southeastern Brazil. We also investigated the differences between this conservation area and other stretches of mixed rain forest in southern and southeastern Brazil, as well as other nearby forest formations, in terms of their floristic relationships. For our survey of the upper stratum (diameter at breast height ...

  18. Respiration rates in forest soil organic horizon materials treated with simulated acid rain

    Energy Technology Data Exchange (ETDEWEB)

    Salonius, P O

    1990-01-01

    The entire organic horizon above the mineral soil was collected under a mature black spruce (Picea mariana) stand in central New Brunswick. The organic horizon consisted of litter, fermentation, and humus layers of 1.5, 4.0, and 1.0 cm depths respectively. In concert with a series of simulated rain experiments, which dealt with the effects of acid precipitation of pH 4.6, 3.6, and 2.6 compared with controls at pH 5.6 on germination and early growth of forest tree seedlings, 30 randomly distributed, unplanted tubes in each rain chamber were exposed to treatment during each of the 5-week treatments of the various tree species. During the experiments, ca 315 mm of simulated rain was deposited on the soil surfaces in the tube containers. Marked decreases in soil microbial activity were found only with pH 2.6 rain, but responsiveness to increasing temperature was lower as rain of greater acidity was applied to the soil. Ammonium nitrogen mineralization rates were not affected by treatment of soil with acidified precipitation. 26 refs., 3 figs., 1 tab.

  19. Changes in seed rain across Atlantic Forest fragments in Northeast Brazil

    Science.gov (United States)

    Freitas, Cíntia Gomes; Dambros, Cristian; Camargo, José Luís Campana

    2013-11-01

    The objectives of this study were to characterize the distribution of seeds in remnant fragments of the Atlantic Coastal Forest and to determine whether the species diversity, seed weight, and species composition of plant communities are altered by forest fragmentation. A transect of 100 m was established in the core of each of nine fragments of Atlantic Coastal Forest in a private sugarcane plantation in the state of Alagoas, NE Brazil, and ten seed-traps were distributed at intervals of 10 m each along the transects. For 12 consecutive months seeds were collected, dried, counted, weighed, and identified to species. Seeds were assigned to categories according to their size, dispersal mode, and shade tolerance. Multiple regression models and Mantel correlation tests were used to detect the effects of fragment size, percent forest cover nearby, distance from the source area, and distance from the nearest fragment on species diversity, mean seed weight, and species similarity. Analyses were carried out for all species and for subsets corresponding to each seed category. A total of 21,985 diaspores of 190 species were collected. Most seeds were small, shade-intolerant, and zoochoric, which corroborates other studies of fragmented forest landscapes and reflects the high disturbance levels in isolated forest remnants. Our data indicate that fragmentation processes such as habitat loss can alter species diversity and species composition by reducing habitat availability and increasing fragment isolation. We also found that large-seeded species are more affected by fragment isolation, possibly because their seed dispersers rarely cross non-forested areas between fragments, while zoochoric species are more strongly affected by fragment size and apparently more strongly associated with local edaphic conditions than with distance from seed sources.

  20. Rain forest promotes trophic interactions and diversity of trap-nesting Hymenoptera in adjacent agroforestry.

    Science.gov (United States)

    Klein, Alexandra-Maria; Steffan-Dewenter, Ingolf; Tscharntke, Teja

    2006-03-01

    1. Human alteration of natural ecosystems to agroecosystems continues to accelerate in tropical countries. The resulting world-wide decline of rain forest causes a mosaic landscape, comprising simple and complex agroecosystems and patchily distributed rain forest fragments of different quality. Landscape context and agricultural management can be expected to affect both species diversity and ecosystem services by trophic interactions. 2. In Central Sulawesi, Indonesia, 24 agroforestry systems, differing in the distance to the nearest natural forest (0-1415 m), light intensity (37.5-899.6 W/m(-2)) and number of vascular plant species (7-40 species) were studied. Ten standardized trap nests for bees and wasps, made from reed and knotweed internodes, were exposed in each study site. Occupied nests were collected every month, over a period totalling 15 months. 3. A total of 13,617 brood cells were reared to produce adults of 14 trap-nesting species and 25 natural enemy species, which were mostly parasitoids. The total number of species was affected negatively by increasing distance from forest and increased with light intensity of agroforestry systems. The parasitoids in particular appeared to benefit from nearby forests. Over a 500-m distance, the number of parasitoid species decreased from eight to five, and parasitism rates from 12% to 4%. 4. The results show that diversity and parasitism, as a higher trophic interaction and ecosystem service, are enhanced by (i) improved connectivity of agroecosystems with natural habitats such as agroforestry adjacent to rain forest and (ii) management practices to increase light availability in agroforestry, which also enhances richness of flowering plants in the understorey.

  1. Influence of salinity on bacterioplankton communities from the brazilian rain forest to the coastal Atlantic Ocean

    OpenAIRE

    Silveira, Cynthia Barbosa da; Vieira, Ricardo Pilz; Cardoso, Alexander Machado; Paranhos, Rodolfo Pinheiro da Rocha; Albano, Rodolpho Mattos; Martins, Orlando Bonifácio

    2011-01-01

    BACKGROUND: Planktonic bacteria are recognized as important drivers of biogeochemical processes in all aquatic ecosystems, however, the taxa that make up these communities are poorly known. The aim of this study was to investigate bacterial communities in aquatic ecosystems at Ilha Grande, Rio de Janeiro, Brazil, a preserved insular environment of the Atlantic rain forest and how they correlate with a salinity gradient going from terrestrial aquatic habitats to the coastal Atlantic Ocean. MET...

  2. Biomass burning in the Amazon-fertilizer for the mountaineous rain forest in Ecuador.

    Science.gov (United States)

    Fabian, Peter; Kohlpaintner, Michael; Rollenbeck, Ruetger

    2005-09-01

    Biomass burning is a source of carbon, sulfur and nitrogen compounds which, along with their photochemically generated reaction products, can be transported over very long distances, even traversing oceans. Chemical analyses of rain and fogwater samples collected in the mountaineous rain forest of south Ecuador show frequent episodes of high sulfate and nitrate concentration, from which annual deposition rates are derived comparable to those found in polluted central Europe. As significant anthropogenic sources are lacking at the research site it is suspected that biomass burning upwind in the Amazon basin is the major source of the enhanced sulfate and nitrate imput. Regular rain and fogwater sampling along an altitude profile between 1800 and 3185 m has been carried out in the Podocarpus National Park close to the Rio SanFrancisco (3 degrees 58'S, 79 degrees 5'W) in southern Ecuador. pH values, electrical conductivity and chemical ion composition were measured at the TUM-WZW using standard methods. Results reported cover over one year from March 2002 until May 2003. Annual deposition rates of sulfate were calculated ranging between 4 and 13 kg S/ha year, almost as high as in polluted central Europe. Nitrogen deposition via ammonia (1.5-4.4 kg N/ha year) and nitrate (0.5-0.8 kg N/ha year) was found to be lower but still much higher than to be expected in such pristine natural forest environment. By means of back trajectory analyses it can be shown that most of the enhanced sulfur and nitrogen deposition is most likely due to forest fires far upwind of the ecuadorian sampling site, showing a seasonal variation, with sources predominantly found in the East/North East during January-March (Colombia, Venezuala, Northern Brazil) and East/SouthEast during July-September (Peru, Brazil). Our results show that biomass burning in the Amazon basin is the predominant source of sulfur and nitrogen compounds that fertilize the mountaineous rain forest in south Ecuador. The

  3. Richness and Abundance of Ichneumonidae in a Fragmented Tropical Rain Forest.

    Science.gov (United States)

    Ruiz-Guerra, B; Hanson, P; Guevara, R; Dirzo, R

    2013-10-01

    Because of the magnitude of land use currently occurring in tropical regions, the local loss of animal species due to habitat fragmentation has been widely studied, particularly in the case of vertebrates. Many invertebrate groups and the ichneumonid wasps in particular, however, have been poorly studied in this context, despite the fact that they are one of the most species-rich groups and play an important role as regulators of other insect populations. Here, we recorded the taxonomic composition of ichneumonid parasitoids and assessed their species richness, abundance, similarity, and dominance in the Los Tuxtlas tropical rain forest, Mexico. We compared two forest types: a continuous forest (640 ha) and a forest fragment (19 ha). We sampled ichneumonids using four malaise traps in both forest types during the dry (September-October) and rainy (March-April) seasons. A total of 104 individuals of Ichneumonidae belonging to 11 subfamilies, 18 genera, and 42 species were collected in the continuous forest and 11 subfamilies, 15 genera, and 24 species were collected in the forest fragment. Species richness, abundance, and diversity of ichneumonids were greater in the continuous forest than in the forest fragment. We did not detect differences between seasons. Species rank/abundance curves showed that the ichneumonid community between the forest types was different. Species similarity between forest types was low. The most dominant species in continuous forest was Neotheronia sp., whereas in the forest fragment, it was Orthocentrus sp. Changes in the ichneumonid wasp community may compromise important tropical ecosystem processes.

  4. INVASIVE PLANTS IN MOUNTAINOUS REMNANT FOREST: RECOMMENDATION FOR CHOOSING BEST DECISION FOR INVASIVE SPECIES MANAGEMENT OF Cestrum aurantiacum Lindl.

    Directory of Open Access Journals (Sweden)

    Decky Indrawan Junaedi

    2012-01-01

    Full Text Available Cestrum aurantiacum Lindl. is an exotic species found in native remnant forest of GPNP which is located inside the Cibodas Botanic Garden (CBG. Risk assessment is an important tool to choose best decision for invasive plant management.  Risk assessment analysis on C. aurantiacum in Cibodas Botanic Garden was conducted using Multi Criteria Decision Analysis (MCDA method.  Analytical Hierarchy Process (AHP used in the valuation process. Three sub-criteria used: minimizing the ecological impact, minimizing the management cost, and maximizing the public acceptance. Five management alternatives were used: do nothing (DN, eradication (E, containment (C, bio-control (BC and harvesting (H. Harvesting (H recommended as the best management decision for C. aurantiacumin at CBG remnant forest. This harvesting decision is not only creating environment/ ecosystem remediation but also as sources of fund in the management activity of the area.

  5. Communities of saprobic fungi on leaf litter of Vismia guianensis in remnants of the Brazilian Atlantic Forest

    Institute of Scientific and Technical Information of China (English)

    Loise Araujo Costa

    2017-01-01

    We examined the mycobiota associated with Vismia guianensis leaf litter in three Atlantic Forest remnants of Brazil's semiarid region.Among the study sites,two remnants were protected forest reserves,whereas the third was influenced by major anthropogenic activities.Eighteen litter samples were collected in wet and dry seasons and were processed by particle filtration technique.A total of 4750 fungal isolates of 142 taxa were identified.Species richness was higher in litter samples collected during wet season.Nonmetric multidimensional scaling multivariate analysis showed differences in the composition of fungal communities among the sampling sites and the seasons.Analysis of similarity showed that the differences were statistically significant (R =0.85;P =0.0001).Our findings revealed that spatial and temporal heterogeneity,and human activities had significant impacts on the saprobic fungi of V.guianensis leaf litter.

  6. Terrestrial mammals in an Atlantic Forest remnant, Paraná, Brazil

    Directory of Open Access Journals (Sweden)

    Gustavo Borba de Miranda

    2013-11-01

    Full Text Available The threat degree and the ecological importance of terrestrial mammals make clear the need for constantly conducting researches in order to add information to the current knowledge on this theme. This study aimed to provide a list of terrestrial mammal species in an Atlantic Forest remnant located in the Southwestern Paraná state, Brazil. Species richness and occurrence frequency were studied from April to October 2009 using two methods: direct observation and recording of traces. We registered 20 taxa distributed into 7 orders: Artiodactyla, Carnivora, Didelphimorphia, Lagomorpha, Primates, Rodentia, and Xenarthra. Among these, 4 taxa were registered either by direct observation or by recording of traces and the others were registered only through traces. The most frequently occurring species were Didelphis sp. (30.6% and Cerdocyon thous (25.6%. Out of the 20 registered taxa, Leopardus pardalis, Leopardus tigrinus, and Cuniculus paca are listed as vulnerable in the Red Book of Threatened Fauna in Parana State. Although small, the study area may assist in the availability of food and shelter for the fauna of mammals, representing an important element of the regional landscape.

  7. Diversity and aboveground biomass of lianas in the tropical seasonal rain forests of Xishuangbanna, SW China.

    Science.gov (United States)

    Lü, Xiao-Tao; Tang, Jian-Wei; Feng, Zhi-Li; Li, Mai-He

    2009-01-01

    Lianas are important components of tropical forests and have significant impacts on the diversity, structure and dynamics of tropical forests. The present study documented the liana flora in a Chinese tropical region. Species richness, abundance, size-class distribution and spatial patterns of lianas were investigated in three 1-ha plots in tropical seasonal rain forests in Xishuangbanna, SW China. All lianas with > or = 2 cm diameter at breast height (dbh) were measured, tagged and identified. A total of 458 liana stems belonging to 95 species (ranging from 38 to 50 species/ha), 59 genera and 32 families were recorded in the three plots. The most well-represented families were Loganiaceae, Annonceae, Papilionaceae, Apocynaceae and Rhamnaceae. Papilionaceae (14 species recorded) was the most important family in the study forests. The population density, basal area and importance value index (IVI) varied greatly across the three plots. Strychnos cathayensis, Byttneria grandifolia and Bousigonia mekongensis were the dominant species in terms of IVI across the three plots. The mean aboveground biomass of lianas (3 396 kg/ha) accounted for 1.4% of the total community above-ground biomass. The abundance, diversity and biomass of lianas in Xishuangbanna tropical seasonal rain forests are lower than those in tropical moist and wet forests, but higher than those in tropical dry forests. This study provides new data on lianas from a geographical region that has been little-studied. Our findings emphasize that other factors beyond the amount and seasonality of precipitation should be included when considering the liana abundance patterns across scales.

  8. Degraded tropical rain forests possess valuable carbon storage opportunities in a complex, forested landscape.

    Science.gov (United States)

    Alamgir, Mohammed; Campbell, Mason J; Turton, Stephen M; Pert, Petina L; Edwards, Will; Laurance, William F

    2016-07-20

    Tropical forests are major contributors to the terrestrial global carbon pool, but this pool is being reduced via deforestation and forest degradation. Relatively few studies have assessed carbon storage in degraded tropical forests. We sampled 37,000 m(2) of intact rainforest, degraded rainforest and sclerophyll forest across the greater Wet Tropics bioregion of northeast Australia. We compared aboveground biomass and carbon storage of the three forest types, and the effects of forest structural attributes and environmental factors that influence carbon storage. Some degraded forests were found to store much less aboveground carbon than intact rainforests, whereas others sites had similar carbon storage to primary forest. Sclerophyll forests had lower carbon storage, comparable to the most heavily degraded rainforests. Our findings indicate that under certain situations, degraded forest may store as much carbon as intact rainforests. Strategic rehabilitation of degraded forests could enhance regional carbon storage and have positive benefits for tropical biodiversity.

  9. Radioecological studies of tritium movement in a tropical rain forest

    Energy Technology Data Exchange (ETDEWEB)

    Martin, J R; Jordan, C F; Koranda, J J; Kline, J R [Bio-Medical Division, Lawrence Radiation Laboratory, University of California, Livermore, CA (United States)

    1970-05-01

    Several experiments on the movement of tritium in a tropical ecosystem have been conducted in the montane rainforest of Eastern Puerto Rico by the Bio-Medical Division of the Lawrence Radiation Laboratory, Livermore, in cooperation with the Puerto Rico Nuclear Center. Tritiated whaler was used as a tracer for water movement in: a) mature evergreen trees of the climax rainforest; b) soil and substory vegetation and c) rapidly growling successional species. A feasibility study on the Atlantic Pacific Interoceanic Canal is currently being conducted. If thermonuclear explosives were used in constructing the canal, tritium would be deposited as tritiated water and distributed among the several biological compartments of the tropical ecosystem in that area. The main hydrogen compartments are water in the soil and in leaves, limbs and wood of forest trees. Organic tissue hydrogen comprises another compartment. In the tree experiment, tritiated water was injected directly into several species of mature, broad leaved evergreen tropical trees. Transpiration and residence time for tritium was determined from analyses of leaves sampled during a several month period. Transpiration ranged from 4 ml/day/gm dry leaf for an understory Dacryodes excelsa to 10.0 and 13.8 ml/day/gm dry leaf for a mature Sloanea berteriana and D. excelsa, respectively. Mean residence time for the S. berteriana was 3.9 {+-} 0.2 days and the understory and mature D. excelsa values were 9.5 {+-} 0.4 and 11.0 {+-} 0. 6 days, respectively. In another experiment, tritiated water was sprinkled over a 3.68 m{sup 2} plot and its movement down into the soil and up into the vegetation growing on the plot was traced. The pattern of water movement in the soil was clearly demonstrated. The mean residence time for tritium in the soil and in trees was found to be 42 {+-} 2 days and 67 {+-} 9 days, respectively. The residence time for tritium in the trees in this experiment was considerably longer than for the single

  10. Radioecological studies of tritium movement in a tropical rain forest

    International Nuclear Information System (INIS)

    Martin, J.R.; Jordan, C.F.; Koranda, J.J.; Kline, J.R.

    1970-01-01

    Several experiments on the movement of tritium in a tropical ecosystem have been conducted in the montane rainforest of Eastern Puerto Rico by the Bio-Medical Division of the Lawrence Radiation Laboratory, Livermore, in cooperation with the Puerto Rico Nuclear Center. Tritiated whaler was used as a tracer for water movement in: a) mature evergreen trees of the climax rainforest; b) soil and substory vegetation and c) rapidly growling successional species. A feasibility study on the Atlantic Pacific Interoceanic Canal is currently being conducted. If thermonuclear explosives were used in constructing the canal, tritium would be deposited as tritiated water and distributed among the several biological compartments of the tropical ecosystem in that area. The main hydrogen compartments are water in the soil and in leaves, limbs and wood of forest trees. Organic tissue hydrogen comprises another compartment. In the tree experiment, tritiated water was injected directly into several species of mature, broad leaved evergreen tropical trees. Transpiration and residence time for tritium was determined from analyses of leaves sampled during a several month period. Transpiration ranged from 4 ml/day/gm dry leaf for an understory Dacryodes excelsa to 10.0 and 13.8 ml/day/gm dry leaf for a mature Sloanea berteriana and D. excelsa, respectively. Mean residence time for the S. berteriana was 3.9 ± 0.2 days and the understory and mature D. excelsa values were 9.5 ± 0.4 and 11.0 ± 0. 6 days, respectively. In another experiment, tritiated water was sprinkled over a 3.68 m 2 plot and its movement down into the soil and up into the vegetation growing on the plot was traced. The pattern of water movement in the soil was clearly demonstrated. The mean residence time for tritium in the soil and in trees was found to be 42 ± 2 days and 67 ± 9 days, respectively. The residence time for tritium in the trees in this experiment was considerably longer than for the single injected input

  11. The role of urban forest to reduce rain acid in urban industrial areas

    Science.gov (United States)

    Slamet, B.; Agustiarni, Y.; Hidayati; Basyuni, M.

    2018-03-01

    Urban forest has many functions mainly on improving the quality of the urban environment. One of the functions is to increase pH and reduce dangerous chemical content. The aim of the research is to find out the role of vegetation density of urban forest around the industrial area in reducing the acid rain. The condition of land cover was classified into four classes which are dense, medium, sparse and open area. The water of the throughfall and stemflow was taken from each type of land cover except in the open area. Parameters measured in this study are water acidity (pH), anion content (SO4 2- and NO3 -), cation content (Ca2+, Mg2+, and NH4 +) and electrical conductivity (EC). The results indicated that urban forest vegetation was able to increase the pH of rain water from 5.42 which is in an open area without vegetation to be 7.13 and 7.32 in dense and moderate vegetation cover by throughfall mechanism, respectively. Rain water acidity also decreased through stemflow mechanism with a pH ranged from 5.92 - 6.43. Urban forest vegetation decreased sulfate content (SO42-) from 528.67 mg/l in open area to 44 - 118 mg/l by throughfall mechanism and ranged from 90 to 366.67 mg/l through stemflow mechanism. Urban forest vegetation significantly decreased the rainwater nitrate content from 27 mg/l to 0.03 - 0.70 mg/l through the mechanism of throughfall and between 1.53 - 8.82 mg/l through the stemflow mechanism. Urban forest vegetation also increased the concentration of cations (NH4+, Ca2+, Mg2+, Na+) compared with open areas. Urban forest vegetation showed increased the electrical conductivity (EC) from 208.12 μmhos/cm to 344.67 - 902.17 μmhos/cm through the through fall mechanism and 937.67 - 1058.70 μmhos/cm through the stemflow mechanism. The study suggested that urban forests play a significant role in reducing rainwater acidity and improving the quality of rainwater that reached the soil surface.

  12. Height-related changes in leaf photosynthetic traits in diverse Bornean tropical rain forest trees.

    Science.gov (United States)

    Kenzo, Tanaka; Inoue, Yuta; Yoshimura, Mitsunori; Yamashita, Megumi; Tanaka-Oda, Ayumi; Ichie, Tomoaki

    2015-01-01

    Knowledge of variations in morphophysiological leaf traits with forest height is essential for quantifying carbon and water fluxes from forest ecosystems. Here, we examined changes in leaf traits with forest height in diverse tree species and their role in environmental acclimation in a tropical rain forest in Borneo that does not experience dry spells. Height-related changes in leaf physiological and morphological traits [e.g., maximum photosynthetic rate (Amax), stomatal conductance (gs), dark respiration rate (Rd), carbon isotope ratio (δ(13)C), nitrogen (N) content, and leaf mass per area (LMA)] from understory to emergent trees were investigated in 104 species in 29 families. We found that many leaf area-based physiological traits (e.g., A(max-area), Rd, gs), N, δ(13)C, and LMA increased linearly with tree height, while leaf mass-based physiological traits (e.g., A(max-mass)) only increased slightly. These patterns differed from other biomes such as temperate and tropical dry forests, where trees usually show decreased photosynthetic capacity (e.g., A(max-area), A(max-mass)) with height. Increases in photosynthetic capacity, LMA, and δ(13)C are favored under bright and dry upper canopy conditions with higher photosynthetic productivity and drought tolerance, whereas lower R d and LMA may improve shade tolerance in lower canopy trees. Rapid recovery of leaf midday water potential to theoretical gravity potential during the night supports the idea that the majority of trees do not suffer from strong drought stress. Overall, leaf area-based photosynthetic traits were associated with tree height and the degree of leaf drought stress, even in diverse tropical rain forest trees.

  13. Seasonal variation of ozone deposition to a tropical rain forest in southwest Amazonia

    Directory of Open Access Journals (Sweden)

    U. Rummel

    2007-10-01

    Full Text Available Within the project EUropean Studies on Trace gases and Atmospheric CHemistry as a contribution to Large-scale Biosphere-atmosphere experiment in Amazonia (LBA-EUSTACH, we performed tower-based eddy covariance measurements of O3 flux above an Amazonian primary rain forest at the end of the wet and dry season. Ozone deposition revealed distinct seasonal differences in the magnitude and diel variation. In the wet season, the rain forest was an effective O3 sink with a mean daytime (midday maximum deposition velocity of 2.3 cm s−1, and a corresponding O3 flux of −11 nmol m−2 s−1. At the end of the dry season, the ozone mixing ratio was about four times higher (up to maximum values of 80 ppb than in the wet season, as a consequence of strong regional biomass burning activity. However, the typical maximum daytime deposition flux was very similar to the wet season. This results from a strong limitation of daytime O3 deposition due to reduced plant stomatal aperture as a response to large values of the specific humidity deficit. As a result, the average midday deposition velocity in the dry burning season was only 0.5 cm s−1. The large diel ozone variation caused large canopy storage effects that masked the true diel variation of ozone deposition mechanisms in the measured eddy covariance flux, and for which corrections had to be made. In general, stomatal aperture was sufficient to explain the largest part of daytime ozone deposition. However, during nighttime, chemical reaction with nitrogen monoxide (NO was found to contribute substantially to the O3 sink in the rain forest canopy. Further contributions were from non-stomatal plant uptake and other processes that could not be clearly identified.

    Measurements, made simultaneously on a 22 years old cattle pasture enabled the spatially and temporally direct comparison of O3

  14. Effect of Simulated Acid Rain on Potential Carbon and Nitrogen Mineralization in Forest Soils

    Institute of Scientific and Technical Information of China (English)

    OUYANG Xue-Jun; ZHOU Guo-Yi; HUANG Zhong-Liang; LIU Ju-Xiu; ZHANG De-Qiang; LI Jiong

    2008-01-01

    Acid rain is a serious environmental problem worldwide. In this study, a pot experiment using forest soils planted with the seedlings of four woody species was performed with weekly treatments of pH 4.40, 4.00, 3.52, and 3.05 simulated acid rain (SAR) for 42 months compared to a control of pH 5.00 lake water. The cumulative amounts of C and N mineralization in the five treated soils were determined after incubation at 25 ℃ for 65 d to examine the effects of SAR treatments.For all five treatments, cumulative CO2-C production ranged from 20.24 to 27.81 mg kg-1 dry soil, net production of available N from 17.37 to 48.95 mg kg-1 dry soil, and net production of NO-3-N from 9.09 to 46.23 mg kg-1 dry soil. SAR treatments generally enhanced the emission of CO2-C from the soils; however, SAR with pH 3.05 inhibited the emission.SAR treatments decreased the net production of available N and NO3-N. The cumulative CH4 and N2O productions from the soils increased with increasing amount of simulated acid rain. The cumulative CO2-C production and the net production of available N of the soil under Acmena acuminatissima were significantly higher (P≤0.05) than those under Schima superba and Cryptocarya concinna. The mineralization of soil organic C was related to the contents of soil organic C and N, but was not related to soil pH. However, the overall effect of acid rain on the storage of soil organic matter and the cycling of important nutrients depended on the amount of acid deposition and the types of forests.

  15. Long-term changes in structure and composition following hurricanes in a primary lower montane rain forest in Puerto Rico

    Science.gov (United States)

    P.L. Weaver

    2013-01-01

    Ridges within the lower montane rain forests (sensu Beard) of the Caribbean Basin are dominated by Dacryodes excelsa, a tree species known as tabonuco in Puerto Rico and gommier in the Lesser Antilles. Periodially, hurricanes traverse the islands causing changes in structure, species composition, and dynamics of forests. The chronology of post-hurricane vegetation...

  16. Threshold responses to soil moisture deficit by trees and soil in tropical rain forests: insights from field experiments

    Science.gov (United States)

    Patrick Meir; Tana Wood; David R. Galbraith; Paulo M. Brando; Antonio C.I. Da Costa; Lucy Rowland; Leandro V. Ferreira

    2015-01-01

    Many tropical rain forest regions are at risk of increased future drought. The net effects of drought on forest ecosystem functioning will be substantial if important ecological thresholds are passed. However, understanding and predicting these effects is challenging using observational studies alone. Field-based rainfall exclusion (canopy throughfall exclusion; TFE)...

  17. Bio-indicator species and Central African rain forest refuges in the Campo-Ma'an area, Cameroon

    NARCIS (Netherlands)

    Tchouto, M.G.P.; de Wilde, J.J.F.E.; de Boer, W.F.; van der Maesen, L.J.G.; Cleef, A.M.

    2009-01-01

    This study aims to examine the geographical position of late Pleistocene forest refuges in the tropical lowland rain forest in southern Cameroon by analysing the distribution of 178 selected bio-indicator species. We studied the distribution patterns of these species, such as strict and narrow

  18. A New Infrared Desert Dust Index over French Guyana Rain forest: First results

    Science.gov (United States)

    Molinie, J.; Barnacin, E.; Henry, J. L.; Gobinddass, M. L.; Panechou-Pulcherie, K.; Feuillard, T.; Nagau, J.

    2017-12-01

    Recently a NASA researcher showed the role of desert dust contribution for the Amazonian rain forest. In another hand, desert dust impact population health when PM 10 level reached values around and upper the PM 10 threshold of the 50 µg m-3, established by the World Health Organization (WHO). Infrared Desert Dust Index (IDDI) developed by Legrand with Meteosat infrared images, allow the following of desert dust plumes over semi-arid land. In French Guiana the WHO threshold is currently overpass in measurements done by ORA air quality network, in the two main towns located close to the coast. For inland population, it is very difficult to have continuous dust measures due to the low infrastructure supplies. We need to develop a tools in order to follow the crossing of desert dust over the French Guyana rain forest, from the coast to inland villages. Following the IDDI concept and comparing with VIIRS AOT EDR result over the same area, a modified IDDI for Amazonian region (IDDI_A) has been proposed to identify the dusty pixels over the forest. Despite of high cloud presence, a good correlation between AOT EDR and IDDI_A was obtained. The IDDI_A calculation has been applied over French Guiana area for different PM 10 level at Cayenne, a town along the coast.

  19. Evidence of late Palaeocene-early Eocene equatorial rain forest refugia in southern Western Ghats, India.

    Science.gov (United States)

    Prasad, V; Farooqui, A; Tripathi, S K M; Garg, R; Thakur, B

    2009-11-01

    Equatorial rain forests that maintain a balance between speciation and extinction are hot-spots for studies of biodiversity. Western Ghats in southern India have gained attention due to high tropical biodiversity and endemism in their southern most area. We attempted to track the affinities of the pollen fl ora of the endemic plants of Western Ghat area within the fossil palynoflora of late Palaeocene-early Eocene (approximately 55-50 Ma) sedimentary deposits of western and northeastern Indian region. The study shows striking similarity of extant pollen with twenty eight most common fossil pollen taxa of the early Palaeogene. Widespread occurrences of coal and lignite deposits during early Palaeogene provide evidence of existence of well diversified rain forest community and swampy vegetation in the coastal low lying areas all along the western and northeastern margins of the Indian subcontinent. Prevalence of excessive humid climate during this period has been seen as a result of equatorial positioning of Indian subcontinent, superimposed by a long term global warming phase (PETM and EECO) during the early Palaeogene. The study presents clear evidence that highly diversifi ed equatorial rain forest vegetation once widespread in the Indian subcontinent during early Palaeogene times, are now restricted in a small area as a refugia in the southernmost part of the Western Ghat area. High precipitation and shorter periods of dry months seem to have provided suitable environment to sustain lineages of ancient tropical vegetation in this area of Western Ghats in spite of dramatic climatic changes subsequent to the post India-Asia collision and during the Quaternary and Recent times.

  20. Diaspore bank of bryophytes in tropical rain forests: the importance of breeding system, phylum and microhabitat.

    Science.gov (United States)

    Maciel-Silva, Adaíses S; Válio, Ivany Ferraz Marques; Rydin, Håkan

    2012-02-01

    Diaspore banks are crucial for the maintenance and resilience of plant communities, but diaspore banks of bryophytes remain poorly known, especially from tropical ecosystems. This is the first study to focus on the role of diaspore banks of bryophytes in tropical rain forests. Our aim was to test whether microhabitat (substrate type) and species traits (breeding system, phylum) are important in explaining the diaspore bank composition. Using samples cultivated in the laboratory, we assessed the number of species and shoots emerging from bark, decaying wood and soil from two sites of the Atlantic rain forest (montane and sea level) in Brazil by comparing the contribution of species by phylum (mosses, liverworts) and breeding system (monoicous, dioicous). More species emerged from bark (68) and decaying wood (55) than from soil (22). Similar numbers of species were found at both sites. Mosses were more numerous in terms of number of species and shoots, and monoicous species dominated over dioicous species. Substrate pH had only weak effects on shoot emergence. Species commonly producing sporophytes and gemmae had a high contribution to the diaspore banks. These superficial diaspore banks represented the extant vegetation rather well, but held more monoicous species (probably short-lived species) compared to dioicous ones. We propose that diaspore bank dynamics are driven by species traits and microhabitat characteristics, and that short-term diaspore banks of bryophytes in tropical rain forests contribute to fast (re)establishment of species after disturbances and during succession, particularly dioicous mosses investing in asexual reproduction and monoicous mosses investing in sexual reproduction.

  1. Prevalence of pterygium and cataract in indigenous populations of the Brazilian Amazon rain forest.

    Science.gov (United States)

    Paula, J S; Thorn, F; Cruz, A A V

    2006-05-01

    To compare the prevalence of pterygium and cataract in four indigenous populations of the Brazilian Amazonian rain forest (Arawak, Tukano, Maku, and Yanomami) with different ethnic and social behaviour backgrounds. A cross-sectional pterygium and cataract survey was performed in 624 adult Indians of the Brazilian rain forest belonging to four different ethnic groups. The Indians were classified according to their social behaviour in two groups: Arawak and Tukano (group 1) and Maku and Yanomami (group 2). Slit-lamp biomicroscopy was employed to examine the entire sample. All subjects were classified as 1 or 0 according to the presence or absence pterygium and cataract. Sex and age were also recorded. chi(2)-tests revealed that the prevalence of pterygium and cataract differed significantly between groups 1 and 2. For pterygia: 36.6% (97/265) and 5.0% (18/359), respectively (chi(2)=101.2, P<0.0001), and for cataracts: 24.5% (65/265) and 13.7% (49/359) respectively (chi(2)=12.09, P=0.0005). Gender was not associated with pterygium (P=0.1326) and cataract (P=0.2263) in both groups. Elderly subjects showed a significantly higher prevalence of cataract (P<0.0001). The prevalence of pterygia did not increase with age (P=0.8079) in both groups. Indians of group 1 have higher prevalence of pterygia and cataract than Indians of group 2. Social behaviour, especially the rate of sun exposure, appears to be the main factor for the different rates of pterygium and cataract displayed by these indigenous people of the Brazilian rain forest.

  2. Large-Scale Mapping of Tree-Community Composition as a Surrogate of Forest Degradation in Bornean Tropical Rain Forests

    Directory of Open Access Journals (Sweden)

    Shogoro Fujiki

    2016-12-01

    Full Text Available Assessment of the progress of the Aichi Biodiversity Targets set by the Convention on Biological Diversity (CBD and the safeguarding of ecosystems from the perverse negative impacts caused by Reducing Emissions from Deforestation and Forest Degradation Plus (REDD+ requires the development of spatiotemporally robust and sensitive indicators of biodiversity and ecosystem health. Recently, it has been proposed that tree-community composition based on count-plot surveys could serve as a robust, sensitive, and cost-effective indicator for forest intactness in Bornean logged-over rain forests. In this study, we developed an algorithm to map tree-community composition across the entire landscape based on Landsat imagery. We targeted six forest management units (FMUs, each of which ranged from 50,000 to 100,000 ha in area, covering a broad geographic range spanning the most area of Borneo. Approximately fifty 20 m-radius circular plots were established in each FMU, and the differences in tree-community composition at a genus level among plots were examined for trees with diameter at breast height ≥10 cm using an ordination with non-metric multidimensional scaling (nMDS. Subsequently, we developed a linear regression model based on Landsat metrics (e.g., reflectance value, vegetation indices and textures to explain the nMDS axis-1 scores of the plots, and extrapolated the model to the landscape to establish a tree-community composition map in each FMU. The adjusted R2 values based on a cross-validation approach between the predicted and observed nMDS axis-1 scores indicated a close correlation, ranging from 0.54 to 0.69. Histograms of the frequency distributions of extrapolated nMDS axis-1 scores were derived from each map and used to quantitatively diagnose the forest intactness of the FMUs. Our study indicated that tree-community composition, which was reported as a robust indicator of forest intactness, could be mapped at a landscape level to

  3. The orchid-bee faunas (Hymenoptera: Apidae of two Atlantic Forest remnants in southern Bahia, eastern Brazil

    Directory of Open Access Journals (Sweden)

    A Nemésio

    Full Text Available The orchid-bee faunas of the ‘Parque Nacional do Pau Brasil’ (8,500 ha and ‘RPPN Estação Veracel’ (6,000 ha, two Atlantic Forest remnants in the southern state of Bahia, northeastern Brazil, were surveyed. Seventeen chemical compounds were used as scent baits to attract orchid-bee males. Seven hundred and twelve males belonging to 20 species were actively collected with insect nets during 80 hours in February and April, 2009. Euglossa marianae Nemésio, 2011, the most sensitive orchid-bee species of the Atlantic Forest, was recorded at both preserves, though in low abundance. ‘RPPN Estação Veracel’ is the smallest forest patch where Euglossa marianae has ever been recorded.

  4. First direct landscape-scale measurement of tropical rain forest Leaf Area Index, a key driver of global primary productivity

    Science.gov (United States)

    David B. Clark; Paulo C. Olivas; Steven F. Oberbauer; Deborah A. Clark; Michael G. Ryan

    2008-01-01

    Leaf Area Index (leaf area per unit ground area, LAI) is a key driver of forest productivity but has never previously been measured directly at the landscape scale in tropical rain forest (TRF). We used a modular tower and stratified random sampling to harvest all foliage from forest floor to canopy top in 55 vertical transects (4.6 m2) across 500 ha of old growth in...

  5. Nutrient additions to a tropical rain forest drive substantial soil carbon dioxide losses to the atmosphere.

    Science.gov (United States)

    Cleveland, Cory C; Townsend, Alan R

    2006-07-05

    Terrestrial biosphere-atmosphere carbon dioxide (CO(2)) exchange is dominated by tropical forests, where photosynthetic carbon (C) uptake is thought to be phosphorus (P)-limited. In P-poor tropical forests, P may also limit organic matter decomposition and soil C losses. We conducted a field-fertilization experiment to show that P fertilization stimulates soil respiration in a lowland tropical rain forest in Costa Rica. In the early wet season, when soluble organic matter inputs to soil are high, P fertilization drove large increases in soil respiration. Although the P-stimulated increase in soil respiration was largely confined to the dry-to-wet season transition, the seasonal increase was sufficient to drive an 18% annual increase in CO(2) efflux from the P-fertilized plots. Nitrogen (N) fertilization caused similar responses, and the net increases in soil respiration in response to the additions of N and P approached annual soil C fluxes in mid-latitude forests. Human activities are altering natural patterns of tropical soil N and P availability by land conversion and enhanced atmospheric deposition. Although our data suggest that the mechanisms driving the observed respiratory responses to increased N and P may be different, the large CO(2) losses stimulated by N and P fertilization suggest that knowledge of such patterns and their effects on soil CO(2) efflux is critical for understanding the role of tropical forests in a rapidly changing global C cycle.

  6. Ecology and silvicultural management for the rehabilitation in rain forests of low altitude on complex metamorphic

    Directory of Open Access Journals (Sweden)

    Gonzalo Cantos Cevallos

    2018-01-01

    Full Text Available In order to characterize ecology and silvicultural management for the rehabilitation of the low altitude rain forest on a metamorphic complex, Quibiján-Naranjal del Toa sector, a floristic inventory was carried out, 36 sample plots of 20 x 25 m in the forest in both sides of Toa's riverside. Tree species with d1,3 e» 5 cm were measured, a total of 1507 individuals represented in 52 species belonging to 49 genera and 24 families were identified and evaluated. Both forests were statistically compared in terms of richness, composition, structure, diversity and abundance, with a high alpha and beta diversity. The species with the highest value index of ecological importance were determined. The families Fabaceae, Moraceae, Lauraceae and Meliaceae are the most representative in terms of species and genera. The most important species are Hibiscus elatus, Calophyllum utile, Carapa guianensis, Buhenavia capitata, y Guarea guara, among others, which stand out as the most abundant. Economic occupation was adequate in a few plots and incomplete in most of the sampling units. Taking into account the results obtained, we propose silvicultural actions aimed at sustainable forest management through the application of improvement shorts and the method of enrichment in dense spaced-groups for the rehabilitation and the achievement of the expected multiethane forest.

  7. Seed rain dynamics following disturbance exclusion in a secondary tropical dry forest in Morelos, Mexico.

    Science.gov (United States)

    Ceccon, Eliane; Hernández, Patricia

    2009-01-01

    In most of the legally protected areas in Mexico local inhabitants use natural resources, such as fire wood or cattle grazing. These frequent but low-intensity disturbances have consequences at various levels of the tropical ecosystems and strongly impact forest structure and its regeneration capacity. Despite their importance, the effects of these perturbations in many aspects of tropical forest ecology and in the forest's capacity to recover after disturbance exclusion remain poorly understood. Understanding the impact of these processes on tropical forests is necessary for rehabilitating these forests and enhancing their productivity. In this study, we evaluate the impact of twelve years of exclusion (E) of cattle grazing and fire wood extraction in the composition and dynamics of seed rain, and compare this assessment to a similar analysis in an area where these perturbations continued (without exclusion, WE). We found a strong seasonality in seed rain (96% of seeds fell in the dry season) in both areas. There were no significant differences between E and WE sites in relation to overall seed density, species richness and diversity. However, the distribution along the year of seed species density was significantly different among the E and WE sites. The Jaccard's similarity index between E and WE sites was relatively low (0.57). Barochory was the most common dispersal mode observed among the 23 species in terms of seed species density (48%), followed by anemochory (39%) and zoochory (13%). In relation to seed density, anemochory was the most frequent dispersal mode (88%). Most species in the zone were categorized as small seeds (92%), and there were no significant differences in the distribution of seed size between E and WE. The spatial pattern of dispersal of the four species with the highest relative importance value index, in both areas, was aggregated. Twelve years of disturbance exclusion were not enough to fully restore the seed rain of the area; some

  8. Mapping and monitoring forest remnants : a multiscale analysis of spatio-temporal data

    NARCIS (Netherlands)

    Carvalho, de L.M.T.

    2001-01-01

    KEYWORDS : Landsat, time series, machine learning, semideciduous Atlantic forest, Brazil, wavelet transforms, classification, change detection

    Forests play a major role in important global matters such as carbon cycle, climate change, and biodiversity. Besides, forests also

  9. Forest edge disturbance increases rattan abundance in tropical rain forest fragments.

    Science.gov (United States)

    Campbell, Mason J; Edwards, Will; Magrach, Ainhoa; Laurance, Susan G; Alamgir, Mohammed; Porolak, Gabriel; Laurance, William F

    2017-07-20

    Human-induced forest fragmentation poses one of the largest threats to global diversity yet its impact on rattans (climbing palms) has remained virtually unexplored. Rattan is arguably the world's most valuable non-timber forest product though current levels of harvesting and land-use change place wild populations at risk. To assess rattan response to fragmentation exclusive of harvesting impacts we examined rattan abundance, demography and ecology within the forests of northeastern, Australia. We assessed the community abundance of rattans, and component adult (>3 m) and juvenile (≤3 m) abundance in five intact forests and five fragments (23-58 ha) to determine their response to a range of environmental and ecological parameters. Fragmented forests supported higher abundances of rattans than intact forests. Fragment size and edge degradation significantly increased adult rattan abundance, with more in smaller fragments and near edges. Our findings suggest that rattan increase within fragments is due to canopy disturbance of forest edges resulting in preferential, high-light habitat. However, adult and juvenile rattans may respond inconsistently to fragmentation. In managed forest fragments, a rattan abundance increase may provide economic benefits through sustainable harvesting practices. However, rattan increases in protected area forest fragments could negatively impact conservation outcomes.

  10. Off-nadir antenna bias correction using Amazon rain forest sigma deg data. [Brazil

    Science.gov (United States)

    Birrer, I. J.; Bracalente, E. M.; Dome, G. J.; Sweet, J.; Berthold, G.; Moore, R. K. (Principal Investigator)

    1981-01-01

    The radar response from the Amazon rain forest was studied to determine the suitability of this region for use as a standard target to calibrate a scatterometer like that proposed for the National Ocean Satellite System (NOSS). Backscattering observations made by the SEASAT-1 scatterometer system show the Amazon rain forest to be a homogeneous, azimuthally-isotropic, radar target which is insensitive to polarization. The variation with angle of incidence may be adequately modeled as sigma deg (dB) = alpha theta + beta with typical values for the incidence-angle coefficient from 0.07 dB deg to 0.15 dB/deg. A small diurnal effect occurs, with measurements at sunrise being 0.5 dB to 1 dB higher than the rest of the day. Maximum likelihood estimation algorithms are presented which permit determination of relative bias and true pointing angle for each beam. Specific implementation of these algorithms for the proposed NOSS scatterometer system is also discussed.

  11. Assessment of organochlorine pesticide residues in Atlantic Rain Forest fragments, Rio de Janeiro, Brazil

    Energy Technology Data Exchange (ETDEWEB)

    Soares Quinete, Natalia, E-mail: nataliaquinete@yahoo.com.br [Instituto Nacional de Tecnologia, Departamento de Quimica Analitica, Laboratorio de Quimica Analitica e Metrologia em Quimica, Av. Venezuela, 82 - Rio de Janeiro, RJ 20081-312 (Brazil); Santos de Oliveira, Elba dos [Instituto Nacional de Tecnologia, Departamento de Energia, Av. Venezuela, 82 - Rio de Janeiro, RJ 20081-312 (Brazil); Fernandes, Daniella R. [Universidade Federal do Rio de Janeiro, Instituto de Quimica, Departamento de Quimica Analitica, CT - Bloco A, Cidade Universitaria, 21941-909 - Rio de Janeiro (Brazil); Souza Avelar, Andre de [Universidade Federal do Rio de Janeiro, Departamento de Geografia, Instituto de Geociencias, CCMN, Bloco F, Cidade Universitaria, 21941-919 - Rio de Janeiro (Brazil); Erthal Santelli, Ricardo [Universidade Federal do Rio de Janeiro, Instituto de Quimica, Departamento de Quimica Analitica, CT - Bloco A, Cidade Universitaria, 21941-909 - Rio de Janeiro (Brazil)

    2011-12-15

    A superficial water quality survey in a watershed of the Paraiba do Sul River, the main water supply for the most populated cities of southeastern Brazil, was held in order to assess the impact of the expansion of agricultural activity in the near border of the Atlantic Rain Forest. The aim of this study was to investigate the presence of priority organochlorine pollutants in soils and superficial waters of Atlantic rainforest fragments in Teresopolis, Rio de Janeiro State. Soil sample preparations were compared by using ultrasound, microwave assisted extraction and Soxhlet extraction. Recoveries of matrix spiked samples ranged from 70 to 130%. Analysis of a certified soil material showed recoveries ranging from 71 to 234%. Although low concentrations of organochlorine residues were found in water and soil samples, this area is of environmental importance and concern, thus demanding a monitoring program of its compartments. - Highlights: > The organochlorine pollutants occurrence in the Atlantic Rain Forest was investigated. > PARNASO was considered a control area of environmental quality. > Extractions methods were compared for typical C-rich soils samples from Brazil. > Low concentrations of organochlorine residues were found in water and soil samples. > A monitoring program is demanded due to the environmental importance of the area. - The occurrence of organochlorine pollutants in soils of the Atlantic rainforest fragments in Rio de Janeiro, Brazil demands a monitoring program of its compartments.

  12. Assessment of organochlorine pesticide residues in Atlantic Rain Forest fragments, Rio de Janeiro, Brazil

    International Nuclear Information System (INIS)

    Soares Quinete, Natalia; Santos de Oliveira, Elba dos; Fernandes, Daniella R.; Souza Avelar, Andre de; Erthal Santelli, Ricardo

    2011-01-01

    A superficial water quality survey in a watershed of the Paraiba do Sul River, the main water supply for the most populated cities of southeastern Brazil, was held in order to assess the impact of the expansion of agricultural activity in the near border of the Atlantic Rain Forest. The aim of this study was to investigate the presence of priority organochlorine pollutants in soils and superficial waters of Atlantic rainforest fragments in Teresopolis, Rio de Janeiro State. Soil sample preparations were compared by using ultrasound, microwave assisted extraction and Soxhlet extraction. Recoveries of matrix spiked samples ranged from 70 to 130%. Analysis of a certified soil material showed recoveries ranging from 71 to 234%. Although low concentrations of organochlorine residues were found in water and soil samples, this area is of environmental importance and concern, thus demanding a monitoring program of its compartments. - Highlights: → The organochlorine pollutants occurrence in the Atlantic Rain Forest was investigated. → PARNASO was considered a control area of environmental quality. → Extractions methods were compared for typical C-rich soils samples from Brazil. → Low concentrations of organochlorine residues were found in water and soil samples. → A monitoring program is demanded due to the environmental importance of the area. - The occurrence of organochlorine pollutants in soils of the Atlantic rainforest fragments in Rio de Janeiro, Brazil demands a monitoring program of its compartments.

  13. Current and Future Carbon Budgets of Tropical Rain Forest: A Cross Scale Analysis. Final Report

    Energy Technology Data Exchange (ETDEWEB)

    Oberbauer, S. F.

    2004-01-16

    The goal of this project was to make a first assessment of the major carbon stocks and fluxes and their climatic determinants in a lowland neotropical rain forest, the La Selva Biological Station, Costa Rica. Our research design was based on the concurrent use of several of the best available approaches, so that data could be cross-validated. A major focus of our effort was to combine meteorological studies of whole-forest carbon exchange (eddy flux), with parallel independent measurements of key components of the forest carbon budget. The eddy flux system operated from February 1998 to February 2001. To obtain field data that could be scaled up to the landscape level, we monitored carbon stocks, net primary productivity components including tree growth and mortality, litterfall, woody debris production, root biomass, and soil respiration in a series of replicated plots stratified across the major environmental gradients of the forest. A second major focus of this project was on the stocks and changes of carbon in the soil. We used isotope studies and intensive monitoring to investigate soil organic stocks and the climate-driven variation of soil respiration down the soil profile, in a set of six 4m deep soil shafts stratified across the landscape. We measured short term tree growth, climate responses of sap flow, and phenology in a suite of ten canopy trees to develop individual models of tree growth to daytime weather variables.

  14. Nitrogen and phosphorus resorption in a neotropical rain forest of a nutrient-rich soil.

    Science.gov (United States)

    Martínez-Sánchez, José Luis

    2005-01-01

    In tropical forests with nutrient-rich soil tree's nutrient resorption from senesced leaves has not always been observed to be low. Perhaps this lack of consistence is partly owing to the nutrient resorption methods used. The aim of the study was to analyse N and P resorption proficiency from tropical rain forest trees in a nutrient-rich soil. It was hypothesised that trees would exhibit low nutrient resorption in a nutrient-rich soil. The soil concentrations of total N and extractable P, among other physical and chemical characteristics, were analysed in 30 samples in the soil surface (10 cm) of three undisturbed forest plots at 'Estaci6n de Biologia Los Tuxtlas' on the east coast of Mexico (18 degrees 34' - 18 degrees 36' N, 95 degrees 04' - 95 degrees 09' W). N and P resorption proficiency were determined from senescing leaves in 11 dominant tree 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. Soil was rich in total N (0.50%, n = 30) and extractable P (4.11 microg g(-1) n = 30). As expected, trees showed incomplete N (1.13%, n = 11) and P (0.11%, n = 1) resorption. With a more accurate method of nutrient resorption assessment, it is possible to prove that a forest community with a nutrient-rich soil can have low levels of N and P resorption.

  15. Biomass Burning:Significant Source of Nitrate and Sulfate for the Andean Rain Forest in Ecuador

    Science.gov (United States)

    Fabian, P.; Rollenbeck, R.; Spichtinger, N.

    2009-04-01

    Forest fires are significant sources of carbon, sulfur and nitrogen compounds which, along with their photochemically generated reaction products, can be transported over very long distances, even traversing oceans. Chemical analyses of rain and fogwater samples collected on the wet eastern slopes of the Ecuadorian Andes show frequent episodes of high sulfate and nitrate concentration, from which annual deposition rates of about14 kg/ha and 7 kg/ha ,respectively, are derived. These are comparable to those observed in polluted central Europe. Regular rain and fogwater sampling along an altitude profile between 1800 and 3185 m, has been carried out since 2002.The research area located at 30 58'S ,790 5' W is dominated by trade winds from easterly directions. The samples, generally accumulated over 1-week intervals, were analysed for pH, conductivity and major ions(K+,Na+,NH4+,Ca2+,Mg 2+,SO42-,NO3-,PO43-).For all components a strong seasonal variation is observed, while the altitudinal gradient is less pronounced. About 65 % of the weekly samples were significantly loaded with cations and anions, with pH often as low 3.5 to 4.0 and conductivity up to 50 uS/cm. Back trajectories (FLEXTRA) showed that respective air masses had passed over areas of intense biomass burning, sometimes influenced by volcanoes, ocean spray, or even episodic Sahara and/or Namib desert dust interference not discussed here. Enhanced SO4 2-and NO3- were identified, by combining satellite-based fire pixels with back trajectories, as predominantly resulting from biomass burning. For most cases, by using emission inventories, anthropogenic precursor sources other than forest fires play a minor role, thus leaving biomass burning as the main source of nitrate and sulphate in rain and fogwater. Some SO4 2- , about 10 % of the total input, could be identified to originate from active volcanoes, whose plumes were sometimes encountered by the respective back trajectories. While volcanic, oceanic and

  16. Semi-deciduous forest remnants in Benin: patterns and floristic characterisation

    NARCIS (Netherlands)

    Adomou, A.C.; Akoegninou, A.; Sinsin, B.; Foucault, de B.; Maesen, van der L.J.G.

    2009-01-01

    Patterns of semi-deciduous forest are investigated in Benin by means of phytosociological releves and multivariate analyses Species and family importance values are assessed for each forest type The classifications and DCA ordination of 176 semi-deciduous forest releves result in six forest types,

  17. Characterizing the phylogenetic tree community structure of a protected tropical rain forest area in Cameroon.

    Science.gov (United States)

    Manel, Stéphanie; Couvreur, Thomas L P; Munoz, François; Couteron, Pierre; Hardy, Olivier J; Sonké, Bonaventure

    2014-01-01

    Tropical rain forests, the richest terrestrial ecosystems in biodiversity on Earth are highly threatened by global changes. This paper aims to infer the mechanisms governing species tree assemblages by characterizing the phylogenetic structure of a tropical rain forest in a protected area of the Congo Basin, the Dja Faunal Reserve (Cameroon). We re-analyzed a dataset of 11538 individuals belonging to 372 taxa found along nine transects spanning five habitat types. We generated a dated phylogenetic tree including all sampled taxa to partition the phylogenetic diversity of the nine transects into alpha and beta components at the level of the transects and of the habitat types. The variation in phylogenetic composition among transects did not deviate from a random pattern at the scale of the Dja Faunal Reserve, probably due to a common history and weak environmental variation across the park. This lack of phylogenetic structure combined with an isolation-by-distance pattern of taxonomic diversity suggests that neutral dispersal limitation is a major driver of community assembly in the Dja. To assess any lack of sensitivity to the variation in habitat types, we restricted the analyses of transects to the terra firme primary forest and found results consistent with those of the whole dataset at the level of the transects. Additionally to previous analyses, we detected a weak but significant phylogenetic turnover among habitat types, suggesting that species sort in varying environments, even though it is not predominating on the overall phylogenetic structure. Finer analyses of clades indicated a signal of clustering for species from the Annonaceae family, while species from the Apocynaceae family indicated overdispersion. These results can contribute to the conservation of the park by improving our understanding of the processes dictating community assembly in these hyperdiverse but threatened regions of the world.

  18. Characterizing the Phylogenetic Tree Community Structure of a Protected Tropical Rain Forest Area in Cameroon

    Science.gov (United States)

    Munoz, François; Couteron, Pierre; Hardy, Olivier J.; Sonké, Bonaventure

    2014-01-01

    Tropical rain forests, the richest terrestrial ecosystems in biodiversity on Earth are highly threatened by global changes. This paper aims to infer the mechanisms governing species tree assemblages by characterizing the phylogenetic structure of a tropical rain forest in a protected area of the Congo Basin, the Dja Faunal Reserve (Cameroon). We re-analyzed a dataset of 11538 individuals belonging to 372 taxa found along nine transects spanning five habitat types. We generated a dated phylogenetic tree including all sampled taxa to partition the phylogenetic diversity of the nine transects into alpha and beta components at the level of the transects and of the habitat types. The variation in phylogenetic composition among transects did not deviate from a random pattern at the scale of the Dja Faunal Reserve, probably due to a common history and weak environmental variation across the park. This lack of phylogenetic structure combined with an isolation-by-distance pattern of taxonomic diversity suggests that neutral dispersal limitation is a major driver of community assembly in the Dja. To assess any lack of sensitivity to the variation in habitat types, we restricted the analyses of transects to the terra firme primary forest and found results consistent with those of the whole dataset at the level of the transects. Additionally to previous analyses, we detected a weak but significant phylogenetic turnover among habitat types, suggesting that species sort in varying environments, even though it is not predominating on the overall phylogenetic structure. Finer analyses of clades indicated a signal of clustering for species from the Annonaceae family, while species from the Apocynaceae family indicated overdispersion. These results can contribute to the conservation of the park by improving our understanding of the processes dictating community assembly in these hyperdiverse but threatened regions of the world. PMID:24936786

  19. Epiphytic ferns in swamp forest remnants of the coastal plain of southern Brazil: latitudinal effects on the plant community

    Directory of Open Access Journals (Sweden)

    Letícia S. Machado

    Full Text Available ABSTRACT Community structure and spatial distribution of epiphytic ferns in swamp forest remnants along the coastal plain of the state of Rio Grande do Sul were analyzed. A total of 440 trees were sampled in fifty-seven 10 x 10 m plots. Each phorophyte was divided into five ecological zones (strata, where all species of epiphytic ferns were recorded. A total of 34 species representing 18 genera in six families were recorded. Polypodiaceae was the most represented family with 17 species, and Microgramma vacciniifolia had the highest epiphytic importance value. Characteristic holoepiphyte was the predominant ecological category, representing 70 % of the species. Ordination analysis showed a gradual change in floristic composition between ecological zones with richness differing significantly between strata. We observed that with increasing latitude there was a decrease in mean temperature and total rainfall, but an increase in frosts. These climatic and phytogeography changes result in a reduction in species richness and a change in the structure of epiphytic fern communities in a north-to-south direction. The importance of swamp forest remnants of the coastal plain to the diversity of epiphytic ferns is discussed.

  20. Sand fly population dynamics and cutaneous leishmaniasis among soldiers in an Atlantic forest remnant in northeastern Brazil.

    Science.gov (United States)

    Dantas-Torres, Filipe; Sales, Kamila Gaudêncio da Silva; Miranda, Débora Elienai de Oliveira; da Silva, Fernando José; Figueredo, Luciana Aguiar; de Melo, Fábio Lopes; de Brito, Maria Edileuza Felinto; Andrade, Maria Sandra; Brandão-Filho, Sinval Pinto

    2017-02-01

    Outbreaks of cutaneous leishmaniasis are relatively common among soldiers involved in nocturnal activities in tropical forests. We investigated the population dynamics of sand flies in a military training camp located in a remnant of Atlantic rainforest in northeastern Brazil, where outbreaks of cutaneous leishmaniasis have sporadically been described. From July 2012 to July 2014, light traps were monthly placed in 10 collection sites, being nine sites located near the forest edge and one near a sheep and goat stable. Light traps operated from 5:00 pm to 6:00 am, during four consecutive nights. Leishmania infection in sand flies was assessed using a fast real-time PCR assay. Cases of cutaneous leishmaniasis among soldiers were also investigated. In total, 24,606 sand flies belonging to 25 species were identified. Males (n = 12,683) predominated over females (n = 11,923). Sand flies were present during all months, being more numerous in March (n = 1,691) and April 2013 (n = 3,324). Lutzomyia choti (72.9%) was the most abundant species, followed by Lutzomyia longispina (13.8%), Lutzomyia complexa (5.3%), representing together >90% of the sand flies collected. Forty cases of cutaneous leishmaniasis were recorded among soldiers from January 2012 to December 2014. Leishmania isolates were obtained from eight patients and were all characterized as Leishmania braziliensis. Soldiers and anyone overnighting in Atlantic rainforest remnants should adopt preventative measures such as the use of repellents on bare skin or clothes and insecticide-treated tents.

  1. Palynological record of tropical rain forest vegetation and sea level fluctuations since 140 ka from sediment core, south-eastern Arabian sea.

    Digital Repository Service at National Institute of Oceanography (India)

    Farooqui, A.; Pattan, J.N.; Parthiban, G.; Srivastava, J.; Ranjana

    of rain forest “plant refugia” on land. Neogene rain forest flora recorded earlier from the Varkala Formation and the present record of its existence since MIS-6 in the region provide an understanding that the monsoon circulation over southern India...

  2. Variation in wood anatomy of species with a distribution covering both rain forest and savanna areas of the Ivory Coast, West-Africa

    NARCIS (Netherlands)

    Outer, den R.W.; Veenendaal, van W.L.H.

    1976-01-01

    The variation in wood anatomy within 30 hardwood species, each with a distribution covering both rain forest and savanna areas of the Ivory Coast, Africa, has been studied. Compared to specimens from the rain forest, material from the savanna tends to have more wood ray tissue (rays are higher,

  3. Diameter Growth of Juvenile Trees after Gap Formation in a Bolivian Rain Forest: Responses are Strongly Species-specific and Size-dependent.

    NARCIS (Netherlands)

    Soliz-Gamboa, C.C.; Sandbrink, A.; Zuidema, P.A.

    2012-01-01

    We evaluated growth responses to gap formation for juvenile individuals of three canopy rain forest species: Peltogyne cf. heterophylla, Clarisia racemosa and Cedrelinga catenaeformis. Gaps were formed during selective logging operations 7 yr before sampling in a Bolivian rain forest. We collected

  4. On the potential of long wavelength imaging radars for mapping vegetation types and woody biomass in tropical rain forests

    Science.gov (United States)

    Rignot, Eric J.; Zimmermann, Reiner; Oren, Ram

    1995-01-01

    In the tropical rain forests of Manu, in Peru, where forest biomass ranges from 4 kg/sq m in young forest succession up to 100 kg/sq m in old, undisturbed floodplain stands, the P-band polarimetric radar data gathered in June of 1993 by the AIRSAR (Airborne Synthetic Aperture Radar) instrument separate most major vegetation formations and also perform better than expected in estimating woody biomass. The worldwide need for large scale, updated biomass estimates, achieved with a uniformly applied method, as well as reliable maps of land cover, justifies a more in-depth exploration of long wavelength imaging radar applications for tropical forests inventories.

  5. Tree fern trunks facilitate seedling regeneration in a productive lowland temperate rain forest.

    Science.gov (United States)

    Gaxiola, Aurora; Burrows, Larry E; Coomes, David A

    2008-03-01

    Seedling regeneration on forest floors is often impaired by competition with established plants. In some lowland temperate rain forests, tree fern trunks provide safe sites on which tree species establish, and grow large enough to take root in the ground and persist. Here we explore the competitive and facilitative effects of two tree fern species, Cyathea smithii and Dicksonia squarrosa, on the epiphytic regeneration of tree species in nutrient-rich alluvial forests in New Zealand. The difficulties that seedlings have in establishing on vertical tree fern trunks were indicated by the following observations. First, seedling abundance was greatest on the oldest sections of tree fern trunks, near the base, suggesting that trunks gradually recruited more and more seedlings over time, but many sections of trunk were devoid of seedlings, indicating the difficulty of establishment on a vertical surface. Second, most seedlings were from small-seeded species, presumably because smaller seeds can easily lodge on tree fern trunks. Deer browsing damage was observed on 73% of epiphytic seedlings growing within 2 m of the ground, whereas few seedlings above that height were browsed. This suggests that tree ferns provide refugia from introduced deer, and may slow the decline in population size of deer-preferred species. We reasoned that tree ferns would compete with epiphytic seedlings for light, because below the tree fern canopy photosynthetically active radiation (PAR) was about 1% of above-canopy PAR. Frond removal almost tripled %PAR on the forest floor, leading to a significant increase in the height growth rate (HGR) of seedlings planted on the forest floor, but having no effects on the HGRs of epiphytic seedlings. Our study shows evidence of direct facilitative interactions by tree ferns during seedling establishment in plant communities associated with nutrient-rich soils.

  6. Long-term Seedling Dynamics of Tree Species in a Subtropical Rain Forest, Taiwan

    Directory of Open Access Journals (Sweden)

    Chia-Hao Chang-Yang

    2013-03-01

    Full Text Available Knowledge of demographical rates at seedling stage is critical for understanding forest composition and dynamics. We monitored the seedling dynamics of tree species in a subtropical rain forest in Fushan, northern Taiwan (24°45’ N, 121°35’ E during an 8-yr period (2003–2010. There were great temporal fluctuations in the seedling density, which might be largely driven by the pulses of seedling recruitment. Interspecific variation in the seedling abundance, however, was not related to the reproductive adult abundance. Previous studies showed that frequent typhoon disturbances contributed to the high canopy openness and high understory light availability at Fushan, which might benefit tree regeneration. But our results do not support this idea. Most of the newly recruited seedlings died within six months and only grew 1.55 ± 0.20 cm per year, which might be suppressed by the dense understory vegetation. Our results suggested that the majority of tree species in Fushan were recruitment limited, which might have important consequences for species coexistence. High temporal variability in recruitment density and low growth rates of seedlings emphasize the importance of long-term studies to our understandings of forest dynamics.

  7. Gap Dynamics and Structure of Two Old-Growth Beech Forest Remnants in Slovenia

    Science.gov (United States)

    Rugani, Tihomir; Diaci, Jurij; Hladnik, David

    2013-01-01

    Context Due to a long history of intensive forest exploitation, few European beech (Fagus sylvatica L.) old-growth forests have been preserved in Europe. Material and Methods We studied two beech forest reserves in southern Slovenia. We examined the structural characteristics of the two forest reserves based on data from sample plots and complete inventory obtained from four previous forest management plans. To gain a better understanding of disturbance dynamics, we used aerial imagery to study the characteristics of canopy gaps over an 11-year period in the Kopa forest reserve and a 20-year period in the Gorjanci forest reserve. Results The results suggest that these forests are structurally heterogeneous over small spatial scales. Gap size analysis showed that gaps smaller than 500 m2 are the dominant driving force of stand development. The percentage of forest area in canopy gaps ranged from 3.2 to 4.5% in the Kopa forest reserve and from 9.1 to 10.6% in the Gorjanci forest reserve. These forests exhibit relatively high annual rates of coverage by newly established (0.15 and 0.25%) and closed (0.08 and 0.16%) canopy gaps. New gap formation is dependant on senescent trees located throughout the reserve. Conclusion We conclude that these stands are not even-sized, but rather unevenly structured. This is due to the fact that the disturbance regime is characterized by low intensity, small-scale disturbances. PMID:23308115

  8. Technique of uranium exploration in tropical rain forests as applied in Sumatra and other tropical areas

    International Nuclear Information System (INIS)

    Hahn, L.

    1983-01-01

    The technique of uranium prospecting in areas covered by tropical rain forest is discussed using a uranium exploration campaign conducted from 1976 to 1978 in Western Sumatra as an example. A regional reconnaissance survey using stream sediment samples combined with radiometric field measurements proved ideal for covering very large areas. A mobile field laboratory was used for the geochemical survey. Helicopter support in diffult terrain was found to be very efficient and economical. A field procedure for detecting low uranium concentrations in stream water samples is described. This method has been successfully applied in Sarawak. To distinguish meaningful uranium anomalies in water from those with no meaning for prospecting, the correlations between U content and conductivity of the water and between U content and Ca and HCO 3 content must be considered. This method has been used successfully in a geochemical survey in Thailand. (author)

  9. Ion fluxes from fog and rain to an agricultural and a forest ecosystem in Europe

    Science.gov (United States)

    Thalmann, E.; Burkard, R.; Wrzesinsky, T.; Eugster, W.; Klemm, O.

    The deposition fluxes of inorganic compounds dissolved in fog and rain were quantified for two different ecosystems in Europe. The fogwater deposition fluxes were measured by employing the eddy covariance method. The site in Switzerland that lies within an agricultural area surrounded by the Jura mountains and the Alps is often exposed to radiation fog. At the German mountain forest ecosystem, on the other hand, advection fog occurs most frequently. At the Swiss site, fogwater deposition fluxes of the dominant components SO 42- (0.027 mg S m -2 day -1), NO 3- (0.030 mg N m -2 day -1) and NH 4+ (0.060 mg N m -2 day -1) were estimated to be fogwater concentrations of all major ions if air originated from the east (i.e. the Czech Republic), which is in close agreement with earlier studies.

  10. Multiple antibiotic resistant Escherichia coli from a tropical rain forest stream

    Energy Technology Data Exchange (ETDEWEB)

    Carrasco, C.E.; Alvarez, H.J.; Ortiz, N.; Bisbal, M.; Arias, W.; Baerga, C. [Univ. of Puerto Rico, Rio Piedras (Puerto Rico). Dept. of Biology; Hazen, T.C. [E.I. DuPont de Nemours and Co., Aiken, SC (United States). Savannah River Lab.

    1988-12-31

    High densities of fecal coliforms were obtained from a pristine site and sewage contaminated site in a tropical rain forest watershed in Puerto Rico. Confirmation of fecal coliform isolates as Escherichia coli was significantly lower than for temperate waters. Antibiotic resistance and multiple antibiotic resistance were common for isolates at both sites; however, the site receiving sewage effluent had a greater proportion of multiple antibiotic resistant isolates. R. plasmids were recovered from 4 MAR isolates, 2 from each site. All recovered plasmids were approximately 1 kilobase. The recovered plasmid were also capable of transforming E. coli HB101 in vitro. The high concentrations of enterobacteriaceae, small R-plasmid size, R-plasmid transformability, and long term survival of fecal origin bacteria in tropical freshwater environments give increasing importance to adequate sewage treatment, and better indicator monitoring methods for tropical areas.

  11. Degradation of Root Community Traits as Indicator for Transformation of Tropical Lowland Rain Forests into Oil Palm and Rubber Plantations.

    Science.gov (United States)

    Sahner, Josephine; Budi, Sri Wilarso; Barus, Henry; Edy, Nur; Meyer, Marike; Corre, Marife D; Polle, Andrea

    2015-01-01

    Conversion of tropical forests into intensely managed plantations is a threat to ecosystem functions. On Sumatra, Indonesia, oil palm (Elaeis guineensis) plantations are rapidly expanding, displacing rain forests and extensively used rubber (Hevea brasiliensis) agro-forests. Here, we tested the influence of land use systems on root traits including chemical traits (carbon, nitrogen, mineral nutrients, potentially toxic elements [aluminium, iron] and performance traits (root mass, vitality, mycorrhizal colonization). Traits were measured as root community-weighed traits (RCWTs) in lowland rain forests, in rubber agro-forests mixed with rain forest trees, in rubber and oil palm plantations in two landscapes (Bukit Duabelas and Harapan, Sumatra). We hypothesized that RCWTs vary with land use system indicating increasing transformation intensity and loss of ecosystem functions. The main factors found to be related to increasing transformation intensity were declining root vitality and root sulfur, nitrogen, carbon, manganese concentrations and increasing root aluminium and iron concentrations as well as increasing spore densities of arbuscular mycorrhizas. Mycorrhizal abundance was high for arbuscular and low for ectomycorrhizas and unrelated to changes in RCWTs. The decline in RCWTs showed significant correlations with soil nitrogen, soil pH and litter carbon. Thus, our study uncovered a relationship between deteriorating root community traits and loss of ecosystem functionality and showed that increasing transformation intensity resulted in decreasing root nutrition and health. Based on these results we suggest that land management that improves root vitality may enhance the ecological functions of intense tropical production systems.

  12. Seed shadow of Swietenia macrophylla remnant trees in a Mexican rainforest: Implications for forest management

    OpenAIRE

    Alcalá, Raúl E.; Alonso, Roxalma L.; Gutiérrez-Granados, Gabriel

    2014-01-01

    The understanding of processes affecting the regeneration and coexistence of tree species is of high concern in tropical landscapes disturbed by anthropogenic activities. In this study, we evaluated the seed shadow of eight small remnant Swietenia macrophylla trees to determine the possible consequences of selective logging on the first stages of natural regeneration. We expected to find a restricted dispersal ability and a marked loss of seeds due to biotic interactions. To test this, seed s...

  13. Vegetation composition and altitudinal distribution of Andean rain forests in El Angel and Guandera reserves, northern Ecuador

    NARCIS (Netherlands)

    Moscol Olivera, M.C.; Cleef, A.M.

    2009-01-01

    Patterns of vascular plant species composition and structure of the remaining rain forest of the Andean Cordillera in northern Ecuador were studied in two reserves: Guandera and El Angel. Thirty three plots located between 3300 and 3700 in were examined along two altitudinal transects crossing the

  14. Trees and light : tree development and morphology in relation to light availability in a tropical rain forest in French Guiana

    NARCIS (Netherlands)

    Sterck, F.J.

    1997-01-01

    Tropical rain forest trees spend their life in a heterogeneous light environment. During their life history, they may change their growth in relation to different levels of light availability. Some of their physiological processes (e.g. photosynthesis, carbon allocation, and meristern

  15. Vegetation composition and altitudinal distribution of Andean rain forests in El Angel and Guandera reserves, northern Ecuador

    NARCIS (Netherlands)

    Moscol Olivera, M.C.; Cleef, A.M.

    2009-01-01

    Patterns of vascular plant species composition and structure of the remaining rain forest of the Andean Cordillera in northern Ecuador were studied in two reserves: Guandera and El Angel. Thirty three plots located between 3300 and 3700 m were examined along two altitudinal transects crossing the

  16. Diversity and dynamics of mycorrhizal associations in tropical rain forests with different disturbance regimes in South Cameroon

    NARCIS (Netherlands)

    Onguene, N.A.

    2000-01-01

    The present study documents the occurrence of mycorrhizal associations in the rain forests of south Cameroon. All species investigated are mycorrhizal. Most timber species form arbuscular mycorrhiza, but some timber species, which usually occur in clumps, form ectomycorrhiza. Species

  17. Responses of Euglossine Bees (Hymenoptera, Apidae, Euglossina) to an Edge-Forest Gradient in a Large Tabuleiro Forest Remnant in Eastern Brazil.

    Science.gov (United States)

    Coswosk, J A; Ferreira, R A; Soares, E D G; Faria, L R R

    2018-08-01

    Euglossine fauna of a large remnant of Brazilian Atlantic forest in eastern Brazil (Reserva Natural Vale) was assessed along an edge-forest gradient towards the interior of the fragment. To test the hypotheses that the structure of assemblages of orchid bees varies along this gradient, the following predictions were evaluated: (i) species richness is positively related to distance from the forest edge, (ii) species diversity is positively related to distance from the edge, (iii) the relative abundance of species associated with forest edge and/or open areas is inversely related to the distance from edge, and (iv) relative abundance of forest-related species is positively related to distance from the edge. A total of 2264 bees of 25 species was assessed at five distances from the edge: 0 m (the edge itself), 100 m, 500 m, 1000 m and 1500 m. Data suggested the existence of an edge-interior gradient for euglossine bees regarding species diversity and composition (considering the relative abundance of edge and forest-related species as a proxy for species composition) but not species richness.

  18. Effects on watershed hydrology after rain forest conversion to shifting cultivation and agroforestry in Sabah, Malaysia

    Energy Technology Data Exchange (ETDEWEB)

    Fagerberg, Nils

    1998-12-31

    A paired catchment study was conducted in Mendolong, Sabah, Malaysia, to monitor the hydrological effects from conversion of secondary rain forest to shifting cultivation and agroforestry land-uses. Four different treatments were investigated: (1.) Agroforestry with initial burning and planting of fast-growing trees (Acacia mangium) and one rotation of hill rice, (2.) Agroforestry treatment as in no. 1, but without burning, (3.) Shifting cultivation with burning and one rotation of hill rice and (4.) No burning and one rotation of hill rice. A fifth catchment was used as untreated control. Waterflow was continuously measured in the streams during 41 months, between May 1994 to November 1997. 11 months were used as a calibration period before clear-felling and treatments. The data were used to determine water budgets (precipitation, runoff and evapotranspiration), runoff increases after clear-felling and changes in streamflow regimes. Regression analyses on runoff from each catchment versus the control catchment during the calibration period were used to determine the increase in runoff after clear-felling. Some unexpected losses and gains of water across the borders of the divided catchments were detected in three of the five catchments. The estimated transferred water volumes under forest cover range between 10 % and 22 % of total runoff. After clear-felling the losses and gains of water across the borders increased. The water transfer did mainly occur as sub-surface flow, probably in more permeable parts in the lower soil profile like cracks in the bedrock. Generally, the risk of deep leakage seams to increase with distance from the ridge. Hydrological effects could still be calculated through amalgamation of two of the catchments, and since the third catchment had a stable level of water gain due to unchanged conditions in the surrounding catchments. The mean areal rainfall during the period was higher than earlier measurements in the area, 4061 mm. The mean

  19. Primate community of the tropical rain forests of Saracá-Taqüera National Forest, Pará, Brazil

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    LC. Oliveira

    Full Text Available Brazil is the richest country in the world in terms of primate species and the Amazonian rain forest is one of the richest biomes containing 15 (ca. 90% of the Neotropical primate genera. Although considered key elements in conservation strategies, there is only anecdotal information on primates for several protected areas within the region. Here we present new data on the community composition of the primates in the Saracá-Taqüera National Forest (429,600 ha, an actively mined, bauxite rich area, in Pará, Brazil. We used information from the literature, technical reports, museum data, and interviews conducted with agents from the Brazilian Institute of the Environment and Natural Renewable Resources (Instituto Brasileiro do Meio Ambiente e dos Recursos Naturais Renováveis - IBAMA and members of the local "Quilombo" community. In addition, from July 2003 to June 2007, we carried out 19 field trips ranging from 10 to15 days each, amounting to a total effort of 1,230 hours and 1,420 km of censuses, resulting in 1,034 records of eight primate species (Saguinus martinsi, Saguinus midas, Saimiri sciureus, Cebus apella, Pithecia pithecia, Chiropotes sagulatus, Ateles paniscus, and Alouatta macconelli. Two other species (Cebus olivaceus and Aotus trivirgatus were recorded only indirectly, through interviews and literature data. In all, Alouatta macconelli was the most frequently recorded species (43% of all records; while Saguinus midas and P. pithecia were the least (ca. 0.4 and 0.6% of all records. Based on our results, we discuss group sizes as well as taxonomic problems concerning the genera Pithecia and Chiropotes, for which we registered individuals displaying phenotypic geographical variation and two different forms, respectively. Despite the deforestation inherent in bauxite mining, the Saracá-Taqüera National Forest still has a remarkable richness of primate species. Our study results place this National Forest amongst the richest

  20. Diversity and aboveground biomass of lianas in the tropical seasonal rain forests of Xishuangbanna, SW China

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    Xiao-Tao Lü

    2009-06-01

    Full Text Available Lianas are important components of tropical forests and have significant impacts on the diversity, structure and dynamics of tropical forests. The present study documented the liana flora in a Chinese tropical region. Species richness, abundance, size-class distribution and spatial patterns of lianas were investigated in three 1-ha plots in tropical seasonal rain forests in Xishuangbanna, SW China. All lianas with = 2 cm diameter at breast height (dbh were measured, tagged and identified. A total of 458 liana stems belonging to 95 species (ranging from 38 to 50 species/ha, 59 genera and 32 families were recorded in the three plots. The most well-represented families were Loganiaceae, Annonceae, Papilionaceae, Apocynaceae and Rhamnaceae. Papilionaceae (14 species recorded was the most important family in the study forests. The population density, basal area and importance value index (IVI varied greatly across the three plots. Strychnos cathayensis, Byttneria grandifolia and Bousigonia mekongensis were the dominant species in terms of IVI across the three plots. The mean aboveground biomass of lianas (3 396 kg/ha accounted for 1.4% of the total community aboveground biomass. The abundance, diversity and biomass of lianas in Xishuangbanna tropical seasonal rain forests are lower than those in tropical moist and wet forests, but higher than those in tropical dry forests. This study provides new data on lianas from a geographical region that has been little-studied. Our findings emphasize that other factors beyond the amount and seasonality of precipitation should be included when considering the liana abundance patterns across scales. Rev. Biol. Trop. 57 (1-2: 211-222. Epub 2009 June 30.Las lianas son componentes importantes de los bosques tropicales y tienen importantes impactos en la diversidad, la estructura y la dinámica de los bosques tropicales. El presente estudio documenta la flora de lianas en una región tropical estacional china. La

  1. Carbon stocks in urban forest remnants: Atlanta and Baltimore as case studies. Chapter 5.

    Science.gov (United States)

    Ian D. Yesilonis; Richard V. Pouyat

    2012-01-01

    Urban environments influence carbon (C) and nitrogen (N) cycles of forest ecosystems by altering plant biomass, litter mass and chemistry, passive and active pools of C and N, and the occurrence and activity of decomposer organisms. It is difficult to determine the net effect of C storage due to the number of environmental factors exerting stress on urban forests....

  2. Sand fly population dynamics and cutaneous leishmaniasis among soldiers in an Atlantic forest remnant in northeastern Brazil.

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    Filipe Dantas-Torres

    2017-02-01

    Full Text Available Outbreaks of cutaneous leishmaniasis are relatively common among soldiers involved in nocturnal activities in tropical forests. We investigated the population dynamics of sand flies in a military training camp located in a remnant of Atlantic rainforest in northeastern Brazil, where outbreaks of cutaneous leishmaniasis have sporadically been described. From July 2012 to July 2014, light traps were monthly placed in 10 collection sites, being nine sites located near the forest edge and one near a sheep and goat stable. Light traps operated from 5:00 pm to 6:00 am, during four consecutive nights. Leishmania infection in sand flies was assessed using a fast real-time PCR assay. Cases of cutaneous leishmaniasis among soldiers were also investigated. In total, 24,606 sand flies belonging to 25 species were identified. Males (n = 12,683 predominated over females (n = 11,923. Sand flies were present during all months, being more numerous in March (n = 1,691 and April 2013 (n = 3,324. Lutzomyia choti (72.9% was the most abundant species, followed by Lutzomyia longispina (13.8%, Lutzomyia complexa (5.3%, representing together >90% of the sand flies collected. Forty cases of cutaneous leishmaniasis were recorded among soldiers from January 2012 to December 2014. Leishmania isolates were obtained from eight patients and were all characterized as Leishmania braziliensis. Soldiers and anyone overnighting in Atlantic rainforest remnants should adopt preventative measures such as the use of repellents on bare skin or clothes and insecticide-treated tents.

  3. Remnant lipoproteins

    DEFF Research Database (Denmark)

    Varbo, Anette; Nordestgaard, Børge G.

    2017-01-01

    Purpose of review: To review recent advances in the field of remnant lipoproteins and remnant cholesterol with a focus on cardiovascular disease risk. Recent findings: In line with previous years' research, current observational, genetic, and mechanistic studies find remnant lipoproteins (defined...... of cardiovascular disease risk reduction through remnant lipoprotein lowering are under way....

  4. OPTIMAL WAVELENGTH SELECTION ON HYPERSPECTRAL DATA WITH FUSED LASSO FOR BIOMASS ESTIMATION OF TROPICAL RAIN FOREST

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    T. Takayama

    2016-06-01

    Full Text Available Above-ground biomass prediction of tropical rain forest using remote sensing data is of paramount importance to continuous large-area forest monitoring. Hyperspectral data can provide rich spectral information for the biomass prediction; however, the prediction accuracy is affected by a small-sample-size problem, which widely exists as overfitting in using high dimensional data where the number of training samples is smaller than the dimensionality of the samples due to limitation of require time, cost, and human resources for field surveys. A common approach to addressing this problem is reducing the dimensionality of dataset. Also, acquired hyperspectral data usually have low signal-to-noise ratio due to a narrow bandwidth and local or global shifts of peaks due to instrumental instability or small differences in considering practical measurement conditions. In this work, we propose a methodology based on fused lasso regression that select optimal bands for the biomass prediction model with encouraging sparsity and grouping, which solves the small-sample-size problem by the dimensionality reduction from the sparsity and the noise and peak shift problem by the grouping. The prediction model provided higher accuracy with root-mean-square error (RMSE of 66.16 t/ha in the cross-validation than other methods; multiple linear analysis, partial least squares regression, and lasso regression. Furthermore, fusion of spectral and spatial information derived from texture index increased the prediction accuracy with RMSE of 62.62 t/ha. This analysis proves efficiency of fused lasso and image texture in biomass estimation of tropical forests.

  5. [Species composition and diversity of soil mesofauna in the 'Holy Hills' fragmentary tropical rain forest of Xishuangbanna, China].

    Science.gov (United States)

    Yang, X; Sha, L

    2001-04-01

    The species composition and diversity of soil mesofauna were examined in fragmented dry tropical seasonal rainforest of tow 'Holy Hills' of Dai nationality, compared with the continuous moist tropical seasonal rain forest of Nature Reserve in Xishuangbanna area. 5 sample quadrats were selected along the diagonal of 20 m x 20 m sampling plot, and the samples of litterfall and 0-3 cm soil were collected from each 50 cm x 10 cm sample quadrat. Animals in soil sample were collected by using dry-funnel(Tullgren's), were identified to their groups according to the order. The H' index, D.G index and the pattern of relative abundance of species were used to compare the diversity of soil mesofauna. The results showed that the disturbance of vegetation and soil resulted by tropical rainforest fragmentation was the major factor affecting the diversity of soil mesofauna. Because the fragmented forest was intruded by some pioneer tree species and the "dry and warm" effect operated, this forest had more litterfall on the floor and more humus in the soil than the continuous moist rain forest. The soil condition with more soil organic matter, total N and P, higher pH value and lower soil bulk density became more favorable to the soil mesofauna. Therefore, the species richness, abundance and diversity of soil mesofauna in fragmented forests were higher than those in continuous forest, but the similarity of species composition in fragmented forest to the continuous forest was minimal. Soil mesofauna diversity in fragmented forests did not change with decreasing fragmented area, indicating that there was no species-area effect operation in this forest. The pattern of relative abundance of species in these forest soils was logarithmic series distribution.

  6. Nutrient fluxes in litterfall of a secondary successional alluvial rain forest in Southern Brazil

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    Maurício Bergamini Scheer

    2011-12-01

    Full Text Available During forest succession, litterfall nutrient fluxes increase significantly. The higher inputs of organic matter and nutrients through litterfall affects positively soil fertility and the species composition, which are essential components in forest restoration and management programs. In the present study, the input of nutrients to the forest soil via litterfall components was estimated for two sites of different development stages, in an early successional alluvial rain forest in Brazil. Litterfall returned to the soil, in kg/ha, ca. 93 N, 79 Ca, 24 K, 15 Mg, 6 P, 1.7 Mn, 0.94 Fe, 0.18 Zn, 0.09 Cu and 11.2 Al, in the site where trees were more abundant and had higher values of basal area. In the other area, where trees where less abundant and values of basal area were comparatively low, litterfall returned Durante la sucesión secundaria forestal, el flujo de nutrientes en la hojarasca se incrementa significativamente. Los altos ingresos de materia orgánica y nutrientes a través de la hojarasca afecta positivamente la fertilidad del suelo y la composición de especies, las cuales son componentes esenciales para programas de restauración forestal y de manejo. En el presente estudio, el ingreso de nutrientes a través de la hojarasca y sus componentes fueron estimados para dos sitios de una selva lluviosa atlántica aluvial en sucesión temprana. La cantidad anual de elementos que ingresan al suelo desde la vegetación más desarrollada (sitios con alta área basal y abundancia de árboles fueron (en kg/ha: 93 N, 79 Ca, 24 K, 15 Mg, 6 P, 1.7 Mn, 0.94 Fe, 0.18 Zn, 0.09 Cu y 11.2 Al. Menos de la mitad de esas cantidades fueron aportadas por la vegetación menos desarrollada, excepto para el Al. La cantidad de Al aportada a este sitio fue similar a la contribución de la vegetación más desarrollada, debido a la contribución de: Tibouchina pulchra (82% de todo el Al aportado. La eficiencia en el uso de nutrientes de la hojarasca

  7. Atmospheric versus biological sources of polycyclic aromatic hydrocarbons (PAHs) in a tropical rain forest environment.

    Science.gov (United States)

    Krauss, Martin; Wilcke, Wolfgang; Martius, Christopher; Bandeira, Adelmar G; Garcia, Marcos V B; Amelung, Wulf

    2005-05-01

    To distinguish between pyrogenic and biological sources of PAHs in a tropical rain forest near Manaus, Brazil, we determined the concentrations of 21 PAHs in leaves, bark, twigs, and stem wood of forest trees, dead wood, mineral topsoil, litter layer, air, and Nasutitermes termite nest compartments. Naphthalene (NAPH) was the most abundant PAH with concentrations of 35 ng m(-3) in air (>85% of the sum of 21PAHs concentration), up to 1000 microg kg(-1) in plants (>90%), 477 microg kg(-1) in litter (>90%), 32 microg kg(-1) in topsoil (>90%), and 160 microg kg(-1) (>55%) in termite nests. In plants, the concentrations of PAHs in general decreased in the order leaves > bark > twigs > stem wood. The concentrations of most low-molecular weight PAHs in leaves and bark were near equilibrium with air, but those of NAPH were up to 50 times higher. Thus, the atmosphere seemed to be the major source of all PAHs in plants except for NAPH. Additionally, phenanthrene (PHEN) had elevated concentrations in bark and twigs of Vismia cayennensis trees (12-60 microg kg(-1)), which might have produced PHEN. In the mineral soil, perylene (PERY) was more abundant than in the litter layer, probably because of in situ biological production. Nasutitermes nests had the highest concentrations of most PAHs in exterior compartments (on average 8 and 15 microg kg(-1) compared to atmosphere controls the concentrations of most PAHs. However, the occurrence of NAPH, PHEN, and PERY in plants, termite nests, and soils at elevated concentrations supports the assumption of their biological origin.

  8. Atmospheric versus biological sources of polycyclic aromatic hydrocarbons (PAHs) in a tropical rain forest environment

    International Nuclear Information System (INIS)

    Krauss, Martin; Wilcke, Wolfgang; Martius, Christopher; Bandeira, Adelmar G.; Garcia, Marcos V.B.; Amelung, Wulf

    2005-01-01

    To distinguish between pyrogenic and biological sources of PAHs in a tropical rain forest near Manaus, Brazil, we determined the concentrations of 21 PAHs in leaves, bark, twigs, and stem wood of forest trees, dead wood, mineral topsoil, litter layer, air, and Nasutitermes termite nest compartments. Naphthalene (NAPH) was the most abundant PAH with concentrations of 35 ng m -3 in air (>85% of the Σ21PAHs concentration), up to 1000 μg kg -1 in plants (>90%), 477 μg kg -1 in litter (>90%), 32 μg kg -1 in topsoil (>90%), and 160 μg kg -1 (>55%) in termite nests. In plants, the concentrations of PAHs in general decreased in the order leaves > bark > twigs > stem wood. The concentrations of most low-molecular weight PAHs in leaves and bark were near equilibrium with air, but those of NAPH were up to 50 times higher. Thus, the atmosphere seemed to be the major source of all PAHs in plants except for NAPH. Additionally, phenanthrene (PHEN) had elevated concentrations in bark and twigs of Vismia cayennensis trees (12-60 μg kg -1 ), which might have produced PHEN. In the mineral soil, perylene (PERY) was more abundant than in the litter layer, probably because of in situ biological production. Nasutitermes nests had the highest concentrations of most PAHs in exterior compartments (on average 8 and 15 μg kg -1 compared to -1 in interior parts) and high PERY concentrations in all compartments (12-86 μg kg -1 ), indicating an in situ production of PERY in the nests. Our results demonstrate that the deposition of pyrolytic PAHs from the atmosphere controls the concentrations of most PAHs. However, the occurrence of NAPH, PHEN, and PERY in plants, termite nests, and soils at elevated concentrations supports the assumption of their biological origin. - Evidence of non-pyrolytic, biogenic production of PAHs is provided

  9. The price of gold: mercury exposure in the Amazonian rain forest.

    Science.gov (United States)

    Branches, F J; Erickson, T B; Aks, S E; Hryhorczuk, D O

    1993-01-01

    Concern has surfaced over the recent discovery of human mercury exposure throughout the tropical rain forest of South America's Amazon River Basin. The probable source of mercury has been traced to gold mines located within the interior. The mining process involves the extraction of gold from ore by burning off a mercury additive, resulting in vaporization of elemental mercury into the surrounding environment. The purpose of this case series is to document mercury levels in miners and local villagers presenting with a history of exposure, or signs and symptoms consistent with mercury toxicity. Over a five year period (1986-91), the whole blood and urine mercury levels of 55 Brazilian patients demonstrating signs and symptoms consistent with mercury exposure were collected. Thirty-three (60%) of the subjects had direct occupational exposure to mercury via gold mining and refining. Whole blood mercury levels ranged from 0.4-13.0 micrograms/dL (mean 3.05 micrograms/dL). Spot urine levels ranged 0-151 micrograms/L (mean = 32.7 micrograms/L). Occupational mercury exposure is occurring in the Amazon River Basin. Interventions aimed at altering the gold mining process while protecting the workers and surrounding villagers from the source of exposure are essential. The impact of the gold mining industry on general environmental contamination has not been investigated.

  10. Genetic structure and conservation of Mountain Lions in the South-Brazilian Atlantic Rain Forest

    Directory of Open Access Journals (Sweden)

    Camila S. Castilho

    2012-01-01

    Full Text Available The Brazilian Atlantic Rain Forest, one of the most endangered ecosystems worldwide, is also among the most important hotspots as regards biodiversity. Through intensive logging, the initial area has been reduced to around 12% of its original size. In this study we investigated the genetic variability and structure of the mountain lion, Puma concolor. Using 18 microsatellite loci we analyzed evidence of allele dropout, null alleles and stuttering, calculated the number of allele/locus, PIC, observed and expected heterozygosity, linkage disequilibrium, Hardy-Weinberg equilibrium, F IS, effective population size and genetic structure (MICROCHECKER, CERVUS, GENEPOP, FSTAT, ARLEQUIN, ONESAMP, LDNe, PCAGEN, GENECLASS software,we also determine whether there was evidence of a bottleneck (HYBRIDLAB, BOTTLENECK software that might influence the future viability of the population in south Brazil. 106 alleles were identified, with the number of alleles/locus ranging from 2 to 11. Mean observed heterozygosity, mean number of alleles and polymorphism information content were 0.609, 5.89, and 0.6255, respectively. This population presented evidence of a recent bottleneck and loss of genetic variation. Persistent regional poaching constitutes an increasing in the extinction risk.

  11. Species association in tropical montane rain forest at two successional stages in Diaoluo Mountain, Hainan

    Institute of Scientific and Technical Information of China (English)

    Fude LIU; Wenjin WANG; Ming ZHANG; Jianwei ZHENG; Zhongsheng WANG; Shiting ZHANG; Wenjie YANG; Shuqing AN

    2008-01-01

    Species association is one of the basic concepts in community succession. There are different viewpoints on how species interaction changes with the progress of succession. In order to assess these relationships, we examined species associations in the tropical montane rain forest at early and late successional stages in Diaoluo Mountain, Hainan Island. Based on data from a 2 × 2 contingency table of species presence or absence, statist-ical methods including analysis of species association and χ2 tests were applied. The results show that: 1) an overall positive association was present among tree species in the communities during the two successional stages and were statistically significant at the late stage. The number of species pairs with positive and negative associations decreased throughout the process of succession, while the number with null associations was greatly increased. The same trend existed among the dominant and compan-ion species. The results indicate that the communities are developing towards a stable stage where the woody species coexist in harmony. 2) In the early-established and later invading species, all positive associations were not signifi-cant. Compared with positive and null associations, fewer negative associations were found. This implies that these species are inclined to coexist independently through por-tioning of resources. 3) Among the later invading species, positive associations were significant and no negative associations were found which suggest that these species have similar adaptive ability in the habitat and occupied overlapping niches in the community.

  12. Seed rain, soil seed bank, seed loss and regeneration of Castanopsis fargesii (Fagaceae) in a subtropical evergreen broad-leaved forest

    Science.gov (United States)

    Xiaojun Du; Qinfeng Guo; Xianming Gao; Keping Na

    2007-01-01

    Understanding the seed rain and seed loss dynamics in the natural condition has important significance for revealing the natural regeneration mechanisms.We conducted a 3-year field observation on seed rain, seed loss and natural regeneration of Castanopsis fargesii Franch., a dominant tree species in evergreen broad-leaved forests in Dujiangyan,...

  13. Seasonality of weather and tree phenology in a tropical evergreen mountain rain forest.

    Science.gov (United States)

    Bendix, J; Homeier, J; Cueva, E Ortiz; Emck, P; Breckle, S-W; Richter, M; Beck, E

    2006-07-01

    Flowering and fruiting as phenological events of 12 tree species in an evergreen tropical mountain rain forest in southern Ecuador were examined over a period of 3-4 years. Leaf shedding of two species was observed for 12 months. Parallel to the phenological recordings, meteorological parameters were monitored in detail and related to the flowering and fruiting activity of the trees. In spite of the perhumid climate of that area, a high degree of intra- and inter-specific synchronisation of phenological traits was apparent. With the exception of one species that flowered more or less continuously, two groups of trees could be observed, one of which flowered during the less humid months (September to October) while the second group started to initiate flowers towards the end of that phase and flowered during the heavy rains (April to July). As reflected by correlation coefficients, the all-time series of meteorological parameters showed a distinct seasonality of 8-12 months, apparently following the quasi-periodic oscillation of precipitation and related cloudiness. As revealed by power spectrum analysis and Markov persistence, rainfall and minimum temperature appear to be the only parameters with a periodicity free of long-term variations. The phenological events of most of the plant species showed a similar periodicity of 8-12 months, which followed the annual oscillation of relatively less and more humid periods and thus was in phase or in counter-phase with the oscillations of the meteorological parameters. Periods of unusual cold or dryness, presumably resulting from underlying longer-term trends or oscillations (such as ENSO), affected the homogeneity of quasi-12-month flowering events, fruit maturation and also the production of germinable seeds. Some species show underlying quasi-2-year-oscillations, for example that synchronise with the development of air temperature; others reveal an underlying decrease or increase in flowering activity over the

  14. Genetic diversity of Casearia sylvestris populations in remnants of the Atlantic Forest.

    Science.gov (United States)

    Araujo, F L; Siqueira, M V B M; Grando, C; Viana, J P G; Pinheiro, J B; Alves-Pereira, A; Campos, J B; Brancalion, P H S; Zucchi, M I

    2017-01-23

    Guaçatonga (Casearia sylvestris) is a native plant of the Atlantic Forest, with high medicinal potential and relevance for reforestation programs. The aim of this study was to characterize, with microsatellite markers, two populations of C. sylvestris from remaining areas of the Atlantic Forest in the State of São Paulo. High allelic variation was found in both populations (N A = 101 and 117; A R = 12.5 and 14.4), although with high endogamy coefficients (f = 0.640 and 0.363). Estimates of genetic structure suggested the presence of considerable genetic divergence between the populations (F ST = 0.103); however, there was no spatial genetic structure within the populations. Genetic divergence may have occurred due to decreased gene flow between the fragmented populations as the result of deforestation. The results of this study demonstrate the importance of genetic diversity and its characterization in native plants within remaining forest areas for the management and restoration of such areas.

  15. Seed rain dynamics following disturbance exclusion in a secondary tropical dry forest in Morelos, Mexico

    Directory of Open Access Journals (Sweden)

    Eliane Ceccon

    2009-06-01

    Full Text Available In most of the legally protected areas in Mexico local inhabitants use natural resources, such as fire wood or cattle grazing. These frequent but low-intensity disturbances have consequences at various levels of the tropical ecosystems and strongly impact forest structure and its regeneration capacity. Despite their importance, the effects of these perturbations in many aspects of tropical forest ecology and in the forest’s capacity to recover after disturbance exclusion remain poorly understood. Understanding the impact of these processes on tropical forests is necessary for rehabilitating these forests and enhancing their productivity. In this study, we evaluate the impact of twelve years of exclusion (E of cattle grazing and fire wood extraction in the composition and dynamics of seed rain, and compare this assessment to a similar analysis in an area where these perturbations continued (without exclusion, WE. We found a strong seasonality in seed rain (96% of seeds fell in the dry season in both areas. There were no significant differences between E and WE sites in relation to overall seed density, species richness and diversity. However, the distribution along the year of seed species density was significantly different among the E and WE sites. The Jaccard’s similarity index between E and WE sites was relatively low (0.57. Barochory was the most common dispersal mode observed among the 23 species in terms of seed species density (48%, followed by anemochory (39% and zoochory (13%. In relation to seed density, anemochory was the most frequent dispersal mode (88%. Most species in the zone were categorized as small seeds (92%, and there were no significant differences in the distribution of seed size between E and WE. The spatial pattern of dispersal of the four species with the highest relative importance value index, in both areas, was aggregated. Twelve years of disturbance exclusion were not enough to fully restore the seed rain of the

  16. Influence of Salinity on Bacterioplankton Communities from the Brazilian Rain Forest to the Coastal Atlantic Ocean

    Science.gov (United States)

    Silveira, Cynthia B.; Vieira, Ricardo P.; Cardoso, Alexander M.; Paranhos, Rodolfo; Albano, Rodolpho M.; Martins, Orlando B.

    2011-01-01

    Background Planktonic bacteria are recognized as important drivers of biogeochemical processes in all aquatic ecosystems, however, the taxa that make up these communities are poorly known. The aim of this study was to investigate bacterial communities in aquatic ecosystems at Ilha Grande, Rio de Janeiro, Brazil, a preserved insular environment of the Atlantic rain forest and how they correlate with a salinity gradient going from terrestrial aquatic habitats to the coastal Atlantic Ocean. Methodology/Principal Findings We analyzed chemical and microbiological parameters of water samples and constructed 16S rRNA gene libraries of free living bacteria obtained at three marine (two coastal and one offshore) and three freshwater (water spring, river, and mangrove) environments. A total of 836 sequences were analyzed by MOTHUR, yielding 269 freshwater and 219 marine operational taxonomic units (OTUs) grouped at 97% stringency. Richness and diversity indexes indicated that freshwater environments were the most diverse, especially the water spring. The main bacterial group in freshwater environments was Betaproteobacteria (43.5%), whereas Cyanobacteria (30.5%), Alphaproteobacteria (25.5%), and Gammaproteobacteria (26.3%) dominated the marine ones. Venn diagram showed no overlap between marine and freshwater OTUs at 97% stringency. LIBSHUFF statistics and PCA analysis revealed marked differences between the freshwater and marine libraries suggesting the importance of salinity as a driver of community composition in this habitat. The phylogenetic analysis of marine and freshwater libraries showed that the differences in community composition are consistent. Conclusions/Significance Our data supports the notion that a divergent evolutionary scenario is driving community composition in the studied habitats. This work also improves the comprehension of microbial community dynamics in tropical waters and how they are structured in relation to physicochemical parameters

  17. Herbivory of tropical rain forest tree seedlings correlates with future mortality.

    Science.gov (United States)

    Eichhorn, Markus P; Nilus, Reuben; Compton, Stephen G; Hartley, Sue E; Burslem, David F R P

    2010-04-01

    Tree seedlings in tropical rain forests are subject to both damage from natural enemies and intense interspecific competition. This leads to a trade-off in investment between defense and growth, and it is likely that tree species specialized to particular habitats tailor this balance to correspond with local resource availability. It has also been suggested that differential herbivore impacts among tree species may drive habitat segregation, favoring species adapted to particular resource conditions. In order to test these predictions, a reciprocal transplant experiment in Sabah, Malaysia, was established with seedlings of five species of Dipterocarpaceae. These were specialized to either alluvial (Hopea nervosa, Parashorea tomentella) or sandstone soils (Shorea multiflora, H. beccariana), or were locally absent (S. fallax). A total of 3000 seedlings were planted in paired gap and understory plots in five sites on alluvial and sandstone soils. Half of all seedlings were fertilized. Seedling growth and mortality were recorded in regular samples over 3.5 years, and rates of insect herbivore damage were estimated from censuses of foliar tissue loss on marked mature leaves and available young leaves. Greater herbivory rates on mature leaves had no measurable effects on seedling growth but were associated with a significantly increased likelihood of mortality during the following year. In contrast, new-leaf herbivory rates correlated with neither growth nor mortality. There were no indications of differential impacts of herbivory among the five species, nor between experimental treatments. Herbivory was not shown to influence segregation of species between soil types, although it may contribute toward differential survival among light habitats. Natural rates of damage were substantially lower than have been shown to influence tree seedling growth and mortality in previous manipulative studies.

  18. Influence of salinity on bacterioplankton communities from the Brazilian rain forest to the coastal Atlantic Ocean.

    Science.gov (United States)

    Silveira, Cynthia B; Vieira, Ricardo P; Cardoso, Alexander M; Paranhos, Rodolfo; Albano, Rodolpho M; Martins, Orlando B

    2011-03-09

    Planktonic bacteria are recognized as important drivers of biogeochemical processes in all aquatic ecosystems, however, the taxa that make up these communities are poorly known. The aim of this study was to investigate bacterial communities in aquatic ecosystems at Ilha Grande, Rio de Janeiro, Brazil, a preserved insular environment of the Atlantic rain forest and how they correlate with a salinity gradient going from terrestrial aquatic habitats to the coastal Atlantic Ocean. We analyzed chemical and microbiological parameters of water samples and constructed 16S rRNA gene libraries of free living bacteria obtained at three marine (two coastal and one offshore) and three freshwater (water spring, river, and mangrove) environments. A total of 836 sequences were analyzed by MOTHUR, yielding 269 freshwater and 219 marine operational taxonomic units (OTUs) grouped at 97% stringency. Richness and diversity indexes indicated that freshwater environments were the most diverse, especially the water spring. The main bacterial group in freshwater environments was Betaproteobacteria (43.5%), whereas Cyanobacteria (30.5%), Alphaproteobacteria (25.5%), and Gammaproteobacteria (26.3%) dominated the marine ones. Venn diagram showed no overlap between marine and freshwater OTUs at 97% stringency. LIBSHUFF statistics and PCA analysis revealed marked differences between the freshwater and marine libraries suggesting the importance of salinity as a driver of community composition in this habitat. The phylogenetic analysis of marine and freshwater libraries showed that the differences in community composition are consistent. Our data supports the notion that a divergent evolutionary scenario is driving community composition in the studied habitats. This work also improves the comprehension of microbial community dynamics in tropical waters and how they are structured in relation to physicochemical parameters. Furthermore, this paper reveals for the first time the pristine

  19. Spatial distribution and interspecific associations of tree species in a tropical seasonal rain forest of China.

    Directory of Open Access Journals (Sweden)

    Guoyu Lan

    Full Text Available Studying the spatial pattern and interspecific associations of plant species may provide valuable insights into processes and mechanisms that maintain species coexistence. Point pattern analysis was used to analyze the spatial distribution patterns of twenty dominant tree species, their interspecific spatial associations and changes across life stages in a 20-ha permanent plot of seasonal tropical rainforest in Xishuangbanna, China, to test mechanisms maintaining species coexistence. Torus-translation tests were used to quantify positive or negative associations of the species to topographic habitats. The results showed: (1 fourteen of the twenty tree species were negatively (or positively associated with one or two of the topographic variables, which evidences that the niche contributes to the spatial pattern of these species. (2 Most saplings of the study species showed a significantly clumped distribution at small scales (0-10 m which was lost at larger scales (10-30 m. (3 The degree of spatial clumping deceases from saplings, to poles, to adults indicates that density-dependent mortality of the offspring is ubiquitous in species. (4 It is notable that a high number of positive small-scale interactions were found among the twenty species. For saplings, 42.6% of all combinations of species pairs showed positive associations at neighborhood scales up to five meters, but only 38.4% were negative. For poles and adults, positive associations at these distances still made up 45.5% and 29.5%, respectively. In conclusion, there is considerable evidence for the presence of positive interactions among the tree species, which suggests that species herd protection may occur in our plot. In addition, niche assembly and limited dispersal (likely contribute to the spatial patterns of tree species in the tropical seasonal rain forest in Xishuangbanna, China.

  20. Influence of salinity on bacterioplankton communities from the Brazilian rain forest to the coastal Atlantic Ocean.

    Directory of Open Access Journals (Sweden)

    Cynthia B Silveira

    Full Text Available BACKGROUND: Planktonic bacteria are recognized as important drivers of biogeochemical processes in all aquatic ecosystems, however, the taxa that make up these communities are poorly known. The aim of this study was to investigate bacterial communities in aquatic ecosystems at Ilha Grande, Rio de Janeiro, Brazil, a preserved insular environment of the Atlantic rain forest and how they correlate with a salinity gradient going from terrestrial aquatic habitats to the coastal Atlantic Ocean. METHODOLOGY/PRINCIPAL FINDINGS: We analyzed chemical and microbiological parameters of water samples and constructed 16S rRNA gene libraries of free living bacteria obtained at three marine (two coastal and one offshore and three freshwater (water spring, river, and mangrove environments. A total of 836 sequences were analyzed by MOTHUR, yielding 269 freshwater and 219 marine operational taxonomic units (OTUs grouped at 97% stringency. Richness and diversity indexes indicated that freshwater environments were the most diverse, especially the water spring. The main bacterial group in freshwater environments was Betaproteobacteria (43.5%, whereas Cyanobacteria (30.5%, Alphaproteobacteria (25.5%, and Gammaproteobacteria (26.3% dominated the marine ones. Venn diagram showed no overlap between marine and freshwater OTUs at 97% stringency. LIBSHUFF statistics and PCA analysis revealed marked differences between the freshwater and marine libraries suggesting the importance of salinity as a driver of community composition in this habitat. The phylogenetic analysis of marine and freshwater libraries showed that the differences in community composition are consistent. CONCLUSIONS/SIGNIFICANCE: Our data supports the notion that a divergent evolutionary scenario is driving community composition in the studied habitats. This work also improves the comprehension of microbial community dynamics in tropical waters and how they are structured in relation to physicochemical

  1. Soil respiration in tropical seasonal rain forest in Xishuangbanna, SW China

    Institute of Scientific and Technical Information of China (English)

    SHA; Liqing; ZHENG; Zheng; TANG; Jianwei; WANG; Yinghong

    2005-01-01

    With the static opaque chamber and gas chromatography technique, from January 2003 to January 2004 soil respiration was investigated in a tropical seasonal rain forest in Xishuangbanna, SW China. In this study three treatments were applied, each with three replicates: A (bare soil), B (soil+litter), and C (soil+litter+seedling). The results showed that soil respiration varied seasonally, low from December 2003 to February 2004, and high from June to July 2004. The annual average values of CO2 efflux from soil respiration differed among the treatments at 1% level, with the rank of C (14642 mgCO2· m-2. h-1)>B (12807 mgCO2· m-2. h-1)>A (9532 mgCO2· m-2. h-1). Diurnal variation in soil respiration was not apparent due to little diurnal temperate change in Xishuangbanna. There was a parabola relationship between soil respiration and soil moisture at 1% level. Soil respiration rates were higher when soil moisture ranged from 35% to 45%. There was an exponential relationship between soil respiration and soil temperature (at a depth of 5cm in mineral soil) at 1% level. The calculated Q1o values in this study,ranging from 2.03 to 2.36, were very near to those of tropical soil reported. The CO2 efflux in 2003was 5.34 kgCO2· m-2. a-1 from soil plus litter plus seedling, of them 3.48 kgCO2· m-2. a-1 from soil (accounting for 62.5%), 1.19 kgCO2· m-2. a-1 from litter (22.3%) and 0.67 kgCO2·m-2. a-1 from seedling (12.5%).

  2. Removal rates of native and exotic dung by dung beetles (Scarabaeidae: Scarabaeinae) in a fragmented tropical rain forest.

    Science.gov (United States)

    Amézquita, Sandra; Favila, Mario E

    2010-04-01

    Many studies have evaluated the effect of forest fragmentation on dung beetle assemblage structure. However, few have analyzed how forest fragmentation affects the processes carried out by these insects in tropical forests where their food sources consist mainly of dung produced by native herbivore mammals. With the conversion of forests to pastures, cattle dung has become an exotic alternative and abundant food for dung beetles. This study compares dung removal rates of native (monkey) and exotic (cow) dung in different-sized fragments of tropical rain forests, during the dry and rainy seasons at the Los Tuxtlas Biosphere Reserve. Dung removal rates were affected by season, dung type, and the interaction between resource type and season. During the dry season, the removal rates of monkey dung were somewhat similar than during the rainy season, whereas the removal rates of cow dung were much higher during the rainy season. Dung beetle biomass and species richness were almost three times greater in monkey dung than in cow dung. Monkey dung attracted species belonging to the dweller, roller, and tunneler guilds; cow dung attracted mostly tunnelers. Therefore, the use of exotic dung may result in a biased misconception of the rates of dung removal in tropical forest and an underestimation of dung beetle diversity. This study highlights the importance of working with natural tropical forest resources when attempting to identify realistic tendencies concerning processes in natural habitats and those modified by fragmentation and by other human activities.

  3. Nitrogen and phosphorus resorption in a neotropical rain forest of a nutrient-rich soil

    Directory of Open Access Journals (Sweden)

    José Luis Martínez-Sánchez

    2005-09-01

    Full Text Available In tropical forests with nutrient-rich soil tree’s nutrient resorption from senesced leaves has not always been observed to be low. Perhaps this lack of consistence is partly owing to the nutrient resorption methods used. The aim of the study was to analyse N and P resorption proficiency from tropical rain forest trees in a nutrient-rich soil. It was hypothesised that trees would exhibit low nutrient resorption in a nutrient-rich soil. The soil concentrations of total N and extractable P, among other physical and chemical characteristics, were analysed in 30 samples in the soil surface (10 cm of three undisturbed forest plots at ‘Estación de Biología Los Tuxtlas’ on the east coast of Mexico (18°34’ - 18°36’ N, 95°04’ - 95°09’ W. N and P resorption proficiency were determined from senescing leaves in 11 dominant tree 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. Soil was rich in total N (0.50%, n = 30 and extractable P (4.11 µg g-1, n = 30. As expected, trees showed incomplete N (1.13%, n = 11 and P (0.11%, n = 11 resorption. With a more accurate method of nutrient resorption assessment, it is possible to prove that a forest community with a nutrient-rich soil can have low levels of N and P resorption. Rev. Biol. Trop. 53(3-4: 353-359. Epub 2005 Oct 3.En las selvas tropicales con suelos fértiles se ha observado que la reabsorción de nutrientes de los arboles de las hojas seniles no siempre es baja. Esta falta de consistencia en el resultado es talvez debida en parte a la metodología de reabsorción de nutrientes utilizada. El objetivo de este estudio fue analizar la reabsorción final de N y P de arboles de la selva húmeda tropical en un suelo rico en nutrientes. La hipótesis planteada fue que en un suelo rico en nutrientes los arboles presentarían una baja reabsorción final de

  4. Remnant lipoproteins.

    Science.gov (United States)

    Varbo, Anette; Nordestgaard, Børge G

    2017-08-01

    To review recent advances in the field of remnant lipoproteins and remnant cholesterol with a focus on cardiovascular disease risk. In line with previous years' research, current observational, genetic, and mechanistic studies find remnant lipoproteins (defined in different ways) to be involved in atherosclerosis development and cardiovascular disease risk. High concentrations of remnant cholesterol could explain some of the residual risk of cardiovascular disease seen after LDL cholesterol lowering. This will be increasingly important as populations worldwide become more obese and more have diabetes, both of which elevate remnant cholesterol concentrations. Many smaller scale studies and post hoc analyses show that remnant cholesterol can be lowered by different types of drugs; however, results from large scale studies with the primary aim of reducing cardiovascular disease risk through lowering of remnant cholesterol in individuals with elevated concentrations are still missing, although some are under way. Remnant cholesterol is a risk factor for cardiovascular disease, and can be lowered by different types of drugs; however, large scale studies of cardiovascular disease risk reduction through remnant lipoprotein lowering are under way.

  5. Fagaceae tree species allocate higher fraction of nitrogen to photosynthetic apparatus than Leguminosae in Jianfengling tropical montane rain forest, China.

    Science.gov (United States)

    Tang, Jingchao; Cheng, Ruimei; Shi, Zuomin; Xu, Gexi; Liu, Shirong; Centritto, Mauro

    2018-01-01

    Variation in photosynthetic-nitrogen use efficiency (PNUE) is generally affected by several factors such as leaf nitrogen allocation and leaf diffusional conductances to CO2, although it is still unclear which factors significantly affect PNUE in tropical montane rain forest trees. In this study, comparison of PNUE, photosynthetic capacity, leaf nitrogen allocation, and diffusional conductances to CO2 between five Fagaceae tree species and five Leguminosae tree species were analyzed in Jianfengling tropical montane rain forest, Hainan Island, China. The result showed that PNUE of Fagaceae was significantly higher than that of Leguminosae (+35.5%), attributed to lower leaf nitrogen content per area (Narea, -29.4%). The difference in nitrogen allocation was the main biochemical factor that influenced interspecific variation in PNUE of these tree species. Fagaceae species allocated a higher fraction of leaf nitrogen to the photosynthetic apparatus (PP, +43.8%), especially to Rubisco (PR, +50.0%) and bioenergetics (PB +33.3%) in comparison with Leguminosae species. Leaf mass per area (LMA) of Leguminosae species was lower than that of Fagaceae species (-15.4%). While there was no significant difference shown for mesophyll conductance (gm), Fagaceae tree species may have greater chloroplast to total leaf surface area ratios and that offset the action of thicker cell walls on gm. Furthermore, weak negative relationship between nitrogen allocation in cell walls and in Rubisco was found for Castanopsis hystrix, Cyclobalanopsis phanera and Cy. patelliformis, which might imply that nitrogen in the leaves was insufficient for both Rubisco and cell walls. In summary, our study concluded that higher PNUE might contribute to the dominance of most Fagaceae tree species in Jianfengling tropical montane rain forest.

  6. Fagaceae tree species allocate higher fraction of nitrogen to photosynthetic apparatus than Leguminosae in Jianfengling tropical montane rain forest, China

    Science.gov (United States)

    Cheng, Ruimei; Shi, Zuomin; Xu, Gexi; Liu, Shirong; Centritto, Mauro

    2018-01-01

    Variation in photosynthetic-nitrogen use efficiency (PNUE) is generally affected by several factors such as leaf nitrogen allocation and leaf diffusional conductances to CO2, although it is still unclear which factors significantly affect PNUE in tropical montane rain forest trees. In this study, comparison of PNUE, photosynthetic capacity, leaf nitrogen allocation, and diffusional conductances to CO2 between five Fagaceae tree species and five Leguminosae tree species were analyzed in Jianfengling tropical montane rain forest, Hainan Island, China. The result showed that PNUE of Fagaceae was significantly higher than that of Leguminosae (+35.5%), attributed to lower leaf nitrogen content per area (Narea, –29.4%). The difference in nitrogen allocation was the main biochemical factor that influenced interspecific variation in PNUE of these tree species. Fagaceae species allocated a higher fraction of leaf nitrogen to the photosynthetic apparatus (PP, +43.8%), especially to Rubisco (PR, +50.0%) and bioenergetics (PB +33.3%) in comparison with Leguminosae species. Leaf mass per area (LMA) of Leguminosae species was lower than that of Fagaceae species (-15.4%). While there was no significant difference shown for mesophyll conductance (gm), Fagaceae tree species may have greater chloroplast to total leaf surface area ratios and that offset the action of thicker cell walls on gm. Furthermore, weak negative relationship between nitrogen allocation in cell walls and in Rubisco was found for Castanopsis hystrix, Cyclobalanopsis phanera and Cy. patelliformis, which might imply that nitrogen in the leaves was insufficient for both Rubisco and cell walls. In summary, our study concluded that higher PNUE might contribute to the dominance of most Fagaceae tree species in Jianfengling tropical montane rain forest. PMID:29390007

  7. Tree diversity, composition, forest structure and aboveground biomass dynamics after single and repeated fire in a Bornean rain forest

    NARCIS (Netherlands)

    Slik, J.W.F.; Bernard, C.S.; Beek, van M.; Breman, F.C.; Eichhorn, K.A.O.

    2008-01-01

    Forest fires remain a devastating phenomenon in the tropics that not only affect forest structure and biodiversity, but also contribute significantly to atmospheric CO2. Fire used to be extremely rare in tropical forests, leaving ample time for forests to regenerate to pre-fire conditions. In recent

  8. Optical properties of aerosols over a tropical rain forest in Xishuangbanna, South Asia

    Science.gov (United States)

    Ma, Yongjing; Xin, Jinyuan; Zhang, Wenyu; Wang, Yuesi

    2016-09-01

    Observation and analysis of the optical properties of atmospheric aerosols in a South Asian tropical rain forest showed that the annual mean aerosol optical depth (AOD) and aerosol Ångström exponent (α) at 500 nm were 0.47 ± 0.30 (± value represents the standard deviation) and 1.35 ± 0.32, respectively, from 2012 to 2014, similar with that of Amazon region. Aerosol optical properties in this region varied significantly between the dry and wet seasons. The mean AOD and α were 0.50 ± 0.32 and 1.41 ± 0.28, respectively, in the dry season and 0.41 ± 0.20 and 1.13 ± 0.41 in the wet season. Because of the combustion of the rich biomass in the dry season, fine modal smoke aerosols increased, which led to a higher AOD and smaller aerosol control mode than in the wet season. The average atmospheric humidity in the wet season was 85.50%, higher than the 79.67% during the dry season. In the very damp conditions of the wet season, the aerosol control mode was relatively larger, while AOD appeared to be lower because of the effect of aerosol hygroscopic growth and wet deposition. The trajectories were similar both in dry and wet, but with different effects on the aerosol concentration. The highest AOD values 0.66 ± 0.34 (in dry) and 0.45 ± 0.21 (in wet) both occurred in continental air masses, while smaller (0.38-0.48 in dry and 0.30-0.35 in wet) in oceanic air masses. The range of AOD values during the wet season was relatively narrow (0.30-0.45), but the dry season range was wider (0.38-0.66). For the Ångström exponent, the range in the wet season (0.74-1.34) was much greater than that in the dry season (1.33-1.54).

  9. Feeding behavior by hummingbirds (Aves: Trochilidae in artificial food patches in an Atlantic Forest remnant in southeastern Brazil

    Directory of Open Access Journals (Sweden)

    Lucas L. Lanna

    2017-06-01

    Full Text Available ABSTRACT During flight, hummingbirds achieve the maximum aerobic metabolism rates within vertebrates. To meet such demands, these birds have to take in as much energy as possible, using strategies such as selecting the best food resources and adopting behaviors that allow the greatest energy gains. We tested whether hummingbirds choose sources that have higher sugar concentrations, and investigated their behaviors near and at food resources. The study was conducted at Atlantic forest remnant in Brazil, between June and December 2012. Four patches were provided with artificial feeders, containing sucrose solutions at concentrations of 5%, 15%, 25% and 35% weight/volume. Hummingbird behaviors were recorded using the ad libitum method with continuous recording of behaviors. The following species were observed: the Brazilian ruby Clytolaema rubricauda (Boddaert, 1783, Violet-capped woodnymph Thalurania glaucopis (Gmelin, 1788, Scale-throated hermit Phaethornis eurynome (Lesson, 1832, White-throated hummingbird Leucochloris albicollis (Vieillot, 1818, Versicoloured emerald Amazilia versicolor (Vieillot, 1818, Glittering-bellied emerald Chlorostilbon lucidus (Shaw, 1812 and other Phaethornis spp. C. rubricauda, P. eurynome and Phaethornis spp. visited the 35%-sucrose feeders more often, while the T. glaucopis visited the 25%-sucrose feeders more often. L. albicollis and A. versicolor visited more often solutions with sugar concentration of 15%. C. lucidus visited all patches equally. Three behavioral strategies were observed: 1 C. rubricauda and T. glaucopis exhibited interspecific and intraspecific dominance; 2 the remaining species exhibited subordinance to the dominant hummingbirds, and 3 P. eurynome and Phaethornis spp. adopted a hide-and-wait strategy to the dominant hummingbird species. The frequency of aggressive behaviors was correlated with the time the hummingbird spent feeding, and bird size. Our results showed that hummingbirds can adopt

  10. Towards ground-truthing of spaceborne estimates of above-ground biomass and leaf area index in tropical rain forests

    Science.gov (United States)

    Köhler, P.; Huth, A.

    2010-05-01

    The canopy height of forests is a key variable which can be obtained using air- or spaceborne remote sensing techniques such as radar interferometry or lidar. If new allometric relationships between canopy height and the biomass stored in the vegetation can be established this would offer the possibility for a global monitoring of the above-ground carbon content on land. In the absence of adequate field data we use simulation results of a tropical rain forest growth model to propose what degree of information might be generated from canopy height and thus to enable ground-truthing of potential future satellite observations. We here analyse the correlation between canopy height in a tropical rain forest with other structural characteristics, such as above-ground biomass (AGB) (and thus carbon content of vegetation) and leaf area index (LAI). The process-based forest growth model FORMIND2.0 was applied to simulate (a) undisturbed forest growth and (b) a wide range of possible disturbance regimes typically for local tree logging conditions for a tropical rain forest site on Borneo (Sabah, Malaysia) in South-East Asia. It is found that for undisturbed forest and a variety of disturbed forests situations AGB can be expressed as a power-law function of canopy height h (AGB=a·hb) with an r2~60% for a spatial resolution of 20 m×20 m (0.04 ha, also called plot size). The regression is becoming significant better for the hectare wide analysis of the disturbed forest sites (r2=91%). There seems to exist no functional dependency between LAI and canopy height, but there is also a linear correlation (r2~60%) between AGB and the area fraction in which the canopy is highly disturbed. A reasonable agreement of our results with observations is obtained from a comparison of the simulations with permanent sampling plot data from the same region and with the large-scale forest inventory in Lambir. We conclude that the spaceborne remote sensing techniques have the potential to

  11. Acid Rain

    Science.gov (United States)

    Bricker, Owen P.; Rice, Karen C.

    1995-01-01

    Although acid rain is fading as a political issue in the United States and funds for research in this area have largely disappeared, the acidity of rain in the Eastern United States has not changed significantly over the last decade, and it continues to be a serious environmental problem. Acid deposition (commonly called acid rain) is a term applied to all forms of atmospheric deposition of acidic substances - rain, snow, fog, acidic dry particulates, aerosols, and acid-forming gases. Water in the atmosphere reacts with certain atmospheric gases to become acidic. For example, water reacts with carbon dioxide in the atmosphere to produce a solution with a pH of about 5.6. Gases that produce acids in the presence of water in the atmosphere include carbon dioxide (which converts to carbonic acid), oxides of sulfur and nitrogen (which convert to sulfuric and nitric acids}, and hydrogen chloride (which converts to hydrochloric acid). These acid-producing gases are released to the atmosphere through natural processes, such as volcanic emissions, lightning, forest fires, and decay of organic matter. Accordingly, precipitation is slightly acidic, with a pH of 5.0 to 5.7 even in undeveloped areas. In industrialized areas, most of the acid-producing gases are released to the atmosphere from burning fossil fuels. Major emitters of acid-producing gases include power plants, industrial operations, and motor vehicles. Acid-producing gases can be transported through the atmosphere for hundreds of miles before being converted to acids and deposited as acid rain. Because acids tend to build up in the atmosphere between storms, the most acidic rain falls at the beginning of a storm, and as the rain continues, the acids "wash out" of the atmosphere.

  12. Elevational change in woody tissue CO2 efflux in a tropical mountain rain forest in southern Ecuador

    International Nuclear Information System (INIS)

    Zach, A.; Horna, V.; Leuschner, C.

    2008-01-01

    A study was conducted to quantify species-specific differences in wood tissue respiration in tropical mountain forests. The respiratory activity of stems and coarse roots were compared, and changes in stem and root respiration along an altitudinal span of 2000 m in a rain forest in Ecuador were analyzed. Stem and root carbon dioxide (CO 2 ) efflux of trees were investigated using an open gas exchange system while stand microclimate was also monitored. Results of the study demonstrated substantial variations in respiratory activity among the different species of trees. Mean daily CO 2 release rates declined, and mean daily CO 2 released from coarse roots decreased with altitude. Higher stem to coarse root respiration rates were observed at lower elevations. It was concluded that decreases in stem respiration coincided with a significant decrease in relative stem diameter increment and increases in fine and coarse root biomass production. 34 refs., 3 tabs., 3 figs

  13. Ant mosaics in Bornean primary rain forest high canopy depend on spatial scale, time of day, and sampling method

    Directory of Open Access Journals (Sweden)

    Kalsum M. Yusah

    2018-01-01

    Full Text Available Background Competitive interactions in biological communities can be thought of as giving rise to “assembly rules” that dictate the species that are able to co-exist. Ant communities in tropical canopies often display a particular pattern, an “ant mosaic”, in which competition between dominant ant species results in a patchwork of mutually exclusive territories. Although ant mosaics have been well-documented in plantation landscapes, their presence in pristine tropical forests remained contentious until recently. Here we assess presence of ant mosaics in a hitherto under-investigated forest stratum, the emergent trees of the high canopy in primary tropical rain forest, and explore how the strength of any ant mosaics is affected by spatial scale, time of day, and sampling method. Methods To test whether these factors might impact the detection of ant mosaics in pristine habitats, we sampled ant communities from emergent trees, which rise above the highest canopy layers in lowland dipterocarp rain forests in North Borneo (38.8–60.2 m, using both baiting and insecticide fogging. Critically, we restricted sampling to only the canopy of each focal tree. For baiting, we carried out sampling during both the day and the night. We used null models of species co-occurrence to assess patterns of segregation at within-tree and between-tree scales. Results The numerically dominant ant species on the emergent trees sampled formed a diverse community, with differences in the identity of dominant species between times of day and sampling methods. Between trees, we found patterns of ant species segregation consistent with the existence of ant mosaics using both methods. Within trees, fogged ants were segregated, while baited ants were segregated only at night. Discussion We conclude that ant mosaics are present within the emergent trees of the high canopy of tropical rain forest in Malaysian Borneo, and that sampling technique, spatial scale, and time

  14. Revealing Forest Harvesting Effects on Large Peakflows in Rain-On-Snow Environment with a New Stochastic Framework

    Science.gov (United States)

    Rong, W. N.; Alila, Y.

    2017-12-01

    Using nine pairs of control-treatment watersheds with varying climate, physiography, and harvesting practices in the Rain-On-Snow (ROS) environment of the Pacific Northwest region, we explore the linkage between environmental control and the sensitivity of peakflow response to harvesting effects. Compared to previous paired watershed studies in ROS environment, we employed an experimental design of Frequency Pairing to isolate the effects of disturbances on systems' response. In contrary, the aspect of changing frequency distributions is not commonly invoked in previous literatures on the topic of forests and floods. Our results show how harvesting can dramatically increase the magnitude of all peakflows on record and how such effects can increase with increasing return periods, as a consequence of substantial increases to the mean and variance of the peakflow frequency distribution. Most critically, peakflows with return period larger than 10 years can increase in frequency, where the larger the peakflow event the more frequent it may become. The sensitivity of the upper tail of the frequency distribution of peakflows was found to be linked to the physiographic and climatic characteristics via a unifying synchronization / desynchronization spatial scaling mechanism that controls the generation of rain-on-snow runoff. This new physically-based stochastic hydrology understanding on the response of watersheds in ROS environments runs counter the deterministic prevailing wisdom of forest hydrology, which presumes a limited and diminishing role of forest cover as the magnitude of the peakflow event increases. By demonstrating the need for invoking the dimension of frequency in the understanding and prediction of the effects of harvesting on peakflows, findings from this study suggested that pure deterministic hypotheses and experimental designs that solely focusing on the changing magnitude of peakflows have been misguiding forest hydrology research for over a century

  15. Changes in photosynthesis and leaf characteristics with tree height in five dipterocarp species in a tropical rain forest.

    Science.gov (United States)

    Kenzo, Tanaka; Ichie, Tomoaki; Watanabe, Yoko; Yoneda, Reiji; Ninomiya, Ikuo; Koike, Takayoshi

    2006-07-01

    Variations in leaf photosynthetic, morphological and biochemical properties with increasing plant height from seedlings to emergent trees were investigated in five dipterocarp species in a Malaysian tropical rain forest. Canopy openness increased significantly with tree height. Photosynthetic properties, such as photosynthetic capacity at light saturation, light compensation point, maximum rate of carboxylation and maximum rate of photosynthetic electron transport, all increased significantly with tree height. Leaf morphological and biochemical traits, such as leaf mass per area, palisade layer thickness, nitrogen concentration per unit area, chlorophyll concentration per unit dry mass and chlorophyll to nitrogen ratio, also changed significantly with tree height. Leaf properties had simple and significant relationships with tree height, with few intra- and interspecies differences. Our results therefore suggest that the photosynthetic capacity of dipterocarp trees depends on tree height, and that the trees adapt to the light environment by adjusting their leaf morphological and biochemical properties. These results should aid in developing models that can accurately estimate carbon dioxide flux and biomass production in tropical rain forests.

  16. Isolation, diversity, and antimicrobial activity of rare actinobacteria from medicinal plants of tropical rain forests in Xishuangbanna, China.

    Science.gov (United States)

    Qin, Sheng; Li, Jie; Chen, Hua-Hong; Zhao, Guo-Zhen; Zhu, Wen-Yong; Jiang, Cheng-Lin; Xu, Li-Hua; Li, Wen-Jun

    2009-10-01

    Endophytic actinobacteria are relatively unexplored as potential sources of novel species and novel natural products for medical and commercial exploitation. Xishuangbanna is recognized throughout the world for its diverse flora, especially the rain forest plants, many of which have indigenous pharmaceutical histories. However, little is known about the endophytic actinobacteria of this tropical area. In this work, we studied the diversity of actinobacteria isolated from medicinal plants collected from tropical rain forests in Xishuangbanna. By the use of different selective isolation media and methods, a total of 2,174 actinobacteria were isolated. Forty-six isolates were selected on the basis of their morphologies on different media and were further characterized by 16S rRNA gene sequencing. The results showed an unexpected level of diversity, with 32 different genera. To our knowledge, this is the first report describing the isolation of Saccharopolyspora, Dietzia, Blastococcus, Dactylosporangium, Promicromonospora, Oerskovia, Actinocorallia, and Jiangella species from endophytic environments. At least 19 isolates are considered novel taxa by our current research. In addition, all 46 isolates were tested for antimicrobial activity and were screened for the presence of genes encoding polyketide synthetases and nonribosomal peptide synthetases. The results confirm that the medicinal plants of Xishuangbanna represent an extremely rich reservoir for the isolation of a significant diversity of actinobacteria, including novel species, that are potential sources for the discovery of biologically active compounds.

  17. Effects of air pollution and simulated acid rain on the ground vegetation of coniferous forests

    International Nuclear Information System (INIS)

    Rodenkirchen, H.

    1993-01-01

    Descriptive and experimental studies on the ground vegetation of coniferous forests in Bavaria indicated the following phenomena: a. In N-limited pine forests recent eutrophication effects occur. b. The structure of the moss layer in coniferous forests sensitively reacts to very acid throughfall water (pH [de

  18. Complex Spatial Structure in a Population of Didymopanax pittieri, A Tree of Wind-Exposed Lower Montane Rain Forest

    Science.gov (United States)

    Lawton, Robert M.; Lawton, Robert O.

    2010-01-01

    Didymopanax pittieri is a common shade-intolerant tree colonizing treefall gaps in the elfin forests on windswept ridgecrests in the lower montane rain forests of the Cordillera de Tilarain, Costa Rica. All D. pittieri taller than > 0.5 m in a 5.2-ha elfin forested portion of a gridded study watershed in the Monteverde Cloud Forest Preserve were located, mapped, and measured. This local population of D. pittieri is spatially inhomogeneous, in that density increases with increasing wind exposure; D. pittieri are more abundant near ridge crests than lower on windward slopes. The important and ubiquitous phenomenon of spatial inhomogeneity in population density is addressed and corrected for in spatial analyses by the application of the inhomogeneous version of Ripley's K. The spatial patterns of four size classes of D. pittieri ( 20 cm dbh) were investigated. Within the large-scale trend in density driven by wind exposure, D. pittieri saplings are clumped at the scale of treefall gaps and at the scale of patches of aggregated gaps. D. pittieri 5-10 cm dbh are randomly distributed, apparently due to competitive thinning of sapling clumps during the early stages of gap-phase regeneration. D. pittieri larger than 10 cm dbh are overdispersed at a scale larger than that of patches of gaps. Natural disturbance can influence the distribution of shade intolerant tree populations at several different spatial scales, and can have discordant effects at different life history stages.

  19. Variations in dung beetles assemblages (Coleoptera: Scarabaeidae within two rain forest habitats in French Guiana

    Directory of Open Access Journals (Sweden)

    François Feer

    2013-06-01

    Full Text Available The structure of dung beetle communities inhabiting tropical forests are known to be sensitive to many kinds of environmental changes such as microclimate related to vegetation structure. I examined Scarabaeinae assemblages in two sites of undisturbed high forest and two sites of low forest forming a transitional zone with the open habitat of an inselberg in French Guiana. Sampling was made with pitfall and flight interception traps during 2003 and 2004. The driest and warmest conditions characterized the low forest sites. Across two years we obtained 2 927 individuals from 61 species with pitfall traps and 1 431 individuals from 85 species with flight interception traps. Greater species richness and abundance characterized all sites sampled with pitfall traps during 2003 more than 2004. In 2003 no differences were detected among sites by rarefaction analyses. In 2004 the species richest high forest site was significantly different from one of the low forest sites. For both years Clench model asymptotes for species richness were greater in high forest than in low forest sites. For both years, mean per-trap species richness, abundance and biomass among high forest sites were similar and higher than in low forest sites, especially where the lowest humidity and the highest temperature were recorded. Within the two low forest sites, species richness and abundance recorded during the second year, decreased with distance to edge. Different dominant roller species characterized the pitfall samples in one site of low forest and in other sites. Small variations in microclimatic conditions correlated to canopy height and openness likely affected dung beetle assemblages but soil depth and the presence of large mammals providing dung resource may also play a significant role.

  20. Alternatives to deforestation: Steps toward sustainable use of the Amazon Rain Forest

    International Nuclear Information System (INIS)

    Anderson, A.B.

    1990-01-01

    The high rate of deforestation of the Brazilian Amazon over the past two decades has jeopardized genetic diversity, contributed to regional and global climate change, caused erosion and flooding, destroyed forest resources, spread disease, and increased poverty. This book presents a selection of papers from an international conference that explored alternatives to deforestation of tropical forests. The alternatives described include natural forest management, agroforestry systems, and forest reestablishment on degraded pastures. The book should be useful to scientists, regional planners, and the broad scientific audience

  1. Disturbance regimes, gap-demanding trees and seed mass related to tree height in warm temperate rain forests worldwide.

    Science.gov (United States)

    Grubb, Peter J; Bellingham, Peter J; Kohyama, Takashi S; Piper, Frida I; Valido, Alfredo

    2013-08-01

    For tropical lowland rain forests, Denslow (1987) hypothesized that in areas with large-scale disturbances tree species with a high demand for light make up a larger proportion of the flora; results of tests have been inconsistent. There has been no test for warm temperate rain forests (WTRFs), but they offer a promising testing ground because they differ widely in the extent of disturbance. WTRF is dominated by microphylls sensu Raunkiaer and has a simpler structure and range of physiognomy than tropical or subtropical rain forests. It occurs in six parts of the world: eastern Asia, New Zealand, Chile, South Africa, SE Australia and the Azores. On the Azores it has been mostly destroyed, so we studied instead the subtropical montane rain forest (STMRF) on the Canary Islands which also represents a relict of the kind of WTRF that once stretched across southern Eurasia. We sought to find whether in these six regions the proportion of tree species needing canopy gaps for establishment reflects the frequency and/or extent of canopy disturbance by wind, landslide, volcanic eruptions (lava flow and ash fall), flood or fire. We used standard floras and ecological accounts to draw up lists of core tree species commonly reaching 5 m height. We excluded species which are very rare, very localized in distribution, or confined to special habitats, e.g. coastal forests or rocky sites. We used published accounts and our own experience to classify species into three groups: (1) needing canopy gaps for establishment; (2) needing either light shade throughout or a canopy gap relatively soon (a few months or years) after establishment; and (3) variously more shade-tolerant. Group 1 species were divided according the kind of canopy opening needed: tree-fall gap, landslide, lava flow, flood or fire. Only some of the significant differences in proportion of Group 1 species were consistent with differences in the extent of disturbance; even in some of those cases other factors seem

  2. Erosion on very stony forest soil during phenomenal rain in Webster County, West Virginia

    Science.gov (United States)

    J. H. Patric; W. E., Jr. Kidd

    1982-01-01

    On July 15 and 16, 1979, at least 6 inches of rain fell in central West Virginia during 3 hours, a storm of return period longer than 1,000 years. More than 6 miles of logging roads were examined for evidences of soil erosion and sediment delivery to streams. Erosion was negligible on very stony soils where (a) logging roads were litter covered, (b) road grades were...

  3. Modelling rainfall interception by a lowland tropical rain forest in northeastern Puerto Rico.

    NARCIS (Netherlands)

    Schellekens, J.; Scatena, F.N.; Bruijnzeel, L.A.; Wickel, A.J.

    1999-01-01

    Recent surveys of tropical forest water use suggest that rainfall interception by the canopy is largest in wet maritime locations. To investigate the underlying processes at one such location-the Luquillo Experimental Forest in eastern Puerto Rico-66 days of detailed throughfall and above-canopy

  4. How much primary coastal temperate rain forest should society retain? Carbon uptake, recreation and other values

    NARCIS (Netherlands)

    Kooten, van G.C.; Bulte, E.H.

    2000-01-01

    In this study, average and marginal approaches for determining optimal preservation of primary forests on British Columbia's coast are compared. When the market values from timber, mushrooms, etc., and nonmarket benefits (e.g., carbon sink, preservation values) of preserving old-growth forests are

  5. Come Rain or Shine: A Whole School Approach to Forest School

    Science.gov (United States)

    Vandewalle, Martyn

    2010-01-01

    This article begins by describing a typical Forest School session that takes place in every class every week at The Wroxham School in Potters Bar. It goes on to outline a brief history of Forest School from its inception, its aims and ethos, and how it has been adapted for the ethos and needs of the children at Wroxham. The article also looks at…

  6. Air Pollution, Acid Rain, and the Future of Forests. Worldwatch Paper 58.

    Science.gov (United States)

    Postel, Sandra

    This book traces centuries of human use and abuse of forest ecosystems by discussing past decades of intense burning, grazing, and timber cutting that added to the natural acidification of the soil. Air pollutants and acids generated by industrial activities worldwide are also considered. Many forests in Europe and North America now receive as…

  7. Avian studies and research opportunities in the Luquillo Experimental Forest: a tropical rain forest in Puerto Rico

    Science.gov (United States)

    Joseph Wunderle, Jr; Wayne J. Arendt

    2011-01-01

    The Luquillo Experimental Forest (LEF) located on the Caribbean island of Puerto Rico has a rich history of ecological research, including a variety of avian studies, and is one of the most active ecological research sites in the Neotropics. The LEF spans an elevational range from 100 to 1075mover which five life zones and four forest types are found in a warm, humid...

  8. Case study: Rainfall partitioning across a natural-to-urban forest gradient during an extreme rain event

    Science.gov (United States)

    Akin, B. H.; Van Stan, J. T., II; Cote, J. F.; Jarvis, M. T.; Underwood, J.; Friesen, J.; Hildebrandt, A.; Maldonado, G.

    2017-12-01

    Trees' partitioning of rainfall is an important first process along the rainfall-to-runoff pathway that has economically significant influences on urban stormwater management. However, important knowledge gaps exist regarding (1) its role during extreme storms and (2) how this role changes as forest structure is altered by urbanization. Little research has been conducted on canopy rainfall partitioning during large, intense storms, likely because canopy water storage is rapidly overwhelmed (i.e., 1-3 mm) by short duration events exceeding, for example, 80 mm of rainfall. However, canopy structure controls more than just storage; it also affects the time for rain to drain to the surface (becoming throughfall) and the micrometeorological conditions that drive wet canopy evaporation. In fact, observations from an example extreme ( 100 mm with maximum 5-minute intensities exceeding 55 mm/h) storm across a urban-to-natural gradient in pine forests in southeast Georgia (USA), show that storm intensities were differentially dampened by 33% (tree row), 28% (forest fragment), and 17% (natural forests). In addition, maximum wet canopy evaporation rates were higher for the exposed tree row (0.18 mm/h) than for the partially-enclosed fragment canopy (0.14 mm/h) and the closed canopy natural forest site (0.11). This resulted in interception percentages decreasing from urban-to-natural stand structures (25% to 16%). A synoptic analysis of the extreme storm in this case study also shows that the mesoscale meteorological conditions that developed the heavy rainfall is expected to occur more often with projected climate changes.

  9. Dispersal limitation of Tillandsia species correlates with rain and host structure in a central Mexican tropical dry forest.

    Science.gov (United States)

    Victoriano-Romero, Elizabeth; Valencia-Díaz, Susana; Toledo-Hernández, Víctor Hugo; Flores-Palacios, Alejandro

    2017-01-01

    Seed dispersal permits the colonization of favorable habitats and generation of new populations, facilitating escape from habitats that are in decline. There is little experimental evidence of the factors that limit epiphyte dispersion towards their hosts. In a tropical dry forest in central Mexico, we monitored the phenology of dispersion of epiphyte species of the genus Tillandsia; we tested experimentally whether precipitation could cause failures in seed dispersal and whether seed capture differs among vertical strata and between host species with high (Bursera copallifera) and low (Conzattia multiflora) epiphyte loads. With the exception of one species that presents late dispersion and low abundance, all of the species disperse prior to the onset of the rainy season. However, early rains immobilize the seeds, affecting up to 24% of the fruits in species with late dispersion. We observed that Tillandsia seeds reach both Bursera and Conzattia hosts, but found that adherence to the host is 4-5 times higher in Bursera. Furthermore, seeds liberated from Bursera travel shorter distances and up to half may remain within the same crown, while the highest seed capture takes place in the upper strata of the trees. We conclude that dispersion of Tillandsia seeds is limited by early rains and by the capture of seeds within the trees where populations concentrate. This pattern of capture also helps to explain the high concentrations of epiphytes in certain hosts, while trees with few epiphytes can be simultaneously considered deficient receivers and efficient exporters of seeds.

  10. Dispersal limitation of Tillandsia species correlates with rain and host structure in a central Mexican tropical dry forest.

    Directory of Open Access Journals (Sweden)

    Elizabeth Victoriano-Romero

    Full Text Available Seed dispersal permits the colonization of favorable habitats and generation of new populations, facilitating escape from habitats that are in decline. There is little experimental evidence of the factors that limit epiphyte dispersion towards their hosts. In a tropical dry forest in central Mexico, we monitored the phenology of dispersion of epiphyte species of the genus Tillandsia; we tested experimentally whether precipitation could cause failures in seed dispersal and whether seed capture differs among vertical strata and between host species with high (Bursera copallifera and low (Conzattia multiflora epiphyte loads. With the exception of one species that presents late dispersion and low abundance, all of the species disperse prior to the onset of the rainy season. However, early rains immobilize the seeds, affecting up to 24% of the fruits in species with late dispersion. We observed that Tillandsia seeds reach both Bursera and Conzattia hosts, but found that adherence to the host is 4-5 times higher in Bursera. Furthermore, seeds liberated from Bursera travel shorter distances and up to half may remain within the same crown, while the highest seed capture takes place in the upper strata of the trees. We conclude that dispersion of Tillandsia seeds is limited by early rains and by the capture of seeds within the trees where populations concentrate. This pattern of capture also helps to explain the high concentrations of epiphytes in certain hosts, while trees with few epiphytes can be simultaneously considered deficient receivers and efficient exporters of seeds.

  11. Ethnobotanical study of medicinal plants in the environs of Tara-gedam and Amba remnant forests of Libo Kemkem District, northwest Ethiopia.

    Science.gov (United States)

    Chekole, Getnet; Asfaw, Zemede; Kelbessa, Ensermu

    2015-01-07

    Remnant forests found in areas that have long been converted to agricultural landscapes are refuges of wild useful plants; and societies inhabiting them are custodians of rich indigenous botanical knowledge. This study was undertaken to document the medicinal plants used by the people living in and around Tara-gedam and Amba remnant forests, northwestern Ethiopia, together with the associated ethnomedicinal knowledge. Data were collected from 105 informants through semi-structured interviews, guided field walk, market survey; and analyzed using standard ethnobotanical analytical tools including ranking and comparison. A total of 163 medicinal plant species in 145 genera and 67 families were recorded among which Zehneria scabra drew the highest community consensus. Seventy-one percent of the medicinal plants were those used for treating human ailments only, 21% for both human and livestock and 8% for livestock only. Asteraceae, with 14 species, had the highest number of medicinal plant species. The medicinal plants mainly (79.1%) belong to the shrub and herb categories and most of them were sourced from the wild habitats. Leaves and fresh plant materials were more frequently used for medicine preparation than other parts. Protected government and church forests as well as tree propagation in nurseries followed by planting them and local practices constitute the major forest conservation efforts that indirectly protect the medicinal plants in the area. Elders and healers knew more about the medicinal plants, their distribution, the local ethnomedicinal practices and knowledge transfer patterns. Though important for the local healthcare system and with potentials for modern drug discovery, both the plants and the knowledge pool are under threat. The diversity of medicinal plants and the associated indigenous knowledge of Tara-gedam and its environs are of a considerable value to the local community and beyond. There is, therefore, a need for conservation of the

  12. In tropical lowland rain forests monocots have tougher leaves than dicots, and include a new kind of tough leaf

    DEFF Research Database (Denmark)

    Dominy, N.J.; Grubb, P.J.; Jackson, R.V.

    2008-01-01

    -tolerant or gap-demanding species were considered. Conclusions: It is predicted that monocots will be found to experience lower rates of herbivory by invertebrates than dicots. The tough monocot leaves include both stiff leaves containing relatively little water at saturation (e.g. palms), and leaves which lack...... stiffness, are rich in water at saturation and roll readily during dry weather or even in bright sun around midday (e.g. gingers, heliconias and marants). Monocot leaves also show that it is possible for leaves to be notably tough throughout the expansion phase of development, something never recorded...... for dicots. The need to broaden the botanist's mental picture of a ‘tough leaf' is emphasized.   Key words: Dicots, fracture toughness, herbivory, leaves, monocots, punch strength, tropical rain forest  ...

  13. Organic aerosols from biomass burning in Amazonian rain forest and their impact onto the environment

    International Nuclear Information System (INIS)

    Cecinato, A.; Mabilia, R.; De Castro Vasconcellos, P.

    2001-01-01

    A field campaign performed in Southern Brazilian Amazonia in 1993 has proved that this region is subjected to fallout of particulated exhausts released by fires of forestal biomass. In fact, organic content of aerosols collected at urban sites located on the border of pluvial forest, about 50 km from fires, was similar to that of biomass burning exhausts. Aerosol composition is indicative of dolous origin of fires. However, organic contents seems to be influenced by two additional sources, i. e. motor vehicle and high vegetation emission. Chemical pattern of organic aerosols released by biomass burning of forest seems to promote occurrence of photochemical smog episodes in that region [it

  14. Predicting alpha diversity of African rain forests: models based on climate and satellite-derived data do not perform better than a purely spatial model

    NARCIS (Netherlands)

    Parmentier, I.; Harrigan, R.; Buermann, W.; Mitchard, E.T.A.; Saatchi, S.; Malhi, Y.; Bongers, F.; Hawthorne, W.D.; Leal, M.E.; Lewis, S.; Nusbaumer, L.; Sheil, D.; Sosef, M.S.M.; Bakayoko, A.; Chuyong, G.; Chatelain, C.; Comiskey, J.; Dauby, G.; Doucet, J.L.; Hardy, O.

    2011-01-01

    Aim Our aim was to evaluate the extent to which we can predict and map tree alpha diversity across broad spatial scales either by using climate and remote sensing data or by exploiting spatial autocorrelation patterns. Location Tropical rain forest, West Africa and Atlantic Central Africa. Methods

  15. Genetics and morphology of the genus Tritetrabdella (Hirudinea, Haemadipsidae) from the mountainous rain forests of Sabah, Borneo, reveal a new species with two new subspecies

    NARCIS (Netherlands)

    Kappes, H.

    2013-01-01

    Blood-feeding terrestrial leeches of the family Haemadipsidae are a notorious part of the invertebrate diversity in Asian and Australian rain forests. All hitherto published records of terrestrial leeches of Borneo belong to the genus Haemadipsa. Here, a second, poorly known haemadipsid genus is

  16. Spatial and temporal variation in soil CO2 efflux in an old-growth neotropical rain forest, LA Selva, Costa Rica

    Science.gov (United States)

    Luitgard Schwendenmann; Edzo Veldkamp; Tania Brenes; Joseph J. O' Brien; Jens Mackensen

    2003-01-01

    Our objectives were to quantify and compare soil CO2, efflux of two doininant soil types in an old-growth neotropical rain forest in the Atlantic zone of Costa Rica, and to evaluate the control of environmental Factors on CO2, release. We measured soil CO2 efflux from eight permanent soil chamhers on...

  17. Forest vegetation as a sink for atmospheric particulates: Quantitative studies in rain and dry deposition

    International Nuclear Information System (INIS)

    Russel, I.J.; Choquette, C.E.; Fang, S.; Dundulis, W.P.; Pao, A.A.; Pszenny, A.A.P.

    1981-01-01

    Radionuclides in the atmosphere are associated with nonradioactive air particulates and hence serve to trace the fluxes of air particulates to various surfaces. Natural and artificial radioactivities found in the atmosphere have been measured in vegetation for 10 years to elucidate some of the mechanisms of acquirement by forest trees of atmospheric particulates. Whole tree analysis, in conjunction with soil assay, have served to establish the fraction of the flux of radionuclides retained by above-ground tissues of a forest stand. Interpretation is facilitated because most radionuclides in the atmosphere are superficially acquired. Typically 5--20% of the total open field flux is retained by the forest canopy in a moderately rainy climate (120 cm/year). Short-lived daughters of radon give a dry deposition velocity of particulates in the Aitken size range of 0.03--0.05 cm/s, thus permitting an estimate of transient removal by forest canopies by dry deposition of this size fraction

  18. Rain forest nutrient cycling and productivity in response to large-scale litter manipulation.

    Science.gov (United States)

    Wood, Tana E; Lawrence, Deborah; Clark, Deborah A; Chazdon, Robin L

    2009-01-01

    Litter-induced pulses of nutrient availability could play an important role in the productivity and nutrient cycling of forested ecosystems, especially tropical forests. Tropical forests experience such pulses as a result of wet-dry seasonality and during major climatic events, such as strong El Niños. We hypothesized that (1) an increase in the quantity and quality of litter inputs would stimulate leaf litter production, woody growth, and leaf litter nutrient cycling, and (2) the timing and magnitude of this response would be influenced by soil fertility and forest age. To test these hypotheses in a Costa Rican wet tropical forest, we established a large-scale litter manipulation experiment in two secondary forest sites and four old-growth forest sites of differing soil fertility. In replicated plots at each site, leaves and twigs (forest floor. We analyzed leaf litter mass, [N] and [P], and N and P inputs for addition, removal, and control plots over a two-year period. We also evaluated basal area increment of trees in removal and addition plots. There was no response of forest productivity or nutrient cycling to litter removal; however, litter addition significantly increased leaf litter production and N and P inputs 4-5 months following litter application. Litter production increased as much as 92%, and P and N inputs as much as 85% and 156%, respectively. In contrast, litter manipulation had no significant effect on woody growth. The increase in leaf litter production and N and P inputs were significantly positively related to the total P that was applied in litter form. Neither litter treatment nor forest type influenced the temporal pattern of any of the variables measured. Thus, environmental factors such as rainfall drive temporal variability in litter and nutrient inputs, while nutrient release from decomposing litter influences the magnitude. Seasonal or annual variation in leaf litter mass, such as occurs in strong El Niño events, could positively

  19. Tracing the Sources of Atmospheric Phosphorus Deposition to a Tropical Rain Forest in Panama Using Stable Oxygen Isotopes.

    Science.gov (United States)

    Gross, A; Turner, B L; Goren, T; Berry, A; Angert, A

    2016-02-02

    Atmospheric dust deposition can be a significant source of phosphorus (P) in some tropical forests, so information on the origins and solubility of atmospheric P is needed to understand and predict patterns of forest productivity under future climate scenarios. We characterized atmospheric dust P across a seasonal cycle in a tropical lowland rain forest on Barro Colorado Nature Monument (BCNM), Republic of Panama. We traced P sources by combining remote sensing imagery with the first measurements of stable oxygen isotopes in soluble inorganic phosphate (δ(18)OP) in dust. In addition, we measured soluble inorganic and organic P concentrations in fine (1 μm) aerosol fractions and used this data to estimate the contribution of P inputs from dust deposition to the forest P budget. Aerosol dry mass was greater in the dry season (December to April, 5.6-15.7 μg m(-3)) than the wet season (May to November, 3.1-7.1 μg m(-3)). In contrast, soluble P concentrations in the aerosols were lower in the dry season (980-1880 μg P g(-1)) than the wet season (1170-3380 μg P g(-1)). The δ(18)OP of dry-season aerosols resembled that of nearby forest soils (∼19.5‰), suggesting a local origin. In the wet season, when the Trans-Atlantic Saharan dust belt moves north close to Panama, the δ(18)OP of aerosols was considerably lower (∼15.5‰), suggesting a significant contribution of long-distance dust P transport. Using satellite retrieved aerosol optical depth (AOD) and the P concentrations in aerosols we sampled in periods when Saharan dust was evident we estimate that the monthly P input from long distance dust transport during the period with highest Saharan dust deposition is 88 ± 31 g P ha(-1) month(-1), equivalent to between 10 and 29% of the P in monthly litter fall in nearby forests. These findings have important implications for our understanding of modern nutrient budgets and the productivity of tropical forests in the region under future climate scenarios.

  20. Logging impacts on forest structure and seedling dynamics in a Prioria copaifera (Fabaceae) dominated tropical rain forest (Talamanca, Costa Rica).

    Science.gov (United States)

    Valverde-Barrantes, Oscar J; Rocha, Oscar J

    2014-03-01

    The factors that determine the existence of tropical forests dominated by a single species (monodominated forests) have been the subject of debate for a long time. It has been hypothesized that the low frequency of disturbances in monodominated forests and the tolerance to shade of the monodominant species are two important factors explaining the prolonged dominance of a single species. We determined the role of these two factors by examining the effects of logging activities on the floristic composition and seedling dynamics in a Prioria copaifera dominated forest in Southeastern Costa Rica. We determined the floristic composition for trees > or = 2.5cm DBH and the associated recruitment, survival and mortality of tree canopy seedlings in two sites logged two (L-02) and 12 years (L-12) prior to sampling and an unlogged forest (ULF). Our results showed that L-02 stands had lower species richness (25 species) than the L-12 and ULF stands (49 and 46 species, respectively). As expected, we found significant logging effects on the canopy structure of the altered forests, particularly when comparing the L-02 and the ULF stands. Seedling density was higher in ULF (0.96 seedlings/ m2) than in the L-02 and L-12 stands (0.322 and 0.466 seedlings/m2, respectively). However, seedling mortality was higher in the ULF stands (54%) than in the L-02 (26%) and L-12 (15%) stands. P. macroloba in L-02 was the only species with abundant regeneration under P. copaifera in L-02 stand, where it accounted for 35% of the seedlings. Despite the reduction in seedling abundance observed after logging, P. copaifera seems to maintain large seedling populations in these forests, suggesting that this species maintains its dominance after logging disturbances. Our findings challenge the hypothesis that the regeneration of monodominant species is not likely to occur under heavily disturbed canopy conditions.

  1. Logging impacts on forest structure and seedling dynamics in a Prioria copaifera (Fabaceae dominated tropical rain forest (Talamanca, Costa Rica

    Directory of Open Access Journals (Sweden)

    Oscar J. Valverde-Barrantes

    2014-03-01

    Full Text Available The factors that determine the existence of tropical forests dominated by a single species (monodominated forests have been the subject of debate for a long time. It has been hypothesized that the low frequency of disturbances in monodominated forests and the tolerance to shade of the monodominant species are two important factors explaining the prolonged dominance of a single species. We determined the role of these two factors by examining the effects of logging activities on the floristic composition and seedling dynamics in a Prioria copaifera dominated forest in Southeastern Costa Rica. We determined the floristic composition for trees ≥2.5cm DBH and the associated recruitment, survival and mortality of tree canopy seedlings in two sites logged two (L-02 and 12 years (L-12 prior to sampling and an unlogged forest (ULF. Our results showed that L-02 stands had lower species richness (25 species than the L-12 and ULF stands (49 and 46 species, respectively. As expected, we found significant logging effects on the canopy structure of the altered forests, particularly when comparing the L-02 and the ULF stands. Seedling density was higher in ULF (0.96 seedlings/m² than in the L-02and L-12 stands (0.322 and 0.466 seedlings/m², respectively. However, seedling mortality was higher in the ULF stands (54% than in the L-02 (26% and L-12 (15% stands. P. macroloba in L-02 was the only species with abundant regeneration under P. copaifera in L-02 stand, where it accounted for 35% of the seedlings. Despite the reduction in seedling abundance observed after logging, P. copaifera seems to maintain large seedling populations in these forests, suggesting that this species maintains its dominance after logging disturbances. Our findings challenge the hypothesis that the regeneration of monodominant species is not likely to occur under heavily disturbed canopy conditions. Rev. Biol. Trop. 62 (1: 347-357. Epub 2014 March 01.

  2. The influence of habitat structure on bird species composition in lowland malaysian rain forests.

    Science.gov (United States)

    Mansor, Mohammad Saiful; Sah, Shahrul Anuar Mohd

    2012-05-01

    Bird surveys were conducted in the Bukit Kepala Gajah limestone area in Lenggong, Perak from July 2010 to January 2011. The study area was divided into three zones: forest edge, forest intermediate and forest interior. A point-count distance sampling method was used in the bird surveys. The study recorded 7789 detections, representing 100 bird species belonging to 28 families. Pycnonotidae, Timaliidae and Nectariniidae were the dominant families overall and showed the highest number of observations recorded in the study area whereas Motacillidae showed the fewest observations. The bird species were grouped into three feeding guilds: insectivores, frugivores and others (omnivores, carnivores, nectarivores and granivores). The species richness of insectivorous birds differed significantly among the forest zones sampled (Kruskal-Wallis: α=0.05, H=10.979, d.f.=2, p=0.004), with more insectivorous birds occurring in the forest interior. No significant differences were found among the zones in the species richness of either the frugivore guild or the composite others guild.

  3. Upper canopy pollinators of Eucryphia cordifolia Cav., a tree of South American temperate rain forest

    Directory of Open Access Journals (Sweden)

    Cecilia Smith-Ramírez

    2016-05-01

    Full Text Available Ecological processes in the upper canopy of temperate forests have been seldom studied because of the limited accessibility. Here, we present the results of the first survey of the pollinator assemblage and the frequency of insect visits to flowers in the upper branches of ulmo, Eucryphia cordifolia Cav., an emergent 30-40 m-tall tree in rainforests of Chiloé Island, Chile. We compared these findings with a survey of flower visitors restricted to lower branches of E. cordifolia 1- in the forest understory, 2- in lower branches in an agroforestry area. We found 10 species of pollinators in canopy, and eight, 12 and 15 species in understory, depending of tree locations. The main pollinators of E. cordifolia in the upper canopy differed significantly from the pollinator assemblage recorded in lower tree branches. We conclude that the pollinator assemblages of the temperate forest canopy and interior are still unknown.

  4. Radionuclides fallout on lichens and mosses and their leaching by rain in a forest ecosystem

    International Nuclear Information System (INIS)

    Guillitte, Olivier; Kirchmann, Rene; Gelder, E. van; Hurtgen, Christian

    1990-01-01

    In the framework of the Belgian radioecological surveillance programme around nuclear power plants and of research into the impact of fallout from the nuclear accident of Chernobyl on the Ardennes forests, samples of lichens and mosses were collected and measured for radioactive content. It was observed that there is a larger variation between the samples of the same species than between various species but collected from the same ecological niche. The ecological half-life of radionuclides is also dependent on location of these organisms in the forest biotope. Some suggestions regarding the sampling standards are proposed. (author)

  5. Using IKONOS and Aerial Videography to Validate Landsat Land Cover Maps of Central African Tropical Rain Forests

    Science.gov (United States)

    Lin, T.; Laporte, N. T.

    2003-12-01

    Compared to the traditional validation methods, aerial videography is a relatively inexpensive and time-efficient approach to collect "field" data for validating satellite-derived land cover map over large areas. In particular, this approach is valuable in remote and inaccessible locations. In the Sangha Tri-National Park region of Central Africa, where road access is limited to industrial logging sites, we are using IKONOS imagery and aerial videography to assess the accuracy of Landsat-derived land cover maps. As part of a NASA Land Cover Land Use Change project (INFORMS) and in collaboration with the Wildlife Conservation Society in the Republic of Congo, over 1500km of aerial video transects were collected in the Spring of 2001. The use of MediaMapper software combined with a VMS 200 video mapping system enabled the collection of aerial transects to be registered with geographic locations from a Geographic Positioning System. Video frame were extracted, visually interpreted, and compared to land cover types mapped by Landsat. We addressed the limitations of accuracy assessment using aerial-base data and its potential for improving vegetation mapping in tropical rain forests. The results of the videography and IKONOS image analysis demonstrate the utility of very high resolution imagery for map validation and forest resource assessment.

  6. Pollen rain and pollen representation across a forest-páramo ecotone in northern Ecuador

    NARCIS (Netherlands)

    Moscol Olivera, M.; Duivenvoorden, J.F.; Hooghiemstra, H.

    2009-01-01

    Modern pollen spectra were studied in forest and páramo vegetation from the Guandera area, northern Ecuador. Pollen representation was estimated by comparing the presence of plant taxa from a recent vegetation survey with the pollen spectra in moss polsters and pollen traps. In total, 73 pollen taxa

  7. Four novel Talaromyces species isolated from leaf litter from Colombian Amazon rain forests

    DEFF Research Database (Denmark)

    Yilmaz, Neriman; López-Quintero, Carlos A.; Vasco-Palacios, Aída Marcela

    2016-01-01

    Various Talaromyces strains were isolated during a survey of fungi involved in leaf litter decomposition in tropical lowland forests in the Caquetá and Amacayacu areas of the Colombian Amazon. Four new Talaromyces species are described using a polyphasic approach, which includes phenotypic......). In addition to the new species, T. aculeatus and T. macrosporus were isolated during this study on leaf litter decomposition....

  8. Biomass from the Brazilian raining forest; Biomassa das florestas amazonicas brasileiras

    Energy Technology Data Exchange (ETDEWEB)

    Fearnside, Philip M [Instituto Nacional de Pesquisas da Amazonia (INPA), Manaus, AM (Brazil)

    1994-12-31

    This work summarizes the existing knowledge about biomass in the Brazilian area of the Amazon jungle and presents a calculation for the average total biomass in virgin forests. The results are presented. The results are higher than those presently accepted. The reasons for the discrepancy in the calculated and presently used value are presented and discussed 64 refs., 8 tabs.

  9. Effects of liming on forage availability and nutrient content in a forest impacted by acid rain.

    Directory of Open Access Journals (Sweden)

    Sarah E Pabian

    Full Text Available Acidic deposition and subsequent forest soil acidification and nutrient depletion can affect negatively the growth, health and nutrient content of vegetation, potentially limiting the availability and nutrient content of forage for white-tailed deer (Odocoileus virginianus and other forest herbivores. Liming is a mitigation technique that can be used to restore forest health in acidified areas, but little is known about how it affects the growth or nutrient content of deer forage. We examined the effects of dolomitic limestone application on the growth and chemical composition of understory plants in an acidified forest in central Pennsylvania, with a focus on vegetative groups included as white-tailed deer forage. We used a Before-After-Control-Impact study design with observations 1 year before liming and up to 5 years post-liming on 2 treated and 2 untreated 100-ha sites. Before liming, forage availability and several nutrients were below levels considered optimal for white-tailed deer, and many vegetative characteristics were related to soil chemistry. We observed a positive effect of liming on forb biomass, with a 2.7 fold increase on limed sites, but no biomass response in other vegetation groups. We observed positive effects of liming on calcium and magnesium content and negative effects on aluminum and manganese content of several plant groups. Responses to liming by forbs and plant nutrients show promise for improving vegetation health and forage quality and quantity for deer.

  10. Vegetation structure, logging damage and silviculture in a tropical rain forest in Suriname

    NARCIS (Netherlands)

    Jonkers, W.B.J.

    1987-01-01

    In the first publication in this series, a polycyclic forest management system was formulated, in which three silvicultural treatments (refinements) were scheduled in a cutting cycle of twenty years. This system, which is referred to as the Celos Silvicultural System, is developed further

  11. No strong evidence for increasing liana abundance in the Myristicaceae of a Neotropical aseasonal rain forest.

    Science.gov (United States)

    Smith, James R; Queenborough, Simon A; Alvia, Pablo; Romero-Saltos, Hugo; Valencia, Renato

    2017-02-01

    The "liana dominance hypothesis" posits that lianas are increasing in abundance in tropical forests, thereby potentially reducing tree biomass due to competitive interactions between trees and lianas. This scenario has implications not only for forest ecosystem function and species composition, but also climate change given the mass of carbon stored in tropical trees. In 2003 and 2013, all Myristicaceae trees in the 50-ha Yasuní Forest Dynamics Plot, Ecuador, were surveyed for liana presence and load in their crowns. We tested the hypothesis that the proportion of trees with lianas increased between 2003 and 2013 in line with the liana dominance hypothesis. Contrary to expectations, the total proportion of trees with lianas decreased from 35% to 32%, and when only trees ≥10 cm diameter at breast height were considered liana incidence increased 44-48%. Liana load was dynamic with a large proportion of trees losing or gaining lianas over the 10-yr period; large trees with intermediate liana loads increased in proportion at the expense of those with low and high loads. Lianas also impacted performance: trees with 26-75% crown cover by lianas in 2003 had reduced growth rates of 80% compared to of liana-free trees, and trees with >75% crown cover had 33% the growth rate and a log odds of mortality eight times that of liana-free trees. We suggest that the lack of strong support found for the liana dominance hypothesis is likely due to the aseasonal climate of Yasuní, which limits the competitive advantage lianas maintain over trees during dry seasons due to their efficient capture and use of water. We propose further research of long-term liana dynamics from aseasonal forests is required to determine the generality of the increasing liana dominance hypothesis in Neotropical forests. © 2016 by the Ecological Society of America.

  12. Mortality and recruitment of trees in a tropical rain forest of Choco (Colombia)

    International Nuclear Information System (INIS)

    Quinto M, Harley; Rengifo I, Reimer; Ramos P, Yan

    2009-01-01

    A Rates of mortality and recruitment of trees were calculated in a permanent research plot established in the tropical wet forest. The study was based on two measurements, one was done in 1998 and the other in 2005, in which were measured the diameter (DBH) of trees with DBH>10 cm and surveyed dead and recruited trees. We also determined the type of mortality, the mortality and exponential recruitment coefficient, the aboveground biomass (AB) and the mean life of the forest. In the first census 709 individuals were recorded and 710 in the second one. The mean annual mortality rate of trees was 1.39% and the exponential mortality coefficient was 1.41%; the most common types of mortality were uprooting and snags. Annual recruitment rate was 1.2% and the exponential rate of recruitment was 1.19%. Mean life of this forest was estimated in 58.6 years. The AB was of 237.31 t ha-1 in the year 1998, and in the 2005 was of 259.9 t ha-1. The recruited individuals presented AB of 5.08 t ha-1, and the dead of 17.72 t ha-1; the increment of AB in survivors was 30.97 t ha-1 average. Similarity of number of individuals between measurements, as well as in the other parameters evaluated, suggest a possible balance between mortality and recruitment of this forest. Based on the results of this study, we could no reject the hypothesis of dynamic equilibrium of this tropical wet forest.

  13. Effect of aluminium on dissolved organic matter mineralization in an allophanic and kaolinitic temperate rain forest soil

    Science.gov (United States)

    Merino, Carolina; Matus, Francisco; Fontaine, Sebastien

    2016-04-01

    Aluminium (Al) and it influence on the mineralization of dissolved organic matter (DOM) and thus on carbon (C) sequestration in forest soils is poorly understood. We hypothesized that an addition of Al to the soil solution beyond a molar Al:C ratio of 0.1, induces precipitation of the organic matter which leads to an excess Al in the soil solution causing an inhibitory effect for growing microorganisms. We investigated the effect of Al concentrations for the potential of C biodegradation at different Al:C ratios from DOM and Ah mineral soil horizons from two temperate rain forest soils from southern Chile. Dissolved organic matter and surface mineral horizons were incubated with initial molar Al:C ratio from 0.08 to 1.38 found under at field conditions. Mineralization was quantified by measurement of C-CO2 evolved during 15 days. Increasing the initial Al:C ratio > 0.12, led to a considerable reduction in mineralization (up to 70%). For Al:C ratio biodegradation of DOM and thus an increased in the C sequestration in mineral soils with molar Al:C ratio > 0.12. The observed DOM losses in the stream water of pristine southern forests can be explained by increasing the bioavailability of organic C for Al:C ratio < 0.12. Aluminium concentration had a marked effect at the spectral ART-FTIR bands assigned to cellulose-like and aromatic compounds in Ah mineral soil, diminishing the mineralization. The present results were also confirmed by the Al fluorescence using a confocal microscopy.

  14. Carbon budget of Nyungwe Tropical Montane Rain Forest in Central Africa

    Science.gov (United States)

    Nyirambangutse, B.; Zibera, E.; Uwizeye, F. K.; Hansson, L.; Nsabimana, D.; Pleijel, H.; Uddling, J.; Wallin, G.

    2015-12-01

    African tropical rainforests host rich biodiversity and play many roles at different scales such as local, regional and global, in the functioning of the earth system. Despite that the African tropical forests are the world's second largest, it has been neglected in terms of understanding the storage and fluxes of carbon and other nutrients. The question of whether this biome is a net sink or source of atmospheric CO2 is still not answered, and little is known concerning the climate change response. Tropical montane forests are even more poorly sampled compared with their importance. Deeper understanding of these ecosystems is required to provide insights on how they might react under global change. To answer questions related to these issues for African tropical montane forests, 15 permanent 0.5 ha plots were established in 2011 in Nyungwe tropical montane rainforest gazetted as a National Park to protect its extensive floral and faunal diversity. The plots are arranged along an east-westerly transect and includes both primary and secondary forest communities. The study is connected to the global ecosystem monitoring network (GEM, http://gem.tropicalforests.ox.ac.uk/). The aim is to characterize spatial and temporal heterogeneity of carbon and nutrient dynamics processes. The role of microclimate, topography, human disturbances, and plant species to the variability of these pools and processes will be explored. We compare stocks and fluxes of carbon and nutrients of the secondary and primary forest communities. The carbon stock are determined by an inventory of height and diameter at breast height (dbh) of all trees with a dbh above 5 cm, wood density, biomass of understory vegetation, leaf area index, standing and fallen dead wood, fine root biomass and organic content of various soil layers (litter, organic and mineral soil down to 45 cm depth). The carbon fluxes are determined by measurements of photosynthesis and respiration of leaves, above and below ground

  15. Fine-Root Production in an Amazon Rain Forest: Deep Roots are an Important Component of Net Primary Productivity

    Science.gov (United States)

    Norby, R.; Cordeiro, A. L.; Oblitas, E.; Valverde-Barrantes, O.; Quesada, C. A.

    2017-12-01

    Fine-root production is a significant component of net primary production (NPP), but it is the most difficult of the major components to measure. Data on fine-root production are especially sparse from tropical forests, and therefore the estimates of tropical forest NPP may not be accurate. Many estimates of fine-root production are based on observations in the top 15 or 30 cm of soil, with the implicit assumption that this approach will capture most of the root distribution. We measured fine-root production in a 30-m tall, old-growth, terra firme rain forest near Manaus, Brazil, which is the site for a free-air CO2 enrichment (FACE) experiment. Ten minirhizotrons were installed at a 45 degree angle to a depth of 1.1 meters; the tubes were installed 2 years before any measurements were made to allow the root systems to recover from disturbance. Images were collected biweekly, and measurements of root length per area of minirhizotron window were scaled up to grams of root per unit land area. Scaling up minirhizotron measurments is problematic, but our estimate of fine-root standing crop in the top 15 cm of soil (281 ± 37 g dry matter m-2) compares well with a direct measurement of fine roots in two nearby 15-cm soil cores (290 ± 37 g m-2). Although the largest fraction of the fine-root standing crop was in the upper soil horizons, 44% of the fine-root mass was deeper than 30 cm, and 17% was deeper than 60 cm. Annual fine-root production was 934 ± 234 g dry matter m-2 (453 ± 113 g C m-2), which was 35% of estimated NPP of the forest stand (1281 g C m-2). A previous estimate of NPP of the forest at this site was smaller (1010 g m-2), but that estimate relied on fine-root production measured elsewhere and only in the top 10 or 30 cm of soil; fine roots accounted for 21% of NPP in that analysis. Extending root observations deeper into the soil will improve estimates of the contribution of fine-root production to NPP, which will in turn improve estimates of ecosystem

  16. Use and management of the natural resources of the Colombian Amazon rain forest: a biological approach

    Directory of Open Access Journals (Sweden)

    Angela Yaneth Landínez Torres

    2013-12-01

    Full Text Available This study analyzes the main features associated with biological use practices and management of forest resources in the Colombian Amazon. The theoretical cut proposal contrasts biological level, the forms of appropriation of forest resources in indigenous and urban contexts depending on the importance that such activity involves the establishment of management strategies biodiversity in Colombia. In this way, provides an integrative perspective that will address conflict situations considering environmental factors not only biological but cultural in various scenarios , to give sustenance to the decisions made and provide a reasonable treatment that enables the implementation of environmental regulation mechanisms in especially in areas such as strategic biological Colombian Amazon. Finally, reflect on the importance of facilitating the functional analysis of the connections and interrelationships of ecosystem components, including human communities, sketching involving both biological and social guidelines for sustainable use of biodiversity.

  17. Topographic and spatial controls of palm species distributions in a montane rain forest, southern Ecuador

    DEFF Research Database (Denmark)

    Svenning, J.-C.; Harlev, D.; Sørensen, M.M.

    2009-01-01

    The northern Andes harbour a flora that is as species-rich or even richer than the 18-times larger lowland Amazon basin. Gaining an understanding of how the high species richness of the Andean region is generated and maintained is therefore of particular interest. Environmental sorting due......). Mantel tests and indicator species analysis showed that both topography and spatial location imposed strong controls on palm species distributions at the study site. Our results suggest that species distributions in the studied montane forest landscape were partly determined by the species' habitat...... distributions at the study site. Other factors must also be involved, notably wind-exposure and hydrology, as discussed for lowland palm communities. Our results show that to understand plant community assembly in the tropical montane forests of the Andes it is too simple to focus just on environmental sorting...

  18. Variation in pH Optima of Hydrolytic Enzyme Activities in Tropical Rain Forest Soils ▿

    OpenAIRE

    Turner, Benjamin L.

    2010-01-01

    Extracellular enzymes synthesized by soil microbes play a central role in the biogeochemical cycling of nutrients in the environment. The pH optima of eight hydrolytic enzymes involved in the cycles of carbon, nitrogen, phosphorus, and sulfur, were assessed in a series of tropical forest soils of contrasting pH values from the Republic of Panama. Assays were conducted using 4-methylumbelliferone-linked fluorogenic substrates in modified universal buffer. Optimum pH values differed markedly am...

  19. Diversity of orchids epiphytes, in a tropical rain forest (bh-T) of Department Choco, Colombia

    International Nuclear Information System (INIS)

    Mejia Rosero, Heidy; Pino Benitez, Nayive

    2010-01-01

    The diversity of epiphytes orchids in a tropical humid forest of the municipality of Tutunendo (Quibdo) was evaluated. According to its level of intervention, it was established three zones in the forest: low (300 m 2 ), medium (400 m 2 ) and highly intervened (300 m 2 ); 66 forofitos with a DAP ≥ 20 cm were recorded, in which orchids guests were sampled giving a total record of 1348 specimens, distributed in 49 species and 20 genera. In terms of number of species, the most representative genera were Maxillaria (11) and Dichaea (5). According to the Shannon-Weiner index a high diversity of epiphytes orchids can be observed in the area of study (H'= 3.30). Regarding to areas according to the level of intervention, the low and medium intervened forest showed the highest diversity, however, the highly intervened, where tomb cultivation, sowing logging is constant, presented the lowest results. According to the Kruskal-Wallis test, these areas showed significant differences (P <0.05) in terms of richness and abundance of recorded species. Evidently, the high diversity of this group of plants may be due to certain climatic conditions (precipitation, humidity and light intensity), facilitating their establishment in the area.

  20. Direct damage to vegetation caused by acid rain and polluted cloud: definition of critical levels for forest trees.

    Science.gov (United States)

    Cape, J N

    1993-01-01

    The concept of critical levels was developed in order to define short-term and long-term average concentrations of gaseous pollutants above which plants may be damaged. Although the usual way in which pollutants in precipitation (wet deposition) influence vegetation is by affecting soil processes, plant foliage exposed to fog and cloud, which often contain much greater concentrations of pollutant ions than rain, may be damaged directly. The idea of a critical level has been extended to define concentrations of pollutants in wet deposition above which direct damage to plants is likely. Concentrations of acidity and sulphate measured in mountain and coastal cloud are summarised. Vegetation at risk of injury is identified as montane forest growing close to the cloud base, where ion concentrations are highest. The direct effects of acidic precipitation on trees are reviewed, based on experimental exposure of plants to simulated acidic rain, fog or mist. Although most experiments have reported results in terms of pH (H(+) concentration), the accompanying anion is important, with sulphate being more damaging than nitrate. Both conifers and broadleaved tree seedlings showing subtle changes in the structural characteristics of leaf surfaces after exposure to mist or rain at or about pH 3.5, or sulphate concentration of 150 micromol litre(-1). Visible lesions on leaf surfaces occur at around pH 3 (500 micromol litre(-1) sulphate), broadleaved species tending to be more sensitive than conifers. Effects on photosynthesis and water relations, and interactions with other stresses (e.g. frost), have usually been observed only for treatments which have also caused visible injury to the leaf surface. Few experiments on the direct effects of polluted cloud have been conducted under field conditions with mature trees, which unlike seedlings in controlled conditions, may suffer a growth reduction in the absence of visible injury. Although leaching of cations (Ca(2+), Mg(2+), K(+)) is

  1. Analysis of floristic similarity between forest remnants from the upper Paraná river floodplain, Brazil - doi: 10.4025/actascibiolsci.v34i3.8500

    Directory of Open Access Journals (Sweden)

    Simone Rodrigues Slusarski

    2012-06-01

    Full Text Available The vegetation from the upper Paraná river floodplain is a fragment of Seasonal Semideciduous Forest (SSF that presents fields, lowlands and extensive areas of pasture along with forest formations. Aiming to accomplish analyses of floristic similarity between riparian forests remnants in this floodplain, an analysis using nine surveys was performed, four on the right bank, two on the left bank and three at an island, including tree species. Sørensen’s (ISs and Jaccard’s (ISj similarity coefficients were calculated, and a Correspondence Analysis (CA was applied to a matrix of presence and absence of species. Thirty-seven families, 80 genera and 110 species were recorded. Among the species, 5.5% were generalist, while 29.1% were exclusive to one survey. The values of ISs and ISj ranged from 31 to 78.4%, and 31 to 64.5%, respectively. The CA grouped the surveys in the right and left banks and the island; the species with the highest positive correlation on axis 1 were the most common in the surveys on the left bank. The obtained results evidenced that floristic surveys constitute important indicatives for evaluations of the vegetation distribution in the floodplain. 

  2. Calculation of Individual Tree Water Use in a Bornean Tropical Rain Forest Using Individual-Based Dynamic Vegetation Model SEIB-DGVM

    Science.gov (United States)

    Nakai, T.; Kumagai, T.; Saito, T.; Matsumoto, K.; Kume, T.; Nakagawa, M.; Sato, H.

    2015-12-01

    Bornean tropical rain forests are among the moistest biomes of the world with abundant rainfall throughout the year, and considered to be vulnerable to a change in the rainfall regime; e.g., high tree mortality was reported in such forests induced by a severe drought associated with the ENSO event in 1997-1998. In order to assess the effect (risk) of future climate change on eco-hydrology in such tropical rain forests, it is important to understand the water use of trees individually, because the vulnerability or mortality of trees against climate change can depend on the size of trees. Therefore, we refined the Spatially Explicit Individual-Based Dynamic Global Vegetation Model (SEIB-DGVM) so that the transpiration and its control by stomata are calculated for each individual tree. By using this model, we simulated the transpiration of each tree and its DBH-size dependency, and successfully reproduced the measured data of sap flow of trees and eddy covariance flux data obtained in a Bornean lowland tropical rain forest in Lambir Hills National Park, Sarawak, Malaysia.

  3. Nest spacing and architecture, and swarming of males of Dinoponera quadriceps (Hymenoptera, Formicidae in a remnant of the Atlantic Forest in Northeast Brazil

    Directory of Open Access Journals (Sweden)

    A. Vasconcellos

    Full Text Available Dinoponera quadriceps is a queenless neotropical ponerinae ant. Nest spacing and abundance were investigated in a remnant of the Atlantic forest in Northeast Brazil. Males were captured with a light trap between August 1994 and July 1996. Nest density varied from 15 to 40 ha-1. An overdispersion of nests suggests that the intraspecific competition may be an important factor regulating their spatial arrangement. Territory size was correlated with worker population size of the colonies. The nests had up to 16 chambers, with variations in their architecture closely related to habitat diversification. Populations varied from 12 to 97 adult workers per nest, with a mean density of 1,618 workers ha-1 and a live biomass of 461 g ha-1 (n = 13 nests. Males swarm continually throughout almost all months of the year, suggesting that production and swarming are more influenced by mechanisms that regulate the sexual activity of workers than by climatic factors.

  4. Modelling rainfall interception by a lowland tropical rain forest in northeastern Puerto Rico

    Science.gov (United States)

    Schellekens, J.; Scatena, F. N.; Bruijnzeel, L. A.; Wickel, A. J.

    1999-12-01

    Recent surveys of tropical forest water use suggest that rainfall interception by the canopy is largest in wet maritime locations. To investigate the underlying processes at one such location—the Luquillo Experimental Forest in eastern Puerto Rico—66 days of detailed throughfall and above-canopy climatic data were collected in 1996 and analysed using the Rutter and Gash models of rainfall interception. Throughfall occurred on 80% of the days distributed over 80 rainfall events. Measured interception loss was 50% of gross precipitation. When Penman-Monteith based estimates for the wet canopy evaporation rate (0.11 mm h -1 on average) and a canopy storage of 1.15 mm were used, both models severely underestimated measured interception loss. A detailed analysis of four storms using the Rutter model showed that optimizing the model for the wet canopy evaporation component yielded much better results than increasing the canopy storage capacity. However, the Rutter model failed to properly estimate throughfall amounts during an exceptionally large event. The analytical model, on the other hand, was capable of representing interception during the extreme event, but once again optimizing wet canopy evaporation rates produced a much better fit than optimizing the canopy storage capacity. As such, the present results support the idea that it is primarily a high rate of evaporation from a wet canopy that is responsible for the observed high interception losses.

  5. Comparison of infrared canopy temperature in a rubber plantation and tropical rain forest

    Science.gov (United States)

    Song, Qing-Hai; Deng, Yun; Zhang, Yi-Ping; Deng, Xiao-Bao; Lin, You-Xing; Zhou, Li-Guo; Fei, Xue-Hai; Sha, Li-Qing; Liu, Yun-Tong; Zhou, Wen-Jun; Gao, Jin-Bo

    2017-10-01

    Canopy temperature is a result of the canopy energy balance and is driven by climate conditions, plant architecture, and plant-controlled transpiration. Here, we evaluated canopy temperature in a rubber plantation (RP) and tropical rainforest (TR) in Xishuangbanna, southwestern China. An infrared temperature sensor was installed at each site to measure canopy temperature. In the dry season, the maximum differences (Tc - Ta) between canopy temperature (Tc) and air temperature (Ta) in the RP and TR were 2.6 and 0.1 K, respectively. In the rainy season, the maximum (Tc - Ta) values in the RP and TR were 1.0 and -1.1 K, respectively. There were consistent differences between the two forests, with the RP having higher (Tc - Ta) than the TR throughout the entire year. Infrared measurements of Tc can be used to calculate canopy stomatal conductance in both forests. The difference in (Tc - Ta) at three gc levels with increasing direct radiation in the RP was larger than in the TR, indicating that change in (Tc - Ta) in the RP was relatively sensitive to the degree of stomatal closure.

  6. Distribution of bioluminescent fungi across old-growth and secondary tropical rain forest in Costa Rica

    Directory of Open Access Journals (Sweden)

    Carolina Seas-Carvajal

    2013-06-01

    Full Text Available Most research on bioluminescent fungi is concentrated on their taxonomic relationships, while the basics of their natural history and ecological relationships are poorly understood. In this study, we compared the distribution of bioluminescent fungi between old-growth and secondary forest as related to four different soil types at the tropical rainforest of La Selva Biological Station in Costa Rica. The study was conducted during the wet season of 2009. Bioluminescent fungi were sought following eight different transects distributed evenly in old-growth and secondary forests across four different soil types, covering an area of 9 420m². We found fungi in four different substrates: litter, fallen branches, dead trunks, and roots, for a total of 61 samples. Correspondence analysis showed that the occurrence of fungi and soil types were related (inertia=0.21, p=0.071. We found a significant relationship between the presence of fungi and the distribution of soil types (X²=18.89, df=9, p=0.026. We found only three samples with fruiting bodies, two of which had Mycena and the other had one fungus of the order Xylariales (possibly Hypoxylon sp., Kretzschmariella sp., Xylaria sp.. Future work will concentrate on exploring other aspects of their ecology, such as their dispersal and substrate preference. This information will facilitate field identification and will foster more research on the distribution, seasonality, reproductive phenology and ecological requirements of this group of Fungi.

  7. Importance of terrestrial arthropods as subsidies in lowland Neotropical rain forest stream ecosystems

    Science.gov (United States)

    Small, Gaston E.; Torres, Pedro J.; Schwizer, Lauren M.; Duff, John H.; Pringle, Catherine M.

    2013-01-01

    The importance of terrestrial arthropods has been documented in temperate stream ecosystems, but little is known about the magnitude of these inputs in tropical streams. Terrestrial arthropods falling from the canopy of tropical forests may be an important subsidy to tropical stream food webs and could also represent an important flux of nitrogen (N) and phosphorus (P) in nutrient-poor headwater streams. We quantified input rates of terrestrial insects in eight streams draining lowland tropical wet forest in Costa Rica. In two focal headwater streams, we also measured capture efficiency by the fish assemblage and quantified terrestrially derived N- and P-excretion relative to stream nutrient uptake rates. Average input rates of terrestrial insects ranged from 5 to 41 mg dry mass/m2/d, exceeding previous measurements of aquatic invertebrate secondary production in these study streams, and were relatively consistent year-round, in contrast to values reported in temperate streams. Terrestrial insects accounted for half of the diet of the dominant fish species, Priapicthys annectens. Although terrestrially derived fish excretion was found to be a small flux relative to measured nutrient uptake rates in the focal streams, the efficient capture and processing of terrestrial arthropods by fish made these nutrients available to the local stream ecosystem. This aquatic-terrestrial linkage is likely being decoupled by deforestation in many tropical regions, with largely unknown but potentially important ecological consequences.

  8. An instrument design and sample strategy for measuring soil respiration in the coastal temperate rain forest

    Science.gov (United States)

    Nay, S. M.; D'Amore, D. V.

    2009-12-01

    The coastal temperate rainforest (CTR) along the northwest coast of North America is a large and complex mosaic of forests and wetlands located on an undulating terrain ranging from sea level to thousands of meters in elevation. This biome stores a dynamic portion of the total carbon stock of North America. The fate of the terrestrial carbon stock is of concern due to the potential for mobilization and export of this store to both the atmosphere as carbon respiration flux and ocean as dissolved organic and inorganic carbon flux. Soil respiration is the largest export vector in the system and must be accurately measured to gain any comprehensive understanding of how carbon moves though this system. Suitable monitoring tools capable of measuring carbon fluxes at small spatial scales are essential for our understanding of carbon dynamics at larger spatial scales within this complex assemblage of ecosystems. We have adapted instrumentation and developed a sampling strategy for optimizing replication of soil respiration measurements to quantify differences among spatially complex landscape units of the CTR. We start with the design of the instrument to ease the technological, ergonomic and financial barriers that technicians encounter in monitoring the efflux of CO2 from the soil. Our sampling strategy optimizes the physical efforts of the field work and manages for the high variation of flux measurements encountered in this difficult environment of rough terrain, dense vegetation and wet climate. Our soil respirometer incorporates an infra-red gas analyzer (LiCor Inc. LI-820) and an 8300 cm3 soil respiration chamber; the device is durable, lightweight, easy to operate and can be built for under $5000 per unit. The modest unit price allows for a multiple unit fleet to be deployed and operated in an intensive field monitoring campaign. We use a large 346 cm2 collar to accommodate as much micro spatial variation as feasible and to facilitate repeated measures for tracking

  9. Effects of land clearing techniques and tillage systems on runoff and soil erosion in a tropical rain forest in Nigeria.

    Science.gov (United States)

    Ehigiator, O A; Anyata, B U

    2011-11-01

    This work reports runoff and soil loss from each of 14 sub-watersheds in a secondary rain forest in south-western Nigeria. The impact of methods of land clearing and post-clearing management on runoff and soil erosion under the secondary forest is evaluated. These data were acquired eighteen years after the deforestation of primary vegetation during the ' West bank' project of the International Institute for Tropical Agriculture (IITA). These data are presented separately for each season; however, statistical analyses for replicates were not conducted due to differences in their past management. Soil erosion was affected by land clearing and tillage methods. The maximum soil erosion was observed on sub-watersheds that were mechanically cleared with tree-pusher/root-rake attachments and tilled conventionally. A high rate of erosion was observed even when graded-channel terraces were constructed to minimize soil erosion. In general there was much less soil erosion on manually cleared than on mechanically cleared sub-watersheds (2.5 t ha(-1) yr(-1) versus 13.8 t ha(-1) yr(-1)) and from the application of no-tillage methods than from conventionally plowed areas (6.5 t ha(-1) yr(-1) versus 12.1 t ha(-1) yr(-1)). The data indicate that tillage methods and appropriate management of soils and crops play an important role in soil and water conservation and in decreasing the rate of decline of soil quality. Copyright © 2011 Elsevier Ltd. All rights reserved.

  10. Effects of land-use changes on evapotranspiration of tropical rain forest margin area in Central Sulawesi (Indonesia): Modelling study with a regional SVAT model

    DEFF Research Database (Denmark)

    Olchev, A.; Ibrom, Andreas; Priess, J.

    2008-01-01

    The impact of deforestation and land-use changes on evapotranspiration of mountainous tropical rain forest area in the northern part of the Lore-Lindu National Park (LLNP) in Central Sulawesi (Indonesia) was quantified using a regional process-based SVAT model "SVAT-Regio". Description...... of the areas covered by tropical rain forests, i.e. about 15%, and an increase of agricultural (coffee plantations, corn and rice fields) and urban areas. Moreover, the scenario assumes a small increase of grassland areas as well. The results of modelling experiments show that 15% deforestation of the study......, and lowest in sunny and dry days. (c) 2007 Elsevier B.V. All rights reserved....

  11. Controls over foliar N:P ratios in tropical rain forests.

    Science.gov (United States)

    Townsend, Alan R; Cleveland, Cory C; Asner, Gregory P; Bustamante, Mercedes M C

    2007-01-01

    Correlations between foliar nutrient concentrations and soil nutrient availability have been found in multiple ecosystems. These relationships have led to the use of foliar nutrients as an index of nutrient status and to the prediction of broadscale patterns in ecosystem processes. More recently, a growing interest in ecological stoichiometry has fueled multiple analyses of foliar nitrogen:phosphorus (N:P) ratios within and across ecosystems. These studies have observed that N:P values are generally elevated in tropical forests when compared to higher latitude ecosystems, adding weight to a common belief that tropical forests are generally N rich and P poor. However, while these broad generalizations may have merit, their simplicity masks the enormous environmental heterogeneity that exists within the tropics; such variation includes large ranges in soil fertility and climate, as well as the highest plant species diversity of any biome. Here we present original data on foliar N and P concentrations from 150 mature canopy tree species in Costa Rica and Brazil, and combine those data with a comprehensive new literature synthesis to explore the major sources of variation in foliar N:P values within the tropics. We found no relationship between N:P ratios and either latitude or mean annual precipitation within the tropics alone. There is, however, evidence of seasonal controls; in our Costa Rica sites, foliar N:P values differed by 25% between wet and dry seasons. The N:P ratios do vary with soil P availability and/or soil order, but there is substantial overlap across coarse divisions in soil type, and perhaps the most striking feature of the data set is variation at the species level. Taken as a whole, our results imply that the dominant influence on foliar N:P ratios in the tropics is species variability and that, unlike marine systems and perhaps many other terrestrial biomes, the N:P stoichiometry of tropical forests is not well constrained. Thus any use of N

  12. [Seasonal variation of soil respiration and its components in tropical rain forest and rubber plantation in Xishuangbanna, Yunnan].

    Science.gov (United States)

    Lu, Hua-Zheng; Sha, Li-Qing; Wang, Jun; Hu, Wen-Yan; Wu, Bing-Xia

    2009-10-01

    By using trenching method and infrared gas analyzer, this paper studied the seasonal variation of soil respiration (SR), including root respiration (RR) and heterotrophic respiration (HR), in tropical seasonal rain forest (RF) and rubber (Hevea brasiliensis) plantation (RP) in Xishuangbanna of Yunnan, China. The results showed that the SR and HR rates were significantly higher in RF than in RP (P dry-hot season > foggy season, but the RR rate was rainy season > foggy season > dry-hot season in RF, and foggy season > rainy season > dry-hot season in RP. The contribution of RR to SR in RF (29%) was much lower than that in RP (42%, P < 0.01), while the contribution of HR to SR was 71% in RF and 58% in RP. When the soil temperature at 5 cm depth varied from 12 degrees C to 32 degrees C, the Q10 values for SR, HR, and RR rates were higher in RF than in RP. HR had the highest Q10 value, while RR had the lowest one.

  13. Relating tree growth to rainfall in Bolivian rain forests: a test for six species using tree ring analysis.

    Science.gov (United States)

    Brienen, Roel J W; Zuidema, Pieter A

    2005-11-01

    Many tropical regions show one distinct dry season. Often, this seasonality induces cambial dormancy of trees, particularly if these belong to deciduous species. This will often lead to the formation of annual rings. The aim of this study was to determine whether tree species in the Bolivian Amazon region form annual rings and to study the influence of the total amount and seasonal distribution of rainfall on diameter growth. Ring widths were measured on stem discs of a total of 154 trees belonging to six rain forest species. By correlating ring width and monthly rainfall data we proved the annual character of the tree rings for four of our study species. For two other species the annual character was proved by counting rings on trees of known age and by radiocarbon dating. The results of the climate-growth analysis show a positive relationship between tree growth and rainfall in certain periods of the year, indicating that rainfall plays a major role in tree growth. Three species showed a strong relationship with rainfall at the beginning of the rainy season, while one species is most sensitive to the rainfall at the end of the previous growing season. These results clearly demonstrate that tree ring analysis can be successfully applied in the tropics and that it is a promising method for various research disciplines.

  14. A new species of small-eared shrew (Mammalia, Eulipotyphla, Cryptotis) from the Lacandona rain forest, Mexico

    Science.gov (United States)

    Guevara, Lázaro; Sánchez-Cordero, Víctor; León-Paniagua, Livia; Woodman, Neal

    2014-01-01

    The diversity and distribution of mammals in the American tropics remain incompletely known. We describe a new species of small-eared shrew (Soricidae, Cryptotis) from the Lacandona rain forest, Chiapas, southern Mexico. The new species is distinguished from other species of Cryptotis on the basis of a unique combination of pelage coloration, size, dental, cranial, postcranial, and external characters, and genetic distances. It appears most closely related to species in the Cryptotis nigrescens species group, which occurs from southern Mexico to montane regions of Colombia. This discovery is particularly remarkable because the new species is from a low-elevation habitat (approximately 90 m), whereas most shrews in the region are restricted to higher elevations, typically > 1,000 m. The only known locality for the new shrew is in one of the last areas in southern Mexico where relatively undisturbed tropical vegetation is still found. The type locality is protected by the Mexican government as part of the Yaxchilán Archaeological Site on the border between Mexico and Guatemala.

  15. Mast fruiting of large ectomycorrhizal African rain forest trees: importance of dry season intensity, and the resource-limitation hypothesis.

    Science.gov (United States)

    Newbery, David M; Chuyong, George B; Zimmermann, Lukas

    2006-01-01

    Mast fruiting is a distinctive reproductive trait in trees. This rain forest study, at a nutrient-poor site with a seasonal climate in tropical Africa, provides new insights into the causes of this mode of phenological patterning. At Korup, Cameroon, 150 trees of the large, ectomycorrhizal caesalp, Microberlinia bisulcata, were recorded almost monthly for leafing, flowering and fruiting during 1995-2000. The series was extended to 1988-2004 with less detailed data. Individual transitions in phenology were analysed. Masting occurred when the dry season before fruiting was drier, and the one before that was wetter, than average. Intervals between events were usually 2 or 3 yr. Masting was associated with early leaf exchange, followed by mass flowering, and was highly synchronous in the population. Trees at higher elevation showed more fruiting. Output declined between 1995 and 2000. Mast fruiting in M. bisulcata appears to be driven by climate variation and is regulated by internal tree processes. The resource-limitation hypothesis was supported. An 'alternative bearing' system seems to underlie masting. That ectomycorrhizal habit facilitates masting in trees is strongly implied.

  16. Plant Trait Dataset for Tree-Like Growth Forms Species of the Subtropical Atlantic Rain Forest in Brazil

    Directory of Open Access Journals (Sweden)

    Arthur Vinicius Rodrigues

    2018-05-01

    Full Text Available Plant functional traits have been incorporated in studies of vegetation ecology to better understand the mechanisms of ecological processes. For this reason, a global effort has been made to collect functional traits data for as many species as possible. In light of this, we identified the most common species of an area of 15,335 km2 inserted in the subtropical Atlantic Rain Forest in Southern Brazil. Then, we compiled functional trait information mostly from field samples, but also from herbarium and literature. The dataset presents traits of leaf, branch, maximum potential height, seed mass, and dispersion syndrome of 117 species, including trees, tree ferns, and palms. We also share images of anatomical features of branches used to measure wood traits. Data tables present mean trait values at individual and species level. Images of wood and stomatal features may be useful to assess other anatomical traits that were not covered in the data tables for the anatomical determination of species and/or for educational purposes.

  17. Effects of acid rain and liming on the enchytraeid fauna in forest soils

    International Nuclear Information System (INIS)

    Graefe, U.

    1989-01-01

    The development of the enchytraeid community has been observed in a Solling beech forest over a period of 11 years. Eight out of 18 formerly established species have disappeared in one decade. The connection to soil chemical changes due to atmospheric deposition is discussed. A comparison of adjoining beech and spruce stands revealed considerably lower species numbers under spruce. The community under beech is developing in the direction of the species community in the spruce stand. Liming affects changes in the dominance structure. Mesophilic species are favoured, acidophilic are repressed. In an oak-beech stand near Hamburg even the recolonization by previously absent species was observed. Liming experiments with 25, 50 and 100 dt CaCO 3 /ha showed decreasing total abundance of enchytraeids proportional to the amount of lime. Species number, diversity and evenness increased with lime treatments up to 50 dt/ha. (orig.)

  18. Persistence of long-distance, insect-mediated pollen movement for a tropical canopy tree species in remnant forest patches in an urban landscape.

    Science.gov (United States)

    Noreen, A M E; Niissalo, M A; Lum, S K Y; Webb, E L

    2016-12-01

    As deforestation and urbanization continue at rapid rates in tropical regions, urban forest patches are essential repositories of biodiversity. However, almost nothing is known about gene flow of forest-dependent tree species in urban landscapes. In this study, we investigated gene flow in the insect-pollinated, wind-dispersed tropical tree Koompassia malaccensis in and among three remnant forest patches in the urbanized landscape of Singapore. We genotyped the vast majority of adults (N=179) and a large number of recruits (N=2103) with 8 highly polymorphic microsatellite markers. Spatial genetic structure of the recruit and adult cohorts was significant, showing routine gene dispersal distances of ~100-400 m. Parentage analysis showed that 97% of recruits were within 100 m of their mother tree, and a high frequency of relatively short-distance pollen dispersal (median ~143-187 m). Despite routine seed and pollen dispersal distances of within a few hundred meters, interpatch gene flow occurred between all patches and was dominated by pollen movement: parentage analysis showed 76 pollen versus 2 seed interpatch dispersal events, and the seedling neighborhood model estimated ~1-6% seed immigration and ~21-46% pollen immigration rates, depending on patch. In addition, the smallest patch (containing five adult K. malaccensis trees) was entirely surrounded by >2.5 km of 'impervious' substrate, yet had the highest proportional pollen and seed immigration estimates of any patch. Hence, contrary to our hypothesis, insect-mediated gene flow persisted across an urban landscape, and several of our results also parallel key findings from insect-pollinated canopy trees sampled in mixed agricultural-forest landscapes.

  19. The Phlebotominae sand fly (Diptera: Psychodidae fauna of two Atlantic Rain Forest Reserves in the State of Rio de Janeiro, Brazil

    Directory of Open Access Journals (Sweden)

    Souza Nataly A

    2001-01-01

    Full Text Available During two consecutive years, studies on the sand fly fauna in Poço das Antas and Fazenda Bom Retiro, two Atlantic Rain Forest Reserves from the State of Rio de Janeiro, were performed using Shannon traps, CDC light traps and human bait collections. Eleven species were identified; Lutzomyia longipalpis, L. migonei, L. edwardsi, L. intermedia, L. whitmani, L. fischeri, L. shannoni, L. ayrozai, L. hirsuta, L. monticola and L. misionensis (first occurrence in the State of Rio de Janeiro. L. intermedia and L. whitmani were the predominant anthropophilic species around houses, while L. hirsuta predominated in the forest.

  20. Effects of simulated acid rain on soil respiration and its components in a subtropical mixed conifer and broadleaf forest in southern China.

    Science.gov (United States)

    Liang, Guohua; Hui, Dafeng; Wu, Xiaoying; Wu, Jianping; Liu, Juxiu; Zhou, Guoyi; Zhang, Deqiang

    2016-02-01

    Soil respiration is a major pathway in the global carbon cycle and its response to environmental changes is an increasing concern. Here we explored how total soil respiration (RT) and its components respond to elevated acid rain in a mixed conifer and broadleaf forest, one of the major forest types in southern China. RT was measured twice a month in the first year under four treatment levels of simulated acid rain (SAR: CK, the local lake water, pH 4.7; T1, water pH 4.0; T2, water pH 3.25; and T3, water pH 2.5), and in the second year, RT, litter-free soil respiration (RS), and litter respiration (RL) were measured simultaneously. The results indicated that the mean rate of RT was 2.84 ± 0.20 μmol CO2 m(-2) s(-1) in the CK plots, and RS and RL contributed 60.7% and 39.3% to RT, respectively. SAR marginally reduced (P = 0.08) RT in the first year, but significantly reduced RT and its two components in the second year (P rain, the decline trend of RT in the forests in southern China appears to be attributable to the decline of soil respiration in the litter layer.

  1. Rebuilding after collapse: evidence for long-term cohort dynamics in the native Hawaiian rain forest

    Science.gov (United States)

    Boehmer, Hans Juergen; Wagner, Helene H.; Jacobi, James D.; Gerrish, Grant C.; Mueller-Dombois, Dieter

    2013-01-01

    Questions: Do long-term observations in permanent plots confirm the conceptual model of Metrosideros polymorpha cohort dynamics as postulated in 1987? Do regeneration patterns occur independently of substrate age, i.e. of direct volcanic disturbance impact? Location: The windward mountain slopes of the younger Mauna Loa and the older Mauna Kea volcanoes (island of Hawaii, USA). Methods: After widespread forest decline (dieback), permanent plots were established in 1976 in 13 dieback and 13 non-dieback patches to monitor the population structure of M. polymorpha at ca. 5-yr intervals. Within each plot of 20 × 20 m, all trees with DBH >2.5 cm were individually tagged, measured and tree vigour assessed; regeneration was quantified in 16 systematically placed subplots of 3 × 5 m. Data collected in the subplots included the total number of M. polymorpha seedlings and saplings (five stem height classes). Here we analyse monitoring data from six time steps from 1976 to 2003 using repeated measures ANOVA to test specific predictions derived from the 1987 conceptual model. Results: Regeneration was significantly different between dieback and non-dieback plots. In dieback plots, the collapse in the 1970s was followed by a ‘sapling wave’ that by 2003 led to new cohort stands of M. polymorpha. In non-dieback stands, seedling emergence did not result in sapling waves over the same period. Instead, a ‘sapling gap’ (i.e. very few or no M. polymorpha saplings) prevailed as typical for mature stands. Canopy dieback in 1976, degree of recovery by 2003 and the number of living trees in 2003 were unrelated to substrate age. Conclusions: Population development of M. polymorpha supports the cohort dynamics model, which predicts rebuilding of the forest with the same canopy species after dieback. The lack of association with substrate age suggests that the long-term maintenance of cohort structure in M. polymorpha does not depend on volcanic disturbance but may be related to

  2. Risk of daytime transmission of malaria in the French Guiana rain forest.

    Science.gov (United States)

    Pommier de Santi, V; Dusfour, I; de Parseval, E; Lespinet, B; Nguyen, C; Gaborit, P; Carinci, R; Hyvert, G; Girod, R; Briolant, S

    2017-02-01

    Between 2008 and 2014, there were 1070 malaria cases reported in French Guiana among members of the armed forces. Most of the malaria outbreaks investigated were multifactorial and followed missions conducted at illegal gold mining sites. For example, a malaria outbreak occurred in September 2013, three weeks after the deployment of 15 soldiers at Dagobert, which is such a site. The attack rate was 53%, with seven Plasmodium vivax infections and one coinfection with both Plasmodium vivax and Plasmodium falciparum. Two months later, an entomological investigation in the field caught 321 anopheles by the human landing catch method. Among them, 282 were Anopheles darlingi. One specimen was PCR-positive for P. vivax, for an infection rate of 0.4% (1/282). In 15.7% of these cases, the An. darlingi was caught during the day. The existence of daytime biting activity by An. darlingi in the Guianese forest might play a key role in malaria outbreaks among military personnel. This finding requires that the Army Health Service adapt its recommendations concerning malaria prevention in French Guiana.

  3. Airborne and spaceborne radar images for geologic and environmental mapping in the Amazon rain forest, Brazil

    Science.gov (United States)

    Ford, John P.; Hurtak, James J.

    1986-01-01

    Spaceborne and airborne radar image of portions of the Middle and Upper Amazon basin in the state of Amazonas and the Territory of Roraima are compared for purposes of geological and environmental mapping. The contrasted illumination geometries and imaging parameters are related to terrain slope and surface roughness characteristics for corresponding areas that were covered by each of the radar imaging systems. Landforms range from deeply dissected mountain and plateau with relief up to 500 m in Roraima, revealing ancient layered rocks through folded residual mountains to deeply beveled pediplain in Amazonas. Geomorphic features provide distinct textural signatures that are characteristic of different rock associations. The principle drainages in the areas covered are the Rio Negro, Rio Branco, and the Rio Japura. Shadowing effects and low radar sensitivity to subtle linear fractures that are aligned parallel or nearly parallel to the direction of radar illumination illustrate the need to obtain multiple coverage with viewing directions about 90 degrees. Perception of standing water and alluvial forest in floodplains varies with incident angle and with season. Multitemporal data sets acquired over periods of years provide an ideal method of monitoring environmental changes.

  4. Converging migration routes of Eurasian hobbies Falco subbuteo crossing the African equatorial rain forest.

    Science.gov (United States)

    Strandberg, Roine; Klaassen, Raymond H G; Hake, Mikael; Olofsson, Patrik; Alerstam, Thomas

    2009-02-22

    Autumn migration of adult Eurasian hobbies Falco subbuteo from Europe to southern Africa was recorded by satellite telemetry and observed routes were compared with randomly simulated routes. Two non-random features of observed routes were revealed: (i) shifts to more westerly longitudes than straight paths to destinations and (ii) strong route convergence towards a restricted area close to the equator (1 degree S, 15 degrees E). The birds migrated south or southwest to approximately 10 degrees N, where they changed to south-easterly courses. The maximal spread between routes at 10 degrees N (2134 km) rapidly decreased to a minimum (67 km) close to the equator. We found a striking relationship between the route convergence and the distribution of continuous rainforest, suggesting that hobbies minimize flight distance across the forest, concentrating in a corridor where habitat may be more suitable for travelling and foraging. With rainforest forming a possible ecological barrier, many migrants may cross the equator either at 15 degrees E, similar to the hobbies, or at 30-40 degrees E, east of the rainforest where large-scale migration is well documented. Much remains to be understood about the role of the rainforest for the evolution and future of the trans-equatorial Palaearctic-African bird migration systems.

  5. Acclimation of seedlings of Gnetum leyboldii Tul. Gnetaceae to light changes in a tropical rain forest

    Directory of Open Access Journals (Sweden)

    Gerardo Celis

    2013-12-01

    Full Text Available The neotropical liana Gnetum leyboldii Gnetaceae is a gymnosperm that resembles angiosperms in wood anatomy, overall morphology, and seed dispersal mechanism. Like other woody lianas, seedlings germinate in the shaded forest understory and start climbing towards the canopy, being eposed to sites with etreme differences in light conditions. However, the etent of physiological and structural adjustment to contrasting light conditions in the early regeneration stages of Gnetum is unknown. To answer this question, we analyzed seedling growth and photosynthetic responses using a common garden eperiment with two light regimes: full sun and low light 20 of full sun at La Selva Biological Station, Costa Rica. We also characterized the germination pattern of this species. We monitored one and half-month old seedlings for four months. Leaf structure finely adapted to light treatments, but gas echange properties were buffered by large seed reserves, which dominated biomass distribution about 50 of the total biomass, followed by stem 27, leaf 16 and root biomass 6 across light conditions. The presence of large seeds and the low photosynthetic rates of seedlings in both environments show that G. leyboldii is specialized to eploit deep shade. More research is needed to determine if the patterns found in G. leyboldii are typical of similar lianas that initially eploit deep-shaded understories in their ascension to the canopy.

  6. Phenology of seed and leaves rain in response to periodic climatic variability in a seasonal wet tropical forest

    Science.gov (United States)

    Matteo, D.; Wright, S. J.; Davies, S. J.; Muller-Landau, H. C.; Wolfe, B.; Detto, M.

    2016-12-01

    Phenology, by controlling the rhythms of plants, plays a fundamental role in regulating access to resources, ecosystem processes, competition among species, interactions with consumers and feedbacks to the climate. In high biodiverse tropical forests, where phenology of flowering and leafing are complex, an adequate representation of phenology must take into account a given set of climatic, edaphic and biotic factors. Climatic factors are particularly important because plants may use them as cues for timing different phenological phases and be influenced by their intensity. Climatic variability can be periodic, if events occur with regular frequency, or aperiodic. One prominent periodic large-scale pattern that causes unusual weather is ENSO event. In general, Central America tends to be dry and warm during a mature phase of an ENSO event, which usually peaks between October and January with a frequency of 2-3 events per decade. Because in many tropical areas the effect of ENSO is highly prominent, it is plausible that plants have adapted their growth and reproduction mechanisms to synchronize ENSO phases, in a similar way that plants do during the seasonal cycle. We used a long dataset (30+ years) of fruits and leaves rains of tropical trees and lianas to determine ecosystem response and species specific response of these phenological events to local climate variability corresponding to the modes of ENSO. Specifically, we tested the hypothesis that phenological responses to ENSO are similar to response to seasonal cycles, i.e., higher litterfall before a warm-dry phase and higher fruiting after such phase, with strong correlation between seeds and leaves. At sub-community level, we evaluated whether evergreen and deciduous, biotic and abiotic dispersers and free and climbing life forms, have the same response to ENSO in terms of leaves and seeds rain. At species level we tested the hypothesis that species with low photosynthetic capacity leaves are more responsive

  7. Distribution of bioluminescent fungi across old-growth and secondary tropical rain forest in Costa Rica

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    Carolina Seas-Carvajal

    2013-06-01

    Full Text Available Most research on bioluminescent fungi is concentrated on their taxonomic relationships, while the basics of their natural history and ecological relationships are poorly understood. In this study, we compared the distribution of bioluminescent fungi between old-growth and secondary forest as related to four different soil types at the tropical rainforest of La Selva Biological Station in Costa Rica. The study was conducted during the wet season of 2009. Bioluminescent fungi were sought following eight different transects distributed evenly in old-growth and secondary forests across four different soil types, covering an area of 9 420m². We found fungi in four different substrates: litter, fallen branches, dead trunks, and roots, for a total of 61 samples. Correspondence analysis showed that the occurrence of fungi and soil types were related (inertia=0.21, p=0.071. We found a significant relationship between the presence of fungi and the distribution of soil types (X²=18.89, df=9, p=0.026. We found only three samples with fruiting bodies, two of which had Mycena and the other had one fungus of the order Xylariales (possibly Hypoxylon sp., Kretzschmariella sp., Xylaria sp.. Future work will concentrate on exploring other aspects of their ecology, such as their dispersal and substrate preference. This information will facilitate field identification and will foster more research on the distribution, seasonality, reproductive phenology and ecological requirements of this group of Fungi.La mayoría de las investigaciones sobre los hongos bioluminiscentes se ha centrado en relaciones taxonómicas. Los aspectos básicos de la historia natural y relaciones ecológicas de este grupo son poco conocidos. En este estudio, comparamos la distribución de hongos bioluminiscentes entre el bosque primario y el secundario en la Estación Biológica La Selva, Costa Rica en relación con cuatro tipos de suelo. El estudio se realizó durante la estación lluviosa

  8. Variation in pH optima of hydrolytic enzyme activities in tropical rain forest soils.

    Science.gov (United States)

    Turner, Benjamin L

    2010-10-01

    Extracellular enzymes synthesized by soil microbes play a central role in the biogeochemical cycling of nutrients in the environment. The pH optima of eight hydrolytic enzymes involved in the cycles of carbon, nitrogen, phosphorus, and sulfur, were assessed in a series of tropical forest soils of contrasting pH values from the Republic of Panama. Assays were conducted using 4-methylumbelliferone-linked fluorogenic substrates in modified universal buffer. Optimum pH values differed markedly among enzymes and soils. Enzymes were grouped into three classes based on their pH optima: (i) enzymes with acidic pH optima that were consistent among soils (cellobiohydrolase, β-xylanase, and arylsulfatase), (ii) enzymes with acidic pH optima that varied systematically with soil pH, with the most acidic pH optima in the most acidic soils (α-glucosidase, β-glucosidase, and N-acetyl-β-glucosaminidase), and (iii) enzymes with an optimum pH in either the acid range or the alkaline range depending on soil pH (phosphomonoesterase and phosphodiesterase). The optimum pH values of phosphomonoesterase were consistent among soils, being 4 to 5 for acid phosphomonoesterase and 10 to 11 for alkaline phosphomonoesterase. In contrast, the optimum pH for phosphodiesterase activity varied systematically with soil pH, with the most acidic pH optima (3.0) in the most acidic soils and the most alkaline pH optima (pH 10) in near-neutral soils. Arylsulfatase activity had a very acidic optimum pH in all soils (pH ≤3.0) irrespective of soil pH. The differences in pH optima may be linked to the origins of the enzymes and/or the degree of stabilization on solid surfaces. The results have important implications for the interpretation of hydrolytic enzyme assays using fluorogenic substrates.

  9. Natural regeneration in a quaternary coastal plain in southern Brazilian Atlantic Rain forest

    Directory of Open Access Journals (Sweden)

    Cleber Ibraim Salimon

    2001-06-01

    Full Text Available Composition, structure and dynamics of an eight year old secondary forest was studied at Reserva Volta Velha (26°04'S; 48°38'W, southern Brazil. A 0.72ha plot was divided into 36 subplots of 20X10m, where all trees/shrubs greater than 1m tall were identified, measured (height/diameter and evaluated (successional status. The results were: (1 95 species collected within 68 genera and 44 families; the most species rich families were Myrtaceae and Asteraceae with 8 species each; (2 the most important species (considering biomass and density were Psidium cattleianum, Eupatorium casarettoi, Ocotea pulchella and Ternstroemia brasiliensis; (3 the most similar area was a fallow abandoned 35 years ago; (4 the higher species diversity were found in border subplots, indicating that most of the species do not tolerate extreme conditions in the center of the opening, and are colonizing the area through the borders.A maior parte das áreas florestais no domínio da Floresta Atlântica se encontra degradada devido a diferentes pressões antrópicas. No intuito de ampliar os conhecimentos sobre relictos de florestas nativas intactas, e também de áreas abandonadas para se obter dados sobre os processos naturais de regeneração, foi realizado um estudo da composição florística, estrutura e dinâmica de uma comunidade vegetal em estágio seral inicial de 8 anos. em Floresta Ombrófila Densa das Terras Baixas, na Reserva Volta Velha, Itapoa-SC, Brasil. Foram utilizados os métodos usuais de coleta, herborização e identificação das espécies encontradas, e a análise estrutural foi feita utilizando-se 36 parcelas retangulares de 20 X 10m, sendo incluídas todas as plantas arbustivo/arbóreas com no mínimo 1 metro de altura. Os resultados obtidos foram os seguintes: 1- Foram encontradas 96 espécies, dentro de 68 gêneros e 44 famílias; as famílias com maior número de espécies foram Myrtaceae e Asteraceae com 8 espécies cada, e o gênero mais

  10. Spatial and multi-temporal analysis of deforestation and quantification of the remnant forests on Porto Rico Island, Paraná, Brazil

    Directory of Open Access Journals (Sweden)

    João Batista Campos

    1999-01-01

    Full Text Available The process of land occupation by the state of Paraná practically decimated its forests. Presently, only 7% from a total area of 83.41% is covered by forests. Most of them are now concentrated in the "Serra do Mar" and in the Iguaçu National Park. With regard to forest cover the most critical region is situated in the northwestern of the state with less than 1% of its area covered by forest. This restricted area mainly consists of conservation units and the islands of the high Paraná River floodplain. The present study consists of a spatial and multi-temporal analysis of deforestation and the quantification of the remnant forests on Porto Rico island (22º45'S; 53º15'W, which have their occupation history linked to the colonization process of the region. Historical aerial photographs of this region were used and the relationship of deforestation with the process of colonization and social transformation of the region is discussed.O processo de ocupação das terras do Paraná praticamente dizimou as florestas do Estado, que originalmente possuía 83,41% de sua área total coberta com florestas. Atualmente remanescem aproximadamente 7% da área com florestas, concentradas na Serra do Mar e no Parque Nacional do Iguaçu. Na região noroeste, a situação é mais crítica, com menos de 1% de sua área coberta por florestas, concentradas, principalmente, em unidades de conservação e nas ilhas da planície de inundação do alto rio Paraná. Esta planície é formada por uma ampla calha aluvial, com inúmeros canais, lagoas e ilhas, que têm sua história de ocupação ligadas ao processo de colonização na região. Neste trabalho, é realizada uma análise espacial e multi-temporal dos desflorestamentos e uma quantificação das florestas remanescentes da ilha Porto Rico (22º45'S; 53º15'W, por meio de fotografias aéreas históricas da região e discutidas as relações destes desflorestamentos com os processo de colonização e transforma

  11. In tropical lowland rain forests monocots have tougher leaves than dicots, and include a new kind of tough leaf.

    Science.gov (United States)

    Dominy, Nathaniel J; Grubb, Peter J; Jackson, Robyn V; Lucas, Peter W; Metcalfe, Daniel J; Svenning, Jens-Christian; Turner, Ian M

    2008-06-01

    There has been little previous work on the toughness of the laminae of monocots in tropical lowland rain forest (TLRF) despite the potential importance of greater toughness in inhibiting herbivory by invertebrates. Of 15 monocot families with >100 species in TLRF, eight have notably high densities of fibres in the lamina so that high values for toughness are expected. In north-eastern Australia punch strength was determined with a penetrometer for both immature leaves (approx. 30 % final area on average) and fully expanded, fully toughened leaves. In Singapore and Panama, fracture toughness was determined with an automated scissors apparatus using fully toughened leaves only. In Australia punch strength was, on average, 7x greater in shade-tolerant monocots than in neighbouring dicots at the immature stage, and 3x greater at the mature stage. In Singapore, shade-tolerant monocots had, on average, 1.3x higher values for fracture toughness than neighbouring dicots. In Panama, both shade-tolerant and gap-demanding monocots were tested; they did not differ in fracture toughness. The monocots had markedly higher values than the dicots whether shade-tolerant or gap-demanding species were considered. It is predicted that monocots will be found to experience lower rates of herbivory by invertebrates than dicots. The tough monocot leaves include both stiff leaves containing relatively little water at saturation (e.g. palms), and leaves which lack stiffness, are rich in water at saturation and roll readily during dry weather or even in bright sun around midday (e.g. gingers, heliconias and marants). Monocot leaves also show that it is possible for leaves to be notably tough throughout the expansion phase of development, something never recorded for dicots. The need to broaden the botanist's mental picture of a 'tough leaf' is emphasized.

  12. Parameterization of Leaf-Level Gas Exchange for Plant Functional Groups From Amazonian Seasonal Tropical Rain Forest

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    Domingues, T. F.; Berry, J. A.; Ometto, J. P.; Martinelli, L. A.; Ehleringer, J. R.

    2004-12-01

    Plant communities exert strong influence over the magnitude of carbon and water cycling through ecosystems by controlling photosynthetic gas exchange and respiratory processes. Leaf-level gas exchange fluxes result from a combination of physiological properties, such as carboxylation capacity, respiration rates and hydraulic conductivity, interacting with environmental drivers such as water and light availability, leaf-to-air vapor pressure deficit, and temperature. Carbon balance models concerned with ecosystem-scale responses have as a common feature the description of eco-physiological properties of vegetation. Here we focus on the parameterization of ecophysiological gas-exchange properties of plant functional groups from a pristine Amazonian seasonally dry tropical rain forest ecosystem (FLONA-Tapajós, Santarém, PA, Brazil). The parameters were specific leaf weight, leaf nitrogen content, leaf carbon isotope ratio, maximum photosynthetic assimilation rate, photosynthetic carboxylation capacity, dark respiration rates, and stomatal conductance to water vapor. Our plant functional groupings were lianas at the top of the canopy, trees at the top of the canopy, mid-canopy trees and undestory trees. Within the functional groups, we found no evidence that leaves acclimated to seasonal changes in precipitation. However, there were life-form dependent distinctions when a combination of parameters was included. Top-canopy lianas were statistically different from top-canopy trees for leaf carbon isotope ratio, maximum photosynthetic assimilation rate, and stomatal conductance to water vapor, suggesting that lianas are more conservative in the use of water, causing a stomatal limitation on photosynthetic assimilation. Top-canopy, mid canopy and understory groupings were distinct for specific leaf weight, leaf nitrogen content, leaf carbon isotope ratio, maximum photosynthetic assimilation rate, and photosynthetic carboxylation capacity. The recognition that plant

  13. Export of nutrients and major ionic solutes from a rain forest catchment in the Central Amazon Basin

    Science.gov (United States)

    Lesack, Lance F. W.

    1993-03-01

    The relative roles of base flow runoff versus storm flow runoff versus subsurface outflow in controlling total export of solutes from a 23.4-ha catchment of undisturbed rain forest in the central Amazon Basin were evaluated from water and solute flux measurements performed over a 1 year period. Solutes exported via 173 storms during the study were estimated from stream water samples collected during base flow conditions and during eight storms, and by utilizing a hydrograph separation technique in combination with a mixing model to partition storm flow from base flow fluxes. Solutes exported by subsurface outflow were estimated from groundwater samples from three nests of piezometers installed into the streambed, and concurrent measurements of hydraulic conductivity and hydraulic head gradients. Base flow discharge represented 92% of water outflow from the basin and was the dominant pathway of solute export. Although storm flow discharge represented only 5% of total water outflow, storm flow solute fluxes represented up to 25% of the total annual export flux, though for many solutes the portion was less. Subsurface outflow represented only 2.5% of total water outflow, and subsurface solute fluxes never represented more than 5% of the total annual export flux. Measurement errors were relatively high for storm flow and subsurface outflow fluxes, but cumulative measurement errors associated with the total solute fluxes exported from the catchment, in most cases, ranged from only ±7% to 14% because base flow fluxes were measured relatively well. The export fluxes of most solutes are substantially less than previously reported for comparable small catchments in the Amazon basin, and these differences cannot be reconciled by the fact that storm flow and subsurface outflows were not appropriately measured in previous studies.

  14. Seasonal patterns of leaf gas exchange and water relations in dry rain forest trees of contrasting leaf phenology.

    Science.gov (United States)

    Choat, Brendan; Ball, Marilyn C; Luly, Jon G; Donnelly, Christine F; Holtum, Joseph A M

    2006-05-01

    Diurnal and seasonal patterns of leaf gas exchange and water relations were examined in tree species of contrasting leaf phenology growing in a seasonally dry tropical rain forest in north-eastern Australia. Two drought-deciduous species, Brachychiton australis (Schott and Endl.) A. Terracc. and Cochlospermum gillivraei Benth., and two evergreen species, Alphitonia excelsa (Fenzal) Benth. and Austromyrtus bidwillii (Benth.) Burret. were studied. The deciduous species had higher specific leaf areas and maximum photosynthetic rates per leaf dry mass in the wet season than the evergreens. During the transition from wet season to dry season, total canopy area was reduced by 70-90% in the deciduous species and stomatal conductance (g(s)) and assimilation rate (A) were markedly lower in the remaining leaves. Deciduous species maintained daytime leaf water potentials (Psi(L)) at close to or above wet season values by a combination of stomatal regulation and reduction in leaf area. Thus, the timing of leaf drop in deciduous species was not associated with large negative values of daytime Psi(L) (greater than -1.6 MPa) or predawn Psi(L) (greater than -1.0 MPa). The deciduous species appeared sensitive to small perturbations in soil and leaf water status that signalled the onset of drought. The evergreen species were less sensitive to the onset of drought and g(s) values were not significantly lower during the transitional period. In the dry season, the evergreen species maintained their canopies despite increasing water-stress; however, unlike Eucalyptus species from northern Australian savannas, A and g(s) were significantly lower than wet season values.

  15. Anti-Streptococcal activity of Brazilian Amazon Rain Forest plant extracts presents potential for preventive strategies against dental caries

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    Juliana Paola Corrêa da SILVA

    2014-04-01

    Full Text Available Caries is a global public health problem, whose control requires the introduction of low-cost treatments, such as strong prevention strategies, minimally invasive techniques and chemical prevention agents. Nature plays an important role as a source of new antibacterial substances that can be used in the prevention of caries, and Brazil is the richest country in terms of biodiversity. Objective: In this study, the disk diffusion method (DDM was used to screen over 2,000 Brazilian Amazon plant extracts against Streptococcus mutans. Material and Methods: Seventeen active plant extracts were identified and fractionated. Extracts and their fractions, obtained by liquid-liquid partition, were tested in the DDM assay and in the microdilution broth assay (MBA to determine their minimal inhibitory concentrations (MICs and minimal bactericidal concentrations (MBCs. The extracts were also subjected to antioxidant analysis by thin layer chromatography. Results: EB271, obtained from Casearia spruceana, showed significant activity against the bacterium in the DDM assay (20.67±0.52 mm, as did EB1129, obtained from Psychotria sp. (Rubiaceae (15.04±2.29 mm. EB1493, obtained from Ipomoea alba, was the only extract to show strong activity against Streptococcus mutans (0.08 mg/mLrain forest, show potential as sources of new antibacterial agents for use as chemical coadjuvants in prevention strategies to treat caries.

  16. Red and Far-Red Solar-Induced Chlorophyll Fluorescence Observations in the Tropical Rain Forest of Costa Rica

    Science.gov (United States)

    Stutz, J.; Grossmann, K.; Seibt, U.; Dierick, D.; Magney, T. S.; Frankenberg, C.

    2017-12-01

    Solar-Induced Chlorophyll Fluorescence (SIF) is a powerful proxy for photosynthetic activity. SIF can be measured using remote sensing from the leaf to the global scale. However, the relationship between SIF, photosynthetic efficiencies, Gross Primary Productivity (GPP), and their response to environmental stress conditions remain poorly constrained. The impact of canopy radiative transfer and viewing geometry at the canopy scale also requires further study. In addition, there is an urgent need for the validation of space-borne SIF measurements, especially above the tropical rain forest where ground observations at the canopy scale are sparse. Here we present observations of SIF in the red and far-red wavelength range, as well various vegetation indices (NDVI, PRI, EVI), made by a novel ground-based spectrometer system, PhotoSpec, at La Selva Biological Station, Costa Rica. Measurements began in March 2017 and have continued ever since. PhotoSpec uses a narrow (0.7 degrees) field-of-view for the simultaneous co-aligned observations of all parameters at a time resolution of 30 seconds. The 2D scanning telescope unit of PhotoSpec was used for regular surveys of around 20 tree species, 2D-raster on canopies of individual trees, as well as elevation survey scans. SIF retrievals were performed using the in-filling of Fraunhofer lines, which allows the accurate observation of SIF under sunny as well as frequent cloudy conditions. The seasonal changes of SIF at La Selva, as well as the red / far-red SIF ratio, for different tree species are presented. 2D-raster scans allow an assessment of the representativeness of narrow field-of-view observations. We will also compare the PhotoSpec data with coincident satellite observations.

  17. Germination and soil seed bank traits of Podocarpus angustifolius (Podocarpaceae: an endemic tree species from Cuban rain forests

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    Pablo Ferrandis

    2011-09-01

    Full Text Available Podocarpus angustifolius is an endangered recalcitrant-seeded small tree, endemic to mountain rain forests in the central and Pinar del Río regions in Cuba. In this study, the germination patterns of P. angustifolius seeds were evaluated and the nature of the soil seed bank was determined. Using a weighted two-factor design, we analyzed the combined germination response to seed source (i.e. freshly matured seeds directly collected from trees versus seeds extracted from soil samples and pretreatment (i.e. seed water-immersion for 48h at room temperature. Germination was delayed for four weeks (≈30 days in all cases, regardless of both factors analyzed. Moreover, nine additional days were necessary to achieve high germination values (in the case of fresh, pretreated seeds. These results overall may indicate the existence of a non-deep simple morphophysiological dormancy in P. angustifolius seeds. The water-immersion significantly enhanced seed germination, probably as a result of the hydration of recalcitrant seeds. Although germination of seeds extracted from soil samples was low, probably due to aging and pathogen effects throughout the time of burial, the study revealed the existence of a persistent soil seed bank (at least short-termed of ≈42 viable seeds per m² in the upper 10cm of soil. Such a record is noteworthy since references to persistent soil seed banks in recalcitrant-seeded species are scarce in the literature. The population consequences derived from the formation of persistent soil seed banks in this endangered species are discussed. Rev. Biol. Trop. 59 (3: 1061-1069. Epub 2011 September 01.

  18. Germination and soil seed bank traits of Podocarpus angustifolius (Podocarpaceae): an endemic tree species from Cuban rain forests.

    Science.gov (United States)

    Ferrandis, Pablo; Bonilla, Marta; Osorio, Licet del Carmen

    2011-09-01

    Podocarpus angustifolius is an endangered recalcitrant-seeded small tree, endemic to mountain rain forests in the central and Pinar del Río regions in Cuba. In this study, the germination patterns of P. angustifolius seeds were evaluated and the nature of the soil seed bank was determined. Using a weighted two-factor design, we analyzed the combined germination response to seed source (i.e. freshly matured seeds directly collected from trees versus seeds extracted from soil samples) and pretreatment (i.e. seed water-immersion for 48h at room temperature). Germination was delayed for four weeks (= 30 days) in all cases, regardless of both factors analyzed. Moreover, nine additional days were necessary to achieve high germination values (in the case of fresh, pretreated seeds). These results overall may indicate the existence of a non-deep simple morphophysiological dormancy in P. angustifolius seeds. The water-immersion significantly enhanced seed germination, probably as a result of the hydration of recalcitrant seeds. Although germination of seeds extracted from soil samples was low, probably due to aging and pathogen effects throughout the time of burial, the study revealed the existence of a persistent soil seed bank (at least short-termed) of approximately 42 viable seeds per m2 in the upper 10cm of soil. Such a record is noteworthy since references to persistent soil seed banks in recalcitrant-seeded species are scarce in the literature. The population consequences derived from the formation of persistent soil seed banks in this endangered species are discussed.

  19. Leaf and soil nitrogen and phosphorus availability in a neotropical rain forest of nutrient-rich soil

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    José Luis Martínez-Sánchez

    2006-06-01

    Full Text Available 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 HCl 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 μg 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. Rev. Biol. Trop. 54(2: 357-361. Epub 2006 Jun 01.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

  20. A Critique on Long-term Impacts of Logging in a Tropical Rain Forest-a Simulation Study

    OpenAIRE

    Rahmawaty

    2006-01-01

    06008760 Logging operations in tropical forests often have severe impacts on the forests. Though only a small portion of trees is harvested, a large portion of the forest may be impacted, oleh Rahmawaty

  1. Spatial distribution by Canistropsis microps (E. Morren ex Mez Leme (Bromeliaceae: Bromelioideae in the Atlantic rain forest in Ilha Grande, Southeastern Brazil

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    AF. Nunes-Freitas

    Full Text Available Canistropsis microps (Bromeliaceae: Bromelioideae is an endemic species of Atlantic rain forest areas in Rio de Janeiro State, which are very abundant in not very disturbed forests in Ilha Grande, on the southern coast of the State. In this study, we analyzed the vertical and horizontal distribution patterns of the species in an area of rain forest with little evidence of disturbance at Vila Dois Rios, Ilha Grande, relating the patterns to sunlight in the microhabitat. We also identified the types of substrate used by the species and the rate of asexual reproduction. Canistropsis microps had high densities (estimated at 84,425 rosettes/ha, and has an aggregated distribution (Id = 2.86. About 80% of the rosettes were generated by clonal growth, whereas less than 20% were produced from seedlings. Most of the rosettes were found on straight tree trunks (DBH > 50 cm. There was a significant inverse correlation between the incidence of sunlight in the habitat and the abundance of individuals. Rosettes were found up to a maximum height of 9.5 m, but most occured between 1.5 and 5.5 m, where light varied from 25 to 50 µmol.s-1.m-2. We conclude that vertical and horizontal distribution patterns in C. microps may be partially explained by the occurrence of appropriate substrate, an intensity of sunlight favorable to the development of the species and to a high rate of vegetative reproduction.

  2. One-year delayed effect of fog on malaria transmission: a time-series analysis in the rain forest area of Mengla County, south-west China

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    Goggins William B

    2008-06-01

    Full Text Available Abstract Background Malaria is a major public health burden in the tropics with the potential to significantly increase in response to climate change. Analyses of data from the recent past can elucidate how short-term variations in weather factors affect malaria transmission. This study explored the impact of climate variability on the transmission of malaria in the tropical rain forest area of Mengla County, south-west China. Methods Ecological time-series analysis was performed on data collected between 1971 and 1999. Auto-regressive integrated moving average (ARIMA models were used to evaluate the relationship between weather factors and malaria incidence. Results At the time scale of months, the predictors for malaria incidence included: minimum temperature, maximum temperature, and fog day frequency. The effect of minimum temperature on malaria incidence was greater in the cool months than in the hot months. The fog day frequency in October had a positive effect on malaria incidence in May of the following year. At the time scale of years, the annual fog day frequency was the only weather predictor of the annual incidence of malaria. Conclusion Fog day frequency was for the first time found to be a predictor of malaria incidence in a rain forest area. The one-year delayed effect of fog on malaria transmission may involve providing water input and maintaining aquatic breeding sites for mosquitoes in vulnerable times when there is little rainfall in the 6-month dry seasons. These findings should be considered in the prediction of future patterns of malaria for similar tropical rain forest areas worldwide.

  3. Tree seed rain and seed removal, but not the seed bank, impede forest recovery in bracken (Pteridium aquilinum (L.) Kuhn)-dominated clearings in the African highlands.

    Science.gov (United States)

    Ssali, Fredrick; Moe, Stein R; Sheil, Douglas

    2018-04-01

    Considerable areas dominated by bracken Pteridium aquilinum (L.) Kuhn occur worldwide and are associated with arrested forest recovery. How forest recovery is impeded in these areas remains poorly understood, especially in the African highlands. The component processes that can lead to recruitment limitation-including low seed arrival, availability and persistence-are important determinants of plant communities and offer a potential explanation for bracken persistence. We investigated key processes that can contribute to recruitment limitation in bracken-dominated clearings in the Bwindi Impenetrable National Park, Uganda. We examined if differences in seed rain (dispersal limitation), soil seed bank, or seed removal (seed viability and persistence) can, individually or in combination, explain the differences in tree regeneration found between bracken-dominated areas and the neighboring forest. These processes were assessed along ten 50-m transects crossing the forest-bracken boundary. When compared to the neighboring forest, bracken clearings had fewer seedlings (bracken 11,557 ± 5482 vs. forest 34,515 ± 6066 seedlings/ha), lower seed rain (949 ± 582 vs. 1605 ± 335 tree seeds m -2  year -1 ), comparable but sparse soil seed bank (304 ± 236 vs. 264 ± 99 viable tree seeds/m 2 ), higher seed removal (70.1% ± 2.4% vs. 40.6% ± 2.4% over a 3-day interval), and markedly higher rodent densities (25.7 ± 5.4 vs. 5.0 ± 1.6 rodents per 100 trapping sessions). Camera traps revealed that rodents were the dominant animals visiting the seeds in our seed removal study. Synthesis : Recruitment limitation contributes to both the slow recovery of forest in bracken-dominated areas, and to the composition of the tree species that occur. Low seed arrival and low persistence of unburied seeds can both explain the reduced density of seedlings found in bracken versus neighboring forest. Seed removal, likely due to rodents, in particular appears sufficient to

  4. Origin and global diversification patterns of tropical rain forests: inferences from a complete genus-level phylogeny of palms

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    Couvreur Thomas LP

    2011-06-01

    Full Text Available Abstract Background Understanding how biodiversity is shaped through time is a fundamental question in biology. Even though tropical rain forests (TRF represent the most diverse terrestrial biomes on the planet, the timing, location and mechanisms of their diversification remain poorly understood. Molecular phylogenies are valuable tools for exploring these issues, but to date most studies have focused only on recent time scales, which minimises their explanatory potential. In order to provide a long-term view of TRF diversification, we constructed the first complete genus-level dated phylogeny of a largely TRF-restricted plant family with a known history dating back to the Cretaceous. Palms (Arecaceae/Palmae are one of the most characteristic and ecologically important components of TRF worldwide, and represent a model group for the investigation of TRF evolution. Results We provide evidence that diversification of extant lineages of palms started during the mid-Cretaceous period about 100 million years ago. Ancestral biome and area reconstructions for the whole family strongly support the hypothesis that palms diversified in a TRF-like environment at northern latitudes. Finally, our results suggest that palms conform to a constant diversification model (the 'museum' model or Yule process, at least until the Neogene, with no evidence for any change in diversification rates even through the Cretaceous/Paleogene mass extinction event. Conclusions Because palms are restricted to TRF and assuming biome conservatism over time, our results suggest the presence of a TRF-like biome in the mid-Cretaceous period of Laurasia, consistent with controversial fossil evidence of the earliest TRF. Throughout its history, the TRF biome is thought to have been highly dynamic and to have fluctuated greatly in extent, but it has persisted even during climatically unfavourable periods. This may have allowed old lineages to survive and contribute to the steady

  5. A new species of Rhinella Fitzinger, 1826 from the Atlantic Rain Forest, Eastern Brazil (Amphibia, Anura, Bufonidae

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    Ulisses Caramaschi

    2006-01-01

    Full Text Available A new species of the genus Rhinella is described from Canavieiras, southern State of Bahia, in the Atlantic Rain Forest of Eastern Brazil. Rhinella hoogmoedi sp. nov. is characterized by the medium size for the genus (SVL 39.4-52.1 mm in males, snout rounded in dorsal view, with a vertical apical ridge which gives a nearly mucronate aspect, and nearly acute in profile, antorbital and supra-orbital crests developed, parietal crest poorly developed, post-orbital crest large, forming a small lateral ledge, tympanum evident, vertebral apophyses not salient on dorsum, presence of a dorsolateral line of pointed tubercles on the external border of the parotoid gland, continuing along the lateral side of body to the groin, a rounded tubercle at the posterior corner of mouth, and vocal slits present. The new species is distributed from the State of Ceará to the State of Paraná, Brazil.Uma nova espécie do gênero Rhinella é descrita de Canavieiras, no sul do Estado da Bahia, na Floresta Atlântica do leste do Brasil. Rhinella hoogmoedi sp. nov. é caracterizada pelo tamanho médio para o gênero (CRA 39,4-52,1 mm em machos, focinho arredondado em vista dorsal, com uma prega apical vertical que lhe dá um aspecto aproximadamente mucronado, e próximo de agudo em perfil, cristas anterorbital e supra-orbital desenvolvidas, crista parietal pouco desenvolvida, crista pós-orbital grande, formando uma pequena aba lateral, tímpano evidente, apófises vertebrais não salientes no dorso, presença de uma linha dorsolateral de tubérculos pontiagudos na borda externa da glândula parotóide, continuando-se ao longo da lateral do corpo até a virilha, um tubérculo arredondado no canto posterior da boca e fendas vocais presentes. A nova espécie está distribuída do Estado do Ceará até o Estado do Paraná, Brasil.

  6. [Soil seed bank formation during early revegetation of areas affected by mining in a tropical rain forest of Chocó, Colombia].

    Science.gov (United States)

    Valois-Cuesta, Hamleth; Martínez-Ruiz, Carolina; Urrutia-Rivas, Yorley

    2017-03-01

    Mining is one of the main economic activities in many tropical regions and is the cause of devastation of large areas of natural tropical forests. The knowledge of the regenerative potential of mining disturbed areas provides valuable information for their ecological restoration. The aim of this study was to evaluate the effect of age of abandonment of mines and their distance from the adjacent forest, on the formation of soil seed bank in abandoned mines in the San Juan, Chocó, Colombia. To do this, we determined the abundance and species composition of the soil seed bank, and the dynamics of seed rain in mines of different cessation period of mining activity (6 and 15 years), and at different distances from the adjacent forest matrix (50 and 100 m). Seed rain was composed by five species of plants with anemocorous dispersion, and was more abundant in the mine of 6 years than in the mine of 15 years. There were no significant differences in the number of seeds collected at 50 m and 100 m from the adjacent forest. The soil seed bank was represented by eight species: two with anemocorous dispersion (common among the seed rain species) and the rest with zoochorous dispersion. The abundance of seeds in the soil did not vary with the age of the mine, but was higher at close distances to the forest edge than far away. During the early revegetation, the formation of the soil seed bank in the mines seems to be related to their proximity to other disturbed areas, rather than their proximity to the adjacent forest or the cessation activity period of mines. Therefore, the establishment of artificial perches or the maintenance of isolated trees in the abandoned mines could favour the arrival of bird-dispersed seeds at mines. However, since the soil seed bank can be significantly affected by the high rainfall in the study area, more studies are needed to evaluate management actions to encourage soil seed bank formation in mines of high-rainfall environments in the Choc

  7. Pollen resources and trophic niche breadth of Apis mellifera and Melipona obscurior (Hymenoptera, Apidae) in a subtropical climate in the Atlantic rain forest of southern Brazil

    OpenAIRE

    Hilgert-Moreira , Suzane; Nascher , Carla; Callegari-Jacques , Sidia; Blochtein , Betina

    2013-01-01

    International audience; Pollen sources that comprise the trophic niche of native bee species Melipona obscurior and introduced Apis mellifera and the breadth of this niche were studied in two areas in the Atlantic rain forest of southern Brazil. Pollen obtained from the forager bees during a period of 12 months showed that the richness of pollen types found in each sample varied from 5 to 21 for A. mellifera and from 1 to 10 for M. obscurior. In both areas, A. mellifera had higher niche bread...

  8. Floristic diversity and vegetation structure of the remnant subtropical broad leaved forests from Kabal valley, Swat, Pakistan

    International Nuclear Information System (INIS)

    Ilyas, M.; Qureshi, R.; Akhtar, N.

    2018-01-01

    Under the prevailing anthropogenic and deteriorating environmental conditions, subtropical broad leaved forests in Pakistan are vanishing at a rapid pace. Muslim communities living in rural areas pay great respect and sanctity to the graveyards and avoid interference with the natural vegetation in these sites. The relics of the natural climax plant communities can be seen in the Muslim graveyards of almost every village of Kabal valley, Swat. Little attention has been given to the significance of cultural norms and religious beliefs in conserving phytodiversity. The present endeavor was undertaken to quantify the existing phytodiversity from the studied area during 2010 to 2014. Species and environmental data from 40 releves measuring 10 x 10 m size laid in different Muslim graveyards was stored in TURBOVEG and exported to JUICE for analysis through Two Way Hierarchical Cluster Analysis and Canonical Correspondence Analysis (CCA). The vegetation comprised of an association dominated by Olea ferruginea and Celtis eriocarpa with five distinct communities based on floristic components and environmental variables. Soil moisture, pH, phosphorus, organic matter content and altitude were the main determining factors in establishing these plant communities. The vegetation was stratified with the highest tree layer (17.48+-2.94m), shrub layer (1.85+-0.28m) and herb layer (65.25+-17.79cm). The canopy covered the area about 84.38+-11.83%, of which tree layer shared 69.25+-16.15%, shrub layer 37.63+-11.43% and herb layer56.50+-11.72%. In all, 229 vascular plant species were recorded from the sampled area. Mean species richness was 28.83+-6.69, followed by Shannon index (2.59+-0.32), Simpson index (0.85+-0.06) and evenness index (0.78+-0.07). The significance of indigenous peoples' beliefs and taboos in biodiversity conservation has been discussed in the paper. (author)

  9. Towards ground-truthing of spaceborne estimates of above-ground life biomass and leaf area index in tropical rain forests

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    P. Köhler

    2010-08-01

    Full Text Available The canopy height h of forests is a key variable which can be obtained using air- or spaceborne remote sensing techniques such as radar interferometry or LIDAR. If new allometric relationships between canopy height and the biomass stored in the vegetation can be established this would offer the possibility for a global monitoring of the above-ground carbon content on land. In the absence of adequate field data we use simulation results of a tropical rain forest growth model to propose what degree of information might be generated from canopy height and thus to enable ground-truthing of potential future satellite observations. We here analyse the correlation between canopy height in a tropical rain forest with other structural characteristics, such as above-ground life biomass (AGB (and thus carbon content of vegetation and leaf area index (LAI and identify how correlation and uncertainty vary for two different spatial scales. The process-based forest growth model FORMIND2.0 was applied to simulate (a undisturbed forest growth and (b a wide range of possible disturbance regimes typically for local tree logging conditions for a tropical rain forest site on Borneo (Sabah, Malaysia in South-East Asia. In both undisturbed and disturbed forests AGB can be expressed as a power-law function of canopy height h (AGB = a · hb with an r2 ~ 60% if data are analysed in a spatial resolution of 20 m × 20 m (0.04 ha, also called plot size. The correlation coefficient of the regression is becoming significant better in the disturbed forest sites (r2 = 91% if data are analysed hectare wide. There seems to exist no functional dependency between LAI and canopy height, but there is also a linear correlation (r2 ~ 60% between AGB and the area fraction of gaps in which the canopy is highly disturbed. A reasonable agreement of our results with observations is obtained from a

  10. Towards ground-truthing of spaceborne estimates of above-ground life biomass and leaf area index in tropical rain forests

    Science.gov (United States)

    Köhler, P.; Huth, A.

    2010-08-01

    The canopy height h of forests is a key variable which can be obtained using air- or spaceborne remote sensing techniques such as radar interferometry or LIDAR. If new allometric relationships between canopy height and the biomass stored in the vegetation can be established this would offer the possibility for a global monitoring of the above-ground carbon content on land. In the absence of adequate field data we use simulation results of a tropical rain forest growth model to propose what degree of information might be generated from canopy height and thus to enable ground-truthing of potential future satellite observations. We here analyse the correlation between canopy height in a tropical rain forest with other structural characteristics, such as above-ground life biomass (AGB) (and thus carbon content of vegetation) and leaf area index (LAI) and identify how correlation and uncertainty vary for two different spatial scales. The process-based forest growth model FORMIND2.0 was applied to simulate (a) undisturbed forest growth and (b) a wide range of possible disturbance regimes typically for local tree logging conditions for a tropical rain forest site on Borneo (Sabah, Malaysia) in South-East Asia. In both undisturbed and disturbed forests AGB can be expressed as a power-law function of canopy height h (AGB = a · hb) with an r2 ~ 60% if data are analysed in a spatial resolution of 20 m × 20 m (0.04 ha, also called plot size). The correlation coefficient of the regression is becoming significant better in the disturbed forest sites (r2 = 91%) if data are analysed hectare wide. There seems to exist no functional dependency between LAI and canopy height, but there is also a linear correlation (r2 ~ 60%) between AGB and the area fraction of gaps in which the canopy is highly disturbed. A reasonable agreement of our results with observations is obtained from a comparison of the simulations with permanent sampling plot (PSP) data from the same region and with the

  11. The Junkyard in the Jungle: Transnational, Transnatural Nature in Karen Tei Yamashita’s Through the Arc of the Rain Forest

    Directory of Open Access Journals (Sweden)

    Begoña Simal

    2010-03-01

    Full Text Available In this new millennium the relatively young field of ecocriticism has had to face important transdisciplinary, transnational, and transnatural challenges. This article attempts to demonstrate how two of the major changes that environmental criticism is currently undergoing, the transnational turn and the transnatural challenge, have both been encoded in Through the Arc of the Rain Forest (1990, the first novel published by Karen Tei Yamashita. I particularly focus on a significant episode in Through the Arc of the Rain Forest, when a peculiar anthropogenic ecosystem is discovered, and interpret it according to Leo Marx’s classic paradigm of “the machine in the garden.” I intend to prove that Yamashita’s novel not only revisits the old master theory but also revamps it by destabilizing the classic human-nature divide inherent in first-wave ecocriticism and by adding the transnational ingredient. Thus, the machine-in-the-garden paradigm is updated in order to incorporate the broadening of current environmental criticism, both literally (globalization and conceptually (transnatural nature. While at times Marx’s paradigm may metamorphose in intriguing ways, the old trope also corroborates its continuing validity. Though filtered by the sieve of globalization and shaken by the emergence of cyborg ecosystems, “the machine in the garden” has survived as a compelling ecocritical framework, even if it occasionally mutates into a junkyard in the jungle.

  12. Cascading Effects of Canopy Opening and Debris Deposition from a Large-Scale Hurricane Experiment in a Tropical Rain Forest

    Science.gov (United States)

    Aaron B. Shiels; Grizelle Gonzalez; D. Jean Lodge; Michael R Willig; Jess K. Zimmerman

    2015-01-01

    Intense hurricanes disturb many tropical forests, but the key mechanisms driving post-hurricane forest changes are not fully understood. In Puerto Rico, we used a replicated factorial experiment to determine the mechanisms of forest change associated with canopy openness and organic matter (debris) addition. Cascading effects from canopy openness accounted for...

  13. Germination and soil seed bank traits of Podocarpus angustifolius (Podocarpaceae: an endemic tree species from Cuban rain forests

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    Pablo Ferrandis

    2011-09-01

    Full Text Available Podocarpus angustifolius is an endangered recalcitrant-seeded small tree, endemic to mountain rain forests in the central and Pinar del Río regions in Cuba. In this study, the germination patterns of P. angustifolius seeds were evaluated and the nature of the soil seed bank was determined. Using a weighted two-factor design, we analyzed the combined germination response to seed source (i.e. freshly matured seeds directly collected from trees versus seeds extracted from soil samples and pretreatment (i.e. seed water-immersion for 48h at room temperature. Germination was delayed for four weeks (≈30 days in all cases, regardless of both factors analyzed. Moreover, nine additional days were necessary to achieve high germination values (in the case of fresh, pretreated seeds. These results overall may indicate the existence of a non-deep simple morphophysiological dormancy in P. angustifolius seeds. The water-immersion significantly enhanced seed germination, probably as a result of the hydration of recalcitrant seeds. Although germination of seeds extracted from soil samples was low, probably due to aging and pathogen effects throughout the time of burial, the study revealed the existence of a persistent soil seed bank (at least short-termed of ≈42 viable seeds per m² in the upper 10cm of soil. Such a record is noteworthy since references to persistent soil seed banks in recalcitrant-seeded species are scarce in the literature. The population consequences derived from the formation of persistent soil seed banks in this endangered species are discussed. Rev. Biol. Trop. 59 (3: 1061-1069. Epub 2011 September 01.Podocarpus angustifolius es un árbol endémico de los bosques lluviosos de la región de Pinar del Río y la parte central de Cuba, que se encuentra en peligro de extinción. En este estudio se evaluó la germinación de sus semillas y la naturaleza del banco de semillas del suelo. Específicamente, se analizó la respuesta germinativa

  14. Effects of rainfall exclusion on leaf gas exchange traits and osmotic adjustment in mature canopy trees of Dryobalanops aromatica (Dipterocarpaceae) in a Malaysian tropical rain forest.

    Science.gov (United States)

    Inoue, Yuta; Ichie, Tomoaki; Kenzo, Tanaka; Yoneyama, Aogu; Kumagai, Tomo'omi; Nakashizuka, Tohru

    2017-10-01

    Climate change exposes vegetation to unusual levels of drought, risking a decline in productivity and an increase in mortality. It still remains unclear how trees and forests respond to such unusual drought, particularly Southeast Asian tropical rain forests. To understand leaf ecophysiological responses of tropical rain forest trees to soil drying, a rainfall exclusion experiment was conducted on mature canopy trees of Dryobalanops aromatica Gaertn.f. (Dipterocarpaceae) for 4 months in an aseasonal tropical rain forest in Sarawak, Malaysia. The rainfall was intercepted by using a soft vinyl chloride sheet. We compared the three control and three treatment trees with respect to leaf water use at the top of the crown, including stomatal conductance (gsmax), photosynthesis (Amax), leaf water potential (predawn: Ψpre; midday: Ψmid), leaf water potential at turgor loss point (πtlp), osmotic potential at full turgor (π100) and a bulk modulus of elasticity (ε). Measurements were taken using tree-tower and canopy-crane systems. During the experiment, the treatment trees suffered drought stress without evidence of canopy dieback in comparison with the control trees; e.g., Ψpre and Ψmid decreased with soil drying. Minimum values of Ψmid in the treatment trees decreased during the experiment, and were lower than πtlp in the control trees. However, the treatment trees also decreased their πtlp by osmotic adjustment, and the values were lower than the minimum values of their Ψmid. In addition, the treatment trees maintained gs and Amax especially in the morning, though at midday, values decreased to half those of the control trees. Decreasing leaf water potential by osmotic adjustment to maintain gs and Amax under soil drying in treatment trees was considered to represent anisohydric behavior. These results suggest that D. aromatica may have high leaf adaptability to drought by regulating leaf water consumption and maintaining turgor pressure to improve its leaf

  15. Soil Type Has a Stronger Role than Dipterocarp Host Species in Shaping the Ectomycorrhizal Fungal Community in a Bornean Lowland Tropical Rain Forest

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    Adam L. Essene

    2017-10-01

    Full Text Available The role that mycorrhizal fungal associations play in the assembly of long-lived tree communities is poorly understood, especially in tropical forests, which have the highest tree diversity of any ecosystem. The lowland tropical rain forests of Southeast Asia are characterized by high levels of species richness within the family Dipterocarpaceae, the entirety of which has been shown to form obligate ectomycorrhizal (ECM fungal associations. Differences in ECM assembly between co-occurring species of dipterocarp have been suggested, but never tested in adult trees, as a mechanism for maintaining the coexistence of closely related tree species in this family. Testing this hypothesis has proven difficult because the assembly of both dipterocarps and their ECM associates co-varies with the same edaphic variables. In this study, we used high-throughput DNA sequencing of soils and Sanger sequencing of root tips to evaluate how ECM fungi were structured within and across a clay–sand soil nutrient ecotone in a mixed-dipterocarp rain forest in Malaysian Borneo. We compared assembly patterns of ECM fungi in bulk soil to ECM root tips collected from three ecologically distinct species of dipterocarp. This design allowed us to test whether ECM fungi are more strongly structured by soil type or host specificity. As with previous studies of ECM fungi on this plot, we observed that clay vs. sand soil type strongly structured both the bulk soil and root tip ECM fungal communities. However, we also observed significantly different ECM communities associated with two of the three dipterocarp species evaluated on this plot. These results suggest that ECM fungal assembly on these species is shaped by a combination of biotic and abiotic factors, and that the soil edaphic niche occupied by different dipterocarp species may be mediated by distinct ECM fungal assemblages.

  16. The remnants of restinga habitats in the brazilian Atlantic Forest of Rio de Janeiro state, Brazil: habitat loss and risk of disappearance

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    CFD. Rocha

    Full Text Available "Restingas" (herbaceous/shrubby coastal sand-dune habitats used to cover most of Rio de Janeiro State coast, and have suffered extensive degradation over the last five centuries. Using satellite images and field work, we identified the remaining restingas in the State, recording the factors that might cause their degradation. We used two mosaics of Landsat 7 scenes (spatial resolution 15 and 30 m to map and evaluate preliminarly the remaining areas and conservation status. Each remnant area was checked in the field, degraded areas within it were mapped and subtracted from the remnants. We identified 21 restinga remnants totalling 105,285 ha. The largest and smallest restinga remnants were Jurubatiba (25,141 ha and Itaipu (23 ha, respectively. We identified 14 causes of degradation. The most important were vegetation removal for housing developments, establishment of exotic plant species, change of original substrate, and selective removal of species of economic importance for the horticultural industry. All restingas had disturbed parts under strong pressure due to human activities. Due to intense habitat loss, and occurrence of endemic/threatened vertebrate species in restinga habitats, we strongly indicate the implementation of new conservation units to protect these fragile remnants. This habitat is steadily decreasing and most remnants lack legal protection. Therefore, under the current human pressure most of this unique habitat is likely to be lost from the State within the next few years.

  17. The remnants of restinga habitats in the brazilian Atlantic Forest of Rio de Janeiro state, Brazil: habitat loss and risk of disappearance.

    Science.gov (United States)

    Rocha, C F D; Bergallo, H G; Van Sluys, M; Alves, M A S; Jamel, C E

    2007-05-01

    "Restingas" (herbaceous/shrubby coastal sand-dune habitats) used to cover most of Rio de Janeiro State coast, and have suffered extensive degradation over the last five centuries. Using satellite images and field work, we identified the remaining restingas in the State, recording the factors that might cause their degradation. We used two mosaics of Landsat 7 scenes (spatial resolution 15 and 30 m) to map and evaluate preliminarly the remaining areas and conservation status. Each remnant area was checked in the field, degraded areas within it were mapped and subtracted from the remnants. We identified 21 restinga remnants totalling 105,285 ha. The largest and smallest restinga remnants were Jurubatiba (25,141 ha) and Itaipu (23 ha), respectively. We identified 14 causes of degradation. The most important were vegetation removal for housing developments, establishment of exotic plant species, change of original substrate, and selective removal of species of economic importance for the horticultural industry. All restingas had disturbed parts under strong pressure due to human activities. Due to intense habitat loss, and occurrence of endemic/threatened vertebrate species in restinga habitats, we strongly indicate the implementation of new conservation units to protect these fragile remnants. This habitat is steadily decreasing and most remnants lack legal protection. Therefore, under the current human pressure most of this unique habitat is likely to be lost from the State within the next few years.

  18. Whither Acid Rain?

    Directory of Open Access Journals (Sweden)

    Peter Brimblecombe

    2000-01-01

    Full Text Available Acid rain, the environmental cause célèbre of the 1980s seems to have vanished from popular conscience. By contrast, scientific research, despite funding difficulties, has continued to produce hundreds of research papers each year. Studies of acid rain taught much about precipitation chemistry, the behaviour of snow packs, long-range transport of pollutants and new issues in the biology of fish and forested ecosystems. There is now evidence of a shift away from research in precipitation and sulfur chemistry, but an impressive theoretical base remains as a legacy.

  19. Forest filled with gaps : effects of gap size on water and nutrient cycling in tropical rain forest : a study in Guyana

    NARCIS (Netherlands)

    Dam, O. van

    2001-01-01

    Guyana's forests are selectively logged and a forest management is desired that is economically sustainable and ecologically responsible. Canopy gaps, created by selective logging, induce changes to microclimatic and edaphic conditions. These changes influence the regeneration of the

  20. Effects of calcium on seed germination, seedling growth and photosynthesis of six forest tree species under simulated acid rain

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Ting-Wu; Wu, Fei-Hua; Wang, Wen-Hua; Chen, Juan; Li, Zhen-Ji; Dong, Xue-Jun; Patton, Janet; Pei, Zhen-Ming; Zheng, Hai-Lei

    2011-04-15

    For several decades, acid rain has been an environmental problem in North America and Europe and is now so in China. The aim of that study was to determine the effects and potential interactions between simulated acid rain (SiAR) and calcium on seed germination of different tree species present in China. Seeds from six tree species were grown is a laboratory where they were spread with SiAR or water as control and where calcium was applied at three levels. Results showed that two species were highly tolerant to SiAR while the others were sensitive; the addition of calcium also had a rescue effect on sensitive seeds but no significant effect on the tolerant ones.

  1. Long-term responses of populations and communities of trees to selective logging in tropical rain forests in Guyana

    NARCIS (Netherlands)

    Arets, E.J.M.M. (Eric Jacobus Monica Maria)

    2005-01-01

    Since only a small area of Guyana's forest can be effectively protected and because timber harvesting is an important source of income, logged forests will play an important role in the conservation of biodiversity in Guyana. Selective logging, in which only a few trees per hectare are harvested and

  2. Analysis of floristic composition and structure as an aid to monitoring protected areas of dense rain forest in southeastern Brazil

    Directory of Open Access Journals (Sweden)

    Eliana Cardoso-Leite

    2013-03-01

    Full Text Available To study forest composition and structure, as well as to facilitate management plans and monitoring programs, we conducted a phytosociological survey in the PE Caverna do Diabo State Park and the Quilombos do Médio Ribeira Environmentally Protected Area, both located within the state of São Paulo, Brazil. We analyzed 20 plots of 400 m² each, including only individuals with a circumference at breast height > 15 cm. We employed cluster analysis and ordination (principal component analysis and correspondence analysis, including species data and abiotic data. We evaluated 1051 individuals, belonging to 155 species in 48 families. Of those 155, 18 were threatened species, 33 were endemic species, and 92 (59.4% were secondary species. The overall Shannon index was 4.524, one of the highest recorded for a dense rainforest in southeastern Brazil. We found that our sample plots fell into three blocks. The first was forest in which there had been human disturbance, showing low species richness, minimal density, and a small relative quantity of biomass. The second was undisturbed mature forest, showing a comparatively larger quantity of biomass. The third was mature forest in which there had been natural intermediate disturbance (dead trees, showing higher species richness and greater density. We identified various groups of species that could be used in monitoring these distinct forest conditions.

  3. Cocoa Intensification Scenarios and Their Predicted Impact on CO2 Emissions, Biodiversity Conservation, and Rural Livelihoods in the Guinea Rain Forest of West Africa

    Science.gov (United States)

    Gockowski, Jim; Sonwa, Denis

    2011-08-01

    The Guinean rain forest (GRF) of West Africa, identified over 20 years ago as a global biodiversity hotspot, had reduced to 113,000 km2 at the start of the new millennium which was 18% of its original area. The principal driver of this environmental change has been the expansion of extensive smallholder agriculture. From 1988 to 2007, the area harvested in the GRF by smallholders of cocoa, cassava, and oil palm increased by 68,000 km2. Field results suggest a high potential for significantly increasing crop yields through increased application of seed-fertilizer technologies. Analyzing land-use change scenarios, it was estimated that had intensified cocoa technology, already developed in the 1960s, been pursued in Cote d'Ivoire, Ghana, Nigeria and Cameroon that over 21,000 km2 of deforestation and forest degradation could have been avoided along with the emission of nearly 1.4 billion t of CO2. Addressing the low productivity of agriculture in the GRF should be one of the principal objectives of REDD climate mitigation programs.

  4. Reproductive phenology, pollination, and fructification of Heliconia spathocircinata Aristeg. (Heliconiaceae in an Atlantic Rain Forest fragment in Rio de Janeiro City

    Directory of Open Access Journals (Sweden)

    Caio César Corrêa Missagia

    2011-09-01

    Full Text Available Aspects of phenology and reproductive biology of Heliconia spathocircinata Aristeg. in border and interior areas of an Atlantic Rain Forest fragment in Rio de Janeiro City, Brazil, are apresented. Four plots of 10x10m were delineated, two on the edge and two inside the forest, and individuals of H. spathocircinata were monitored from June 2009 to June 2010. The observations were carried out from 6 a.m. to 6 p.m. once a week on December and January, and fortnightly the rest of flowering. Heliconia spathocircinata bloomeds between November and March and the fruits were ripe two months after pollination, and there was no significant difference between edge and interior with regard to the period of flowering and fruiting. The fruit-flower ratio averaged 66.6% in the interior and 27% within the forestedge, a considerable difference. The male hummingbirds Thalurania glaucopis Gmelin, and to a lesser extent, female birds of this species, were the most frequent pollinators in the area evaluated, both edge and interior. Other species were identified as pollinators: Phaethornis ruber L., Ramphodon naevius Dumont, Eupetomena macroura Gmelin, and Amazilia fimbriata Gmelin. Of these, only P. ruber was found in both environments.

  5. Species-specific growth responses to climate variations in understory trees of a Central African rain forest

    NARCIS (Netherlands)

    Couralet, C.; Sterck, F.J.; Sass-Klaassen, U.; Acker, Van J.; Beekman, H.

    2010-01-01

    Basic knowledge of the relationships between tree growth and environmental variables is crucial for understanding forest dynamics and predicting vegetation responses to climate variations. Trees growing in tropical areas with a clear seasonality in rainfall often form annual growth rings. In the

  6. Potential of airborne radar to support the assessment of land cover in a tropical rain forest environment

    NARCIS (Netherlands)

    Sanden, van der J.J.; Hoekman, D.H.

    1999-01-01

    The potential of airborne radar systems as tools for collecting information in support of the assessment of tropical primary forests and derived cover types was examined. SAR systems operating with high spatial resolutions and different wavelengths (i.e., X-, C-, L- and P-band) acquired data in

  7. Soil changes induced by rubber and tea plantation establishment: comparison with tropical rain forest soil in Xishuangbanna, SW China.

    Science.gov (United States)

    Li, Hongmei; Ma, Youxin; Liu, Wenjie; Liu, Wenjun

    2012-11-01

    Over the past thirty years, Xishuangbanna in Southwestern China has seen dramatic changes in land use where large areas of tropical forest and fallow land have been converted to rubber and tea plantations. In this study we evaluated the effects of land use and slope on soil properties in seven common disturbed and undisturbed land-types. Results indicated that all soils were acidic, with pH values significantly higher in the 3- and 28-year-old rubber plantations. The tropical forests had the lowest bulk densities, especially significantly lower from the top 10 cm of soil, and highest soil organic matter concentrations. Soil moisture content at topsoil was highest in the mature rubber plantation. Soils in the tropical forests and abandoned cultivated land had inorganic N (IN) concentrations approximately equal in NH(4) (+)-N and NO(3) (-)-N. However, soil IN pools were dominated by NH(4) (+)-N in the rubber and tea plantations. This trend suggests that conversion of tropical forest to rubber and tea plantations increases NH(4) (+)-N concentration and decreases NO(3) (-)-N concentration, with the most pronounced effect in plantations that are more frequently fertilized. Soil moisture content, IN, NH(4) (+)-N and NO(3) (-)-N concentrations within all sites were higher in the rainy season than in the dry season. Significant differences in the soil moisture content, and IN, NH(4) (+)-N and NO(3) (-)-N concentration was detected for both land uses and sampling season effects, as well as interactions. Higher concentrations of NH(4) (+)-N were measured at the upper slopes of all sites, but NO(3) (-)-N concentrations were highest at the lower slope in the rubber plantations and lowest at the lower slopes at all other. Thus, the conversion of tropical forests to rubber and tea plantations can have a profound effect on soil NH(4) (+)-N and NO(3) (-)-N concentrations. Options for improved soil management in plantations are discussed.

  8. An ant-plant by-product mutualism is robust to selective logging of rain forest and conversion to oil palm plantation.

    Science.gov (United States)

    Fayle, Tom M; Edwards, David P; Foster, William A; Yusah, Kalsum M; Turner, Edgar C

    2015-06-01

    Anthropogenic disturbance and the spread of non-native species disrupt natural communities, but also create novel interactions between species. By-product mutualisms, in which benefits accrue as side effects of partner behaviour or morphology, are often non-specific and hence may persist in novel ecosystems. We tested this hypothesis for a two-way by-product mutualism between epiphytic ferns and their ant inhabitants in the Bornean rain forest, in which ants gain housing in root-masses while ferns gain protection from herbivores. Specifically, we assessed how the specificity (overlap between fern and ground-dwelling ants) and the benefits of this interaction are altered by selective logging and conversion to an oil palm plantation habitat. We found that despite the high turnover of ant species, ant protection against herbivores persisted in modified habitats. However, in ferns growing in the oil palm plantation, ant occupancy, abundance and species richness declined, potentially due to the harsher microclimate. The specificity of the fern-ant interactions was also lower in the oil palm plantation habitat than in the forest habitats. We found no correlations between colony size and fern size in modified habitats, and hence no evidence for partner fidelity feedbacks, in which ants are incentivised to protect fern hosts. Per species, non-native ant species in the oil palm plantation habitat (18 % of occurrences) were as important as native ones in terms of fern protection and contributed to an increase in ant abundance and species richness with fern size. We conclude that this by-product mutualism persists in logged forest and oil palm plantation habitats, with no detectable shift in partner benefits. Such persistence of generalist interactions in novel ecosystems may be important for driving ecosystem functioning.

  9. Wet canopy evaporation from a Puerto Rican lower montane rain forest: the importance of realistically estimated aerodynamic conductance

    Science.gov (United States)

    F. Holwerda; L.A. Bruijnzeel; F.N. Scatena; H.F. Vugts; A.G.C.A. Meesters

    2012-01-01

    Rainfall interception (I) was measured in 20 m tall Puerto Rican tropical forest with complex topography for a 1-year period using totalizing throughfall (TF) and stemflow (SF) gauges that were measured every 2–3 days. Measured values were then compared to evaporation under saturated canopy conditions (E) determined with the Penman–Monteith (P–M) equation, using (i)...

  10. Life-history and ecological distribution of chameleons (Reptilia, Chamaeleonidae) from the rain forests of Nigeria: conservation implications

    OpenAIRE

    Akani, G. C.; Ogbalu, O. K.; Luiselli, L.

    2001-01-01

    Five species of chameleons were observed in the continuous forest zone of southern Nigeria: Chamaeleo gracilis gracilis Hallowell, 1842, Chamaeleo owenii Gray, 1831, Chamaeleo cristatus Stutchbury, 1837, Chamaeleo wiedersheimi Nieden, 1910, and Rhampholeon spectrum (Bucholz 1874). Many original locality records are presented for each species. One species is apparently rare and confined to montane habitats (C. wiedersheimi), another species is relatively common and its habitat is generalist (C...

  11. Discovery of the Dinoponera lucida male (Hymenoptera, Formicidae), a threatened giant ant from the Atlantic rain forest.

    Science.gov (United States)

    Escárraga, Mayron E; Lattke, John E; Azevedo, Celso O

    2017-11-10

    The male of the endangered ant Dinoponera lucida Emery is described, providing morphometric measurements, high-resolution images, and a distribution map of the species. This ant inhabits the Brazilian Atlantic forest, an ecosystem strongly impacted by fragmentation. The males show clear morphological differences from the known males of other species of Dinoponera. We briefly discuss the relevance of the male description for the conservation strategies of this ant.

  12. Do Epigeal Termite Mounds Increase the Diversity of Plant Habitats in a Tropical Rain Forest in Peninsular Malaysia?

    Science.gov (United States)

    Beaudrot, Lydia; Du, Yanjun; Rahman Kassim, Abdul; Rejmánek, Marcel; Harrison, Rhett D.

    2011-01-01

    The extent to which environmental heterogeneity can account for tree species coexistence in diverse ecosystems, such as tropical rainforests, is hotly debated, although the importance of spatial variability in contributing to species co-existence is well recognized. Termites contribute to the micro-topographical and nutrient spatial heterogeneity of tropical forests. We therefore investigated whether epigeal termite mounds could contribute to the coexistence of plant species within a 50 ha plot at Pasoh Forest Reserve, Malaysia. Overall, stem density was significantly higher on mounds than in their immediate surroundings, but tree species diversity was significantly lower. Canonical correspondence analysis showed that location on or off mounds significantly influenced species distribution when stems were characterized by basal area. Like studies of termite mounds in other ecosystems, our results suggest that epigeal termite mounds provide a specific microhabitat for the enhanced growth and survival of certain species in these species-rich tropical forests. However, the extent to which epigeal termite mounds facilitate species coexistence warrants further investigation. PMID:21625558

  13. Remnant lipoproteins and atherosclerosis

    NARCIS (Netherlands)

    Twickler, Th. B.; Dallinga-Thie, G. M.; Chapman, M. J.; Cohn, J. S.

    2005-01-01

    A recently developed assay for quantification of remnant-like particle cholesterol has provided considerable evidence that reinforces the concept that elevated levels of plasma remnants are associated with increased cardiovascular disease in different populations and distinct patient groups. In this

  14. Influence of Incomplete Mixing on the OH-Isoprene Reaction in the Lower Troposphere - Measurements Above the Amazon Rain Forest and General Considerations

    Science.gov (United States)

    Sörgel, M.; Dlugi, R. J. W.; Berger, M.; Mallik, C.; Tsokankunku, A.; Zelger, M.; Acevedo, O. C.; Dias, N. L.; Hofzumahaus, A.; Kesselmeier, J.; Kramm, G.; Marno, D. R.; Martinez, M.; Nölscher, A.; H G, O.; Pfannerstill, E.; Bourtsoukidis, E.; Rohrer, F.; Tauer, S.; Williams, J.; Yanez Serrano, A. M.; Andreae, M. O.; Harder, H.

    2017-12-01

    Incomplete mixing of reactants in the atmosphere (segregation) causes reduced reaction rates compared to laboratory values derived for well mixed conditions. To adequately determine the actual reaction rates in a variety of natural environments where the distribution of sources and sinks leads to inhomogeneous distribution of reactants, the intensity of segregation (IS) has to be taken into account. Although, there has been considerable progress in modeling IS in the boundary layer within the last 30 years, calculations from direct observations are still sparse as high time resolution and time synchronization are required. OH-radicals are the most important oxidizing agent in the atmosphere, and are therefore regarded as the detergent of the atmosphere, reacting with the majority of atmospheric pollutants and therefore accelerating their removal from the atmosphere. Hence, to understand atmospheric self-cleansing, we need to quantify and understand the budgets (sources and sinks) of OH. As it is a fast reacting compound, for some of its reactants mixing will limit the reaction rate. The reaction of isoprene and OH radicals has gained considerable interest in recent years since large discrepancies between modeled and measured OH have been found mainly in high isoprene environments. This motivated not only laboratory studies on unknown recycling mechanisms for OH in this reaction, but also modeling work and field studies on the effect of segregation on this reaction. We measured OH radicals, isoprene and other species that are either precursors of OH or promote OH recycling (e.g. O3, NOx, HO2, H2O) with high time resolution (1-10 Hz) closely above a rain forest canopy (at 41 m above ground level) at the ATTO (Amazon Tall Tower Observatory) site (02°08'38.8''S, 58°59'59.5''W). The site is characterized by high isoprene (up to 20 ppb) and low NO (50 -500 ppt). Simultaneous measurements of OH and isoprene with high time resolution so far have been sparse. To our

  15. Life-history and ecological distribution of chameleons (Reptilia, Chamaeleonidae from the rain forests of Nigeria: conservation implications

    Directory of Open Access Journals (Sweden)

    Akani, G. C.

    2001-12-01

    Full Text Available Five species of chameleons were observed in the continuous forest zone of southern Nigeria: Chamaeleo gracilis gracilis Hallowell, 1842, Chamaeleo owenii Gray, 1831, Chamaeleo cristatus Stutchbury, 1837, Chamaeleo wiedersheimi Nieden, 1910, and Rhampholeon spectrum (Bucholz 1874. Many original locality records are presented for each species. One species is apparently rare and confined to montane habitats (C. wiedersheimi, another species is relatively common and its habitat is generalist (C. gracilis, and the other three species are vulnerable and limited to specific micro-habitats. Female R. spectrum had clutch sizes of two eggs each and exhibited a prolonged reproductive season with oviposition likely occurring during the late phase of the dry season. Females of both C. cristatus (clutch sizes: 11-14 eggs and C. owenii (clutch sizes: 15-19 eggs have a shorter reproductive season with oviposition occurring most probably at the interphase between the end of the wet season and the onset of the dry season, and female C. gracilis (clutch sizes: 14-23 eggs appeared to exhibit two distinct oviposition periods (one at the interphase between the end of the wet season and the onset of the dry season, and one at the peak phase of the dry season. Diets of four sympatric species of chameleons consisted almost exclusively of arthropods. There were significant inter-group differences at either intra-specific level (with the females of the two best studied species, i.e. R. spectrum and C. gracilis, having a wider food niche breadth than males or inter-specific level (with a continuum of dietary specialization from the less generalist (C. cristatus to the more generalist (C. gracilis. However, ‘thread-trailing’ experiments indicated that activity patterns of Nigerian chameleons were relatively similar among species. The overall abundance of chameleons (as estimated from the number of specimens observed in the time unit of field effort was relatively

  16. Sea Surface Temperatures Mediated by the El Niño-Southern Oscillation Affect Birds Breeding in Temperate Coastal Rain Forests

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    Anthony J. Gaston

    2005-12-01

    Full Text Available We studied the timing of breeding and juvenile/adult ratios among songbirds in temperate rain forests over four years on the Haida Gwaii (Queen Charlotte Islands archipelago, British Columbia. In May 1998, air temperatures in Haida Gwaii were above average, whereas in 1999 they were the lowest in 20 yr: temperatures in the other two years were closer to normal, although 2001 was almost as cold as 1999. Temperatures closely followed the patterns of sea surface temperatures created by the 1997-1998 El Niño, i.e., warm, event and the subsequent strong La Niña, i.e., cool, event. Timing of breeding, as measured by the first capture of juveniles or by direct observations of hatching, varied by approximately 19 d between the earliest (1998 and latest (1999 years. In 1998, the proportion of juveniles among birds trapped increased steeply as soon as young birds began to appear. In other years, the rate of increase was slower. In 1999, the peak proportions of hatching-year individuals among the foliage-gleaning insectivores, i.e., the Orange-crowned Warbler (Vermivora celata, Townsend's Warbler (Dendroica townsendi, and the Golden-crowned Kinglet (Regulus satrapa, were lower than in other years, with almost no young Orange-crowned Warblers captured at all. The pattern of variation in the timing of breeding and in the proportion of hatching-year individuals trapped fitted the temperature data well, although rainfall may also have contributed. We concluded that changes mediated by El Niño-Southern Oscillation (ENSO in sea surface temperatures off northern British Columbia, through their effects on air temperatures, had a strong effect on the breeding of forest birds, to the point of causing nearly complete reproductive failure for one species in 1999. An intensification of the ENSO cycle could lead to more erratic reproduction for some species.

  17. Changes in soil carbon and nutrients following 6 years of litter removal and addition in a tropical semi-evergreen rain forest

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    E. V. J. Tanner

    2016-11-01

    Full Text Available Increasing atmospheric CO2 and temperature may increase forest productivity, including litterfall, but the consequences for soil organic matter remain poorly understood. To address this, we measured soil carbon and nutrient concentrations at nine depths to 2 m after 6 years of continuous litter removal and litter addition in a semi-evergreen rain forest in Panama. Soils in litter addition plots, compared to litter removal plots, had higher pH and contained greater concentrations of KCl-extractable nitrate (both to 30 cm; Mehlich-III extractable phosphorus and total carbon (both to 20 cm; total nitrogen (to 15 cm; Mehlich-III calcium (to 10 cm; and Mehlich-III magnesium and lower bulk density (both to 5 cm. In contrast, litter manipulation did not affect ammonium, manganese, potassium or zinc, and soils deeper than 30 cm did not differ for any nutrient. Comparison with previous analyses in the experiment indicates that the effect of litter manipulation on nutrient concentrations and the depth to which the effects are significant are increasing with time. To allow for changes in bulk density in calculation of changes in carbon stocks, we standardized total carbon and nitrogen on the basis of a constant mineral mass. For 200 kg m−2 of mineral soil (approximately the upper 20 cm of the profile about 0.5 kg C m−2 was “missing” from the litter removal plots, with a similar amount accumulated in the litter addition plots. There was an additional 0.4 kg C m−2 extra in the litter standing crop of the litter addition plots compared to the control. This increase in carbon in surface soil and the litter standing crop can be interpreted as a potential partial mitigation of the effects of increasing CO2 concentrations in the atmosphere.

  18. Dero (Allodero lutzi Michaelsen, 1926 (Oligochaeta: Naididae associated with Scinax fuscovarius (Lutz, 1925 (Anura: Hylidae from Semi-deciduous Atlantic Rain Forest, southern Brazil

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    FH. Oda

    Full Text Available Amphibians are hosts for a wide variety of ecto- and endoparasites, such as protozoans and parasitic worms. Naididae is a family of Oligochaeta whose species live on a wide range of substrates, including mollusks, aquatic macrophytes, sponges, mosses, liverworts, and filamentous algae. However, some species are known as endoparasitic from vertebrates, such as Dero (Allodero lutzi, which is parasitic of the urinary tracts of frogs, but also have a free-living stage. Specimens in the parasitic stage lack dorsal setae, branchial fossa, and gills. Here we report the occurrence of D. (A. lutzi associated with anuran Scinax fuscovarius from Semi-deciduous Atlantic Rain Forest in southern Brazil. The study took place at the Caiuá Ecological Station, Diamante do Norte, Paraná, southern Brazil. Seven specimens of S. fuscovarius were examined for parasites but only one was infected. Parasites occurred in ureters and urinary bladder. Previous records of this D. (A. lutzi include the Brazilian States of Santa Catarina, São Paulo, Rio de Janeiro, and Minas Gerais, as well as Cuba and North America. This is a new locality record for this species in Brazil. Reports of Dero (Allodero lutzi are rare, due to difficulty of observation, and such events are restricted only the fortuitous cases. It is important to emphasize the necessity of future studies, which are fundamental to the understanding of biological and ecological aspects of this species.

  19. Helminth parasite communities of two Physalaemus cuvieri Fitzinger, 1826 (Anura: Leiuperidae populations under different conditions of habitat integrity in the Atlantic Rain Forest of Brazil

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    A. Aguiar

    Full Text Available Abstract Adults of Physalaemus cuvieri were collected and necropsied between November 2009 and January 2010. This was carried out in order to report and compare the helminth fauna associated with two populations of this anuran species from the Brazilian Atlantic rain forest under different conditions of habitat integrity. The hosts from the disturbed area were parasitized with five helminth taxa: Cosmocerca parva, Aplectana sp., Physaloptera sp., Rhabdias sp., Oswaldocruzia subauricularis (Nematoda and Polystoma cuvieri (Monogenea while those from the preserved area had four helminth taxa: C. parva, Aplectana sp., Physaloptera sp., Rhabdias sp., and Acanthocephalus saopaulensis (Acanthocephala. Prevalence, mean intensity of infection, mean abundance, mean richness, importance index and dominance frequency of helminth component communities were similar in both areas. The helminth community associated with anurans from the disturbed area had higher diversity than that from the preserved area. This study is the first to report on the acanthocephalan parasites of Ph. cuvieri, and the similarity between helminth fauna composition of two host populations under different selective pressures.

  20. Combination of support vector machine, artificial neural network and random forest for improving the classification of convective and stratiform rain using spectral features of SEVIRI data

    Science.gov (United States)

    Lazri, Mourad; Ameur, Soltane

    2018-05-01

    A model combining three classifiers, namely Support vector machine, Artificial neural network and Random forest (SAR) is designed for improving the classification of convective and stratiform rain. This model (SAR model) has been trained and then tested on a datasets derived from MSG-SEVIRI (Meteosat Second Generation-Spinning Enhanced Visible and Infrared Imager). Well-classified, mid-classified and misclassified pixels are determined from the combination of three classifiers. Mid-classified and misclassified pixels that are considered unreliable pixels are reclassified by using a novel training of the developed scheme. In this novel training, only the input data corresponding to the pixels in question to are used. This whole process is repeated a second time and applied to mid-classified and misclassified pixels separately. Learning and validation of the developed scheme are realized against co-located data observed by ground radar. The developed scheme outperformed different classifiers used separately and reached 97.40% of overall accuracy of classification.

  1. Allometric relationships predicting foliar biomass and leaf area:sapwood area ratio from tree height in five Costa Rican rain forest species.

    Science.gov (United States)

    Calvo-Alvarado, J C; McDowell, N G; Waring, R H

    2008-11-01

    We developed allometric equations to predict whole-tree leaf area (A(l)), leaf biomass (M(l)) and leaf area to sapwood area ratio (A(l):A(s)) in five rain forest tree species of Costa Rica: Pentaclethra macroloba (Willd.) Kuntze (Fabaceae/Mim), Carapa guianensis Aubl. (Meliaceae), Vochysia ferru-gi-nea Mart. (Vochysiaceae), Virola koshnii Warb. (Myristicaceae) and Tetragastris panamensis (Engl.) Kuntze (Burseraceae). By destructive analyses (n = 11-14 trees per species), we observed strong nonlinear allometric relationships (r(2) > or = 0.9) for predicting A(l) or M(l) from stem diameters or A(s) measured at breast height. Linear relationships were less accurate. In general, A(l):A(s) at breast height increased linearly with tree height except for Penta-clethra, which showed a negative trend. All species, however, showed increased total A(l) with height. The observation that four of the five species increased in A(l):A(s) with height is consistent with hypotheses about trade--offs between morphological and anatomical adaptations that favor efficient water flow through variation in the amount of leaf area supported by sapwood and those imposed by the need to respond quickly to light gaps in the canopy.

  2. International joint research of reforestation techniques for tropical rain forests in Indonesia; Indonesia tono nettairin saisei gijutsu no kyodo kenkyu ni tsuite

    Energy Technology Data Exchange (ETDEWEB)

    Watanabe, T. [Kansai Electric Power Co. Inc., Osaka (Japan)

    1998-10-30

    The purposes of this research are to establish large-scale reforestation techniques, and to transfer these techniques into Indonesia for contributing to the preservation of tropical rain forests and the protection of global warming. Lauan trees provide disease and drying resistance properties by inoculating their roots with mycorrhizal fungi, to promote their growth. This is due to the symbiotic relationship between them, in which mycelia of mycorrhizal fungi collect and bring water and nutritive substances in the soil to the roots of lauan trees and intake sugars from the roots as nutrition. Since lauan trees are local variety, they are suitable for the preservation of biosystem. Since their growth life is long, they are suitable for the fixation of CO2. However, the reforestation techniques have not yet been established. Between FY 1992 and 1997, a high survival rate about 60% was obtained through a method in which natural seedlings in mountains were implanted and a method in which seeds were planted in the nursery. About 34000 lauan trees have been planted for the reforestation tests. An inoculation method was established for the accelerated growth of seedlings with mycorrhizal fungi. Through the inoculation, the growth rate was increased up to three times of that without inoculation. The lauan trees grew up to 5 m, and the survival rate was also increased up to twice. 11 figs., 3 tabs.

  3. The orchid-bee faunas (Hymenoptera: Apidae of ‘Reserva Ecológica Michelin’, ‘RPPN Serra Bonita’ and one Atlantic Forest remnant in the state of Bahia, Brazil, with new geographic records

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    A Nemésio

    Full Text Available The orchid bee faunas of two private natural preserves, ‘Reserva Particular do Patrimônio Natural da Serra Bonita’ (RSB and ‘Reserva Ecológica Michelin’ (REM, and a forest fragment inside the campus of the ‘Universidade Estadual de Santa Cruz’, were surveyed for the first time. All three areas constitute Atlantic Forest remnants in the southern portion of the state of Bahia, Brazil. A total of 1,782 males belonging to 32 species were actively collected with insect nets during 90 hours of field work from November, 2009, to January, 2012. Euglossa cyanochlora Moure, 1996—one of the rarest orchid bee species—was found at RSB and REM, the latter representing the northernmost record for this species. Euglossa cognata, Moure, 1970 was found at RSB, the northernmost record for this species in the Atlantic Forest and the only recent record for this species at the northern border of Jequitinhonha river.

  4. Influence of land crabs Gecarcinus quadratus (Gecarcinidae on distributions of organic carbon and roots in a Costa Rican rain forest

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    Peter M Sherman

    2006-03-01

    Full Text Available In Costa Rica’s Corcovado National Park,the fossorial land crab, Gecarcinus quadratus (Gecarcinidae, densely populates (1-6 m-2 a region of forest extending from the Park’s Pacific coastline inland to ca.600 m. Throughout this coastal forest (‘crabzone’, crabs selectively forage for fallen leaves and relocate them to subterranean burrow chambers. Comparisons between surface soils (0 -15 cm sampled from the crabzone and forest lying immediately inland that is naturally devoid of crabs (‘crabless zone’ suggest that crabzone top soils contained less organic carbon and fewer fine and very fine roots. In contrast, soils sampled from 70 -100 cm depths in the crabzone contained twice the carbon of the crabless zone during the dry season but similar values during the wet season. Two years of experimental crab exclusion from 25 m² replicates established in the crabzone resulted in 16% more organic carbon content in surface soils relative to baseline conditions (n.s. and 22% more carbon than final control values (P El cangrejo Gecarcinus quadratus (Gecarcinidae habita madrigueras terrestres y afecta el retorno de carbón orgánico a los suelos de los bosques lluviosos al reducir la acumulación de hojarasca y alterar su proceso de descomposición. En el Parque Nacional Corcovado en Costa Rica, G. quadratus vive en altas densidades (de 1-6 cangrejos m-2 en una franja boscosa que se extiende desde la costa del Océano Pacífico hasta 600 m tierra adentro. En esta región de bosque costero (‘zona cangrejera’, los cangrejos buscan alimento selectivamente en la hojarasca, trasladando lo que recolectan a sus cuevas de más de 1 m de profundidad. Comparaciones entre la superficie de los suelos de la zona cangrejera y los de la región inmediata pero más lejana a la costa y sin cangrejos (‘zona no-cangrejera’, revelan que la capa superficial del suelo (a 10 cm en la zona cangrejera contiene 39% menos carbono orgánico, 72% menos ra

  5. Cervical Chondrocutaneous Branchial Remnants.

    Science.gov (United States)

    Klockars, Tuomas; Kajosaari, Lauri

    2017-03-01

      Cervical chondrocutaneous branchial remnants are rare malformations usually found in the lower neck. As high as 76% of patients have been reported to have associated anomalies. We review the literature and report a case series of seven patients with cervical cartilaginous remnants.   A retrospective case series of seven patients identified from the electronic hospital records.   Seven patients with cervical chondrocutaneous branchial remnants were identified (six boys and one girl). Only one of the patients had associated anomalies.   A review of the literature revealed no evidence for sinuses or cysts related to cervical chondrocutaneous branchial remnants. Operative treatment can be postponed to a suitable and safe age. There is marked variation in the reported prevalence of associated anomalies, ranging from 11% to 76%.

  6. Effects of simulated acid rain on soil and soil solution chemistry in a monsoon evergreen broad-leaved forest in southern China.

    Science.gov (United States)

    Qiu, Qingyan; Wu, Jianping; Liang, Guohua; Liu, Juxiu; Chu, Guowei; Zhou, Guoyi; Zhang, Deqiang

    2015-05-01

    Acid rain is an environmental problem of increasing concern in China. In this study, a laboratory leaching column experiment with acid forest soil was set up to investigate the responses of soil and soil solution chemistry to simulated acid rain (SAR). Five pH levels of SAR were set: 2.5, 3.0, 3.5, 4.0, and 4.5 (as a control, CK). The results showed that soil acidification would occur when the pH of SAR was ≤3.5. The concentrations of NO₃(-)and Ca(2+) in the soil increased significantly when the pH of SAR fell 3.5. The concentration of SO₄(2-) in the soil increased significantly when the pH of SAR was soil solution chemistry became increasingly apparent as the experiment proceeded (except for Na(+) and dissolved organic carbon (DOC)). The net exports of NO₃(-), SO₄(2-), Mg(2+), and Ca(2+) increased about 42-86% under pH 2.5 treatment as compared to CK. The Ca(2+) was sensitive to SAR, and the soil could release Ca(2+) through mineral weathering to mitigate soil acidification. The concentration of exchangeable Al(3+) in the soil increased with increasing the acidity of SAR. The releases of soluble Al and Fe were SAR pH dependent, and their net exports under pH 2.5 treatment were 19.6 and 5.5 times, respectively, higher than that under CK. The net export of DOC was reduced by 12-29% under SAR treatments as compared to CK. Our results indicate the chemical constituents in the soil are more sensitive to SAR than those in the soil solution, and the effects of SAR on soil solution chemistry depend not only on the intensity of SAR but also on the duration of SAR addition. The soil and soil solution chemistry in this region may not be affected by current precipitation (pH≈4.5) in short term, but the soil and soil leachate chemistry may change dramatically if the pH of precipitation were below 3.5 and 3.0, respectively.

  7. Cave Conservation Priority Index to Adopt a Rapid Protection Strategy: A Case Study in Brazilian Atlantic Rain Forest

    Science.gov (United States)

    Souza Silva, Marconi; Martins, Rogério Parentoni; Ferreira, Rodrigo Lopes

    2015-02-01

    Cave environments are characterized by possessing specialized fauna living in high environmental stability with limited food conditions. These fauna are highly vulnerable to impacts, because this condition can frequently be easily altered. Moreover, environmental determinants of the biodiversity patterns of caves remain poorly understood and protected. Therefore, the main goal of this work is to propose a cave conservation priority index (CCPi) for a rapid assessment for troglobiotic and troglophile protection. Furthermore, the troglobiotic diversity, distribution and threats have been mapped in the Brazilian Atlantic forest. To propose the CCPi, the human impacts and richness of troglobiotic and troglophile species of 100 caves were associated. Data related to troglomorphic/troglobiotic fauna from another 200 caves were used to map the troglobiotic diversity and distribution. The CCPi reveals extremely high conservation priority for 15 % of the caves, high for 36 % and average for 46 % of the caves. Fourteen caves with extremely high priorities should have urgent conservation and management actions. The geographical distribution of the 221 known troglobiotic/troglomorphic species allowed us to select 19 karst areas that need conservation actions. Seven areas were considered to have urgent priority for conservation actions. The two richest areas correspond to the "iron quadrangle" with iron ore caves (67 spp.) and the "Açungui limestone group" (56 spp.). Both areas have several caves and are important aquifers. The use of the CCPi can prevent future losses because it helps assessors to select caves with priorities for conservation which should receive emergency attention in relation to protection, management and conservation actions.

  8. IMPACT OF TROPICAL RAIN FOREST CONVERSION ON THE DIVERSITY AND ABUNDANCE OF TERMITES IN JAMBI PROVINCE (Dampak Konversi Hutan Tropika Basah Terhadap Keragaman Jenis dan Kelimpahan Rayap di Provinsi Jambi

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    Suryo Hardiwinoto

    2010-03-01

    Full Text Available ABSTRACT The degradation of tropical rain forest might exert impacts on biodiversity loss and affect the function and stability of the ecosystems. The objective of this study was to clarify the impacts of tropical rain forests conversion into other land-uses on the diversity and abundance of termites in Jambi, Sumatera. Six land use types used in this study were primary forest, secondary forest, rubber plantation, oil-palm plantation, cassava cultivation and Imperata grassland. The result showed that a total of 30 termite species were found in the six land use types, with highest species richness and abundance in the forests. The species richness and the relative abundance of termites decreased significantly when the tropical rain forests were converted to rubber plantation and oil-palm plantation. The loss of species richness was much greater when the forests were changed to cassava cultivation and Imperata grassland, while their abundance greatly decreased when the forests were degraded to Imperata grassland. Termite species which had high relative abundances in primary and secondary forests were Dicuspiditermes nemorosus, Schedorhinotermes medioobscurus, Nasutitermes longinasus and Procapritermes setiger.   ABSTRAK  Kerusakan hutan tropika basah dapat menimbulkan dampak lingkungan berupa penurunan keanekaragaman hayati serta terganggunya fungsi dan stabilitas ekosistem. Tujuan dari penelitian ini adalah untuk mengetahui dampak konversi hutan tropika basah  menjadi bentuk penggunaan lahan lain di Jambi Sumatra terhadap keragaman jenis dan kelimpahan rayap. Enam tipe penggunaan lahan yang digunakan dalam penelitian ini adalah hutan primer, hutan sekunder, tanaman karet, tanaman kelapa sawit, kebun ketela pohon dan padang alang-alang. Hasil penelitian menunjukkan bahwa ditemukan 30 jenis rayap pada 6 tipe penggunaan lahan tersebut, dengan keragaman jenis dan kelimpahan individu rayap tertinggi pada lahan hutan. Kekayaan jenis dan kelimpahan

  9. Rain chemistry and cloud composition and microphysics in a Caribbean tropical montane cloud forest under the influence of African dust

    Science.gov (United States)

    Torres-Delgado, Elvis; Valle-Diaz, Carlos J.; Baumgardner, Darrel; McDowell, William H.; González, Grizelle; Mayol-Bracero, Olga L.

    2015-04-01

    It is known that huge amounts of mineral dust travels thousands of kilometers from the Sahara and Sahel regions in Africa over the Atlantic Ocean reaching the Caribbean, northern South America and southern North America; however, not much is understood about how the aging process that takes place during transport changes dust properties, and how the presence of this dust affects cloud's composition and microphysics. This African dust reaches the Caribbean region mostly in the summer time. In order to improve our understanding of the role of long-range transported African dust (LRTAD) in cloud formation processes in a tropical montane cloud forest (TMCF) in the Caribbean region we had field campaigns measuring dust physical and chemical properties in summer 2013, as part of the Puerto Rico African Dust and Cloud Study (PRADACS), and in summer 2014, as a part of the Luquillo Critical Zone Observatory (LCZO) and in collaboration with the Saharan Aerosol Long-Range Transport and Aerosol-Cloud-Interaction Experiment (SALTRACE). Measurements were performed at the TMCF of Pico del Este (PE, 1051 masl) and at the nature reserve of Cabezas de San Juan (CSJ, 60 masl). In both stations we monitored meteorological parameters (e.g., temperature, wind speed, wind direction). At CSJ, we measured light absorption and scattering at three wavelengths (467, 528 and 652 nm). At PE we collected cloud and rainwater and monitored cloud microphysical properties (e.g., liquid water content, droplet size distribution, droplet number concentration, effective diameter and median volume diameter). Data from aerosol models, satellites, and back-trajectories were used together with CSJ measurements to classify air masses and samples collected at PE in the presence or absence of dust. Soluble ions, insoluble trace metals, pH and conductivity were measured for cloud and rainwater. Preliminary results for summer 2013 showed that in the presence of LRTAD (1) the average conductivity of cloud water

  10. Importance of riparian remnants for frog species diversity in a highly fragmented rainforest.

    Science.gov (United States)

    Rodríguez-Mendoza, Clara; Pineda, Eduardo

    2010-12-23

    Tropical forests undergo continuous transformation to other land uses, resulting in landscapes typified by forest fragments surrounded by anthropogenic habitats. Small forest fragments, specifically strip-shaped remnants flanking streams (referred to as riparian remnants), can be particularly important for the maintenance and conservation of biodiversity within highly fragmented forests. We compared frog species diversity between riparian remnants, other forest fragments and cattle pastures in a tropical landscape in Los Tuxtlas, Mexico. We found similar species richness in the three habitats studied and a similar assemblage structure between riparian remnants and forest fragments, although species composition differed by 50 per cent. Frog abundance was halved in riparian remnants compared with forest fragments, but was twice that found in pastures. Our results suggest that riparian remnants play an important role in maintaining a portion of frog species diversity in a highly fragmented forest, particularly during environmentally stressful (hot and dry) periods. In this regard, however, the role of riparian remnants is complementary, rather than substitutive, with respect to the function of other forest fragments within the fragmented forest.

  11. A importância de Reservas Particulares do Patrimônio Natural para a conservação da brioflora da Mata Atlântica: um estudo em El Nagual, Magé, RJ, Brasil The importance of Private Natural Heritage Reserves for conservation of Atlantic rain forest bryoflora: a study at El Nagual, Magé, Rio de Janeiro State, Brazil

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    Nivea Dias dos Santos

    2008-06-01

    Full Text Available Foi realizado o levantamento das briófitas da RPPN El Nagual, uma área de floresta submontana no Estado do Rio de Janeiro. Foram registradas 137 espécies (um antócero, 70 hepáticas e 66 musgos e duas variedades, distribuídas em 75 gêneros e 37 famílias, sendo cinco novas ocorrências para o estado. Lejeuneaceae (27 spp., Pilotrichaceae (17 spp., Aneuraceae (9 spp. e Calymperaceae (8 spp. destacam-se pela riqueza de espécies (44% da brioflora. Sete formas de vida foram caracterizadas, predominando trama (37%, tufo (16% e talosa (15%. Seis tipos de substrato são colonizados na área, predominando espécies corticícolas (52% e rupícolas (42%. Em relação aos padrões de distribuição, predominaram espécies neotropicais e pantropicais. Foram encontradas quatro espécies caracterizadas como vulneráveis no estado. Os resultados demonstram que a brioflora da RPPN é rica e evidenciam a importância dessa categoria de unidade de conservação na proteção de remanescentes de Mata Atlântica e conservação da brioflora.A floristic survey of the bryophytes was carried out in the El Nagual Private Natural Heritage Reserve, a submontane Atlantic rain forest remnant in Rio de Janeiro state. One hundred and thirty seven species were recorded (one Anthocerotae, 70 hepatics and 66 mosses plus two varieties, in 75 genera and 37 families. Five species are new records for Rio de Janeiro state. Lejeuneaceae (27 spp., Pilotrichaceae (17 spp., Aneuraceae (9 spp., and Calymperaceae (8 spp. are especially rich in species (44% of the bryoflora. Seven life-forms were found; the most common are weft (37%, turf (16%, and thallose (15%. Six kinds of substrate were colonized, the most important species types being corticicolous (52% and rupicolous (42%. The most common distribution patterns were Neotropical and Pantropical. Four species were considered to be vulnerable in the state. The results show that the bryoflora of the El Nagual Reserve is relatively

  12. Remnant large 'rescue' trees enhance epiphyte resilience to anthropogenic disturbance of pine-oak forests in the Highlands of Chiapas, Mexico

    NARCIS (Netherlands)

    Wolf, J.H.D.

    2006-01-01

    I studied vascular epiphytes in 16 pine-oak forest fragments within an 400 km2 relatively flat area at c. 2300 m elevation on an extended gradient of anthropogenic disturbance. Epiphyte biomass and species richness on 35 oak host trees in six diameter classes varied between the sites from 0.8 to 243

  13. Communal nests of Hemidactylus mabouia (Moreau de Jonnès, 1818 (Squamata: Gekkonidae in a remnant of Atlantic Forest in northeastern Brazil

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    Pablo Augusto Gurgel de Sousa

    2010-09-01

    Full Text Available Communal nesting has been registered for several species of lizards. The egg aggregations offer potential advantages such as protection, predator-satiation and thermoregulation. Hemidactylus mabouia is a successful colonizing species with continuous reproduction and a fixed size of two eggs each time. Here, we report two communal nests of Hemidactylus mabouia for the Parque Estadual Mata da Pipa, Atlantic Forest of northeastern Brazil.

  14. Reptiles of forest remnants and agricultural fields on Cambuhy Farm, in the municipalities of Matão, Nova Europa, and Tabatinga, northwestern São Paulo, Brazil

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    Ana Bárbara Barros

    2017-02-01

    Full Text Available In São Paulo State, the northwestern region is the most deforested and has the lowest concentration of protected areas. Despite recent scientific advances, there are still gaps in the herpetological knowledge for this region. The objective of the present study was to provide information about richness, abundance and habitat use of reptiles on Cambuhy Farm, which is in the municipalities of Matão, Nova Europa, and Tabatinga. Sampling occurred from 2013 to 2015, and used four methods: pitfall traps, visual search limited by time, visual search on roads and occasional records. The study also included records from the literature and biological collections. We recorded 46 species of reptiles belonging to the Squamata and Crocodylia groups. The most common species were Salvator merianae (N = 55, the most abundant species in all study sites, Notomabuya frenata (N = 14, sampled only in the forests, and Ameiva ameiva (N = 4 that was recorded in anthropic and forest environments. The species composition recorded reflects the location of the study area, with the majority of species associated with the Cerrado and Atlantic Forest biomes. The richness of reptiles on Cambuhy Farm represents 21% of the richness in São Paulo, and is of great significance for the conservation of the herpetofauna in the northwestern region of the state.

  15. From the Guiana Highlands to the Brazilian Atlantic Rain Forest: four new species of Selaginella (Selaginellaceae – Lycopodiophyta: S. agioneuma, S. magnafornensis, S. ventricosa, and S. zartmanii

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    Iván A. Valdespino

    2018-05-01

    Full Text Available We describe four new species in the genus Selaginella (i.e., S. agioneuma, S. magnafornensis, S. ventricosa, and S. zartmanii from Brazil, all presently classified in subg. Stachygynandrum. For each of the new taxa we discuss taxonomic affinities and provide information on habitat, distribution, and conservation status. In addition, line drawings and scanning electron microscope (SEM images of stems sections, leaves, and spores (when present are included. Selaginella agioneuma and S. magnafornensis are from the State of Espíritu Santo where they inhabit premontane to montane Atlantic rain forests in the Reserva Biológica Augusto Ruschi and Parque Estadual Forno Grande, respectively. Selaginella ventricosa was collected in upper montane forests at Parque Nacional Serra da Mocidade, State of Roraima and S. zartmanii in premontane Amazon rain forests on upper Rio Negro at Mpio. São Gabriel da Cachoeira, Amazonas State in both Serra Curicuriari and the Morro dos Seis Lagos Biological Reserve.

  16. Evolution of Supernova Remnants

    Science.gov (United States)

    Arbutina, B.

    2017-12-01

    This book, both a monograph and a graduate textbook, is based on my original research and partly on the materials prepared earlier for the 2007 and 2008 IARS Astrophysics Summer School in Istanbul, AstroMundus course 'Supernovae and Their Remnants' that was held for the first time in 2011 at the Department of Astronomy, Faculty of Mathematics, University of Belgrade, and a graduate course 'Evolution of Supernova Remnants' that I teach at the aforementioned university. The first part Supernovae (introduction, thermonuclear supernovae, core-collapse supernovae) provides introductory information and explains the classification and physics of supernova explosions, while the second part Supernova remnants (introduction, shock waves, cosmic rays and particle acceleration, magnetic fields, synchrotron radiation, hydrodynamic and radio evolution of supernova remnants), which is the field I work in, is more detailed in scope i.e. technical/mathematical. Special attention is paid to details of mathematical derivations that often cannot be found in original works or available literature. Therefore, I believe it can be useful to both, graduate students and researchers interested in the field.

  17. Long-term observations of cloud condensation nuclei in the Amazon rain forest – Part 1: Aerosol size distribution, hygroscopicity, and new model parametrizations for CCN prediction

    Directory of Open Access Journals (Sweden)

    M. L. Pöhlker

    2016-12-01

    Full Text Available Size-resolved long-term measurements of atmospheric aerosol and cloud condensation nuclei (CCN concentrations and hygroscopicity were conducted at the remote Amazon Tall Tower Observatory (ATTO in the central Amazon Basin over a 1-year period and full seasonal cycle (March 2014–February 2015. The measurements provide a climatology of CCN properties characteristic of a remote central Amazonian rain forest site.The CCN measurements were continuously cycled through 10 levels of supersaturation (S  =  0.11 to 1.10 % and span the aerosol particle size range from 20 to 245 nm. The mean critical diameters of CCN activation range from 43 nm at S  =  1.10 % to 172 nm at S  =  0.11 %. The particle hygroscopicity exhibits a pronounced size dependence with lower values for the Aitken mode (κAit  =  0.14 ± 0.03, higher values for the accumulation mode (κAcc  =  0.22 ± 0.05, and an overall mean value of κmean  =  0.17 ± 0.06, consistent with high fractions of organic aerosol.The hygroscopicity parameter, κ, exhibits remarkably little temporal variability: no pronounced diurnal cycles, only weak seasonal trends, and few short-term variations during long-range transport events. In contrast, the CCN number concentrations exhibit a pronounced seasonal cycle, tracking the pollution-related seasonality in total aerosol concentration. We find that the variability in the CCN concentrations in the central Amazon is mostly driven by aerosol particle number concentration and size distribution, while variations in aerosol hygroscopicity and chemical composition matter only during a few episodes.For modeling purposes, we compare different approaches of predicting CCN number concentration and present a novel parametrization, which allows accurate CCN predictions based on a small set of input data.

  18. Soluble reactive phosphorus (SRP) transport and retention in tropical, rain forest streams draining a volcanic landscape in Costa Rica: In situ SRP amendment to streams and laboratory studies

    Science.gov (United States)

    Triska, F.; Pringle, C.M.; Duff, J.H.; Avanzino, R.J.; Zellweger, G.

    2006-01-01

    Soluble reactive phosphorus (SRP) transport/retention was determined in two rain forest streams (Salto, Pantano) draining La Selva Biological Station, Costa Rica. There, SRP levels can be naturally high due to groundwater enriched by geothermal activity within the surfically dormant volcanic landscape, and subsequently discharged at ambient temperature. Combined field and laboratory approaches simulated high but natural geothermal SRP input with the objective of estimating the magnitude of amended SRP retention within high and low SRP settings and determining the underlying mechanisms of SRP retention. First, we examined short-term SRP retention/transport using combined SRP-conservative tracer additions at high natural in situ concentrations. Second, we attempted to observe a DIN response during SRP amendment as an indicator of biological uptake. Third, we determined SRP release/retention using laboratory sediment assays under control and biologically inhibited conditions. Short-term in situ tracer-SRP additions indicated retention in both naturally high and low SRP reaches. Retention of added SRP mass in Upper Salto (low SRP) was 17% (7.5 mg-P m-2 h-1), and 20% (10.9 mg-P m-2 h -1) in Lower Salto (high SRP). No DIN response in either nitrate or ammonium was observed. Laboratory assays using fresh Lower Salto sediments indicated SRP release (15.4 ?? 5.9 ??g-P g dry wt.-1 h -1), when incubated in filter sterilized Salto water at ambient P concentration, but retention when incubated in filter sterilized river water amended to 2.0 mg SRP l-1 (233.2 ?? 5.8 ??g-P g dry wt. -1 h-1). SRP uptake/release was similar in both control- and biocide-treated sediments indicating predominantly abiotic retention. High SRP retention even under biologically saturated conditions, absence of a DIN response to amendment, patterns of desorption following amendment, and similar patterns of retention and release under control and biologically inhibited conditions all indicated

  19. Seasonal variation in the number of captures of Artibeus lituratus (Olfers, 1818 and Sturnira lilium (E. Geoffroy, 1810 (Chiroptera: Phyllostomidae in the upper strata of an Atlantic Forest remnant in southern Brazil

    Directory of Open Access Journals (Sweden)

    Fernando Carvalho

    2014-09-01

    Full Text Available This study aimed to analyze the occurrence of seasonal variations in the number of captures of Artibeus lituratus and Sturnira lilium in the upper strata of an Atlantic Forest remnant in southern Brazil. It was conducted in the town of Pedras Grandes, in the southern end of Santa Catarina. The chiropterans were captured with mist nets installed in the canopy and subcanopy. To check whether there were differences in the number of captures between seasons, we used the chi-square test (χ2, with a significance level of 0.05, and, whenever needed, partial χ2 tests. Artibeus lituratus showed significant differences between seasons, and the largest number of captures occurs in autumn. For S. lilium we did not observe statistically significant differences. The seasonal variation found out for A. lituratus may be related to its diet, which is based on fruits whose availability has seasonal variations. For S. lilium, besides the diet, mainly based on plants that do not have seasonal variations with regard to fruit availability, the altitude of the study area and its variations in temperature also seem to explain the absence of seasonal variation.

  20. Quantification of litter and nutrients on an Atlantic Rain Forest/ Quantificação de serapilheira e de nutrientes em uma Floresta Ombrófila Densa

    Directory of Open Access Journals (Sweden)

    Rafaelo Balbinot

    2008-08-01

    Full Text Available No matter what kind of forest it is, the litter production represents the first stage of nutrients and energy transfer from the vegetation to the soil, because most of the nutrients absorbed by the plants comes back to the forest ground through the fall of the litter or leaves wash. The aim of this study was to quantify the production of accumulated litter and nutrient contents on three successional stages of Atlantic Rain Forest, Blumenau/SC - Brazil. For the collections of the accumulated litter five rectangular samples units (SU of 10 m x 20 m were used in each successional stage, in a total of 15 SUs. In each SU the collections of material in an aleatory way was made with the aid of a metal frame of 0.25 m x 0.25 m, with five replications per SU every 30 days (75 samples/month, that is to say, 25 samples/successional stage. The average production of accumulated litter in twenty two months in the collected data was, in a decreasing order, stage III (5.28 Mg ha-1 > stage II (5.02 Mg ha-1 > stage I (4.47 Mg ha-1. The total macronutrient contents on accumulated litter of successional stages I and II, in decreasing order were: N > Ca > Mg > K > S > P, and on stage III: N > Ca > Mg > S > K > P. The forest presented total content of micronutrients on accumulated litter of three successional stages in the following decreasing order: Fe > Mn > Zn > B > Cu. For the total organic carbon content on accumulated litter, the sequence was: stage II (1.65 Mg ha-1 > stage III (1.50 Mg ha-1 > stage I (1.47 Mg ha-1.Seja qual for o tipo de floresta, a produção de serapilheira representa o primeiro estágio de transferência de nutrientes e energia da vegetação para o solo, pois a maior parte dos nutrientes absorvidos pelas plantas retorna ao piso florestal através da queda de serapilheira ou lavagem foliar. O objetivo desse estudo foi quantificar a produção de serapilheira acumulada e o conteúdo de nutrientes em três estádios sucessionais da Floresta

  1. Brazil-USA Collaborative Research: Modifications by Anthropogenic Pollution of the Natural Atmospheric Chemistry and Particle Microphysics of the Tropical Rain Forest During the GoAmazon Intensive Operating Periods (IOPs)

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Saewung [Univ. of California, Irvine, CA (United States)

    2017-08-01

    Manaus, a city of nearly two million people, represents an isolated urban area having a distinct urban pollution plume within the otherwise pristine Amazon Basin. The plume has high concentrations of oxides of nitrogen and sulfur, carbon monoxide, particle concentrations, and soot, among other pollutants. Critically, the distinct plume in the setting of the surrounding tropical rain forest serves as a natural laboratory to allow direct comparisons between periods of pollution influence to those of pristine conditions. The funded activity of this report is related to the Brazil-USA collaborative project during the two Intensive Operating Periods (wet season, 1 Feb - 31 Mar 2014; dry season, 15 Aug - 15 Oct 2014) of GoAmazon2014/5. The project addresses key science questions regarding the modification of the natural atmospheric chemistry and particle microphysics of the forest by present and future anthropogenic pollution.

  2. Industrial ecotoxicology "acid rain".

    Science.gov (United States)

    Astolfi, E; Gotelli, C; Higa, J

    1986-01-01

    The acid rain phenomenon was studied in the province of Cordoba, Argentina. This study, based on a previously outlined framework, determined the anthropogenic origin of the low pH due to the presence of industrial hydrochloric acid wastage. This industrial ecotoxicological phenomenon seriously affected the forest wealth, causing a great defoliation of trees and shrubs, with a lower effect on crops. A survey on its effects on human beings has not been carried out, but considering the corrosion caused to different metals and its denouncing biocide effect on plants and animals, we should expect to find some kind of harm to the health of the workers involved or others engaged in farming, and even to those who are far away from the polluting agent.

  3. Abundância e frugivoria da quiropterofauna (Mammalia, chiroptera de um fragmento no noroeste do Estado do Paraná, Brasil = Chiropterofauna abundance and frugivory in a forest remnant in northwestern Paraná State, Brazil

    Directory of Open Access Journals (Sweden)

    João Eduardo Cavalcanti Brito

    2010-07-01

    Full Text Available A abundância e a frugivoria de morcegos que compõem a taxocenose em uma área de mata ripária, à margem esquerda do rio Ivaí, foram foco do presente estudo. O Recanto Marista possui 57,6 hectares, dos quais 40,8 são cobertos por Floresta Estacional Semidecidual, situado no município de Doutor Camargo, região Noroeste do Estado do Paraná. Foram realizadas 14 noites de capturas de morcegos de maio de 2007 a janeiro de 2008, com redesneblina (7 x 2,5 m, totalizando 13.475 m² h de esforço amostral, distribuído em 72h de esforço. Foram capturados 193 indivíduos, representantes de dez espécies, pertencentes a duas famílias: Phyllostomidae (Artibeus lituratus, Sturnira lilium, Carollia perspicillata, Artibeus cf. fimbriatus, Artibeus planirotris, Desmodus rotundus e Pygoderma bilabiatum e Vespertilionidae (Myotis nigricans, Eptesicus sp. e Lasiurus blossevillii. Um representante da família Molossidae (Molossus rufus foi encontrado morto no solo. Foram consumidos frutos pertencentes às famílias Moraceae (Ficus guaranitica, Ficus insipida, Ficus sp. e Maclura tinctoria, Solanaceae (Solanum aspero-lanatum e Solanum sp., Piperaceae (Piper aduncum, Piper amalago e Piper sp. e Urticaceae (Cecropia pachystachya e Cecropia sp..This study aims to evaluate the abundance and frugivory of bats from the Recanto Marista, a small riparian forest remnant in the margins of the Ivaí river. The Recanto Marista has 57.6 ha, of which 40.8 ha are covered by semideciduous seasonal forest and is located in the Doutor Camargo municipality. Collections were conducted from May 2007to January 2008 using mist nets (7 x 2.5 m totaling 13,475 m² h and comprising about 72 hours. Ten species were found pertaining to two families, Phyllostomidae (Artibeus lituratus, Sturnira lilium, Carollia perspicillata, Artibeus cf. fimbriatus, Artibeus planirotris, Desmodus rotundus and Pygoderma bilabiatum and Vespertilionidae (Myotis nigricans, Eptesicus sp. and Lasiurus

  4. Pteridófitas de uma área remanescente de Floresta Atlântica do Estado de Pernambuco, Brasil Floristic survey of the pteridophytes from a remnant area of Atlantic Forest, Pernambuco State, Brazil

    Directory of Open Access Journals (Sweden)

    Sandra Tereza Ambrósio

    1997-12-01

    Full Text Available É apresentado um "checklist" das pteridófitas ocorrentes na Reserva Ecológica de Jangadinha, Município de Jaboatão dos Guararapes, como contribuição aos estudos da pteridoflora de áreas de Floresta Atlântica do Estado de Pernambuco. Informações sobre a auto-ecologia das espécies também são apresentadas. Coletas foram realizadas em cinco pontos, denominados de Banho-Frio -1, Banho-Frio - II, Área do Reservatório, Área do Açude e Mata do Curado. Foram reconhecidos 25 táxons distribuídos em 14 famílias: Schizaeaceae (2 spp., Gleicheniaceae (2 spp., Hymenophyllaceae (1 sp., Cyatheaceae (1 sp., Pteridaceae (7 spp., Vittariaceae (1 sp., Dennstaedtiaceae (2 spp., Thelypteridaceae (2 spp., Dryopteridaceae (1 sp., Davalliaceae (1 sp., Blechnaceae (1 sp., Polypodiaceae (2 spp., Lycopodiaceae (1 sp. e Selaginellaceae (1 sp.. Em todos os pontos de coletas há pteridófitas, sendo que Banho-Frio I é o mais rico e a Mata do Curado relativamente pobre em número de espécies. A maior diversidade florística foi encontrada nos micro-habitats de interior e margem das matas, principalmente em barrancos úmidos.A checklist of the pteridophytes occurrence in Ecological Reserve of Jangadinha, in the municipality of Jaboatão dos Guararapes was made as a contribution to the study of remnant area of Atlantic Forest of Pernambuco, Brazil. Auto-ecology information about the species are included. Collections were made in five points of the Reserve, namely Banho-Frio -1, Banho-Frio - II, Área do Açude, Área do Reservatório and Mata do Curado. Twenty-five species of the following 14 families were recognized: Schizaeaceae (2 spp., Gleicheniaceae (2 spp., Hymenophyllaceae (1 sp., Cyatheaceae (1 sp., Pteridaceae (7 spp., Vittariaceae (1 sp., Dennstaedtiaceae (2 spp., Thelypteridaceae (2 spp., Dryopteridaceae (1 sp., Davalliaceae (lsp., Blechnaceae (1 p., Polypodiaceae (2 spp., Lycopodiaceae (1 sp. and Selaginellaceae (1 sp.. Pteridophytes occurred in

  5. Forests

    Science.gov (United States)

    Louis R. Iverson; Mark W. Schwartz

    1994-01-01

    Originally diminished by development, forests are coming back: forest biomass is accumulating. Forests are repositories for many threatened species. Even with increased standing timber, however, biodiversity is threatened by increased forest fragmentation and by exotic species.

  6. Aves de três remanescentes florestais do norte do Estado do Paraná, sul do Brasil, com sugestões para a conservação e manejo Birds from three forest remnants in the North of Paraná State, South of Brazil, with suggestions for conservation and management

    Directory of Open Access Journals (Sweden)

    Marcos Ricardo Bornschein

    2000-09-01

    Full Text Available One hundred eighty species in a preliminary inventory were identified. From these, 166 were in an area of 832.5 ha (Mata São Francisco State Park, 84 in another of 9.7 ha (Manoel Júlio de Almeida Municipal Forest and 99 in the third remnant, briefly sampled, of 218 ha (Mata São Paulo. Comparing these numbers to inventories of nearby sites was considered that the larger area is poor in number of bird species, and believe this to be mainly due to the high degree of environmental degradation. Was considered that the smaller area is rich in birds, but its proximity (375 meters to the third remnant certainly exeits strong influence. This paper presents the list of birds by site and with their relative frequency of occurrence. A new record for Paraná (Scarlet-headed Blackbird Amblyramphus holosericeus, two new ones for the interior of the state (Uniform Crake Amaurolimnas concolor and Yellow-lored Tody-flycatcher Todirostrum poliocephalum and several other important records are commented (e.g. Red-legged Seriema Cariama cristata, Vinaceous Parrot Amazona vinacea, and Black-banded Owl Ciccaba huhula. Locally extinct species are discussed (e.g. Harpy Eagle Harpia harpyja, as well as the ones that colonized landscapes created by men (e.g. pastures, agricultural areas. When discussing Atlantic Forest endemism, some species were shown not to be endemic to this biome. Because the north of Paraná is almost totally deforested, the presence of the forest remnants by itself conter them great importance for conservation, besides the existence of species endemic to the Atlantic Forest and considered to be under the threat of extinction. Conservation and management measures are also proposed.

  7. Bat use of remnant old-growth redwood stands

    Science.gov (United States)

    William J. Zielinski; Steven T. Gellman

    1999-01-01

    Most of the old-growth redwood (Sequoia sempervirens) in Calfornia has been cut; regenerating forests will probably never resemble those that were harvested, and what old growth remains on private land occurs in small, isolated remnant patches. The landscapes in which these stands occur differ so markedly from their original condition that their...

  8. Rain Gauges Handbook

    Energy Technology Data Exchange (ETDEWEB)

    Bartholomew, M. J. [Brookhaven National Lab. (BNL), Upton, NY (United States)

    2016-01-01

    To improve the quantitative description of precipitation processes in climate models, the Atmospheric Radiation Measurement (ARM) Climate Research Facility deployed rain gauges located near disdrometers (DISD and VDIS data streams). This handbook deals specifically with the rain gauges that make the observations for the RAIN data stream. Other precipitation observations are made by the surface meteorology instrument suite (i.e., MET data stream).

  9. Acid Rain Study Guide.

    Science.gov (United States)

    Hunger, Carolyn; And Others

    Acid rain is a complex, worldwide environmental problem. This study guide is intended to aid teachers of grades 4-12 to help their students understand what acid rain is, why it is a problem, and what possible solutions exist. The document contains specific sections on: (1) the various terms used in conjunction with acid rain (such as acid…

  10. Understanding Acid Rain

    Science.gov (United States)

    Damonte, Kathleen

    2004-01-01

    The term acid rain describes rain, snow, or fog that is more acidic than normal precipitation. To understand what acid rain is, it is first necessary to know what an acid is. Acids can be defined as substances that produce hydrogen ions (H+), when dissolved in water. Scientists indicate how acidic a substance is by a set of numbers called the pH…

  11. The Acid Rain Reader.

    Science.gov (United States)

    Stubbs, Harriett S.; And Others

    A topic which is often not sufficiently dealt with in elementary school textbooks is acid rain. This student text is designed to supplement classroom materials on the topic. Discussed are: (1) "Rain"; (2) "Water Cycle"; (3) "Fossil Fuels"; (4) "Air Pollution"; (5) "Superstacks"; (6) "Acid/Neutral/Bases"; (7) "pH Scale"; (8) "Acid Rain"; (9)…

  12. Agaricales em áreas de Floresta Ombrófila Densa e plantações de Pinus no Estado de Santa Catarina, Brasil Agaricales in Atlantic rain forest and Pinus plantations in Santa Catarina State, Brazil

    Directory of Open Access Journals (Sweden)

    Fernanda Karstedt

    2008-12-01

    Full Text Available Os sistemas florestais de Santa Catarina são poucos estudados em relação à diversidade de Agaricales. O objetivo deste trabalho foi determinar e comparar a diversidade de Agaricales em dois sistemas florestais, no município de Joinville, SC. Parcelas de 20×20 m foram estabelecidas: três em Floresta Ombrófila Densa e três em plantações de Pinus. Basidiomas de fungos agaricóides foram coletados em janeiro, março, maio, julho, setembro e novembro/2004. Foram identificadas 40 espécies, 31 na Floresta e 10 nas plantações. A família mais representada foi Tricholomataceae, com 48% das espécies registradas na Floresta. As espécies com maior abundância relativa foram Camarophyllus buccinulus (41% na Floresta e Lactarius cf. fragilis (53% nas plantações. As mesmas espécies foram também as mais freqüentes, com 44% e 78% de freqüência de ocorrência, respectivamente. Considerando a riqueza de espécies e o índice de diversidade de Shannon, o estudo sugere que há maior diversidade de Agaricales na Floresta do que nas plantações de Pinus.Forest systems in Santa Catarina state are virtually unknown regarding Agaricales diversity. Our goal was to determine and compare the Agaricales diversity of two forest systems in Joinville municipality, SC. Plots of 20×20 m were established: three in the Atlantic rain forest and three in Pinus plantations. Basidiomata of Agaricales were collected in January, March, May, July, September and November/2004. Forty species were identified, 31 in the forest and 10 in the plantations. Tricholomataceae was the most important family, with 48% of the species found in the forest. The species with the highest relative abundance were Camarophyllus buccinulus (41% and Lactarius cf. fragilis (53% in the forest and in the plantations, respectively. These were also the most frequent species recovered in the forest and in the plantations, with frequency values of 44% and 78%, respectively. Considering species

  13. PROGENITORS OF RECOMBINING SUPERNOVA REMNANTS

    Energy Technology Data Exchange (ETDEWEB)

    Moriya, Takashi J., E-mail: takashi.moriya@ipmu.jp [Kavli Institute for the Physics and Mathematics of the Universe, Todai Institutes for Advanced Study, University of Tokyo, Kashiwanoha 5-1-5, Kashiwa, Chiba 277-8583 (Japan)

    2012-05-01

    Usual supernova remnants have either ionizing plasma or plasma in collisional ionization equilibrium, i.e., the ionization temperature is lower than or equal to the electron temperature. However, the existence of recombining supernova remnants, i.e., supernova remnants with ionization temperature higher than the electron temperature, has been recently confirmed. One suggested way to have recombining plasma in a supernova remnant is to have a dense circumstellar medium at the time of the supernova explosion. If the circumstellar medium is dense enough, collisional ionization equilibrium can be established in the early stage of the evolution of the supernova remnant and subsequent adiabatic cooling, which occurs after the shock wave gets out of the dense circumstellar medium, makes the electron temperature lower than the ionization temperature. We study the circumstellar medium around several supernova progenitors and show which supernova progenitors can have a circumstellar medium dense enough to establish collisional ionization equilibrium soon after the explosion. We find that the circumstellar medium around red supergiants (especially massive ones) and the circumstellar medium dense enough to make Type IIn supernovae can establish collisional ionization equilibrium soon after the explosion and can evolve to become recombining supernova remnants. Wolf-Rayet stars and white dwarfs have the possibility to be recombining supernova remnants but the fraction is expected to be very small. As the occurrence rate of the explosions of red supergiants is much higher than that of Type IIn supernovae, the major progenitors of recombining supernova remnants are likely to be red supergiants.

  14. Consequences of habitat fragmentation on genetic structure of Chamaedorea alternans (Arecaceae) palm populations in the tropical rain forests of Los Tuxtlas, Veracruz, Mexico

    OpenAIRE

    Peñaloza-Ramírez, Juan Manuel; Aguilar-Amezquita, Bernardo; Núñez-Farfán, Juan; Pérez-Nasser, Nidia; Albarrán-Lara, Ana Luisa; Oyama, Ken

    2016-01-01

    Abstract: Chamaedorea alternans is a palm species that has suffered from selective extraction, and habitat loss. We collected 11 populations from fragmented and conserved forest. We assess genetic variation of C. alternans, genetic exchange, differentiation, bottlenecks, effective population size and signals of natural selection. Genetic diversity was higher in conserved than in fragmented forest but not significant. Fragmentation did not play a significant role in genetic diversity, possibly...

  15. Seed germination responses in a temperate rain forest of Chiloé, Chile: effects of a gap and the tree canopy

    OpenAIRE

    Figueroa, Javier A; Hernández, Juan F

    2001-01-01

    This study determined germination responses of 19 species, including trees, shrubs, vines, and herbs, under natural gap and non-gap conditions, in a secondary forest in Chiloé Island, southern Chile, in order to assess if there is any association between the habitat where the seedlings of these plant species occur and their germination requirements. Statistical differences in percentage seed germination were detected in six species in a gap habitat compared to the understory. Five forest edge...

  16. Acidification and Acid Rain

    Science.gov (United States)

    Norton, S. A.; Veselã½, J.

    2003-12-01

    endangers the existing biota. Concerns about acid (or acidic) rain in its modern sense were publicized by the Swedish soil scientist Svante Odén (1968). He argued, initially in the Swedish press, that long-term increases in the atmospheric deposition of acid could lower the pH of surface waters, cause a decline in fish stocks, deplete soils of nutrients, and accelerate damage to materials. By the 1970s, acidification of surface waters was reported in many countries in Europe as well as in North America. The late twentieth-century rush to understand the impact of acid rain was driven by: (i) reports of damaged or threatened freshwater fisheries and (ii) damaged forests. Perhaps the earliest linkage between acidic surface water and damage to fish was made by Dahl (1921) in southern Norway. There, spring runoff was sufficiently acidic to kill trout. It was not until the 1970s that a strong link was established between depressed pH, mobilization of aluminum from soil, and fish status ( Schofield and Trojnar,1980). The relationship between acidification of soils and forest health started with hypotheses in the 1960s and has slowly developed. Acid rain enhances the availability of some nutrients (e.g., nitrogen), and may either enhance or diminish the availability of others (e.g., calcium, magnesium, potassium, and phosphorus). Damage to anthropogenic structures, human health, and visibility have also raised concerns. The history of these early developments was summarized by Cowling (1982). Since the 1970s, sulfur and nitrogen emissions to the atmosphere have been reduced by 50-85% and 0-30%, respectively, both in North America and Europe. The emission reductions have occurred as a consequence of knowledge gained and economic factors. While recovery of water quality is underway in some areas, problems of acidification persist, and are now complicated by the effects of climate change ( Schindler, 1997).

  17. Remnants of Lost Geology

    Science.gov (United States)

    2003-01-01

    [figure removed for brevity, see original site] In eastern Arabia Terra, remnants of a once vast layered terrain are evident as isolated buttes, mesas, and deeply-filled craters. The origin of the presumed sediments that created the layers is unknown, but those same sediments, now eroded, may be the source of the thick mantle of dust that covers much of Arabia Terra today.Note: this THEMIS visual image has not been radiometrically nor geometrically calibrated for this preliminary release. An empirical correction has been performed to remove instrumental effects. A linear shift has been applied in the cross-track and down-track direction to approximate spacecraft and planetary motion. Fully calibrated and geometrically projected images will be released through the Planetary Data System in accordance with Project policies at a later time.NASA's Jet Propulsion Laboratory manages the 2001 Mars Odyssey mission for NASA's Office of Space Science, Washington, D.C. The Thermal Emission Imaging System (THEMIS) was developed by Arizona State University, Tempe, in collaboration with Raytheon Santa Barbara Remote Sensing. The THEMIS investigation is led by Dr. Philip Christensen at Arizona State University. Lockheed Martin Astronautics, Denver, is the prime contractor for the Odyssey project, and developed and built the orbiter. Mission operations are conducted jointly from Lockheed Martin and from JPL, a division of the California Institute of Technology in Pasadena.Image information: VIS instrument. Latitude 20.5, Longitude 50 East (310 West). 19 meter/pixel resolution.

  18. Plantas medicinais de um remascente de Floresta Ombrófila Mista Altomontana, Urupema, Santa Catarina, Brasil Medicinal plants in a remnant of High Montane Araucaria Moist Forest, Urupema Municipality, Santa Catarina State, Brazil

    Directory of Open Access Journals (Sweden)

    D. Martins-Ramos

    2010-09-01

    Full Text Available O objetivo deste trabalho foi pesquisar dados químicos, biológicos e etnobotânicos na literatura científica de espécies medicinais de um remanescente de Floresta Ombrófila Mista Altomontana. A base para este estudo foi um levantamento florístico realizado na Fazenda das Nascentes, Urupema-SC entre agosto de 2007 e setembro de 2008. A partir da lista de espécies que resultou deste levantamento, foi realizada uma revisão bibliográfica sobre o potencial medicinal das espécies inventariadas. Para as espécies com dados de ação medicinal, foi elaborada chave de identificação vegetativa. Das 64 espécies listadas foram encontradas informações na bibliografia consultada sobre o potencial medicinal de 29. As principais familias foram Asteraceae (oito espécies e Myrtaceae (três espécies. O hábito que mais se destacou entre as plantas com potencial medicinal foi o arbóreo (13 espécies. O componente químico de maior ocorrência entre as espécies foi o óleo essencial (60% das espécies. As atividades terapêuticas mais citadas na literatura consultadas foram antimicrobiana, anti-oxidante, anti-inflamatória, antiviral, antifúngica e anestésica. Os resultados encontrados indicam o imenso potencial econômico da Floresta Ombrófila Mista e ambientes associados como fonte de recursos naturais que fazem parte da cultura e do patrimônio catarinense.The aim of this work was to search for chemical, biological and ethnobotanical data in the scientific literature on medicinal species from a remnant of High Montane Araucaria Moist Forest. This study was based on the floristics performed in "Fazenda das Nascentes", Urupema Municipality, Santa Catarina State, Brazil between August 2007 and September 2008. From the list of species obtained in this survey, a review on the medicinal potential of these recorded species was done. A vegetative identification key was elaborated for species with medicinal action Information about medicinal

  19. Challenges and difficulties in service to legal requirements applicable to a pipeline works at the Amazon rain forest, Brazil; Os desafios e dificuldades no atendimento aos requisitos legais aplicaveis a uma obra na Amazonia

    Energy Technology Data Exchange (ETDEWEB)

    Freitas, Wanderleia I.P. de [Universidade do Estado do Amazonas (UEA), Manaus, AM (Brazil); Freitas, Jaluza G.M.R. de; Teixeira, Ivan J.L. [Concremat Engenharia e Tecnologia, Rio de Janeiro, RJ (Brazil)

    2008-07-01

    This work brings together the difficulties and results generated in response to Brazilian Environmental Law applicable to a work of pipelines in the Amazon. We are a country that has the most extensive and rich environmental legislation in the world, and Engineering at PETROBRAS, through the Implementation of Enterprise for the North, responsible for the deployment of this pipeline, has ISO 14001:2004 certification, taking as the minimum requirement attending the applicable legal requirements, and serve them in if there are difficulties elsewhere in the country, here in the Amazon it is increased meet the logistical difficulties, the distances from major centres, the needs of technology, information and access to basic resources. This article discusses topics such as: transport of hazardous waste in an environmentally safe way in one of the largest rivers in the world, installing devices sewage treatment in regional boats, and teach the riparian preserve the historic and archaeological findings, these are just examples found. We know that all eyes of the world is impressive return to the Amazon rain forest, and that cross, or rather 'rip' their 383 km of primary forest, virgin land, almost untouched even by the people native of the region, in itself constitutes a great challenge. (author)

  20. Growth and mortality patterns in a thinning canopy of post-hurricane regenerating rain forest in eastern Nicaragua (1990-2005

    Directory of Open Access Journals (Sweden)

    Javier Ruiz

    2010-12-01

    Full Text Available One of the strongest hypothesis about the maintenance of tree species diversity in tropical areas is disturbance. In order to assess this, the effect of intensive natural disturbances on forest growth and mortality in a thinning canopy was studied after the landfall of hurricane Joan in 1988. We evaluated the growth and mortality rates of the 26 most common tree species of that forest in eastern Nicaragua. Permanent plots were established at two study sites within the damaged area. Growth and mortality rates of all individual trees ≥3.18cm diameter at breast height were assessed annually from 1990 to 2005. During this period the forest underwent two phases: the building phase (marked by increased number of individuals of tree species present after the hurricane and the canopy thinning phase (marked by increased competition and mortality. Our results from the thinning phase show that tree survival was independent of species identity and was positively related to the increase in growth rates. The analysis of mortality presented here aims to test the null hypothesis that individual trees die independently of their species identity. These findings were influenced by the mortality observed during the late thinning phase (2003-2005 and provide evidence in favor of a non-niche hypothesis at the thinning phase of forest regeneration. Rev. Biol. Trop. 58 (4: 1283-1297. Epub 2010 December 01.

  1. USGS Tracks Acid Rain

    Science.gov (United States)

    Gordon, John D.; Nilles, Mark A.; Schroder, LeRoy J.

    1995-01-01

    The U.S. Geological Survey (USGS) has been actively studying acid rain for the past 15 years. When scientists learned that acid rain could harm fish, fear of damage to our natural environment from acid rain concerned the American public. Research by USGS scientists and other groups began to show that the processes resulting in acid rain are very complex. Scientists were puzzled by the fact that in some cases it was difficult to demonstrate that the pollution from automobiles and factories was causing streams or lakes to become more acidic. Further experiments showed how the natural ability of many soils to neutralize acids would reduce the effects of acid rain in some locations--at least as long as the neutralizing ability lasted (Young, 1991). The USGS has played a key role in establishing and maintaining the only nationwide network of acid rain monitoring stations. This program is called the National Atmospheric Deposition Program/National Trends Network (NADP/NTN). Each week, at approximately 220 NADP/NTN sites across the country, rain and snow samples are collected for analysis. NADP/NTN site in Montana. The USGS supports about 72 of these sites. The information gained from monitoring the chemistry of our nation's rain and snow is important for testing the results of pollution control laws on acid rain.

  2. Riqueza e distribuição espaço-temporal de anuros em um remanescente de Floresta de Araucária no sudeste do Paraná Anuran richness and spatial-temporal distribution along an Araucária Forest remnant in southeastern Paraná State, Brazil

    Directory of Open Access Journals (Sweden)

    Carlos E. Conte

    2007-12-01

    Full Text Available A riqueza de espécies, a distribuição espacial e a ocorrência sazonal de anuros (adultos e girinos foram determinadas ao longo de 15 meses, em um remanescente da floresta de araucária no município de Fazenda Rio Grande, Paraná, Brasil. Foram registradas 32 espécies, sendo essa a área com a terceira maior riqueza registrada no Estado. A distribuição espacial das espécies não foi uniforme entre os hábitats amostrados: 46% das espécies foram associadas à área aberta, ocorrendo exclusivamente em hábitats de área aberta e/ou em borda florestal, 34% foram associadas à hábitats florestais, ocorrendo em hábitats florestais ou de borda florestal, enquanto que 13% foram classificadas como generalistas, pois ocorreram em área aberta, borda e interior de floresta. O período reprodutivo dos anuros foi fortemente relacionado com a chuvosa, quando cerca de 80% das espécies foram registradas em atividade de vocalização. Cerca de 40% das espécies registradas são associadas à hábitats florestais, o que reforça a urgência da preservação desses remanescentes de Floresta de Araucária.Species richness, spatial distribution and the seasonal occurrence of anurans (adults and tadpoles were studied throughout 15 months in an Araucaria forest remnant at Fazenda Rio Grande, Paraná State, Brazil. Thirty-two species were registered, which corresponds to the third largest anuran richness in Paraná State. The spatial distribution of the species was not uniform between habitats sampled: 46% of the species were associates with opened areas, occurring exclusively in habitats of open areas and/or in forest edges, 34% were associated with forest habitats, occurring, in habitats forest and/or forest edge, while that 13% were classified as generalists as they occurred in open formations, at the edge and interior of the forest fragments. The reproductive period of the species was correlated with rainfall, since 80% of the species were found in

  3. Local-scale spatial variation in diversity of social wasps in an Amazonian rain forest in Caxiuanã, Pará, Brazil (Hymenoptera, Vespidae, Polistinae

    Directory of Open Access Journals (Sweden)

    Orlando Tobias Silveira

    2012-09-01

    Full Text Available Polistine wasps are important in Neotropical ecosystems due to their ubiquity and diversity. Inventories have not adequately considered spatial attributes of collected specimens. Spatial data on biodiversity are important for study and mitigation of anthropogenic impacts over natural ecosystems and for protecting species. We described and analyzed local-scale spatial patterns of collecting records of wasp species, as well as spatial variation of diversity descriptors in a 2500-hectare area of an Amazon forest in Brazil. Rare species comprised the largest fraction of the fauna. Close range spatial effects were detected for most of the more common species, with clustering of presence-data at short distances. Larger spatial lag effects could also be identified in some species, constituting probably cases of exogenous autocorrelation and candidates for explanations based on environmental factors. In a few cases, significant or near significant correlations were found between five species (of Agelaia, Angiopolybia, and Mischocyttarus and three studied environmental variables: distance to nearest stream, terrain altitude, and the type of forest canopy. However, association between these factors and biodiversity variables were generally low. When used as predictors of polistine richness in a linear multiple regression, only the coefficient for the forest canopy variable resulted significant. Some level of prediction of wasp diversity variables can be attained based on environmental variables, especially vegetation structure. Large-scale landscape and regional studies should be scheduled to address this issue.

  4. Postprandial Hyperlipidemia and Remnant Lipoproteins.

    Science.gov (United States)

    Masuda, Daisaku; Yamashita, Shizuya

    2017-02-01

    Fasting hypertriglyceridemia is positively associated with the morbidity of coronary heart disease (CHD), and postprandial (non-fasting) hypertriglyceridemia is also correlated with the risk status for CHD, which is related to the increase in chylomicron (CM) remnant lipoproteins produced from the intestine. CM remnant particles, as well as oxidized low density lipoprotein (LDL) or very low density lipoprotein (VLDL) remnants, are highly atherogenic and act by enhancing systemic inflammation, platelet activation, coagulation, thrombus formation, and macrophage foam cell formation. The cholesterol levels of remnant lipoproteins significantly correlate with small, dense LDL; impaired glucose tolerance (IGT) and CHD prevalence. We have developed an assay of apolipoprotein (apo)B-48 levels to evaluate the accumulation of CM remnants. Fasting apoB-48 levels correlate with the morbidity of postprandial hypertriglyceridemia, obesity, type III hyperlipoproteinemia, the metabolic syndrome, hypothyroidism, chronic kidney disease, and IGT. Fasting apoB-48 levels also correlate with carotid intima-media thickening and CHD prevalence, and a high apoB-48 level is a significant predictor of CHD risk, independent of the fasting TG level. Diet interventions, such as dietary fibers, polyphenols, medium-chain fatty acids, diacylglycerol, and long-chain n-3 polyunsaturated fatty acids (PUFA), ameliorate postprandial hypertriglyceridemia, moreover, drugs for dyslipidemia (n-3 PUFA, statins, fibrates or ezetimibe) and diabetes concerning incretins (dipeptidyl-peptidase IV inhibitor or glucagon like peptide-1 analogue) may improve postprandial hypertriglyceridemia. Since the accumulation of CM remnants correlates to impaired lipid and glucose metabolism and atherosclerotic cardiovascular events, further studies are required to investigate the characteristics, physiological activities, and functions of CM remnants for the development of new interventions to reduce atherogenicity.

  5. Heavy rain effects

    Science.gov (United States)

    Dunham, R. Earl, Jr.

    1994-01-01

    This paper summarizes the current state of knowledge of the effect of heavy rain on airplane performance. Although the effects of heavy rain on airplane systems and engines are generally known, only recently has the potential aerodynamic effect of heavy rain been recognized. In 1977 the United States Federal Aviation Administration (FAA) conducted a study of 25 aircraft accidents and incidents which occurred between 1964 and 1976 in which low-altitude wind shear could have been a contributing factor. Of the 25 cases (23 approach or landing and 2 take-off) in the study, ten cases had occurred in a rain environment, and in five cases these were classified as intense or heavy rain encounters. These results led to the reconsideration of high-intensity, short-duration rainfall as a potential weather-related aircraft safety hazard, particularly in the take-off and/or approach phases of flight.

  6. Natural and near natural tropical forest values

    Science.gov (United States)

    Daniel H. Henning

    2011-01-01

    This paper identifies and describes some of the values associated with tropical rain forests in their natural and near-natural conditions. Tropical rain forests are moist forests in the humid tropics where temperature and rainfall are high and the dry season is short. These closed (non-logged) and broad-leaved forests are a global resource. Located almost entirely in...

  7. The Green Ocean Amazon Experiment (GoAmazon2014/5) Observes Pollution Affecting Gases, Aerosols, Clouds, and Rainfall over the Rain Forest

    Energy Technology Data Exchange (ETDEWEB)

    Martin, S. T. [Harvard University, Cambridge, Massachusetts; Artaxo, P. [University of São Paulo, São Paulo, Brazil; Machado, L. [National Institute for Space Research, São José dos Campos, Brazil; Manzi, A. O. [National Institute of Amazonian Research, Manaus, Amazonas, Brazil; Souza, R. A. F. [Amazonas State University, Amazonas, Brazil; Schumacher, C. [Texas A& amp,M University, College Station, Texas; Wang, J. [Brookhaven National Laboratory, Upton, New York; Biscaro, T. [National Institute for Space Research, São José dos Campos, Brazil; Brito, J. [University of São Paulo, São Paulo, Brazil; Calheiros, A. [National Institute for Space Research, São José dos Campos, Brazil; Jardine, K. [Lawrence Berkeley National Lab, Berkeley, California; Medeiros, A. [Amazonas State University, Amazonas, Brazil; Portela, B. [National Institute of Amazonian Research, Manaus, Amazonas, Brazil; de Sá, S. S. [Harvard University, Cambridge, Massachusetts; Adachi, K. [Meteorological Research Institute, Tsukuba, Ibaraki, Japan; Aiken, A. C. [Los Alamos National Laboratory, Los Alamos, New Mexico; Albrecht, R. [University of São Paulo, São Paulo, Brazil; Alexander, L. [Pacific Northwest National Laboratory, Richland, Washington; Andreae, M. O. [Max Planck Institute for Chemistry, Mainz, Germany; Barbosa, H. M. J. [University of São Paulo, São Paulo, Brazil; Buseck, P. [Arizona State University, Tempe, Arizona; Chand, D. [Pacific Northwest National Laboratory, Richland, Washington; Comstock, J. M. [Pacific Northwest National Laboratory, Richland, Washington; Day, D. A. [University of Colorado Boulder, Boulder, Colorado; Dubey, M. [Los Alamos National Laboratory, Los Alamos, New Mexico; Fan, J. [Pacific Northwest National Laboratory, Richland, Washington; Fast, J. [Pacific Northwest National Laboratory, Richland, Washington; Fisch, G. [Aeronautic and Space Institute, São José dos Campos, Brazil; Fortner, E. [Aerodyne, Inc., Billerica, Massachusetts; Giangrande, S. [Brookhaven National Laboratory, Upton, New York; Gilles, M. [Lawrence Berkeley National Lab, Berkeley, California; Goldstein, A. H. [University of California, Berkeley, Berkeley, California; Guenther, A. [University of California, Irvine, Irvine, California; Hubbe, J. [Pacific Northwest National Laboratory, Richland, Washington; Jensen, M. [Brookhaven National Laboratory, Upton, New York; Jimenez, J. L. [University of Colorado Boulder, Boulder, Colorado; Keutsch, F. N. [Harvard University, Cambridge, Massachusetts; Kim, S. [University of California, Irvine, Irvine, California; Kuang, C. [Brookhaven National Laboratory, Upton, New York; Laskin, A. [Pacific Northwest National Laboratory, Richland, Washington; McKinney, K. [Harvard University, Cambridge, Massachusetts; Mei, F. [Pacific Northwest National Laboratory, Richland, Washington; Miller, M. [Rutgers, The State University of New Jersey, New Brunswick, New Jersey; Nascimento, R. [Amazonas State University, Amazonas, Brazil; Pauliquevis, T. [Federal University of São Paulo, São Paulo, Brazil; Pekour, M. [Pacific Northwest National Laboratory, Richland, Washington; Peres, J. [University of São Paulo, São Paulo, Brazil; Petäjä, T. [University of Helsinki, Helsinki, Finland; Pöhlker, C. [Max Planck Institute for Chemistry, Mainz, Germany; Pöschl, U. [Max Planck Institute for Chemistry, Mainz, Germany; Rizzo, L. [Federal University of São Paulo, São Paulo, Brazil; Schmid, B. [Pacific Northwest National Laboratory, Richland, Washington; Shilling, J. E. [Pacific Northwest National Laboratory, Richland, Washington; Dias, M. A. Silva [University of São Paulo, São Paulo, Brazil; Smith, J. N. [University of California, Irvine, Irvine, California; Tomlinson, J. M. [Pacific Northwest National Laboratory, Richland, Washington; Tóta, J. [Federal University of West Para, Santarém, Pará, Brazil; Wendisch, M. [University of Leipzig, Leipzig, Germany

    2017-05-01

    The Observations and Modeling of the Green Ocean Amazon (GoAmazon2014/5) experiment took place around the urban region of Manaus in central Amazonia across two years. The urban pollution plume was used to study the susceptibility of gases, aerosols, clouds, and rainfall to human activities in a tropical environment. Many aspects of air quality, weather, terrestrial ecosystems, and climate work differently in the tropics than in the more thoroughly studied USA, employed an unparalleled suite of measurements at nine ground sites and onboard two aircraft to investigate the flow of background air into Manaus, the emissions into the air over the city, and the advection of the pollution downwind of the city. Herein, to visualize this train of processes and its effects, observations aboard a low-flying aircraft are presented. Comparative measurements within and adjacent to the plume followed the emissions of biogenic volatile organic carbon compounds (BVOCs) from the tropical forest, their transformations by the atmospheric oxidant cycle, alterations of this cycle by the influence of the pollutants, transformations of the chemical products into aerosol particles, the relationship of these particles to cloud condensation nuclei (CCN) activity, and the differences in cloud properties and rainfall for background compared to polluted conditions. The observations of the GoAmazon2014/5 experiment illustrate how the hydrologic cycle, radiation balance, and carbon recycling may be affected by present-day as well as future economic development and pollution over the Amazonian tropical forest.

  8. Chuva de sementes em Floresta Estacional Semidecidual em Viçosa, MG, Brasil Seed rain in a seasonal semideciduous forest at Viçosa, Minas Gerais State, Brazil

    Directory of Open Access Journals (Sweden)

    Érica Pereira de Campos

    2009-06-01

    Full Text Available Este estudo objetivou avaliar a composição florística, a densidade e a freqüência de sementes, em 25 coletores, em um trecho de Floresta Estacional Semidecidual. Além disso, classificar os táxons quanto à forma de vida, às síndromes de dispersão e, nas arbóreas, quanto ao estádio sucessional e verificar a similaridade florística entre as espécies identificadas na chuva de sementes e as espécies arbóreas localizadas nas mesmas parcelas dos coletores. O trabalho foi realizado entre dezembro/2004 a novembro/2006. Foram reconhecidos 43 táxons, sendo que Leguminosae foi representada por 11 espécies. A forma de vida dominante foi arbórea (63,1%, as lianas foram representadas por 28,9% das espécies amostradas, as herbáceas por 5,3% e as arbustivas por 2,6%. A densidade média de sementes no primeiro ano foi de 113,92 sementes.m-2 e no segundo de 2.603,84 sementes.m-2. Essas diferenças demonstraram heterogeneidade espacial e temporal da chuva de sementes. A similaridade florística encontrada pelo índice de Sørensen entre as espécies da chuva de sementes e as espécies arbóreas do trecho do fragmento estudado foi de 32%, valor considerado baixo (This study aims to evaluate the floristic composition, density and frequency of seeds in 25 traps in a section of seasonal semideciduous forest, as well as classify taxons as to life form, dispersal syndromes, and succession phase of the tree species, and verify floristic similarities between seed rain species and tree species located in the same plots. The work was carried out from December/2004 to November/2006. Forty three taxons were recognized and Leguminosae was represented by 11 species. The dominant life form was arboreal (63.1%, climbers were represented by 28.9% of the sampled species, herbs by 5.3% and shrubs by 2.6%. Mean seed density in the first year was 113.92 seeds.m-2 and 2603.84 seeds.m-2 in the second year. These differences showed spatial and seasonal heterogeneity

  9. Brazil-USA Collaborative Research: Modifications by Anthropogenic Pollution of the Natural Atmospheric Chemistry and Particle Microphysics of the Tropical Rain Forest During the GoAmazon Intensive Operating Periods (IOPs)

    Energy Technology Data Exchange (ETDEWEB)

    Jimenez, Jose-Luis [Univ. of Colorado, Boulder, CO (United States); Day, Douglas A. [Univ. of Colorado, Boulder, CO (United States); Martin, Scot T. [Univ. of Colorado, Boulder, CO (United States); Kim, Saewung [Univ. of Colorado, Boulder, CO (United States); Smith, James [Univ. of Colorado, Boulder, CO (United States); Souza, Rodrigo [Univ. of Colorado, Boulder, CO (United States); Barbosa, Henry [Univ. of Colorado, Boulder, CO (United States)

    2017-08-04

    Manaus, a city of nearly two million people, represents an isolated urban area having a distinct urban pollution plume within the otherwise pristine Amazon Basin. The plume has high concentrations of oxides of nitrogen and sulfur, carbon monoxide, particle concentrations, and soot, among other pollutants. Critically, the distinct plume in the setting of the surrounding tropical rain forest serves as a natural laboratory to allow direct comparisons between periods of pollution influence to those of pristine conditions. The funded activity of this report is related to the Brazil-USA collaborative project during the two Intensive Operating Periods (wet season, 1 Feb - 31 Mar 2014; dry season, 15 Aug - 15 Oct 2014) of GoAmazon2014/5. The project addresses key science questions regarding the modification of the natural atmospheric chemistry and particle microphysics of the forest by present and future anthropogenic pollution. The first objective of the project was to understand and quantify the interactions of biogenic and anthropogenic emissions with respect to the production of secondary organic material. In clean conditions in the Amazon basin, secondary organic material dominates the diameter distribution of the submicron particles. How and why is the diameter distribution shifted by pollution? The second objective followed from the first in that, although the diameter distribution is dominated by secondary organic material, the actual source of new particle production remains uncertain (i.e., the number concentration). The second objective was to test the hypothesis that new particles under natural conditions are produced as a result of evaporation of primary particles emitted by fungal spores as well as to investigate any shifts in this mechanism under pollution conditions, e.g., in consequence to the high concentrations of SO2 in the pollution plume. Combined, the number-diameter distribution is the key connection to upscaling to the effects of aerosol

  10. A vegetação secundária em um fragmento florestal urbano: influência de exóticas invasoras na comunidade vegetal. Secondary vegetation in a urban forest remnant: alien species influence on plant community

    Directory of Open Access Journals (Sweden)

    Silvana Cristina Pereira Muniz de SOUZA

    2016-06-01

    urbanization. However, some small reserves protected by laws still sustain natural vegetation remnants.This work was developed in one of these reserves the Alberto Löfgren State Park – PEAL. We aimed to detect the successional stage of secondary vegetation of PEAL and check the influence of alien species in the successional process.We conducted a phytosociological survey in a 4.8 ha continuous forest patch, where 30 plots of 20 x 20 m were randomly distributed and individual shrubs and trees with a perimeter at breast height – PBH ≥ 15 cm were sampled. A total of 121 species (35 exotic, belonging to 102 genera and 44 families were recorded. Eleven species were categorized as endangered. The Shannon diversity and the Pielou equability indexes were 3.38 and 0.70 respectively, and the total density was 1,400 ind.ha-1. Half of the 12 species of highest importance value was alien species. We concluded that PEAL has a high degree of biological invasion, which may cause serious damage to the natural succession process in areas under recovery. In order to prevent the spread of alien species into the natural forests of Cantareira Range, we recommend the adoption of an integrated program that includes the alien species control and regional native species enrichment if needed. In this work we indicated the exotic species that should be managed first in order to restore the ecological sucession.

  11. Primeiro registro de Aedes albopictus em área da Mata Atlântica, Recife, PE, Brasil First report of Aedes albopictus in areas of rain forest in Brazil

    Directory of Open Access Journals (Sweden)

    Cleide MR de Albuquerque

    2000-06-01

    Full Text Available Pela primeira vez é registrada a presença do Aedes albopictus em remanescentes de Mata Atlântica, localizada em área urbana em Recife (Pernambuco, Brasil. As coletas foram realizadas em isca humana e em criadouros de formas jovens (ocos de árvores, bambus, bromélias e pneu. A presença de Ae. albopictus na região metropolitana do Recife representa um risco potencial do inter-relacionamento dessa espécie de mosquito com a população.This is the first report of the presence of Aedes albopictus in the native rain forest, near the urban area of Recife (State of Pernambuco, Brazil. Adult female mosquitoes were collected using human bait. Mosquitoes in aquatic stages were looked for in treeholes, bamboos, bromeliads and old tires. The existence of Ae. albopictus in the metropolitan area of Recife poses a potential risk for the interaction of this mosquito species with the urban human population.

  12. Effect of a major highway on the spatial and temporal variation in the structure and diversity of the avifauna of a tropical premontane rain forest.

    Science.gov (United States)

    Avalos, Gerardo; Bermúdez, Esteban

    2016-12-01

    Roads immersed in conservation areas will increase in number, size, and traffic over the next decade, and thus, understanding their effects on forest-dependent wildlife is crucial for improving current management practices and reducing the negative impacts of roads on sensitive species. We examined the influence of route 32 (a.k.a. Guápiles Highway) on temporal and spatial changes in the structure of the avifauna of Braulio Carrillo National Park, Costa Rica, a site crossed by this road along 25 km. The highway connects the capital city of San José with the Harbor of Limón in the Caribbean Sea (142 km). Although the road is narrow (12 m in width and comprised by two lanes along most of the route) it services over 1.5 million motor vehicles per year, 12 % are heavy trucks and trailers. We expected the highway to divide the avifauna, and thus to observe significant differences in species structure on opposite sides of the road. We described changes in bird diversity between wet and dry seasons at Las Palmas and Ceibo trails located on opposite sides of the highway (14 point counts per trail), and evaluated how abundance and diversity varied with road distance. Censuses took place during wet and dry seasons from 2002 to 2005. We listed 245 species and 6 035 observations during the 4-yr survey. Rare species dominated the avifauna (65 % of species forests near the road. This highway will expand outside the National Park (from 2 to 4 lanes along 107 km from Río Frío to Limón) in the next years, which will increase traffic volume and road impacts within the Park. Roads are increasing across highly diverse tropical areas justifying the need for management practices based on the identification of sensitive groups.

  13. Effects of field plot size on prediction accuracy of aboveground biomass in airborne laser scanning-assisted inventories in tropical rain forests of Tanzania.

    Science.gov (United States)

    Mauya, Ernest William; Hansen, Endre Hofstad; Gobakken, Terje; Bollandsås, Ole Martin; Malimbwi, Rogers Ernest; Næsset, Erik

    2015-12-01

    Airborne laser scanning (ALS) has recently emerged as a promising tool to acquire auxiliary information for improving aboveground biomass (AGB) estimation in sample-based forest inventories. Under design-based and model-assisted inferential frameworks, the estimation relies on a model that relates the auxiliary ALS metrics to AGB estimated on ground plots. The size of the field plots has been identified as one source of model uncertainty because of the so-called boundary effects which increases with decreasing plot size. Recent research in tropical forests has aimed to quantify the boundary effects on model prediction accuracy, but evidence of the consequences for the final AGB estimates is lacking. In this study we analyzed the effect of field plot size on model prediction accuracy and its implication when used in a model-assisted inferential framework. The results showed that the prediction accuracy of the model improved as the plot size increased. The adjusted R 2 increased from 0.35 to 0.74 while the relative root mean square error decreased from 63.6 to 29.2%. Indicators of boundary effects were identified and confirmed to have significant effects on the model residuals. Variance estimates of model-assisted mean AGB relative to corresponding variance estimates of pure field-based AGB, decreased with increasing plot size in the range from 200 to 3000 m 2 . The variance ratio of field-based estimates relative to model-assisted variance ranged from 1.7 to 7.7. This study showed that the relative improvement in precision of AGB estimation when increasing field-plot size, was greater for an ALS-assisted inventory compared to that of a pure field-based inventory.

  14. Thinking in the Rain.

    Science.gov (United States)

    Bartlett, Albert A.

    1989-01-01

    Four questions related to rain concerning aerodynamic drag force, pressure from the impact of raindrops, impact of wind on the pressure, and stopping force extended on the car by the water are proposed. (YP)

  15. Estrutura arbórea da Floresta Ombrófila Densa Altomontana de serras do Sul do Brasil Tree component structure of tropical upper montane rain forests in Southern Brazil

    Directory of Open Access Journals (Sweden)

    Maurício Bergamini Scheer

    2011-12-01

    Full Text Available O presente trabalho teve os objetivos de agrupar informações sobre a estrutura arbórea da floresta altomontana da Serra do Mar paranaense e de compará-las com as de florestas altomontanas de outras serras do Sul e Sudeste do Brasil. Foram realizados levantamentos fitossociológicos em diversas montanhas de quatro importantes serras (ou subserras do Paraná. Nas quatro subserras foram amostrados 2294 indivíduos (PAP > 10 cm pertencentes a 28 famílias, 43 gêneros e 78 espécies. Foi observada maior riqueza de espécies na amostragem da Serra Gigante (41 espécies, seguida pelas serras da Prata (37, da Igreja (34 e do Ibitiraquire (26. A altura média obtida para os indivíduos foi de 4,8 m, o PAP médio de 22,9 cm, a densidade média de 4779 ind/ha, a área basal média de 33,5 m²/ha e o índice de diversidade de Shannon total de 2,68 nat/ind. Agrupando informações de estudos realizados em outras subserras paranaenses, totalizando 11 levantamentos e 204 parcelas (10200 m², obteve-se uma matriz com 75 espécies determinadas, onde as cinco com maior porcentagem de importância estrutural foram Ilex microdonta, Siphoneugena reitzii, Drimys angustifolia, Ocotea porosa e Ilex chamaedrifolia. Os trechos amostrados na Serra do Mar do Paraná, apresentaram menor riqueza e diversidade que os da Serra da Mantiqueira (MG e maior que os dos Aparados da Serra Geral (SC. Tais diferenças, possivelmente, estão relacionadas às influências antrópicas, das distâncias geográficas, dos diferentes centros de endemismo, dos entornos tropicais ou subtropicais dominantes, das feições geomorfológicas, entre outros fatores.The aims of this study were: (1 to group information about the tree structure of the upper montane rain forest of Serra do Mar in the state of Paraná (PR, Southern Brazil; and (2 to compare this information with available data from other mountain ranges in Southern and Southeastern Brazil. In the four mountain ranges studied, 2294

  16. Forests

    International Nuclear Information System (INIS)

    Melin, J.

    1997-01-01

    Forests have the capacity to trap and retain radionuclides for a substantial period of time. The dynamic behaviour of nutrients, pollution and radionuclides in forests is complex. The rotation period of a forest stand in the Nordic countries is about 100 years, whilst the time for decomposition of organic material in a forest environment can be several hundred years. This means that any countermeasure applied in the forest environment must have an effect for several decades, or be reapplied continuously for long periods of time. To mitigate the detrimental effect of a contaminated forest environment on man, and to minimise the economic loss in trade of contaminated forest products, it is necessary to understand the mechanisms of transfer of radionuclides through the forest environment. It must also be stressed that any countermeasure applied in the forest environment must be evaluated with respect to long, as well as short term, negative effects, before any decision about remedial action is taken. Of the radionuclides studied in forests in the past, radiocaesium has been the main contributor to dose to man. In this document, only radiocaesium will be discussed since data on the impact of other radionuclides on man are too scarce for a proper evaluation. (EG)

  17. Multi-scale Visualization of Remote Sensing and Topographic Data of the Amazon Rain Forest for Environmental Monitoring of the Petroleum Industry.

    Science.gov (United States)

    Fonseca, L.; Miranda, F. P.; Beisl, C. H.; Souza-Fonseca, J.

    2002-12-01

    PETROBRAS (the Brazilian national oil company) built a pipeline to transport crude oil from the Urucu River region to a terminal in the vicinities of Coari, a city located in the right margin of the Solimoes River. The oil is then shipped by tankers to another terminal in Manaus, capital city of the Amazonas state. At the city of Coari, changes in water level between dry and wet seasons reach up to 14 meters. This strong seasonal character of the Amazonian climate gives rise to four distinct scenarios in the annual hydrological cycle: low water, high water, receding water, and rising water. These scenarios constitute the main reference for the definition of oil spill response planning in the region, since flooded forests and flooded vegetation are the most sensitive fluvial environments to oil spills. This study focuses on improving information about oil spill environmental sensitivity in Western Amazon by using 3D visualization techniques to help the analysis and interpretation of remote sensing and digital topographic data, as follows: (a) 1995 low flood and 1996 high flood JERS-1 SAR mosaics, band LHH, 100m pixel; (b) 2000 low flood and 2001 high flood RADARSAT-1 W1 images, band CHH, 30m pixel; (c) 2002 high flood airborne SAR images from the SIVAM project (System for Surveillance of the Amazon), band LHH, 3m pixel and band XHH, 6m pixel; (d) GTOPO30 digital elevation model, 30' resolution; (e) Digital elevation model derived from topographic information acquired during seismic surveys, 25m resolution; (f) panoramic views obtained from low altitude helicopter flights. The methodology applied includes image processing, cartographic conversion and generation of value-added product using 3D visualization. A semivariogram textural classification was applied to the SAR images in order to identify areas of flooded forest and flooded vegetation. The digital elevation models were color shaded to highlight subtle topographic features. Both datasets were then converted to

  18. Haloacetates in fog and rain.

    Science.gov (United States)

    Römpp, A; Klemm, O; Fricke, W; Frank, H

    2001-04-01

    Atmospheric haloacetates can arise from photochemical degradation of halogenated hydrocarbons and from direct anthropogenic emissions. Furthermore, there is also evidence of natural sources although these are quantitatively uncertain. As haloacetates are highly soluble in water, hydrometeors are most significant for their deposition. Fogwater (96 samples) and rainwater samples (over 100 samples) were collected from July 1998 to March 1999 at an ecological research site in northeastern Bavaria, Germany. They were analyzed for monofluoroacetate (MFA), difluoroacetate (DFA), trifluoroacetate (TFA), monochloroacetate (MCA), dichloroacetate (DCA), trichloroacetate (TCA), monobromoacetate (MBA), and dibromoacetate (DBA). The major inorganic ions were also determined. High concentrations of up to 11 microg/L MCA, 5 microg/L DCA, 2 microg/L TCA, and 2 microg/L TFA were found in fogwater associated with westerly winds. Backward trajectories were calculated to determine the origin of the air masses. MBA and DBA have highest concentrations in fogwater advected with air originating from the Atlantic, suggesting the marine origin of these two compounds. All analyzed substances show higher average concentrations in fog than in rain. Estimates of the deposition of haloacetates suggest that the contribution of fog may be more important than rain for the total burden of a forest ecosystem.

  19. Estrutura da vegetação arbórea de um remanescente ecotonal urbano floresta-savana no Parque do Sabiá, em Uberlândia, MG Tree vegetation structure in an urban forest-savanna ecotone remnant, southeastern Brazil

    Directory of Open Access Journals (Sweden)

    Frederico Augusto Guimarães Guilherme

    2007-04-01

    Full Text Available Neste estudo, avaliou-se a estrutura do componente arbóreo de manchas de vegetação correspondentes à Floresta Estacional Semidecidual e dois cerradões, inseridas em um remanescente urbano composto também por uma mancha de mata de brejo. O levantamento compreendeu 1,32 ha, onde todos os indivíduos com perímetro à altura do peito > 5 cm foram amostrados. Registraram-se 141 espécies, distribuídas em 46 famílias botânicas, com diversidade de Shannon de 3,99. Fabaceae apresentou a maior riqueza de espécies no levantamento, corroborando o padrão encontrado em outros estudos sobre o bioma Cerrado. Maprounea guianensis teve os maiores valores relativos de densidade, freqüência e dominância no remanescente. A floresta estacional apresentou a maior riqueza florística e espécies características dessa formação, em comparação com demais pesquisas. Hirtella glandulosa apresentou o maior valor de importância no cerradão 2, o que evidencia a existência de um solo distrófico nessa fisionomia. Características estruturais similares entre o cerradão 2 e a floresta estacional e diversidade florística significativamente maior no cerradão 2 do que no cerradão 1, além da presença de espécies típicas de matas de brejo e floresta estacional no cerradão 2, evidenciavam áreas de transição no remanescente. No cerradão 1 foram registrados poucos indivíduos arbóreos nas menores classes de diâmetro. Isso provavelmente se deva às perturbações antrópicas constantes e variadas, indicando a necessidade de ações preventivas para a conservação e manejo desse patrimônio biológico.The study evaluated the tree component structure of vegetation fragments consisted of semideciduous forest, two woody savannas (cerradão, inserted in an urban forest remnant, also consisting of a fragment of swamp forest. The survey comprised 1.32 hectares, where all trees with ³ 5 cm perimeter at breast height were recorded. A total of 141 species

  20. Einstein Observations of Galactic supernova remnants

    Science.gov (United States)

    Seward, Frederick D.

    1990-01-01

    This paper summarizes the observations of Galactic supernova remnants with the imaging detectors of the Einstein Observatory. X-ray surface brightness contours of 47 remnants are shown together with gray-scale pictures. Count rates for these remnants have been derived and are listed for the HRI, IPC, and MPC detectors.

  1. HI Absorption in Merger Remnants

    Science.gov (United States)

    Teng, Stacy H.; Veileux, Sylvain; Baker, Andrew J.

    2012-01-01

    It has been proposed that ultraluminous infrared galaxies (ULIRGs) pass through a luminous starburst phase, followed by a dust-enshrouded AGN phase, and finally evolve into optically bright "naked" quasars once they shed their gas/dust reservoirs through powerful wind events. We present the results of our recent 21- cm HI survey of 21 merger remnants with the Green Bank Telescope. These remnants were selected from the QUEST (Quasar/ULIRG Evolution Study) sample of ULIRGs and PG quasars; our targets are all bolometrically dominated by AGN and sample all phases of the proposed ULIRG -> IR-excess quasar -> optical quasar sequence. We explore whether there is an evolutionary connection between ULIRGs and quasars by looking for the occurrence of HI absorption tracing neutral gas outflows; our results will allow us to identify where along the sequence the majority of a merger's gas reservoir is expelled.

  2. Molecular clouds near supernova remnants

    International Nuclear Information System (INIS)

    Wootten, H.A.

    1978-01-01

    The physical properties of molecular clouds near supernova remnants were investigated. Various properties of the structure and kinematics of these clouds are used to establish their physical association with well-known remmnants. An infrared survey of the most massive clouds revealed embedded objects, probably stars whose formation was induced by the supernova blast wave. In order to understand the relationship between these and other molecular clouds, a control group of clouds was also observed. Excitation models for dense regions of all the clouds are constructed to evaluate molecular abundances in these regions. Those clouds that have embedded stars have lower molecular abundances than the clouds that do not. A cloud near the W28 supernova remnant also has low abundances. Molecular abundances are used to measure an important parameter, the electron density, which is not directly observable. In some clouds extensive deuterium fractionation is observed which confirms electron density measurements in those clouds. Where large deuterium fractionation is observed, the ionization rate in the cloud interior can also be measured. The electron density and ionization rate in the cloud near W28 are higher than in most clouds. The molecular abundances and electron densities are functions of the chemical and dynamical state of evolution of the cloud. Those clouds with lowest abundances are probably the youngest clouds. As low-abundance clouds, some clouds near supernova remnants may have been recently swept from the local interstellar material. Supernova remnants provide sites for star formation in ambient clouds by compressing them, and they sweep new clouds from more diffuse local matter

  3. Inventário estruturado de formigas (Hymenoptera, Formicidae em floresta ombrófila de encosta na ilha da Marambaia, RJ Structured inventory of ants (Hymenoptera, Formicidae in atlantic slope rain-forest of Marambaia Island, RJ

    Directory of Open Access Journals (Sweden)

    Michel de S. Schütte

    2007-03-01

    Full Text Available As formigas são componentes funcionais importantes em florestas tropicais devido aos papéis ecológicos que exercem, à grande biomassa e à riqueza de espécies. Embora a Mata Atlântica seja um dos ecossistemas mais bem estudados no Brasil, ainda faltam informações sobre a diversidade de formigas nos fragmentos florestais do Estado do Rio de Janeiro. A riqueza e composição da assembléia de formigas em floresta ombrófila de encosta na ilha da Marambaia (RJ foi estudada através de um inventário estruturado em uma área de 0,6 ha. Armadilhas do tipo "pitfall" e coletas manuais foram empregadas na serapilheira e sobre a vegetação entre os meses de janeiro e julho de 2004. Um total de 29 gêneros e 82 espécies foi encontrado na amostragem. A abundância e a riqueza de espécies foram maiores nas amostras de março do que de julho. Já a eqüitatividade e diversidade de formigas nas amostras não foram influenciadas pela época da coleta. As amostras de formigas em galhos mortos adicionaram seis espécies à lista, acrescentando informações sobre a biologia das espécies. As amostras sobre plantas totalizaram 32 espécies de formigas, das quais 12 foram exclusivas, como as espécies de Pseudomyrmex e algumas de Crematogaster e Pachycondyla. Este estudo pretende contribuir para o desenvolvimento de prioridades conservacionistas em um dos ecossistemas mais ameaçados do mundo.Ants are an important functional component in tropical forest due to their ecological roles, biomass and species diversity. Although the Atlantic Forest is one of the best studied ecosystems in Brazil, there is a lack of information about ant diversity in forest fragments of the state of Rio de Janeiro. The composition and richness of the ant fauna from atlantic slope rain-forest in Marambaia island-RJ were assessed by the structured inventory in an area of 0.6 ha. Pitfalls traps and hand collecting were used for sampling ants in the litter and on vegetation from

  4. Visitantes florais do maracujá-amarelo (Passiflora edulis f. flavicarpa Deg. Passifloraceae em áreas de cultivo com diferentes proximidades a fragmentos florestais na região Norte Fluminense, RJ Yellow passion fruit (Passiflora edulis f. flavicarpa Deg. Passifloraceae floral visitors in cultivated areas within different distances from forest remnants in north Rio de Janeiro state

    Directory of Open Access Journals (Sweden)

    Cristine Rodrigues Benevides

    2009-01-01

    Full Text Available Este trabalho teve como objetivos estudar a biologia floral e identificar os principais polinizadores do maracujá-amarelo em áreas de cultivo com diferentes proximidades a fragmentos florestais no norte do estado do Rio de Janeiro. A floração do maracujá-amarelo teve duração de nove meses, no período de setembro a maio. As flores iniciavam a antese às 12:00 h e abriam-se ao longo do dia até às 16:30 h. O processo de curvatura dos estiletes ocorreu ao longo da antese e 72,4% das flores curvaram seus estiletes. A produção de néctar deu-se continuamente, atingindo 18μl/flor/hora e a concentração de solutos totais variou entre 38 e 42%. Xylocopa frontalis e Xylocopa ordinaria foram os principais polinizadores do maracujá-amarelo pela freqüência de visitas, comportamento intrafloral e porte corporal. Estas espécies de abelhas, além de Apis mellifera, estiveram presentes em todas as áreas de cultivo. A maior riqueza de visitantes polinizadores do maracujá-amarelo foi observada em áreas de cultivo próximas a fragmentos florestais, fato relacionado à presença de certos grupos de abelhas nativas, como Centridini e Euglossina (Apidae que dependem de áreas florestais para nidificação e alimentação. A proximidade a fragmentos florestais também é importante para o fornecimento de recursos alimentares e de nidificação ao longo do ano para a manutenção de populações de Xylocopa.This work aimed to identify the main pollinators and study the floral biology of the yellow passion fruit cultivated in areas within different distances from forest remnants in north Rio de Janeiro state. The yellow passion fruit flowering lasted nine months, from September to March. Anthesis started at 12:00 h and the opening process lasted until 16:30 h. The styles bent down during the anthesis and 72.4% of the flowers had its styles curved. Nectar was produced continuously, reaching 18μl/flower/hour, and the total solute concentration varied

  5. Drosophilidae (Diptera associated to fungi: differential use of resources in anthropic and Atlantic Rain Forest areas Drosophilidae (Diptera associados a fungos: uso diferenciado de recursos em áreas antrópicas e de Mata Atlântica

    Directory of Open Access Journals (Sweden)

    Marco S Gottschalk

    2009-12-01

    Full Text Available This study investigates the Drosophilidae species associated to fruiting bodies of fungi in forested and anthropized environments of the Atlantic Rain Forest Biome, in south and southeastern Brazil. We collected samples of imagoes flying over and emerging from fruiting bodies of species of five fungi families, in six collection sites. We obtained 18 samples, from which emerged 910 drosophilids of 31 species from the genera Drosophila Fallen, 1823, Hirtodrosophila Duda, 1923, Leucophenga Mik, 1886, Mycodrosophila Oldenberg, 1914, Scaptomyza Hardy, 1849, Zaprionus Coquillett, 1901 and Zygothrica Wiedemann, 1830. The Drosophila species collected on fungi, as well as Zaprionus indianus Gupta, 1970, had previously been recorded colonizing fruits, demonstrating their versatility in resource use. Most of these species belong to the immigrans-tripunctata radiation of Drosophila. Our records expands the mycophagous habit (feeding or breeding on fungi to almost all species groups of this radiation in the Neotropical region, even those supposed to be exclusively frugivorous. Assemblages associated to fungi of forested areas were more heterogeneous in terms of species composition, while those associated to fungi of anthropized areas were more homogeneous. The drosophilids from anthropized areas were also more versatile in resource use.Foi realizado um estudo das espécies de Drosophilidae associadas aos corpos de frutificação de fungos em ambientes florestais e antrópicos no Bioma Mata Atlântica, no sul e sudeste do Brasil. Foram realizadas coletas de adultos sobrevoando e emergindo de corpos de frutificação de espécies de fungos de cinco famílias, em seis pontos de coleta. Foram obtidas 18 amostras, onde foram coletados 910 indivíduos de 31 espécies, pertencentes aos gêneros Drosophila Fallen, 1823, Hirtodrosophila Duda, 1923, Leucophenga Mik, 1886, Mycodrosophila Oldenberg, 1914, Scaptomyza Hardy, 1849, Zaprionus Coquillett, 1901 e Zygothrica

  6. Weighing Rain Gauge Recording Charts

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Weighing rain gauge charts record the amount of precipitation that falls at a given location. The vast majority of the Weighing Rain Gauge Recording Charts...

  7. When It Rains, It Pours

    Science.gov (United States)

    Mills, Linda

    2012-01-01

    "It's raining, it's pouring, the old man is snoring!" "The itsy, bitsy spider crawled up the waterspout, down came the rain and washed the spider out. Out came the sun and dried up all the rain, and the itsy, bitsy spider went up the spout again." What do children's nursery rhymes have to do with the school library? The author begins by telling a…

  8. The urban perspectives of acid rain

    International Nuclear Information System (INIS)

    Tonn, B.E.

    1993-01-01

    This report documents discussions held during a workshop an Urban Perspective of Acid Rain. The workshop was sponsored by the Office of the Director, National Acid Precipitation Assessment Program (NAPAP). NAPAP anticipates giving increased emphasis to the benefits in urban areas of emissions reductions. The goal of this informal, exploratory workshop was to serve as a first step towards identifying pollutant monitoring, and research and assessment needs to help answer, from an urban perspective, the two key questions posed to NAPAP by Congress: (1) what are the costs, benefits, and effectiveness of the acid rain control program, and (2) what reductions in deposition, rates are needed in order to prevent adverse effects? The workshop addressed research activities needed to respond to these questions. The discussions focused. sequentially, on data needs, data and model availability, and data and modeling gaps. The discussions concentrated on four areas of effects: human health, materials, urban forests, and visibility

  9. Remnant cholesterol and ischemic heart disease

    DEFF Research Database (Denmark)

    Varbo, Anette; Nordestgaard, Børge G

    2014-01-01

    PURPOSE OF REVIEW: To review recent advances in the field of remnant cholesterol as a contributor to the development of ischemic heart disease (IHD). RECENT FINDINGS: Epidemiologic, mechanistic, and genetic studies all support a role for elevated remnant cholesterol (=cholesterol in triglyceride......-rich lipoproteins) as a contributor to the development of atherosclerosis and IHD. Observational studies show association between elevated remnant cholesterol and IHD, and mechanistic studies show remnant cholesterol accumulation in the arterial wall like LDL-cholesterol (LDL-C) accumulation. Furthermore, large...... genetic studies show evidence of remnant cholesterol as a causal risk factor for IHD independent of HDL-cholesterol levels. Genetic studies also show that elevated remnant cholesterol is associated with low-grade inflammation, whereas elevated LDL-C is not. There are several pharmacologic ways of lowering...

  10. Neutron Stars in Supernova Remnants and Beyond

    Science.gov (United States)

    Gvaramadze, V. V.

    We discuss a concept of off-centred cavity supernova explosion as applied to neutron star/supernova remnant associations and show how this concept could be used to preclude the anti-humane decapitating the Duck (G5.4-1.2 + G5.27-0.9) and dismembering the Swan (Cygnus Loop), as well as to search for a stellar remnant associated with the supernova remnant RCW86.

  11. Neutron Stars in Supernova Remnants and Beyond

    OpenAIRE

    Gvaramadze, V. V.

    2002-01-01

    We discuss a concept of off-centred cavity supernova explosion as applied to neutron star/supernova remnant associations and show how this concept could be used to preclude the anti-humane decapitating the Duck (G5.4-1.2 + G5.27-0.9) and dismembering the Swan (Cygnus Loop), as well as to search for a stellar remnant associated with the supernova remnant RCW86.

  12. Moessbauer study of corrosion induced by acid rain

    International Nuclear Information System (INIS)

    Arshed, M.; Hussain, N.; Siddiqui, M.; Anwar-ul-Islam, M.; Rehman, S.; Butt, N.M.

    1997-01-01

    Strictly speaking acid rain refers to wet precipitation of pollutants S0/sub 2/SO/sub 3/ and NO/sub x/HNO/sub 3/ which have dissolved in cloud and rain droplets to from sulphuric and nitric acids. Acid rain has seriously damaged pine and spruce forests in Canada, USA and Europe. In these areas it has caused damage to buildings, reduced fish population due to acidification of lakes and rivers, and affected health of human beings as a result of poor water quality. The corrosion products formed in a simulated acid rain environment have been identified with transmission Moessbauer spectroscopy using a /sup 57/Co source. They were found to be gamma-FeOOH, alpha-FeOOH, gamma-Fe/sub 2/O/sub 3/ and a phase with unfamiliar parameters which seems to be amorphous in nature and can be considered as an intermediate phase. (author)

  13. Forest vegetation of Xishuangbanna, south China

    Institute of Scientific and Technical Information of China (English)

    Zhu Hua

    2006-01-01

    Xishuangbanna of southern Yunnan is biogeographically located at a transitional zone from tropical southeast (SE) Asia to subtropical east Asia and is at the junction of the Indian and Burmese plates of Gondwana and the Eurasian plate of Laurasia. The region, though surprisingly far from the equator and at a relatively high altitude, has a rich tropical flora and a typical tropical rain forest in the lowland areas. Based on physiognomic and ecological characteristics, floristic composition and habitats combined, the primary vegetation in Xishuangbanna can be organized into four main vegetation types: tropical rain forest, tropical seasonal moist forest, tropical montane evergreen broad-leaved forest and tropical monsoon forest. The tropical rain forest can be classified into two subtypes, i.e. a tropical seasonal rain forest in the lowlands and a tropical montane rain forest at higher elevations. The tropical seasonal rain forest has almost the same forest profile and physiognomic characteristics as equatorial lowland rain forests and is a type of truly tropical rain forest. Because of conspicuous similarity on ecological and floristic characteristics, the tropical rain forest in Xishuangbanna is a type of tropical Asian rain forest. However, since the tropical rain forest of Xishuangbanna occurs at the northern edge of tropical SE Asia, it differs from typical lowland rain forests in equatorial areas in having some deciduous trees in the canopy layer, fewer megaphanerophytes and epiphytes but more abundant lianas and more plants with microphyll. It is a type of semi-evergreen rain forest at the northern edge of the tropical zone. The tropical montane rain forest occurs at wet montane habitats and is similar to the lower montane rain forest in equatorial Asia in floristic composition and physiognomy. It is a type of lower montane rain forests within the broader category of tropical rain forests. The tropical seasonal moist forest occurs on middle and upper

  14. Dynamical study of merger remnants

    International Nuclear Information System (INIS)

    Lake, G.; Dressler, A.; ATandT Bell Labs., Murray Hill, NJ; Mount Wilson and Las Campanas Observatories, Pasadena, CA; Carnegie Institution of Washington, Washington, DC)

    1986-01-01

    The velocity dispersion of objects from the Arp and the Arp-Madore atlases that have characteristics of recently merged galaxies is measured. These data are used to test the hypothesis that the remnants become normal elliptical galaxies after the fireworks of recent star formation subside. Accurate velocity dispersions of objects dominated by Balmer lines in the blue were measured using the uncontaminated Ca triplet feature in the extreme red (8400-8700 A). No deviation from the velocity dispersion expected for elliptical galaxies of comparable luminosity, is found, e.g., these systems follow the usual L-sigma relation with no zero-point shift. For a few galaxies without Balmer contamination, stellar rotation velocities are determined. One slow, one moderate, and one fast rotator are found. 54 references

  15. Progenitor's Signatures in Type Ia Supernova Remnants

    NARCIS (Netherlands)

    Chiotellis, A.; Kosenko, D.; Schure, K.M.; Vink, J.

    2013-01-01

    The remnants of Type Ia supernovae (SNe Ia) can provide important clues about their progenitor histories. We discuss two well-observed supernova remnants (SNRs) that are believed to have resulted from SNe Ia, and use various tools to shed light on the possible progenitor histories. We find that

  16. Optical Rain Gauge Instrument Handbook

    Energy Technology Data Exchange (ETDEWEB)

    Bartholomew, Mary Jane [Brookhaven National Lab. (BNL), Upton, NY (United States)

    2016-04-01

    To improve the quantitative description of precipitation processes in climate models, the U.S. Department of Energy (DOE)’s Atmospheric Radiation Measurement (ARM) Climate Research Facility deploys several types of rain gauges (MET, RAIN, and optical rain gauge [ORG] datastreams) as well as disdrometers (DISD and VDIS datastreams) at the Southern Great Plains (SGP) Site. This handbook deals specifically with the independent analog ORG (i.e., the ORG datastream).

  17. More rain compensation results

    Science.gov (United States)

    Sworder, D. D.; Vojak, R.

    1992-01-01

    To reduce the impact of rain-induced attenuation in the 20/30 GHz band, the attenuation at a specified signal frequency must be estimated and extrapolated forward in time on the basis of a noisy beacon measurement. Several studies have used model based procedures for solving this problem in statistical inference. Perhaps the most widely used model-based paradigm leads to the Kalman filter and its lineal variants. In this formulation, the dynamic features of the attenuation are represented by a state process (x(sub t)). The observation process (y(sub t)) is derived from beacon measurements. Some ideas relating to the signal processing problems related to uplink power control are presented. It is shown that some easily implemented algorithms hold promise for use in estimating rain induced fades. The algorithms were applied to actual data generated at the Virginia Polytechnic Institute and State University (VPI) test facility. Because only one such event was studied, it is not clear that the algorithms will have the same effectiveness when a wide range of events are studied.

  18. Music after the rain

    CERN Multimedia

    2006-01-01

    The group Home Cooking (left to right: Jean-Marie Planche, Tony Arnold, Serge Waeffler, Django Manglunki) entertains the crowd with a humoristic blues/rock performance. The earth moved in Prévessin on 29 July. This was not an earthquake but an 'international' music event, the seventeenth CERN Hardronic Festival, which saw musicians from many different countries, including Russia, Britain, Spain, France, Belgium and the USA, take to the stage. The audience rocked to music from eight different groups until the early hours. About a thousand people flocked to CERN to hear what the best of its musical talents had to offer. The evening was very nearly a wash-out, though. After a week of scorching hot temperatures, the heavens suddenly opened and the rain didn't stop until a few minutes before the first act came on stage. Thanks to this narrow escape, the organisers can boast a 17-year run of rain-free Hardronic festivals. All the different musical styles were given a warm reception, from traditional Russian folk...

  19. Diet of two sympatric felids (Leopardus tigrinus and Leopardus wiedii in a remnant of Atlantic forest, in the montane region of Espírito Santo, southeastern Brazil (English

    Directory of Open Access Journals (Sweden)

    Jardel Brandão Seibert

    2015-06-01

    Full Text Available We analyzed the diet of two sympatric felids, the oncilla and the margay, in the Brazilian Atlantic Forest. Fecal samples were collected from 2003 to 2005. Of the 52 fecal samples examined, 34 were confirmed to be from the oncilla and 18 of them from the margay. Small mammals (Rodentia and Didelphimorphia were the most important food item, followed by insects and birds. The food habit of the oncilla and the margay in the area were classified as a specialist carnivore, feeding in a variety of prey, which mammals were the most consumed item. The coexistence between those species may involve spatial and temporal segregation and the use of complementary items in the diet. (English

  20. Erosion by rain in the western Congo

    International Nuclear Information System (INIS)

    Ploey, J. de

    1967-01-01

    Vast expanses of the western part of central and southern Africa are covered with uniform, sandy formations of the Kalahari type. The topography of these areas and their present morphological characteristics are mainly the result of erosion by rain. Information on the hydrology of the surface waters in these areas is fairly limited and is insufficient to permit any conclusions regarding the way in which erosion by rain takes place. To obtain a better understanding of these phenomena, the author devised a series of experiments based on the use of 46 Sc-labelled radioactive sand. These experiments began at the beginning of the 1964/65 rainy season and are continuing. The experimental plot corresponds to convex and rectilinear portions of a hillside with a slope varying between 0 and 12 degrees. The vegetation consists of grassy savannah of substeppe appearance and secondary forests. Series of labelled samples were placed successively on the surface of the experimental plot and the erosive effect of rain was determined by measuring the residual concentrations after rainfall. Some samples were placed below a shield so as to eliminate the effects of splash and reveal the part played by runoff. Radiographic films were used to study the dispersion of labelled particles in the surrounding area. This radiographic method made it possible to determine the scale of erosion by splash for different rainfall conditions. The erosion diagrams obtained from these experiments show the correlations that exist between the intensity and duration of the rainfall and the erosion of the soil. Examination of the erosion diagrams and the shielded samples and analysis of the radiographs showed that erosion by rain on Kalahari ground covered with substeppe savannah is caused mainly by splash erosion and by dispersed, intermittent runoff. Sheet wash plays no part if the slope is less than 12 degrees. (author) [fr

  1. Hydrodynamic evolution of neutron star merger remnants

    Science.gov (United States)

    Liu, Men-Quan; Zhang, Jie

    2017-11-01

    Based on the special relativistic hydrodynamic equations and updated cooling function, we investigate the long-term evolution of neutron stars merger (NSM) remnants by a one-dimensional hydrodynamic code. Three NSM models from one soft equation of state, SFHo, and two stiff equations of state, DD2 and TM1, are used to compare their influences on the hydrodynamic evolution of remnants. We present the luminosity, mass and radius of remnants, as well as the velocity, temperature and density of shocks. For a typical interstellar medium (ISM) density with solar metallicity, we find that the NSM remnant from the SFHo model makes much more changes to ISM in terms of velocity, density and temperature distributions, compared with the case of DD2 and TM1 models. The maximal luminosity of the NSM remnant from the SFHo model is 3.4 × 1038 erg s-1, which is several times larger than that from DD2 and TM1 models. The NSM remnant from the SFHo model can maintain high luminosity (>1038 erg s-1) for 2.29 × 104 yr. Furthermore, the density and temperature of remnants at the maximal luminosity are not sensitive to the power of the original remnant. For the ISM with the solar metallicity and nH = 1 cm- 3, the density of the first shock ∼10-23 g cm-3 and the temperature ∼3 × 105 K in the maximal luminosity phase; The temperature of the first shock decreases and there is a thin 'dense' shell with density ∼10-21 g cm-3 after the maximal luminosity. These characteristics may be helpful for future observations of NSM remnants.

  2. Density and energy of supernova remnants

    Energy Technology Data Exchange (ETDEWEB)

    Canto, J [Manchester Univ. (UK). Dept. of Astronomy

    1977-12-01

    The effects of an interstellar magnetic field on the gas flow behind a strong shock front are considered. The ambient density and energy of supernova remnants are estimated from the intensity ratio of sulphur lines I(6717)/I(6731). It is found that, on average, the ambient density around galactic supernova remnants is 4 cm/sup -3/. The total energy appears to be the same for all supernova remnants (to within a factor = approximately 5). A mean value of 4 10/sup 51/ erg is found.

  3. Remnants of strong tidal interactions

    International Nuclear Information System (INIS)

    Mcglynn, T.A.

    1990-01-01

    This paper examines the properties of stellar systems that have recently undergone a strong tidal shock, i.e., a shock which removes a significant fraction of the particles in the system, and where the shocked system has a much smaller mass than the producer of the tidal field. N-body calculations of King models shocked in a variety of ways are performed, and the consequences of the shocks are investigated. The results confirm the prediction of Jaffe for shocked systems. Several models are also run where the tidal forces on the system are constant, simulating a circular orbit around a primary, and the development of tidal radii under these static conditions appears to be a mild process which does not dramatically affect material that is not stripped. The tidal radii are about twice as large as classical formulas would predict. Remnant density profiles are compared with a sample of elliptical galaxies, and the implications of the results for the development of stellar populations and galaxies are considered. 38 refs

  4. Methane rain on Titan

    Science.gov (United States)

    Toon, Owen B.; Mckay, Christopher P.; Courtin, Regis; Ackerman, Thomas P.

    1988-01-01

    The atmosphere of Titan is characterized by means of model computations based on Voyager IRIS IR spectra and published data from laboratory determinations of absorption coefficients and cloud refractive indices. The results are presented in tables and graphs, and it is pointed out that the presence of Ar is not required in the model. Particular attention is given to the role of CH4, which is found to form patchy clouds (with particle radii of 50 microns or greater and visible/IR optical depths of 2-5) at altitudes up to about 30 km. The mechanisms by which such rain-sized particles could form are discussed, and it is suggested that the observed 500-600/cm spectrum is affected much less by the CH4 clouds than by H2 or variations in the temperature of the high-altitude haze.

  5. Acid Rain: An Educational Opportunity?

    Science.gov (United States)

    Marion, James I.

    1984-01-01

    Deals with how educators can handle the subject of acid rain; illustrates suggestions with experiences of grade nine students visiting Frost Valley Environmental Education Center (Oliverea, New York) to learn scientific concepts through observation of outdoor phenomena, including a stream; and discusses acid rain, pH levels, and pollution control…

  6. Rain Gardens: Stormwater Infiltrating Systems

    Science.gov (United States)

    The hydrological dynamics and changes in stormwater nutrient concentrations within rain gardens were studied by introducing captured stormwater runoff to rain gardens at EPA’s Urban Water Research Facility in Edison, New Jersey. The runoff used in these experiments was collected...

  7. Evaluation of the RAIN project

    International Nuclear Information System (INIS)

    Stuanes, A.; Dickson, W.; Jenkins, A.; Rasmussen, L.; Stordal, F.

    1991-11-01

    This report presents a scientific assessment of the RAIN project. It describes the main hypotheses tested and the applied methods. The major results of the research are highlighted and discussed, and they are placed in the perspective of national and international acid rain research. An important part of the RAIN project has been to provide information to the public about the acid rain problem, and in this way it has performed an important background role in influencing political decisions and legislation. The RAIN project is regarded as a cost effective research effort, and the novel approach and capital investment will enable further manipulation studies at these sites in the future. It is recommended that the project is continued in the immediate future, with some modification to answer specific questions resulting from the collected data. 24 refs., 6 figs., 1 tab

  8. A Model of the Vela Supernova Remnant

    Science.gov (United States)

    Gvaramadze, Vasilii

    2000-10-01

    A model of the Vela supernova remnant (SNR) based on a cavity explosion of a supernova (SN) star is proposed. It is suggested that the general structure of the remnant is determined by the interaction of the SN blast wave with a massive shell created by the SN progenitor (15-20 M_solar) star. A possible origin of the nebula of hard X-ray emission detected around the Vela pulsar is discussed.

  9. Evolution of supernova remnants. III. Thermal waves

    International Nuclear Information System (INIS)

    Chevalier, R.A.

    1975-01-01

    The effect of heat conduction on the evolution of supernova remnants is investigated. A thermal wave, or electron conduction front, can travel more rapidly than a shock wave during the first thousand years of the remnant's evolution. A self-similar solution describing this phase has been found by Barenblatt. Numerical computations verify the solution and give the evolution past the thermal wave phase. While shell formation is not impeded, the interior density and temperature profiles are smoothed by the action of conduction

  10. Supernova Remnant in 3-D

    Science.gov (United States)

    2009-01-01

    [figure removed for brevity, see original site] Click on the image for the movie For the first time, a multiwavelength three-dimensional reconstruction of a supernova remnant has been created. This stunning visualization of Cassiopeia A, or Cas A, the result of an explosion approximately 330 years ago, uses data from several telescopes: X-ray data from NASA's Chandra X-ray Observatory, infrared data from NASA's Spitzer Space Telescope and optical data from the National Optical Astronomy Observatory 4-meter telescope at Kitt Peak, Ariz., and the Michigan-Dartmouth-MIT 2.4-meter telescope, also at Kitt Peak. In this visualization, the green region is mostly iron observed in X-rays. The yellow region is a combination of argon and silicon seen in X-rays, optical, and infrared including jets of silicon plus outer debris seen in the optical. The red region is cold debris seen in the infrared. Finally, the blue reveals the outer blast wave, most prominently detected in X-rays. Most of the material shown in this visualization is debris from the explosion that has been heated by a shock moving inwards. The red material interior to the yellow/orange ring has not yet encountered the inward moving shock and so has not yet been heated. These unshocked debris were known to exist because they absorb background radio light, but they were only recently discovered in infrared emission with Spitzer. The blue region is composed of gas surrounding the explosion that was heated when it was struck by the outgoing blast wave, as clearly seen in Chandra images. To create this visualization, scientists took advantage of both a previously known phenomenon the Doppler effect and a new technology that bridges astronomy and medicine. When elements created inside a supernova, such as iron, silicon and argon, are heated they emit light at certain wavelengths. Material moving towards the observer will have shorter wavelengths and material moving away will have longer wavelengths. Since the amount

  11. quantification of rain quantification of rain induced artifacts on digital

    African Journals Online (AJOL)

    eobe

    DSTV) ... satellite television, rain attenuation, digital artifacts, pixelation, rainfall rate. 1. ... screen and blocking are commonly observed in .... The precipitation data was collected using a self- ..... Networks: Comparison at Equatorial and Subtropical.

  12. Actual state of plant decline phenomena due to acid rain and others

    International Nuclear Information System (INIS)

    Yokobori, Makoto

    1992-01-01

    Recently, Japanese mass communication earnestly reports on the effect that acid rain exerts to natural environment. Also the researches have been carried out on the present state of rainwater acidification, the mechanism of the effect of acid rain to plants, the experiment using artificial acid rain, and the foreign theories on the cause of the decline of forests. But the example of the damage of trees and plants in fields, of which the true cause is understood to be acid rain, is not found. The author has engaged in the research on forest protection for long years, and according to his experience, in the present Japanese research on acid rain, there are a number of important pitfalls. Acid rain theory is only one of many hypotheses. It must be verified by the proper research, and this point is important. Ibaraki Prefectural Forest Experiment station has carried out the consultation on the diagnosis and restoration of tree conditions, and the decline of trees and its cause are reported according to the examples of investigation. In the consultation in the last nine years, the decline of trees caused by acid rain was not confirmed. (K.I.)

  13. Radioiodine Remnant Ablation: A Critical Review

    International Nuclear Information System (INIS)

    Bal, Chandra Sekhar; Padhy, Ajit Kumar

    2015-01-01

    Radioiodine remnant ablation (RRA) is considered a safe and effective method for eliminating residual thyroid tissue, as well as microscopic disease if at all present in thyroid bed following thyroidectomy. The rationale of RRA is that in the absence of thyroid tissue, serum thyroglobulin (Tg) measurement can be used as an excellent tumor marker. Other considerations are like the presence of significant remnant thyroid tissue makes detection and treatment of nodal or distant metastases difficult. Rarely, microscopic disease in the thyroid bed if not ablated, in the future, could be a source of anaplastic transformation. On the other hand, microscopic tumor emboli in distant sites could be the cause of distant metastasis too. The ablation of remnant tissue would in all probability eliminate these theoretical risks. It may be noted that all these are unproven contentious issues except postablation serum Tg estimation that could be a good tumor marker for detecting early biochemical recurrence in long-term follow-up strategy. Radioactive iodine is administered as a form of “adjuvant therapy” for remnant ablation. There have been several reports with regard to the administered dose for remnant ablation. The first report of a prospective randomized clinical trial was published from India by a prospective randomized study conducted at the All India Institute of Medical Sciences, New Delhi in the year 1996. The study reported that increasing the empirical 131 I initial dose to more than 50 mCi results in plateauing of the dose-response curve and thus, conventional high-dose remnant ablation needs critical evaluation. Recently, two important studies were published: One from French group and the other from UK on a similar line. Interestingly, all three studies conducted in three different geographical regions of the world showed exactly similar conclusion. The new era of low-dose remnant ablation has taken a firm scientific footing across the continents

  14. Effects of using kaolin waste and granite waste as raw materials for the production of low-water absorption ceramic tiles; Efeitos da co-utilizacao dos residuos do beneficiamento do caulim e da extracao do granito rain forest para a producao de revestimentos ceramicos com baixa absorcao de agua

    Energy Technology Data Exchange (ETDEWEB)

    Freires, H.P.; Argonz, R.; Nogueira, R.E.F.Q.; Sasaki, J.M., E-mail: argonz@ufc.br [Universidade Federal do Ceara (UFC), Fortaleza, CE (Brazil); Sales, J.C. [Universidade do Vale do Aracau (UVA), Crateus, CE (Brazil)

    2012-07-01

    This study aims to evaluate the potential of co-use of granite waste (Rain Forest) and kaolin waste as raw material for the manufacture of ceramic coating of low water absorption. Raw materials were characterized by X-ray diffraction. Kaolin residue was added to the residue of granite in the following proportions (in wt%): 0, 10, 20, 30, 40 and 50%. Specimens were fabricated by uniaxial pressing and fired at 1175,1200 and 1225 deg C. Studies of firing linear shrinkage, water absorption, apparent porosity, apparent density and tensile bending test (or rupture modulus) were conducted. The temperature of 1225 deg C allowed the use of a mixture of 50% granite residue and 50% kaolin residue. Ceramic parts made from that mixture exhibited the maximum values required by the Brazilian Standard NBR 13818 for water absorption, shrinkage and density. (author)

  15. Abundância e frugivoria da quiropterofauna (Mammalia, chiroptera de um fragmento no noroeste do Estado do Paraná, Brasil - doi: 10.4025/actascibiolsci.v32i3.5351 Chiropterofauna abundance and frugivory in a forest remnant in northwestern Paraná State, Brazil - doi: 10.4025/actascibiolsci.v32i3.5351

    Directory of Open Access Journals (Sweden)

    Janaina Gazarini

    2010-09-01

    Full Text Available A abundância e a frugivoria de morcegos que compõem a taxocenose em uma área de mata ripária, à margem esquerda do rio Ivaí, foram foco do presente estudo. O Recanto Marista possui 57,6 hectares, dos quais 40,8 são cobertos por Floresta Estacional Semidecidual, situado no município de Doutor Camargo, região Noroeste do Estado do Paraná. Foram realizadas 14 noites de capturas de morcegos de maio de 2007 a janeiro de 2008, com redes-neblina (7 x 2,5 m, totalizando 13.475 m² h de esforço amostral, distribuído em 72h de esforço. Foram capturados 193 indivíduos, representantes de dez espécies, pertencentes a duas famílias: Phyllostomidae (Artibeus lituratus, Sturnira lilium, Carollia perspicillata, Artibeus cf. fimbriatus, Artibeus planirotris, Desmodus rotundus e Pygoderma bilabiatum e Vespertilionidae (Myotis nigricans, Eptesicus sp. e Lasiurus blossevillii. Um representante da família Molossidae (Molossus rufus foi encontrado morto no solo. Foram consumidos frutos pertencentes às famílias Moraceae (Ficus guaranitica, Ficus insipida, Ficus sp. e Maclura tinctoria, Solanaceae (Solanum aspero-lanatum e Solanum sp. , Piperaceae (Piper aduncum, Piper amalago e Piper sp. e Urticaceae (Cecropia pachystachya e Cecropia sp..This study aims to evaluate the abundance and frugivory of bats from the Recanto Marista, a small riparian forest remnant in the margins of the Ivaí river. The Recanto Marista has 57.6 ha, of which 40.8 ha are covered by semideciduous seasonal forest and is located in the Doutor Camargo municipality. Collections were conducted from May 2007 to January 2008 using mist nets (7 x 2.5 m totaling 13,475 m² h and comprising about 72 hours. Ten species were found pertaining to two families, Phyllostomidae (Artibeus lituratus, Sturnira lilium, Carollia perspicillata, Artibeus cf. fimbriatus, Artibeus planirotris, Desmodus rotundus and Pygoderma bilabiatum and Vespertilionidae (Myotis nigricans, Eptesicus sp. and Lasiurus

  16. Considerações sobre Coprophanaeus ensifer (Germar (Coleoptera, Scarabaeidae em um remanescente de Mata Atlântica no Estado da Paraíba, Brasil Notes about Coprophanaeus ensifer (Germar (Coleoptera, Scarabaeidae in a remnant of the Atlantic Forest in the State of Paraíba, Brazil

    Directory of Open Access Journals (Sweden)

    Ana Aline Endres

    2005-09-01

    Full Text Available Os insetos da família Scarabaeidae se alimentam da matéria orgânica em decomposição, participando ativamente da ciclagem de nutrientes. C. ensifer é um necrófago de grande porte que ocorre em áreas de florestas tropicais. Este estudo teve por objetivo conhecer o padrão sazonal da espécie neste ambiente e avaliar a atratividade das iscas utilizadas. Foram realizadas 13 coletas entre os meses de Dezembro/98 e Dezembro/99 na Mata do Buraquinho, um remanescente de Mata Atlântica em João Pessoa, PB. Foram coletados 71 espécimes usando armadilhas com quatro tipos de isca: 35 em carne de porco, 22 em rim bovino e 14 indivíduos em carne bovina, não havendo diferenças significativas entre as iscas em relação a sua atratividade para com os insetos. Não foi coletado nenhum espécime em fígado bovino. A abundância mensal esteve diretamente correlacionada com a precipitação (r s=0,65; pInsects of the family Scarabaeidae feed on organic matter in decomposition, participating actively in biogeocycling of nutrients. C. ensifer is a large-sized necrophagous beette that occurs in tropical forests. In the present work we aimed to record some ecological characteristics of this species regarding the seasonality and bait attractivity. Thirteen samples were performed between December/1998 and December/1999 in the Mata do Buraquinho, a remnant of the Atlantic Forest in João Pessoa, PB. Seventy-one specimens were captured in four baited pitfall traps: 35 on pork meat, 22 on kidney, and 14 on bovine meat. There was no significant difference among the baits with respect to their stimuli for attracting the insects. No specimens of C. ensifer were trapped on baits of liver. The monthly abundance of insects is positively correlated the precipitation (r s=0,65; p<0,05 and humidity (r s=0,55; p<0,05 and inversely with temperature (r s=-0,70; p<0,01. The specimens were collected only from April to September, within the rainy period, an aspect that

  17. Modelling the interaction of thermonuclear supernova remnants with circumstellar structures: the case of Tycho's supernova remnant

    NARCIS (Netherlands)

    Chiotellis, A.; Kosenko, D.; Schure, K.M.; Vink, J.; Kaastra, J.S.

    2013-01-01

    The well-established Type Ia remnant of Tycho's supernova (SN 1572) reveals discrepant ambient medium-density estimates based on either the measured dynamics or the X-ray emission properties. This discrepancy can potentially be solved by assuming that the supernova remnant (SNR) shock initially

  18. [Relationship between simulated acid rain stress and leaf reflectance].

    Science.gov (United States)

    Song, Xiao-dong; Jiang, Hong; Yu, Shu-quan; Zhou, Guo-mo; Jiang, Zi-shan

    2010-01-01

    Acid rain is a worldwide environmental problem. Serious acid rain pollution in subtropical China has constituted a potential threat to the health of the local forest. In the present paper, the changing properties of the chlorophyll concentration and spectral reflectance at the visible wavelengths for the six subtropical broad-leaved tree species leaves under simulated acid rain (SAR) treatment with different pH levels were studied. With the increasing strength of the SAR, the chlorophyll concentrations of the experimental species under pH 2.5 and pH 4.0 treatment were higher than that under pH 5.6; the spectral reflectance at the visible wavelengths for pH 2.5 and pH 4.0 were lower than that for pH 5.6 in general; while there weren't significant differences between pH 2.5 and pH 4.0. After the treatment with different levels of SAR, the differences in spectral reflectance at the visible wavelengths mainly focused around the green peak and red edge on the reflectance curve. The subtropical broad-leaved tree species studied were relatively not sensitive to acid rain stresses; some stronger acid rain may accelerate the growth of the tree species used here to some extent.

  19. The role of remnant trees in carbon sequestration, vegetation structure and tree diversity of early succession regrowing fallows in eastern Sierra Leone

    DEFF Research Database (Denmark)

    Cuni Sanchez, Aida; Lindsell, Jeremy A.

    2017-01-01

    Remnant tree presence affects forest recovery after slash-and-burn agriculture. However, little is known about its effect on above-ground carbon stocks, especially in Africa. We focused our study on Sierra Leone, part of the Upper Guinean forests, an important centre of endemism threatened...

  20. analysis of rain analysis of rain rate and rain attenuation for earth

    African Journals Online (AJOL)

    eobe

    rate measurements were carried out using the Moupfouma and Chebil models ate measurements were ... The rain in Nigeria is characterized by high intensity rainfall, high frequency of ..... Journal of Atmospheric and Solar-. Terrestrial Physics ...

  1. Autopsy of the Supernova Remnant Cassiopeia A

    Science.gov (United States)

    Milisavljevic, Dan; Fesen, Robert A.

    2014-01-01

    Three-dimensional kinematic reconstructions of optically emitting ejecta in the young Galactic supernova remnant Cassiopeia A (Cas A) are discussed. The reconstructions encompass the remnant's faint outlying ejecta knots, including the exceptionally high-velocity NE and SW streams of debris often referred to as `jets'. The bulk of Cas A's ejecta are arranged in several circular rings with diameters between approximately 30'' (0.5 pc) and 2' (2 pc). We suggest that similar large-scale ejecta rings may be a common phenomenon of young core-collapse remnants and may explain lumpy emission line profile substructure sometimes observed in spectra of extragalactic core-collapse supernovae years after explosion. A likely origin for these large ejecta rings is post-explosion input of energy from plumes of radioactive 56Ni-rich ejecta that rise, expand, and compress non-radioactive material to form bubble-like structures.

  2. Cosmic Ray Acceleration in Supernova Remnants

    International Nuclear Information System (INIS)

    O'C Drury, Luke

    2005-01-01

    This paper describes some recent developments in our understanding of cosmic ray acceleration in supernova remnant shocks. It is pointed out that while good agreement now exists as to steady nonlinear modifications to the shock structure, there is also growing evidence that the mesoscopic scales may not in fact be steady and that significant instabilities associated with magnetic field amplification may be a feature of strong collisionless plasma shocks. There is strong observational evidence for such magnetic field amplification, and it appears to solve a number of long-standing issues concerned with acceleration of cosmic rays in supernova remnants

  3. X-ray haloes around supernova remnants

    International Nuclear Information System (INIS)

    Morfill, G.E.; Aschenbach, B.

    1984-01-01

    Recent observations of the Cas-A supernova remnant have shown X-ray emissions not only from the interior, but also from a fainter 'halo' extending beyond what is normally regarded as the outer boundary, or shock front. The authors suggest that this may be due to the diffusion of energetic, charged particles out of the remnant giving rise to precursor structure of the type predicted by the theory of diffusive shock acceleration. If this is the case we are seeing thermal emission from ambient gas heated by compression and wave dissipation. (author)

  4. X-ray haloes around supernova remnants

    Energy Technology Data Exchange (ETDEWEB)

    Morfill, G.E.; Aschenbach, B. (Max-Planck-Institut fuer Physik und Astrophysik, Garching (Germany, F.R.). Inst. fuer Extraterrestrische Physik); Drury, L.O' C. (Max-Planck-Institut fuer Kernphysik, Heidelberg (Germany, F.R.))

    1984-09-27

    Recent observations of the Cas-A supernova remnant have shown X-ray emissions not only from the interior, but also from a fainter 'halo' extending beyond what is normally regarded as the outer boundary, or shock front. The authors suggest that this may be due to the diffusion of energetic charged particles out of the remnant giving rise to precursor structure of the type predicted by the theory of diffusive shock acceleration. If this is the case we are seeing thermal emission from ambient gas heated by compression and wave dissipation.

  5. Canopy seed banks as time capsules of biodiversity in pasture-remnant tree crowns.

    Science.gov (United States)

    Nadkarni, Nalini M; Haber, Willam A

    2009-10-01

    Tropical pastures present multiple barriers to tree regeneration and restoration. Relict trees serve as "regeneration foci" because they ameliorate the soil microclimate and serve as safe spots for dispersers. Here, we describe another mechanism by which remnant trees may facilitate pasture regeneration: the presence of seed banks in the canopy soil that accumulates from decomposing epiphytes within the crowns of mature remnant trees in tropical cloud forest pastures. We compared seed banks of canopy soils (histosols derived from fallen leaves, fruits, flower, and twigs of host trees and epiphytes, dead bryophytes, bark, detritus, dead animals, and microorganisms, and dust that accumulate on trunks and the upper surfaces of large branches) in pastures, canopy soils in primary forest trees, and soil on the forest floor in Monteverde, Costa Rica. There were 5211 epiphytic and terrestrial plant seeds in the three habitats. All habitats were dominated by seeds in a relatively small number of plant families, most of which were primarily woody, animal pollinated, and animal dispersed. The density of seeds on the forest floor was greater than seed density in either pasture-canopy or forest-canopy soils; the latter two did not differ. Eight species in 44 families and 61 genera from all of the habitats were tallied. There were 37 species in the pasture-canopy soil, 33 in the forest-canopy soil, and 57 on the forest floor. Eleven species were common to all habitats. The mean species richness in the pasture canopy was significantly higher than the forest canopy (F =83.38; p banks of pasture trees can function as time capsules by providing propagules that are removed in both space and time from the primary forest. Their presence may enhance the ability of pastures to regenerate more quickly, reinforcing the importance of trees in agricultural settings.

  6. Effects of acid rain

    Energy Technology Data Exchange (ETDEWEB)

    1976-03-01

    The ecological problems that are caused by sulfur pollution in Scandinavia are addressed. Subsequent chemical and physical transformations that the pollutants undergo in the atmosphere are included. The effects of pollutants on soil nutrients, with consequences mainly for forest production, are discussed. Other effects include acidification of lakes and rivers, resulting in decreased fish production. The size of the drop in pH is quite substantial in some of the lakes. The decreased pH has an immediate effect on the change in species composition of fish populations, such as trout and salmon. Efforts to reduce sulfur pollution are discussed. A long term program for the reduction of sulfur in fuel oil has been introduced. At present, there is a ban on the use of oil containing more then 2.5% S (by weight). A further ban on oil containing more than 1% sulfur is in effect in the three major urban areas of Sweden as well as a number of counties. It has been urged by environmental health authorities that in urban pollution control sulfur should be regarded as an indicator of pollutions and not be dealt with as an isolated problem.

  7. Spatial and Temporal Relationships of Old-Growth and Secondary Forests in Indiana, USA

    Science.gov (United States)

    Martin A. Spetich; George R. Parker; Eric J. Gustafson

    1997-01-01

    We examined the spatial pattern of forests in Indiana to: (1) determine the extent, connectivity and percent edge of all forests, (2) examine the change in connectivity among these forests if all riparian zones were replanted to forest or other native vegetation, (3) determine the location, spatial dispersion and percent edge of current old-growth forest remnants, (4)...

  8. Maturação e morfometria dos frutos de miconia Albicans (Swartz triana (melastomataceae em um remanescente de floresta estacional semidecídua montana em Lavras, MG Maturation and morphometrics of the fruits of Miconia albicans (Swartz triana (melastomataceae in a remnant of montane seasonal semideciduous forest in Lavras, MG

    Directory of Open Access Journals (Sweden)

    Fábio de Almeida Vieira

    2009-12-01

    Full Text Available Os objetivos deste trabalho foram analisar a dinâmica da maturação dos frutos e avaliar quantitativamente algumas características físicas dos frutos de Miconia albicans (Swartz Triana em um remanescente de Floresta Estacional Semidecídua Montana. A atividade, intensidade e sincronia de 20 indivíduos foram analisadas em relação aos eventos de frutificação, correlacionando-os com as variáveis climáticas. Analisou-se a morfometria (comprimento, largura e massa de 130 frutos de 10 indivíduos. A intensidade da fenofase de frutos maduros nas plantas correlacionou-se significativamente com a precipitação média do período (rS = 0,611; P The aim of this study was to examine the dynamics of fruit maturation and quantitatively assess some physical characteristics of the fruits of Miconia albicans (Swartz Triana in a remnant of Montane Seasonal Semideciduous Forest. The activity and synchrony of 20 individuals were analyzed in regard to the proportion of fruiting events, and to help to determine their correlation to abiotic factors. Morphometric traits (fruit length, diameter and mass of 130 fruits from ten individuals were analyzed. The number of fruits maturing showed a significant correlation with the mean precipitation (rS = 0.611; P < 0.05. M. albicans presented a high number of small seeds per fruit ( = 28.05 ± 1.45 s.d.. The fresh mass of the fruit was approximately equal to the pulp mass (rS = 0.988; P < 0.05. Thepulp contributed with 94% of the total mass, demonstrating the potential importance of this species for frugivores. The results indicate the period of high intrapopulation synchrony of the studied phenophases, which can be a useful guide in the collection of seeds for germoplasm banks and recovery of degraded areas.

  9. Wind dispersal of alien plant species into remnant natural vegetation from adjacent agricultural fields

    Directory of Open Access Journals (Sweden)

    Chika Egawa

    2017-07-01

    Full Text Available Knowledge regarding the seed dispersal of alien species is crucial to manage invasion risk in fragmented natural habitats. Focusing on wind dispersal, this study assessed the spatial and quantitative extents to which a remnant natural fen receives the seeds of alien species dispersed from adjacent hay meadows in Hokkaido, northern Japan. I established a total of 80 funnel seed traps in the fen at distances of 1, 2, 5, 10, 20, 30, 50, and 100 m from the meadows. The proportion of alien species in the seed rain at each distance was quantified, and the 99th-percentile dispersal distance from the meadows was estimated for each alien species by constructing dispersal kernels. Despite the presence of a marginal ditch and an elevational difference between the fen and the meadows, five alien species, including four grasses that do not have modified seed structures for wind dispersal, dispersed their seeds into the fen. These alien species accounted for up to 65.9% of the seed rain in terms of quantity. The 99th-percentile dispersal distances of the alien species ranged from 3.8 m to 309.3 m, and these distances were longer than the values predicted on the basis of their functional traits, such as terminal velocity. The results of this study demonstrated that numerous seeds of farmland-derived alien species were transported into the remnant vegetation via wind dispersal, and that simple predictions of dispersal distance based on functional traits could underestimate the potential area that alien species can reach. Continuous management both in farmland (to reduce seed escape and in remnant vegetation (to prevent the establishment of alien species is necessary to protect native vegetation from biological invasion in agricultural landscapes.

  10. Acid rain. Les pluies acides

    Energy Technology Data Exchange (ETDEWEB)

    Curren, T

    1979-11-28

    This report was produced for the use of Members of Parliament and House of Commons committees. The document describes the formation of acid rain, emissions of acidifying pollutants in North America, the growth of the problem and its environmental effects on aquatic and terrestrial ecosystems, human health and man-made structures. Areas of Canada which are most susceptible are identified. Actions taken by Parliament are given, including the formation of a sub-committee on acid rain and the passing of Bill C-51 in 1980 to amend the Clean Air Act, bringing it closer to a similar law in the U.S. A chronology of government responses to acid rain at the international, national and provincial level, is given. The most recent government actions included the passing of the US Clean Air Act by the Senate, the amending of the act into law, and commencement of negotiations to develop a Canada-US Air Quality Accord. 10 refs.

  11. Particle acceleration and nonthermal radiation in supernova remnants

    International Nuclear Information System (INIS)

    Zirakashvili, Vladimir

    2013-01-01

    Cosmic ray acceleration and magnetic amplification in shell-type supernova remnants is shortly reviewed. The results on the modeling of broadband electromagnetic emission from supernova remnants are presented and compared with observations.

  12. GALACTIC AND EXTRAGALACTIC SUPERNOVA REMNANTS AS SITES OF PARTICLE ACCELERATION

    Directory of Open Access Journals (Sweden)

    Manami Sasaki

    2013-12-01

    Full Text Available Supernova remnants, owing to their strong shock waves, are likely sources of Galactic cosmic rays. Studies of supernova remnants in X-rays and gamma rays provide us with new insights into the acceleration of particles to high energies. This paper reviews the basic physics of supernova remnant shocks and associated particle acceleration and radiation processes. In addition, the study of supernova remnant populations in nearby galaxies and the implications for Galactic cosmic ray distribution are discussed.

  13. Variations in dung beetles assemblages (Coleoptera: Scarabaeidae within two rain forest habitats in French Guiana Variaciones de las agregaciones de escarabajos coprófagos (Coleoptera: Scarabaeidae en dos hábitats del bosque tropical en la Guayana Francesa

    Directory of Open Access Journals (Sweden)

    François Feer

    2013-06-01

    Full Text Available The structure of dung beetle communities inhabiting tropical forests are known to be sensitive to many kinds of environmental changes such as microclimate related to vegetation structure. I examined Scarabaeinae assemblages in two sites of undisturbed high forest and two sites of low forest forming a transitional zone with the open habitat of an inselberg in French Guiana. Sampling was made with pitfall and flight interception traps during 2003 and 2004. The driest and warmest conditions characterized the low forest sites. Across two years we obtained 2 927 individuals from 61 species with pitfall traps and 1 431 individuals from 85 species with flight interception traps. Greater species richness and abundance characterized all sites sampled with pitfall traps during 2003 more than 2004. In 2003 no differences were detected among sites by rarefaction analyses. In 2004 the species richest high forest site was significantly different from one of the low forest sites. For both years Clench model asymptotes for species richness were greater in high forest than in low forest sites. For both years, mean per-trap species richness, abundance and biomass among high forest sites were similar and higher than in low forest sites, especially where the lowest humidity and the highest temperature were recorded. Within the two low forest sites, species richness and abundance recorded during the second year, decreased with distance to edge. Different dominant roller species characterized the pitfall samples in one site of low forest and in other sites. Small variations in microclimatic conditions correlated to canopy height and openness likely affected dung beetle assemblages but soil depth and the presence of large mammals providing dung resource may also play a significant role.Es conocido que la estructura de las comunidades de escarabajos coprófagos que habitan los bosques tropicales es sensible a diferentes tipos de cambios ambientales tales como el

  14. Organic aerosols from biomass burning in Amazonian rain forest and their impact onto the environment; La combustione di biomassa nella Foresta Amazzonica Aerosoli organici e impatto sull'ambiente

    Energy Technology Data Exchange (ETDEWEB)

    Cecinato, A; Mabilia, R [Consiglio Nazionale delle Ricerche, Istituto sull' Inquinamento Atmosferico, Monterotondo Scalo, RM (Italy); De Castro Vasconcellos, P [Sao Paulo Universidad, Sao Paulo (Brazil). Instituto de Pesquisas Energeticas e Nucleares, Dept. de Engenharia Quimica Ambiental

    2001-03-01

    A field campaign performed in Southern Brazilian Amazonia in 1993 has proved that this region is subjected to fallout of particulated exhausts released by fires of forestal biomass. In fact, organic content of aerosols collected at urban sites located on the border of pluvial forest, about 50 km from fires, was similar to that of biomass burning exhausts. Aerosol composition is indicative of dolous origin of fires. However, organic contents seems to be influenced by two additional sources, i. e. motor vehicle and high vegetation emission. Chemical pattern of organic aerosols released by biomass burning of forest seems to promote occurrence of photochemical smog episodes in that region. [Italian] Una campagna di misura realizzata nella regione amazzonica nel 1993 ha dimostrato la ricaduta sull'area circostante dei prodotti di combustione della biomassa forestale, attraverso la speciazione degli aerosoli atmosferici raccolti in un sito urbano posto ai margini della foresta, tuttavia le poveri sospese rivelano l'origine dolosa degli incendi. La composizione chimica degli aerosoli organici provenienti dalla combustione di biomassa sembra favorire i processi di smog fotochimico nella regione.

  15. Forest biological diversity interactions with resource utilization

    Science.gov (United States)

    S.T. Mok

    1992-01-01

    The most important forest resources of the Asia-Pacific region are the highly diverse rain forests. Utilization of the resource is a natural and inevitable consequence of the region's socio-economic development. The sustainable management and development of forest resources in the region can be achieved by implementing conservational forestry, which is based on...

  16. The Rain-Powered Cart

    Science.gov (United States)

    2016-08-05

    University of America Press, Washington, DC 20064, USA E-mail: mungan@usna.edu and lipscombe@cua.edu Received 10 May 2016, revised 22 June 2016 Accepted for...renewable energy (Some figures may appear in colour only in the online journal) A familiar problem treats how wet a person walking in rain becomes as they

  17. Neutron Star/supernova Remnant Associations

    Science.gov (United States)

    Gvaramadze, V. V.

    We propose a new approach for studying the neutron star/supernova remnant associations, based on the idea that the (diffuse) supernova remnants (SNRs) can be products of an off-centred supernova (SN) explosion in a preexisting bubble created by the wind of a moving massive star. A cavity SN explosion of a moving star results in a considerable offset of the neutron star (NS) birth-place from the geometrical centre of the SNR. Therefore: a) the high transverse velocities inferred for a number of NSs (e.g. PSR B 1610-50, PSR B 1757-24, SGR 0525-66) through their association with SNRs can be reduced; b) the proper motion vector of a NS should not necessarily point away from the geometrical centre of the associated SNR. Taking into account of these two facts allow us to enlarge the circle of possible NS/SNR associations, and could significantly affect the results of previous studies of NS/SNR associations. The possibilities of our approach are illustrated with the example of the association between PSR B 1706-44 and SNR G 343.1-2.3. We show that this association could be real if both objects are the remnants of a SN exploded within a mushroom-like cavity (created by the SN progenitor wind breaking out of the parent molecular cloud and expanding into an intercloud medium of a much less density). We also show that the SN explosion sites in some middle-aged (shell-like) SNRs could be marked by (compact) nebulae of thermal X-ray emission. The possible detection of such nebulae within middle-aged SNRs could be used for the re-estimation of implied transverse velocities of known NSs or for the search of new stellar remnants possibly associated with these SNRs.

  18. Supernova remnants in the GC region

    Science.gov (United States)

    Asvarov, Abdul

    2016-07-01

    Along with the central Black hole the processes of active star formation play very important role in the energetics of the Galactic center region. The SNe and their remnants (SNRs) are the main ingredients of the processes of star formation. SNRs are also the sources of electromagnetic radiation of all wavelengths from the optical to hard gamma rays. In the presented work we consider the physics of supernova remnants evolving in extreme environmental conditions which are typical for the region of the Galactic center. Because of the high density and strong inhomogeneity of the surrounding medium these objects remain practically invisible at almost all wavelengths. We model evolution of SNR taking into account the pressure of the surrounding medium and the gravitational field of the matter (stars, compact clouds, dark matter) inside the remnant. As it is well established, considerable portion of the kinetic energy of the SNR can be converted into the cosmic ray particles by diffusive shock acceleration mechanism. Therefore the effect of particle acceleration is also included in the model (with the effectiveness of acceleration as a free parameter). Using the observed radiation fluxes at different wavelengths we attempt to obtain limits on the parameters of the model of the Galactic Center, namely, the frequency of star birth, the average density of the matter and radiation field, etc.

  19. THE FIRST FERMI LAT SUPERNOVA REMNANT CATALOG

    Energy Technology Data Exchange (ETDEWEB)

    Acero, F.; Ballet, J. [Laboratoire AIM, CEA-IRFU/CNRS/Université Paris Diderot, Service d’Astrophysique, CEA Saclay, F-91191 Gif sur Yvette (France); Ackermann, M.; Buehler, R. [Deutsches Elektronen Synchrotron DESY, D-15738 Zeuthen (Germany); Ajello, M. [Department of Physics and Astronomy, Clemson University, Kinard Lab of Physics, Clemson, SC 29634-0978 (United States); Baldini, L. [Università di Pisa and Istituto Nazionale di Fisica Nucleare, Sezione di Pisa I-56127 Pisa (Italy); Barbiellini, G. [Istituto Nazionale di Fisica Nucleare, Sezione di Trieste, I-34127 Trieste (Italy); Bastieri, D.; Buson, S. [Istituto Nazionale di Fisica Nucleare, Sezione di Padova, I-35131 Padova (Italy); Bellazzini, R. [Istituto Nazionale di Fisica Nucleare, Sezione di Pisa, I-56127 Pisa (Italy); Bissaldi, E. [Istituto Nazionale di Fisica Nucleare, Sezione di Bari, I-70126 Bari (Italy); Blandford, R. D.; Bloom, E. D.; Bottacini, E.; Caliandro, G. A.; Cameron, R. A. [W. W. Hansen Experimental Physics Laboratory, Kavli Institute for Particle Astrophysics and Cosmology, Department of Physics and SLAC National Accelerator Laboratory, Stanford University, Stanford, CA 94305 (United States); Bonino, R. [Istituto Nazionale di Fisica Nucleare, Sezione di Torino, I-10125 Torino (Italy); Brandt, T. J. [NASA Goddard Space Flight Center, Greenbelt, MD 20771 (United States); Bregeon, J. [Laboratoire Univers et Particules de Montpellier, Université Montpellier, CNRS/IN2P3, Montpellier (France); Bruel, P., E-mail: francesco.depalma@ba.infn.it, E-mail: t.j.brandt@nasa.gov, E-mail: john.w.hewitt@unf.edu [Laboratoire Leprince-Ringuet, École polytechnique, CNRS/IN2P3, Palaiseau (France); and others

    2016-05-01

    To uniformly determine the properties of supernova remnants (SNRs) at high energies, we have developed the first systematic survey at energies from 1 to 100 GeV using data from the Fermi Large Area Telescope (LAT). Based on the spatial overlap of sources detected at GeV energies with SNRs known from radio surveys, we classify 30 sources as likely GeV SNRs. We also report 14 marginal associations and 245 flux upper limits. A mock catalog in which the positions of known remnants are scrambled in Galactic longitude allows us to determine an upper limit of 22% on the number of GeV candidates falsely identified as SNRs. We have also developed a method to estimate spectral and spatial systematic errors arising from the diffuse interstellar emission model, a key component of all Galactic Fermi LAT analyses. By studying remnants uniformly in aggregate, we measure the GeV properties common to these objects and provide a crucial context for the detailed modeling of individual SNRs. Combining our GeV results with multiwavelength (MW) data, including radio, X-ray, and TeV, we demonstrate the need for improvements to previously sufficient, simple models describing the GeV and radio emission from these objects. We model the GeV and MW emission from SNRs in aggregate to constrain their maximal contribution to observed Galactic cosmic rays.

  20. Radio evolution of young supernova remnants

    International Nuclear Information System (INIS)

    Shirkey, R.C. Jr.

    1976-01-01

    A one dimensional spherically symmetric magnetohydrodynamic code was developed to describe the evolution of the dynamical and radio properties of young supernova remnants. The code contains subroutines which treat the development of Rayleigh-Taylor instabilities wherever they arise in the remnant. Under the assumption of quasi-stationary equilibrium (dynamical changes considered slow in comparison to the time it takes the instability to achieve equilibrium) determined that the velocity of the instability is W approximately (a lambda)/sup 1 / 2 /, where a is the Rayleigh-Taylor acceleration and lambda is the wavelength of the instability. Subsequent processing of the kinetic energy of expansion, through turbulence, resulted in an increase in temperature and magnetic field strength. The model was used to analyze instability effects of density inhomogeneities in the interstellar medium on magnetic field amplification. A model was constructed for Cassiopeia A which gave good agreement with the measured dynamics, radio structure, and secular flux density decrease for the remnant. In order to compare observation with theory a computer routine was written that convolves the surface brightness at the source. The resultant convolved surface brightness graph is in good agreement with Rosenberg's observed ''model profile;'' differences between the graphs can be attributed to the asymmetric expansion of Cassiopeia A

  1. Rain, Snow, and Spring Runoff Revisited.

    Science.gov (United States)

    Bohren, Craig F.

    1995-01-01

    Explores the theory behind the correlation between warm rain, rapid snowmelt, and the subsequent runoff using the concepts of enthalpy, thermal transfer, and energy transfer. Concludes that rapid runoff is not a consequence of rain per se but of the high humidities associated with the rain. (JRH)

  2. analysis of rain rate and rain attenuation for earth-space

    African Journals Online (AJOL)

    Rain rate and rain attenuation predictions are vital when designing microwave satellite and terrestrial communication links, such as in the Ku and Ka bands. This paper presents the cumulative distribution functions (CDFs) of the predicted rain rate and rain attenuation for Uyo, Akwa Ibom State (AKS) (Latitude: 4.88°N, ...

  3. Caribbean dry forest networking: an opportunity for conservation

    Science.gov (United States)

    K. Banda-Rodriguez; J. Weintritt; R.T. Pennington

    2016-01-01

    Seasonally dry tropical forest is the most threatened tropical forest in the world. Though its overall plant species diversity is lower than in neighboring biomes such as rain forest, species endemism can be high, and its conservation has often been neglected. Caribbean dry forests face diverse threats including tourism, agriculture, and climate change. The Latin...

  4. Análise discriminante de solos sob diferentes usos em área de Mata Atlântica a partir de atributos da matéria orgânica Discriminant analysis of soils under different land uses in the Atlantic Rain Forest area using organic matter attributes

    Directory of Open Access Journals (Sweden)

    Vinicius de Melo Benites

    2010-08-01

    Full Text Available Na região serrana do Estado do Rio de Janeiro (bioma Mata Atlântica, pequenos agricultores praticam agricultura itinerante no sistema de corte e queima. Neste trabalho, amostras de horizontes superficiais (0 -15 cm de um Latossolo Vermelho-Amarelo sob cinco diferentes coberturas vegetais (Mata Atlântica, cultivo anual, café, banana e pastagem foram coletadas para caracterização química dos teores de carbono nas diferentes frações de substâncias húmicas. As amostras obtidas sob mata e sob pastagem puderam ser nitidamente isoladas das demais pelo modelo discriminante construído. Aquelas representativas do grupo das culturas (banana, café e cultivo foram superposicionadas, indicando haver semelhança entre os atributos relativos à matéria orgânica nos solos sob esses usos. O modelo obtido permitiu classificar corretamente 88% das amostras analisadas. Os atributos ácidos fúlvicos (AF, carbono orgânico (C, nitrogênio total (N e relação C/N foram selecionados pelo modelo, sendo o teor de ácidos fúlvicos o atributo de maior peso relativo. Esse resultado indica que o fracionamento de substâncias húmicas permite a observação de alterações no solo que não são possíveis de serem identificadas pela simples determinação do teor de carbono orgânico total. Pelo padrão de agrupamento das áreas (mata-pastagem e banana-café-cultivo, denotou-se que o uso de fertilizantes pode se relacionar com alterações em atributos indicadores importantes, como o teor de ácidos fúlvicos.In the mountain region of the State of Rio de Janeiro (Atlantic Rain Forest biome, small farmers practice shifting cultivation in the slash and burn system. In this work, soil surfaces samples (0-15cm of a Yellow Red Latossolo under five different vegetal coverings (Atlantic Rain Forest, annual culture, coffee, banana and pasture, had been taken in the small farming area of Bom Jardim RJ for soil chemical characterization and carbon content analysis in

  5. DINÁMICA DE LA BIOMASA AÉREA EN UN BOSQUE PLUVIAL TROPICAL DEL CHOCÓ BIOGEOGRÁFICO DYNAMICS OF TREE ABOVEGROUND BIOMASS IN A TROPICAL RAIN FOREST OF THE CHOCÓ BIOGEOGRÁFICO

    Directory of Open Access Journals (Sweden)

    Harley Quinto Mosquera

    2011-06-01

    Full Text Available El estudio de la biomasa aérea (BA de los bosques tropicales es fundamental para entender el balance del C global en el contexto del cambio climático. La BA se cuantificó en un bosque maduro de Salero (Chocó Biogeográfico, mediante ecuaciones diseñadas para bosques húmedos tropicales, a partir de datos de densidad de madera, diámetro (DAP y altura de árboles (con DAP = 10 cm medidos en dos sub-parcelas permanentes ("E" y "U" de 1 ha, las cuales se monitorearon en los años 1998, 2005 y 2008. La BA fue 237,31 t·ha-1, 259,99 t·ha-1 y 217,97 t·ha-1 respectivamente en la sub-parcela "E". Mientras que en la "U" fue de 178,94 t·ha-1y 179,17 t·ha-1 en los años 2005 y 2008; las diferencias de BA a través del tiempo fueron no significativas. Los incrementos promedios anuales de BA de sobrevivientes fueron 4,42 y 3,18 t·ha-1 año-1 en las sub-parcelas "E" y "U" respectivamente. Además, en sub-parcela "E" en condiciones imperturbadas, se presentó una tasa de incremento neto de la BA (TINBA de 2,61 t·ha-1 año-1, en concordancia con la hipótesis del incremento en la BA en los bosques húmedos tropicales. La productividad primaria neta aérea (PPNA en Salero de carbono fue de 5,21 t· ha-1 año-1, por lo tanto los resultados no apoyaron la hipótesis de la disminución en la productividad de los bosques tropicales con el incremento en la precipitación.The study of the aboveground biomass (AB of tropical forests is fundamental to understand the balance of the global C in the context of the climatic change. We quantified the AB in a mature forest of Salero (Chocó Biogeográfico, by means of equations designed for tropical humid forests, starting from data of wooden density, diameter (D and height of trees (with D = 10 cm measured in two permanent sub-parcels (E and U of 1 hectare (ha, which were measured in the years 1998, 2005 and 2008. Inthis years the AB was of 237.31 t·ha-1, 259.99 t·ha-1 and 217.97 t·ha-1 respectively in the E

  6. Use of Participatory Forest Management as a Strategy for ...

    African Journals Online (AJOL)

    mkhai

    Thirdly, since general mass media, groups such as youth and women, .... which include mobile phones, the internet, email and social networks, broadcast ... Tourism, Pugu and Kazimzumbwi forest reserves (PKFs) are remnants of the oldest ...

  7. Evaluation of the use of scientific information in developing the 1997 Forest plan for the Tongass National Forest.

    Science.gov (United States)

    Fred H. Everest; Douglas N. Swanston; Charles G. Shaw; Winston P. Smith; Kent R. Julin; Stewart D. Allen

    1997-01-01

    The Tongass National Forest is the largest remaining relatively unaltered coastal temperate rain forest in the world. The Forest consists of 16.9 million acres of land distributed across more that 22,000 islands and a narrow strip of mainland in southeast Alaska. The Forest contains abundant timber, wildlife, fisheries, mineral, and scenic resources. The authors...

  8. Non-front-fanged colubroid ("colubrid") snakebites: three cases of local envenoming by the mangrove or ringed cat-eyed snake (Boiga dendrophila; Colubridae, Colubrinae), the Western beaked snake (Rhamphiophis oxyrhynchus; Lamprophiidae, Psammophinae) and the rain forest cat-eyed snake (Leptodeira frenata; Dipsadidae).

    Science.gov (United States)

    Weinstein, S A; Griffin, R; Ismail, A K

    2014-04-01

    Non-front-fanged colubroid snakes (NFFC; formerly and artificially taxonomically assembled as "colubrids") comprise the majority of extant ophidian species. Although the medical risks of bites by a handful of species have been documented, the majority of these snakes have oral products (Duvernoy's secretions, or venoms) with unknown biomedical properties/unverified functions and their potential for causing harm in humans is unknown. Described are three cases of local envenoming from NFFC bites inflicted respectively by the mangrove or ringed cat-eyed snake (Boiga dendrophila, Colubridae), the Western beaked snake (Rhamphiophis oxyrhynchus, Lamprophiidae) and the rain forest cat-eyed snake (Leptodeira frenata, Dipsadidae). The effects ranged from mild pain, edema and erythema to severe pain, progressive edema, and blistering with slowly resolving arthralgia; there were no systemic effects. Although these three taxa occasionally inflict bites with mild to moderate local effects, there is no current evidence of systemic involvement. Two of these cases were reported to one of the authors for medical evaluation, and although verified, thus constitute reliably reported cases, but low-quality evidence. Type-1 local hypersensitivity may contribute to some cases, but most local effects observed or reported in these three cases were consistent with the effects of venom/oral product components.

  9. Measurement of radioactivity in rain

    International Nuclear Information System (INIS)

    Eivindson, T.

    1985-01-01

    The report gives a description of an ion-exchange surveillance- sampler for routine measurements of radioactivity in rain, and how the measurements are performed. Using the nuclides 85 Sr, 131 I and 137 Cs as tracers, experiments have been performed to determine the distribution of radioactivity in the ion-exchange column and the effectiveness of the column as a function of elutriation rate and temperature

  10. Sistema reprodutivo e polinização de Lepidagathis sessilifolia (Pohl Kameyama ex Wassh. & J.R.I. Wood (Acanthaceae, em remanescente florestal da região sudoeste de Mato Grosso, Brasil Breeding system and pollination of Lepidagathis sessilifolia (Pohl Kameyama Wassh ex. & J.R.I.Wood (Acanthaceae in remnant forest in the southwest region of Mato Grosso, Brazil

    Directory of Open Access Journals (Sweden)

    Celice Alexandre Silva

    2012-09-01

    Full Text Available O gênero Lepidagathis apresenta distribuição pantropical com cerca de 100 espécies. No Brasil ocorrem 16 espécies, a maioria nas regiões Centro - Oeste e Sudeste. O estudo foi realizado em sub - bosque de remanescente florestal do município de Tangará da Serra - MT e teve como objetivo analisar a fenologia de floração, descrever a morfologia e biologia floral, verificar os visitantes florais e avaliar o sistema e o sucesso reprodutivo por meio de polinizações manuais. Lepidagathis sessilifolia apresenta inflorescências espiciformes, terminais, com cálice de cor rósea vistosa e corola de coloração branco-rósea. A floração ficou restrita aos meses de março a abril, durante a estação chuvosa. A senescência floral ocorreu após 24 ou 48 horas. A viabilidade dos grãos de pólen foi elevada (92,5%. O único polinizador observado visitando as flores de L. sessilifolia foi a abelha Partamona nhambiquara (Apidae - Meliponini. O sistema reprodutivo misto da espécie é caracterizado pela formação de frutos por meio de agamospermia, autopolinização e polinização cruzada. Esse sistema reprodutivo flexível é vantajoso, pois, garante a manutenção da espécie na área de estudo mesmo na ausência de polinizadores.The genus Lepidagathis has pantropical distribution and about 100 species, 16 occurring in Brazil, mostly in the Midwest and Southeast regions. The research was carried out to evaluate in the understory of a forest remnant in Tangará da Serra County - MT to examine the flowering phenology, describe the floral morphology and biology and verify the floral visitors to evaluate the system and reproductive success through hand pollination tests. Lepidagathis sessilifolia shows spiciform and terminal inflorescence with calyx of pink color and corolla whitish-pink. Flowering was restricted from March to April, during the rainy season. Floral senescence occurred after 24 or 48 hours. The viability of pollen grains was high

  11. Remnant Trees in Enrichment Planted Gaps in Quintana Roo, Mexico: Reasons for Retention and Effects on Seedlings

    Directory of Open Access Journals (Sweden)

    Angélica Navarro-Martínez

    2017-07-01

    Full Text Available Natural forest management in the tropics is often impeded by scarcity of advanced regeneration of commercial species. To supplement natural regeneration in a forest managed by a community in the Selva Maya of Mexico, nursery-grown Swietenia macrophylla seedlings were planted in multiple-tree felling gaps, known as bosquetes. Remnant trees are often left standing in gaps for cultural and economic reasons or due to their official protected status. We focus on these purposefully retained trees and their impacts on planted seedlings. Sampled bosquetes were 400–1800 m2, of which remnant trees covered a mean of 29%. Seedling height growth rates over the first 18 months after out-planting more than doubled with increased canopy openness from 0.09 m year−1 under medium cover to 0.22 m year−1 in full sun. Liana infestations and shoot tip damage were most frequent on seedlings in the open, but, contrary to our expectations, height growth rates were 0.14 m year−1 faster for liana-infested seedlings than non-infested and did not differ between damaged and undamaged seedlings. Apparently the more rapid height growth of well-illuminated seedlings more than compensated for the effects of lianas or shoot tip damage. Despite the abundance of remnant trees and their negative effects on seedling growth, enrichment planting in bosquetes has potential for community-based natural forest management in the tropics in supplementing natural regeneration of commercial species. One obvious recommendation is to leave fewer remnant trees, especially those of commercial species that are non-merchantable due to stem defects and trees retained for no apparent reason, which together constituted half of the remnant crown cover in the sampled bosquetes. Finally, given the rapid growth of lianas and understory palms in large canopy gaps, at least the most vigorous of the planted seedlings should be tended for at least two years.

  12. Tree Regeneration in Church Forests of Ethiopia: Effects of Microsites and Management

    NARCIS (Netherlands)

    Wassie Eshete, A.; Sterck, F.J.; Teketay, D.; Bongers, F.

    2009-01-01

    Tree regeneration is severely hampered in the fragmented afromontane forests of northern Ethiopia. We explored how trees regenerate in remnant forests along the gradient from open field, forest edge to closed sites and canopy gaps inside the forest. We investigated the effects of seed sowing, litter

  13. Utility views of acid rain legislation

    International Nuclear Information System (INIS)

    Katlic, J.E.

    1990-01-01

    The electric utilities consume almost 85% of the coal that is used in the US. The utilities as well as other industries will be seriously affected by revisions currently being considered to the Clean Air Act. We endorse the 10-year scientific National Acid Precipitation Assessment Program (NAPAP) which concludes the acid rain is not an environmental crisis but a long-term problem that needs to be addressed. The extreme views expressed by environmentalists and echoed by the media have been rendered unlikely to be correct assording to the NAPAP director. For example, the report found that the majority of North American forests are healthy. In addition, SO 2 emissions are down while coal use has doubled since the 70's. However, Congress, by considering any of the proposed Clean Air bills, is ignoring the NAPAP results. Experts from all areas are touting the need for the development of a National Energy Policy which would decrease our reliance on foreign oil and capitalize on the resources in abundance here in the United States -- like coal. The President has urged lawmakers to enact measures that would do just that. Yet the Joint Committee of Congress is marching on with revisions to a Clean Air Act that is already working. This will increase the cost of energy across all areas of industry and call a halt to the industrial recovery in this country

  14. Supernova Remnants with Fermi Large Area Telescope

    Directory of Open Access Journals (Sweden)

    Caragiulo M.

    2017-01-01

    Full Text Available The Large Area Telescope (LAT, on-board the Fermi satellite, proved to be, after 8 years of data taking, an excellent instrument to detect and observe Supernova Remnants (SNRs in a range of energies running from few hundred MeV up to few hundred GeV. It provides essential information on physical processes that occur at the source, involving both accelerated leptons and hadrons, in order to understand the mechanisms responsible for the primary Cosmic Ray (CR acceleration. We show the latest results in the observation of Galactic SNRs by Fermi-LAT.

  15. Runaway companions of supernova remnants with Gaia

    Science.gov (United States)

    Boubert, Douglas; Fraser, Morgan; Evans, N. Wyn

    2018-04-01

    It is expected that most massive stars have companions and thus that some core-collapse supernovae should have a runaway companion. The precise astrometry and photometry provided by Gaia allows for the systematic discovery of these runaway companions. We combine a prior on the properties of runaway stars from binary evolution with data from TGAS and APASS to search for runaway stars within ten nearby supernova remnants. We strongly confirm the existing candidate HD 37424 in S147, propose the Be star BD+50 3188 to be associated with HB 21, and suggest tentative candidates for the Cygnus and Monoceros Loops.

  16. VHE Gamma-ray Supernova Remnants

    Energy Technology Data Exchange (ETDEWEB)

    Funk, Stefan; /KIPAC, Menlo Park

    2007-01-22

    Increasing observational evidence gathered especially in X-rays and {gamma}-rays during the course of the last few years support the notion that Supernova remnants (SNRs) are Galactic particle accelerators up to energies close to the ''knee'' in the energy spectrum of Cosmic rays. This review summarizes the current status of {gamma}-ray observations of SNRs. Shell-type as well as plerionic type SNRs are addressed and prospect for observations of these two source classes with the upcoming GLAST satellite in the energy regime above 100 MeV are given.

  17. On neutron star/supernova remnant associations

    OpenAIRE

    Gvaramadze, V. V.

    2000-01-01

    It is pointed out that a cavity supernova (SN) explosion of a moving massive star could result in a significant offset of the neutron star (NS) birth-place from the geometrical centre of the supernova remnant (SNR). Therefore: a) the high implied transverse velocities of a number of NSs (e.g. PSR B1610-50, PSR B1757-24, SGR0525-66) could be reduced; b) the proper motion vector of a NS should not necessarily point away from the geometrical centre of the associated SNR; c) the circle of possibl...

  18. Rain intensity over specific rain thresholds in Athens and Thessaloniki, Greece

    Science.gov (United States)

    Philandras, C. M.; Nastos, P. T.; Kapsomenakis, J.; Repapis, C. C.

    2009-09-01

    It is well documented that climatic change has caused significant impacts in the water cycle and great spatial and temporal variability of the rain events. The rain scarcity in many cases is associated with extreme convective weather resulted in flash floods, which threatens the human life and the existed infrastructure. In this study, the annual mean rain intensity (mm/h) along with the annual number of rain days for rain events over specific rain thresholds, such as 10, 20, 30, 40, 50 mm, in two Greek cities Athens and Thessaloniki, during the period 1930-2007, are examined. The meteorological data, which concern daily rain totals (mm) and duration (h), were acquired from the National Observatory of Athens and from the meteorological station of the University of Thessaloniki. Our findings show that, in Athens, an increase in the number of annual rain days and the mean rain intensity over the aforementioned rain thresholds appears at the end of 1980’s and continues until nowadays. On the contrary, concerning Thessaloniki, a decrease in the rain days is apparent from 1980, while the decrease in the mean rain intensity concerns only the rain thresholds of 10 and 20 mm. This analysis reveals that extreme rain events are more frequent in Athens, which is under a high urbanization rhythm, than in Thessaloniki at the north of Greece. Finally, the patterns of the atmospheric circulation, which are associated with specific extreme cases are analysed, using NCEP reanalysis data.

  19. Remnant cholesterol as a cause of ischemic heart disease

    DEFF Research Database (Denmark)

    Varbo, Anette; Benn, Marianne; Nordestgaard, Børge G

    2014-01-01

    This review focuses on remnant cholesterol as a causal risk factor for ischemic heart disease (IHD), on its definition, measurement, atherogenicity, and levels in high risk patient groups; in addition, present and future pharmacological approaches to lowering remnant cholesterol levels...... are considered. Observational studies show association between elevated levels of remnant cholesterol and increased risk of cardiovascular disease, even when remnant cholesterol levels are defined, measured, or calculated in different ways. In-vitro and animal studies also support the contention that elevated...... levels of remnant cholesterol may cause atherosclerosis same way as elevated levels of low-density lipoprotein (LDL) cholesterol, by cholesterol accumulation in the arterial wall. Genetic studies of variants associated with elevated remnant cholesterol levels show that an increment of 1mmol/L (39mg...

  20. Are crab-type supernova remnants (plerions) short-lived

    International Nuclear Information System (INIS)

    Weiler, K.W.; Panagia, N.

    1978-01-01

    Arguments are given for a possible picture of the origin, maintenance, and lifetimes of the so-called Crab-like supernova remnants. It is suggested that these objects imply the existence of at least two distinct types of supernova events. A possible connection of the remnant types with the optically defined supernovae of Type I and Type II is discussed. Accepting that a pulsar is formed in at least some supernova events, the proposal is made that a rapidly rotating, rapidly slowing pulsar is necessary to create and maintain a Crab-like supernova remnant. Finally, arguments are presented that such a supernova remnant will be relatively short lived with respect to the more common shell-type of supernova remnant, perhaps surviving only 10000-20000 yr before fading into the Galactic background. The name of plerion is proposed for these filled-center supernova remnants and observational possiblities for confirming their nature are suggested. (orig.) [de

  1. Quantitative analysis of seed rain under natural and artificial perches in the Araucaria Forest Análise quantitativa da chuva de sementes sob poleiros naturais e artificiais em Floresta Ombrófila Mista

    Directory of Open Access Journals (Sweden)

    Sandra Bos Mikich

    2010-06-01

    Full Text Available The objective of this study was to compare the efficiency in terms of number of seeds deposited under natural and artificial bird-perches set in degraded areas of Araucaria Forest. Six experimental units were used, each containing seed traps set under natural perches (NP, artificial perches (AP and under open sky (OS. After 12 months of weekly sampling 26880 zoochoric seeds were collected under AP, 5729 under NP, and only seven under OS. Thus, the presence of perches increases dramatically seed deposition and NP are more or as efficient as AP when the effect of deposition area is taken into account.O objetivo deste estudo foi comparar a eficiência de poleiros naturais e artificiais na deposição de
    sementes em áreas degradadas da Floresta com Araucária. Seis unidades experimentais foram utilizadas, cada qual constituída por coletores de sementes instalados sob poleiros naturais (PN, artificiais (PA e a céu aberto (CA. Após 12 meses de coletas semanais, foram recolhidas 26.880 sementes zoocóricas sob os PA, 5.729 sob os PN e 7 nos CA. Portanto, a presença de poleiros incrementa significativamente a chuva de sementes e os PN são tão ou mais eficientes que os PA quando o efeito da área de deposição é levado em consideração.

  2. Rain scavenging of radioactive particles

    International Nuclear Information System (INIS)

    Williams, A.L.

    1975-01-01

    An assessment is made of the rainout of airborne radioactive particles from a nuclear detonation with emphasis on the microphysical removal processes. For submicron particles the scavenging processes examined are Brownian and turbulent diffusion to cloud droplets. For particles larger than 1 μm radius, nucleation scavenging is examined. For various particle size and radioactivity distributions, it is found that from 27 to 99 percent of the radioactivity is attached to cloud droplets and subject to rapid removal by rain. (U.S.)

  3. Spread of acid rain over India

    Science.gov (United States)

    Khemani, L. T.; Momin, G. A.; Rao, P. S. Prakasa; Safai, P. D.; Singh, G.; Kapoor, R. K.

    Rain water and aerosol samples were collected at a few locations representative of urban and non-urban regions in India. Also, rain water samples were collected in and around a coal-fired power plant. All the rain water and aerosol samples were analyzed for major chemical components along with pH. The rain water at all the places of measurement, except near the industrial sources, has been found to be alkaline and was characterized by the presence of excess cations, particularly by Ca 2+. The acid rain near the industrial sources was associated with excess anions, especially SO 42-. The atmospheric aerosols at all the places of measurement were found rich with basic components, suggesting that the alkaline soil dust and fly ash are responsible at present for preventing the spread of acid rain in India.

  4. Acid rain information book. Final report

    International Nuclear Information System (INIS)

    1983-05-01

    Acid rain is one of the most widely publicized environmental issues of the day. The potential consequences of widespread acid rain demand that the phenomenon be carefully evaluated. Review of the literature shows a rapidly growing body of knowledge, but also reveals major gaps in understanding that need to be narrowed. This document discusses aspects of the acid rain phenomenon, points out areas of uncertainty and summarizes current and projected research. The report is organized by a logical progression from sources of pollutants affecting acid rain formation to the atmospheric transport and transformation of those pollutants and finally to the deposition of acid rain, the effects of that deposition, and possible mitigative measures and regulatory options. This information is followed by a discussion of uncertainties in the understanding of the acid rain phenomenon and a description of current and proposed research by responsible government agencies and other concerned organizations

  5. Carbon sink potential of multistrata agroforestry systems at Atlantic Rain Forest Potencial de sistemas agroflorestais multiestrata para sequestro de carbono em áreas de ocorrência de Floresta Atlântica

    Directory of Open Access Journals (Sweden)

    Luís Cláudio Maranhão Froufe

    2011-06-01

    Full Text Available

    Carbon storage of agroforestry systems, regenerated areas, conventional agriculture and pasture was evaluated at Alto Ribeira Valley region, São Paulo State, Brazil, in different compartments of Land-use systems (LUS. In soil, classified as Entisols and Inceptisols, we found similarities among all LUS, dued to their low contents of organic carbon, and similar values of bulk density. The total carbon stocked on land-use systems, greater amounts were determined on regenerated areas (115.78 Mg ha-1, followed by agroforestry systems (75.38 Mg ha-1, agriculture (47.07 Mg ha-1, and pasture (36.01 Mg ha-1. Despite their conservative characteristic, the silvicultural practices of multistrata agroforestry systems have to be improved for forest production and carbon sequestration.

    doi: 10.4336/2011.pfb.31.66.143

    Foi avaliado o estoque de carbono no solo, serapilheira, biomassa arbórea e biomassa herbácea de SAFs multiestratos, em comparação a capoeiras em diferentes estágios de regeneração, sistemas agrícolas convencionais e pastagem, todos na região do Alto Vale do Ribeira, SP. Nos Neossolos e Cambissolos, com baixos teores de carbono orgânico e similaridade dos valores de densidade aparente, as capoeiras contribuíram com 115,78 Mg ha-1 de carbono total estocado, seguidas dos SAFs (75,37 Mg ha-1, das áreas agrícolas (47,07 Mg ha-1 e das pastagens (36,01 Mg ha-1. Apesar do grande potencial de sequestro de carbono dos SAFs, há necessidade de melhoria em suas práticas silviculturais.

    doi: 10.4336/2011.pfb.31.66.143

  6. Acid rain information book. Draft final report

    Energy Technology Data Exchange (ETDEWEB)

    None

    1980-12-01

    Acid rain is one of the most widely publicized environmental issues of the day. The potential consequences of increasingly widespread acid rain demand that this phenomenon be carefully evaluated. Reveiw of the literature shows a rapidly growing body of knowledge, but also reveals major gaps in understanding that need to be narrowed. This document discusses major aspects of the acid rain phenomenon, points out areas of uncertainty, and summarizes current and projected research by responsible government agencies and other concerned organizations.

  7. Economic valuation of forests and nature : a support tool for effective decision making

    NARCIS (Netherlands)

    Lette, H.; Boo, de H.

    2002-01-01

    Included are several case studies, like: The Leuser ecosystem, Sumatra; The Borivili National Park, India; Tropical rain forests, Costa Rica; Mangrove forests, Philippines. This document has been prepared by: IAC and EC-LNV

  8. Acidity and salinity of rain

    Energy Technology Data Exchange (ETDEWEB)

    Gorham, E

    1955-01-01

    Analyses of pH, Na, K, Ca, Mg, HCO/sub 3/, Cl, SO/sub 4/, NO/sub 3/, and PO/sub 4/ are recorded for forty-two rain samples collected in the English Lake District between 14 May and 23 October, 1954. NaCl was often an important constituent, and the main source of Na, Mg, and Cl appeared to be sea-spray. SO/sub 4/ was clearly correlated with soot, and free H/sub 2/SO/sub 4/ frequently accounted for an appreciable proportion of total ions. Ca, K, and SO/sub 4/ were correlated to some extent. HCO/sub 3/ was absent from more than half the samples. NO/sub 3/ and PO/sub 4/ were usually low in concentration. Sea-spray influence appeared greatest in autumn, while industrial pollution reached its highest concentration in spring. The ecological significance of the ions in rain is pointed out.

  9. Mammalian gastrointestinal parasites in rainforest remnants of ...

    Indian Academy of Sciences (India)

    2015-04-27

    Apr 27, 2015 ... parasite recovery by sucrose floatation and sedimentation techniques ..... We thank the Chief Wildlife Warden,Tamil Nadu Forest. Department ... disease is a strong and general service of biodiversity conservation: Response ...

  10. Urachal remnant carcinoma - a rare entity

    Directory of Open Access Journals (Sweden)

    Vanesha Naidu

    2013-06-01

    Full Text Available Primary malignancy of the urachal remnant is a rare neoplasm that accounts for less than 0.01% of all adult cancers, with an estimated annual incidence of 1:5 million. The tumour carries a grave prognosis that attests to its highly aggressive nature. Owing to its extra-peritoneal location, the tumour runs a relatively silent clinical course until late presentation, when most patients display extensive local invasion and metastatic spread. In this report, we highlight a case of primary malignancy of the urachus that on initial clinical evaluation masqueraded as a Sister Mary Joseph’s nodule. Characteristic imaging features, however, proved decisive in establishing the diagnosis of a urachal carcinoma.

  11. A Python Calculator for Supernova Remnant Evolution

    Science.gov (United States)

    Leahy, D. A.; Williams, J. E.

    2017-05-01

    A freely available Python code for modeling supernova remnant (SNR) evolution has been created. This software is intended for two purposes: to understand SNR evolution and to use in modeling observations of SNR for obtaining good estimates of SNR properties. It includes all phases for the standard path of evolution for spherically symmetric SNRs. In addition, alternate evolutionary models are available, including evolution in a cloudy ISM, the fractional energy-loss model, and evolution in a hot low-density ISM. The graphical interface takes in various parameters and produces outputs such as shock radius and velocity versus time, as well as SNR surface brightness profile and spectrum. Some interesting properties of SNR evolution are demonstrated using the program.

  12. THE DRESSMAKER, REMNANTS OF A LIFE

    DEFF Research Database (Denmark)

    Carpe Pérez, Inmaculada Concepción

    2015-01-01

    The Dressmaker, remnants of a life, is a visual representation of our research in animation ,at the Animated Learning Lab, as a means of reflection on the construction of the self and memories. Through the artistic production of motion pictures, an introspection is done in the author’s personal...... knowledge, which help us to reflect upon thoughts, feelings and actions (personal or external). Such experiences shape our personalities and whose emotional balance our happiness depends on. Memories are the left over product out of experiences, constituents of a reality. This is seen and created...... the psychology of the self. Animation, for it’s metaphorical power and playfulness: mix of reality and fantasy, results a very attractive and effective tool to explore different points of view and work the neuroplasticity, facilitator of the physical changes of our brain and our behavior, area of study...

  13. Exosat observations of the Kepler supernova remnant

    International Nuclear Information System (INIS)

    Smith, A.; Peacock, A.; Arnaud, M.; Ballet, J.; Rothenflug, R.

    1989-01-01

    The medium-energy experiment on board Exosat was used to measure the X-ray spectrum of the Kepler supernova remnant over the range 1.5-10 keV. An Fe emission line was clearly resolved with an energy of about 6.5 keV and equivalent width of about 1.8 keV. This was superposed on a continuum with a temperature of 5.0(+3.8, -1.9) keV. The medium-energy spectrum is shown to be consistent with a model in which the Kepler SNR is presently in a Sedov phase of evolution, the 5 keV continuum arises from the shocked interstellar/circumstellar medium, and thermal (but not ionization) equilibrium exists between electrons and ions behind the primary shock front. However, in this case, an overabundance of iron by more than 6 times cosmic is required. 28 refs

  14. On Neutron Star/Supernova Remnant Association

    Science.gov (United States)

    Gvaramadze, V. V.

    It is pointed out that a cavity supernova (SN) explosion of a moving massive star could result in a significant offset of the neutron star (NS) birth-place from the geometrical centre of the supernova remnant (SNR). Therefore: a) the high implied transverse velocities of a number of NSs (e.g. PSR B1610-50, PSR B1706-44, PSR B1757-24, SGR 0526-66) could be reduced; b) the proper motion vector of a NS should not necessarily point away from the geometrical centre of the associated SNR; c) the circle of possible NS/SNR associations could be enlarged. An observational test is discussed, which could provide a determination of the true birth-places of NSs associated with middle-aged SNRs, and thereby provide more reliable estimates of their transverse velocities.

  15. Remnants of occipital vertebrae: proatlas segmentation abnormalities.

    Science.gov (United States)

    Menezes, Arnold H; Fenoy, Kathleen A

    2009-05-01

    Developmental remnants around the foramen magnum, or proatlas segmentation abnormalities, have been recorded in postmortem studies but very rarely in a clinical setting. Because of their rarity, the pathological anatomy has been misunderstood, and treatment has been fraught with failures. The objectives of this prospective study were to understand the correlative anatomy, pathology, and embryology and to recognize the clinical presentation and gain insights on the treatment and management. Our craniovertebral junction (CVJ) database started in 1977 and comprises 5200 cases. This prospective study has retrieval capabilities. Neurodiagnostic studies changed with the evolution of imaging. Seventy-two patients were recognized as having symptomatic proatlas segmentation abnormalities. Ventral bony masses from the clivus or medial occipital condyle occurred in 66% (44/72), lateral or anterolateral compressive masses in 37% (27 of 72 patients), and dorsal bony compression in 17% (12 of 72 patients). Hindbrain herniation was associated in 33%. The age at presentation was 3 to 23 years. Motor symptoms occurred in 72% (52 of 72 patients); palsies in Cranial Nerves IX, X, and XII in 33% (24 of 72 patients); and vertebrobasilar symptoms in 25% (18 of 72 patients). Trauma precipitated symptoms in 55% (40 of 72 patients). The best definition of the abnormality was demonstrated by 3-dimensional computed tomography combined with magnetic resonance imaging. Treatment was aimed at decompression of the pathology and stabilization. Remnants of the occipital vertebrae around the foramen magnum were recognized in 72 of 5200 CVJ cases (7.2%). Magnetic resonance imaging with 3-dimensional computed tomography of the CVJ provides the best definition and understanding of the lesions. Brainstem myelopathy and lower cranial nerve deficits are common clinical presentations in the first and second decades of life. Treatment is aimed at decompression of the pathology and CVJ stabilization.

  16. Benner's remnants: culture, tradition and everyday understanding.

    Science.gov (United States)

    Paley, John

    2002-06-01

    Benner's account of meaning and embodiment in nursing depends on a theory which she has never fully articulated, although she makes numerous allusions to it. Behind the background of shared meanings hovers something called 'culture', which provides each individual with meaning, determines what counts as real for her, and actively hands down interpretation-laden practices. This view is based, Benner claims, on the Heideggerian assumption that the meaning and organization of a culture precedes individual meaning-giving activity. I explore Benner's implicit view of culture, drawing on her published work over 15 years, and offer an appraisal of it. In doing so, I attempt to make sense of some rather strange remarks Benner has recently made about 'remnants' of Cartesian and Kantian thinking being found in the everyday understandings of people with asthma. The concept of culture is developed with reference to both Benner's own work and that of the anthropologist, Clifford Geertz, whose work she frequently cites. Having identified the principal tenets of what we might conveniently call the Benner-Geertz theory, I proceed to interrogate the theory, using the recent anthropological literature -- and, in particular, materialist attacks on the idea of culture as a system of meanings -- in order to cast doubt on it. I also review, very briefly, an alternative way of understanding 'culture', which is not vulnerable to the same criticisms. Benner's implicit theory of culture is revealed, somewhat ironically, as an inverted form of Cartesian dualism. Its intellectual provenance is not Heidegger, who appears to reject it, but the sort of American sociology associated with Talcott Parsons. As a corollary, it is suggested that Benner's 'remnants' analogy cannot be justified, and that the idea of Cartesian and Kantian concepts permeating Western culture, infecting both the providers and receivers of health care, is a myth.

  17. Litterfall, precipitation and nutrient fluxes in a secondary lowland rain forest in Ile-Ife, Nigeria Queda de serrapilheira, precipitação e fluxo de nutrientes em uma floresta pluvial secundária de terras baixas em Il-Ife, Nigéria

    Directory of Open Access Journals (Sweden)

    Modupe B. Oziegbe

    2011-09-01

    Full Text Available Litterfall, precipitation and nutrient fluxes were investigated in a 0.25 ha plot of a secondary lowland rain forest in Ile-Ife, Nigeria, for a period of one year. The study determined the magnitude of nutrient fluxes through (litterfall, incident rainfall, throughfall and stemflow and evaluated the relative importance of these components as pathways of nutrient transport to the soil of this forest. There was a significant monthly variation in litterfall and the highest values of the standing crop of litter occurred from November to March. The concentration of elements in both throughfall and stemflow were higher than those of incidence rainfall. Greater quantities of calcium, magnesium, iron, zinc, copper and nitrogen were deposited annually from the forest floor while greater quantities of mercury, potassium, sodium, phosphorus, lead and sulphur were deposited via precipitation. There was net leaching of all elements from the canopy as precipitation pass through it with the exception of copper, hydrogen ions and lead, which were retained in the canopy. The finding of this study shows that litterfall is the major pathway for the cycling of calcium, magnesium, nitrogen and all micronutrients investigated. Net precipitation is the major pathway for the cycling of potassium, phosphorus, sulphur and trace toxic metals (mercury and lead in the forest.Produção de serapilheira, precipitação e o fluxo de nutrientes foram investigados em uma parcela de 0,25 ha de uma floresta pluvial secundária de terras baixas em Ile-Ife, Nigéria, por um período de um ano. O estudo determinou a magnitude dos fluxos de nutrientes através da serrapilheira, da chuva incidente, da interceptada, da escoada pelo tronco, e também avaliou a importância relativa desses componentes como vias de transporte de nutrientes para o solo desta floresta. Houve variação mensal significativa na produção e acúmulo de serapilheira com maiores valores ocorrendo de novembro a

  18. Supernova remnants and the origin of cosmic rays

    NARCIS (Netherlands)

    Vink, J.

    2014-01-01

    Supernova remnants have long been considered to be the dominant sources of Galactic cosmic rays. For a long time the prime evidence consisted of radio synchrotron radiation from supernova remnants, indicating the presence of electrons with energies of several GeV. However, in order to explain the

  19. Supernova Remnants as the Sources of Galactic Cosmic Rays

    NARCIS (Netherlands)

    Vink, J.

    2013-01-01

    The origin of cosmic rays holds still manymysteries hundred years after they were first discovered. Supernova remnants have for long been the most likely sources of Galactic cosmic rays. I discuss here some recent evidence that suggests that supernova remnants can indeed efficiently accelerate

  20. Relating Eye Activity Measures to Human Controller Remnant Characteristics

    NARCIS (Netherlands)

    Popovici, A; Zaal, P.M.T.; Pool, D.M.; Mulder, M.; Sawaragi, T

    2016-01-01

    This study attempts to partially explain the characteristics of the human perceptual remnant, following Levison’s representation of the remnant as an equivalent observation noise. Eye activity parameters are recorded using an eye tracker in two compensatory tracking tasks in which the visual

  1. Biologia reprodutiva de Canistrum aurantiacum E. Morren (Bromeliaceae em remanescente da Floresta Atlântica, Nordeste do Brasil Reproductive biology of Canistrum aurantiacum E Morren (Bromeliaceae in Atlantic Rain Forest Northeastern Brazil

    Directory of Open Access Journals (Sweden)

    José Alves de Siqueira Filho

    2001-12-01

    Full Text Available Canistrum aurantiacum é uma espécie esciófila, epifítica ou terrestre, componente do sub-bosque de mata e endêmica da Floresta Atlântica dos Estados de Pernambuco e Alagoas. Na Reserva Ecológica de Dois Irmãos (REDI (8º7'30"S e 34º52'30"W a ± 80 msm, em Pernambuco, C. aurantiacum forma densa população, com período de floração de novembro a meados de fevereiro, com pico no ínicio de dezembro, quando chega a abrir, num único dia, até doze flores por indivíduo. Suas flores são tubulosas, com 4 a 5 cm de comprimento. Apresenta síndrome de ornitofilia caracterizada pela antese diurna e ausência de odor nas flores, com corola amarelo-ouro e pela cor vermelha das brácteas involucrais, além do volume e concentração do néctar variando entre 22,6-40,5ml e 26-33%, respectivamente. O pólen e o estigma estão funcionais durante todo o período de antese, que se inicia por volta das 5:20 h da manhã e começam a fechar por volta das 16:00 h. Foram registrados os beija-flores: Chlorostilbon aureoventris e Thalurania watertonii (Trochilinae, Glaucis hirsuta, Phaethornis pretrei e P. ruber (Phaethornitinae. Este último foi observado em intervalos regulares de 10 a 30 min., caracterizando o padrão de visitas do tipo "trap-lining", sendo considerado o principal polinizador da espécie. C. aurantiacum é autocompatível, porém produz baixo número de sementes por fruto nas autopolinizações em relação às polinizações naturais promovidas pelos beija-flores. Pipra rubrocapilla (Pipridae e Tangara faustuosa (Thraupinae foram observados dispersando os frutos de C. aurantiacum. A ornitofilia predominante em Bromeliaceae tem sido interpretada como mecanismo de evolução paralela entre bromélias e beija-flores. Canistrum aurantiacum pode se caracterizar como um exemplo dessa estreita relação.Canistrum aurantiacum, a shade-tolerant species, is either an epiphyte or a terrestrial plant, endemic of the coastal Atlantic forest

  2. [Recurrent neck abscess due to a branchial cleft remnant].

    Science.gov (United States)

    Kruijff, Schelto; Mastboom, Walter J; Vriens, Menno R; Sidhu, Stan B; Delbridge, Leigh W

    2013-01-01

    Abscesses arising from a third or fourth branchial cleft remnant are uncommon clinical entities and are often not recognised in a timely manner. In a 33-year-old female patient with a recurrent abscess in the left side of her neck, the cause turned out to be a fistula in the third branchial cleft remnant. She was treated initially with antibiotics and prednisone without adequate results. When the abscess was finally surgically drained, she became very ill and was admitted to the ICU with sepsis and multiple organ failure. She was discharged from hospital after six weeks. Four months later, a third-branchial cleft remnant was found during pharyngoscopy, immediately after which the cleft remnant fistula was excised and an ipsilateral hemi-thyroidectomy was performed. In young patients with recurring peri-thyroidal abscesses, a branchial cleft remnant should be considered a causative factor; this could avoid high morbidity and a delay in the appropriate treatment.

  3. Comparative effects of simulated acid rain of different ratios of SO42- to NO3- on fine root in subtropical plantation of China.

    Science.gov (United States)

    Liu, Xin; Zhao, Wenrui; Meng, Miaojing; Fu, Zhiyuan; Xu, Linhao; Zha, Yan; Yue, Jianmin; Zhang, Shuifeng; Zhang, Jinchi

    2018-03-15

    The influence of acid rain on forest trees includes direct effects on foliage as well as indirect soil-mediated effects that cause a reduction in fine-root growth. In addition, the concentration of NO 3 - in acid rain increases with the rapidly growing of nitrogen deposition. In this study, we investigated the impact of simulated acid rain with different SO 4 2- /NO 3 - (S/N) ratios, which were 5:1 (S), 1:1 (SN) and 1:5 (N), on fine-root growth from March 2015 to February 2016. Results showed that fine roots were more sensitive to the effects of acid rain than soils in the short-term. Both soil pH and fine root biomass (FRB) significantly decreased as acid rain pH decreased, and also decreased with the percentage of NO 3 - increased in acid rain. Acid rain pH significantly influenced soil total carbon and available potassium in summer. Higher acidity level (pH=2.5), especially of the N treatments, had the strongest inhibitory impact on soil microbial activity after summer. The structural equation modelling results showed that acid rain S/N ratio and pH had stronger direct effects on FRB than indirect effects via changed soil and fine root properties. Fine-root element contents and antioxidant enzymes activities were significantly affected by acid rain S/N ratio and pH during most seasons. Fine-root Al ion content, Ca/Al, Mg/Al ratios and catalase activity were used as better indicators than soil parameters for evaluating the effects of different acid rain S/N ratios and pH on forests. Our results suggest that the ratio of SO 4 2- to NO 3 - in acid rain is an important factor which could affect fine-root growth in subtropical forests of China. Copyright © 2017. Published by Elsevier B.V.

  4. Acid Rain. LC Science Tracer Bullet.

    Science.gov (United States)

    Hollmann, Pauline, Comp.

    The term "acid rain," also called "acid precipitation," generally refers to any precipitation having a pH value of less than 5.6. This guide to the literature on acid rain in the collections of the Library of Congress is not necessarily intended to be a comprehensive bibliography. It is designed to provide the reader with a set…

  5. Rain garden guidelines for southwest Ohio

    Science.gov (United States)

    Rain gardens are a unique and practical landscape feature that can enhance the beauty of home gardens. When properly installed, they are one method of limiting the negative effects of rainfall runoff in urban areas. Indeed, rain gardens turn a "negative" into a "positive" by capt...

  6. Human Ecology: Acid Rain and Public Policy.

    Science.gov (United States)

    Bybee, Rodger W.

    1983-01-01

    A connection between science and society can be seen in the human and ecological dimensions of one contemporary problem: acid rain. Introduces a human ecological theme and relationships between acid rain and public policy, considering scientific understanding and public awareness, scientific research and public policy, and national politics and…

  7. Exploring the Relationship between Prior Knowledge on Rain Gardens and Supports for Adopting Rain Gardens Using a Structural Equation Model

    Directory of Open Access Journals (Sweden)

    Suyeon Kim

    2018-05-01

    Full Text Available The objective of this study was to determine the effect of prior knowledge and visual evaluation on supports for rain garden installations. To achieve this objective, a survey was conducted to obtain prior knowledge of rain gardens, rain garden implementation support ratings, and visual evaluation of rain gardens in 100 visitors of three rain garden sites. Results of the analysis revealed that users’ visual evaluation of rain gardens played a role as a moderator in the relationship between prior knowledge and support for rain garden installations. In other words, education and publicity of rain gardens alone cannot increase support for rain gardens. However, if rain gardens are visually evaluated positively, the effects of education and publicity of rain gardens can be expected. Therefore, to successfully apply a rain garden policy in the future, basic consideration should be given to aesthetics in order to meet visitors’ visual expectations prior to education and publicity of rain gardens.

  8. Tropical savannas and dry forests.

    Science.gov (United States)

    Pennington, R Toby; Lehmann, Caroline E R; Rowland, Lucy M

    2018-05-07

    In the tropics, research, conservation and public attention focus on rain forests, but this neglects that half of the global tropics have a seasonally dry climate. These regions are home to dry forests and savannas (Figures 1 and 2), and are the focus of this Primer. The attention given to rain forests is understandable. Their high species diversity, sheer stature and luxuriance thrill biologists today as much as they did the first explorers in the Age of Discovery. Although dry forest and savanna may make less of a first impression, they support a fascinating diversity of plant strategies to cope with stress and disturbance including fire, drought and herbivory. Savannas played a fundamental role in human evolution, and across Africa and India they support iconic megafauna. Copyright © 2018 Elsevier Ltd. All rights reserved.

  9. Remnant Cholesterol Elicits Arterial Wall Inflammation and a Multilevel Cellular Immune Response in Humans

    NARCIS (Netherlands)

    Bernelot Moens, Sophie J.; Verweij, Simone L.; Schnitzler, Johan G.; Stiekema, Lotte C. A.; Bos, Merijn; Langsted, Anne; Kuijk, Carlijn; Bekkering, Siroon; Voermans, Carlijn; Verberne, Hein J.; Nordestgaard, Børge G.; Stroes, Erik S. G.; Kroon, Jeffrey

    2017-01-01

    Mendelian randomization studies revealed a causal role for remnant cholesterol in cardiovascular disease. Remnant particles accumulate in the arterial wall, potentially propagating local and systemic inflammation. We evaluated the impact of remnant cholesterol on arterial wall inflammation,

  10. Scale Dependence of Spatiotemporal Intermittence of Rain

    Science.gov (United States)

    Kundu, Prasun K.; Siddani, Ravi K.

    2011-01-01

    It is a common experience that rainfall is intermittent in space and time. This is reflected by the fact that the statistics of area- and/or time-averaged rain rate is described by a mixed distribution with a nonzero probability of having a sharp value zero. In this paper we have explored the dependence of the probability of zero rain on the averaging space and time scales in large multiyear data sets based on radar and rain gauge observations. A stretched exponential fannula fits the observed scale dependence of the zero-rain probability. The proposed formula makes it apparent that the space-time support of the rain field is not quite a set of measure zero as is sometimes supposed. We also give an ex.planation of the observed behavior in tenus of a simple probabilistic model based on the premise that rainfall process has an intrinsic memory.

  11. Light-related variation in sapling architecture of three shade-tolerant tree species of the Mexican rain forest Variación arquitectural de árboles juveniles en relación con la luz en tres especies tolerantes a la sombra en una selva húmeda mexicana

    Directory of Open Access Journals (Sweden)

    JOSÉ LUIS MARTÍNEZ-SÁNCHEZ

    2008-09-01

    Full Text Available The crown architecture of three shade-tolerant tree species (two subcanopy and one mid-canopy was analyzed in relation to the light regime of the forest understorey. The aim was to examine to which extent shade-tolerant species variate in their crown architecture. Tree saplings (265 between 50 and 300 cm height, and distributed from understorey to variously-sized canopy gaps, were measured for 13 architectural traits in the lowland rain forest of Los Tuxtlas, México. The analysis showed that the three species changed their architecture as light increased but in a different way. No species conformed to the typical wide-crown type expected for shade-tolerant species, and in contrast they presented some traits of light demanding species. The two sub-canopy species tended to adopt a crown form between a narrow- and wide-crown type, and the mid-canopy species showed more traits of a narrow-crown type. The horizontal crown area appeared as the more related trait to the light and sapling height. It is concluded that despite being shade-tolerant, the studied species make use of better-lit environments in the forest understorey. The crown architecture of shade-tolerant species is not as rigid as originally conceived.Se analizó la arquitectura de la copa de tres especies tolerantes a la sombra (dos del sotobosque y una del dosel medio en relación con el ambiente lumínico del sotobosque de la selva. El objetivo fue examinar el grado de variación que presenta la arquitectura de la copa de especies tolerantes a la sombra. Para esto, se midieron 13 variables arquitecturales en 265 árboles juveniles (50-300 cm de altura distribuidos desde sitios de selva madura hasta claros de diversos tamaños, en la selva húmeda tropical de Los Tuxtlas, México. El análisis mostró que las tres especies cambian la arquitectura de su copa a medida que aumenta la disponibilidad de luz, pero de diferente forma. Ninguna especie presentó el típico modelo de copa plana

  12. Coronal rain in magnetic bipolar weak fields

    Science.gov (United States)

    Xia, C.; Keppens, R.; Fang, X.

    2017-07-01

    Aims: We intend to investigate the underlying physics for the coronal rain phenomenon in a representative bipolar magnetic field, including the formation and the dynamics of coronal rain blobs. Methods: With the MPI-AMRVAC code, we performed three dimensional radiative magnetohydrodynamic (MHD) simulation with strong heating localized on footpoints of magnetic loops after a relaxation to quiet solar atmosphere. Results: Progressive cooling and in-situ condensation starts at the loop top due to radiative thermal instability. The first large-scale condensation on the loop top suffers Rayleigh-Taylor instability and becomes fragmented into smaller blobs. The blobs fall vertically dragging magnetic loops until they reach low-β regions and start to fall along the loops from loop top to loop footpoints. A statistic study of the coronal rain blobs finds that small blobs with masses of less than 1010 g dominate the population. When blobs fall to lower regions along the magnetic loops, they are stretched and develop a non-uniform velocity pattern with an anti-parallel shearing pattern seen to develop along the central axis of the blobs. Synthetic images of simulated coronal rain with Solar Dynamics Observatory Atmospheric Imaging Assembly well resemble real observations presenting dark falling clumps in hot channels and bright rain blobs in a cool channel. We also find density inhomogeneities during a coronal rain "shower", which reflects the observed multi-stranded nature of coronal rain. Movies associated to Figs. 3 and 7 are available at http://www.aanda.org

  13. Generation of Cosmic rays in Historical Supernova Remnants

    Directory of Open Access Journals (Sweden)

    Sinitsyna V.Y.

    2013-06-01

    Full Text Available We present the results of observations of two types of Galactic supernova remnants with the SHALON mirror Cherenkov telescope of Tien-Shan high-mountain Observatory: the shell-type supernova remnants Tycho, Cas A and IC 443; plerions Crab Nebula, 3c58(SN1181 and Geminga (probably plerion. The experimental data have confirmed the prediction of the theory about the hadronic generation mechanism of very high energy (800 GeV - 100 TeV gamma-rays in Tycho's supernova remnant. The data obtainedsuggest that the very high energy gamma-ray emission in the objects being discussedis different in origin.

  14. The importance of Ficus (Moraceae) trees for tropical forest restoration

    DEFF Research Database (Denmark)

    Cottee-Jones, H. Eden W.; Bajpai, Omesh; Chaudhary, Lal B.

    2016-01-01

    Forest restoration is an increasingly important tool to offset and indeed reverse global deforestation rates. One low cost strategy to accelerate forest recovery is conserving scattered native trees that persist across disturbed landscapes and which may act as seedling recruitment foci. Ficus trees...... restoration agents than other remnant trees in disturbed landscapes, and therefore the conservation of these trees should be prioritized....

  15. Revised Distances to 21 Supernova Remnants

    Science.gov (United States)

    Ranasinghe, S.; Leahy, D. A.

    2018-05-01

    We carry out a comprehensive study of H I 21 cm line observations and 13CO line observations of 21 supernova remnants (SNRs). The aim of the study is to search for H I absorption features to obtain kinematic distances in a consistent manner. The 21 SNRs are in the region of sky covered by the Very Large Array Galactic Plane Survey (H I 21 cm observations) and Galactic Ring Survey (13CO line observations). We obtain revised distances for 10 SNRs based on new evidence in the H I and 13CO observations. We revise distances for the other 11 SNRs based on an updated rotation curve and new error analysis. The mean change in distance for the 21 SNRs is ≃25%, i.e., a change of 1.5 kpc compared to a mean distance for the sample of 6.4 kpc. This has a significant impact on interpretation of the physical state of these SNRs. For example, using a Sedov model, age and explosion energy scale as the square of distance, and inferred ISM density scales as distance.

  16. Quantum remnants in the classical limit

    International Nuclear Information System (INIS)

    Kowalski, A.M.; Plastino, A.

    2016-01-01

    We analyze here the common features of two dynamical regimes: a quantum and a classical one. We deal with a well known semi-classic system in its route towards the classical limit, together with its purely classic counterpart. We wish to ascertain i) whether some quantum remnants can be found in the classical limit and ii) the details of the quantum-classic transition. The so-called mutual information is the appropriate quantifier for this task. Additionally, we study the Bandt–Pompe's symbolic patterns that characterize dynamical time series (representative of the semi-classical system under scrutiny) in their evolution towards the classical limit. - Highlights: • We investigate the classical limit (CL) of a well known semi classical model. • The study is made by reference to the Bandt Pompe symbolic approach. • The number and type of associated symbols changes as one proceeds towards the CL. • We ascertain which symbols pertaining to the quantum zone remain in the CL.

  17. Nonthermal Radiation from Supernova Remnant Shocks

    Directory of Open Access Journals (Sweden)

    Hyesung Kang

    2013-09-01

    Full Text Available Most of high energy cosmic rays (CRs are thought to be produced by diffusive shock acceleration (DSA at supernova remnants (SNRs within the Galaxy. Fortunately, nonthermal emissions from CR protons and electrons can provide direct observational evidence for such a model and place strong constraints on the complex nonlinear plasma processes in DSA theory. In this study we calculate the energy spectra of CR protons and electrons in Type Ia SNRs, using time-dependent DSA simulations that incorporate phenomenological models for some wave-particle interactions. We demonstrate that the timedependent evolution of the self-amplified magnetic fields, Alfvénic drift, and escape of the highest energy particles affect the energy spectra of accelerated protons and electrons, and so resulting nonthermal radiation spectrum. Especially, the spectral cutoffs in X-ray and γ-ray emission spectra are regulated by the evolution of the highest energy particles, which are injected at the early phase of SNRs. Thus detailed understandings of nonlinear wave-particle interactions and time-dependent DSA simulations of SNRs are crucial in testing the SNR hypothesis for the origin of Galactic cosmic rays.

  18. Radio emission from embryonic superluminous supernova remnants

    Science.gov (United States)

    Omand, Conor M. B.; Kashiyama, Kazumi; Murase, Kohta

    2018-02-01

    It has been widely argued that Type-I superluminous supernovae (SLSNe-I) are driven by powerful central engines with a long-lasting energy injection after the core-collapse of massive progenitors. One of the popular hypotheses is that the hidden engines are fast-rotating pulsars with a magnetic field of B ˜ 1013-1015 G. Murase, Kashiyama & Mészáros proposed that quasi-steady radio/submm emission from non-thermal electron-positron pairs in nascent pulsar wind nebulae can be used as a relevant counterpart of such pulsar-driven supernovae (SNe). In this work, focusing on the nascent SLSN-I remnants, we examine constraints that can be placed by radio emission. We show that the Atacama Large Millimeter/submillimetre Array can detect the radio nebula from SNe at DL ˜ 1 Gpc in a few years after the explosion, while the Jansky Very Large Array can also detect the counterpart in a few decades. The proposed radio follow-up observation could solve the parameter degeneracy in the pulsar-driven SN model for optical/UV light curves, and could also give us clues to young neutron star scenarios for SLSNe-I and fast radio bursts.

  19. Quantum remnants in the classical limit

    Energy Technology Data Exchange (ETDEWEB)

    Kowalski, A.M., E-mail: kowalski@fisica.unlp.edu.ar [Instituto de Física (IFLP-CCT-Conicet), Universidad Nacional de La Plata, C.C. 727, 1900 La Plata (Argentina); Comision de Investigaciones Científicas (CIC) (Argentina); Plastino, A., E-mail: plastino@fisica.unlp.edu.ar [Instituto de Física (IFLP-CCT-Conicet), Universidad Nacional de La Plata, C.C. 727, 1900 La Plata (Argentina); Argentina' s National Research Council (CONICET) (Argentina); SThAR, EPFL Innovation Park, Lausanne (Switzerland)

    2016-09-16

    We analyze here the common features of two dynamical regimes: a quantum and a classical one. We deal with a well known semi-classic system in its route towards the classical limit, together with its purely classic counterpart. We wish to ascertain i) whether some quantum remnants can be found in the classical limit and ii) the details of the quantum-classic transition. The so-called mutual information is the appropriate quantifier for this task. Additionally, we study the Bandt–Pompe's symbolic patterns that characterize dynamical time series (representative of the semi-classical system under scrutiny) in their evolution towards the classical limit. - Highlights: • We investigate the classical limit (CL) of a well known semi classical model. • The study is made by reference to the Bandt Pompe symbolic approach. • The number and type of associated symbols changes as one proceeds towards the CL. • We ascertain which symbols pertaining to the quantum zone remain in the CL.

  20. Predicting gravitational lensing by stellar remnants

    Science.gov (United States)

    Harding, Alexander J.; Stefano, R. Di; Lépine, S.; Urama, J.; Pham, D.; Baker, C.

    2018-03-01

    Gravitational lensing provides a means to measure mass that does not rely on detecting and analysing light from the lens itself. Compact objects are ideal gravitational lenses, because they have relatively large masses and are dim. In this paper, we describe the prospects for predicting lensing events generated by the local population of compact objects, consisting of 250 neutron stars, five black holes, and ≈35 000 white dwarfs. By focusing on a population of nearby compact objects with measured proper motions and known distances from us, we can measure their masses by studying the characteristics of any lensing event they generate. Here, we concentrate on shifts in the position of a background source due to lensing by a foreground compact object. With Hubble Space Telescope, JWST, and Gaia, measurable centroid shifts caused by lensing are relatively frequent occurrences. We find that 30-50 detectable events per decade are expected for white dwarfs. Because relatively few neutron stars and black holes have measured distances and proper motions, it is more difficult to compute realistic rates for them. However, we show that at least one isolated neutron star has likely produced detectable events during the past several decades. This work is particularly relevant to the upcoming data releases by the Gaia mission and also to data that will be collected by JWST. Monitoring predicted microlensing events will not only help to determine the masses of compact objects, but will also potentially discover dim companions to these stellar remnants, including orbiting exoplanets.

  1. Bioremediation of a crude oil polluted tropical rain forest soil ...

    African Journals Online (AJOL)

    These results suggest that Biostimulation with tilling (nutrient enhanced in-situ bioremediation) and or the combination ofBiostimulation and Bioaugumentation with indigenous hydrocarbon utilizers would be effective in the remediation of crude oil polluted tropical soils. Key Words: Bioremediation, Bioaugumentation, ...

  2. Decoupled leaf and stem economics in rain forest trees

    NARCIS (Netherlands)

    Baraloto, C.; Paine, C.E.T.; Poorter, L.; Beauchene, J.; Bonal, D.; Domenach, A.M.; Herault, B.; Patiño, S.; Roggy, J.C.; Chave, J.

    2010-01-01

    Cross-species analyses of plant functional traits have shed light on factors contributing to differences in performance and distribution, but to date most studies have focused on either leaves or stems. We extend these tissue-specific analyses of functional strategy towards a whole-plant approach by

  3. Humidity estimate for the middle Eocene Arctic rain forest

    Science.gov (United States)

    Jahren, A. Hope; Silveira Lobo Sternberg, Leonel

    2003-05-01

    The exquisite preservation of fossilized Metasequoia trees that grew near 80°N latitude during the middle Eocene (ca. 45 Ma) in Nunavut, Canada, allowed for δD and δ18O analyses of cellulose, techniques previously restricted to wood <30,000 yr old. From the isotopic results, we determined that the middle Eocene Arctic atmosphere contained ˜2× the water found in the region's atmosphere today. This water vapor contributed to a middle Eocene greenhouse effect that insulated the polar region during dark polar winters.

  4. Canopy assemblages of ants in a New Guinea rain forest

    Czech Academy of Sciences Publication Activity Database

    Janda, Milan; Konečná, M.

    2011-01-01

    Roč. 27, č. 1 (2011), s. 83-91 ISSN 0266-4674 R&D Projects: GA AV ČR KJB612230701; GA MŠk LC06073; GA MŠk ME09082; GA ČR GD206/08/H044; GA ČR GA206/09/0115; GA ČR GAP505/10/0673 Institutional research plan: CEZ:AV0Z50070508 Keywords : bait traps * canopy * dominance Subject RIV: EH - Ecology, Behaviour Impact factor: 1.401, year: 2011

  5. Evidence of Late Palaeocene-Early Eocene equatorial rain forest ...

    Indian Academy of Sciences (India)

    Prakash

    2009-11-02

    Nov 2, 2009 ... influx of CO2 during early Cenozoic times (Kent and Muttoni. 2008), besides ... Palaeocene – Eocene lignite and coal deposits of India. .... journey of the Indian subcontinent and massive outpouring ..... ice age (Plana 2004).

  6. Repeated insect outbreaks promote multi-cohort aspen mixedwood forests in Northern Minnesota, USA

    Science.gov (United States)

    Michael Reinikainen; Anthony W. D' Amato; Shawn. Fraver

    2012-01-01

    Characterizing the timing, severity, and agents of historic forest disturbances is critical to developing management and conservation strategies based on natural processes. Typically such information is derived from retrospective studies of remnant old-growth forests; however, this approach has limited application in regions dominated by secondary forests heavily...

  7. Natural forest regeneration and ecological restoration in human-modified tropical landscapes

    NARCIS (Netherlands)

    Martínez-Ramos, Miguel; Pingarroni, Aline; Rodríguez-Velázquez, Jorge; Toledo-Chelala, Lilibeth; Zermeño-Hernández, Isela; Bongers, Frans

    2016-01-01

    In human-modified tropical landscapes (HMLs) the conservation of biodiversity, functions and services of forest ecosystems depends on persistence of old growth forest remnants, forest regeneration in abandoned agricultural fields, and restoration of degraded lands. Understanding the impacts of

  8. Cystic duct remnant mucocele in a liver transplant recipient

    Energy Technology Data Exchange (ETDEWEB)

    Ahlawat, Sushil K. [Georgetown University Hospital, Department of Medicine, Division of Gastroenterology, Washington, DC (United States); University of Medicine and Dentistry of New Jersey, New Jersey Medical School, Newark, NJ (United States); Fishbien, Thomas M. [Georgetown University Hospital, Department of Medicine, Division of Gastroenterology, Washington, DC (United States); Haddad, Nadim G. [Georgetown University Hospital, Department of Surgery, Division of Transplant Surgery, Washington, DC (United States)

    2008-08-15

    Cystic duct remnant mucocele is an extremely rare complication of liver transplantation in children. Surgical correction is usually required for cystic duct remnant mucocele when it causes biliary obstruction. We describe a 14-month-old liver transplant recipient who presented with biliary obstruction 1 month after orthotopic liver transplantation with an end-to-end choledochocholedocal biliary anastomosis for hepatoblastoma. US, CT and cholangiography findings were consistent with mucocele of the allograft cystic duct remnant. Surgery was not needed in our patient because the mucocele and biliary obstruction had resolved on repeat imaging most likely due to guidewire manipulation during cholangiography, resulting in opening of the cystic duct remnant orifice and drainage into the common duct. (orig.)

  9. Cystic duct remnant mucocele in a liver transplant recipient

    International Nuclear Information System (INIS)

    Ahlawat, Sushil K.; Fishbien, Thomas M.; Haddad, Nadim G.

    2008-01-01

    Cystic duct remnant mucocele is an extremely rare complication of liver transplantation in children. Surgical correction is usually required for cystic duct remnant mucocele when it causes biliary obstruction. We describe a 14-month-old liver transplant recipient who presented with biliary obstruction 1 month after orthotopic liver transplantation with an end-to-end choledochocholedocal biliary anastomosis for hepatoblastoma. US, CT and cholangiography findings were consistent with mucocele of the allograft cystic duct remnant. Surgery was not needed in our patient because the mucocele and biliary obstruction had resolved on repeat imaging most likely due to guidewire manipulation during cholangiography, resulting in opening of the cystic duct remnant orifice and drainage into the common duct. (orig.)

  10. Soak Up the Rain Customizable Outreach Tools

    Science.gov (United States)

    Get customizable Soak Up the Rain business card, posters, & a banner that can be downloaded & copied for use by citizens, municipalities, watershed & planning organizations & others in their stormwater/green infrastructure education & outreach efforts.

  11. NESDIS Blended Rain Rate (RR) Products

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The blended Rain Rate (RR) product is derived from multiple sensors/satellites. The blended products were merged from polar-orbiting and geostationary satellite...

  12. Acid rain information book. Second edition

    International Nuclear Information System (INIS)

    1983-05-01

    Potential consequences of widespread acid precipitation are reviewed through an extensive literature search. Major aspects of the acid rain phenomena are discussed, areas of uncertainty identified, and current research summarized

  13. Rain Erosion/Measurement Impact Laboratory

    Data.gov (United States)

    Federal Laboratory Consortium — The FARM Rain Erosion/Impact Measurement Lab develops solutions for deficiencies in the ability of materials, coatings and designs to withstand a severe operational...

  14. 7746 CONCENTRATIONS OF FORMALDEHYDE IN RAIN WATERS ...

    African Journals Online (AJOL)

    Win7Ent

    2013-06-03

    Jun 3, 2013 ... The chromotropic acid method described by the. National Institute for ... concentration range of the formaldehyde in the rain waters varied from month to month throughout the six ... vicinity of vegetation [3]. Formaldehyde is the ...

  15. Hydrodynamic Simulations of Kepler's Supernova Remnant

    Science.gov (United States)

    Sullivan, Jessica; Blondin, John; Borkowski, Kazik; Reynolds, Stephen

    2018-01-01

    Kepler’s supernova remnant contains unusual features that strongly suggest an origin in a single-degenerate Type Ia explosion, including anisotropic circumstellar medium (CSM), a strong brightness gradient, and spatially varying expansion proper motions. We present 3Dhydrodynamic simulations to test a picture in which Kepler's progenitor binary emitted a strong asymmetric wind, densest in the orbital plane, while the system moved at high velocity through the ISM. We simulate the creation of the presupernova environment as well as the supernova blast wave, using the VH-1 grid-based hydrodynamics code. We first modeled an anisotropic wind to create an asymmetric bowshock around the progenitor, then the blast wave from thesupernova. The final simulation places both previous model pieces onto a single grid and allows the blast wave to expand into the bowshock. Models were completed on a Yin-Yang grids with matching angular resolutions. By manipulating parameters that control the asymmetry of the system, we attempted to find conditions that recreated the current state of Kepler. We analyzed these models by comparing images of Kepler from the Chandra X-ray Observatory to line-of-sight projections from the model results. We also present comparisons of simulated expansion velocities with recent observations of X-ray proper motions from Chandra images. We were able to produce models that contained similar features to those seen in Kepler. We find the greatest resemblance to Kepler images with a presupernova wind with an equator-to-pole density contrast of 3 and a moderately disk-like CSM at a 5° angle between equatorial plane and system motion.

  16. Influence of acid rain and organic matter on the adsorption of trace elements on soil

    International Nuclear Information System (INIS)

    Wang, H.; Ambe, S.; Takematsu, N.; Ambe, F.

    1998-01-01

    Acid rain has become one of the most serious environmental problems. Soil loses its buffering capacity by long exposure to acid rain, and the soil pH value decreases significantly. The acidification of the soil disturbs the adsorption equilibrium of many elements in the soil-water system. Soil is a very complex heterogeneous system, primarily consisting of clay minerals, hydrous oxides and polymeric organic substances, which possess their own characteristic element-adsorbing properties. On the other hand, the intrinsic properties of elements are reflected in their adsorption process as a matter of course. Therefore, both the effects of the pH of acid rain and that of the components of the soil on the adsorption of different elements should be studied when the adsorption process in acid soils is to be clarified. Although leaching of major cations in soil, such as Ca 2+ , Mg 2+ and Al 3+ , by acid rain, has been extensively studied, relatively little attention has been focused on trace elements which can also seriously affect the ecological system. We studied the acid rain effects on element adsorption by kaolin, forest soil, black soil, and also these soils with Fe- and Mn-oxides or organic matter selectively removed by using the radioactive multitracer technique. (author)

  17. Chemical characterization of fog and rain water collected at the eastern Andes cordillera

    Directory of Open Access Journals (Sweden)

    E. Beiderwieden

    2005-01-01

    Full Text Available During a three month period in 2003 and 2004, the chemistry of fog and rainwater were studied at the 'El Tiro' site in a tropical mountain forest ecosystem in Ecuador, South America. The fogwater samples were collected using a passive fog collector, and for the rain water, a standard rain sampler was employed. For all samples, electric conductivity, pH, and the concentrations of NH4+, K+, Na+, Ca2+, Mg2+, Cl−, NO3−, PO43−, and SO42− were measured. For each fog sample, a 5 day back trajectory was calculated by the use of the HYSPLIT model. Two types of trajectories occurred. One type was characterized by advection of air masses from the East over the Amazonian basin, the other trajectory arrived one from the West after significant travel time over the Pacific Ocean. We found considerably higher ion concentrations in fogwater samples than in rain samples. Median pH values are 4.58 for fog water, and 5.26 for the rain samples, respectively. The median electric conductivity was 23 μS cm−1 for the fog and 6 μS cm−1 for the rain. The continent samples exhibit higher concentrations of most ions as compared to the pacific samples, but these differences could not be detected statistically.

  18. Chemical characterization of fog and rain water collected at the eastern Andes cordillera

    Science.gov (United States)

    Beiderwieden, E.; Wrzesinsky, T.; Klemm, O.

    2005-09-01

    During a three month period in 2003 and 2004, the chemistry of fog and rainwater were studied at the "El Tiro" site in a tropical mountain forest ecosystem in Ecuador, South America. The fogwater samples were collected using a passive fog collector, and for the rain water, a standard rain sampler was employed. For all samples, electric conductivity, pH, and the concentrations of NH4+, K+, Na+, Ca2+, Mg2+, Cl-, NO3-, PO43-, and SO42- were measured. For each fog sample, a 5 day back trajectory was calculated by the use of the HYSPLIT model. Two types of trajectories occurred. One type was characterized by advection of air masses from the East over the Amazonian basin, the other trajectory arrived one from the West after significant travel time over the Pacific Ocean. We found considerably higher ion concentrations in fogwater samples than in rain samples. Median pH values are 4.58 for fog water, and 5.26 for the rain samples, respectively. The median electric conductivity was 23 μS cm-1 for the fog and 6 μS cm-1 for the rain. The continent samples exhibit higher concentrations of most ions as compared to the pacific samples, but these differences could not be detected statistically.

  19. Supernova Remnant Observations with Micro-X

    Science.gov (United States)

    Figueroa, Enectali

    Micro-X is a sounding rocket payload that combines an X-ray microcalorimeter with an imaging mirror to offer breakthrough science from high spectral resolution observations of extended X-ray sources. This payload has been in design and development for the last five years and is now completely built and undergoing integration; its first flight will be in November, 2012, as part of our current NASA award. This four-year follow-on proposal seeks funding for: (1) analysis of the first flight data, (2) the second flight and its data analysis, (3) development of payload upgrades and launch of the third flight, and (4) third flight data analysis. The scientific payload consists of a Transition Edge Sensor (TES) microcalorimeter array at the focus of a flight-proven conical imaging mirror. Micro-X capitalizes on three decades of NASA investment in the development of microcalorimeters and X-ray imaging optics. Micro-X offers a unique combination of bandpass, collecting area, and spectral and angular resolution. The spectral resolution goal across the 0.2 - 3.0 keV band is 2 - 4 eV Full-Width at Half Maximum (FWHM). The measured angular resolution of the mirror is 2.4 arcminute Half-Power Diameter (HPD). The effective area of the mirror, 300 square centimeters at 1 keV, is sufficient to provide observations of unprecedented quality of several astrophysical X-ray sources, even in a brief sounding rocket exposure of 300 sec. Our scientific program for this proposal will focus on supernova remnants (SNRs), whose spatial extent has made high-energy resolution observations with grating instruments extremely challenging. X-ray observations of SNRs with microcalorimeters will enable the study of the detailed atomic physics of the plasma; the determination of temperature, turbulence, and elemental abundances; and in conjunction with historical data, full three dimensional mapping of the kinematics of the remnant. These capabilities will open new avenues towards understanding the

  20. Acid rain may cause senile dementia

    Energy Technology Data Exchange (ETDEWEB)

    Pearce, F

    1985-04-25

    Aluminium, released from the soil by acid rain, may be a cause of several forms of senile dementia including Parkinson's disease and Alzheimer's disease. Many upland reservoirs, fed by acid rain, supply homes with water laced with significant amounts of aluminium. Studies in the Pacific have shown that communities living on soils that are extremely rich in bauxite, the rock containing aluminium, have a very high incidence of Alzheimer's disease.