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Sample records for tropical woody plants

  1. Accumulation of 137Cs and 40K in aboveground organs of tropical woody fruit plants

    International Nuclear Information System (INIS)

    Anjos, R.M.; Sanches, N.; Macario, K.D.; Rizzotto, M.; Velasco, H.; Valladares, D.L.

    2009-01-01

    Distribution of 40 K and 137 Cs in tissues of the Citrus aurantifolia was measured by gamma spectrometry. A simple theoretical model is also proposed to describe the temporal evolution of 40 K activity concentration in such tropical woody fruit species. This model exhibits close agreement with the 40 K experimental results, in the leaf growing and fruit ripening processes of lemon trees. (author)

  2. β-Diversity of functional groups of woody plants in a tropical dry forest in Yucatan.

    Directory of Open Access Journals (Sweden)

    Jorge Omar López-Martínez

    Full Text Available Two main theories have attempted to explain variation in plant species composition (β-diversity. Niche theory proposes that most of the variation is related to environment (environmental filtering, whereas neutral theory posits that dispersal limitation is the main driver of β-diversity. In this study, we first explored how α- and β-diversity of plant functional groups defined by growth form (trees, shrubs and lianas, which represent different strategies of resource partitioning, and dispersal syndrome (autochory, anemochory and zoochory, which represent differences in dispersal limitation vary with successional age and topographic position in a tropical dry forest. Second, we examined the effects of environmental, spatial, and spatially-structured environmental factors on β-diversity of functional groups; we used the spatial structure of sampling sites as a proxy for dispersal limitation, and elevation, soil properties and forest stand age as indicators of environmental filtering. We recorded 200 species and 22,245 individuals in 276 plots; 120 species were trees, 41 shrubs and 39 lianas. We found that β-diversity was highest for shrubs, intermediate for lianas and lowest for trees, and was slightly higher for zoochorous than for autochorous and anemochorous species. All three dispersal syndromes, trees and shrubs varied in composition among vegetation classes (successional age and topographic position, whilst lianas did not. β-diversity was influenced mostly by proxies of environmental filtering, except for shrubs, for which the influence of dispersal limitation was more important. Stand age and topography significantly influenced α-diversity across functional groups, but showed a low influence on β-diversity -possibly due to the counterbalancing effect of resprouting on plant distribution and composition. Our results show that considering different plant functional groups reveals important differences in both α- and

  3. Different hydraulic traits of woody plants from tropical forests with contrasting soil water availability.

    Science.gov (United States)

    Zhu, Shi-Dan; Chen, Ya-Jun; Fu, Pei-Li; Cao, Kun-Fang

    2017-11-01

    In southwestern China, tropical karst forests (KF) and non-karst rain forests (NKF) have different species composition and forest structure owing to contrasting soil water availability, but with a few species that occur in both forests. Plant hydraulic traits are important for understanding the species' distribution patterns in these two forest types, but related studies are rare. In this study, we investigated hydraulic conductivity, vulnerability to drought-induced cavitation and wood anatomy of 23 abundant and typical woody species from a KF and a neighboring NKF, as well as two Bauhinia liana species common to both forests. We found that the KF species tended to have higher sapwood density, smaller vessel diameter, lower specific hydraulic conductivity (ks) and leaf to sapwood area ratio, and were more resistant to cavitation than NKF species. Across the 23 species distinctly occurring in either KF or NKF, there was a significant tradeoff between hydraulic efficiency and safety, which might be an underlying mechanism for distributions of these species across the two forests. Interestingly, by possessing rather large and long vessels, the two Bauhinia liana species had extremely high ks but were also high resistance to cavitation (escaping hydraulic tradeoff). This might be partially due to their distinctly dimorphic vessels, but contribute to their wide occurrence in both forests. © The Author 2017. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  4. Seasonal dynamics in photosynthesis of woody plants at the northern limit of Asian tropics: potential role of fog in maintaining tropical rainforests and agriculture in Southwest China.

    Science.gov (United States)

    Zhang, Yong-Jiang; Holbrook, N Michele; Cao, Kun-Fang

    2014-10-01

    The lowland tropical rainforests in Xishuangbanna, Southwest (SW) China, mark the northern limit of Asian tropics. Fog has been hypothesized to play a role in maintaining rainforests and tropical crop production in this region, but the physiological mechanism has not been studied. The goals of this study were to characterize the seasonal dynamics in photosynthesis and to assess the potential for fog to mitigate chilling-induced photodamage for tropical trees and crops in Xishuangbanna. We measured seasonal dynamics in light-saturated net photosynthetic rate (Aa), stomatal conductance (gs), intercellular CO2 concentration, quantum yield of Photosystem II (Fv/Fm) and maximum P700 changes (Pm; indicates the amount of active PSI complex), as well as chilling resistance and fog (light/shading) effects on low temperature-induced decline in Fv/Fm and Pm for native tree and introduced lower latitude tree or woody shrub species grown in a tropical botanical garden. Despite significant decreases in Aa, gs, Pm and Fv/Fm, most species maintained considerably high Aa during the cool season (2.51-14.6 μmol m(-2) s(-1)). Shaded leaves exposed to seasonal low temperatures had higher Fv/Fm than sun-exposed leaves in the cool season. All species could tolerate 1.4 °C in the dark, whereas a combined treatment of low temperature and high light caused a distinctly faster decline in Pm and Fv/Fm compared with low temperature treatment alone. Because fog persistence avoids or shortens the duration of high light condition in the morning when the temperatures are still low, our results provide support for the hypothesis that fog reduces chilling damage to tropical plants in this region and thus plays a role in maintaining tropical rainforests and agriculture in SW China. © The Author 2014. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  5. Physiology of woody plants

    CERN Document Server

    Hazewinkel, Michiel; Pallardy, Stephen G

    1996-01-01

    This completely revised classic volume is an up-to-date synthesis of the intensive research devoted to woody plants. Intended primarily as a text for students and a reference for researchers, this interdisciplinary book should be useful to a broad range of scientists from agroforesters, agronomists, and arborists to plant pathologists, ecophysiologists, and soil scientists. Anyone interested in plant physiology will find this text invaluable. Key Features * Includes supplementary chapter summaries and lists of general references * Provides a solid foundation of reference information * Thoroughly updated classic text/reference.

  6. Responses of seedlings of tropical woody plants to environmental stresses with emphasis on Theobroma cacao and Hevea brasiliensis

    Energy Technology Data Exchange (ETDEWEB)

    Sena Gomes, A.R.

    1987-01-01

    Relative humidity, flooding, temperature, wind, and SO/sub 2/ variously influenced physiological processes and growth of tropical woody plants, with emphasis on three Theobroma cacao varieties and three Hevea brasiliensis families. Stomata were smaller and more numerous in Theobroma than in Hevea. In Theobroma, but not Heavea, stomatal frequency decreased from the leaf base to the apex and from the midrib outward. Stomata of Theobroma cacao var. Catongo opened in high relative humidity (RH) and closed in low RH. The more open stomata in high RH were associated with high rates of photosynthesis, low leaf water potential, high water use efficiency (WUE), and low transpiration rate (TR). Variations in TR and WUE were correlated with changes in vapor pressure deficit. Other responses included stomatal closure, decreased chlorophyll content, leaf epinasty, production of hypertrophied lenticels and adventitious roots, and acceleration of ethylene production. Responses to flooding varied with species, Theobroma varieties and Hevea families. Effects of temperature regimes on growth varied with species, varieties and families, plant parts, growth parameters, and time of harvesting. Optimal temperatures for dry weight increase of stems or roots of Theobroma cacao var. Comum were 22.2 C; and 33.3 C for dry weight increase or relative growth rates of leaves or seedlings. Optimal temperatures for growth varied for Hevea families. Wind injured leaves of Theobroma cacao, with more injury by wind of 6.0 than 3.0 m s/sup -1/. Stomata were more open on windy than on calm days, but tended to close at high wind speeds. Wind lowered transpiration rate but the reduction was not correlated with leaf dehydration. SO/sub 2/ at 0.5, 1.0, or 1.5 ppm for 24 h did not injure Theobroma leaves but reduced dry weight increment of leaves of var. Catongo but not Catongo/Sial.

  7. Aluminium exclusion and aluminium tolerance in woody plants

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    Ivano eBrunner

    2013-06-01

    Full Text Available The aluminium (Al cation Al3+ is highly rhizotoxic and is a major stress factor to plants on acid soils, which cover large areas of tropical and boreal regions. Many woody plant species are native to acid soils and are well adapted to high Al3+ conditions. In tropical regions, both woody Al accumulator and non-Al accumulator plants occur, whereas in boreal regions woody plants are non-Al accumulators. The mechanisms of these adaptations can be divided into those that facilitate the exclusion of Al3+ from root cells (exclusion mechanisms and those that enable plants to tolerate Al3+ once it has entered the root and shoot symplast (internal tolerance mechanisms. The biochemical and molecular basis of these mechanisms have been intensively studied in several crop plants and the model plant Arabidopsis. In this review, we examine the current understanding of Al3+ exclusion and tolerance mechanisms from woody plants. In addition, we discuss the ecology of woody non-Al accumulator and Al accumulator plants, and present examples of Al3+ adaptations in woody plant populations. This paper complements previous reviews focusing on crop plants and provides insights into evolutionary processes operating in plant communities that are widespread on acid soils.

  8. Aluminum exclusion and aluminum tolerance in woody plants.

    Science.gov (United States)

    Brunner, Ivano; Sperisen, Christoph

    2013-01-01

    The aluminum (Al) cation Al(3) (+) is highly rhizotoxic and is a major stress factor to plants on acid soils, which cover large areas of tropical and boreal regions. Many woody plant species are native to acid soils and are well adapted to high Al(3) (+) conditions. In tropical regions, both woody Al accumulator and non-Al accumulator plants occur, whereas in boreal regions woody plants are non-Al accumulators. The mechanisms of these adaptations can be divided into those that facilitate the exclusion of Al(3) (+) from root cells (exclusion mechanisms) and those that enable plants to tolerate Al(3) (+) once it has entered the root and shoot symplast (internal tolerance mechanisms). The biochemical and molecular basis of these mechanisms have been intensively studied in several crop plants and the model plant Arabidopsis. In this review, we examine the current understanding of Al(3) (+) exclusion and tolerance mechanisms from woody plants. In addition, we discuss the ecology of woody non-Al accumulator and Al accumulator plants, and present examples of Al(3) (+) adaptations in woody plant populations. This paper complements previous reviews focusing on crop plants and provides insights into evolutionary processes operating in plant communities that are widespread on acid soils.

  9. Frost resistance in alpine woody plants.

    Science.gov (United States)

    Neuner, Gilbert

    2014-01-01

    This report provides a brief review of key findings related to frost resistance in alpine woody plant species, summarizes data on their frost resistance, highlights the importance of freeze avoidance mechanisms, and indicates areas of future research. Freezing temperatures are possible throughout the whole growing period in the alpine life zone. Frost severity, comprised of both intensity and duration, becomes greater with increasing elevation and, there is also a greater probability, that small statured woody plants, may be insulated by snow cover. Several frost survival mechanisms have evolved in woody alpine plants in response to these environmental conditions. Examples of tolerance to extracellular freezing and freeze dehydration, life cycles that allow species to escape frost, and freeze avoidance mechanisms can all be found. Despite their specific adaption to the alpine environment, frost damage can occur in spring, while all alpine woody plants have a low risk of frost damage in winter. Experimental evidence indicates that premature deacclimation in Pinus cembra in the spring, and a limited ability of many species of alpine woody shrubs to rapidly reacclimate when they lose snow cover, resulting in reduced levels of frost resistance in the spring, may be particularly critical under the projected changes in climate. In this review, frost resistance and specific frost survival mechanisms of different organs (leaves, stems, vegetative and reproductive over-wintering buds, flowers, and fruits) and tissues are compared. The seasonal dynamics of frost resistance of leaves of trees, as opposed to woody shrubs, is also discussed. The ability of some tissues and organs to avoid freezing by supercooling, as visualized by high resolution infrared thermography, are also provided. Collectively, the report provides a review of the complex and diverse ways that woody plants survive in the frost dominated environment of the alpine life zone.

  10. Frost resistance of alpine woody plants

    Directory of Open Access Journals (Sweden)

    Gilbert eNeuner

    2014-12-01

    Full Text Available This report provides a brief review of key findings related to frost resistance in alpine woody plant species, summarizes data on their frost resistance, highlights the importance of freeze avoidance mechanisms, and indicates areas of future research.Freezing temperatures are possible throughout the whole growing period in the alpine life zone. Frost severity, comprised of both intensity and duration, becomes greater with increasing elevation and, there is also a greater probability, that small statured woody plants, may be insulated by snow cover.Several frost survival mechanisms have evolved in woody alpine plants in response to these environmental conditions. Examples of tolerance to extracellular freezing and freeze dehydration, life cycles that allow species to escape frost, and freeze avoidance mechanisms can all be found. Despite their specific adaption to the alpine environment, frost damage can occur in spring, while all alpine woody plants have a low risk of frost damage in winter. Experimental evidence indicates that premature deacclimation in Pinus cembra in the spring, and a limited ability of many species of alpine woody shrubs to rapidly reacclimate when they lose snow cover, resulting in reduced levels of frost resistance in the spring, may be particularly critical under the projected changes in climate.In this review, frost resistance and specific frost survival mechanisms of different organs (leaves, stems, vegetative and reproductive over-wintering buds, flowers and fruits and tissues are compared. The seasonal dynamics of frost resistance of leaves of trees, as opposed to woody shrubs, is also discussed. The ability of some tissues and organs to avoid freezing by supercooling, as visualized by high resolution infrared thermography, are also provided. Collectively, the report provides a review of the complex and diverse ways that woody plants survive in the frost dominated environment of the alpine life zone.

  11. Woody plants and land use

    International Nuclear Information System (INIS)

    Huxley, P.A.

    1982-01-01

    The importance of woody species in land use systems has recently gained international attention. In addition to the production of food and fuelwood, trees can maintain or improve the fertility status of the soil and conserve both soil and water. The use of multipurpose trees in land use system and the important role of trees in association with other crops is now recognized. The methods of scientifically studying such systems, and of manipulating them to improve their productivity or net utility have not been well developed. This introductory paper documents the role of woody species in agriculture, forestry and agroforestry. It outlines some of the important research needs for such systems and the role which isotopes could play in the research. (author)

  12. Nutrition and adventitious rooting in woody plants

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    Fernanda Bortolanza Pereira

    2016-09-01

    Full Text Available Vegetative propagation success of commercial genotypes via cutting techniques is related to several factors, including nutritional status of mother trees and of propagation material. The nutritional status determines the carbohydrate quantities, auxins and other compounds of plant essential metabolism for root initiation and development. Each nutrient has specific functions in plant, acting on plant structure or on plant physiology. Although the importance of mineral nutrition for success of woody plants vegetative propagation and its relation with adventitious rooting is recognized, the role of some mineral nutrients is still unknown. Due to biochemical and physiological complexity of adventitious rooting process, there are few researches to determine de role of nutrients on development of adventitious roots. This review intends to explore de state of the art about the effect of mineral nutrition on adventitious rooting of woody plants.

  13. [Regenerative morphological traits in a woody species community in Tumbesian tropical dry forest].

    Science.gov (United States)

    Romero-Saritama, José Miguel; Pérez-Rúuz, César

    2016-06-01

    The study of functional morphological traits enables us to know fundamental aspects of the dynamics of plant communities in local and global habitats. Regenerative morphological traits play an important role in defining plant history and ecological behavior. Seed and fruit characteristics determine to a large extent the patterns for dispersal, germination, establishment and seedling recruitment a given species exhibits on its natural habitat. Despite their prominent role, seed and fruit traits have been poorly studied at the community level of woody plant species in neo-tropical dry forests. In the present study we aimed at i) evaluate the functional role of morphological traits of seeds, fruits and embryo in woody plant species; ii) determine which are the morphological patterns present in seeds collected from the community of woody species that occur in neo-tropical dry forests; and iii) compare woody plant species seed mass values comparatively between neo-tropical dry and tropical forests. To do so, mature seeds were collected from 79 plant species that occur in the Tumbesian forest of Southwest Ecuador. The studied species included the 42 and 37 most representative tree and shrubbery species of the Tumbesian forest respectively. A total of 18 morphological traits (seven quantitative and 11 qualitative) were measured and evaluated in the seeds, fruits and embryos of the selected species, and we compared the seeds mass with other forest types. Our results showed a huge heterogeneity among traits values in the studied species. Seed mass, volume and number were the traits that vary the most at the community level, i.e. seed length ranged from 1.3 to 39 mm, and seed width from 0.6 to 25 mm. Only six embryo types were found among the 79 plant species. In 40 % of the cases, fully developed inverted embryos with large and thick cotyledons to store considerable amount of nutrients were recorded. We concluded that highly variable and functionally complementary

  14. Woody structure facilitates invasion of woody plants by providing perches for birds.

    Science.gov (United States)

    Prather, Chelse M; Huynh, Andrew; Pennings, Steven C

    2017-10-01

    Woody encroachment threatens prairie ecosystems globally, and thus understanding the mechanisms that facilitate woody encroachment is of critical importance. Coastal tallgrass prairies along the Gulf Coast of the US are currently threatened by the spread of several species of woody plants. We studied a coastal tallgrass prairie in Texas, USA, to determine if existing woody structure increased the supply of seeds from woody plants via dispersal by birds. Specifically, we determined if (i) more seedlings of an invasive tree ( Tridacia sebifera ) are present surrounding a native woody plant ( Myrica cerifera ); (ii) wooden perches increase the quantity of seeds dispersed to a grassland; and (iii) perches alter the composition of the seed rain seasonally in prairie habitats with differing amounts of native and invasive woody vegetation, both underneath and away from artificial wooden perches. More T. sebifera seedlings were found within M. cerifera patches than in graminoid-dominated areas. Although perches did not affect the total number of seeds, perches changed the composition of seed rain to be less dominated by grasses and forbs. Specifically, 20-30 times as many seeds of two invasive species of woody plants were found underneath perches independent of background vegetation, especially during months when seed rain was highest. These results suggest that existing woody structure in a grassland can promote further woody encroachment by enhancing seed dispersal by birds. This finding argues for management to reduce woody plant abundance before exotic plants set seeds and argues against the use of artificial perches as a restoration technique in grasslands threatened by woody species.

  15. Exotic woody plant invaders of the Transvaal

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    L. Henderson

    1984-12-01

    Full Text Available The frequency and abundance o ;f exotic, woody plant invaders were recorded in 60% of the quarter degree squares in the study area. Sixty-one invaders were encountered o f which the most important and aggressive were Acacia dealbaia, Populus spp.,  Melia azedarach, Opuntia ficus-indica, Salix babylonica and  Acacia mearnsii. Invasion patterns are discussed and an attempt is made to correlate distribution with environmental factors. Attention is drawn to the areas of greatest invasion and the areas that are liable to show the greatest expansion in the future.

  16. Quality maintenance Tropical Plants

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    Gláucia Moraes Dias

    2016-11-01

    Full Text Available The climatic characteristics of the country favor the cultivation of tropical flowers. The continued expansion of this market is due the beauty, exoticit nature and postharvest longevity of flower. However, little is known about the postharvest of tropical plants. Therefore, this paper provides information on harvest, handling and storage of cut tropical plantspostharvest, storage temperature, conditioning solution.

  17. The flora of woody plants and vegetation on the Horn of Africa

    DEFF Research Database (Denmark)

    Friis, Ib

    2017-01-01

    There are about one thousand species of woody plants that occur naturally on the Horn of Africa, including trees and large shrubs, and they have many functions in the highly varied ecosystem on the Horn, including soil conservation and the prevention of flooding during tropical rainstorms. For hi...

  18. Soil compaction and growth of woody plants

    Energy Technology Data Exchange (ETDEWEB)

    Kozlowski, T.T. [Univ. of California, Berkeley (United States). Dept. of Environmental Science, Policy and Management

    1999-07-01

    Although soil compaction in the field may benefit or inhibit the growth of plants, the harmful effects are much more common. This paper emphasizes the deleterious effects of predominantly high levels of soil compaction on plant growth and yield. High levels of soil compaction are common in heavily used recreation areas, construction sites, urban areas, timber harvesting sites, fruit orchards, agroforestry systems and tree nurseries. Compaction can occur naturally by settling or slumping of soil or may be induced by tillage tools, heavy machinery, pedestrian traffic, trampling by animals and fire. Compaction typically alters soil structure and hydrology by increasing soil bulk density; breaking down soil aggregates; decreasing soil porosity, aeration and infiltration capacity; and by increasing soil strength, water runoff and soil erosion. Appreciable compaction of soil leads to physiological dysfunctions in plants. Often, but not always, reduced water absorption and leaf water deficits develop. Soil compaction also induces changes in the amounts and balances of growth hormones in plants, especially increases in abscisic acid and ethylene. Absorption of the major mineral nutrients is reduced by compaction of both surface soils and subsoils. The rate of photosynthesis of plants growing in very compacted soil is decreased by both stomatal and non-stomatal inhibition. Total photosynthesis is reduced as a result of smaller leaf areas. As soils become increasingly compacted respiration of roots shifts toward an anaerobic state. Severe soil compaction adversely influences regeneration of forest stands by inhibiting seed germination and growth of seedlings, and by inducing seedling mortality. Growth of woody plants beyond the seedling stage and yields of harvestable plant products also are greatly decreased by soil compaction because of the combined effects of high soil strength, decreased infiltration of water and poor soil aeration, all of which lead to a decreased

  19. Soil compaction and growth of woody plants

    International Nuclear Information System (INIS)

    Kozlowski, T.T.

    1999-01-01

    Although soil compaction in the field may benefit or inhibit the growth of plants, the harmful effects are much more common. This paper emphasizes the deleterious effects of predominantly high levels of soil compaction on plant growth and yield. High levels of soil compaction are common in heavily used recreation areas, construction sites, urban areas, timber harvesting sites, fruit orchards, agroforestry systems and tree nurseries. Compaction can occur naturally by settling or slumping of soil or may be induced by tillage tools, heavy machinery, pedestrian traffic, trampling by animals and fire. Compaction typically alters soil structure and hydrology by increasing soil bulk density; breaking down soil aggregates; decreasing soil porosity, aeration and infiltration capacity; and by increasing soil strength, water runoff and soil erosion. Appreciable compaction of soil leads to physiological dysfunctions in plants. Often, but not always, reduced water absorption and leaf water deficits develop. Soil compaction also induces changes in the amounts and balances of growth hormones in plants, especially increases in abscisic acid and ethylene. Absorption of the major mineral nutrients is reduced by compaction of both surface soils and subsoils. The rate of photosynthesis of plants growing in very compacted soil is decreased by both stomatal and non-stomatal inhibition. Total photosynthesis is reduced as a result of smaller leaf areas. As soils become increasingly compacted respiration of roots shifts toward an anaerobic state. Severe soil compaction adversely influences regeneration of forest stands by inhibiting seed germination and growth of seedlings, and by inducing seedling mortality. Growth of woody plants beyond the seedling stage and yields of harvestable plant products also are greatly decreased by soil compaction because of the combined effects of high soil strength, decreased infiltration of water and poor soil aeration, all of which lead to a decreased

  20. Overcoming barriers to seedling regeneration during forest restoration on tropical pasture land and the potential value of woody weeds

    Directory of Open Access Journals (Sweden)

    Amelia eElgar

    2014-05-01

    Full Text Available Combating the legacy of deforestation on tropical biodiversity requires the conversion to forest of large areas of established pasture, where barriers to native plant regeneration include competition with pasture grasses and poor propagule supply (seed availability. In addition, initial woody plants that colonise pasture are often invasive non-native species whose ecological roles and management in the context of forest regeneration are contested. In a restoration experiment at two 0.64 ha sites we quantified the response of native woody vegetation recruitment to (1 release from competition with introduced pasture grasses, and (2 local facilitation of frugivore-assisted seed dispersal provided by scattered woody plants and artificial bird perches. Herbicide pasture grass suppression during 20 months caused a significant but modest increase in density of native woody seedlings, together with abundant co-recruitment of the prominent non-native pioneer wild tobacco (Solanum mauritianum. Recruitment of native species was further enhanced by local structure in herbicide-treated areas, being consistently greater under live trees and dead non-native shrubs (herbicide-treated than in open areas, and intermediate under bird perches. Native seedling recruitment comprised 28 species across 0.25 ha sampled but was dominated by two rainforest pioneers (Homalanthus novoguineensis, Polyscias murrayi. These early results are consistent with the expected increase in woody vegetation recruitment in response to release from competitive and dispersive barriers to rainforest regeneration. The findings highlight the need for a pragmatic consideration of the ecological roles of woody weeds and the potential roles of ‘new forests’ more broadly in accelerating succession of humid tropical forest across large areas of retired agricultural land.

  1. Strategies of two tropical woody species to tolerate salt stress

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    Bruno Melo Lustosa

    2017-03-01

    Full Text Available This study aimed to evaluate the leaf primary metabolism in two woody species, Sterculia foetida and Bombacopsis glabra. Both species have seeds rich in oil and they are largely found in regions with irregularities in water availability. Seedlings were grown in a greenhouse from seeds. At 140 days after emergence, 50% of the plants were subjected to salt stress for 23 days, daily receiving 100 mM of NaCl solution. In both species, leaf stomata conductance and water potential decreased quickly under salt stress. The two species showed different strategies in photosynthetic pigment concentration and components of nitrogen metabolism. S. foetida kept the pigment concentration unchanged after 23 days of stress, while B. glabra increased concentration of chlorophyll a and carotenoids. S. foetida showed a high leaf concentration of K+ in stressed plants and a Na+/K+ ratio without differences when compared to control. Thus, S. foetida presented a better ionic balance, while B. glabra invested in photoprotection. Therefore, both species present potential to be planted in Brazilian Northeast, where water deficit and salt stress are challenging for annual crops.

  2. Extreme low temperature tolerance in woody plants

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    George Richard Strimbeck

    2015-10-01

    Full Text Available Woody plants in boreal to arctic environments and high mountains survive prolonged exposure to temperatures below -40˚C and minimum temperatures below -60˚C, and laboratory tests show that many of these species can also survive immersion in liquid nitrogen at -196˚C. Studies of biochemical changes that occur during acclimation, including recent proteomic and metabolomic studies, have identified changes in carbohydrate and compatible solute concentrations, membrane lipid composition, and proteins, notably dehydrins, that may have important roles in survival at extreme low temperature. Consideration of the biophysical mechanisms of membrane stress and strain lead to the following hypotheses for cellular and molecular mechanisms of survival at extreme low temperature: 1. Changes in lipid composition stabilize membranes at temperatures above the lipid phase transition temperature (-20 to 30˚C, preventing phase changes that result in irreversible injury. 2. High concentrations of oligosaccharides promote vitrification or high viscosity in the cytoplasm in freeze-dehydrated cells, which would prevent deleterious interactions between membranes. 3. Dehydrins bind membranes and further promote vitrification or act stearically to prevent membrane-membrane interactions.

  3. Non-structural carbohydrates in woody plants compared among laboratories

    NARCIS (Netherlands)

    Quentin, Audrey G.; Pinkard, Elizabeth A.; Ryan, Michael G.; Tissue, David T.; Baggett, Scott L.; Adams, Henry D.; Maillard, Pascale; Marchand, Jacqueline; Landhäusser, Simon M.; Lacointe, André; Gibon, Yves; Anderegg, William R.L.; Asao, Shinichi; Atkin, Owen K.; Bonhomme, Marc; Claye, Caroline; Chow, Pak S.; Clément-Vidal, Anne; Davies, Noel W.; Dickman, Turin L.; Dumbur, Rita; Ellsworth, David S.; Falk, Kristen; Galiano, Lucía; Grünzweig, José M.; Hartmann, Henrik; Hoch, Günter; Hood, Sharon; Jones, Joanna E.; Koike, Takayoshi; Kuhlmann, Iris; Lloret, Francisco; Maestro, Melchor; Mansfield, Shawn D.; Martínez-Vilalta, Jordi; Maucourt, Mickael; McDowell, Nathan G.; Moing, Annick; Muller, Bertrand; Nebauer, Sergio G.; Niinemets, Ülo; Palacio, Sara; Piper, Frida; Raveh, Eran; Richter, Andreas; Rolland, Gaëlle; Rosas, Teresa; Joanis, Brigitte Saint; Sala, Anna; Smith, Renee A.; Sterck, Frank; Stinziano, Joseph R.; Tobias, Mari; Unda, Faride; Watanabe, Makoto; Way, Danielle A.; Weerasinghe, Lasantha K.; Wild, Birgit; Wiley, Erin; Woodruff, David R.

    2015-01-01

    Non-structural carbohydrates (NSC) in plant tissue are frequently quantified to make inferences about plant responses to environmental conditions. Laboratories publishing estimates of NSC of woody plants use many different methods to evaluate NSC. We asked whether NSC estimates in the recent

  4. Can lemmings control the expansion of woody plants on tundra?

    Science.gov (United States)

    Oksanen, Lauri; Oksanen, Tarja; Olofsson, Johan; Virtanen, Risto; Hoset, Katrine; Tuomi, Maria; Kyrö, Kukka

    2013-04-01

    The ongoing expansion of woody vegetation in the arctic, due to global warming, creates a positive feed back loop. Increasing abundance of woody plants reduces surface albedo both directly and via speeding up snow melt. Thus a successively greater fraction of incoming solar radiation is absorbed and converted to heat. Browsing mammals - both big and small - can prevent this by consuming woody plants. However, the grazer/browser community of many tundra areas is dominated by brown/Norwegian lemmings (Lemmus spp.) which eat graminoids and mosses and cannot use woody plants as forage. It would seem a priori likely that in such areas, mammalian herbivores speed up the expansion of woody plants by improving the chances of their seedlings to get established. We studied the impact of lemmings on woody plants by constructing lemming proof exclosures within piece high-altitude tundra at Joatkanjávri, northernmost Norway. The exclosures were constructed in 1998, during a period of low lemming densities, in snow-beds, where Norwegian lemmings (L. lemmus) were the only ecologically significant herbivorous mammals. (Reindeer migrate through the area in May, when snow-beds are inaccessible for them; during the fall migration, the area represents a dead end and is therefore avoided.) We chose pairs of maximally similar vegetation patches of 0.5 by 0.5 m and randomly assigned one of each pair to become an exclosure while the other plot was left open. The initial state of the vegetation was documented by the point frequency method. In 2008, after the 2007 lemming outbreak, the same documentation was repeated; thereafter the plots were harvested, the vegetation was sorted to species, oven dried and weighed. Exclusion of lemmings resulted to pronounced increase in community level plant biomass. Evergreen woody plants were especially favored by the exclusion of lemming: their above-ground biomass in exclosures was 14 times as great as their biomass on open reference plots. The

  5. Comparative study of phloem loading radiotracer techniques for in vivo sucrose translocation in non woody and woody plants

    International Nuclear Information System (INIS)

    Kulkarni, Pranav; Pandey, Manish; Suprasanna Penna; Ramteke, Sahadeo

    2017-01-01

    The application of radioisotopes for analysing the in vivo physiological responses in plants is a well known practical approach for the plant physiologists. Physiological difference in woody and non woody plants necessitates the need for universal way of application of radioisotopes to study in vivo sucrose translocation. In this study, grape vine (Vitis vinifera cv. Thomson seedless) and mustard (Brassica juncea cv. Pusa Bold) plants having active source and sink were used as representative system for woody and non woody plants. In present work we applied different strategies for radio activity loading in both boody and non woody plant viz. phloem loading via cut end, direct injection into phloem and activity incorporation through minor vein of leaves (gaseous CO 2 incorporation)

  6. Determination of native woody landscape plants in Bursa and Uludag

    African Journals Online (AJOL)

    Around Bursa and Uludag is a wide range of native woody plants of which are commonly used for landscape planning. The present study pointed out a total of 72 plant species, consisting of 36 trees, 32 shrubs, 7 treelets and 4 climber groups, around the region which are notified to be suitable for rural and urban planning ...

  7. Leaf structural traits of tropical woody species resistant to cement dust.

    Science.gov (United States)

    Siqueira-Silva, Advanio Inácio; Pereira, Eduardo Gusmão; Modolo, Luzia Valentina; Paiva, Elder Antonio Sousa

    2016-08-01

    Cement industries located nearby limestone outcrops in Brazil have contributed to the coating of cement dust over native plant species. However, little is known about the extent of the response of tropical woody plants to such environmental pollutant particularly during the first stages of plant development and establishment. This work focused on the investigation of possible alterations in leaf structural and ultrastructural traits of 5-month-old Guazuma ulmifolia Lam. (Malvaceae), 6-month-old Myracrodruon urundeuva Allemão (Anacardiaceae), and 9-month-old Trichilia hirta L. (Meliaceae) challenged superficially with cement dust during new leaf development. Leaf surface of plants, the soil or both (leaf plus soil), were treated (or not) for 60 days, under controlled conditions, with cement dust at 2.5 or 5.0 mg cm(-2). After exposure, no significant structural changes were observed in plant leaves. Also, no plant death was recorded by the end of the experiment. There was also some evidence of localized leaf necrosis in G. ulmifolia and T. hirta, leaf curling in M. urundeuva and T. hirta, and bulges formation on epidermal surface of T. hirta, after cement dust contact with plant shoots. All species studied exhibited stomata obliteration while T. hirta, in particular, presented early leaf abscission, changes in cellular relief, and organization and content of midrib cells. No significant ultrastructural alterations were detected under the experimental conditions studied. Indeed, mesophyll cells presented plastids with intact membrane systems. The high plant survival rates, together with mild morphoanatomic traits alterations in leaves, indicate that G. ulmifolia is more resistant to cement dust pollutant, followed by M. urundeuva and T. hirta. Thus, the three plant species are promising for being used to revegetate areas impacted by cement industries activities.

  8. Coarse woody debris carbon storage across a mean annual temperature gradient in tropical montane wet forest

    Science.gov (United States)

    Darcey K. Iwashita; Creighton M. Litton; Christian P. Giardina

    2013-01-01

    Coarse woody debris (CWD; defined here as fallen and standing dead trees and tree ferns) is a critical structural and functional component of forest ecosystems that typically comprises a large proportion of total aboveground carbon (C) storage. However, CWD estimates for the tropics are uncommon, and little is known about how C storage in CWD will respond to climate...

  9. Peculiarities of the Woody Plants Re-Bloom

    OpenAIRE

    Opalko Olga Anatolievna; Opalko Anatoly Ivanovich

    2015-01-01

    The data of literary sources concerning the bloom of angiosperm plants and deviation in the development of a flower and inflorescence, in particular untimely flowering, was generalized; our observation results of some peculiarities of re-bloom of woody plants in the National Dendrological Park “Sofiyivka” of NAS of Ukraine (NDP “Sofiyivka”) were discussed. The flowering process was formed during a long-term evolution of a propagation system of angiosperm plants as a basis of fertilization and...

  10. A century of woody plant encroachment in the dry Kimberley ...

    African Journals Online (AJOL)

    We used aerial and fixed-point repeat ground photographs, including historical photographs taken at the time of the Second Anglo-Boer War of 1899–1902, to assess the scale and timing of woody plant encroachment in the dry savannas near Kimberley in South Africa (mean annual rainfall = 300–400 mm). There were ...

  11. Comparative Analysis of Woody Plants Biomass on the Affected

    African Journals Online (AJOL)

    Nwokem et al.

    stands that were generated from the field using sample quadrats and measuring ... woody plants on the affected and restricted land management practices. F u ll L en .... divided into 6 strata that served as a guide to locate the quadrat samples.

  12. Measuring Biomass and Carbon Stock in Resprouting Woody Plants

    Science.gov (United States)

    Matula, Radim; Damborská, Lenka; Nečasová, Monika; Geršl, Milan; Šrámek, Martin

    2015-01-01

    Resprouting multi-stemmed woody plants form an important component of the woody vegetation in many ecosystems, but a clear methodology for reliable measurement of their size and quick, non-destructive estimation of their woody biomass and carbon stock is lacking. Our goal was to find a minimum number of sprouts, i.e., the most easily obtainable, and sprout parameters that should be measured for accurate sprout biomass and carbon stock estimates. Using data for 5 common temperate woody species, we modelled carbon stock and sprout biomass as a function of an increasing number of sprouts in an interaction with different sprout parameters. The mean basal diameter of only two to five of the thickest sprouts and the basal diameter and DBH of the thickest sprouts per stump proved to be accurate estimators for the total sprout biomass of the individual resprouters and the populations of resprouters, respectively. Carbon stock estimates were strongly correlated with biomass estimates, but relative carbon content varied among species. Our study demonstrated that the size of the resprouters can be easily measured, and their biomass and carbon stock estimated; therefore, resprouters can be simply incorporated into studies of woody vegetation. PMID:25719601

  13. Ozone injury to some Japanese woody plant species in summer

    Energy Technology Data Exchange (ETDEWEB)

    Kadota, M; Ohta, K

    1972-01-01

    Ozone is an important constituent of photochemical oxidant smog. This paper reveals the semiquantitative responses of various Japanese woody plant species to ozone (0.25 ppm). Plant species examined in this investigation include four coniferous trees, eleven evergreen broad-leaf trees, and twenty-one deciduous broad-leaf trees or shrubs. Generally, plants having thin leaves were susceptible. The plant species with higher activity of photosynthesis appeared to be more susceptible. As a whole, evergreen broad-leaf trees could be said to be more resistant to ozone than deciduous broad-leaf trees.

  14. Tropical Plant Collections

    DEFF Research Database (Denmark)

    Friis, Ib; Balslev, Henrik

    that involved Germany, Britain and France, until independence, which was brightened by exemplary collaboration. Muasya focussed on South Africa, which is the most developed country in sub-Saharan Africa with a well-functioning network of herbaria that covers widely different biota. Sanjappa outlined the history...... crisis. Friis gave a broad overview of the history of herbaria and botanical gardens and the changing conceptual frameworks behind their existence. Baldini talked about early Italian botanical collectors and the fate of their collections. Baas accounted for the Golden Age of Dutch botany during pre......-colonial and early colonial periods. With the presentation by Cribb on the botany of the British Empire we were fully into the colonial period, focussing on the Royal Botanic Gardens at Kew. The situation in North America was treated by Funk, who illustrated the development of collections of tropical plants...

  15. Leaf surface anatomy in some woody plants from northeastern Mexico

    International Nuclear Information System (INIS)

    Maiti, R.; Rodriguez, H.G.; Balboa, P.C.R.; Kumari, A

    2016-01-01

    Studies on leaf surface anatomy of woody plants and its significance are rare. The present study was undertaken in the Forest Science Faculty Experimental Research Station, UANL, Mexico, with objectives to determine the variability in leaf surface anatomy in the woody plants of the Tamaulipan thornscrub and its utility in taxonomy and possible adaptation to the prevailing semiarid conditions. The results show the presence of large variability in several leaf anatomical traits viz., waxy leaf surface, type of stomata, its size, and distribution. The species have been classified on the basis of various traits which can be used in species delimitation and adaptation to the semiarid condition such as waxy leaf surface, absence sparse stomata on the leaf surface, sunken stomata. The species identified as better adapters to semi-arid environments on the basis of the presence and absence of stomata on both adaxial and abaxial surface viz., Eysenhardtia texana, Parkinsonia texana, Gymnosperma glutinosum, Celtis laevigata, Condalia hookeri and Karwinskia humboldtiana. (author)

  16. Invasive alien woody plants of the northern Cape

    Directory of Open Access Journals (Sweden)

    L. Henderson

    1991-10-01

    Full Text Available The frequency and abundance of invasive alien woody plants were recorded along roadsides and at watercourse crossings in 31% (90/286 of the quarter degree squares in the study area. The survey yielded 23 species of which the most prominent invaders were Prosopis spp. The most prominent remaining species were: Opuntia ficus-indica, Nicotiana glauca and Melia azedarach. The greatest abundance and diversity of alien invader plants were recorded near human settlements. More than half of the total recorded species have invaded perennial riverbanks. The episodic Molopo and Kuruman Rivers have been invaded almost exclusively by  Prosopis spp., which in places have formed extensive stands.

  17. Spatial vegetation patterns and neighborhood competition among woody plants in an East African savanna.

    Science.gov (United States)

    Dohn, Justin; Augustine, David J; Hanan, Niall P; Ratnam, Jayashree; Sankaran, Mahesh

    2017-02-01

    The majority of research on savanna vegetation dynamics has focused on the coexistence of woody and herbaceous vegetation. Interactions among woody plants in savannas are relatively poorly understood. We present data from a 10-yr longitudinal study of spatially explicit growth patterns of woody vegetation in an East African savanna following exclusion of large herbivores and in the absence of fire. We examined plant spatial patterns and quantified the degree of competition among woody individuals. Woody plants in this semiarid savanna exhibit strongly clumped spatial distributions at scales of 1-5 m. However, analysis of woody plant growth rates relative to their conspecific and heterospecific neighbors revealed evidence for strong competitive interactions at neighborhood scales of up to 5 m for most woody plant species. Thus, woody plants were aggregated in clumps despite significantly decreased growth rates in close proximity to neighbors, indicating that the spatial distribution of woody plants in this region depends on dispersal and establishment processes rather than on competitive, density-dependent mortality. However, our documentation of suppressive effects of woody plants on neighbors also suggests a potentially important role for tree-tree competition in controlling vegetation structure and indicates that the balanced-competition hypothesis may contribute to well-known patterns in maximum tree cover across rainfall gradients in Africa. © 2016 by the Ecological Society of America.

  18. Forest structure and downed woody debris in boreal, temperate, and tropical forest fragments.

    Science.gov (United States)

    Gould, William A; González, Grizelle; Hudak, Andrew T; Hollingsworth, Teresa Nettleton; Hollingsworth, Jamie

    2008-12-01

    Forest fragmentation affects the heterogeneity of accumulated fuels by increasing the diversity of forest types and by increasing forest edges. This heterogeneity has implications in how we manage fuels, fire, and forests. Understanding the relative importance of fragmentation on woody biomass within a single climatic regime, and along climatic gradients, will improve our ability to manage forest fuels and predict fire behavior. In this study we assessed forest fuel characteristics in stands of differing moisture, i.e., dry and moist forests, structure, i.e., open canopy (typically younger) vs. closed canopy (typically older) stands, and size, i.e., small (10-14 ha), medium (33 to 60 ha), and large (100-240 ha) along a climatic gradient of boreal, temperate, and tropical forests. We measured duff, litter, fine and coarse woody debris, standing dead, and live biomass in a series of plots along a transect from outside the forest edge to the fragment interior. The goal was to determine how forest structure and fuel characteristics varied along this transect and whether this variation differed with temperature, moisture, structure, and fragment size. We found nonlinear relationships of coarse woody debris, fine woody debris, standing dead and live tree biomass with mean annual median temperature. Biomass for these variables was greatest in temperate sites. Forest floor fuels (duff and litter) had a linear relationship with temperature and biomass was greatest in boreal sites. In a five-way multivariate analysis of variance we found that temperature, moisture, and age/structure had significant effects on forest floor fuels, downed woody debris, and live tree biomass. Fragment size had an effect on forest floor fuels and live tree biomass. Distance from forest edge had significant effects for only a few subgroups sampled. With some exceptions edges were not distinguishable from interiors in terms of fuels.

  19. Spatiotemporal soil and saprolite moisture dynamics across a semi-arid woody plant gradient

    Science.gov (United States)

    Woody plant cover has increased 10-fold over the last 140+ years in many parts of the semi-arid western USA. Woody plant cover can alter the timing and amount of plant available moisture in the soil and saprolite. To assess spatiotemporal subsurface moisture dynamics over two water years in a snow-d...

  20. Peculiarities of the Woody Plants Re-Bloom

    Directory of Open Access Journals (Sweden)

    Opalko Olga Anatolievna

    2015-09-01

    Full Text Available The data of literary sources concerning the bloom of angiosperm plants and deviation in the development of a flower and inflorescence, in particular untimely flowering, was generalized; our observation results of some peculiarities of re-bloom of woody plants in the National Dendrological Park “Sofiyivka” of NAS of Ukraine (NDP “Sofiyivka” were discussed. The flowering process was formed during a long-term evolution of a propagation system of angiosperm plants as a basis of fertilization and further fruit and seed development. As a result of vernalization and photoperiodism reactions, flowering (under regular conditions occurs in the most favorable period for pollination and fertilization of every plant. However, various deviations, in particular, the untimely (most frequently double, sometimes three- and four-fold flowering occurs in this perfect process of generative organ formation of angiosperm plants. An increased number of reports about re-bloom (at the end of summer – at the beginning of fall of the representatives of various woody plant species whose flowers usually blossom in May-June prompts the analysis of the available information concerning the mechanisms of flowering and the causes which lead to deviation of flowering processes. Flowering of the woody plant representatives of the collection fund of the NDP “Sofiyivka” was studied; statistics about re-bloom in different cities of Ukraine were monitored. The classification of re-bloom facts was carried out according to V.L. Vitkovskiy (1984. Although this classification has mostly a stated nature, it was good enough when being formulated and, with certain conditions, it can be applied nowadays. Accordingly, using this classification, abnormal cases can include facts of early summer-fall flowering and early winter flowering. A late spring flowering can be adaptive response of damaged plants to exogenous stresses, due to which the probability of sexual propagation remains

  1. BAAD: a Biomass And Allometry Database for woody plants

    Energy Technology Data Exchange (ETDEWEB)

    Falster, Daniel; Duursma, Remko; Ishihara, Masae; Barneche, Diego; Fitzjohn, Richard; Varhammar, Angelica; Aiba, Masahiro; Ando, M.; Anten, Niels; Aspinwall, Michael J.; Baltzer, Jennifer; Baraloto, Christopher; Battaglia, Michael; Battles, John; Bond-Lamberty, Benjamin; van Breugel, Michiel; Camac, James; Claveau, Yves; Coll Mir, Llus; Dannoura, Dannoura; Delagrange, Sylvain; Domec, Jean-Cristophe; Fatemi, Farrah; Feng, Wang; Gargaglione, Veronica; Goto, Yoshiaki; Hagihara, Akio; Hall, Jefferson S.; Hamilton, Steve; Harja, Degi; Hiura, Tsutom; Holdaway, Robert; Hutley, L. B.; Ichie, Tomoaki; Jokela, Eric; Kantola, Anu; Kelly, Jeffery W.; Kenzo, Tanaka; King, David A.; Kloeppel, Brian; Kohyama, Takashi; Komiyama, Akira; Laclau, Jean-Paul; Lusk, Christopher; Maguire, Doug; le Maire, Guerric; Makela, Annikki; Markesteijn, Lars; Marshall, John; McCulloh, Kate; Miyata, Itsuo; Mokany, Karen; Mori, Shigeta; Myster, Randall; Nagano, Masahiro; Naidu, Shawna; Nouvellon, Yann; O' Grady, Anthony; O' Hara, Kevin; Ohtsuka, Toshiyuki; Osada, Noriyuki; Osunkoya, Olusegun O.; Luis Peri, Pablo; Petritan, Mary; Poorter, Lourens; Portsmuth, Angelika; Potvin, Catherine; Ransijn, Johannes; Reid, Douglas; Ribeiro, Sabina C.; Roberts, Scott; Rodriguez, Rolando; Saldana-Acosta, Angela; Santa-Regina, Ignacio; Sasa, Kaichiro; Gailia Selaya, Nadezhda; Sillett, Stephen; Sterck, Frank; Takagi, Kentaro; Tange, Takeshi; Tanouchi, Hiroyuki; Tissue, David; Umehara, Tohru; Utsugi, Hajime; Vadeboncoeur, Matthew; Valladares, Fernando; Vanninen, Petteri; Wang, Jian; Wenk, Elizabeth; Williams, Dick; Ximenes, Fabiano de Aquino; Yamaba, Atsushi; Yamada, Toshihiro; Yamakura, Takuo; Yanai, Ruth; York, Robert

    2015-05-07

    Quantifying the amount of mass or energy invested in plant tissues is of fundamental interest across a range of disciplines, including ecology, forestry, ecosystem science, and climate change science (Niklas, 1994; Chave et al. 2005; Falster et al. 2011). The allocation of net primary production into different plant components is an important process affecting the lifetime of carbon in ecosystems, and resource use and productivity by plants (Cannell & Dewar, 1994; Litton et al. 2007; Poorter et al. 2012). While many studies in have destructively harvested woody plants in the name of science, most of these data have only been made available in the form of summary tables or figures included in publications. Until now, the raw data has resided piecemeal on the hard drives of individual scientists spread around the world. Several studies have gathered together the fitted (allometric) equations for separate datasets (Ter-Mikaelian & Korzukhin, 1997; Jenkins et al. 2003; Zianis et al. 2005; Henry et al. 2013), but none have previously attempted to organize and share the raw individual plant data underpinning these equations on a large scale. Gathered together, such data would represent an important resource for the community, meeting a widely recognised need for rich, open data resources to solve ecological problems (Costello et al. 2013; Fady et al. 2014; Harfoot & Roberts, 2014; Costello et al. 2013). We (D.S. Falster and R.A. Duursma, with the help of D.R. Barneche, R.G. FitzJohn and A. Vårhammar) set out to create such a resource, by asking authors directly whether they would be willing to make their raw data files freely available. The response was overwhelming: nearly everyone we contacted was interested to contribute their raw data. Moreover, we were invited to incorporate another compilation led by M. Ishihara and focussing on Japanese literature. As a result, we present BAAD: a Biomass And Allometry Database for woody plants, comprising data collected in 174

  2. Methods for Rapid Screening in Woody Plant Herbicide Development

    Directory of Open Access Journals (Sweden)

    William Stanley

    2014-07-01

    Full Text Available Methods for woody plant herbicide screening were assayed with the goal of reducing resources and time required to conduct preliminary screenings for new products. Rapid screening methods tested included greenhouse seedling screening, germinal screening, and seed screening. Triclopyr and eight experimental herbicides from Dow AgroSciences (DAS 313, 402, 534, 548, 602, 729, 779, and 896 were tested on black locust, loblolly pine, red maple, sweetgum, and water oak. Screening results detected differences in herbicide and species in all experiments in much less time (days to weeks than traditional field screenings and consumed significantly less resources (<500 mg acid equivalent per herbicide per screening. Using regression analysis, various rapid screening methods were linked into a system capable of rapidly and inexpensively assessing herbicide efficacy and spectrum of activity. Implementation of such a system could streamline early-stage herbicide development leading to field trials, potentially freeing resources for use in development of beneficial new herbicide products.

  3. Invasive alien woody plants of the Orange Free State

    Directory of Open Access Journals (Sweden)

    L. Henderson

    1991-09-01

    Full Text Available The frequency and abundance of invasive alien woody plants were recorded along roadsides and at watercourse crossings in 66% (151/230 of the quarter degree squares in the study area. The survey yielded 64 species of which the most prominent (in order of prominence in streambank habitats were:  Salix babylonica, Populus x  canescens, Acacia dealbata and  Salix fragilis (fide R.D. Meikle pers. comm . The most prominent species (in order of prominence in roadside and veld habitats were:  Opunlia ficus-indica, Prunus persica, Eucalyptus spp..  Rosa eglanteria, Pyracantha angustifolia and Acacia dealbata.Little invasion was recorded for most of the province. The greatest intensity of invasion was recorded along the perennial rivers and rocky hillsides in the moist grassland of the eastern mountain region bordering on Lesotho and Natal.

  4. Woody debris

    Science.gov (United States)

    Donna B. Scheungrab; Carl C. Trettin; Russ Lea; Martin F. Jurgensen

    2000-01-01

    Woody debris can be defined as any dead, woody plant material, including logs, branches, standing dead trees, and root wads. Woody debris is an important part of forest and stream ecosystems because it has a role in carbon budgets and nutrient cycling, is a source of energy for aquatic ecosystems, provides habitat for terrestrial and aquatic organisms, and contributes...

  5. On the effects attendant on the decrease of the radionuclide contents in woody plants

    International Nuclear Information System (INIS)

    Bulko, N.I.; Shabaleva, M.A.; Starovojtova, T.V.

    2002-01-01

    Our experiment on the study of migration and accumulation of radiocesium in woody plants performed on radiation-contaminated forest soils within the greenhouse experiment/microfield experiment/natural forest stand system shows that it is quite possible to influence markedly on the Cs 137 migration within the soil/woody plant system by the purposeful action on water and nutritive regimes of bogs. When fertilizers are applied, a decrease in the Cs 137 contents in woody plants and an increase in growth indices are observed, these being attended with antagonism, dissolution, binding and maximization effects

  6. Seed production of woody plants in conditions of environment pollution by metallurgical industry emissions

    Directory of Open Access Journals (Sweden)

    Z. V. Gritzay

    2011-10-01

    Full Text Available The influence of environment pollution by metallurgical industry emissions on woody plants bearing parameters was examined. The results obtained show the decrease of bearing rate, diminution of seeds, fruits and seed cells sizes in woody plants affected by technogenic emissions. Attenuation of the 1000 seeds’ weight was established. Incresing the amount of fruits with development deviations was ascertained. It was found aplasia and abnormal form of the samara fruit of ash and ailanthus trees, arcuation and narrowing of some parts of the catalpa fruitcases. Practical recommendations on using seeds’ sensitive parameters in biomonitoring of woody phytocenoses under technogenic stressful conditions are proposed.

  7. Conundrums in mixed woody-herbaceous plant systems

    CSIR Research Space (South Africa)

    House, JI

    2003-11-01

    Full Text Available -form communities, the novel, complex, nonlinear behaviour of mixed tree-grass systems cannot be accounted for by simply studying or modelling woody and herbaceous components independently. A more robust understanding requires addressing three fundamental conundrums...

  8. 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.

  9. Effects of moisture content on coarse woody debris respiration in a tropical rainforest of Brunei Darussalam

    Science.gov (United States)

    Roh, Y.; Li, G.; Han, S. H.; Abu Salim, K.; Son, Y.

    2017-12-01

    Since coarse woody debris (CWD) respiration (Rcwd) has an important role in carbon (C) cycling in forest ecosystems, it is a significant parameter in an investigation of CWD decomposition rate. Rcwd is known as to be influenced not only by environmental factors but also by CWD properties (e.g., moisture content). This study investigated the effects of CWD moisture content on Rcwd in a lowland mixed Dipterocarp tropical rainforest of Brunei Darussalam. CWDs in the forest were selected and categorized into two decay classes (sound and partially decomposed), and three diameter classes (10-20 cm, 20-30 cm, more than 30 cm). Samplings of CWDs were conducted in February and October, 2016. The fresh weight and Rcwd of the samples were measured within 24 h of sampling. Rcwd measurements were conducted using a closed chamber system with a diffusion-type, non-dispersive infrared (NDIR) sensor. In February, the fresh weight and Rcwd of the samples were remeasured, after submerging them in the fresh water for 24, 48, and 72 h. The Rcwd increased significantly with moisture content in February (r2=0.25, p0.05). Rcwd was lowest in the largest diameter class (p0.05). On the basis of these results, the Rcwd in this site was in the range of Rcwd in previous studies conducted in other tropical rainforests. Rcwd increased with moisture content, however, the contribution of moisture content to changes in Rcwd might not be influential during the eight months study period.*Supported by research grants from the Korea Forest Service (2017044B10-1719-BB01).

  10. Effects of high-frequency understorey fires on woody plant regeneration in southeastern Amazonian forests

    Science.gov (United States)

    Balch, Jennifer K.; Massad, Tara J.; Brando, Paulo M.; Nepstad, Daniel C.; Curran, Lisa M.

    2013-01-01

    Anthropogenic understorey fires affect large areas of tropical forest, yet their effects on woody plant regeneration post-fire remain poorly understood. We examined the effects of repeated experimental fires on woody stem (less than 1 cm at base) mortality, recruitment, species diversity, community similarity and regeneration mode (seed versus sprout) in Mato Grosso, Brazil. From 2004 to 2010, forest plots (50 ha) were burned twice (B2) or five times (B5), and compared with an unburned control (B0). Stem density recovered within a year after the first burn (initial density: 12.4–13.2 stems m−2), but after 6 years, increased mortality and decreased regeneration—primarily of seedlings—led to a 63 per cent and 85 per cent reduction in stem density in B2 and B5, respectively. Seedlings and sprouts across plots in 2010 displayed remarkable community similarity owing to shared abundant species. Although the dominant surviving species were similar across plots, a major increase in sprouting occurred—almost three- and fourfold greater in B2 and B5 than in B0. In B5, 29 species disappeared and were replaced by 11 new species often present along fragmented forest edges. By 2010, the annual burn regime created substantial divergence between the seedling community and the initial adult tree community (greater than or equal to 20 cm dbh). Increased droughts and continued anthropogenic ignitions associated with frontier land uses may promote high-frequency fire regimes that may substantially alter regeneration and therefore successional processes. PMID:23610167

  11. Timing and abundance of flowering and fruiting of woody plants in the Hørsholm Arboretum

    DEFF Research Database (Denmark)

    Leverenz, Jerry

    The Arboretum in Hørsholm has an extensive collection of woody plant species of known origin. There are approximately 2200 woody plant taxa in the collection, representing 295 genera and 101 plant families. This collection is used to study how plants from different parts of the world thrive...... flowers (pollen) and fruit (seed) in order to have a clearer understanding of the negative results. As a first step we have begun to record if, and when, the taxa in the collection produce flowers (and thus pollen), and fruits (and thereby seed). In this Working Paper we present and analyse the results...

  12. Woody plant encroachment of grasslands: a comparison of terrestrial and wetland settings.

    Science.gov (United States)

    Saintilan, Neil; Rogers, Kerrylee

    2015-02-01

    A global trend of woody plant encroachment of terrestrial grasslands is co-incident with woody plant encroachment of wetland in freshwater and saline intertidal settings. There are several arguments for considering tree encroachment of wetlands in the context of woody shrub encroachment of grassland biomes. In both cases, delimitation of woody shrubs at regional scales is set by temperature thresholds for poleward extent, and by aridity within temperature limits. Latitudinal expansion has been observed for terrestrial woody shrubs and mangroves, following recent warming, but most expansion and thickening has been due to the occupation of previously water-limited grassland/saltmarsh environments. Increases in atmospheric CO₂, may facilitate the recruitment of trees in terrestrial and wetland settings. Improved water relations, a mechanism that would predict higher soil moisture in grasslands and saltmarshes, and also an enhanced capacity to survive arid conditions, reinforces local mechanisms of change. The expansion of woody shrubs and mangroves provides a negative feedback on elevated atmospheric CO₂ by increasing carbon sequestration in grassland and saltmarsh, and is a significant carbon sink globally. These broad-scale vegetation shifts may represent a new stable state, reinforced by positive feedbacks between global change drivers and endogenic mechanisms of persistence in the landscape.

  13. Do seedling functional groups reflect ecological strategies of woody plant species in Caatinga?

    Directory of Open Access Journals (Sweden)

    Tatiane Gomes Calaça Menezes

    2017-11-01

    Full Text Available ABSTRACT It is assumed that morphological traits of seedlings reflect different strategies in response to environmental conditions. The ecological significance of this has been widely documented in rainforests, where habitat structure and species interactions play an important role in community assembly. However, in seasonally dry ecosystems, where environmental filtering is expected to strongly influence community structure, this relationship is poorly understood. We investigated this relationship between functional groups of seedlings and life history traits and tested whether functional group predicts the ecological strategies employed by woody species to deal with the stressful conditions in seasonally dry ecosystems. Seedling functional groups, life history traits and traits that reflect ecological strategies for occupying seasonally dry environments were described for twenty-six plant species. Seedlings of species from the Caatinga vegetation exhibited a functional profile different from that observed in rainforests ecosystems. Phanerocotylar-epigeal seedlings were the most frequently observed groups, and had the largest range of ecological strategies related to dealing with seasonally dry environments, while phanerocotylar-hypogeal-reserve seedlings exhibited an increase in frequency with seasonality. We discuss these results in relation to those observed in other tropical forests and their ecological significance in seasonally dry environments.

  14. The contribution of woody plant materials on the several conditions in a space environment

    Science.gov (United States)

    Tomita-Yokotani, Kaori; Baba, Keiichi; Suzuki, Toshisada; Kimura, Shunta; Sato, Seigo; Katoh, Hiroshi; Abe, Yusuke; Katayama, Takeshi

    Woody plant materials have several utilization elements in our habitation environment on earth. The studies of woody plants under a space-environment in the vegetable kingdom have a high contribution to the study of various and exotic environmental responses, too. Woody plants can produce an excess oxygen, woody materials for the living cabin, and provide a biomass by cultivating crops and other species of creatures. Tree material would become to be a tool in closed bio-ecosystems such as an environment in a space. We named the trees used as material for the experiment related to space environments “CosmoBon”, small tree bonsai. Japanese cherry tree, “Sakura”, is famous and lovely tree in Japan. One species of “Sakura”, “Mamezakura, Prunus incisa”, is not only lovely tree species, but also suitable tree for the model tree of our purpose. The species of Prunus incisa is originally grown in volcano environment. That species of Sakura is originally grown on Mt. Fuji aria, oligotrophic place. We will try to build the best utilization usage of woody plant under the space environment by “Mamezakura” as a model tree. Here, we will show the importance of uniformity of materials when we will use the tree materials in a space environment. We will also discuss that tree has a high possibility of utilization under the space environments by using our several results related to this research.

  15. From Nehemiah Grew to Genomics: the emerging field of evo-devo research for woody plants

    Science.gov (United States)

    Andrew Groover; Quentin Cronk

    2013-01-01

    Wood has played a primary role in the evolution of land plants (Spicer and Groover 2010), but our understanding of the genes and mechanisms underlying wood evolution and development has been limited until recently. Importantly, many of the fundamental questions of woody plant evolution and development are now tractable using genomics and high-capacity sequencing...

  16. Immigrant phytophagous insects on woody plants in the United States and Canada: an annotated list.

    Science.gov (United States)

    William J. Mattson; P. Niemela; I. Millers; Y. Inguanzo

    1994-01-01

    Nearly 2,000 foreign plants and 2,000 foreign insect species have become naturalized in North America during the past 500 years. This publication documents those immigrant phytophagous insect species which have become established on woody plants or their products in the continental United States and Canada. Of these 368 immigrant insects, 72% came from Europe.

  17. Effects of alien woody plant invasion on the birds of Mountain ...

    African Journals Online (AJOL)

    The density, biomass, species richness and composition of birds in plots in two Mountain Fynbos plant-species assemblages (Tall Mixed Fynbos and Restionaceous Tussock Marsh), infested with alien woody plants (mainly Australian Acacia spp.) at the Cape of Good Hope Nature Reserve, South Africa, were compared ...

  18. Woody plants and the prediction of climate-change impacts on bird diversity

    DEFF Research Database (Denmark)

    Kissling, W. Daniel; Field, R.; Korntheuer, H.

    2010-01-01

    Current methods of assessing climate-induced shifts of species distributions rarely account for species interactions and usually ignore potential differences in response times of interacting taxa to climate change. Here, we used species-richness data from 1005 breeding bird and 1417 woody plant...... species in Kenya and employed model-averaged coefficients from regression models and median climatic forecasts assembled across 15 climate-change scenarios to predict bird species richness under climate change. Forecasts assuming an instantaneous response of woody plants and birds to climate change...... suggested increases in future bird species richness across most of Kenya whereas forecasts assuming strongly lagged woody plant responses to climate change indicated a reversed trend, i.e. reduced bird species richness. Uncertainties in predictions of future bird species richness were geographically...

  19. Environmental determinants of woody plant diversity at a regional scale in China.

    Directory of Open Access Journals (Sweden)

    Hong Qian

    Full Text Available Understanding what drives the geographic variation of species richness across the globe is a fundamental goal of ecology and biogeography. Environmental variables have been considered as drivers of global diversity patterns but there is no consensus among ecologists on what environmental variables are primary drivers of the geographic variation of species richness. Here, I examine the relationship of woody plant species richness at a regional scale in China with sixteen environmental variables representing energy availability, water availability, energy-water balance, seasonality, and habitat heterogeneity. I found that temperature seasonality is the best predictor of woody species richness in China. Other important environmental variables include annual precipitation, mean temperature of the coldest month, and potential evapotranspiration. The best model explains 85% of the variation in woody plant species richness at the regional scale in China.

  20. Comparisons of invasive plants in southern Africa originating from southern temperate, northern temperate and tropical regions

    Directory of Open Access Journals (Sweden)

    L. Henderson

    2006-08-01

    Full Text Available A subset of invasive alien plant species in southern Africa was analysed in terms of their history of introduction, rate of spread, countries/region of origin, taxonomy, growth forms, cultivated uses, weed status and current distribution in southern Africa, and comparisons made of those originating from south of the tropic of Capricorn, north of the tropic of Cancer and from the tropics. The subset of 233 species, belonging to 58 families, includes all important declared species and some potentially important species. Almost as many species originate from temperate regions (112 as from the tropics (121. Most southern temperate species came from Australia (28/36, most tropical species from tropical America (92/121 and most northern temperate species from Europe (including the Mediterranean and Asia (58/76. Transformers account for 33% of  all species. More transformers are of tropical origin (36 than of northern temperate (24 and southern temperate origin (18. However. 50% of southern temperate species are transformers, compared to 32% of northern temperate and 29% of tropical species. Southern temperate transformer species are mainly woody trees and shrubs that were established on a grand scale as silvicultural crops, barriers (hedges, windbreaks and screens and cover/binders. Most aquatics, herbs, climbers and succulent shrubs an. trom the tropics. Ornamentals are the single largest category of plants from all three regions, the tropics having contributed twice as many species as temperate regions.

  1. Mapping gains and losses in woody vegetation across global tropical drylands

    DEFF Research Database (Denmark)

    Tian, Feng; Brandt, Martin Stefan; Liu, Yi Y

    2017-01-01

    MODerate resolution Imaging Spectroradiometer (MODIS) Normalized Difference Vegetation Index (NDVI) data to remove the interannual fluctuations of the woody leaf component. We revealed significant trends (P ... trend in the leaf component (VODleaf modeled from NDVI), indicating pronounced gradual growth/decline in woody vegetation not captured by traditional assessments. The method is validated using a unique record of ground measurements from the semiarid Sahel and shows a strong agreement between changes...

  2. Functional network analysis of genes differentially expressed during xylogenesis in soc1ful woody Arabidopsis plants.

    Science.gov (United States)

    Davin, Nicolas; Edger, Patrick P; Hefer, Charles A; Mizrachi, Eshchar; Schuetz, Mathias; Smets, Erik; Myburg, Alexander A; Douglas, Carl J; Schranz, Michael E; Lens, Frederic

    2016-06-01

    Many plant genes are known to be involved in the development of cambium and wood, but how the expression and functional interaction of these genes determine the unique biology of wood remains largely unknown. We used the soc1ful loss of function mutant - the woodiest genotype known in the otherwise herbaceous model plant Arabidopsis - to investigate the expression and interactions of genes involved in secondary growth (wood formation). Detailed anatomical observations of the stem in combination with mRNA sequencing were used to assess transcriptome remodeling during xylogenesis in wild-type and woody soc1ful plants. To interpret the transcriptome changes, we constructed functional gene association networks of differentially expressed genes using the STRING database. This analysis revealed functionally enriched gene association hubs that are differentially expressed in herbaceous and woody tissues. In particular, we observed the differential expression of genes related to mechanical stress and jasmonate biosynthesis/signaling during wood formation in soc1ful plants that may be an effect of greater tension within woody tissues. Our results suggest that habit shifts from herbaceous to woody life forms observed in many angiosperm lineages could have evolved convergently by genetic changes that modulate the gene expression and interaction network, and thereby redeploy the conserved wood developmental program. © 2016 The Authors. The Plant Journal published by Society for Experimental Biology and John Wiley & Sons Ltd.

  3. Selection and Vegetative Propagation of Native Woody Plants for Water-Wise Landscaping

    OpenAIRE

    Rupp, Larry A; Varga, William A; Anderson, David

    2011-01-01

    Native woody plants with ornamental characteristics such as brilliant fall color, dwarf form, or glossy leaves have potential for use in water conserving urban landscapes. Individual accessions with one or more of these unique characteristics were identified based on the recommendations of a wide range of plant enthusiasts (both professional and amateur). Documentation of these accessions has been done through locating plants on-site where possible and then developing a record based on digita...

  4. Phylogenetic diversity of macromycetes and woody plants along an elevational gradient in Eastern Mexico

    Science.gov (United States)

    Marko Gomez-Hernandez; Guadalupe Williams-Linera; D. Jean Lodge; Roger Guevara; Eduardo Ruiz-Sanchez; Etelvina Gandara

    2016-01-01

    Phylogenetic information provides insight into the ecological and evolutionary processes that organize species assemblages. We compared patterns of phylogenetic diversity among macromycete and woody plant communities along a steep elevational gradient in eastern Mexico to better understand the evolutionary processes that structure their communities. Macrofungi and...

  5. Woody plants in agro-ecosystems of semi-arid regions

    NARCIS (Netherlands)

    Breman, H.; Kessler, J.J.

    1995-01-01

    A quantitative analysis of the role of woody plants in semi-arid regions, focusing on the Sahel and Sudan zones in West-Africa, is given for the assessment of their benefits in agro-sylvopastoral land-use systems with productive and sustainability objectives.

  6. Woody plant diversity in sacred forests and fallows in Chiang Mai, Thailand

    DEFF Research Database (Denmark)

    Junsongduang, A.; Balslev, Henrik; Jampeetong, Arunothai

    2014-01-01

    All woody plant and seedling diversity was compared in a Karen and a Lawa hill-tribe village in northern Thailand in four different habitats: sacred forests and fallow fields of three ages derived from rotational shifting cultivation (young fallows, 1–2 years old; medium-age fallow, 3-4 years old...

  7. A Plumber's-Eye View of Xylem Water Transport in Woody Plants

    Science.gov (United States)

    Martinez-Vilalta, Jordi; Pinol, Josep

    2004-01-01

    We present a practical for university-level students aimed at measuring and comparing xylem hydraulic properties of co-existing plant species. After sampling branches of several woody species in the field, their main hydraulic properties were measured using a simple set-up. Hydraulic conductivity ("K[subscript h]") was calculated as the ratio…

  8. Geographical patterns in the beta diversity of China's woody plants

    DEFF Research Database (Denmark)

    Wang, Zhiheng; Fang, Jingyun; Tang, Zhiyao

    2012-01-01

    Beta diversity (i.e. species turnover rate across space) is fundamental for understanding mechanisms controlling large-scale species richness patterns. However, the influences on beta diversity are still a matter of debate. In particular, the relative role of environmental and spatial processes (e.......g. environmental niche versus dispersal limitation of species) remains elusive, and the influence of species range size has been poorly tested. Here, using distribution maps of 11 405 woody species in China (ca 9.6 ¿ 106 km2), we investigated 1) the geographical and directional patterns of beta diversity for all...... with their environmental niches due to dispersal limitation induced by China’s topography and/or their low dispersal ability. The projected rapid climatic changes will likely endanger such species. Species dispersal processes should be taken into account in future conservation strategies in China....

  9. Ethnobotanical survey of \\'wild\\' woody plant resources at Mount ...

    African Journals Online (AJOL)

    Kasigau Taita named 252 of these plants and described 758 material uses or ecosystem services for 205 plants. Most plants with uses occurred in montane woodland (650–1000 m), the bushland (1000 m) had a described use.

  10. Molecular Phytopathology: Current Approaches and Main Directions in Diagnostics of Woody Plant Diseases

    Directory of Open Access Journals (Sweden)

    O. Yu. Baranov

    2014-08-01

    Full Text Available In the article the authors describe the prospects for diagnosis of woody plants diseases based on the use of modern methods of molecular plant pathology. The metagenomic approach based on the analysis of complex pathogens, including non-pathogenic microflora is described. The use the multicopy universal loci characterized by a number of advantages in determining taxonomic affiliation of infectious agents during phytopathological molecular analysis is proposed.

  11. Long-term effects of burning on woody plant species sprouting on the False thornveld of Eastern Cape

    CSIR Research Space (South Africa)

    Ratsele, C

    2010-11-01

    Full Text Available Sprouting allows woody plant species to persist in a site after a wide range of disturbances (e.g. prolonged fire), where opportunities for seedling establishment are limited. A study to investigate long-term effects of fire sprouting of woody...

  12. Survival, reproduction, and recruitment of woody plants after 14 years on a reforested landfill

    Science.gov (United States)

    Robinson, George R.; Handel, Steven N.; Schmalhofer, Victoria R.

    1992-03-01

    With the advent of modern sanitary landfill closure techniques, the opportunity exists for transforming municipal landfills into urban woodlands. While costs of fullscale reforestation are generally prohibitive, a modest planting of clusters of trees and shrubs could initiate or accelerate population expansions and natural plant succession from open field to diverse forest. However, among woody species that have been screened for use on landfills, these ecological potentials have not yet been investigated. We examined a 14-yr-old landfill plantation in New Jersey, USA, established to test tolerance of 19 species of trees and shrubs to landfill environments. We measured survivorship, reproduction, and recruitment within and around the experimental installation. Half of the original 190 plants were present, although survival and growth rates varied widely among species. An additional 752 trees and shrubs had colonized the plantation and its perimeter, as well as 2955 stems of vines. However, the great majority (>95%) of woody plants that had colonized were not progeny of the planted cohort, but instead belonged to 18 invading species, mostly native, bird-dispersed, and associated with intermediate stages of secondary plant succession. Based on this evidence, we recommend that several ecological criteria be applied to choices of woody species for the restoration of municipal landfills and similar degraded sites, in order to maximize rapid and economical establishment of diverse, productive woodlands.

  13. Facilitation between woody and herbaceous plants that associate with arbuscular mycorrhizal fungi in temperate European forests.

    Science.gov (United States)

    Veresoglou, Stavros D; Wulf, Monika; Rillig, Matthias C

    2017-02-01

    In late-successional environments, low in available nutrient such as the forest understory, herbaceous plant individuals depend strongly on their mycorrhizal associates for survival. We tested whether in temperate European forests arbuscular mycorrhizal (AM) woody plants might facilitate the establishment of AM herbaceous plants in agreement with the mycorrhizal mediation hypothesis. We used a dataset spanning over 400 vegetation plots in the Weser-Elbe region (northwest Germany). Mycorrhizal status information was obtained from published resources, and Ellenberg indicator values were used to infer environmental data. We carried out tests for both relative richness and relative abundance of herbaceous plants. We found that the subset of herbaceous individuals that associated with AM profited when there was a high cover of AM woody plants. These relationships were retained when we accounted for environmental filtering effects using path analysis. Our findings build on the existing literature highlighting the prominent role of mycorrhiza as a coexistence mechanism in plant communities. From a nature conservation point of view, it may be possible to promote functional diversity in the forest understory through introducing AM woody trees in stands when absent.

  14. Host range of Phytophthora parsiana: a new high temperature pathogen of woody plants

    Directory of Open Access Journals (Sweden)

    Somieh HAJEBRAHIMI

    2011-05-01

    Full Text Available Normal 0 14 false false false IT ZH-TW X-NONE MicrosoftInternetExplorer4 Among several Phytophthora spp. reported previously from Pistacia vera in Iran, a high temperature species recently identified as P. parsiana (formerly known as high temperature P. cryptogea is becoming important in woody plants, including P. vera. The host range of this newly recognised species, including both annual and perennial plants, is reported here. The pathogen infected 4–5 month-old glasshouse grown seedlings of P. vera, Ficus carica, Malus pumila and Prunus dulcis, and detached stems of 23 woody plants collected during dormant and growing seasons. Nineteen field and vegetable crops and 17 weed species were not infected by  P. parsiana in these pathogenicity assays.

  15. Inventory of Green Spaces and Woody Plants in the Urban Landscape in Ariogala

    Directory of Open Access Journals (Sweden)

    Lina Straigytė

    2012-12-01

    Full Text Available Background and Purpose: Regulation of urban greenery design, management and protection was approved in 2008 in Lithuania after the Green Space Law was passed, allowing protection of public green spaces and woody plants. Protection of these resources first requires an inventory, and we have created a digital database that will help in management of urban green spaces. Material and Methods: An inventory of green spaces and woody plants was conducted in the public urban territory of Ariogala, using GIS technology. A digital cartographic database was created using ArcGis 9.1 software. Results and Conclusion: Most of the woody plants in the survey area are deciduous trees, and the survey results highlighted the major green space management problems. Often, planted trees grow under power lines, and their crowns touch the power cables. Near blocks of flats, trees are often in the wrong place-planted too close to buildings, trees shade windows and their roots heave pavers and penetrate building foundations. According to the inventory, street trees sustain the most damage, most commonly showing injuries on their trunks and roots. Leaves of Aesculus hipocastanum L. show massive damage from Cameraria ohridella Deschka & Dimić, and Tilia cordata Mill. are damaged by Cercospora microsora Sacc. T. cordata is a favourite city tree, but is susceptible to infestation and when damaged appears unsightly, ending its vegetation period very early. The inventory of green spaces also showed that there are sufficient public parks.

  16. The effect of clay amendment on substrate properties and growth of woody plants

    Directory of Open Access Journals (Sweden)

    Tomáš Meisl

    2012-01-01

    Full Text Available This work deals with the effect of two clay products differing in particle size distribution on properties of growing substrate and on growth of containerized woody plants in substrates amended with these clay products. Fine and coarse clay were added to a peat substrate, each at two rates. The peat substrate without clay was used as a control. The substrates were tested in experiments with two woody ornamentals (Thuja occidentalis ’Smaragd’ and Prunus cistena. Chemical and physical properties of the substrates were measured according to European Standards before planting. Proportion of water categories differing in availability to the plants were calculated from retention curves measured on the sand box. Properties of substrates in containers with and without plants were evaluated in the same way at the end of the culture. Clay addition changed chemical and physical properties of the tested substrates in terms: available nutrients content, particle density, bulk density, total pore volume, easy available water, water buffering capacity, air capacity, and shrinkage. The effect of fine clay was much stronger. In comparison with the clear effect of clay addition on the substrate chemical and physical properties, the effect on the growth and quality of model woody plants was not so explicit.

  17. Use of plant woody species electrical potential for irrigation scheduling.

    Science.gov (United States)

    Ríos-Rojas, Liliana; Morales-Moraga, David; Alcalde, José A; Gurovich, Luis A

    2015-01-01

    The electrical response of plants to environmental stimuli can be measured and quantitatively related to the intensity of several stimulating sources, like temperature, solar radiation, soil water content, evapotranspiration rates, sap flow and dendrometric cycles. These relations can be used to assess the influence of different environmental situations on soil water availability to plants, defined as a steady state condition between leaf transpirative flow and soil water flow to plant roots. A restricted soil water flow due to soil dryness can trigger water stress in plants, if the atmospheric evaporative demand is high, causing partial stomata closure as a physiological response to avoid plant dehydration; water stressed and unstressed plants manifest a differential electrical response. Real time plant electrical response measurements can anticipate actions that prevent the plant reaching actual stress conditions, optimizing stomata gas exchange and photosynthetic rates. An electrophysiological sensor developed in this work, allows remote real-time recording information on plant electrical potential (EP) in the field, which is highly related to EP measurements obtained with a laboratory Keithley voltmeter sensor used in an highly controlled experimental setup. Our electrophysiological sensor is a wireless, autonomous devise, which transmits EP information via Internet to a data server. Using both types of sensors (EP electrodes with a Keithley voltmeter and the electrophysiological sensor), we measured in real time the electrical responses of Persea americana and Prunus domestica plants, to induced water deficits. The differential response for 2 scenarios: irrigation and water restriction is identified by a progressive change in slope on the daily maximal and minimal electric signal values in stressed plants, and a zero-slope for similar signals for well-watered plants. Results show a correspondence between measured signals obtained by our electrophysiological

  18. BAAD: a biomass and allometry database for woody plants

    Science.gov (United States)

    Daniel S. Falster; Remko A. Duursma; Masae I. Ishihara; Diego R. Barneche; Richard G. FitzJohn; Angelica Varhammar; Masahiro Aiba; Makoto Ando; Niels Anten; Michael J. Aspinwall; Jennifer L. Baltzer; Christopher Baraloto; Michael Battaglia; John J. Battles; Ben Bond-Lamberty; Michiel van Breugel; Yves Claveau; Masako Dannoura; Sylvain Delagrange; Jean-Christophe Domec; Farrah Fatemi; Wang Feng; Veronica Gargaglione; Yoshiaki Goto; Akio Hagihara; Jefferson S. Hall; Steve Hamilton; Degi Harja; Tsutom Hiura; Robert Holdaway; Lindsay S. Hutley; Tomoaki Ichie; Eric J. Jokela; Anu Kantola; Jeff W. G. Kelly; Tanaka Kenzo; David King; Brian D. Kloeppel; Takashi Kohyama; Akira Komiyama; Jean-Paul Laclau; Christopher H. Lusk; Douglas A. Maguire; Guerric Le Maire; Ammikki Makela; Lars Markesteijn; John Marshall; Katherine McCulloh; Itsuo Miyata; Karel Mokany; Shugeta Mori; Randall W. Myster; Masahiro Nagano; Shawna L. Naidu; Yann Nouvellon; Anthony P. O' Grady; Kevin L. O' Hara; Toshiyuki Ohtsuka; Noriyuki Osada; Olusegun O. Osunkoya; Pablo Luis Peri; Any Mary Petritan; Lourens Poorter; Angelika Portsmuth; Catherine Potvin; Johannes Ransijn; Douglas Reid; Sabina C. Ribeiro; Scott D. Roberts; Rolando Rodriguez; Angela Saldana-Acosta; Ignacio Santa-Regina; Kaichiro Sasa; N. Galia Selaya; Stephen C. Sillett; Frank Sterck; Kentaro Takagi; Takeshi Tange; Hiroyuki Tanouchi; David Tissue; Toru Umehara; Matthew A. Vadeboncoeur; Fernando Valladares; Petteri Vanninen; Jian R. Wang; Elizabeth Wenk; Richard Williams; Fabiano de Aquino Ximenes; Atsushi Yamaba; Toshihiro Yamada; Takuo Yamakura; Ruth D. Yanai; Robert A. York

    2015-01-01

    Understanding how plants are constructed—i.e., how key size dimensions and the amount of mass invested in different tissues varies among individuals—is essential for modeling plant growth, carbon stocks, and energy fluxes in the terrestrial biosphere. Allocation patterns can differ through ontogeny, but also among coexisting species and among species adapted to...

  19. Ethnobotanical survey of \\'wild\\' woody plant resources at Mount ...

    African Journals Online (AJOL)

    This paper focuses on the naming and use of plants by Taita who live at Mount Kasigau in Kenya's Eastern Arc Mountains. Plant vouchers and ethnobotanical data were compiled from transects and within 55 ecological plots, and during participant observations, home surveys, and semi-structured interviews with residents.

  20. Preliminary study on space mutagenesis of mutagenesis of three species of woody plants

    International Nuclear Information System (INIS)

    Lu Chao; Yuan Cunquan; Li Yun; Xi Yang

    2010-01-01

    Dry seeds of three woody plants, Xanthoceras sorbifolia, Acer mono and Robiniap pseudoacacia, were carried into space by the return satellite for mutation breeding. The seed vigor,leaf pigments of seedlings, MDA contents and growth volume were analyzed. Compared with the earth control, the seed vigor of three woody plants were extremely improved by space-induced mutation, the seed germination rate, planting and survival rate of seedlings were all higher than those of earth control, and the MDA contents of Xanthoceras sorbifolia and Acer mono were declined. The leaf pigments content of the trees were all lower than those of the control, specially Robinia pseudoacacia and Acer mono, which were both significantly different from their control at 0.01 levels. The growth volume of the mutation group were inhibited in the first year; however, from the second year, the growth of Xanthoceras sorbifolia and Acer mono were faster than those of control, indicating that the space mutation can promote the seed vigor and seedling resistance of three woody plants. (authors)

  1. Relative role of contemporary environment versus history in shaping diversity patterns of China's woody plants

    DEFF Research Database (Denmark)

    Wang, Zhiheng; Fang, Jingyun; Tang, Zhiyao

    2012-01-01

    What determines large-scale patterns of species diversity is a central and controversial topic in biogeography and ecology. In this study, we compared the effects of contemporary environment and historical contingencies on species richness patterns of woody plants in China, using fine-resolution ......-plant species richness across China, while historical contingencies generate regional deviations from this trend. Our findings imply that both species diversity and regional evolutionary and ecological histories should be taken into account for future nature conservation......., and the Tibetan Plateau, perhaps reflecting their special geological features and history. Nevertheless, partial regression indicated that historical effects were less important relative to contemporary environment. In conclusion, contemporary environment (notably climate) determines the general trend in woody...

  2. The potential impact of invasive woody oil plants on protected areas in China under future climate conditions.

    Science.gov (United States)

    Dai, Guanghui; Yang, Jun; Lu, Siran; Huang, Conghong; Jin, Jing; Jiang, Peng; Yan, Pengbo

    2018-01-18

    Biodiesel produced from woody oil plants is considered a green substitute for fossil fuels. However, a potential negative impact of growing woody oil plants on a large scale is the introduction of highly invasive species into susceptible regions. In this study, we examined the potential invasion risk of woody oil plants in China's protected areas under future climate conditions. We simulated the current and future potential distributions of three invasive woody oil plants, Jatropha curcas, Ricinus communis, and Aleurites moluccana, under two climate change scenarios (RCP2.6 and RCP8.5) up to 2050 using species distribution models. Protected areas in China that will become susceptible to these species were then identified using a spatial overlay analysis. Our results showed that by 2050, 26 and 41 protected areas would be threatened by these invasive woody oil plants under scenarios RCP2.6 and RCP8.5, respectively. A total of 10 unique forest ecosystems and 17 rare plant species could be potentially affected. We recommend that the invasive potential of woody oil plants be fully accounted for when developing forest-based biodiesel, especially around protected areas.

  3. Will woody plant encroachment impact the visitor experience and economy of conservation areas?

    Directory of Open Access Journals (Sweden)

    Emma F. Gray

    2013-08-01

    Conservation implications: The results pointed to potentially significant economic consequences for conservation efforts as visitors become less satisfied with their experience. Perceptions of visitors are important for management decisions as park fees contribute significantly to conservation efforts. This could ultimately result in a reduced capacity for African conservation areas to conserve their biodiversity effectively. The results suggest that management may need to re-evaluate their approach to controlling woody plant encroachment.

  4. Evaluating nurse plants for restoring native woody species to degraded subtropical woodlands.

    Science.gov (United States)

    Yelenik, Stephanie G; DiManno, Nicole; D'Antonio, Carla M

    2015-01-01

    Harsh habitats dominated by invasive species are difficult to restore. Invasive grasses in arid environments slow succession toward more desired composition, yet grass removal exacerbates high light and temperature, making the use of "nurse plants" an appealing strategy. In this study of degraded subtropical woodlands dominated by alien grasses in Hawai'i, we evaluated whether individuals of two native (Dodonaea viscosa, Leptocophylla tameiameia) and one non-native (Morella faya) woody species (1) act as natural nodes of recruitment for native woody species and (2) can be used to enhance survivorship of outplanted native woody species. To address these questions, we quantified the presence and persistence of seedlings naturally recruiting beneath adult nurse shrubs and compared survival and growth of experimentally outplanted seedlings of seven native woody species under the nurse species compared to intact and cleared alien-grass plots. We found that the two native nurse shrubs recruit their own offspring, but do not act as establishment nodes for other species. Morella faya recruited even fewer seedlings than native shrubs. Thus, outplanting will be necessary to increase abundance and diversity of native woody species. Outplant survival was the highest under shrubs compared to away from them with few differences between nurse species. The worst habitat for native seedling survival and growth was within the unmanaged invasive grass matrix. Although the two native nurse species did not differentially affect outplant survival, D. viscosa is the most widespread and easily propagated and is thus more likely to be useful as an initial nurse species. The outplanted species showed variable responses to nurse habitats that we attribute to resource requirements resulting from their typical successional stage and nitrogen fixation capability.

  5. Woody plants in drylands: plastic responses to environmental stress

    NARCIS (Netherlands)

    Xu, L.

    2012-01-01

    Plants in drylands are exposed to a suite of stress factors. The most obvious stress factor is drought stress induced by a strongly negative balance between precipitation and potential evapotranspiration. Drylands are increasingly being used for grazing livestock and with increasing human

  6. Growth responses and metal accumulation capabilities of woody plants during the phytoremediation of tannery sludge.

    Science.gov (United States)

    Shukla, O P; Juwarkar, Asha A; Singh, S K; Khan, Shoeb; Rai, U N

    2011-01-01

    Five woody plants species (i.e. Terminalia arjuna, Prosopis juliflora, Populus alba, Eucalyptus tereticornis and Dendrocalamus strictus) were selected for phytoremediation and grow on tannery sludge dumps of Common Effluent Treatment Plant (CETP), Unnao (Uttar Pradesh), India. Concentration of toxic metals were observed high in the raw tannery sludge i.e. Fe-1667>Cr-628>Zn-592>Pb-427>Cu-354>Mn-210>Cd-125>Ni-76 mg kg(-1) dw, respectively. Besides, physico-chemical properties of the raw sludge represented the toxic nature to human health and may pose numerous risks to local environment. The growth performances of woody plants were assessed in terms of various growth parameters such as height, diameter at breast height (DBH) and canopy area of plants. All the plant species have the capabilities to accumulate substantial amount of toxic metals in their tissues during the remediation. The ratio of accumulated metals in the plants were found in the order Fe>Cr>Mn>Pb>Zn>Cu>Cd>Ni and significant changes in physico-chemical parameters of tannery sludge were observed after treatment. All the woody plants indicated high bioconcentration factor for different metals in the order Fe>Cr>Mn>Ni>Cd>Pb>Zn>Cu. After one year of phytoremediation, the level of toxic metals were removed from tannery sludge up to Cr (70.22)%, Ni (59.21)%, Cd (58.4)%, Fe (49.75)%, Mn (30.95)%, Zn (22.80)%, Cu (20.46)% and Pb (14.05)%, respectively. Copyright © 2010 Elsevier Ltd. All rights reserved.

  7. Assessing the Roles of Fire Frequency and Precipitation in Determining Woody Plant Expansion in Central U.S. Grasslands

    Science.gov (United States)

    Brunsell, N. A.; Van Vleck, E. S.; Nosshi, M.; Ratajczak, Z.; Nippert, J. B.

    2017-10-01

    Woody plant expansion into grasslands and savannas is occurring and accelerating worldwide and often impacts ecosystem processes. Understanding and predicting the environmental and ecological impacts of encroachment has led to a variety of methodologies for assessing its onset, transition, and stability, generally relying on dynamical systems approaches. Here we continue this general line of investigation to facilitate the understanding of the roles of precipitation frequency and intensity and fire frequency on the conversion of grasslands to woody-dominated systems focusing on the central United States. A low-dimensional model with stochastic precipitation and fire disturbance is introduced to examine the complex interactions between precipitation and fire as mechanisms that may suppress or facilitate increases in woody cover. By using Lyapunov exponents, we are able to ascertain the relative control exerted on woody encroachment through these mechanisms. Our results indicate that precipitation frequency is a more important control on woody encroachment than the intensity of individual precipitation events. Fire, however, exerts a much more dominant impact on the limitation of encroachment over the range of precipitation variability considered here. These results indicate that fire management may be an effective strategy to slow the onset of woody species into grasslands. While climate change might predict a reduced potential for woody encroachment in the near future, these results indicate a reduction in woody fraction may be unlikely when considering anthropogenic fire suppression.

  8. 40K/137Cs discrimination ratios to the aboveground organs of tropical plants

    International Nuclear Information System (INIS)

    Sanches, N.; Anjos, R.M.; Mosquera, B.

    2008-01-01

    In the present work, the accumulation of caesium and potassium in aboveground plant parts was studied in order to improve the understanding on the behaviour of monovalent cations in several compartments of tropical plants. We present the results for activity concentrations of 137 Cs and 40 K, measured by gamma spectrometry, from five tropical plant species: guava (Psidium guajava), mango (Mangifera indica), papaya (Carica papaya), banana (Musa paradisiaca), and manioc (Manihot esculenta). Caesium and potassium have shown a high level of mobility within the plants, exhibiting the highest values of concentration in the growing parts (fruits, leaves, twigs, and barks) of the woody fruit and large herbaceous shrub (such as manioc) species. In contrast, the banana and papaya plants exhibited the lowest levels of 137 Cs and 40 K in their growing parts. However, a significant correlation between activity concentrations of 137 Cs and 40 K was observed in these tropical plants. The 40 K/ 137 Cs discrimination ratios were approximately equal to unity in different compartments of each individual plant, suggesting the possibility of using caesium to predict the behaviour of potassium in several tropical species

  9. {sup 40}K/{sup 137}Cs discrimination ratios to the aboveground organs of tropical plants

    Energy Technology Data Exchange (ETDEWEB)

    Sanches, N. [Instituto de Fisica, Universidade Federal Fluminense, Av. Gal. Milton Tavares de Souza s/n, Gragoata, Niteroi, CEP 24210-346, RJ (Brazil); Anjos, R.M. [Instituto de Fisica, Universidade Federal Fluminense, Av. Gal. Milton Tavares de Souza s/n, Gragoata, Niteroi, CEP 24210-346, RJ (Brazil)], E-mail: meigikos@if.uff.br; Mosquera, B. [Instituto de Fisica, Universidade Federal Fluminense, Av. Gal. Milton Tavares de Souza s/n, Gragoata, Niteroi, CEP 24210-346, RJ (Brazil)

    2008-07-15

    In the present work, the accumulation of caesium and potassium in aboveground plant parts was studied in order to improve the understanding on the behaviour of monovalent cations in several compartments of tropical plants. We present the results for activity concentrations of {sup 137}Cs and {sup 40}K, measured by gamma spectrometry, from five tropical plant species: guava (Psidium guajava), mango (Mangifera indica), papaya (Carica papaya), banana (Musa paradisiaca), and manioc (Manihot esculenta). Caesium and potassium have shown a high level of mobility within the plants, exhibiting the highest values of concentration in the growing parts (fruits, leaves, twigs, and barks) of the woody fruit and large herbaceous shrub (such as manioc) species. In contrast, the banana and papaya plants exhibited the lowest levels of {sup 137}Cs and {sup 40}K in their growing parts. However, a significant correlation between activity concentrations of {sup 137}Cs and {sup 40}K was observed in these tropical plants. The {sup 40}K/{sup 137}Cs discrimination ratios were approximately equal to unity in different compartments of each individual plant, suggesting the possibility of using caesium to predict the behaviour of potassium in several tropical species.

  10. 40K/137Cs discrimination ratios to the aboveground organs of tropical plants.

    Science.gov (United States)

    Sanches, N; Anjos, R M; Mosquera, B

    2008-07-01

    In the present work, the accumulation of caesium and potassium in aboveground plant parts was studied in order to improve the understanding on the behaviour of monovalent cations in several compartments of tropical plants. We present the results for activity concentrations of (137)Cs and (40)K, measured by gamma spectrometry, from five tropical plant species: guava (Psidium guajava), mango (Mangifera indica), papaya (Carica papaya), banana (Musa paradisíaca), and manioc (Manihot esculenta). Caesium and potassium have shown a high level of mobility within the plants, exhibiting the highest values of concentration in the growing parts (fruits, leaves, twigs, and barks) of the woody fruit and large herbaceous shrub (such as manioc) species. In contrast, the banana and papaya plants exhibited the lowest levels of (137)Cs and (40)K in their growing parts. However, a significant correlation between activity concentrations of (137)Cs and (40)K was observed in these tropical plants. The (40)K/(137)Cs discrimination ratios were approximately equal to unity in different compartments of each individual plant, suggesting the possibility of using caesium to predict the behaviour of potassium in several tropical species.

  11. Eleventh-year response of loblolly pine and competing vegetation to woody and herbaceous plant control on a Georgia flatwoods site

    Science.gov (United States)

    Bruce R. Zutter; James H. Miller

    1998-01-01

    Through 11 growing seasons, growth of loblolly pine (Pinus taeda L.) increased after control of herbaceous, woody, or both herbaceous and woody vegetation (total control) for the first 3 years after planting on a bedded site in the Georgia coastal flatwoods. Gains in stand volume index from controlling either herbaceous or woody vegetation alone were approximately two-...

  12. Woody plant encroachment effect on soil organic carbon dynamics: results from a latitudinal gradient in Italy

    Science.gov (United States)

    Pellis, Guido; Chiti, Tommaso; Moscatelli, Maria Cristina; Marinari, Sara; Papale, Dario

    2016-04-01

    Woody plant encroachment into pastures and grasslands represents a significant land cover change phenomenon, with a considerable impact on carbon dynamics at an ecosystem level. It was estimated that 7.64% of the Southern Europe land was subject to that process between 1950 to 2010. As a result of woody encroachment, changes in vegetation composition can produce substantial changes to the soil organic carbon (SOC) cycle. Despite the numerous papers published on land-use change, an evaluation of the IPCC terrestrial carbon pools changes occurring during woody encroachment on abandoned pastures and grasslands is still lacking, particularly for the Italian territory. Therefore, the aim of this study was to investigate the role of woody encroachment on carbon sequestration over abandoned pastures and grasslands in Alpine and Apennine ecosystems, with a particular focus on the SOC. We applied a chronosequence approach to seven selected sites located along a latitudinal gradient in Italy. Each chronosequence consisted of a pasture currently managed, three sites abandoned at different times in the past and, finally, a mature forest stand representing the last phase of the succession. The European Commission sampling protocols to certify SOC changes was adopted to estimate the variations following woody encroachment. Soil samples were collected at different depths in the topsoil (0-30 cm) and subsoil (30-70 cm), despite the original protocol formulation being limited to the topsoil only. In addition, aboveground living biomass (AGB), dead wood and litter were also measured following international protocols. Considering all C pools together, woody plant encroachment leads to a progressive C stock accumulation in all the chronosequences. The total C stock of mature forest stands ranges from 1.78±0.11 times (Eastern Alps) to 2.48±0.31 times (central Apennine) the initial value on pastures. Unsurprisingly, the C stocks of AGB, dead wood and litter all increase during the

  13. In-vitro neoformation of woody plants (apple, pear, Weigela)

    International Nuclear Information System (INIS)

    Chevreau, E.; Dufour, M.; Duron, M.

    1990-01-01

    Full text: Adventitious bud neoformation may induce variability in two ways: somaclonal variation, if the explant has undergone undifferentiated growth (callus); induced mutations, if a physical or chemical mutagen has been applied to the explant prior to the regeneration. Three apple scion cultivars ('Gala', 'Granny Smith', 'Golden Delicious') and four apple rootstock cultivars ('Mark', 'Novole', 'Lancep', 'Cepiland') were grown on basal apple multiplication medium. Leaves, internodes and roots were used for callogenesis and/or regeneration experiments. Scion varieties were more responsive than rootstocks. 1000 'Gala' neoformations will be planted in the field to investigate somaclonal variation. In pear, shoot regeneration was obtained from in-vitro leaves of 3 varieties of Pyrus communis ('Seckel', 'Louise Bonne', 'Comice') and one variety of Pyrus bretschneideri ('Crystal Pear'). It was observed that regeneration is still possible from leaves irradiated with up to 40 Gy of γ rays, or treated with 5mM ENU for one hour. In Weigela, stem segments (0.5 cm) from rooted in vitro plants of 5 cultivars were used in experiments to induce adventitious buds. On the cultivar 'Eva Rathke' the adventitious buds were detected as early as 10 to 15 days after the beginning of the culture. A mutagenic treatment was carried out by immersing explants of 'Bristol Ruby' in a suspension of ethyl methane sulfonate (EMS). Among 400 plants regenerated from treated explants, 5 mutants were detected after 5 years of field observation. Two of them seem to be solid mutants. Apparently in Weigela both homogeneous mutants and chimeras are produced by adventitious regeneration from mutagenised explants. (author)

  14. From gene manipulation to forest establishment: shoot cultures of woody plants can be a central tool

    Energy Technology Data Exchange (ETDEWEB)

    McCown, B.H.

    1985-05-01

    Establishing germplasm of woody plants in microculture as shoot cultures has proved to be an effective method of overcoming many of the obstacles in working with these crops. Shoot cultures eliminate the changes associated with seasonal growth cycles and phase change and put large plants into a more manageable form. Well-established shoot cultures are central to successful clonal propagation systems for forest trees as well as to genetic improvement based on the use of cellular techniques such as protoplast manipulation. The physiological basis as to why tissues from shoot cultures are so readily manipulated is not well understood.

  15. Temperate and Tropical Plant Collections

    DEFF Research Database (Denmark)

    Friis, Ib

    2015-01-01

    The first botanical gardens and collections of preserved plants in the 16th century served didactic purposes and should ensure correct identification of medicinal, ornamental and other useful plants. Collections of preserved plants were nearly all book-herbaria, emulating illustrated books...... and owned by individual botanists. Curiosity cabinets of nobles and prominent scholars were larger collections, in which all kinds of objects of natural history from remote regions could be incorporated. The Linnaean revolution favoured loose-leaf herbaria over the old book-herbaria: herbaria with loose...... sheets could be reorganised in agreement with new knowledge or theories and newly accessed specimens could be placed next to earlier ones of the same species. However, the Linnaean collections reflected the essentialist species concept, according to which all species consisted of individuals with similar...

  16. Woody plant willow in function of river water protection

    Directory of Open Access Journals (Sweden)

    Babincev Ljiljana M.

    2011-01-01

    Full Text Available Coastal area surrounding the river Ibar, in the area between cities of Kosovska Mitrovica and Leposavić in the north of Kosovo and Metohija, is occupied with seven industrial waste dumps. These dumps were all part of the exploitation and flotation refinement of raw mineral materials, metallurgic refinement of concentrates, chemical industry, industrial refinement and energetic facilities of Trepča industrial complex. The existing waste dumps, both active and inactive, are of heterogenic chemical composition. Its impact on the river water is shown by the content of heavy metals found in it. Removal of lead, cadmium and zinc would be economically unrewarding, regardless of the technology used. Wooden plant that prevails in this area is white willow. This work is focused on the removal of heavy metals (Pb, Cd and Zn from the water of the river Ibar using white willow. Roots of the willow are cultivated using the method of water cultures in an individual solution of heavy metals and river water sample. The preparation of the samples for analysis was performed by burning the herbal material and dissolving ashes in the appropriate acids. The concentrations of metals were determined by the stripping analysis. In the investigated heavy metal solutions the biomass increase is 25.6% in lead solution, 27.3% in cadmium and 30.7% in zinc solution. The increase of biomass in nutritional solution, without the heavy metals, is 32.4% and in river water sample 27.5%. The coefficient of bioaccumulation in solutions with heavy metals is 1.6% in lead solution, 1.9% in cadmium and 2.2% in zinc solution. Heavy metals accumulation is 18.74 μg of lead, 20.09 μg of cadmium and 22.89 μg of zinc. The coefficient of bioaccumulation of the water samples, that contained 44.83 μg/dm3 of lead, 29.21 μg/dm3 of cadmium and 434.00 μg/dm3 of zinc, during the period of 45 days, was 30.3% for lead, 53.4% for cadmium and 3.9% for zinc. The concentrations of accumulated metals

  17. Monoterpene engineering in a woody plant Eucalyptus camaldulensis using a limonene synthase cDNA.

    Science.gov (United States)

    Ohara, Kazuaki; Matsunaga, Etsuko; Nanto, Kazuya; Yamamoto, Kyoko; Sasaki, Kanako; Ebinuma, Hiroyasu; Yazaki, Kazufumi

    2010-01-01

    Metabolic engineering aimed at monoterpene production has become an intensive research topic in recent years, although most studies have been limited to herbal plants including model plants such as Arabidopsis. The genus Eucalyptus includes commercially important woody plants in terms of essential oil production and the pulp industry. This study attempted to modify the production of monoterpenes, which are major components of Eucalyptus essential oil, by introducing two expression constructs containing Perilla frutescens limonene synthase (PFLS) cDNA, whose gene products were designed to be localized in either the plastid or cytosol, into Eucalyptus camaldulensis. The expression of the plastid-type and cytosol-type PFLS cDNA in transgenic E. camaldulensis was confirmed by real-time polymerase chain reaction (PCR). Gas chromatography with a flame ionization detector analyses of leaf extracts revealed that the plastidic and cytosolic expression of PFLS yielded 2.6- and 4.5-times more limonene than that accumulated in wild-type E. camaldulensis, respectively, while the ectopic expression of PFLS had only a small effect on the emission of limonene from the leaves of E. camaldulensis. Surprisingly, the high level of PFLS in Eucalyptus was accompanied by a synergistic increase in the production of 1,8-cineole and alpha-pinene, two major components of Eucalyptus monoterpenes. This genetic engineering of monoterpenes demonstrated a new potential for molecular breeding in woody plants.

  18. Gibberellin Promotes Shoot Branching in the Perennial Woody Plant Jatropha curcas.

    Science.gov (United States)

    Ni, Jun; Gao, Congcong; Chen, Mao-Sheng; Pan, Bang-Zhen; Ye, Kaiqin; Xu, Zeng-Fu

    2015-08-01

    Strigolactone (SL), auxin and cytokinin (CK) interact to regulate shoot branching. CK has long been considered to be the only key phytohormone to promote lateral bud outgrowth. Here we report that gibberellin also acts as a positive regulator in the control of shoot branching in the woody plant Jatropha curcas. We show that gibberellin and CK synergistically promote lateral bud outgrowth, and that both hormones influence the expression of putative branching regulators, J. curcas BRANCHED1 and BRANCHED2, which are key transcription factors maintaining bud dormancy. Moreover, treatment with paclobutrazol, an inhibitor of de novo gibberellin biosynthesis, significantly reduced the promotion of bud outgrowth by CK, suggesting that gibberellin is required for CK-mediated axillary bud outgrowth. In addition, SL, a plant hormone involved in the repression of shoot branching, acted antagonistically to both gibberellin and CK in the control of lateral bud outgrowth. Consistent with this, the expression of JcMAX2, a J. curcas homolog of Arabidopsis MORE AXILLARY GROWTH 2 encoding an F-box protein in the SL signaling pathway, was repressed by gibberellin and CK treatment. We also provide physiological evidence that gibberellin also induces shoot branching in many other trees, such as papaya, indicating that a more complicated regulatory network occurs in the control of shoot branching in some perennial woody plants. © The Author 2015. Published by Oxford University Press on behalf of Japanese Society of Plant Physiologists.

  19. Biodiversity of Soil Microbial Communities Following Woody Plant Invasion of Grassland: An Assessment Using Molecular Methods

    Science.gov (United States)

    Kantola, I. B.; Gentry, T. J.; Filley, T. R.; Boutton, T. W.

    2012-12-01

    Woody plants have encroached into grasslands, savannas, and other grass-dominated ecosystems throughout the world during the last century. This dramatic vegetation change is likely driven by livestock grazing, altered fire frequencies, elevated atmospheric CO2 concentrations, and/or changes in atmospheric deposition patterns. Woody invasion often results in significant changes in ecosystem function, including alterations in above- and belowground primary productivity, soil C, N, and P storage and turnover, and the size and activity of the soil microbial biomass pool. The purpose of this study was to examine the relationships and interactions between plant communities and soil microbial communities in the Rio Grande Plains region of southern Texas where grasslands have been largely replaced by woodlands. Research was conducted along a successional chronosequence representing the stages of woody plant encroachment from open grassland to closed-canopy woodland. To characterize soil microbial community composition, soil samples (0-7.5 cm) were collected in remnant grasslands (representing time 0) and near the centers of woody plant clusters, groves, and drainage woodlands ranging in age from 10 to 130 yrs. Ages of woody plant stands were determined by dendrochronology. Community DNA was extracted from each soil sample with a MoBio PowerMax Soil DNA isolation kit. The DNA concentrations were quantified on a NanoDrop ND-1000 spectrophotometer and diluted to a standard concentration. Pyrosequencing was performed by the Research and Testing Laboratory (Lubbock, TX) according to Roche 454 Titanium chemistry protocols. Samples were amplified with primers 27F and 519R for bacteria, and primers ITS1F and ITS4 for fungi. Sequences were aligned using BioEdit and the RDP Pipeline and analyzed in MOTHUR. Non-metric multidimensional scaling of the operational taxonomic units identified by pyrosequencing revealed that both bacterial and fungal community composition were

  20. An efficient DNA isolation method for tropical plants

    African Journals Online (AJOL)

    walkinnet

    2013-05-08

    May 8, 2013 ... 2Key Laboratory of Biology and Genetic Resources of Tropical Crops, Ministry of Agriculture, P. R. ... yielded high-quality DNA from 10 tropical plants including cassava, rubber tree, banana, etc. ..... Major Projects (GrantNo.

  1. KARO’S LOCAL WISDOM: THE USE OF WOODY PLANTS FOR TRADITIONAL DIABETIC MEDICINES

    Directory of Open Access Journals (Sweden)

    Rospita Odorlina Situmorang

    2015-12-01

    Full Text Available This paper identifies the plant species used traditionally by Karo people in North Sumatra, to cure diabetes, analyses the cultural significance index of those plants for the Karo, and clarifies phytochemical contents of the plants. Data were collected using survey method from selected respondents (n=54 based on their knowledge and practices in utilising medicinal plants to cure diabetic disease. Index of Cultural Significance (ICS of plants was determined using the method proposed by Turner. Results showed that twelve woody plant species have been used to cure diabetes: loning leave (Psychotria sp., kacihe leave (Prunus accuminta Hook, umbrella tree leave (Maesopsis eminii Engl, mutamba leave (Guazuma ulmifolia Lamk, cepcepan leave (Villebrunea subescens Blume, pirdot/cepcepan lembu leave (Saurauia vulcani Korth, raru bark (Cotylelobium melanoxylo, breadfruit leave (Artocarpus altilis, salam leave (Syzygium polyanthum Wight, mahogany seed (Swietenia mahagoni (L. Jacq, cinnamon bark (Cinnamomum burmani, and yellow bamboo rod (Bambusa vulgaris Schrad. Five of those plants: loning, umbrella tree, mutamba, raru and salam have the highest cultural significance level. These five plants are highly needed in large quatities by the Karo people, so their availability in the forest should be securely conserved and protected. The plants used contained alkaloids, flavonoids, phenolics and terpenoids which can help to lower blood sugar level.

  2. IMPACT OF WOODY PLANTS SPECIES ON SOIL PHYSIO-CHEMICAL PROPERTIES ALONG GRAZING GRADIENTS IN RANGELANDS OF EASTERN ETHIOPIA

    Directory of Open Access Journals (Sweden)

    Mohammed Mussa Abdulahi

    2016-12-01

    Full Text Available In the lowlands of arid and semiarid rangelands woody plants plays an important role in soil fertility maintenance, providing food, medicine, cosmetics, fodder, fuel wood and pesticides. A better understanding of the interaction of woody plants on their immediate environment is needed to guide optimum management of native vegetation in the production landscapes. However, the impact of woody plant species on soil properties remains poorly understood. This study evaluates the impact of two dominant woody plant species (A. senegal and B. aegyptica on soil physico-chemical properties along grazing gradients in rangelands of eastern Ethiopia. Six trees of each species were selected from light, moderate and heavy grazing sites.  Soil sample data at two depths (0-15 and 16-30 cm were collected from under and open areas of A. senegal and B. aegyptica from each grazing sites, and analysed for nutrient contents. The nutrient status of soil under both woody species was significantly higher especially with regard to soil organic matter (4.37%, total nitrogen (0.313%, and available phosphorus (11.62 than the open grassland with soil organic matter (3.82%, total nitrogen (0.246%, and available phosphorus (10.94 mg/Kg soil for A. Senegal. The soil organic matter (3.93%, total nitrogen (0.285%, available phosphorus (11.66 mg/Kg soil were significantly higher than open grassland with soil organic matter (3.52%, total nitrogen (0.218%, available phosphorus (10.73 mg/Kg soil for B. aegyptica. This was more pronounced in the top 15 cm of soil under A. senegal woody plant species and on the light and moderate grazing site. Therefore, this tree has a significant effect on soil fertility improvement in resource poor rangelands and as a result, it is important to retain scattered A. senegal and B. aegyptica plants in the lowlands of eastern Ethiopia.

  3. Using a botanical garden to assess factors influencing the colonization of exotic woody plants by phyllophagous insects.

    Science.gov (United States)

    Kirichenko, Natalia; Kenis, M

    2016-09-01

    The adoption of exotic plants by indigenous herbivores in the region of introduction can be influenced by numerous factors. A botanical garden in Western Siberia was used to test various hypotheses on the adaptation of indigenous phyllophagous insects to exotic plants invasions, focusing on two feeding guilds, external leaf chewers and leaf miners. A total of 150 indigenous and exotic woody plant species were surveyed for insect damage, abundance and species richness. First, exotic woody plants were much less damaged by chewers and leaf miners than native plants, and the leaf miners' species richness was much lower on exotic than native plants. Second, exotic woody plants having a congeneric species in the region of introduction were more damaged by chewers and hosted a more abundant and species-rich community of leaf miners than plants without native congeneric species. Third, damage by chewers significantly increased with the frequency of planting of exotic host plants outside the botanical garden, and leaf miners' abundance and species richness significantly increased with residence time in the garden. Finally, no significant relationship was found between insect damage or abundance and the origin of the exotic plants. Besides the ecological implications of the results, this study also illustrates the potential of botanical gardens to test ecological hypotheses on biological invasions and insect-plant interactions on a large set of plant species.

  4. Topo-edaphic controls over woody plant biomass in South African savannas

    Directory of Open Access Journals (Sweden)

    M. S. Colgan

    2012-05-01

    Full Text Available The distribution of woody biomass in savannas reflects spatial patterns fundamental to ecosystem processes, such as water flow, competition, and herbivory, and is a key contributor to savanna ecosystem services, such as fuelwood supply. While total precipitation sets an upper bound on savanna woody biomass, the extent to which substrate and terrain constrain trees and shrubs below this maximum remains poorly understood, often occluded by local-scale disturbances such as fire and trampling. Here we investigate the role of hillslope topography and soil properties in controlling woody plant aboveground biomass (AGB in Kruger National Park, South Africa. Large-area sampling with airborne Light Detection and Ranging (LiDAR provided a means to average across local-scale disturbances, revealing an unexpectedly linear relationship between AGB and hillslope-position on basalts, where biomass levels were lowest on crests, and linearly increased toward streams (R2 = 0.91. The observed pattern was different on granite substrates, where AGB exhibited a strongly non-linear relationship with hillslope position: AGB was high on crests, decreased midslope, and then increased near stream channels (R2 = 0.87. Overall, we observed 5-to-8-fold lower AGB on clayey, basalt-derived soil than on granites, and we suggest this is due to herbivore-fire interactions rather than lower hydraulic conductivity or clay shrinkage/swelling, as previously hypothesized. By mapping AGB within and outside fire and herbivore exclosures, we found that basalt-derived soils support tenfold higher AGB in the absence of fire and herbivory, suggesting high clay content alone is not a proximal limitation on AGB. Understanding how fire and herbivory contribute to AGB heterogeneity is critical to predicting future savanna carbon storage under a changing climate.

  5. CosmoBon, tree research team, for studying utilization of woody plant in space environment

    Science.gov (United States)

    Tomita-Yokotani, Kaori; Yamashita, Masamichi; Hashimoto, Hirofumi; Sato, Seigo; Baba, Keiichi; Chida, Yukari

    2012-07-01

    We are proposing to raise woody plants in space for several applications and plant science, as Tree research team, TRT. Trees produce excess oxygen, wooden materials for living cabin, and provide biomass for cultivating mushroom and insect as for the space agriculture. Excellent tree shapes which would be deeply related to wood formation improve quality of life under stressful environment in outer space. We have the serious problem about their size. Bonsai is one of the Japanese traditional arts. We have been investigating the tension wood formation under exotic gravitational environment using Bonsai. CosmoBon is the small tree Bonsai for our space experiment. The tension wood formation in CosmoBon was confirmed as the same as that in the natural trees. Our goal is to examine feasibility to grow various species of trees in space as bioresource for space agriculture.

  6. Plant biodiversity changes in Carboniferous tropical wetlands

    DEFF Research Database (Denmark)

    Cleal, C. J.; Uhl, D.; Cascales-Miñana, B.

    2012-01-01

    and Sydney coal basins. In all cases, species richness expansion followed an essentially logistic curve typical of that associated with ecologically closed habitats, with niche saturation being achieved in about three million years. The resulting steady-state (“climax”) coal swamp vegetation had a local......Using a combination of species richness, polycohort and constrained cluster analyses, the plant biodiversity of Pennsylvanian (late Carboniferous) tropical wetlands (“coal swamps”) has been investigated in five areas in Western Europe and eastern North America: South Wales, Pennines, Ruhr, Saarland...

  7. Stable isotopic variation in tropical forest plants for applications in primatology.

    Science.gov (United States)

    Blumenthal, Scott A; Rothman, Jessica M; Chritz, Kendra L; Cerling, Thure E

    2016-10-01

    Stable isotope analysis is a promising tool for investigating primate ecology although nuanced ecological applications remain challenging, in part due to the complex nature of isotopic variability in plant-animal systems. The aim of this study is to investigate sources of carbon and nitrogen isotopic variation at the base of primate food webs that reflect aspects of primate ecology. The majority of primates inhabit tropical forest ecosystems, which are dominated by C3 vegetation. We used stable isotope ratios in plants from Kibale National Park, Uganda, a well-studied closed-canopy tropical forest, to investigate sources of isotopic variation among C3 plants related to canopy stratification, leaf age, and plant part. Unpredictably, our results demonstrate that vertical stratification within the canopy does not explain carbon or nitrogen isotopic variation in leaves. Leaf age can be a significant source of isotopic variation, although the direction and magnitude of this difference is not consistent across tree species. Some plant parts are clearly differentiated in carbon and nitrogen isotopic composition, particularly leaves compared to non-photosynthetic parts such as reproductive parts and woody stem parts. Overall, variation in the isotopic composition of floral communities, plant species, and plant parts demonstrates that stable isotope studies must include analysis of local plant species and parts consumed by the primates under study from within the study area. Am. J. Primatol. 78:1041-1054, 2016. © 2015 Wiley Periodicals, Inc. © 2015 Wiley Periodicals, Inc.

  8. Efficiency of producing anion and relative humidity of the indigenous woody plants in Jeju islands

    Science.gov (United States)

    Son, S.-G.; Kim, K.-J.; Kim, H.-J.; Kim, C.-M.; Byun, K.-O.

    2009-04-01

    This study is to evaluate the ability of interior plants to produce anion and relative humidity that can purify polluted indoor air. Four indigenous woody plants in Jeju islands such as Sarcandra glaber (Thunb.) Nakai, Illicium anisatum L, Cleyera japonica Thunb. and Ilex rotunda Thunb. were used. Sansevieria trifasciata cv. Laurentii was also used as a comparative plant. The amount of anion and increment of relative humidity produced by five species of indoor plants was assessed by anion measurement (ITC-201A)in a sealed acryl chamber (118Ã-118Ã-119.5cm). The highest amount of anion was 515 ea/cm3produced by I. rotunda. The amounts of anion were 293 ea/cm3, 273 ea/cm3, and 211 ea/cm3 in S. glaber, I. anisatum and C. japonica, respecively while it was 220 ea/cm3 in S. trifasciata. The increment of relative humidity was highest in I. anisatum as 27.4% while it was lowest in S. trifasciata as 14.0%. This result suggested that all four indigenous plants tested were more effective to purify the indoor polluted air than S. trifasciata. Key words: interior plant, S. glaber, I. anisatum, C. japonica, I. rotunda, indoor polluted air

  9. Vegetation types, dominant compositions, woody plant diversity and stand structure in Trishna Wildlife Sanctuary of Northeast India.

    Science.gov (United States)

    Majumdar, Koushik; Datta, B K

    2015-03-01

    Present study was carried out to assess the vegetation types, diversity and phytosociological status of woody plants in Trishna Wildlife Sanctuary of Tripura, Northeast India. Vegetation data was derived by 25 line transects (10 m wide and 500 m length, each 0.5 ha size). All woody species at >10 cm gbh (Girth at Breast Height) within each plots were measured and counted. A total of six forest types were classified by cluster analysis using Importance Value Index (IVI) of 289 woody species. Species diversity, forest structure and woody community associations were evaluated and discussed. One way ANOVA revealed significant differences in all species diversity measures and stand structure along the forest types. Distribution of stem density at ten different gbh classes showed reverse J-shaped curves. Population status of woody plants was also examined through grouping of all individuals into four population age stages viz. sapling ( or = 30 - 120 - 210 cm gbh) and old (> or =210 cm). To observe dominant composition and species population trend, IVI of top ten dominant species from all forest types were tabulated. The present study suggested that Trishna Wildlife Sanctuary is an important habitat in Tripura from floristic point of view and it should be conserved on priority basis for remaining wildlife endurances and monitor for forest livelihoods products for sustainable biodiversity conservation in this region.

  10. Herbivores shape woody plant communities in the Kruger National Park: Lessons from three long-term exclosures

    Directory of Open Access Journals (Sweden)

    Benjamin J. Wigley

    2014-03-01

    Full Text Available The role of grazers in determining vegetation community compositions and structuring plant communities is well recognised in grassy systems. The role of browsers in affecting savanna woody plant communities is less clear. We used three long-term exclosures in the Kruger National Park to determine the effect of browsers on species compositions and population structures of woody communities. Species assemblages, plant traits relating to browsing and soil nutrients were compared inside and outside of the exclosures. Our results showed that browsers directly impact plant species distributions, densities and population structures by actively selecting for species with traits which make them desirable to browsers. Species with high leaf nitrogen, low total phenolic content and low acid detergent lignin appeared to be favoured by herbivores and therefore tend to be rare outside of the exclosures. This study also suggested that browsers have important indirect effects on savanna functioning, as the reduction of woody cover can result in less litter of lower quality, which in turn can result in lower soil fertility. However, the magnitude of browser effects appeared to depend on inherent soil fertility and climate. Conservation implications: Browsers were shown to have significant impacts on plant communities. They have noticeable effects on local species diversity and population structure, as well as soil nutrients. These impacts are shown to be related to the underlying geology and climate. The effects of browsers on woody communities were shown to be greater in low rainfall, fertile areas compared to high rainfall, infertile soils.

  11. Direct effects of warming increase woody plant abundance in a subarctic wetland.

    Science.gov (United States)

    Carlson, Lindsay G; Beard, Karen H; Adler, Peter B

    2018-03-01

    Both the direct effects of warming on a species' vital rates and indirect effects of warming caused by interactions with neighboring species can influence plant populations. Furthermore, herbivory mediates the effects of warming on plant community composition in many systems. Thus, determining the importance of direct and indirect effects of warming, while considering the role of herbivory, can help predict long-term plant community dynamics. We conducted a field experiment in the coastal wetlands of western Alaska to investigate how warming and herbivory influence the interactions and abundances of two common plant species, a sedge, Carex ramenskii , and a dwarf shrub, Salix ovalifolia . We used results from the experiment to model the equilibrium abundances of the species under different warming and grazing scenarios and to determine the contribution of direct and indirect effects to predict population changes. Consistent with the current composition of the landscape, model predictions suggest that Carex is more abundant than Salix under ambient temperatures with grazing (53% and 27% cover, respectively). However, with warming and grazing, Salix becomes more abundant than Carex (57% and 41% cover, respectively), reflecting both a negative response of Carex and a positive response of Salix to warming. While grazing reduced the cover of both species, herbivory did not prevent a shift in dominance from sedges to the dwarf shrub. Direct effects of climate change explained about 97% of the total predicted change in species cover, whereas indirect effects explained only 3% of the predicted change. Thus, indirect effects, mediated by interactions between Carex and Salix, were negligible, likely due to use of different niches and weak interspecific interactions. Results suggest that a 2°C increase could cause a shift in dominance from sedges to woody plants on the coast of western Alaska over decadal timescales, and this shift was largely a result of the direct effects

  12. Underexploited tropical plants with promising economic value

    Energy Technology Data Exchange (ETDEWEB)

    1975-01-01

    The apparent advantages of staple plants over the minor tropical plants often result only from the disproportionate research attention they have been given. A world-wide inquiry resulted in a list of 400 promising but neglected species. The 36 most important species are described in compact monographs and concern cereals (Echinochloa turnerana, grain amaranths, quinua and Zosterea mazina), roots and tubers (Arrachacha, cocoyams and taro), vegetables (chaya, hearts of palms, wax gourd, winged bean), fruits (durian, mangosteen, naranjilla, pejibaye, pummelo, soursop, uvilla), oilseeds (babassu palm, buffalo gourd, Caryocar species, Hessenia polycarpa and jojoba), forage (Acacia albida, Brosimum alicastrum Cassia sturtii, saltbushes and tamarugo) and other crops (buriti palm, Calathea lutea, candelilla, guar, guayule, Paspalum vaginatum, ramie and Spirulina).

  13. On the issue of drought-tolerant ornamental woody plants the Black Sea coast (near Sochi

    Directory of Open Access Journals (Sweden)

    Karpun Yuriy Nikolaevich

    2017-12-01

    Full Text Available The summer-autumn drought, when rainfall in July - September, less than 200 mm, a significant limiting factor for ornamental woody plants of the Black Sea coast of the Caucasus. In the region under dry periods are irregular, the study of their impact on plants is problematic and delayed for many years. The last drought was in 2015, when the three months fell only 87 mm of rainfall. In the last days of the dry period were examined 501 views and intraspecific taxa belonging to 112 genera, bushy evergreen shrubs and trees, as the most vulnerable. Evaluation of drought resistance was evaluated according to our 3-point system, and the results were analyzed in the context of consolidated floristic regions. The results showed adequate drought tolerance, not less than 65 %, cultivated in the region of evergreen shrubs and bushy trees mainly from East Asia and the Mediterranean. Among the species that are recommended for mass plantings, for the pre-emptive use of landscaping and street-resistant plants 67-80 %. All this ensures stability and high decorative plants ofSochi city.

  14. Electrophysiological assessment of water stress in fruit-bearing woody plants.

    Science.gov (United States)

    Ríos-Rojas, Liliana; Tapia, Franco; Gurovich, Luis A

    2014-06-15

    Development and evaluation of a real-time plant water stress sensor, based on the electrophysiological behavior of fruit-bearing woody plants is presented. Continuous electric potentials are measured in tree trunks for different irrigation schedules, inducing variable water stress conditions; results are discussed in relation to soil water content and micro-atmospheric evaporative demand, determined continuously by conventional sensors, correlating this information with tree electric potential measurements. Systematic and differentiable patterns of electric potentials for water-stressed and no-stressed trees in 2 fruit species are presented. Early detection and recovery dynamics of water stress conditions can also be monitored with these electrophysiology sensors, which enable continuous and non-destructive measurements for efficient irrigation scheduling throughout the year. The experiment is developed under controlled conditions, in Faraday cages located at a greenhouse area, both in Persea americana and Prunus domestica plants. Soil moisture evolution is controlled using capacitance sensors and solar radiation, temperature, relative humidity, wind intensity and direction are continuously registered with accurate weather sensors, in a micro-agrometeorological automatic station located at the experimental site. The electrophysiological sensor has two stainless steel electrodes (measuring/reference), inserted on the stem; a high precision Keithley 2701 digital multimeter is used to measure plant electrical signals; an algorithm written in MatLab(®), allows correlating the signal to environmental variables. An electric cyclic behavior is observed (circadian cycle) in the experimental plants. For non-irrigated plants, the electrical signal shows a time positive slope and then, a negative slope after restarting irrigation throughout a rather extended recovery process, before reaching a stable electrical signal with zero slope. Well-watered plants presented a

  15. Modifying woody plants for efficient conversion to liquid and gaseous fuels

    Energy Technology Data Exchange (ETDEWEB)

    Dinus, R.J.; Dimmel, D.R.; Feirer, R.P.; Johnson, M.A.; Malcolm, E.W. (Institute of Paper Science and Technology, Atlanta, GA (USA))

    1990-07-01

    The Short Rotation Woody Crop Program (SRWCP), Department of Energy, is developing woody plant species as sources of renewable energy. Much progress has been made in identifying useful species, and testing site adaptability, stand densities, coppicing abilities, rotation lengths, and harvesting systems. Conventional plant breeding and intensive cultural practices have been used to increase above-ground biomass yields. Given these and foreseeable accomplishments, program leaders are now shifting attention to prospects for altering biomass physical and chemical characteristics, and to ways for improving the efficiency with which biomass can be converted to gaseous and liquid fuels. This report provides a review and synthesis of literature concerning the quantity and quality of such characteristics and constituents, and opportunities for manipulating them via conventional selection and breeding and/or molecular biology. Species now used by SRWCP are emphasized, with supporting information drawn from others as needed. Little information was found on silver maple (Acer saccharinum), but general comparisons (Isenberg 1981) suggest composition and behavior similar to those of the other species. Where possible, conclusions concerning means for and feasibility of manipulation are given, along with expected impacts on conversion efficiency. Information is also provided on relationships to other traits, genotype X environment interactions, and potential trade-offs or limitations. Biomass productivity per se is not addressed, except in terms of effects that may by caused by changes in constituent quality and/or quantity. Such effects are noted to the extent they are known or can be estimated. Likely impacts of changes, however effected, on suitability or other uses, e.g., pulp and paper manufacture, are notes. 311 refs., 4 figs., 9 tabs.

  16. Symbiosis with AMF and leaf Pi supply increases water deficit tolerance of woody species from seasonal dry tropical forest.

    Science.gov (United States)

    Frosi, Gabriella; Barros, Vanessa A; Oliveira, Marciel T; Santos, Mariana; Ramos, Diego G; Maia, Leonor C; Santos, Mauro G

    2016-12-01

    In seasonal dry tropical forests, plants are subjected to severe water deficit, and the arbuscular mycorrhizal fungi (AMF) or inorganic phosphorus supply (P i ) can mitigate the effects of water deficit. This study aimed to assess the physiological performance of Poincianella pyramidalis subjected to water deficit in combination with arbuscular mycorrhizal fungi (AMF) and leaf inorganic phosphorus (P i ) supply. The experiment was conducted in a factorial arrangement of 2 water levels (+H 2 O and -H 2 O), 2 AMF levels (+AMF and -AMF) and 2P i levels (+P i and -P i ). Leaf primary metabolism, dry shoot biomass and leaf mineral nutrients were evaluated. Inoculated AMF plants under well-watered and drought conditions had higher photosynthesis and higher shoot biomass. Under drought, AMF, P i or AMF+P i plants showed metabolic improvements in photosynthesis, leaf biochemistry and higher biomass compared to the plants under water deficit without AMF or P i . After rehydration, those plants submitted to drought with AMF, P i or AMF+P i showed a faster recovery of photosynthesis compared to treatment under water deficit without AMF or P i . However, plants under the drought condition with AMF showed a higher net photosynthesis rate. These findings suggest that AMF, P i or AMF+P i increase the drought tolerance in P. pyramidalis, and AMF associations under well-watered conditions increase shoot biomass and, under drought, promoted faster recovery of photosynthesis. Copyright © 2016 Elsevier GmbH. All rights reserved.

  17. Large-scale carbon stock assessment of woody vegetation in tropical dry deciduous forest of Sathanur reserve forest, Eastern Ghats, India.

    Science.gov (United States)

    Gandhi, Durai Sanjay; Sundarapandian, Somaiah

    2017-04-01

    Tropical dry forests are one of the most widely distributed ecosystems in tropics, which remain neglected in research, especially in the Eastern Ghats. Therefore, the present study was aimed to quantify the carbon storage in woody vegetation (trees and lianas) on large scale (30, 1 ha plots) in the dry deciduous forest of Sathanur reserve forest of Eastern Ghats. Biomass of adult (≥10 cm DBH) trees was estimated by species-specific allometric equations using diameter and wood density of species whereas in juvenile tree population and lianas, their respective general allometric equations were used to estimate the biomass. The fractional value 0.4453 was used to convert dry biomass into carbon in woody vegetation of tropical dry forest. The mean aboveground biomass value of juvenile tree population was 1.86 Mg/ha. The aboveground biomass of adult trees ranged from 64.81 to 624.96 Mg/ha with a mean of 245.90 Mg/ha. The mean aboveground biomass value of lianas was 7.98 Mg/ha. The total biomass of woody vegetation (adult trees + juvenile population of trees + lianas) ranged from 85.02 to 723.46 Mg/ha, with a mean value of 295.04 Mg/ha. Total carbon accumulated in woody vegetation in tropical dry deciduous forest ranged from 37.86 to 322.16 Mg/ha with a mean value of 131.38 Mg/ha. Adult trees accumulated 94.81% of woody biomass carbon followed by lianas (3.99%) and juvenile population of trees (1.20%). Albizia amara has the greatest biomass and carbon stock (58.31%) among trees except for two plots (24 and 25) where Chloroxylon swietenia contributed more to biomass and carbon stock. Similarly, Albizia amara (52.4%) showed greater carbon storage in juvenile population of trees followed by Chloroxylon swietenia (21.9%). Pterolobium hexapetalum (38.86%) showed a greater accumulation of carbon in liana species followed by Combretum albidum (33.04%). Even though, all the study plots are located within 10 km radius, they show a significant spatial variation among

  18. On eradication of woody plants with herbicides in fields and pastures

    Directory of Open Access Journals (Sweden)

    Jaakko Mukula

    1950-01-01

    Full Text Available On the initiative of the Department of Plant Husbandry of Agricultural Research Institute, experiments for destroying woody plants on fields and pastures were conducted in 1948—1949 with the following chemicals: Artificial hormones (sodium salt of 2,4-D, morpholine of 2,4-D, triethanolamine of 2,4-D, ethyl ester of 2,4-D, butyl ester of 2,4-D, and sodium salt of 2M-4K, potassium chlorate, and ammonium salt of dinitro-ortochresol. The substances Were applied in aqueous solutions, or as emulsions. Three different methods Were used: spray application to foliage, absorption through a cut branch, and application to soil. The following thicket-forming woody plants, common in Finland, were investigated: grey alder, Alnus incana (L. Willd., willow, Salix sp., birch, Betula sp., mountain ash, Sorbus aucuparia L., and aspen, Populus tremula L. Following conclusions have been drawn from the experiments; It is possible, and, probably with the exception of aspen, even advisable to destroy small sprouts, 0.5—1.5 m. in height, of these woody plants by spraying their foliage with artificial hormones early in summer, especially if mechanical clearing machines cannot be used. Of the experimented substances, esters of 2,4-D proved the most effective in spray applications, but satisfactory results were even secured with other artificial hormones. For different species of woody plants the necessary concentration of the solution varies from 0.1 to 0.4 % of the active substance (p. 6. For dense thickets, 0.5—1.5 m. in height, the amount of solution used Was 1250—2000 l. per ha., applied by means of knapsack type of pressure sprayers. All branches must be sprayed. It is difficult to make the treatment effective enough, if only one application is made. Therefore it is important to conduct a new control spraying after 2—3 weeks. Treatment is most effective, if given in Warm, sunny weather. The best results are secured with spraying towards the end of June or at

  19. Regulation of Light Energy Utilization and Distribution of Photosynthesis in Five Subtropical Woody Plants

    Institute of Scientific and Technical Information of China (English)

    Nan Liu; Chang-Lian Peng; Zhi-Fang Lin; Gui-Zhu Lin; Xiao-Ping Pan

    2007-01-01

    The adaptations and responses of photosynthesis to long- and short-term growth light gradient treatments were investigated in five subtropical forest plants, namely Pinus massoniana Lamb., Schima superba Gardn. et Champ.,Castanopsis fissa (Champ. ex Benth.) Rehd. et Wils., Acmena acuminatissima (BI.) Merr et Perry, and Cryptocarya concinna Hance. With diurnal changes in sunlight and air temperature, the de-epoxidation state and lutein content in the five woody plants under three light intensifies first increased and then decreased during the day. However,maximal photochemical efficiency (Fv/Fm; where Fm is the maximum fluorescence yield and Fv is variable fluorescence) and the photochemical quantum yields of photosystem (PS) Ⅱ (ΦPSII) of the species examined changed in the opposite manner, with those in plants grown under 100% natural light changing the most. After long-term treatment (21 months), anti-oxidant capacity (1,1-diphenyl-2-picrylhydrazyl radical (DPPH·)-scavenging capacity) and utilization of excitation energy showed differences in modulation by different light intensities. It was shown that A.acuminatissima and C. concinna, as dominant species in the late succession stage of a subtropical forest in Dinghu mountain, South China, were better able to adapt to different light environments. However, P. massoniana, the pioneer species of this forest, exhibited less adaptation to Iow light intensity and was definitely eliminated by the forest successlon process.

  20. Microbial activity, arbuscular mycorrhizal fungi and inoculation of woody plants in lead contaminated soil

    Directory of Open Access Journals (Sweden)

    Graziella S Gattai

    2011-09-01

    Full Text Available The goals of this study were to evaluate the microbial activity, arbuscular mycorrhizal fungi and inoculation of woody plants (Caesalpinia ferrea, Mimosa tenuiflora and Erythrina velutina in lead contaminated soil from the semi-arid region of northeastern of Brazil (Belo Jardim, Pernambuco. Dilutions were prepared by adding lead contaminated soil (270 mg Kg-1 to uncontaminated soil (37 mg Pb Kg soil-1 in the proportions of 7.5%, 15%, and 30% (v:v. The increase of lead contamination in the soil negatively influenced the amount of carbon in the microbial biomass of the samples from both the dry and rainy seasons and the metabolic quotient only differed between the collection seasons in the 30% contaminated soil. The average value of the acid phosphatase activity in the dry season was 2.3 times higher than observed during the rainy season. There was no significant difference in the number of glomerospores observed between soils and periods studied. The most probable number of infective propagules was reduced for both seasons due to the excess lead in soil. The mycorrhizal colonization rate was reduced for the three plant species assayed. The inoculation with arbuscular mycorrhizal fungi benefited the growth of Erythrina velutina in lead contaminated soil.

  1. The complete chloroplast genome sequence of the relict woody plant Metasequoia glyptostroboides Hu et Cheng

    Directory of Open Access Journals (Sweden)

    Jinhui eChen

    2015-06-01

    Full Text Available Metasequoia glyptostroboides Hu et Cheng is the only species in the genus Metasequoia Miki ex Hu et Cheng, which belongs to the Cupressaceae family. There were around ten species in the Metasequoia genus, which were widely spread across the Northern Hemisphere during the Cretaceous of the Mesozoic and in the Cenozoic. M. glyptostroboides is the only remaining representative of this genus. Here, we report the complete chloroplast (cp genome sequence and the cp genomic features of M. glyptostroboides. The M. glyptostroboides cp genome is 131,887 bp in length, with a total of 117 genes comprised of 82 protein-coding genes, 31 tRNA genes and four rRNA genes. In this genome, 11 forward repeats, nine palindromic repeats and 15 tandem repeats were detected. A total of 188 perfect microsatellites were detected through simple sequence repeat (SSR analysis and these were distributed unevenly within the cp genome. Comparison of the cp genome structure and gene order to those of several other land plants indicated that a copy of the inverted repeat (IR region, which was found to be IR region A (IRA, was lost in the M. glyptostroboides cp ge-nome. The five most divergent and five most conserved genes were determined and further phylogenetic analysis was performed among plant species, especially for relat-ed species in conifers. Finally, phylogenetic analysis demonstrated that M. glyptostro-boides is a sister species to Cryptomeria japonica (L. F. D. Don and to Taiwania cryptomerioides Hayata. The complete cp genome sequence information of M. glyp-tostroboides will be great helpful for further investigations of this endemic relict woody plant and for in-depth understanding of the evolutionary history of the conif-erous cp genomes, especially for the position of M. glyptostroboides in plant systemat-ics and evolution.

  2. The complete chloroplast genome sequence of the relict woody plant Metasequoia glyptostroboides Hu et Cheng.

    Science.gov (United States)

    Chen, Jinhui; Hao, Zhaodong; Xu, Haibin; Yang, Liming; Liu, Guangxin; Sheng, Yu; Zheng, Chen; Zheng, Weiwei; Cheng, Tielong; Shi, Jisen

    2015-01-01

    Metasequoia glyptostroboides Hu et Cheng is the only species in the genus Metasequoia Miki ex Hu et Cheng, which belongs to the Cupressaceae family. There were around 10 species in the Metasequoia genus, which were widely spread across the Northern Hemisphere during the Cretaceous of the Mesozoic and in the Cenozoic. M. glyptostroboides is the only remaining representative of this genus. Here, we report the complete chloroplast (cp) genome sequence and the cp genomic features of M. glyptostroboides. The M. glyptostroboides cp genome is 131,887 bp in length, with a total of 117 genes comprised of 82 protein-coding genes, 31 tRNA genes and four rRNA genes. In this genome, 11 forward repeats, nine palindromic repeats, and 15 tandem repeats were detected. A total of 188 perfect microsatellites were detected through simple sequence repeat (SSR) analysis and these were distributed unevenly within the cp genome. Comparison of the cp genome structure and gene order to those of several other land plants indicated that a copy of the inverted repeat (IR) region, which was found to be IR region A (IRA), was lost in the M. glyptostroboides cp genome. The five most divergent and five most conserved genes were determined and further phylogenetic analysis was performed among plant species, especially for related species in conifers. Finally, phylogenetic analysis demonstrated that M. glyptostroboides is a sister species to Cryptomeria japonica (L. F.) D. Don and to Taiwania cryptomerioides Hayata. The complete cp genome sequence information of M. glyptostroboides will be great helpful for further investigations of this endemic relict woody plant and for in-depth understanding of the evolutionary history of the coniferous cp genomes, especially for the position of M. glyptostroboides in plant systematics and evolution.

  3. Controls upon microbial accessibility to soil organic matter following woody plant encroachment into grasslands

    Science.gov (United States)

    Creamer, C. A.; Boutton, T. W.; Filley, T. R.

    2009-12-01

    Woody plant encroachment (WPE) into savannas and grasslands is a global phenomenon that alters soil organic matter (SOM) dynamics through changes in litter quality and quantity, soil structure, microbial ecology, and soil hydrology. To elucidate the controls upon microbial accessibility to SOM, bulk soils from a chronosequence of progressive WPE into native grasslands at the Texas A&M Agricultural Experimental Station La Copita Research Area were incubated for one year. The quantity and stable carbon isotope composition of respired CO2, plant biopolymer chemistry in SOM, and microbial community structure were tracked. Respiration rates declined steadily over the course of the experiment with 15-25% of the total CO2 respired released in the first month of incubation. Between 8 and 18% of the total carbon was mineralized to CO2 throughout the incubation. After day 84 a significantly (p evidence of enhanced carbon stabilization in these respiration experiments. In fact, a greater proportion of total carbon was lost from the soil of mature woody stands than from young stands, suggesting carbon accumulation observed with WPE may be due to greater input rates or microbial dynamics not captured in the laboratory incubation. A cluster approximately 34 years in age represents a transition point in WPE where respiration dynamics become distinct between grassland and wooded elements. By day 84 of the incubation CO2 respired from all soils was depleted with respect to bulk SOM (1.5 to 5‰) and this pattern remained for the rest of the incubation. As the depletion of CO2 relative to bulk SOM was observed in grassland and cluster soils, we hypothesized the depleted signature resulted from the utilization of depleted biopolymers, specifically lignin, cutin and suberin, as hypothesized by others. Quantitative and isotopic comparisons of these monomers prior to and following the incubation will determine if selective compound utilization is a reason for this depletion. The results

  4. Isolation of high quality RNA from pistachio (Pistacia vera L.) and other woody plants high in secondary metabolites.

    Science.gov (United States)

    Moazzam Jazi, Maryam; Rajaei, Saideh; Seyedi, Seyed Mahdi

    2015-10-01

    The quality and quantity of RNA are critical for successful downstream transcriptome-based studies such as microarrays and RNA sequencing (RNA-Seq). RNA isolation from woody plants, such as Pistacia vera, with very high amounts of polyphenols and polysaccharides is an enormous challenge. Here, we describe a highly efficient protocol that overcomes the limitations posed by poor quality and low yield of isolated RNA from pistachio and various recalcitrant woody plants. The key factors that resulted in a yield of 150 μg of high quality RNA per 200 mg of plant tissue include the elimination of phenol from the extraction buffer, raising the concentration of β-mercaptoethanol, long time incubation at 65 °C, and nucleic acid precipitation with optimized volume of NaCl and isopropyl alcohol. Also, the A260/A280 and A260/A230 of extracted RNA were about 1.9-2.1and 2.2-2.3, respectively, revealing the high purity. Since the isolated RNA passed highly stringent quality control standards for sensitive reactions, including RNA sequencing and real-time PCR, it can be considered as a reliable and cost-effective method for RNA extraction from woody plants.

  5. Individual species-area relationship of woody plant communities in a heterogeneous subtropical monsoon rainforest.

    Science.gov (United States)

    Tsai, Cheng-Han; Lin, Yi-Ching; Wiegand, Thorsten; Nakazawa, Takefumi; Su, Sheng-Hsin; Hsieh, Chih-Hao; Ding, Tzung-Su

    2015-01-01

    The spatial structure of species richness is often characterized by the species-area relationship (SAR). However, the SAR approach rarely considers the spatial variability of individual plants that arises from species interactions and species' habitat associations. Here, we explored how the interactions of individual plants of target species influence SAR patterns at a range of neighborhood distances. We analyzed the data of 113,988 woody plants of 110 species from the Fushan Forest Dynamics Plot (25 ha), northern Taiwan, which is a subtropical rainforest heavily influenced by typhoons. We classified 34 dominant species into 3 species types (i.e., accumulator, repeller, or no effect) by testing how the individual species-area relationship (i.e., statistics describing how neighborhood species richness changes around individuals) of target species departs (i.e., positively, negatively, or with no obvious trend) from a null model that accounts for habitat association. Deviation from the null model suggests that the net effect of species' interactions increases (accumulate) or decreases (repel) neighborhood species richness. We found that (i) accumulators were dominant at small interaction distances (30 m); (iii) repellers were rarely detected; and (iv) large-sized and abundant species tended to be accumulators. The findings suggest that positive species interactions have the potential to accumulate neighborhood species richness, particularly through size- and density-dependent mechanisms. We hypothesized that the frequently disturbed environment of this subtropical rainforest (e.g., typhoon-driven natural disturbances such as landslides, soil erosion, flooding, and windthrow) might create the spatial heterogeneity of species richness and promote positive species interactions.

  6. Loss of native herbaceous species due to woody plant encroachment facilitates the establishment of an invasive grass.

    Science.gov (United States)

    Alofs, Karen M; Fowler, Norma L

    2013-03-01

    Although negative relationships between diversity (frequently measured as species richness) and invasibility at neighborhood or community scales have often been reported, realistic natural diversity gradients have rarely been studied at this scale. We recreated a naturally occurring gradient in species richness to test the effects of species richness on community invasibility. In central Texas savannas, as the proportion of woody plants increases (a process known as woody plant encroachment), herbaceous habitat is both lost and fragmented, and native herbaceous species richness declines. We examined the effects of these species losses on invasibility in situ by removing species that occur less frequently in herbaceous patches as woody plant encroachment advances. This realistic species removal was accompanied by a parallel and equivalent removal of biomass with no changes in species richness. Over two springs, the nonnative bunchgrass Bothriochloa ischaemum germinated significantly more often in the biomass-removal treatment than in unmanipulated control plots, suggesting an effect of native plant density independent of diversity. Additionally, significantly more germination occurred in the species-removal treatment than in the biomass-removal treatment. Changes in species richness had a stronger effect on B. ischaemum germination than changes in plant density, demonstrating that niche-related processes contributed more to biotic resistance in this system than did species-neutral competitive interactions. Similar treatment effects were found on transplant growth. Thus we show that woody plant encroachment indirectly facilitates the establishment of an invasive grass by reducing native diversity. Although we found a negative relationship between species richness and invasibility at the scale of plots with similar composition and environmental conditions, we found a positive relationship between species richness and invasibility at larger scales. This apparent

  7. Climate change and future overwintering conditions of horticultural woody-plants in Finland

    Energy Technology Data Exchange (ETDEWEB)

    Laapas, M.; Jylhae, K.; Tuomenvirta, H. (Finnish Meteorological Inst., Helsinki (Finland))

    2012-07-01

    Climate in Finland offers challenging conditions for commercial horticulture. The short and insufficient growing season together with risky overwintering strongly limits species suitable for cultivation. The aim of this study was to examine the climatic conditions around Finland in the aspect of horticulture, focusing on processes relevant to woody plants and species with photoperiod controlled growth cessation, and how these conditions may be expected to change due to the projected global warming. For this, a set of temperature-related indices and threshold events were used. These indices represent the severity of coldness during winter, wintertime thaws, and frost events close to the onset and ending of the growing season. The combined results of 19 GCMs (General Circulation Model) from the CMIP3 (Coupled Model Intercomparison Project 3) multi-model data set under SRES-B1 and SRES-A2 (Special Report on Emission Scenarios) emission scenarios were used to produce the future projections. By mid-century our results suggest wintertime conditions with reduced cold stress, caused by less frequent and shorter periods of severe frost together with a rise in the extreme minimum temperature. Conversely, an increase in the number and intensity of wintertime thaw events leads to a higher risk in overwintering. Also the risk of spring frost damage is projected to decrease slightly, and the conditions for cold hardening process to improve, as the first autumnal frosts occur later. (orig.)

  8. Phytosanitary inspection of woody plants for planting at european union entry points: A practical enquiry

    OpenAIRE

    Eschen, René; Rigaux, Ludovic; Sukovata, Lidia; Vettraino, Anna Maria; Marzano, Mariella; Grégoire, Jean-Claude

    2015-01-01

    Phytosanitary import inspections are important to avoid entry of harmful pests on live plants. In the European Union (EU), all consignments of live plants must be inspected at the first point of entry, and plants allowed entry can be moved without further inspection among the 28 Member States and Switzerland. It is important that inspections in EU countries adhere to the same standard to avoid introduction of harmful organisms through countries with weaker methods. We tested whether sampling ...

  9. Meta-analysis of susceptibility of woody plants to loss of genetic diversity through habitat fragmentation.

    Science.gov (United States)

    Vranckx, Guy; Jacquemyn, Hans; Muys, Bart; Honnay, Olivier

    2012-04-01

    Shrubs and trees are assumed less likely to lose genetic variation in response to habitat fragmentation because they have certain life-history characteristics such as long lifespans and extensive pollen flow. To test this assumption, we conducted a meta-analysis with data on 97 woody plant species derived from 98 studies of habitat fragmentation. We measured the weighted response of four different measures of population-level genetic diversity to habitat fragmentation with Hedge's d and Spearman rank correlation. We tested whether the genetic response to habitat fragmentation was mediated by life-history traits (longevity, pollination mode, and seed dispersal vector) and study characteristics (genetic marker and plant material used). For both tests of effect size habitat fragmentation was associated with a substantial decrease in expected heterozygosity, number of alleles, and percentage of polymorphic loci, whereas the population inbreeding coefficient was not associated with these measures. The largest proportion of variation among effect sizes was explained by pollination mechanism and by the age of the tissue (progeny or adult) that was genotyped. Our primary finding was that wind-pollinated trees and shrubs appeared to be as likely to lose genetic variation as insect-pollinated species, indicating that severe habitat fragmentation may lead to pollen limitation and limited gene flow. In comparison with results of previous meta-analyses on mainly herbaceous species, we found trees and shrubs were as likely to have negative genetic responses to habitat fragmentation as herbaceous species. We also found that the genetic variation in offspring was generally less than that of adult trees, which is evidence of a genetic extinction debt and probably reflects the genetic diversity of the historical, less-fragmented landscape. ©2011 Society for Conservation Biology.

  10. The phyllophagous of woody plants of genus Ulmus in protective plantings of arid zone

    Science.gov (United States)

    Belitskaya, M. N.; Gribust, I. R.; Nefed'eva, E. E.; Filimonova, O. S.; Golovanova, M. A.

    2018-01-01

    Creating of long-lasting, normally developing plantings on the urbanized territories in the arid zones is difficult. The main tree species are elm (Fam. Ulmaceae - more than 70% of tree composition). They have a high drought and salt tolerance, rapid growth. They are widely used in the creation of artificial forest plantings in steppes and deserts. The main part of the plantations was created in the 50-60 years of 20th century. Today the aging of plants is observing. Trees of this age lose their physiological and decorative potential as well as resistance to pests under intensive anthropogenic impact. At the forest pathology research about 90 % of the plants of elm species of plantings of various types and categories were identified to be in poor condition. Leaf-eating pests play an active role in the deterioration of their sanitary state. Xanthogaleruca luteola (Müller, 1766), Cladius ulmi (Linnaeus, 1758), and Aproceros leucopoda (Takeuchi, 1939) have a special harmfulness as well as the regularity of the local centers among the mass phyllophagous of plants of the family. The last two species were discovered in artificial plantations for the first time. The destructive effect of those pests on certain types of elm plants is uneven.

  11. Forest Distribution on Small Isolated Hills and Implications on Woody Plant Distribution under Threats of Global Warming

    Directory of Open Access Journals (Sweden)

    Chi-Cheng Liao

    2012-09-01

    Full Text Available Treelines have been found to be lower in small isolated hilltops, but the specific dynamics behind this unique phenomenon are unknown. This study investigates the distribution patterns of woody plants in Yangmingshan National Park (YMSNP, Northern Taiwan in search of the limitation mechanisms unique to small isolated hills, and to evaluate potential threats under global warming. Forests distributed between 200 to 900 m above sea level (ASL. Remnant forest fragments between 400 and 900 m ASL, have the highest species richness, and should be protected to ensure future forest recovery from the former extensive artificial disturbance. The lower boundary is threatened by urban and agricultural development. The lack of native woody species in these low elevation zones may cause a gap susceptible to invasive species. A consistent forest line at 100 m below mountain tops regardless of elevation suggests a topography-induced instead of an elevation-related limiting mechanism. Therefore, upward-shift of forests, caused by global warming, might be limited at 100 m below hilltops in small isolated hills because of topography-related factors. The spatial range of woody plants along the altitudinal gradient, thus, is likely to become narrower under the combined pressures of global warming, limited elevation, exposure-related stress, and artificial disturbance. Management priorities for forest recovery are suggested to include preservation of remnant forest fragments, increasing forest connectivity, and increasing seedling establishment in the grasslands.

  12. Landscape Variation in Plant Defense Syndromes across a Tropical Rainforest

    Science.gov (United States)

    McManus, K. M.; Asner, G. P.; Martin, R.; Field, C. B.

    2014-12-01

    Plant defenses against herbivores shape tropical rainforest biodiversity, yet community- and landscape-scale patterns of plant defense and the phylogenetic and environmental factors that may shape them are poorly known. We measured foliar defense, growth, and longevity traits for 345 canopy trees across 84 species in a tropical rainforest and examined whether patterns of trait co-variation indicated the existence of plant defense syndromes. Using a DNA-barcode phylogeny and remote sensing and land-use data, we investigated how phylogeny and topo-edaphic properties influenced the distribution of syndromes. We found evidence for three distinct defense syndromes, characterized by rapid growth, growth compensated by defense, or limited palatability/low nutrition. Phylogenetic signal was generally lower for defense traits than traits related to growth or longevity. Individual defense syndromes were organized at different taxonomic levels and responded to different spatial-environmental gradients. The results suggest that a diverse set of tropical canopy trees converge on a limited number of strategies to secure resources and mitigate fitness losses due to herbivory, with patterns of distribution mediated by evolutionary histories and local habitat associations. Plant defense syndromes are multidimensional plant strategies, and thus are a useful means of discerning ecologically-relevant variation in highly diverse tropical rainforest communities. Scaling this approach to the landscape level, if plant defense syndromes can be distinguished in remotely-sensed data, they may yield new insights into the role of plant defense in structuring diverse tropical rainforest communities.

  13. Phytoremediation of heavy metal contaminated soil potential by woody plants on Tonglushan ancient copper spoil heap in China.

    Science.gov (United States)

    Kang, Wei; Bao, Jianguo; Zheng, Jin; Xu, Fen; Wang, Liuming

    2018-01-02

    Fast-growing metal-accumulating woody plants are considered potential candidates for phytoremediation of metals. Tonglushan mining, one of the biggest Cu production bases in China, presents an important source of the pollution of environment. The sample was collected at Tonglushan ancient copper spoil heap. The aims were to measure the content of heavy metal in the soil and woody plants and to elucidate the phytoremediation potential of the plants. The result showed that soil Cu, Cd and Pb were the main contamination, the mean contents of which were 3166.73 mg/kg, 3.66 mg/kg and 137.06 mg/kg respectively, which belonged to severe contamination. Fourteen species from 14 genera of 13 families were collected and investigated; except for Ligutrum lucidum, the other 13 woody plants species were newly recorded in this area. In addition, to assess the ability of metal accumulation of these trees, we proposed accumulation index. Data suggested that Platanus × acerilolia, Broussonetia papyrifera, Ligutrum lucidum, Viburnum awabuki, Firmiana simplex, Robina pseudoacacia, Melia azedarach and Osmanthus fragrans exhibited high accumulated capacity and strong tolerance to heavy metals. Therefore, Platanus × acerilolia and Broussonetia papyrifera can be planted in Pb contaminated areas; Viburnum awabuki, Firmiana simplex, Robina pseudoacacia and Melia azedarach are the suitable trees for Cd contaminated areas; Viburnum awabuki, Melia azedarach, Ligutrum lucidum, Firmiana simplex, Osmanthus fragrans and Robina pseudoacacia are appropriate to Cu, Pb and Cd multi-metal contaminated areas.

  14. Woody plant diversity and structure of shade-grown-coffee plantations in Northern Chiapas, Mexico

    Directory of Open Access Journals (Sweden)

    Lorena Soto-Pinto

    2001-12-01

    Full Text Available Shade-grown coffee is an agricultural system that contains some forest-like characteristics. However, structure and diversity are poorly known in shade coffee systems. In 61 coffee-growers’ plots of Chiapas, Mexico, structural variables of shade vegetation and coffee yields were measured, recording species and their use. Coffee stands had five vegetation strata. Seventy seven woody species mostly used as wood were found (mean density 371.4 trees per hectare. Ninety percent were native species (40% of the local flora, the remaining were introduced species, mainly fruit trees/shrubs. Diametric distribution resembles that of a secondary forest. Principal Coordinates Analysis grouped plots in four classes by the presence of Inga, however the majority of plots are diverse. There was no difference in equitability among groups or coffee yields. Coffee yield was 835 g clean coffee per shrub, or ca. 1668 kg ha-1. There is a significant role of shade-grown coffee as diversity refuge for woody plants and presumably associated fauna, as well as an opportunity for shade-coffee growers to participate in the new biodiversity-friendly-coffee marketEl café bajo sombra es un sistema agrícola que contiene algunas características de los bosques. Sin embargo, las características estructurales y de diversidad de la sombra del café son poco conocidas. En 61 parcelas de productores del norte de Chiapas, Mexico, se midieron variables estructurales de la vegetación de sombra y los rendimientos de café, registrando las especies y sus usos. Los cafetales presentaron cinco estratos de vegetación. Se encontraron 77 especies leñosas, la mayoría de uso maderable (densidad promedio de 371.4 árboles por hectárea. Noventa por ciento fueron especies nativas (40% de la flora local, el porcentaje restante fueron especies introducidas, principalmente árboles o arbustos frutales. La distribución diamétrica se asemeja a la distribución típica de bosques secundarios

  15. Woody encroachment over 70 years in South African savannahs: overgrazing, global change or extinction aftershock?

    Science.gov (United States)

    Stevens, Nicola; Erasmus, B F N; Archibald, S; Bond, W J

    2016-09-19

    Woody encroachment in 'open' biomes like grasslands and savannahs is occurring globally. Both local and global drivers, including elevated CO2, have been implicated in these increases. The relative importance of different processes is unresolved as there are few multi-site, multi-land-use evaluations of woody plant encroachment. We measured 70 years of woody cover changes over a 1020 km(2) area covering four land uses (commercial ranching, conservation with elephants, conservation without elephants and communal rangelands) across a rainfall gradient in South African savannahs. Different directions of woody cover change would be expected for each different land use, unless a global factor is causing the increases. Woody cover change was measured between 1940 and 2010 using the aerial photo record. Detection of woody cover from each aerial photograph was automated using eCognitions' Object-based image analysis (OBIA). Woody cover doubled in all land uses across the rainfall gradient, except in conservation areas with elephants in low-rainfall savannahs. Woody cover in 2010 in low-rainfall savannahs frequently exceeded the maximum woody cover threshold predicted for African savannahs. The results indicate that a global factor, of which elevated CO2 is the likely candidate, may be driving encroachment. Elephants in low-rainfall savannahs prevent encroachment and localized megafaunal extinction is a probable additional cause of encroachment.This article is part of the themed issue 'Tropical grassy biomes: linking ecology, human use and conservation'. © 2016 The Author(s).

  16. Nuclear power plant risk from tropical cyclones

    International Nuclear Information System (INIS)

    Gilmore, T.F.

    1991-01-01

    Tropical cyclones are considered to have a potential for contributing to the overall core-melt frequency at Turkey Point. A tropical cyclone is known to have the four main hazards associated with it: wind, tidal surge, wind-generated missiles, and precipitation. To understand the contribution to overall core-melt risk at Turkey Point, it is essential to understand the mechanisms of these hazards and their relative importance. The results are bounded by the hurricane surge scenario, where the frequency of core melt is equal to the frequency of the surge reaching 19 ft NGVD (National Geographic Vertical Datum). This could be mitigated by potential recovery actions for the tropical cyclone scenario. The probability of the storm surge reaching 19 ft NVGD is estimated to be 1 x 10 -4 . The data associated with the tropical cyclones as discussed in detail in the body of this paper are lacking in quantity and quality. By taking the conservative approach in creating the wind/frequency, wind/surge, and surge/frequency relationships, the conclusion that the results are worst case is reasonable. With this in mind, it is logical to conclude that the value of further hazard analysis to narrow down the built-in conservative margin using the existing data and technology is doubtful. Thus, a recovery approach to driving the risk level down is the most pragmatic step to be taken

  17. Effects of geographical extent on the determinants of woody plant diversity

    DEFF Research Database (Denmark)

    Wang, Zhiheng; Rahbek, Carsten; Fang, Jingyun

    2012-01-01

    the quantitative effects of geographical extent are rarely tested. Here, using distribution maps of 11,405 woody species found in China and associated environmental data to the domain, we investigated the influence of geographical extent on the determinants of species richness patterns. Our results revealed...

  18. Teores de carboidratos em órgãos lenhosos do caquizeiro em clima tropical Carbohydrate content in persimmon tree woody organs in tropical climate

    Directory of Open Access Journals (Sweden)

    Carlos Eduardo Corsato

    2008-06-01

    Full Text Available Nas fruteiras caducifólias, o metabolismo de carboidratos constitui-se no principal mecanismo que garante a sua sobrevivência no período de dormência, estando, também, relacionado ao seu potencial produtivo em safras subseqüentes. Conhecer a forma como a planta utiliza esses carboidratos durante o seu desenvolvimento é um passo importante para o entendimento das suas relações fonte-dreno e para fundamentar algumas práticas de manejo, como a poda e o raleio de frutos. Caracterizar a variação dos teores de amido e de carboidratos solúveis totais em órgãos lenhosos do caquizeiro (Diospyros kaki L., no decorrer do seu desenvolvimento fenológico, foi o objeto de investigação do presente estudo. O trabalho foi conduzido em um pomar de caquizeiros localizado na área experimental da Escola Superior de Agricultura "Luiz de Queiroz" (ESALQ, em Piracicaba, Estado de São Paulo, durante o ciclo 2002/2003. A fenologia das plantas foi caracterizada pelo período de ocorrência e duração do alongamento dos ramos, florescimento, desenvolvimento dos frutos e das folhas e do abortamento natural de frutos. A variação dos teores desses carboidratos em ramos e em raízes foi analisada tendo por base os diferentes estádios fenológicos. Ocorreram variações significativas no teor desses carboidratos no período de estudo. A mobilização do amido nos ramos teve grande importância na sustentação de um novo ciclo de brotações. O maior consumo de amido ocorreu durante a abscisão foliar, e a reposição no seu estoque, nos ramos e nas raízes ocorreu, principalmente, entre o florescimento e a abscisão foliar.In deciduous fruit trees, the carbohydrate's metabolism are recognized as the main mechanism that ensures their survival during the rest period. Besides it, the very same metabolism is related to the productive potential in subsequent harvest seasons. Knowing how the plants use those carbohydrates during their development and growth is

  19. Evaluating nurse plants for restoring native woody species to degraded subtropical woodlands

    Science.gov (United States)

    Yelenik, Stephanie G.; DiManno, Nicole; D’Antonio, Carla M.

    2015-01-01

    Harsh habitats dominated by invasive species are difficult to restore. Invasive grasses in arid environments slow succession toward more desired composition, yet grass removal exacerbates high light and temperature, making the use of “nurse plants” an appealing strategy. In this study of degraded subtropical woodlands dominated by alien grasses in Hawai'i, we evaluated whether individuals of two native (Dodonaea viscosa, Leptocophylla tameiameia) and one non-native (Morella faya) woody species (1) act as natural nodes of recruitment for native woody species and (2) can be used to enhance survivorship of outplanted native woody species. To address these questions, we quantified the presence and persistence of seedlings naturally recruiting beneath adult nurse shrubs and compared survival and growth of experimentally outplanted seedlings of seven native woody species under the nurse species compared to intact and cleared alien-grass plots. We found that the two native nurse shrubs recruit their own offspring, but do not act as establishment nodes for other species. Morella faya recruited even fewer seedlings than native shrubs. Thus, outplanting will be necessary to increase abundance and diversity of native woody species. Outplant survival was the highest under shrubs compared to away from them with few differences between nurse species. The worst habitat for native seedling survival and growth was within the unmanaged invasive grass matrix. Although the two native nurse species did not differentially affect outplant survival, D. viscosa is the most widespread and easily propagated and is thus more likely to be useful as an initial nurse species. The outplanted species showed variable responses to nurse habitats that we attribute to resource requirements resulting from their typical successional stage and nitrogen fixation capability.

  20. Effects of topoclimatic complexity on the composition of woody plant communities.

    Science.gov (United States)

    Oldfather, Meagan F; Britton, Matthew N; Papper, Prahlad D; Koontz, Michael J; Halbur, Michelle M; Dodge, Celeste; Flint, Alan L; Flint, Lorriane E; Ackerly, David D

    2016-01-01

    Topography can create substantial environmental variation at fine spatial scales. Shaped by slope, aspect, hill-position and elevation, topoclimate heterogeneity may increase ecological diversity, and act as a spatial buffer for vegetation responding to climate change. Strong links have been observed between climate heterogeneity and species diversity at broader scales, but the importance of topoclimate for woody vegetation across small spatial extents merits closer examination. We established woody vegetation monitoring plots in mixed evergreen-deciduous woodlands that spanned topoclimate gradients of a topographically heterogeneous landscape in northern California. We investigated the association between the structure of adult and regenerating size classes of woody vegetation and multidimensional topoclimate at a fine scale. We found a significant effect of topoclimate on both single-species distributions and community composition. Effects of topoclimate were evident in the regenerating size class for all dominant species (four Quercus spp., Umbellularia californica and Pseudotsuga menziesii) but only in two dominant species (Quercus agrifolia and Quercus garryana) for the adult size class. Adult abundance was correlated with water balance parameters (e.g. climatic water deficit) and recruit abundance was correlated with an interaction between the topoclimate parameters and conspecific adult abundance (likely reflecting local seed dispersal). However, in all cases, the topoclimate signal was weak. The magnitude of environmental variation across our study site may be small relative to the tolerance of long-lived woody species. Dispersal limitations, management practices and patchy disturbance regimes also may interact with topoclimate, weakening its influence on woody vegetation distributions. Our study supports the biological relevance of multidimensional topoclimate for mixed woodland communities, but highlights that this relationship might be mediated by

  1. Does the edge effect influence plant community structure in a tropical dry forest?

    Directory of Open Access Journals (Sweden)

    Diogo Gallo Oliveira

    2013-04-01

    Full Text Available Edge effects are considered a key factor in regulating the structure of plant communities in different ecosystems. However, regardless to few studies, edge influence does not seem to be decisive in semiarid regions such as the Brazilian tropical dry forest known as Caatinga but this issue remains inconclusive. The present study tests the null hypothesis that the plant community of shrubs and trees does not change in its structure due to edge effects. Twenty-four plots (20 x 20 m were set up in a fragment of Caatinga, in which 12 plots were in the forest edges and 12 plots were inside the fragment. Tree richness, abundance and species composition did not differ between edge and interior plots. The results of this study are in agreement with the pattern previously found for semiarid environments and contrasts with previous results obtained in different environments such as Rainforests, Savanna and Forest of Araucaria, which indicate abrupt differences between the border and interior of the plant communities in these ecosystems, and suggest that the community of woody plants of the Caatinga is not ecologically affected by the presence of edges.

  2. Trace element accumulation in woody plants of the Guadiamar Valley, SW Spain: A large-scale phytomanagement case study

    International Nuclear Information System (INIS)

    Dominguez, Maria T.; Maranon, Teodoro; Murillo, Jose M.; Schulin, Rainer; Robinson, Brett H.

    2008-01-01

    Phytomanagement employs vegetation and soil amendments to reduce the environmental risk posed by contaminated sites. We investigated the distribution of trace elements in soils and woody plants from a large phytomanaged site, the Guadiamar Valley (SW Spain), 7 years after a mine spill, which contaminated the area in 1998. At spill-affected sites, topsoils (0-25 cm) had elevated concentrations of As (129 mg kg -1 ), Bi (1.64 mg kg -1 ), Cd (1.44 mg kg -1 ), Cu (115 mg kg -1 ), Pb (210 mg kg -1 ), Sb (13.8 mg kg -1 ), Tl (1.17 mg kg -1 ) and Zn (457 mg kg -1 ). Trace element concentrations in the studied species were, on average, within the normal ranges for higher plants. An exception was white poplar (Populus alba), which accumulated Cd and Zn in leaves up to 3 and 410 mg kg -1 respectively. We discuss the results with regard to the phytomanagement of trace element contaminated sites. - There is a low trace element transfer from contaminated soils to the aboveground parts of afforested woody plants under a semi-arid climate

  3. Uprooting force balance for pioneer woody plants: A quantification of the relative contribution of above- and below-ground plant architecture to uprooting susceptibility

    Science.gov (United States)

    Bywater-Reyes, S.; Wilcox, A. C.; Lightbody, A.; Skorko, K.; Stella, J. C.

    2012-12-01

    Cottonwood (Populus), willow (Salix), and tamarisk (Tamarix) populate riparian areas in many dryland regions, and their recruitment depends heavily on hydrogeomorphic conditions. The survival of pioneer woody seedlings depends in part on the establishment of root systems capable of anchoring plants in subsequent floods, and this root system development in turn influences the cohesion that plants provide to bars. The factors influencing the anchoring ability and resistance to scour of woody seedlings include plant frontal area and flexibility, root structure, and water table elevation. This study aims to quantify the factors comprising the force balance to uproot woody seedlings and saplings in two field sites characterized by different hydrologic conditions. The Bill Williams River (AZ) is an impounded river with elevated water table elevations produced by dam-released base flows. The Bitterroot River (MT) is an unimpounded river with a snowmelt hydrograph and seasonal fluctuations in river and water table elevation. We simulate uprooting from flooding events by saturating substrates and applying force near the base of the plant in a lateral, downstream direction until uprooting occurs, for a range of plant sizes but with a focus on small (plants, with cottonwood and tamarisk seedlings showing greater variability than willow. In contrast, root length and stem diameter are only weakly correlated with pull-out force. By combining pull test results with measurements of geomorphic and groundwater conditions, this study provides insights into the relative contribution of a plant's above-ground and below-ground architecture to uprooting potential and into the feedbacks between vegetation and morphodynamics on river bars.

  4. The time lag between introduction and escape from cultivation of alien woody plant species decreases with polyploidization

    Directory of Open Access Journals (Sweden)

    M. Brändle

    2012-04-01

    Full Text Available The time between introduction of an alien species and escape from cultivation shows considerable variation among species. One hypothesis to explain this variation of the time lag invokes the evolution of genotypes adapted to the conditions of the new environment. Here, we analyse the variation in time lags among 53 alien woody plant species in Germany. Accounting for the effects of time since introduction, growth form (trees versus shrubs, biogeography and taxonomic isolation (presence or absence of a native congener in the adventive area we found that the time lag decreases with increasing polyploidization. By contrast, the haploid chromosome number was not significantly related to the time lag. These results provide evidence for the hypothesis that recent genome duplication events are important for a fast escape from cultivation of an alien woody plant species. We suggest that a large number of duplicated chromosomes increase the partitioning of the genome and hence the average rate of recombination between loci facilitating the formation of adaptive genotypes.

  5. Effect of Single Selection Method on Woody and Herbaceous Plant Biodiversity in Khalil-Mahale Forest, Behshahr

    Directory of Open Access Journals (Sweden)

    Sh. Kazemi

    2015-06-01

    Full Text Available This study was undertaken to investigate the role of forest management in tree diversity, regeneration and vegetation in control and managed parcels of series No. 1 of forestry plan in Khalil-Mahale, Behshahr. Thirty samples with an area of 1000 m2 were systematically and randomly taken with a 100 × 75 m grid in both parcels. In each plot, tree number and species type were recorded. In order to study the vegetation, five micro-plots (1 m2, one in the center and four others in four main directions (half radius from the center of the plot were taken in each plot. The type and percentage of herbaceous species were recorded in each microplot. To count the regeneration in the center of the main plot, circular sample plots with an area of 100 m2 were used. To study and compare the biodiversity in the two plots and to calculate the richness and evenness, the Simpson and Shannon-Wiener diversity indices, Margalef and Menhinic indices and the Pilo index were used, respectively, using PAST software. The results showed that the number of plant species was more in managed plots. The biodiversity of woody and herbaceous plants richness indices and regeneration of tree species were higher in managed plots. In fact, the results showed that forest management using single selection method had different effects on woody species regeneration and diversity of herbaceous and tree species.

  6. Effect of feeding some evergreen tropical browse plant leaves on ...

    African Journals Online (AJOL)

    A feeding trial was conducted with thirty (30) weaner rabbits to investigate the nutritive potentials of some evergreen tropical browse plant leaves (Ficcus thoningii, Vitex doniana, Daniela oliveri, Sarcocephalus latifolia). Mixed breed rabbits were used and randomly assigned to five (5) treatments (T1 - T5). The rabbits in ...

  7. ISOLATION OF MESOPHYLL PROTOPLASTS FROM MEDITERRANEAN WOODY PLANTS FOR THE STUDY OF DNA INTEGRITY UNDER ABIOTIC STRESS

    Directory of Open Access Journals (Sweden)

    Elena Kuzminsky

    2016-08-01

    Full Text Available Abiotic stresses have considerable negative impact on Mediterranean plant ecosystems and better comprehension of the genetic control of response and adaptation of trees to global changes is urgently needed. The Single Cell Gel Electrophoresis assay could be considered a good estimator of DNA damage in an individual eukaryotic cell. This method has been mainly employed in animal tissues, because the plant cell wall represents an obstacle for the extraction of nuclei; moreover, in Mediterranean woody species, especially in the sclerophyll plants, this procedure can be quite difficult because of the presence of sclerenchyma and hardened cells. On the other hand, these plants represent an interesting material to be studied because of the ability of these plants to tolerate abiotic stress. For instance, holm oak (Quercus ilex L. has been selected as the model plant to identify critical levels of O3 for Southern European forests. Consequently, a quantitative method for the evaluation of cell injury of leaf tissues of this species is required. Optimal conditions for high-yield nuclei isolation were obtained by using protoplast technology and a detailed description of the method is provided and discussed. White poplar (Populus alba L. was used as an internal control for protoplast isolation. Such a method has not been previously reported in newly fully developed leaves of holm oak. This method combined with Single Cell Gel Electrophoresis assay represents a new tool for testing the DNA integrity of leaf tissues in higher plants under stress conditions.

  8. Assessing the Potential of Low-Cost 3D Cameras for the Rapid Measurement of Plant Woody Structure

    Directory of Open Access Journals (Sweden)

    Charles Nock

    2013-11-01

    Full Text Available Detailed 3D plant architectural data have numerous applications in plant science, but many existing approaches for 3D data collection are time-consuming and/or require costly equipment. Recently, there has been rapid growth in the availability of low-cost, 3D cameras and related open source software applications. 3D cameras may provide measurements of key components of plant architecture such as stem diameters and lengths, however, few tests of 3D cameras for the measurement of plant architecture have been conducted. Here, we measured Salix branch segments ranging from 2–13 mm in diameter with an Asus Xtion camera to quantify the limits and accuracy of branch diameter measurement with a 3D camera. By scanning at a variety of distances we also quantified the effect of scanning distance. In addition, we also test the sensitivity of the program KinFu for continuous 3D object scanning and modeling as well as other similar software to accurately record stem diameters and capture plant form (<3 m in height. Given its ability to accurately capture the diameter of branches >6 mm, Asus Xtion may provide a novel method for the collection of 3D data on the branching architecture of woody plants. Improvements in camera measurement accuracy and available software are likely to further improve the utility of 3D cameras for plant sciences in the future.

  9. Changes in bird community composition in response to growth changes in short-rotation woody crop planting

    International Nuclear Information System (INIS)

    Tolbert, V.R.; Hanowski, J.; Schiller, A.; Hoffman, W.; Christian, D.; Lindberg, J.

    1997-01-01

    Hybrid poplar established as intensively managed short-rotation woody crops (SRWC) on former agricultural lands can provide habitat for wildlife. Studies of bird use of SRWC for nesting and during fall migration have shown that the numbers and kinds of breeding birds using mature plantings of hybrid poplar are similar to natural forested lands. In Minnesota, the number of species of breeding birds using habitat provided by clonal-trial plantings and young larger-scale plantings (12-64 ha) of hybrid poplar were initially most similar to those using grasslands and row-crops. As the plantings approached canopy closure, successional species became predominant. In the Pacific Northwest, breeding bird composition and density were very similar for mature plantings and forested areas; however, fall migrants were found primarily in forested areas. In the Southeast, preliminary comparisons of breeding bird use of plantings of sweetgum and sycamore with naturally regenerating forests of different ages and sizes and vegetation structure are showing no size effect on use. As with hybrid poplar, species use of the more mature plantings of sweetgum and sycamore was most similar to that of natural forests. (author)

  10. Heavy metal concentrations in redeveloping soil of mine spoil under plantations of certain native woody species in dry tropical environment, India

    Energy Technology Data Exchange (ETDEWEB)

    Singh, A.N.; Zeng, D.H.; Chen, F.S. [Chinese Academy of Science, Shenyang (China). Inst. of Applied Ecology

    2005-07-01

    Total concentration of heavy metals (Cd, Cr, Cu, Fe, Pb, Ni, Mn and Zn) was estimated in the redeveloping soil of mine spoil under 5-yr old plantations of four woody species namely: Albizia lebbeck, Albizia procera, Tectona grandis and Dendrocalamus strictus. The data recorded in the present study were compared with other unplanted coal mine spoil colliery, which was around to the study site and adjoining area of dry tropical forest. Among all the heavy metals, the maximum concentration was found for Fe and minimum for Cd. However, among all four species, total concentrations of these heavy metals were recorded maximally in the plantation plots of T. grandis except for Fe, while minimally in A. lebbeck except for Zn, whereas, the maximum concentration of Fe and Zn was in the plantation plots of D. strictus and A. procera. Statistical analysis revealed significant differences due to species for all the heavy metals except Cu. Among four species, A. lebbeck, A. procera and D. strictus showed more efficient for reducing heavy metal concentrations whereas T. grandis was not more effective to reduce heavy metal concentrations in redeveloping soil of mine spoil.

  11. Heavy metal concentrations in redeveloping soil of mine spoil under plantations of certain native woody species in dry tropical environment, India.

    Science.gov (United States)

    Singh, Anand N; Zeng, De-hui; Chen, Fu-sheng

    2005-01-01

    Total concentration of heavy metals (Cd, Cr, Cu, Fe, Pb, Ni, Mn and Zn) was estimated in the redeveloping soil of mine spoil under 5-yr old plantations of four woody species namely: Albizia lebbeck, Albizia procera, Tectona grandis and Dendrocalamus strictus. The data recorded in the present study were compared with other unplanted coal mine spoil colliery, which was around to the study site and adjoining area of dry tropical forest. Among all the heavy metals, the maximum concentration was found for Fe and minimum for Cd. However, among all four species, total concentrations of these heavy metals were recorded maximally in the plantation plots of T. grandis except for Fe, while minimally in A. lebbeck except for Zn, whereas, the maximum concentration of Fe and Zn was in the plantation plots of D. strictus and A. procera. Statistical analysis revealed significant differences due to species for all the heavy metals except Cu. Among four species, A. lebbeck, A. procera and D. strictus showed more efficient for reducing heavy metal concentrations whereas T. grandis was not more effective to reduce heavy metal concentrations in redeveloping soil of mine spoil.

  12. Planting woody crops on dredged contaminated sediment provides both positive and negative effects in terms of remediation

    International Nuclear Information System (INIS)

    Hartley, William; Riby, Philip; Dickinson, Nicholas M.; Shutes, Brian; Sparke, Shaun; Scholz, Miklas

    2011-01-01

    There is currently a requirement for studies focusing on the long-term sustainability of phytoremediation technologies. Trace element uptake by Salix, Populus and Alnus species planted in dredged contaminated canal sediment and concentrations in sediment and pore waters were investigated, eight years after a phytoremediation trial was initiated in NW England. Soil biological activity was also measured using invertebrate and microbial assays to determine soil quality improvements. Zinc was the dominant trace metal in foliage and woody stems, and the most mobile trace element in sediment pore water (∼14 mg l -1 ). Biological activity had improved; earthworm numbers had increased from 5 to 24, and the QBS index (an index of microarthropod groups in soil) had increased from 70 to 88. It is concluded that biological conditions had improved and natural processes appear to be enhancing soil quality, but there remains a potential risk of trace element transfer to the wider environment. - Highlights: → Trees provide positive and negative effects for remediation of dredged sediment. → Biological conditions had improved and natural processes enhance soil quality. → Zinc was the dominant trace metal in foliage and sediment pore waters. → Metal contaminants remain a problem in relation to their wider environmental fate. → A sustainable environment appears to be forming as a result of natural attenuation. - Soil biological quality improves in a woody crop stand eight years after a phytoremediation trial.

  13. Planting woody crops on dredged contaminated sediment provides both positive and negative effects in terms of remediation

    Energy Technology Data Exchange (ETDEWEB)

    Hartley, William, E-mail: w.hartley@salford.ac.uk [School of Computing, Science and Engineering, University of Salford, Cockcroft Building, Salford M5 4WT (United Kingdom); Riby, Philip [School of Pharmacy and Biomolecular Sciences, Liverpool John Moores University, Byrom Street, Liverpool L3 3AF (United Kingdom); Dickinson, Nicholas M. [Department of Ecology, Lincoln University, Lincoln 7647, Canterbury (New Zealand); Shutes, Brian [Urban Pollution Research Centre, Department of Natural Sciences, Middlesex University, Hendon, London NW4 4BT (United Kingdom); Sparke, Shaun [School of Pharmacy and Biomolecular Sciences, Liverpool John Moores University, Byrom Street, Liverpool L3 3AF (United Kingdom); Scholz, Miklas [School of Computing, Science and Engineering, University of Salford, Cockcroft Building, Salford M5 4WT (United Kingdom)

    2011-12-15

    There is currently a requirement for studies focusing on the long-term sustainability of phytoremediation technologies. Trace element uptake by Salix, Populus and Alnus species planted in dredged contaminated canal sediment and concentrations in sediment and pore waters were investigated, eight years after a phytoremediation trial was initiated in NW England. Soil biological activity was also measured using invertebrate and microbial assays to determine soil quality improvements. Zinc was the dominant trace metal in foliage and woody stems, and the most mobile trace element in sediment pore water ({approx}14 mg l{sup -1}). Biological activity had improved; earthworm numbers had increased from 5 to 24, and the QBS index (an index of microarthropod groups in soil) had increased from 70 to 88. It is concluded that biological conditions had improved and natural processes appear to be enhancing soil quality, but there remains a potential risk of trace element transfer to the wider environment. - Highlights: > Trees provide positive and negative effects for remediation of dredged sediment. > Biological conditions had improved and natural processes enhance soil quality. > Zinc was the dominant trace metal in foliage and sediment pore waters. > Metal contaminants remain a problem in relation to their wider environmental fate. > A sustainable environment appears to be forming as a result of natural attenuation. - Soil biological quality improves in a woody crop stand eight years after a phytoremediation trial.

  14. Does the growth response of woody plants to elevated CO2 increase with temperature? A model-oriented meta-analysis.

    Science.gov (United States)

    Baig, Sofia; Medlyn, Belinda E; Mercado, Lina M; Zaehle, Sönke

    2015-12-01

    The temperature dependence of the reaction kinetics of the Rubisco enzyme implies that, at the level of a chloroplast, the response of photosynthesis to rising atmospheric CO2 concentration (Ca ) will increase with increasing air temperature. Vegetation models incorporating this interaction predict that the response of net primary productivity (NPP) to elevated CO2 (eCa ) will increase with rising temperature and will be substantially larger in warm tropical forests than in cold boreal forests. We tested these model predictions against evidence from eCa experiments by carrying out two meta-analyses. Firstly, we tested for an interaction effect on growth responses in factorial eCa  × temperature experiments. This analysis showed a positive, but nonsignificant interaction effect (95% CI for above-ground biomass response = -0.8, 18.0%) between eCa and temperature. Secondly, we tested field-based eCa experiments on woody plants across the globe for a relationship between the eCa effect on plant biomass and mean annual temperature (MAT). This second analysis showed a positive but nonsignificant correlation between the eCa response and MAT. The magnitude of the interactions between CO2 and temperature found in both meta-analyses were consistent with model predictions, even though both analyses gave nonsignificant results. Thus, we conclude that it is not possible to distinguish between the competing hypotheses of no interaction vs. an interaction based on Rubisco kinetics from the available experimental database. Experiments in a wider range of temperature zones are required. Until such experimental data are available, model predictions should aim to incorporate uncertainty about this interaction. © 2015 John Wiley & Sons Ltd.

  15. Tropical plant pathology: at home and abroad.

    Science.gov (United States)

    Thurston, H D

    2001-01-01

    I first describe my introduction to plant pathology and early experiences with employment, the environment, diseases, pests, and various plant pathologists. Then I recount a decade of stimulating studies at the University of Minnesota and the route I followed to a career in international agriculture with the Rockefeller Foundation in Colombia and later at Cornell University. My appreciation for and knowledge of traditional farmers and sustainable agriculture occurred as a slow awakening. Comments are made regarding problems, principles, and satisfactions associated with the improvement of efforts to aid food production in developing countries. My curious love affair with root and tuber crops, especially cassava, is explained and readily defended. My favorite pathogens, Phytophthora infestans and Ralstonia solanacearum, among others, are considered. The pleasures and satisfactions of teaching, writing, and sabbatical leaves are related. Finally, thoughts on the balance between basic and applied research in plant pathology are offered with significant nervousness about the future of our discipline.

  16. Quantitative market survey of non-woody plants sold at Kariakoo Market in Dar es Salaam, Tanzania.

    Science.gov (United States)

    Posthouwer, Chantal; Veldman, Sarina; Abihudi, Siri; Otieno, Joseph N; van Andel, Tinde R; de Boer, Hugo J

    2018-04-30

    In Tanzania, traditional medicine plays a significant role in health care and local economies based on the harvesting, trade and sale of medicinal plant products. The majority of this plant material is said to originate from wild sources, and both traditional healers and vendors are concerned about the increasing scarcity of certain species. A market survey of non-powdered, non-woody medicinal plants was conducted at Kariakoo Market in Dar es Salaam, the major hub for medicinal plant trade in Tanzania, to assess sustainability of traded herbal medicine. For this study, fresh and dried herbs, seeds and fruits were collected and interviews were conducted to obtain information on vernacular names, preparation methods, monthly sales, uses and prices. Bundles of herbal medicine offered for sale were weighed and counted to calculate the value and volumes of daily stock at the market. A total of 71 medicinal plant products belonging to 62 to 67 different species from at least 41 different plant families were identified. We identified 45 plant products to species level, 20 products to genus level and four to family level. Plant species most encountered at the market were Suregada zanzibariensis, Myrothamnus flabellifolia and Sclerocarya birrea. The major use categories reported by the vendors were ritual purposes, digestive disorders and women's health. Annual sales are estimated to be in excess of 30 t and close to 200,000 USD, and trade in herbal medicine at Kariakoo Market provides subsistence income to many local vendors. A large diversity of wild-harvested plant species is traded as medicinal products in Tanzania, including species listed on CITES Appendices. Identifying and monitoring temporal changes in availability per season and from year to year will reveal which species are most affected by this trade, and help relevant authorities in Tanzania to find alternative sources of income for dependent stakeholders and initiate targeted efforts to protect threatened

  17. Development of a new steady state zero-dimensional simulation model for woody biomass gasification in a full scale plant

    International Nuclear Information System (INIS)

    Formica, Marco; Frigo, Stefano; Gabbrielli, Roberto

    2016-01-01

    Highlights: • A simulation model with Aspen Plus is created for a full scale biomass gasification plant. • Test results, equipment data and control logics are considered in the simulation model. • The simulation results are in agreement with the experimental data. • The gasifying air temperature affects largely the energy performance of the gasification plant. • Increasing the equivalent ratio implies a strong reduction of the gasification efficiency. - Abstract: A new steady state zero-dimensional simulation model for a full-scale woody biomass gasification plant with fixed-bed downdraft gasifier has been developed using Aspen Plus®. The model includes the technical characteristics of all the components (gasifier, cyclone, exchangers, piping, etc.) of the plant and works in accordance with its actual main control logics. Simulation results accord with those obtained during an extensive experimental activity. After the model validation, the influence of operating parameters such as the equivalent ratio, the biomass moisture content and the gasifying air temperature on syngas composition have been analyzed in order to assess the operative behavior and the energy performance of the experimental plant. By recovering the sensible heat of the syngas at the outlet of the gasifier, it is possible to obtain higher values of the gasifying air temperature and an improvement of the overall gasification performances.

  18. On the global relationships between photosynthetic water-use efficiency, leaf mass per unit area and atmospheric demand in woody and herbaceous plants

    Science.gov (United States)

    Letts, M. G.; Fox, T. A.; Gulias, J.; Galmes, J.; Hikosaka, K.; Wright, I.; Flexas, J.; Awada, T.; Rodriguez-Calcerrada, J.; Tobita, H.

    2013-12-01

    A global dataset was compiled including woody and herbaceous C3 species from forest, Mediterranean and grassland-shrubland ecosystems, to elucidate the dependency of photosynthetic water-use efficiency on vapour pressure deficit (D) and leaf traits. Mean leaf mass per unit area (LMA) was lower and mass-based leaf nitrogen content (Nmass) was higher in herbaceous species. Higher mean stomatal conductance (gs), transpiration rate (E) and net CO2 assimilation rate under light saturating conditions (Amax) were observed in herbs, but photosynthetic and intrinsic water-use efficiencies (WUE = Amax/E and WUEi = Amax/gs) were lower than in woody plants. Woody species maintained stricter stomatal regulation of water loss at low D, resulting in a steeper positive and linear relationship between log D and log E. Herbaceous species possessed very high gs at low D, resulting in higher ratio of substomatal to atmospheric CO2 concentrations (ci/ca) and E, but lower WUE and WUEi than woody plants, despite higher Amax. The lower WUE and higher rates of gas exchange were most pronounced in herbs with low LMA and high Nmass. Photosynthetic water use also differed between species from grassland-shrubland and Mediterranean or forest environments. Water-use efficiency showed no relationship with either D or LMA in grassland-shrubland species, but showed a negative relationship with D in forest and chaparral. The distinct photosynthetic water-use of woody and herbaceous plants is consistent with the opportunistic growth strategy of herbs and the more conservative growth strategy of woody species. Further research is recommended to examine the implications of these functional group and ecosystem differences in the contexts of climate and atmospheric change.

  19. Effects of growth form and functional traits on response of woody plants to clearing and fragmentation of subtropical rainforest.

    Science.gov (United States)

    Kooyman, R M; Zanne, A E; Gallagher, R V; Cornwell, W; Rossetto, M; O'Connor, P; Parkes, E A; Catterall, C F; Laffan, S W; Lusk, C H

    2013-12-01

    The conservation implications of large-scale rainforest clearing and fragmentation on the persistence of functional and taxonomic diversity remain poorly understood. If traits represent adaptive strategies of plant species to particular circumstances, the expectation is that the effect of forest clearing and fragmentation will be affected by species functional traits, particularly those related to dispersal. We used species occurrence data for woody plants in 46 rainforest patches across 75,000 ha largely cleared of forest by the early 1900s to determine the combined effects of area reduction, fragmentation, and patch size on the taxonomic structure and functional diversity of subtropical rainforest. We compiled species trait values for leaf area, seed dry mass, wood density, and maximum height and calculated species niche breadths. Taxonomic structure, trait values (means, ranges), and the functional diversity of assemblages of climbing and free-standing plants in remnant patches were quantified. Larger rainforest patches had higher species richness. Species in smaller patches were taxonomically less related than species in larger patches. Free-standing plants had a high percentage of frugivore dispersed seeds; climbers had a high proportion of small wind-dispersed seeds. Connections between the patchy spatial distribution of free-standing species, larger seed sizes, and dispersal syndrome were weak. Assemblages of free-standing plants in patches showed more taxonomic and spatial structuring than climbing plants. Smaller isolated patches retained relatively high functional diversity and similar taxonomic structure to larger tracts of forest despite lower species richness. The response of woody plants to clearing and fragmentation of subtropical rainforest differed between climbers and slow-growing mature-phase forest trees but not between climbers and pioneer trees. Quantifying taxonomic structure and functional diversity provides an improved basis for

  20. Overexpression of a peach CBF gene in apple: a model for understanding the integration of growth, dormancy, and cold hardiness in woody plants

    Science.gov (United States)

    The timing of cold acclimation and de-acclimation, dormancy, and bud break play an integral role in the life cycle of woody plants. The molecular events that regulate these parameters have been the subject of much study, however, in most studies these events have been investigated independently of ...

  1. Integrating Measures of Soil Respiration Across Spatial and Temporal Scales Along a Woody Plant Encroachment Gradient Using Traditional and Innovative Techniques 2027

    Science.gov (United States)

    Understanding the response of arid and semi-arid systems to changes in woody plant cover is an area of active research. Shifts in vegetation structure or function in these water-limited systems can have important and non-linear affects on ecosystem function and biogeochemical cycling. Most studies, ...

  2. A Regional Study of Loblolly Pine (Pinus taeda) Plantation Development During the First 15 Years After Early Complete Woody and/or Herbaceous Plant Control

    Science.gov (United States)

    James H. Miller; Bruce R. Zutter; Shepard M. Zedaker; M. Boyd Edwards; Ray A. Newbold

    2002-01-01

    Conifer plantations in North America and elsewhere in the world are increasingly cultured using early control of herbaceous and woody plants. Development of sustainable cultural practices are hindered by the absence of long-term data on productivity gains relative to competition levels, crop- competition dynamics, and ecological changes. There are lmany reports of...

  3. Variation in woody plant mortality and dieback from severe drought among soils, plant groups, and species within a northern Arizona ecotone.

    Science.gov (United States)

    Koepke, Dan F; Kolb, Thomas E; Adams, Henry D

    2010-08-01

    Vegetation change from drought-induced mortality can alter ecosystem community structure, biodiversity, and services. Although drought-induced mortality of woody plants has increased globally with recent warming, influences of soil type, tree and shrub groups, and species are poorly understood. Following the severe 2002 drought in northern Arizona, we surveyed woody plant mortality and canopy dieback of live trees and shrubs at the forest-woodland ecotone on soils derived from three soil parent materials (cinder, flow basalt, sedimentary) that differed in texture and rockiness. Our first of three major findings was that soil parent material had little effect on mortality of both trees and shrubs, yet canopy dieback of trees was influenced by parent material; dieback was highest on the cinder for pinyon pine (Pinus edulis) and one-seed juniper (Juniperus monosperma). Ponderosa pine (Pinus ponderosa) dieback was not sensitive to parent material. Second, shrubs had similar mortality, but greater canopy dieback, than trees. Third, pinyon and ponderosa pines had greater mortality than juniper, yet juniper had greater dieback, reflecting different hydraulic characteristics among these tree species. Our results show that impacts of severe drought on woody plants differed among tree species and tree and shrub groups, and such impacts were widespread over different soils in the southwestern U.S. Increasing frequency of severe drought with climate warming will likely cause similar mortality to trees and shrubs over major soil types at the forest-woodland ecotone in this region, but due to greater mortality of other tree species, tree cover will shift from a mixture of species to dominance by junipers and shrubs. Surviving junipers and shrubs will also likely have diminished leaf area due to canopy dieback.

  4. 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

  5. Tropical dry forest status and relative importance of woody flora, islands of Old Providence and Santa Catalina, Colombia, Southwestern Caribbean

    International Nuclear Information System (INIS)

    Linares, Jorge Ruiz; Fandino Orozco, Maria Claudia

    2009-01-01

    The purpose of this paper is to present evidence on the condition of the Dry Tropical Forest (DtF) in Old Providence. A chronological study was carried out in order to assess the land cover change in DtF between 1944 and 2005. Additionally, we established 109 plots 2 x 50 m, following the protocol by Gentry (1982); and species abundance models were fitted to the data. It is concluded that up to 2000 the forest recovered, yet, in 2005 it retreated to 1990 levels. The lognormal distribution suggests that the forest is indeed in good condition. Anacardiaceae is the family with the highest Importance Value Index (IVI) while Acacia collinsii is the species with the highest IVI.

  6. Optimal Level of Woody Biomass Co-Firing with Coal Power Plant Considering Advanced Feedstock Logistics System

    Directory of Open Access Journals (Sweden)

    Sangpil Ko

    2018-05-01

    Full Text Available Co-firing from woody biomass feedstock is one of the alternatives toward increased use of renewable feedstock in existing coal power plants. However, the economic level of co-firing at a particular power plant depends on several site-specific factors. Torrefaction has been identified recently as a promising biomass pretreatment option to lead to reduction of the feedstock delivered cost, and thus facilitate an increase in the co-firing ratio. In this study, a mixed integer linear program (MILP is developed to integrate supply chain of co-firing and torrefaction process and find the optimal level of biomass co-firing in terms of minimized transportation and logistics costs, with or without tax credits. A case study of 26 existing coal power plants in three Great Lakes States of the US is used to test the model. The results reveal that torrefaction process can lead to higher levels of co-firing, but without the tax credit, the effect is limited to the low capacity of power plants. The sensitivity analysis shows that co-firing ratio has higher sensitivity to variation in capital and operation costs of torrefaction than to the variation in the transportation and feedstock purchase costs.

  7. Where are the tropical plants? A call for better inclusion of tropical plants in studies investigating and predicting the effects of climate change

    Directory of Open Access Journals (Sweden)

    Kenneth J Feeley

    2016-01-01

    Full Text Available Tropical plant species are systematically underrepresented in large-scale analyses or synthesis looking at the potential effects of global climate change.  The reason being that we simply don’t know enough about the distributions and ecologies of most tropical plant species to predict their fate under climate change. This gaping hole in our knowledge is extremely worrisome given the high diversity of tropical plants, the crucial roles that they play in supporting global diversity and ecosystem function, and the elevated threats that climate change may pose to tropical species in general.  

  8. Peatland Woody Plant Growth Responses to Warming and Elevated CO2 in a Southern-boreal Raised Bog Ecosystem

    Science.gov (United States)

    Phillips, J. R.; Hanson, P. J.; Warren, J.; Ward, E. J.; Brice, D. J.; Graham, J.

    2017-12-01

    Spruce and Peatland Responses Under Changing Environments (SPRUCE) is an in situ warming by elevated CO2 manipulation located in a high-carbon, spruce peatland in northern Minnesota. Warming treatments combined a 12-m diameter open topped chamber with internally recirculating warm air and soil deep heating to simulate a broad range of future warming treatments. Deep below ground soil warming rates are 0, +2.25, +4.5, +6.75, and +9 °C. Deep belowground warming was initiated in June 2014 followed by air warming in August 2015. In June 2016, elevated CO2 atmospheres (eCO2 at + 500 ppm) were added to half of the warming treatments in a regression design. Our objective was to track long-term vegetation responses to warming and eCO2. Annual tree growth is based on winter measurement of circumference of all Picea mariana and Larix laricina trees within each 113 m2 plot, automated dendrometers, terrestrial LIDAR scanning of tree heights and canopy volumes, and destructive allometry. Annual shrub growth is measured in late summer by destructive clipping in two 0.25 m2 sub-plots and separation of the current year tissues. During the first year of warming, tree basal area growth was reduced for Picea, but not Larix trees. Growth responses for the woody shrub vegetation remains highly variable with a trend towards increasing growth with warming. Elevated CO2 enhancements of growth are not yet evident in the data. Second-year results will also be reported. Long-term hypotheses for increased woody plant growth under warming include potential enhancements driven by increased nutrient availability from warming induced decomposition of surface peats.

  9. Chronic human disturbance affects plant trait distribution in a seasonally dry tropical forest

    Science.gov (United States)

    Sfair, Julia C.; de Bello, Francesco; de França, Thaysa Q.; Baldauf, Cristina; Tabarelli, Marcelo

    2018-02-01

    The effects of human disturbance on biodiversity can be mediated by environmental conditions, such as water availability, climate and nutrients. In general, disturbed, dry or nutrient-depleted soils areas tend to have lower taxonomic diversity. However, little is known about how these environmental conditions affect functional composition and intraspecific variability in tropical dry forests. We studied a seasonally dry tropical forest (SDTF) under chronic anthropogenic disturbance (CAD) along rainfall and soil nutrient gradients to understand how these factors influence the taxonomic and functional composition. Specifically we evaluated two aspects of CAD, wood extraction and livestock pressure (goat and cattle grazing), along soil fertility and rainfall gradients on shrub and tree traits, considering species turnover and intraspecific variability. In addition, we also tested how the traits of eight populations of the most frequent species are affected by wood extraction, livestock pressure, rainfall and soil fertility. In general, although CAD and environmental gradients affected each trait of the most widespread species differently, the most abundant species also had a greater variation of traits. Considering species turnover, wood extraction is associated with species with a smaller leaf area and lower investment in leaf mass, probably due to the indirect effects of this disturbance type on the vegetation, i.e. the removal of branches and woody debris clears the vegetation, favouring species that minimize water loss. Livestock pressure, on the other hand, affected intraspecific variation: the herbivory caused by goats and cattle promoted individuals which invest more in wood density and leaf mass. In this case, the change of functional composition observed is a direct effect of the disturbance, such as the decrease of palatable plant abundance by goat and cattle herbivory. In synthesis, CAD, rainfall and soil fertility can affect trait distribution at community

  10. Eleventh-year results of fertilization, herbaceous, and woody plant control in a loblolly pine plantation

    Science.gov (United States)

    James D. Haywood; Allan E. Tiarks

    1990-01-01

    Through 11 years, fertilization at planting significantly increased the stemwood volume (outside bark) per loblolly pine (Pinus taeda L.) on an intensively prepared moderately well-drained fine sandy loam site in northern Louisiana. Four years of herbaceous plant control significantly increased pine survival, and because herbaceous plant control...

  11. Towards restoration of Hawaiian tropical dry forests: the Kaupulehu outplanting programme

    Science.gov (United States)

    Susan Cordell; Moana McClellan; Yvonne Yarber Carter; Lisa J. Hadway

    2008-01-01

    Hawaiian tropical dry forests contain diverse assemblages of woody canopy species, including many endemic and endangered species that warrant conservation attention before completely disappearing. Today, tropical dry forests in Hawaii are not viable ecosystems. Poor land use practices, fragmentation, non-native plant invasions, and inadequate native vegetation...

  12. Seasonal trends in reduced leaf gas exchange and ozone-induced foliar injury in three ozone sensitive woody plant species

    Energy Technology Data Exchange (ETDEWEB)

    Novak, K. [Swiss Federal Institute for Forest, Snow and Landscape Research WSL, Zuercherstrasse 111, 8903 Birmensdorf (Switzerland)]. E-mail: kristopher.novak@wsl.ch; Schaub, M. [Swiss Federal Institute for Forest, Snow and Landscape Research WSL, Zuercherstrasse 111, 8903 Birmensdorf (Switzerland); Fuhrer, J. [Swiss Federal Research Station for Agroecology and Agriculture FAL, 8046 Zurich (Switzerland); Skelly, J.M. [Department of Plant Pathology, The Pennsylvania State University, University Park, PA 16802 (United States); Hug, C. [Swiss Federal Institute for Forest, Snow and Landscape Research WSL, Zuercherstrasse 111, 8903 Birmensdorf (Switzerland); Landolt, W. [Swiss Federal Institute for Forest, Snow and Landscape Research WSL, Zuercherstrasse 111, 8903 Birmensdorf (Switzerland); Bleuler, P. [Swiss Federal Institute for Forest, Snow and Landscape Research WSL, Zuercherstrasse 111, 8903 Birmensdorf (Switzerland); Kraeuchi, N. [Swiss Federal Institute for Forest, Snow and Landscape Research WSL, Zuercherstrasse 111, 8903 Birmensdorf (Switzerland)

    2005-07-15

    Seasonal trends in leaf gas exchange and ozone-induced visible foliar injury were investigated for three ozone sensitive woody plant species. Seedlings of Populus nigra L., Viburnum lantana L., and Fraxinus excelsior L. were grown in charcoal-filtered chambers, non-filtered chambers and open plots. Injury assessments and leaf gas exchange measurements were conducted from June to October during 2002. All species developed typical ozone-induced foliar injury. For plants exposed to non-filtered air as compared to the charcoal-filtered air, mean net photosynthesis was reduced by 25%, 21%, and 18% and mean stomatal conductance was reduced by 25%, 16%, and 8% for P. nigra, V. lantana, and F. excelsior, respectively. The timing and severity of the reductions in leaf gas exchange were species specific and corresponded to the onset of visible foliar injury. - Reductions in leaf gas exchange corresponded to the onset of ozone-induced visible foliar injury for seedlings exposed to ambient ozone exposures.

  13. Seasonal trends in reduced leaf gas exchange and ozone-induced foliar injury in three ozone sensitive woody plant species

    International Nuclear Information System (INIS)

    Novak, K.; Schaub, M.; Fuhrer, J.; Skelly, J.M.; Hug, C.; Landolt, W.; Bleuler, P.; Kraeuchi, N.

    2005-01-01

    Seasonal trends in leaf gas exchange and ozone-induced visible foliar injury were investigated for three ozone sensitive woody plant species. Seedlings of Populus nigra L., Viburnum lantana L., and Fraxinus excelsior L. were grown in charcoal-filtered chambers, non-filtered chambers and open plots. Injury assessments and leaf gas exchange measurements were conducted from June to October during 2002. All species developed typical ozone-induced foliar injury. For plants exposed to non-filtered air as compared to the charcoal-filtered air, mean net photosynthesis was reduced by 25%, 21%, and 18% and mean stomatal conductance was reduced by 25%, 16%, and 8% for P. nigra, V. lantana, and F. excelsior, respectively. The timing and severity of the reductions in leaf gas exchange were species specific and corresponded to the onset of visible foliar injury. - Reductions in leaf gas exchange corresponded to the onset of ozone-induced visible foliar injury for seedlings exposed to ambient ozone exposures

  14. Changes in Photosystem Ⅱ Activity and Leaf Reflectance Features of Several Subtropical Woody Plants Under Simulated SO2 Treatment

    Institute of Scientific and Technical Information of China (English)

    Nan Liu; Chang-Lian Peng; Zhi-Fang Lin; Gui-Zhu Lin; Ling-Ling Zhang; Xiao-Ping Pan

    2006-01-01

    The effects of simulated SO2 treatment on the photosynthetic apparatus were investigated in five subtropical forest plants, namely Pinus massoniana Lamb., Schima superba Gardn. et Champ., Castanopsis fissa (Champ. ex Benth.) Rehd. et Wils., Acmena acuminatissima (BI.) Merr et Perry, and Cryptocarya concinna Hance. After leaf sections had been immersed in 0, 20, 50, and 100 mmol/L NaHSO3 for 20 h, total chlorophyll (Chl) content, Chl a/b, maximal photochemical efficiency, and the photochemical quantum yields of photosystem Ⅱ of all five woody plants were reduced to different degrees, whereas lutein content (Chl base) was increased. Two protective mechanisms, namely the xanthophyll cycle (de-epoxidation) and an anti-oxidant system (1,1-diphenyl-2-picrylhydrazyl radical-scavenging capacity), showed differences in the degree of modulation under simulated SO2 treatment. Compared with control (distilled water treatment), the revised normalized difference vegetation index, a leaf reflectance index, was lowered with increasing concentrations of NaHSO3. Cryptocarya concinna, a dominant species in the late succession stage of subtropical forests in South China, exhibited less sensitivity to NaHSO3. Conversely, Pinus massoniana, the pioneer heliophyte species, was most susceptible to NaHSO3 treatment. It is suggested that SO2 pollution may accelerate the succession of subtropical forest.

  15. Do tropical wetland plants possess a convective gas flow mechanism?

    DEFF Research Database (Denmark)

    Jensen, Dennis Konnerup; Sorrell, Brian Keith; Brix, Hans

    2011-01-01

    Internal pressurization and convective gas flow, which can aerate wetland plants more efficiently than diffusion, are common in temperate species. Here, we present the first survey of convective flow in a range of tropical plants. The occurrence of pressurization and convective flow was determined...... in 20 common wetland plants from the Mekong Delta in Vietnam. The diel variation in pressurization in culms and the convective flow and gas composition from stubbles were examined for Eleocharis dulcis, Phragmites vallatoria and Hymenachne acutigluma, and related to light, humidity and air temperature....... Nine of the 20 species studied were able to build up a static pressure of >50Pa, and eight species had convective flow rates higher than 1mlmin-1. There was a clear diel variation, with higher pressures and flows during the day than during the night, when pressures and flows were close to zero...

  16. Uptake of some radionuclides by woody plants growing in the rainforest of Western Ghats in India

    International Nuclear Information System (INIS)

    Manigandan, P.K.; Chandar Shekar, B.

    2014-01-01

    Transfer of the naturally occurring radionuclides 238 U, 232 Th, and 40 K, and the fallout radionuclide 210 Po to different wild plant species in the rainforest of Western Ghats was analyzed. A number of physiologically different plants from the top storey and understorey, such as shrubs and epiphytes, were compared. The concentrations of these radionuclides in the plants and soil were measured using a gamma ray spectrometer and an alpha counter, and were found to vary widely within plants and between species. The soil-plant ratios also varied between species while Elaeocarpus oblongus and epiphytic plants exhibited preferential uptake of these radionuclides. As a result, the dust particles trapped in the root systems of epiphytes could be used as bioindicators of fallout radionuclides in the Western Ghats. - Highlights: • Predominant plants species of the region were selected for analysis. • CR Model was employed to these plants spices. • Two plants were indicated preferential uptake of these radionuclides. • Bioindicator was identified in the Western Ghats Environment

  17. Sapfluxnet: a global database of sap flow measurements to unravel the ecological factors of transpiration regulation in woody plants

    Science.gov (United States)

    Poyatos, Rafael; Martínez-Vilalta, Jordi; Molowny-Horas, Roberto; Steppe, Kathy; Oren, Ram; Katul, Gabriel; Mahecha, Miguel

    2016-04-01

    Plant transpiration is one of the main components of the global water cycle, it controls land energy balance, determines catchment hydrological responses and exerts strong feedbacks on regional and global climate. At the same time, plant productivity, growth and survival are severely constrained by water availability, which is expected to decline in many areas of the world because of global-change driven increases in drought conditions. While global surveys of drought tolerance traits at the organ level are rapidly increasing our knowledge of the diversity in plant functional strategies to cope with drought stress, a whole-plant perspective of drought vulnerability is still lacking. Sap flow measurements using thermal methods have now been applied to measure seasonal patterns in water use and the response of transpiration to environmental drivers across hundreds of species of woody plants worldwide, covering a wide range of climates, soils and stand structural characteristics. Here, we present the first effort to build a global database of sub-daily, tree-level sap flow (SAPFLUXNET) that will be used to improve our understanding of physiological and structural determinants of plant transpiration and to further investigate the role of vegetation in controlling global water balance. We already have the expression of interest of data contributors representing >115 globally distributed sites, > 185 species and > 700 trees, measured over at least one growing season. However, the potential number of available sites and species is probably much higher given that > 2500 sap flow-related papers have been identified in a Scopus literature search conducted in November 2015. We will give an overview of how data collection, harmonisation and quality control procedures are implemented within the project. We will also discuss potential analytical strategies to synthesize hydroclimatic controls on sap flow into biologically meaningful traits related to whole-plant transpiration

  18. Woody plant richness and NDVI response to drought events in Catalonian (northeastern Spain) forests.

    Science.gov (United States)

    Lloret, F; Lobo, A; Estevan, H; Maisongrande, P; Vayreda, J; Terradas, J

    2007-09-01

    The role of species diversity on ecosystem resistance in the face of strong environmental fluctuations has been addressed from both theoretical and experimental viewpoints to reveal a variety of positive and negative relationships. Here we explore empirically the relationship between the richness of forest woody species and canopy resistance to extreme drought episodes. We compare richness data from an extensive forest inventory to a temporal series of satellite imagery that estimated drought impact on forest canopy as NDVI (normalized difference vegetation index) anomalies of the dry summer in 2003 in relation to records of previous years. We considered five different types of forests that are representative of the main climatic and altitudinal gradients of the region, ranging from lowland Mediterranean to mountain boreal-temperate climates. The observed relationship differed among forest types and interacted with the climate, summarised by the Thorntwaite index. In Mediterranean Pinus halepensis forests, NDVI decreased during the drought. This decrease was stronger in forests with lower richness. In Mediterranean evergreen forests of Quercus ilex, drought did not result in an overall NDVI loss, but lower NDVI values were observed in drier localities with lower richness, and in more moist localities with higher number of species. In mountain Pinus sylvestris forests NDVI decreased, mostly due to the drought impact on drier localities, while no relation to species richness was observed. In moist Fagus sylvatica forests, NDVI only decreased in plots with high richness. No effect of drought was observed in the high mountain Pinus uncinata forests. Our results show that a shift on the diversity-stability relationship appears across the regional, climatic gradient. A positive relationship appears in drier localities, supporting a null model where the probability of finding a species able to cope with drier conditions increases with the number of species. However, in

  19. Infrared heater system for warming tropical forest understory plants and soils

    Science.gov (United States)

    Bruce A. Kimball; Aura M. Alonso-Rodríguez; Molly A. Cavaleri; Sasha C. Reed; Grizelle González; Tana E. Wood

    2018-01-01

    The response of tropical forests to global warming is one of the largest uncertainties in predicting the future carbon balance of Earth. To determine the likely effects of elevated temperatures on tropical forest understory plants and soils, as well as other ecosystems, an infrared (IR) heater system was developed to provide in situ warming for the Tropical Responses...

  20. The Scientific Development of the Physiology of Plants in the American Tropics

    Directory of Open Access Journals (Sweden)

    Marco V. Gutiérrez

    2002-06-01

    Full Text Available This paper is a research and journalistic work that summarizes and synthesizes the scientific development of the physiology of plants in the American tropics, also known as the Neotropics. It contains the contributions of numerous biologists interested in the physiology of tropical plants. The fabulous structural and functional diversity of tropical forests is still the major driver of research in this field. Classical physiological work involving tropical plants, such as the discovery of C4 photosynthesis in sugarcane, is invoked to exemplify the historical and current importance of physiological research in the tropics, and its applications in agriculture, forestry and conservation. An historical background describing the early and more recent development of a tradition on the physiological study of tropical plants is followed by a summary of the research conducted on the physiology of tropical crops. Common areas of interest and influence between the fields of crop physiology and plant ecophysiology are identified and exemplified with problems on the environmental physiology of crops like coffee and cassava. The physiology of tropical forest plants is discussed in terms of its contributions to general plant physiological knowledge in areas such as photosynthetic metabolism and plant water relations. Despite the impressive technical advances achieved during the past decade, the importance of continuous development of appropriate instrumentation to study and measure the physiology of plants in situ is stressed. Although the basic metabolic processes that underlie the mechanisms of plant responses to the environment are probably highly conserved and qualitatively similar among tropical and temperate plants, it is also apparent that tropical plants exhibit metabolic peculiarities. These include aspects of photosynthetic metabolism, phloem transport physiology, sensitivity to low temperatures, reproduction, responses to climatic seasonality, and a

  1. Effects of herbivory by Diaprepes abbreviatus (Coleoptera: Curculionidae) larvae on four woody ornamental plant species.

    Science.gov (United States)

    Martin, Cliff G; Mannion, Catharine; Schaffer, Bruce

    2009-06-01

    The hypothesis that herbivory by Diaprepes root weevil larvae reduces leaf gas exchange and biomass was tested on buttonwood (Conocarpus erectus L.), Surinam cherry (Eugenia uniflora L.), mahogany (Swietenia mahagoni Jacq.), and pond apple (Annona glabra L). For Surinam cherry, net CO2 assimilation, transpiration, and stomatal conductance, but not internal CO2 concentration (collectively referred to as leaf gas exchange values), were 7-32% higher in noninfested than infested plants. For buttonwood, all four gas exchange values were 10-54% higher for noninfested than infested plants 3 h after infestation with large, seventh-instar larvae. However, by 4 wk after this infestation, net CO2 assimilation, transpiration, and stomatal conductance, but not internal CO2 concentration, were 11-37% higher for infested than for noninfested plants. For mahogany and pond apple, there were few or no significant differences in leaf gas exchange values between infested and noninfested plants. For all species, mean shoot and root fresh and dry weights were higher for noninfested than infested plants, with the differences most significant for buttonwood (37-85% higher), followed by Surinam cherry (37-143% higher), mahogany (49-84% higher), and pond apple (24-46% higher), which had no significant differences. There were significant differences among plant species in mean head capsule widths, thus larval instars, of larvae recovered from soil with the largest larvae from Surinam cherry (2.59 +/- 0.19 mm) and the smallest from mahogany (2.29 +/- 0.06 mm). Based on differences in leaf gas exchange and plant biomass between infested and noninfested plants of the four species tested, buttonwood and Surinam cherry are the most vulnerable to feeding by Diaprepes larvae followed by mahogany then pond apple.

  2. Concentrations of manganese and iron in some woody and herbs plants

    Directory of Open Access Journals (Sweden)

    Stanković Dragica M.

    2011-01-01

    Full Text Available Heavy metals are the substances that indicate environmental pollution. The plants polluted with heavy metals may endanger natural environment and cause health problems in humans. In our multidisciplinary research of the concentrations of pollutants in forest ecosystems and natural environment in Belgrade, we examined the contents of heavy metals essential for plants but harmful in greater concentrations on a long-term basis. The fact that heavy metals manganese and iron are accumulated in plants to the greatest extent focused our work on determination of the level of concentrations of Mn and Fe in the vegetative parts of 8 plant types on three locations on the Avala Mountain and one location in the centre of the city of Belgrade. The analyses of heavy metals contents in plants were performed by the method of flame atomic absorption spectrophotometry. The examination of the existence of important differences between the average values was performed by implementation of Duncan’s test for the level of significance of 95%. The current contents of heavy metals in plants in the area of the protected natural resource Avala do not represent danger that would presently cause notable damage to forests but show the tendency of the increase of concentrations. Therefore, this issue should be constantly monitored.

  3. Preliminary studies on allelopatic effect of some woody plants on seed germination of rye-grass and tall fescue.

    Science.gov (United States)

    Arouiee, H; Nazdar, T; Mousavi, A

    2010-11-01

    In order to investigation of allelopathic effects of some ornamental trees on seed germination of rye-grass (Lolium prenne) and tall fescue (Festuca arundinaceae), this experiment was conducted in a randomized complete block design with 3 replicates at the laboratory of Horticultural Sciences Department of Ferdowsi University of Mashhad, during 2008. In this research, we studied the effect of aqueous and hydro-alcoholic extracts of Afghanistan pine (Pinus eldarica), arizona cypress (Cupressus arizonica), black locust (Robinia psedue acacia) and box elder (Acer negundo) leaves that prepared in 1:5 ratio on seed germination percent and rate for two grasses. The results showed that all extracts decreased statistically seed germination in compared to control treatment. The highest germination percentage and germination rate of tested grass detected in control treatment. Hydro-alcoholic extracts of all woody plants (15, 30%) were completely inhibited seed germination of rye-grass and tall fescue. Also aqueous extract of arizona cypress was completely inhibited seed germination of tall fescue and had more inhibitory activity than other aqueous extracts on rye-grass. Between aqueous extracts, the highest and lowest seed germination of rye-grass was found in Afghanistan pine and arizona cypress, respectively.

  4. Plant-soil interactions promote co-occurrence of three nonnative woody shrubs.

    Science.gov (United States)

    Kuebbing, Sara E; Classen, Aimée T; Call, Jaime J; Henning, Jeremiah A; Simberloff, Daniel

    2015-08-01

    Ecosystems containing multiple nonnative plant species are common, but mechanisms promoting their co-occurrence are understudied. Plant-soil interactions contribute to the dominance of singleton species in nonnative ranges because many nonnatives experience stronger positive feedbacks relative to co-occurring natives. Plant-soil interactions could impede other nonnatives if an individual nonnative benefits from its soil community to a greater extent than its neighboring nonnatives, as is seen with natives. However, plant-soil interactions could promote nonnative co-occurrence if a nonnative accumulates beneficial soil mutualists that also assist other nonnatives. Here, we use greenhouse and field experiments to ask whether plant-soil interactions (1) promote the codominance of two common nonnative shrubs (Ligustrum sinense and Lonicera maackii) and (2) facilitate the invasion of a less-common nonnative shrub (Rhamnus davurica) in deciduous forests of the southeastern United States. In the greenhouse, we found that two of the nonnatives, L. maackii and R. davurica, performed better in soils conditioned by nonnative shrubs compared to uninvaded forest soils, which. suggests that positive feedbacks among co-occurring nonnative shrubs can promote continued invasion of a site. In both greenhouse and field experiments, we found consistent signals that the codominance of the nonnatives L. sinense and L. maackii may be at least partially explained by the increased growth of L. sinense in L. maackii soils. Overall, significant effects of plant-soil interactions on shrub performance indicate that plant-soil interactions can potentially structure the co-occurrence patterns of these nonnatives.

  5. Elevated temperature is more effective than elevated [CO2 ] in exposing genotypic variation in Telopea speciosissima growth plasticity: implications for woody plant populations under climate change.

    Science.gov (United States)

    Huang, Guomin; Rymer, Paul D; Duan, Honglang; Smith, Renee A; Tissue, David T

    2015-10-01

    Intraspecific variation in phenotypic plasticity is a critical determinant of plant species capacity to cope with climate change. A long-standing hypothesis states that greater levels of environmental variability will select for genotypes with greater phenotypic plasticity. However, few studies have examined how genotypes of woody species originating from contrasting environments respond to multiple climate change factors. Here, we investigated the main and interactive effects of elevated [CO2 ] (CE ) and elevated temperature (TE ) on growth and physiology of Coastal (warmer, less variable temperature environment) and Upland (cooler, more variable temperature environment) genotypes of an Australian woody species Telopea speciosissima. Both genotypes were positively responsive to CE (35% and 29% increase in whole-plant dry mass and leaf area, respectively), but only the Coastal genotype exhibited positive growth responses to TE . We found that the Coastal genotype exhibited greater growth response to TE (47% and 85% increase in whole-plant dry mass and leaf area, respectively) when compared with the Upland genotype (no change in dry mass or leaf area). No intraspecific variation in physiological plasticity was detected under CE or TE , and the interactive effects of CE and TE on intraspecific variation in phenotypic plasticity were also largely absent. Overall, TE was a more effective climate factor than CE in exposing genotypic variation in our woody species. Our results contradict the paradigm that genotypes from more variable climates will exhibit greater phenotypic plasticity in future climate regimes. © 2015 John Wiley & Sons Ltd.

  6. A Global Database of Field-observed Leaf Area Index in Woody Plant Species, 1932-2011

    Data.gov (United States)

    National Aeronautics and Space Administration — This data set provides global leaf area index (LAI) values for woody species. The data are a compilation of field-observed data from 1,216 locations obtained from...

  7. A Global Database of Field-observed Leaf Area Index in Woody Plant Species, 1932-2011

    Data.gov (United States)

    National Aeronautics and Space Administration — ABSTRACT: This data set provides global leaf area index (LAI) values for woody species. The data are a compilation of field-observed data from 1,216 locations...

  8. Iron Availability in Tropical Soils and Iron Uptake by Plants

    Directory of Open Access Journals (Sweden)

    Guilherme Furlan Mielki

    Full Text Available ABSTRACT Given the increase in crop yields and the expansion of agriculture in low fertility soils, deficiency of micronutrients, such as iron, in plants grown in tropical soils has been observed. The aim of this study was to evaluate Fe availability and Fe uptake by corn (Zea mays L. plants in 13 different soils, at two depths. Iron was extracted by Mehlich-1, Mehlich-3, and CaCl2 (Fe-CC and was fractionated in forms related to low (Feo and high (Fed crystallinity pedogenic oxyhydroxides, and organic matter (Fep using ammonium oxalate, dithionite-citrate, and sodium pyrophosphate, respectively. In order to relate Fe availability to soil properties and plant growth, an experiment was carried out in a semi-hydroponic system in which part of the roots developed in a nutrient solution (without Fe and part in the soil (the only source of Fe. Forty-five days after seeding, we quantified shoot dry matter and leaf Fe concentration and content. Fed levels were high, from 5 to 132 g kg-1, and Feo and Fe-CC levels were low, indicating the predominance of Fe as crystalline oxyhydroxides and a low content of Fe readily available to plants. The extraction solutions showed significant correlations with various soil properties, many common to both, indicating that they act similarly. The correlation between the Mehlich-1 and Mehlich-3 extraction solutions was highly significant. However, these two extraction methods were inefficient in predicting Fe availability to plants. There was a positive correlation between dry matter and Fe levels in plant shoots, even within the ranges considered adequate in the soil and in the plant. Dry matter production and leaf Fe concentration and content were positively correlated with Fep concentration, indicating that the Fe fraction related to soil organic matter most contributes to Fe availability to plants.

  9. Woody plant roots fail to penetrate a clay-lined landfill: Managment implications

    Science.gov (United States)

    Robinson, George R.; Handel, Steven N.

    1995-01-01

    In many locations, regulatory agencies do not permit tree planting above landfills that are sealed with a capping clay, because roots might penetrate the clay barrier and expose landfill contents to leaching. We find, however, no empirical or theoretical basis for this restriction, and instead hypothesize that plant roots of any kind are incapable of penetrating the dense clays used to seal landfills. As a test, we excavated 30 trees and shrubs, of 12 species, growing over a clay-lined municipal sanitary landfill on Staten Island, New York. The landfill had been closed for seven years, and featured a very shallow (10 to 30-cm) soil layer over a 45-cm layer of compacted grey marl (Woodbury series) clay. The test plants had invaded naturally from nearby forests. All plants examined—including trees as tall as 6 m—had extremely shallow root plates, with deformed tap roots that grew entirely above and parallel to the clay layer. Only occasional stubby feeder roots were found in the top 1 cm of clay, and in clay cracks at depths to 6 cm, indicating that the primary impediment to root growth was physical, although both clay and the overlying soil were highly acidic. These results, if confirmed by experimental research should lead to increased options for the end use of many closed sanitary landfills.

  10. Forest Carbon Stocks in Woody Plants of Arba Minch Ground Water ...

    African Journals Online (AJOL)

    The role of forests in mitigating the effect of climate change depends on the carbon sequestration potential and management. This study was conducted to estimate the carbon stock and its variation along environmental gradients in Arba Minch Ground Water Forest. The data was collected from the field by measuring plants ...

  11. Seasonal and species-specific response of VOC emissions by Mediterranean woody plant to elevated ozone concentrations

    Energy Technology Data Exchange (ETDEWEB)

    Llusia, J.; Penuelas, J. [Universitat Autonoma de Barcelona (Spain). Unitat Ecofisiologia CSIC-CEAB-CREAF; Gimeno, R.S. [CIEMAT, Madrid (Spain). Ecotoxicologia de la Contaminacion Atmosferica

    2002-08-01

    Although certain factors controlling plant emission rates of volatile organic compounds (VOCs) are reasonably well understood, the influence of elevated ozone concentrations as abiotic stress is mostly unknown. Therefore, we studied the effects of ozone concentrations on seasonal biogenic volatile organic compound (BVOC) emissions by different Mediterranean plant species in open top chambers (OTC). Three ozone treatments were established: filtered air (F), non-filtered air (NF), and fumigated air (NF+) adding 40 nl l{sup -1} of ozone over NF. We studied the response of VOC emission in saplings of four Mediterranean woody plant species and subspecies: Ceratonia siliqua L., Olea europaea L., Quercus ilex spp. ilex L., and Quercus ilex spp. rotundifolia L. as representative of natural Mediterranean vegetation. No visible symptoms were detected on the leaves. No significant effect was found on net photosynthetic rates or stomatal conductance except for an increase in net photosynthetic rates in Quercus ilex ilex in spring and summer and an overall slight increase in Quercus ilex rotundifolia. Emissions of the total VOCs from Ceratonia siliqua in summer, and from Olea europaea and Quercus ilex rotundifolia in spring increased in ozone fumigated OTC in comparison with F or NF OTC. Decreased emissions were found in Quercus ilex rotundifolia in summer. There were no significant differences between ozone fumigation treatments for the other plant species and seasons. When considering particular VOCs, the results were also variable among species and time of the year. While {alpha}-pinene emissions decreased with ozone fumigation in Olea europaea, {alpha}-pinene and limonene emissions increased in Quercus ilex ilex. The responses of these particular VOCs did not always match the responses of total VOCs. In spite of this strong variability, when considering overall annual data for all species and seasons, there were increased net photosynthetic rates (37%) and limonene (95

  12. Seasonal and species-specific response of VOC emissions by Mediterranean woody plant to elevated ozone concentrations

    Science.gov (United States)

    Llusià, J.; Peñuelas, J.; Gimeno, B. S.

    Although certain factors controlling plant emission rates of volatile organic compounds (VOCs) are reasonably well understood, the influence of elevated ozone concentrations as abiotic stress is mostly unknown. Therefore, we studied the effects of ozone concentrations on seasonal biogenic volatile organic compound (BVOC) emissions by different Mediterranean plant species in open top chambers (OTC). Three ozone treatments were established: filtered air (F), non-filtered air (NF), and fumigated air (NF+) adding 40 nl l -1 of ozone over NF. We studied the response of VOC emission in saplings of four Mediterranean woody plant species and subspecies: Ceratonia siliqua L., Olea europaea L., Quercus ilex spp. ilex L., and Quercus ilex spp. rotundifolia L. as representative of natural Mediterranean vegetation. No visible symptoms were detected on the leaves. No significant effect was found on net photosynthetic rates or stomatal conductance except for an increase in net photosynthetic rates in Quercus ilex ilex in spring and summer and an overall slight increase in Quercus ilex rotundifolia. Emissions of the total VOCs from Ceratonia siliqua in summer, and from Olea europaea and Quercus ilex rotundifolia in spring increased in ozone fumigated OTC in comparison with F or NF OTC. Decreased emissions were found in Quercus ilex rotundifolia in summer. There were no significant differences between ozone fumigation treatments for the other plant species and seasons. When considering particular VOCs, the results were also variable among species and time of the year. While α-pinene emissions decreased with ozone fumigation in Olea europaea, α-pinene and limonene emissions increased in Quercus ilex ilex. The responses of these particular VOCs did not always match the responses of total VOCs. In spite of this strong variability, when considering overall annual data for all species and seasons, there were increased net photosynthetic rates (37%) and limonene (95%) and total VOC (45

  13. Impact of anthropogenic forest contamination on radioresistance of woody plant seed

    International Nuclear Information System (INIS)

    Yushkov, P.I.

    2004-01-01

    Radioresistance of seeds of bay willow (Salix pentandra L.) and great sallow willow (Salix caprea L.) from forests chronically affected and non-affected by acidic (SO 2 , NO x , HF, etc.) industries has been studied and compared. Bay willow seeds of 6 harvests showed no difference in radioresistance. However, seeds of both species manifested strong synchronous variability in resistance to preplant exposure. Also, no influence was observed of mother plant gas content on great sallow willow seeds of different harvests. Data obtained confirm similar results of previous studies conducted by the author (1987) to identify the impact of plant gas content on radioresistance of seeds and seedlings of pine (Pinus sylvestris L.) and birch (Betula verrucosa Erh.). (author)

  14. Woody-plant ecosystems under climate change and air pollution-response consistencies across zonobiomes?

    Science.gov (United States)

    Matyssek, R; Kozovits, A R; Wieser, G; King, J; Rennenberg, H

    2017-06-01

    Forests store the largest terrestrial pools of carbon (C), helping to stabilize the global climate system, yet are threatened by climate change (CC) and associated air pollution (AP, highlighting ozone (O3) and nitrogen oxides (NOx)). We adopt the perspective that CC-AP drivers and physiological impacts are universal, resulting in consistent stress responses of forest ecosystems across zonobiomes. Evidence supporting this viewpoint is presented from the literature on ecosystem gross/net primary productivity and water cycling. Responses to CC-AP are compared across evergreen/deciduous foliage types, discussing implications of nutrition and resource turnover at tree and ecosystem scales. The availability of data is extremely uneven across zonobiomes, yet unifying patterns of ecosystem response are discernable. Ecosystem warming results in trade-offs between respiration and biomass production, affecting high elevation forests more than in the lowland tropics and low-elevation temperate zone. Resilience to drought is modulated by tree size and species richness. Elevated O3 tends to counteract stimulation by elevated carbon dioxide (CO2). Biotic stress and genomic structure ultimately determine ecosystem responsiveness. Aggrading early- rather than mature late-successional communities respond to CO2 enhancement, whereas O3 affects North American and Eurasian tree species consistently under free-air fumigation. Insect herbivory is exacerbated by CC-AP in biome-specific ways. Rhizosphere responses reflect similar stand-level nutritional dynamics across zonobiomes, but are modulated by differences in tree-soil nutrient cycling between deciduous and evergreen systems, and natural versus anthropogenic nitrogen (N) oversupply. The hypothesis of consistency of forest responses to interacting CC-AP is supported by currently available data, establishing the precedent for a global network of long-term coordinated research sites across zonobiomes to simultaneously advance both

  15. Effects of anabolic and catabolic nutrients on woody plant encroachment after long-term experimental fertilization in a South African savanna.

    Directory of Open Access Journals (Sweden)

    Anthony J Mills

    Full Text Available The causes of the worldwide problem of encroachment of woody plants into grassy vegetation are elusive. The effects of soil nutrients on competition between herbaceous and woody plants in various landscapes are particularly poorly understood. A long-term experiment of 60 plots in a South African savanna, comprising annual applications of ammonium sulphate (146-1166 kg ha-1 yr-1 and superphosphate (233-466 kg ha-1 yr-1 over three decades, and subsequent passive protection over another three decades, during which indigenous trees encroached on different plots to extremely variable degrees, provided an opportunity to investigate relationships between soil properties and woody encroachment. All topsoils were analysed for pH, acidity, EC, water-dispersible clay, Na, Mg, K, Ca, P, S, C, N, NH4, NO3, B, Mn, Cu and Zn. Applications of ammonium sulphate (AS, but not superphosphate (SP, greatly constrained tree abundance relative to control plots. Differences between control plots and plots that had received maximal AS application were particularly marked (16.3 ± 5.7 versus 1.2 ± 0.8 trees per plot. Soil properties most affected by AS applications included pH (H2O (control to maximal AS application: 6.4 ± 0.1 to 5.1 ± 0.2, pH (KCl (5.5 ± 0.2 to 4.0 ± 0.1, acidity (0.7 ± 0.1 to 2.6 ± 0.3 cmol kg-1, acid saturation (8 ± 2 to 40 ± 5%, Mg (386 ± 25 to 143 ± 15 mg kg-1, Ca (1022 ± 180 to 322 ± 14 mg kg-1, Mn (314 ± 11 to 118 ± 9 mg kg-1, Cu (3.6 ± 0.3 to 2.3 ± 0.2 mg kg-1 and Zn (6.6 ± 0.4 to 3.7 ± 0.4 mg kg-1. Magnesium, B, Mn and Cu were identified using principal component analysis, boundary line analysis and Kruskal-Wallis rank sum tests as the nutrients most likely to be affecting tree abundance. The ratio Mn/Cu was most related to tree abundance across the experiment, supporting the hypothesis that competition between herbaceous and woody plants depends on the availability of anabolic relative to catabolic nutrients. These findings

  16. Genetic manipulation of woody plants and its applications. Rinboku no idenshi sosa to sono oyo

    Energy Technology Data Exchange (ETDEWEB)

    Ebinuma, H. (Jujo Paper Co. Ltd., Tokyo (Japan))

    1992-06-01

    The advance of plant biotechnology has been further accelerated by the development of the new epoch-making technique typified by the DNA amplification using the PCR (polymerase chain reaction) method. In the application of plant biotechnology to trees, the introduction of useful genes into genetically elite trees and short-period mass propagation of recombinants by micropropagation are considered to be rational strategies. In the utilization of recombinants, non-edible industrial product materials such as trees are considered to pass the safety standards more easily and also to be profitable. This paper discusses the possibilities of tree recombinants, the imparting of disease-resistance to elite trees and the biosynthetic control of lignin. The paper introduces a topic that the imparting of disease-resistance to elite trees is in a stage of transference to experiments of recombinants in a closed-system greenhouse by the construction of the crown gall resistant gene and the establishment of the gene introduction system into crossed populus sieboldii miquel. 19 refs., 4 figs.

  17. [Methanotrophs and methylobacteria are found in woody plant tissues within a winter period].

    Science.gov (United States)

    Doronina, N V; Ivanova, E G; Suzina, N F; Trotsenko, Iu A

    2004-01-01

    Samples of tree seeds, buds, and needles collected within a winter period at ambient temperatures from -11 to -17 degrees C were analyzed for the presence of methylotrophic microflora. Thin sections of blue spruce needles were found to contain bacteria morphologically close to pink-pigmented methylobacteria. The methylobacteria that were isolated in pure cultures from samples of linden seeds and buds, pine and blue spruce needles, as well as of lilac, maple, and apple buds, were classified into the genera Methylobacterium and Paracoccus based on the data of morphological studies, enzyme assay, and DNA-DNA hybridization analysis. The methanotrophs that were isolated in pure cultures from samples of linden buds and blue spruce needles were identified into the genus Methylocystis based on the data of morphological studies, enzyme assay, DNA-DNA hybridization, and the phylogenetic analysis of the particulate methane monooxygenase gene pmoA sequences. The inference is made that aerobic methylotrophic bacteria are permanently associated with plants. At the beginning of the vegetative period in spring, the phyllosphere of coniferous and deciduous trees is colonized by the methylotrophic bacteria that have wintered inside plant tissues.

  18. Genome analysis of Hibiscus syriacus provides insights of polyploidization and indeterminate flowering in woody plants.

    Science.gov (United States)

    Kim, Yong-Min; Kim, Seungill; Koo, Namjin; Shin, Ah-Young; Yeom, Seon-In; Seo, Eunyoung; Park, Seong-Jin; Kang, Won-Hee; Kim, Myung-Shin; Park, Jieun; Jang, Insu; Kim, Pan-Gyu; Byeon, Iksu; Kim, Min-Seo; Choi, JinHyuk; Ko, Gunhwan; Hwang, JiHye; Yang, Tae-Jin; Choi, Sang-Bong; Lee, Je Min; Lim, Ki-Byung; Lee, Jungho; Choi, Ik-Young; Park, Beom-Seok; Kwon, Suk-Yoon; Choi, Doil; Kim, Ryan W

    2017-02-01

    Hibiscus syriacus (L.) (rose of Sharon) is one of the most widespread garden shrubs in the world. We report a draft of the H. syriacus genome comprised of a 1.75 Gb assembly that covers 92% of the genome with only 1.7% (33 Mb) gap sequences. Predicted gene modeling detected 87,603 genes, mostly supported by deep RNA sequencing data. To define gene family distribution among relatives of H. syriacus, orthologous gene sets containing 164,660 genes in 21,472 clusters were identified by OrthoMCL analysis of five plant species, including H. syriacus, Arabidopsis thaliana, Gossypium raimondii, Theobroma cacao and Amborella trichopoda. We inferred their evolutionary relationships based on divergence times among Malvaceae plant genes and found that gene families involved in flowering regulation and disease resistance were more highly divergent and expanded in H. syriacus than in its close relatives, G. raimondii (DD) and T. cacao. Clustered gene families and gene collinearity analysis revealed that two recent rounds of whole-genome duplication were followed by diploidization of the H. syriacus genome after speciation. Copy number variation and phylogenetic divergence indicates that WGDs and subsequent diploidization led to unequal duplication and deletion of flowering-related genes in H. syriacus and may affect its unique floral morphology. © The Author 2016. Published by Oxford University Press on behalf of Kazusa DNA Research Institute.

  19. Introduction and domestication of woody plants for sustainable agriculture in desert areas

    Science.gov (United States)

    Shelef, Oren; Soloway, Elaine; Rachmilevitch, Shimon

    2014-05-01

    High radiation in hot deserts results in high salinity, especially in irrigated fields. Whenever not treated properly, this salinization may harm crops and eventually bring to soil destruction, field abandonment, or literally desertification. Furthermore, the range of crops that can be grown commercially in hot deserts is limited (Nerd et al. 1990). With the globalization of the last century, Introduction of exotic species for commercial use became more accessible. However, these attempts may involve extreme land changes including establishment of potential invasive species. Therefore domestication of native species should be preferred rather than introduction of exotics. In the last six years we did first steps of domesticating several native species, searching for commercial potential (pharmaceutics, food, biomass for energy and desalination of constructed wetlands). We studied aspects of desert plant physiology in drought and saline conditions. We wish to share the knowledge we gained regarding the physiology and commercial potential of the following desert plant species: 1) Bassia indica is an annual halophyte. We proposed to use it for salt phytoremediation in constructed wetlands for wastewater treatment and as feed for livestock; 2) Commiphora gileadensis is considered as the balm tree of Judea, praised for its use as holy oil and in perfumes but also considered as a cure for many diseases. C. gileadensis today grows naturally in southwest Arabia and Somaliland. We found anti-proliferative and apoptotic effect of C. gileadensis extracts on several human cancer cells. Ben Gurion University of the Negev has patented these findings. 3) Artemisia sieberi and A. judaica are both known for various therapeutic traits. While studying effects of irrigation intensity on these traits, some allopathic characters were discovered. 4) Fichus palmate disappeared from Israel, but remind in neighbouring Jordan and Egypt. This tree may serve as a robust stand for fig

  20. Woody plants diversity and type of vegetation in non cultivated plain of Moutourwa, Far-North, Cameroon

    Directory of Open Access Journals (Sweden)

    Gilbert Todou

    2016-12-01

    Full Text Available In order to valorize the wild vegetal resources for the efficient conservation and sustainable use in sahelo-sudanian zone in Cameroon, a study of non cultivated plain of Moutourwa was carry out to assess the floristic richness, the specific diversity and the type of vegetation. The inventory of all trees and shrubs (dbh ? 2.5 cm and the determination of the vegetation cover were done in five linear transects (20 m × 1000 m. In total, 27 families, 54 genera and 75 species were found. Caesalpinaceae is the most abundant family that relative abundance (pi*100 is 34.41%, the most abundant genus was Piliostigma (pi*100 = 30.66% and the most represented species was Piliostigma reticulatum (pi*100 = 29.56%; D = 53.6 stems/ha. The Simpson index (E= 0.89, the Shannon index (H= 3.2 and the equitability index of Pielou (J= 0.74 indicated that there were moderate diversity with more or less equitable species. The wild fruits species were numerous (pi*100 = 32.76%; D = 59.7 stems/ha. A. senegalensis is was the most represented (pi*100 = 9.04 ; D = 16.4 followed by Hexalobus monopetalus (pi*100 = 5.16 ; D = 9.4 and Balanites aegyptiaca (pi*100 = 3.69 ; D = 6.7. These results contribute efficaciously to valorize the wild vegetal resources for efficient conservation and sustainable use. Keywords: Woody plants diversity, conservation, sustainable use, sahelo-sudanian, Moutourwa

  1. Does the edge effect influence plant community structure in a tropical dry forest? O efeito de borda influencia a estrutura da comunidade vegetal em uma floresta tropical seca?

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    Diogo Gallo Oliveira

    2013-04-01

    Full Text Available Edge effects are considered a key factor in regulating the structure of plant communities in different ecosystems. However, regardless to few studies, edge influence does not seem to be decisive in semiarid regions such as the Brazilian tropical dry forest known as Caatinga but this issue remains inconclusive. The present study tests the null hypothesis that the plant community of shrubs and trees does not change in its structure due to edge effects. Twenty-four plots (20 x 20 m were set up in a fragment of Caatinga, in which 12 plots were in the forest edges and 12 plots were inside the fragment. Tree richness, abundance and species composition did not differ between edge and interior plots. The results of this study are in agreement with the pattern previously found for semiarid environments and contrasts with previous results obtained in different environments such as Rainforests, Savanna and Forest of Araucaria, which indicate abrupt differences between the border and interior of the plant communities in these ecosystems, and suggest that the community of woody plants of the Caatinga is not ecologically affected by the presence of edges.Efeitos de borda são considerados fator-chave na regulação da estrutura de comunidades vegetais em diferentes ecossistemas. Entretanto, apesar dos poucos estudos relacionados, o efeito de borda parece não ser determinante em regiões semiáridas, como a floresta tropical seca brasileira, conhecida como Caatinga. Este estudo testou a hipótese nula de que a comunidade vegetal arbustivo-arbórea não sofre alterações em sua estrutura, riqueza e composição devido ao efeito de borda. Foram instaladas 24 parcelas (20 x 20 m em um fragmento de Caatinga arbórea, sendo 12 parcelas na borda do fragmento e 12 parcelas no seu interior. A riqueza, abundância e composição das espécies não diferiram estatisticamente entre as parcelas de borda e interior. Os resultados deste estudo corroboram um possível padr

  2. Fractured Epikarst Bedrock as Water Source for Woody Plants in Savanna

    Science.gov (United States)

    Schwinning, S.; Goodsheller, K. R.; Schwartz, B. F.

    2010-12-01

    Study of the soil-vegetation-atmosphere system has been overwhelmingly dominated by systems with deep soils, yet large portions of the world are characterized by shallow soils underlain by fractured bedrock. In these systems, fractured bedrock may provide significant water storage, but we know little about the function of fractured bedrock as a water source for plants. In this study we examined the water use of three co-dominant tree species on the eastern rim of the karstic Edwards Plateau where the soil is extremely rocky, only 20 -30 cm thick, and overlies a well-developed epikarst. We used Granier sap flow sensors to estimate changes in sapflow velocity with the onset of summer drought. Simultaneously, we measured precipitation inputs and drip rates in a shallow cave below the field site. Precipitation, stem and drip water were also periodically sampled for stable isotope analysis to match stem water with potential source waters. The year of the study, 2009, was characterized by extreme drought conditions developing during summer. Sap flow rates began to decline in mid-May for all three species, but there were distinct species differences in the development of water stress: live oak (Quercus fusiformis) was the first to show significant loss of transpiration, reaching minimal sap flow values by early June. Cedar elm (Ulmus crassifolia) reached minimal sap flow values by early July, while Ashe juniper’s (Juniperus ashei) loss of transpiration was very gradual, continuing to decline until early August. The isotope ratios of hydrogen and oxygen in water were not significantly different between species, suggesting that root development and water uptake was similarly constrained for the three species. In summer, all stem water isotope ratios were enriched relative to precipitation, while all drip waters coincided with the local meteoric water line. This suggests that tree water sources were relatively shallow and water draining out of the root zone did not have a

  3. Frugivory and dispersal of Faramea cyanea (Rubiaceae in Cerrado woody plant formations

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    Melo C.

    2003-01-01

    Full Text Available The objective of this study was to observe and compare the community of birds that utilize the tree species Faramea cyanea, in contiguous areas of cerradão and gallery forest, and also to characterize the behavioral patterns of the birds. The study was carried out in the Panga Ecological Station (Uberlândia, Minas Gerais State, in April and May 2001. Nine individuals of F. cyanea were observed in periods between 06:45-11:30 h for a total of 44.5 hours. There were 204 visits by 13 bird species. Tyrannidae was the most represented family (five species and Turdidae, the most frequent (72.1% of visits. The number of consumed fruits was correlated with the permanence time on the plant. There was no significant difference between the two forests habitats, in terms of foraging tactics or fruit consumption strategies. In spite of the predominance of omnivorous birds (89.5% in both habitats, the swallower strategy (84.2% indicates high seed dispersal potential. Antilophia galeata, a frugivorous bird, presented the greatest rate of consumed fruits per minute in both gallery forest (2.15 and cerradão (1.06.

  4. Frugivory and dispersal of Faramea cyanea (Rubiaceae in Cerrado woody plant formations

    Directory of Open Access Journals (Sweden)

    C. Melo

    Full Text Available The objective of this study was to observe and compare the community of birds that utilize the tree species Faramea cyanea, in contiguous areas of cerradão and gallery forest, and also to characterize the behavioral patterns of the birds. The study was carried out in the Panga Ecological Station (Uberlândia, Minas Gerais State, in April and May 2001. Nine individuals of F. cyanea were observed in periods between 06:45-11:30 h for a total of 44.5 hours. There were 204 visits by 13 bird species. Tyrannidae was the most represented family (five species and Turdidae, the most frequent (72.1% of visits. The number of consumed fruits was correlated with the permanence time on the plant. There was no significant difference between the two forests habitats, in terms of foraging tactics or fruit consumption strategies. In spite of the predominance of omnivorous birds (89.5% in both habitats, the swallower strategy (84.2% indicates high seed dispersal potential. Antilophia galeata, a frugivorous bird, presented the greatest rate of consumed fruits per minute in both gallery forest (2.15 and cerradão (1.06.

  5. Patterns of woody plant species diversity in Lebanon as affected by climatic and soil properties

    International Nuclear Information System (INIS)

    Zahreddine, H.; Barker, D.; Struve, D.; Martin, F.; Quigley, M.; Sleem, K.

    2007-01-01

    Lebanese biodiversity is threatened by tourist and urban development, political instability, over-collection of medicinal and aromatic plants, lack of compliance to the regulations prohibiting over-exploitation from the wild, over-grazing and forest fires. A large number of the native species have unexplored economic potential for either medicinal or ornamental use. One way to preserve these species is by propagation and reintroduction into appropriate habitats. However, this requires an understanding of the species biology and environment. The relationship of nine species to the soil and climatic conditions in eight sites along an altitudinal gradient was studied. Individual species were counted and identified within transects at each site. Climatic data were collected and soil samples were taken and analyzed for soil texture, soil pH, EC, CaCO3, organic matter content and the following nutrients: Ca, Mn, Na, Fe, P, K, Cu, Mg, and Zn. Each ecosystem had a unique environment that could be described using the first two factors (70.3 % of variation) in a Factor Analysis of the six most important variables. Some species densities were affected by soil conditions (the first factor) while climatic conditions (the second factor) explained the densities of other species. Recommendations are made for the in-situ and ex-situ preservations of the nine species and their ecosystems.(author)

  6. Accumulation and long term behavior of radiocesium in tropical plants

    International Nuclear Information System (INIS)

    Anjos, R.M.; Carvalho, C.; Mosquera, B.; Macario, K.; Veiga, R.; Sanches, N.; Bastos, J.; Saavedra, R.; Iguatemy, M.

    2006-01-01

    Full text of publication follows: In recent years, there has been a growing interest in the evaluation of nutrient fluxes and radioactive contaminants in forest and agricultural ecosystems. Several studies on forest ecosystems have been carried out, mostly in Europe, after the Chernobyl accident. Japanese forest sites and native plant species of the Marshall Islands have also been extensively investigated. These studies have been used for various purposes, including the development of models for predicting plant concentrations from soil concentration measurements or the long term of dietary contamination by radiocesium following a fallout nuclear. Cesium is an alkali metal just like potassium and its behavior in nature, as well as in the human body, is similar to that of potassium. Uptake of 137 Cs from contaminated soil represents a significant pathway of human radiation exposure, either due to the direct consumption of cereals, fruits and vegetables or, indirectly, following consumption of milk and meat from animals fed on contaminated vegetable matter. The decline of 137 Cs levels as function of time of fruit trees is of interest given its long life in the field. Therefore, the cesium behavior is important in the design of management strategies to mitigate any negative health effects of radioactivity on the environment. It is also important to apply the current knowledge of the transport and distribution of salts derived from forest ecosystems in agricultural ecosystems, especially for tropical fruit trees. So far, in the South hemisphere there have been only a few studies on this subject, without conclusive results. With this aim, the Laboratory of Radioecology (L.A.R.A.) of the 'Universidade Federal Fluminense' has been performing analyzes of 137 Cs and 40 K concentrations in several tropical plants (guava, mango, avocado, pomegranate, papaya, manioc and chili pepper trees) in order to determine the accumulation of these radionuclides throughout these trees

  7. Accumulation and long term behavior of radiocesium in tropical plants

    Energy Technology Data Exchange (ETDEWEB)

    Anjos, R.M.; Carvalho, C.; Mosquera, B.; Macario, K.; Veiga, R.; Sanches, N.; Bastos, J.; Saavedra, R.; Iguatemy, M. [Universidade Federal Fluminense, Niteroi (Brazil)

    2006-07-01

    Full text of publication follows: In recent years, there has been a growing interest in the evaluation of nutrient fluxes and radioactive contaminants in forest and agricultural ecosystems. Several studies on forest ecosystems have been carried out, mostly in Europe, after the Chernobyl accident. Japanese forest sites and native plant species of the Marshall Islands have also been extensively investigated. These studies have been used for various purposes, including the development of models for predicting plant concentrations from soil concentration measurements or the long term of dietary contamination by radiocesium following a fallout nuclear. Cesium is an alkali metal just like potassium and its behavior in nature, as well as in the human body, is similar to that of potassium. Uptake of 137 Cs from contaminated soil represents a significant pathway of human radiation exposure, either due to the direct consumption of cereals, fruits and vegetables or, indirectly, following consumption of milk and meat from animals fed on contaminated vegetable matter. The decline of 137 Cs levels as function of time of fruit trees is of interest given its long life in the field. Therefore, the cesium behavior is important in the design of management strategies to mitigate any negative health effects of radioactivity on the environment. It is also important to apply the current knowledge of the transport and distribution of salts derived from forest ecosystems in agricultural ecosystems, especially for tropical fruit trees. So far, in the South hemisphere there have been only a few studies on this subject, without conclusive results. With this aim, the Laboratory of Radioecology (L.A.R.A.) of the Universidade Federal Fluminense has been performing analyzes of 137 Cs and 40 K concentrations in several tropical plants (guava, mango, avocado, pomegranate, papaya, manioc and chili pepper trees) in order to determine the accumulation of these radionuclides throughout these trees and

  8. Influence of arbuscular mycorrhizal fungi inoculum produced on-farm and phosphorus on growth and nutrition of native woody plant species from Brazil

    Directory of Open Access Journals (Sweden)

    Luis Claudio Goetten

    2016-03-01

    Full Text Available Mycorrhizal fungus inoculum produced on-farm can be used during production of woody plant seedlings to reduce costs associated with purchase of commercial inoculant and fertilization. This study aimed to test the efficiency of a mycorrhizal inoculant produced on-farm to promote growth and nutrition of woody species in combination with different levels of phosphorus. Plants were submitted to different treatments of phosphorus (0, 40 and 80 mg P/dm3 and mycorrhizal inoculation (uninoculated, and inoculation with Rhizophagus clarus [Rc] or Claroideoglomus etunicatum [Ce]. Species included were Luehea divaricata, Centrolobium robustum, Schinus terebinthifolius, Garcinia gardneriana, Cedrella fissilis, and Lafoensia pacari. The inoculum was produced using the on-farm methodology. Mycorrhizal colonization of plants inoculated with Rc and Ce ranged from 44.8 to 74.8%, except forGarcinia gardneriana. Inoculation treatment increased plant height and stem diameter of Luehea divaricata, Centrolobium robustum and Cedrella fissilis while phosphorus, inoculation and the interaction affected these parameters for G. gardneriana and Lafoensia pacari. Shoot biomass increased significantly with inoculation treatment in four species. For most species, mycorrhizal fungus inoculation and the addition of phosphorus increased the shoot phosphorus content. Mycorrhizal fungus inoculum produced on-farm successfully colonized tree seedlings and improved growth and/or nutrition under nursery conditions, producing seedlings useful for revegetation of degraded lands.

  9. Linking plant hydraulics and beta diversity in tropical forests

    Energy Technology Data Exchange (ETDEWEB)

    Christoffersen, Bradley [Earth and Environmental Sciences, Los Alamos National Laboratory, Los Alamos NM 87545 USA; Meir, Patrick [School of GeoSciences, University of Edinburgh, Edinburgh EH9 3FE UK; Research School of Biology, Australian National University, Canberra ACT 2601 Australia; McDowell, Nate G. [Pacific Northwest National Laboratory, Richland WA 99352 USA

    2017-05-31

    In tropical forests, studies of xylem traits governing water transport through plants, or ‘hydraulic architecture’ (Tyree et al., 1991), and changes in species composition across environmental gradients, or ‘beta diversity’ (Gentry, 1988; Ackerly & Cornwell, 2007), have progressedmostly in parallel until recently (Hao et al., 2008; Bartlett et al., 2016). In this issue of New Phytologist, Cosme et al. (pp. 000–5 000) present a timely contribution to the intersection of plant hydraulic architecture (HA) with trait-based community ecology. Building on previous biogeographical work that demonstrated shifts in species composition (beta diversity) across a gradient from valleys to plateaus in central Amazonia (Schietti et al., 2014), Cosme et al. explore how variation in HA might underpin this sorting, sampling pairs of congeneric species restrictedmostly to either plateau or valley habitats. Valley species had significantly lower wood density and higher hydraulically-weighted vessel diameter and vessel area. By contrast, trees with some of the largest hydraulically-weighted vessel diameters existed in tall, deciduous plateau species, while the leaf: sapwood area ratio decreased with height in valley but not plateau species. These intriguing results suggest that species differentiation in water transport traits mediate edaphic filtering along the valley-toplateau gradient, in contrast to previous work where wood mechanical support mediated valley-to-plateau environmental filtering (Fortunel et al., 2014).

  10. Sparrow nest survival in relation to prescribed fire and woody plant invasion in a northern mixed-grass prairie

    Science.gov (United States)

    Murphy, Robert K.; Shaffer, Terry L.; Grant, Todd A.; Derrig, James L.; Rubin, Cory S.; Kerns, Courtney K.

    2017-01-01

    Prescribed fire is used to reverse invasion by woody vegetation on grasslands, but managers often are uncertain whether influences of shrub and tree reduction outweigh potential effects of fire on nest survival of grassland birds. During the 2001–2003 breeding seasons, we examined relationships of prescribed fire and woody vegetation to nest survival of clay-colored sparrow (Spizella pallida) and Savannah sparrow (Passerculus sandwichensis) in mixed-grass prairie at Des Lacs National Wildlife Refuge in northwestern North Dakota, USA. We assessed relationships of nest survival to 1) recent fire history, in terms of number of breeding seasons (2, 3, or 4–5) since the last prescribed fire, and 2) prevalence of trees and tall (>1.5 m) shrubs in the landscape and of low (≤1.5 m) shrubs within 5 m of nests. Nest survival of both species exhibited distinct patterns related to age of the nest and day of year, but bore no relationship to fire history. Survival of clay-colored sparrow nests declined as the amount of trees and tall shrubs within 100 m increased, but we found no relationship to suggest nest parasitism by brown-headed cowbirds (Molothrus ater) as an underlying mechanism. We found little evidence linking nest survival of Savannah sparrow to woody vegetation. Our results suggest that fire can be used to restore northern mixed-grass prairies without adversely affecting nest survival of ≥2 widespread passerine species. Survival of nests of clay-colored sparrow may increase when tall woody cover is reduced by fire. Our data lend support to the use of fire for reducing scattered patches of tall woody cover to enhance survival of nests of ≥1 grassland bird species in northern mixed-grass prairies, but further study is needed that incorporates experimental approaches and assessments of shorter term effects of fire on survival of nests of grassland passerines.

  11. Potential Effects of Climate Change on the Distribution of Cold-Tolerant Evergreen Broadleaved Woody Plants in the Korean Peninsula.

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    Kyung Ah Koo

    Full Text Available Climate change has caused shifts in species' ranges and extinctions of high-latitude and altitude species. Most cold-tolerant evergreen broadleaved woody plants (shortened to cold-evergreens below are rare species occurring in a few sites in the alpine and subalpine zones in the Korean Peninsula. The aim of this research is to 1 identify climate factors controlling the range of cold-evergreens in the Korean Peninsula; and 2 predict the climate change effects on the range of cold-evergreens. We used multimodel inference based on combinations of climate variables to develop distribution models of cold-evergreens at a physiognomic-level. Presence/absence data of 12 species at 204 sites and 6 climatic factors, selected from among 23 candidate variables, were used for modeling. Model uncertainty was estimated by mapping a total variance calculated by adding the weighted average of within-model variation to the between-model variation. The range of cold-evergreens and model performance were validated by true skill statistics, the receiver operating characteristic curve and the kappa statistic. Climate change effects on the cold-evergreens were predicted according to the RCP 4.5 and RCP 8.5 scenarios. Multimodel inference approach excellently projected the spatial distribution of cold-evergreens (AUC = 0.95, kappa = 0.62 and TSS = 0.77. Temperature was a dominant factor in model-average estimates, while precipitation was minor. The climatic suitability increased from the southwest, lowland areas, to the northeast, high mountains. The range of cold-evergreens declined under climate change. Mountain-tops in the south and most of the area in the north remained suitable in 2050 and 2070 under the RCP 4.5 projection and 2050 under the RCP 8.5 projection. Only high-elevations in the northeastern Peninsula remained suitable under the RCP 8.5 projection. A northward and upper-elevational range shift indicates change in species composition at the alpine and

  12. Potential Effects of Climate Change on the Distribution of Cold-Tolerant Evergreen Broadleaved Woody Plants in the Korean Peninsula.

    Science.gov (United States)

    Koo, Kyung Ah; Kong, Woo-Seok; Nibbelink, Nathan P; Hopkinson, Charles S; Lee, Joon Ho

    2015-01-01

    Climate change has caused shifts in species' ranges and extinctions of high-latitude and altitude species. Most cold-tolerant evergreen broadleaved woody plants (shortened to cold-evergreens below) are rare species occurring in a few sites in the alpine and subalpine zones in the Korean Peninsula. The aim of this research is to 1) identify climate factors controlling the range of cold-evergreens in the Korean Peninsula; and 2) predict the climate change effects on the range of cold-evergreens. We used multimodel inference based on combinations of climate variables to develop distribution models of cold-evergreens at a physiognomic-level. Presence/absence data of 12 species at 204 sites and 6 climatic factors, selected from among 23 candidate variables, were used for modeling. Model uncertainty was estimated by mapping a total variance calculated by adding the weighted average of within-model variation to the between-model variation. The range of cold-evergreens and model performance were validated by true skill statistics, the receiver operating characteristic curve and the kappa statistic. Climate change effects on the cold-evergreens were predicted according to the RCP 4.5 and RCP 8.5 scenarios. Multimodel inference approach excellently projected the spatial distribution of cold-evergreens (AUC = 0.95, kappa = 0.62 and TSS = 0.77). Temperature was a dominant factor in model-average estimates, while precipitation was minor. The climatic suitability increased from the southwest, lowland areas, to the northeast, high mountains. The range of cold-evergreens declined under climate change. Mountain-tops in the south and most of the area in the north remained suitable in 2050 and 2070 under the RCP 4.5 projection and 2050 under the RCP 8.5 projection. Only high-elevations in the northeastern Peninsula remained suitable under the RCP 8.5 projection. A northward and upper-elevational range shift indicates change in species composition at the alpine and subalpine

  13. Inventorying and pinpoint mapping of woody plants in the European and North American sectors of arboretum of the PetrSU Botanic Garden

    Directory of Open Access Journals (Sweden)

    Eglacheva Arina

    2015-12-01

    Full Text Available Modern information technologies allow us to combine different types of data into a unified system and to determine a transformation of species under the new conditions of introduction (Prokhorov et al., 2013, Annenkovа, 2014. In Karelia, arboretum of the PetrSU Botanic Garden has an exceptional importance due to the species diversity and organization of planting. Regardless of the various long-term studies conducted in the arboretum, no dot distribution map of plants is available today. The article represents mapping results of more than 500 woody plants on the territory of the arboretum’s European and North American sectors. Each object has complete information about its dendrometric characteristics, phytosanitary status, and presence of epiphytic organisms found on it (fungi, lichens, mosses.

  14. Ability of crassulacean acid metabolism plants to overcome interacting stresses in tropical environments.

    Science.gov (United States)

    Lüttge, Ulrich

    2010-01-01

    Single stressors such as scarcity of water and extreme temperatures dominate the struggle for life in severely dry desert ecosystems or cold polar regions and at high elevations. In contrast, stress in the tropics typically arises from a dynamic network of interacting stressors, such as availability of water, CO(2), light and nutrients, temperature and salinity. This requires more plastic spatio-temporal responsiveness and versatility in the acquisition and defence of ecological niches. The mode of photosynthesis of crassulacean acid metabolism (CAM) is described and its flexible expression endows plants with powerful strategies for both acclimation and adaptation. Thus, CAM plants are able to inhabit many diverse habitats in the tropics and are not, as commonly thought, successful predominantly in dry, high-insolation habitats. Typical tropical CAM habitats or ecosystems include exposed lava fields, rock outcrops of inselbergs, salinas, savannas, restingas, high-altitude páramos, dry forests and moist forests. Morphotypical and physiotypical plasticity of CAM phenotypes allow a wide ecophysiological amplitude of niche occupation in the tropics. Physiological and biochemical plasticity appear more responsive by having more readily reversible variations in performance than do morphological adaptations. This makes CAM plants particularly fit for the multi-factor stressor networks of tropical forests. Thus, while the physiognomy of semi-deserts outside the tropics is often determined by tall succulent CAM plants, tropical forests house many more CAM plants in terms of quantity (biomass) and quality (species diversity).

  15. Edaphic, structural and physiological contrasts across Amazon Basin forest–savanna ecotones suggest a role for potassium as a key modulator of tropical woody vegetation structure and function

    Directory of Open Access Journals (Sweden)

    J. Lloyd

    2015-11-01

    C / N ratios than nearby forest plots. These soil differences were also reflected in canopy averaged leaf traits with savanna trees typically having higher leaf mass per unit area but lower mass-based nitrogen (Nm and potassium (Km. Both Nm and Km also increased with declining mean annual precipitation (PA, but most area-based leaf traits such as leaf photosynthetic capacity showed no systematic variation with PA or vegetation type. Despite this invariance, when taken in conjunction with other measures such as mean canopy height, area-based soil exchangeable potassium content, [K]sa , proved to be an excellent predictor of several photosynthetic properties (including 13C isotope discrimination. Moreover, when considered in a multivariate context with PA and soil plant available water storage capacity (θP as covariates, [K]sa also proved to be an excellent predictor of stand-level canopy area, providing drastically improved fits as compared to models considering just PA and/or θP. Neither calcium, nor magnesium, nor soil pH could substitute for potassium when tested as alternative model predictors (ΔAIC > 10. Nor for any model could simple soil texture metrics such as sand or clay content substitute for either [K]sa or θP. Taken in conjunction with recent work in Africa and the forests of the Amazon Basin, this suggests – in combination with some newly conceptualised interacting effects of PA and θP also presented here – a critical role for potassium as a modulator of tropical vegetation structure and function.

  16. Plant species richness and abundance in residential yards across a tropical watershed: implications for urban sustainability

    Directory of Open Access Journals (Sweden)

    Cristina P. Vila-Ruiz

    2014-09-01

    Full Text Available Green spaces within residential areas provide important contributions to the sustainability of urban systems. Therefore, studying the characteristics of these areas has become a research priority in cities worldwide. This project evaluated various aspects of the plant biodiversity of residential yards (i.e., front yards and back yards within the Río Piedras watershed in the San Juan metropolitan area of Puerto Rico. Our work included gathering information on vegetation composition and abundance of woody species (i.e., trees, shrubs, palms, ferns and large herbs (>2 m height, species origin (native vs. introduced, and species uses (ornamental, food, and medicinal plants. A total of 424 yards were surveyed within an area of 187,191 m². We found 383 woody species, with shrubs being the most abundant plant habitat. As expected, residential yards hosted a disproportionate amount of introduced species (69.5%. The most common shrub species were all non-native ornamentals, whereas the most common tree species included food trees as well as ornamental plants and two native species. Front yards hosted more ornamental species per unit area than backyards, while the latter had more food plants. The high amount of introduced species may present a challenge in terms of implementation of plant conservation initiatives if there is no clear definition of urban conservation goals. On the other hand, the high frequency of yards containing food plants may facilitate the development of residential initiatives that could provide future adaptive capacity to food shortages.

  17. An engine for global plant diversity: Highest evolutionary turnover and emigration in the American tropics

    Directory of Open Access Journals (Sweden)

    Alexandre eAntonelli

    2015-04-01

    Full Text Available Understanding the processes that have generated the latitudinal biodiversity gradient and the continental differences in tropical biodiversity remains a major goal of evolutionary biology. Here we estimate the timing and direction of range shifts of extant flowering plants (angiosperms between tropical and non-tropical zones, and into and out of the major tropical regions of the world. We then calculate rates of speciation and extinction taking into account incomplete taxonomic sampling. We use a recently published fossil calibrated phylogeny and apply novel bioinformatic tools to code species into user-defined polygons. We reconstruct biogeographic history using stochastic character mapping to compute relative numbers of range shifts in proportion to the number of available lineages through time. Our results, based on the analysis of c. 22,600 species and c. 20 million geo-referenced occurrence records, show no significant differences between the speciation and extinction of tropical and non-tropical angiosperms. This suggests that at least in plants, the tropical biodiversity gradient primarily derives from other factors than differential rates of diversification. In contrast, the outstanding species richness found today in the American tropics (the Neotropics, as compared to tropical Africa and tropical Asia, is associated with significantly higher speciation and extinction rates. This suggests an exceedingly rapid evolutionary turnover, i.e. Neotropical species being formed and replaced by one another at unparalleled rates. In addition, tropical America stands out from other continents by having ‘pumped out’ more species than it received through most of the last 66 million years. These results imply that the Neotropics have acted as an engine for global plant diversity.

  18. A concise biogas plant construction suitable for Ghana and other tropical countries

    Energy Technology Data Exchange (ETDEWEB)

    Gbagbo, J.K.N.

    1997-04-01

    This report is intended to be used by people in the field of biogas for workshops, technicians, teachers to educate as well as to carry out hands on constructions in Ghana and other tropical countries. Chapter 1, discusses the biogas technology, what a biogas plant is, and how it functions. Chapter 2, describes the entire process. Chapter 3, discusses the necessary conditions for fermentation. Chapter 4, the measuring parameters for monitoring the system. Chapter 5, describes the various types of biogas plants suitable for tropical countries. Chapter 6, describes a planning guide for Ghana and other tropical countries. Chapter 7, discusses digester sizing and finally, Chapter 8, describes a concise biogas plant construction suitable for the rural areas of Ghana and other tropical countries. (au)

  19. Biological effects of plant residues with constrasting chemical compositions on plant and soil under humid tropical conditions

    NARCIS (Netherlands)

    Tian, G.

    1992-01-01

    A study on plant residues with contrasting chemical compositions was conducted under laboratory, growth chamber and humid tropical field conditions to understand the function of the soil fauna in the breakdown of plant residues, the cycling of nutrients, in particular nitrogen, and the

  20. Leaf out times of temperate woody plants are related to phylogeny, deciduousness, growth habit and wood anatomy.

    Science.gov (United States)

    Panchen, Zoe A; Primack, Richard B; Nordt, Birgit; Ellwood, Elizabeth R; Stevens, Albert-Dieter; Renner, Susanne S; Willis, Charles G; Fahey, Robert; Whittemore, Alan; Du, Yanjun; Davis, Charles C

    2014-09-01

    Leaf out phenology affects a wide variety of ecosystem processes and ecological interactions and will take on added significance as leaf out times increasingly shift in response to warming temperatures associated with climate change. There is, however, relatively little information available on the factors affecting species differences in leaf out phenology. An international team of researchers from eight Northern Hemisphere temperate botanical gardens recorded leaf out dates of c. 1600 woody species in 2011 and 2012. Leaf out dates in woody species differed by as much as 3 months at a single site and exhibited strong phylogenetic and anatomical relationships. On average, angiosperms leafed out earlier than gymnosperms, deciduous species earlier than evergreen species, shrubs earlier than trees, diffuse and semi-ring porous species earlier than ring porous species, and species with smaller diameter xylem vessels earlier than species with larger diameter vessels. The order of species leaf out was generally consistent between years and among sites. As species distribution and abundance shift due to climate change, interspecific differences in leaf out phenology may affect ecosystem processes such as carbon, water, and nutrient cycling. Our open access leaf out data provide a critical framework for monitoring and modelling such changes going forward. © 2014 The Authors. New Phytologist © 2014 New Phytologist Trust.

  1. The potential sensitivity of tropical plants to increased ultraviolet-B radiation

    International Nuclear Information System (INIS)

    Ziska, L.H.

    1996-01-01

    Little is known concerning the impact of stratospheric ozone depletion and increasing ultraviolet (UV)-B radiation on the phenology and growth of tropical plants. This is because, ostensibly, tropical plants are already exposed to relatively high levels of UV-B radiation (relative to a temperate environment) and should, therefore, possess a greater degree of tolerance to increased UV-B radiation. In this brief review I hope to show that, potentially, direct and indirect effects on photosynthesis, assimilate partitioning, phenology and biomass could occur in both tropical crops (e.g. cassava, rice) and native species (e.g. Cecropia obtusifolia (Bertol. Fl)., Tetramolopium humile (Gray), Nana sandwicensis L.). However, it should be noted that differences in sensitivity to UV-B radiation can be related to experimental conditions, and care should be taken to ensure that the quantity and quality of background solar radiation remains at near ambient conditions. Nevertheless, by integrating current and past studies on the impact of UV-B radiation on tropical species, I hope to be able to demonstrate that photosynthesis, morphology and growth in tropical plants could be directly affected by UV-B radiation and that UV-B radiation may be a factor in species and community dynamics in natural plant populations in the tropics

  2. Design basis tropical cyclone for nuclear power plants

    International Nuclear Information System (INIS)

    1984-01-01

    The general characteristics of tropical cyclones are discussed in this Safety Guide, with particular emphasis on their pressure and wind structures in the light of available data. General methods are given for the evaluation of the relevant parameters of a Probable Maximum Tropical Cyclone (PMTC), which can be used as the Design Basis Tropical Cyclone (DBTC); these parameters then serve as inputs for the derivation of a design basis surge and a design basis wind. A possible method is also given for the evaluation of the PMTC pressure and wind field based on an approach valid primarily for a particular region. This method depends on the results of a theoretical study on the tropical cyclone structure and makes use of a large amount of data, including aircraft reconnaissance observations for 170 most intense tropical cyclones near the coast of Japan, Taiwan and the Philippines for the period 1960-1974, as well as detailed analyses of all the extreme storms along the Gulf of Mexico and the east coast of the USA during 1900-1978, for the determination of the necessary parameters

  3. Predicting tropical plant physiology from leaf and canopy spectroscopy.

    Science.gov (United States)

    Doughty, Christopher E; Asner, Gregory P; Martin, Roberta E

    2011-02-01

    A broad regional understanding of tropical forest leaf photosynthesis has long been a goal for tropical forest ecologists, but it has remained elusive due to difficult canopy access and high species diversity. Here we develop an empirical model to predict sunlit, light-saturated, tropical leaf photosynthesis using leaf and simulated canopy spectra. To develop this model, we used partial least squares (PLS) analysis on three tropical forest datasets (159 species), two in Hawaii and one at the biosphere 2 laboratory (B2L). For each species, we measured light-saturated photosynthesis (A), light and CO(2) saturated photosynthesis (A(max)), respiration (R), leaf transmittance and reflectance spectra (400-2,500 nm), leaf nitrogen, chlorophyll a and b, carotenoids, and leaf mass per area (LMA). The model best predicted A [r(2) = 0.74, root mean square error (RMSE) = 2.9 μmol m(-2) s(-1))] followed by R (r(2) = 0.48), and A(max) (r(2) = 0.47). We combined leaf reflectance and transmittance with a canopy radiative transfer model to simulate top-of-canopy reflectance and found that canopy spectra are a better predictor of A (RMSE = 2.5 ± 0.07 μmol m(-2) s(-1)) than are leaf spectra. The results indicate the potential for this technique to be used with high-fidelity imaging spectrometers to remotely sense tropical forest canopy photosynthesis.

  4. Tree planting by small producers in the tropics: A comparative study of Brazil and Panama.

    Science.gov (United States)

    Cynthia S. Simmons; Robert T. Walker; Charles H. Wood

    2002-01-01

    Forest regrowth is a notable phenomenon across the tropical forest latitudes. Such reforestation takes place in the wake of land abandonment, occurs cyclically in a rotational agricultural system, and may result from the deliberate planting of trees by farmers. Although less extensive than successional forest regeneration, tree planting by small farmers can have...

  5. A dynamic leaf gas-exchange strategy is conserved in woody plants under changing ambient CO2: evidence from carbon isotope discrimination in paleo and CO2 enrichment studies

    Science.gov (United States)

    Rising atmospheric [CO2], ca, is expected to affect stomatal regulation of leaf gas-exchange of woody plants, thus influencing energy fluxes as well as carbon (C), water and nutrient cycling of forests. Researchers have reported that stomata regulate leaf gas-exchange around “set...

  6. The potential of four woody species for the revegetation of fly ash deposits from the ‘Nikola Tesla-a’ thermoelectric plant (Obrenovac, Serbia

    Directory of Open Access Journals (Sweden)

    Kostić Olga

    2012-01-01

    Full Text Available Four woody species, Tamarix tentandra Pallas, Populus alba L. and Robinia pseudoacacia L. (planted and Amorpha fruticosa L. (naturally colonized were studied at two fly ash deposit lagoons, weathered 3 (L1 and 11 years (L2. All species were assessed in terms of their invasive ability, photosynthetic efficiency, photosynthetic pigments and damage symptoms, while the characteristics of the habitat were assessed in terms of trace element content and the pH and EC of the ash. A reduced vitality of all populations growing on the ash was observed, except for the naturally colonized A. fruticosa. High vitality on all sites, except at L2, increased chlorophyll content and absence of damage symptoms indicates a tolerance in relation to the uptake of toxic elements from the ash. Therefore, the characteristics of naturally colonized species can be used for modeling future actions of biological restoration of fly ash deposits.

  7. The Spatial Pattern and Interactions of Woody Plants on the Temperate Savanna of Inner Mongolia, China: The Effects of Alternating Seasonal Grazing-Mowing Regimes.

    Directory of Open Access Journals (Sweden)

    Xiao Wang

    Full Text Available Ulmus pumila tree-dominated temperate savanna, which is distributed widely throughout the forest-steppe ecotone on the Mongolian Plateau, is a relatively stable woody-herbaceous complex ecosystem in northern China. Relatively more attention has been paid to the degradation of typical steppe areas, whereas less focus has been placed on the succession of this typical temperate savanna under the present management regime. In this study, we established 3 sample plots 100 m×100 m in size along a gradient of fixed distances from one herder's stationary site and then surveyed all the woody plants in these plots. A spatial point pattern analysis was employed to clarify the spatial distribution and interaction of these woody plants. The results indicated that old U. pumila trees (DBH ≥ 20 cm showed a random distribution and that medium U. pumila trees (5 cm ≤ DBH < 20 cm showed an aggregated distribution at a smaller scale and a random distribution at a larger scale; few or no juvenile trees (DBH < 5 cm were present, and seedlings (without DBH formed aggregations in all 3 plots. These findings can be explained by an alternate seasonal grazing-mowing regime (exclosure in summer, mowing in autumn and grazing in winter and spring; the shrubs in all 3 plots exist along a grazing gradient that harbors xerophytic and mesophytic shrubs. Of these shrubs, xerophytic shrubs show significant aggregation at a smaller scale (0-5.5 m, whereas mesophytic shrubs show significant aggregation at a larger scale (0-25 m, which may be the result of the dual effects of grazing pressure and climate change. Medium trees and seedlings significantly facilitate the distributions of xerophytic shrubs and compete significantly with mesophytic shrubs due to differences in water use strategies. We conclude that the implementation of an alternative grazing-mowing regime results in xerophytic shrub encroachment or existence, breaking the chain of normal succession in a U. pumila

  8. Responses of Woody Plant Functional Traits to Nitrogen Addition: A Meta-Analysis of Leaf Economics, Gas Exchange, and Hydraulic Traits.

    Science.gov (United States)

    Zhang, Hongxia; Li, Weibin; Adams, Henry D; Wang, Anzhi; Wu, Jiabing; Jin, Changjie; Guan, Dexin; Yuan, Fenghui

    2018-01-01

    Atmospheric nitrogen (N) deposition has been found to significantly affect plant growth and physiological performance in terrestrial ecosystems. Many individual studies have investigated how N addition influences plant functional traits, however these investigations have usually been limited to a single species, and thereby do not allow derivation of general patterns or underlying mechanisms. We synthesized data from 56 papers and conducted a meta-analysis to assess the general responses of 15 variables related to leaf economics, gas exchange, and hydraulic traits to N addition among 61 woody plant species, primarily from temperate and subtropical regions. Results showed that under N addition, leaf area index (+10.3%), foliar N content (+7.3%), intrinsic water-use efficiency (+3.1%) and net photosynthetic rate (+16.1%) significantly increased, while specific leaf area, stomatal conductance, and transpiration rate did not change. For plant hydraulics, N addition significantly increased vessel diameter (+7.0%), hydraulic conductance in stems/shoots (+6.7%), and water potential corresponding to 50% loss of hydraulic conductivity ( P 50 , +21.5%; i.e., P 50 became less negative), while water potential in leaves (-6.7%) decreased (became more negative). N addition had little effect on vessel density, hydraulic conductance in leaves and roots, or water potential in stems/shoots. N addition had greater effects on gymnosperms than angiosperms and ammonium nitrate fertilization had larger effects than fertilization with urea, and high levels of N addition affected more traits than low levels. Our results demonstrate that N addition has coupled effects on both carbon and water dynamics of woody plants. Increased leaf N, likely fixed in photosynthetic enzymes and pigments leads to higher photosynthesis and water use efficiency, which may increase leaf growth, as reflected in LAI results. These changes appear to have downstream effects on hydraulic function through increases

  9. Effect of Small-Scale Variations in Environmental Factors on the Distribution of Woody Species in Tropical Deciduous Forests of Vindhyan Highlands, India

    Directory of Open Access Journals (Sweden)

    R. K. Chaturvedi

    2011-01-01

    Full Text Available The aim of this study is to investigate the changes in the composition of mature, naturally established and unmanaged TDF in response to small-scale variations in environmental factors. All woody species with a minimum circumference of 10 cm at 1.37 m height were surveyed in forty-five 20×50 m plots distributed over 5 sites in the TDF of Vindhyan highlands, India. Cluster analysis identified two distinct groups of plots. Group 1 plots had higher soil moisture content (SMC, clay, organic C, total N, total P, and light attenuation than group 2 plots. A total of 48 native species belonging to 25 families were encountered in the sampled area. High eigenvalues for the first two Canonical Correspondence Analysis (CCA axes indicated the occurrence of species in distinct groups, and significant correlations of the axes with environmental variables indicated the effect of these variables on species grouping. In conclusion, patchiness in the soil resources needs to be considered in restoration efforts. The results of this study are expected to facilitate the decision regarding choice of species in afforestation programmes for restoring the TDF.

  10. Accumulation and long-term behavior of radiocaesium in tropical plants

    International Nuclear Information System (INIS)

    Carvalho, C.; Mosquera, B.; Anjos, R.M.; Sanches, N.; Bastos, J.; Macario, K.; Veiga, R.

    2006-01-01

    The accumulation and distribution of 40 K and 137 Cs in tropical plant species were studied through measurements of gamma-ray spectra from mango, avocado, guava, pomegranate, chili pepper, papaya and manioc trees. Our goal was to infer their differences in the uptake and translocation of ions to the aboveground plant parts and to establish the suitability of using radiocaesium as a tracer for the plant uptake of nutrients such as K + . (author)

  11. Accumulation and long-term behavior of radiocaesium in tropical plants

    Energy Technology Data Exchange (ETDEWEB)

    Carvalho, C.; Mosquera, B.; Anjos, R.M.; Sanches, N.; Bastos, J.; Macario, K.; Veiga, R. [Universidade Federal Fluminense, Niteroi, RJ (Brazil). Inst. de Fisica

    2006-12-15

    The accumulation and distribution of {sup 40}K and {sup 137}Cs in tropical plant species were studied through measurements of gamma-ray spectra from mango, avocado, guava, pomegranate, chili pepper, papaya and manioc trees. Our goal was to infer their differences in the uptake and translocation of ions to the aboveground plant parts and to establish the suitability of using radiocaesium as a tracer for the plant uptake of nutrients such as K{sup +}. (author)

  12. RAINBIO: a mega-database of tropical African vascular plants distributions

    Directory of Open Access Journals (Sweden)

    Dauby Gilles

    2016-11-01

    Full Text Available The tropical vegetation of Africa is characterized by high levels of species diversity but is undergoing important shifts in response to ongoing climate change and increasing anthropogenic pressures. Although our knowledge of plant species distribution patterns in the African tropics has been improving over the years, it remains limited. Here we present RAINBIO, a unique comprehensive mega-database of georeferenced records for vascular plants in continental tropical Africa. The geographic focus of the database is the region south of the Sahel and north of Southern Africa, and the majority of data originate from tropical forest regions. RAINBIO is a compilation of 13 datasets either publicly available or personal ones. Numerous in depth data quality checks, automatic and manual via several African flora experts, were undertaken for georeferencing, standardization of taxonomic names and identification and merging of duplicated records. The resulting RAINBIO data allows exploration and extraction of distribution data for 25,356 native tropical African vascular plant species, which represents ca. 89% of all known plant species in the area of interest. Habit information is also provided for 91% of these species.

  13. Woody biomass policies and location decisions of the woody bioenergy industry in the southern United States

    International Nuclear Information System (INIS)

    Guo, Zhimei; Hodges, Donald G.; Young, Timothy M.

    2013-01-01

    Woody biomass for bioenergy production has been included in relatively few renewable energy policies since the 1970s. Recently, however, several states have implemented a variety of new woody biomass policies to spur the establishment of new bioenergy industry. Establishing new woody biomass-based facilities in a specific state is affected by a number of factors such as the strength of these new policy incentives, resource availability, business tax climate, and the available labor force. This study employs a conditional logit model (CLM) to explore the effects of woody biomass policies on the siting decisions of new bioenergy projects relative to some of these other state attributes. The CLM results suggest that state government incentives are significantly related to state success in attracting new plants. The results have substantial implications regarding woody biomass policies and the creation of a new bioenergy industry. -- Highlights: •This study explores the effects of state attributes on the siting decisions of new woody bioenergy projects. •Results suggest that state woody biomass policies are significantly related to state success in attracting new plants. •Other factors related to the siting of woody bioenergy facilities include resource availability, taxes, and wage rate

  14. The sentinel tree nursery as an early warning system for pathway risk assessment: Fungal pathogens associated with Chinese woody plants commonly shipped to Europe.

    Directory of Open Access Journals (Sweden)

    Anna Maria Vettraino

    Full Text Available Introduction of and invasion by alien plant pathogens represents the main cause of emerging infectious diseases affecting domesticated and wild plant species worldwide. The trade in living plants is the most common pathway of introduction. Many of the alien tree pathogens recently introduced into Europe were not previously included on any quarantine lists. To help determine the potential risk of pest introduction through trading of ornamental plants, a sentinel nursery was established in Beijing, China in 2008. The sentinel nursery planting included four of the most common ornamental woody species shipped to Europe including Ilex cornuta var. fortunae, Zelkova schneideriana, Fraxinus chinensis and Buxus microphylla. Symptoms developing on these species within the sentinel nursery were detected in 2013 and consisted of necrotic spots on leaves, canker and stem necrosis, shoot blight and shoot necrosis. Fungi associated with the trees and their symptoms included Alternaria alternata detected from all hosts; Diaporthe liquidambaris and Diaporthe capsici from bark and leaf necrosis of Zelkova schneideriana; Botryosphaeria dothidea and Nothophoma quercina from stem cankers on Fraxinus chinensis and leaf necrosis on Ilex cornuta; and Pseudonectria foliicola from leaf necrosis on Buxus microphylla. Next generation sequencing analysis from asymptomatic tissues detected eighteen OTU's at species level among which some taxa had not been previously recorded in Europe. These results clearly demonstrate that looking at trees of internationally traded species in the region of origin can reveal the presence of potentially harmful organisms of major forestry, landscape or crop trees. Results of this study also provide an indication as to how some disease agents can be introduced using pathways other than the co-generic hosts. Hence, sentinel nurseries represent one potential mechanism to address the current lack of knowledge about pests in the countries from

  15. Mutualism, hybrid inviability and speciation in a tropical ant-plant.

    Science.gov (United States)

    Léotard, G; Saltmarsh, A; Kjellberg, F; McKey, D

    2008-07-01

    Although biotic interactions are particularly intricate in the tropics, few studies have examined whether divergent adaptations to biotic interactions lead to speciation in tropical organisms. Ant-plant mutualisms are widespread in the tropics. Within Leonardoxa africana, two subspecies present contrasting defences against herbivores. Young leaves of subsp. africana are defended by mutualistic ants, whereas subsp. gracilicaulis satiates herbivores by synchronized leaf production. Subsp. africana possesses hollow internodes and many large foliar nectaries, housing and feeding ants. We detected no genetic introgression between the two subspecies in the contact zone between them. F1 hybrids were present. They were intermediate in phenotype, expressing reduced, nonfunctional but costly myrmecophilic traits. However, they suffered more herbivory than their parents. Hybrids remained small, failing to reach reproductive size, probably due to their maladapted defence phenotype. Hence, there could be a direct link between adaptation to mutualism and reproductive isolation: biotic interactions could be a driver of tropical diversity.

  16. Plant litter dynamics in the forest-stream interface: precipitation is a major control across tropical biomes

    OpenAIRE

    Tonin, Alan M.; Gon?alves, Jos? F.; Bambi, Paulino; Couceiro, Sheyla R. M.; Feitoza, Lorrane A. M.; Fontana, Lucas E.; Hamada, Neusa; Hepp, Luiz U.; Lezan-Kowalczuk, V?nia G.; Leite, Gustavo F. M.; Lemes-Silva, Aurea L.; Lisboa, Leonardo K.; Loureiro, Rafael C.; Martins, Renato T.; Medeiros, Adriana O.

    2017-01-01

    Riparian plant litter is a major energy source for forested streams across the world and its decomposition has repercussions on nutrient cycling, food webs and ecosystem functioning. However, we know little about plant litter dynamics in tropical streams, even?though the tropics occupy 40% of the Earth?s land surface. Here we investigated spatial and temporal (along a year cycle) patterns of litter inputs and storage in multiple streams of three tropical biomes in Brazil (Atlantic forest, Ama...

  17. PHYTOSOCIOLOGY AND STRUCTURAL CHARACTERIZATION OF WOODY REGENERATION FROM A REFORESTATION WITH NATIVE SPECIES IN SOUTHEASTERN BRAZIL

    Directory of Open Access Journals (Sweden)

    Michel Anderson Almeida Colmanetti

    2016-04-01

    Full Text Available ABSTRACT In Brazil, specifically in São Paulo State, there are guidelines based on the high diversity of tropical forests that instructs the restoration projects in the state (current SMA 32/2014. The main goal of this study was verify the importance and effectiveness of the high diversity of arboreal species originated from a reforestation, and its influence in a woody regenerating composition. We developed a phytosociologic study in a woody regenerating stratum of a nine year old reforestation at a Private Reserve of Natural Heritage (RPPN, in Mogi-Guaçu, São Paulo State. All specimens with height > 30 cm and Diameter at Breast Height (DBH < 5 cm were evaluated. The woody regenerating diversity was smaller than the overstory diversity and the species composition was similar to the overstory. The Simpson index (1-D was 0.85, Shannon index (H' was 2.46 and the Pielou index (J' was 0.60. The zoochoric dispersion syndrome was major among the species. Our results suggest that the use of high diversity of native seedlings in a reforestation leads to high diversity of species in woody regeneration stratum, after one decade of planting.

  18. PEMANFAATAN DAUN TANAMAN BERKAYU SEBAGAI PUPUK ORGANIK TANAMAN SAYURAN DAN JAGUNG - (UTILIZATION OF WOODY PLANT LEAVES AS ORGANIC FERTILIZER FOR VEGETABLES AND CORN

    Directory of Open Access Journals (Sweden)

    Dody Priadi

    2017-12-01

    Full Text Available This study aimed to use woody plant leaves as organic fertilizer (compost and their effects on vegetables and corn. The compost was made from leaves of Samanea saman, Swietenia macrophylla, Nephelium lappaceum and cow dung (1:3, 2:2 and 3:1 using OrgaDec (0.5% w/w, Decomic (0.1% v/w and Dectro (0.1 v/w as bioactivator. The result showed that compost from Samanea saman leaves and cow dung (1:3 using Decomic (0.1% v/w met the organic fertilizer standard. The compost was applied to Ipomoea reptans, Capsicum annuum and Zea mays on a media from compost and latosol soil (1:3, 2:2 and 3:1 using Completely Randomized Design (CRD with 3 replications. The analyzed data using ANOVA showed no significant difference in the growth parameter of tested plants. The best media for Ipomoea reptans was the mixture of compost and latosol soil (3:1 meanwhile for Zea mays and Capsicum annuum were 1:3 and 2:2, respectively.Keywords: compost, compost application, organic fertilizer, woody plant leavesABSTRAKPenelitian ini bertujuan untuk memanfaatkan daun tumbuhan berkayu menjadi pupuk organik (kompos serta pengaruhnya terhadap tanaman sayuran dan jagung. Kompos dibuat dari daun kihujan (Samanea saman, daun mahoni (Swietenia macrophylla daun rambutan (Nephelium lappaceum dan kotoran sapi (1:3, 2:2 dan 3:1 dengan penambahan bioaktivator OrgaDec (0,5% w/w, Decomic (0,1% v/w dan Dectro (0,1 v/w. Hasil analisis kimia menunjukkan bahwa kompos yang dibuat dari daun kihujan dan kotoran sapi (1:3 yang menggunakan bioaktivator Decomic (0,1% v/w adalah perlakuan yang paling sesuai dengan baku mutu pupuk organik berdasarkan Permentan No.70/Permentan/SR.140/10/2011. Kompos hasil penelitian diujicobakan kepada tanaman kangkung darat (Ipomoea reptans, cabe keriting (Capsicum annuum dan jagung manis (Zea mays pada media campuran kompos dan tanah latosol (1:3, 2:2 dan 3:1 menggunakan Rancangan Acak Lengkap (RAL dengan 3 ulangan sedangkan data yang diperoleh diolah dengan ANOVA

  19. [Effects of Different Modifier Concentrations on Lead-Zinc Tolerance, Subcellular Distribution and Chemical Forms for Four Kinds of Woody Plants].

    Science.gov (United States)

    Chen, Yong-hua; Zhang, Fu-yun; Wu, Xiao-fu; Liang, Xi; Yuan, Si-wen

    2015-10-01

    Four kinds of lead-zinc tolerant woody plants: Nerium oleander, Koelreuteria paniculata, Paulownia and Boehmeria were used as materials to estimate their enrichment and transferable capacity of lead (Pb) and zinc (Zn) and analyze the subcellular distribution and chemical speciation of Zn and Ph in different parts of plants, under different modifier concentrations (CK group: 100% lead-zinc slag plus a small amount of phosphate fertilizer, improved one: 85% of lead-zinc slag ± 10% peat ± 5% bacterial manure plus a small amount of phosphate fertilizer, improved two: 75% lead-zinc slag ± 20% peat ± 5% bacterial manure ± a small amount of phosphate). Results showed that: (1) The content of Pb, Zn in matrix after planting four kinds of plants was lower than before, no significant difference between improved one and improved two of Nerium oleander and Boehmeria was found, but improved two was better than improved one of Paulownia, while improved one was better than improved two of Koelreuteria paniculata; Four plants had relatively low aboveground enrichment coefficient of Pb and Zn, but had a high transfer coefficient, showed that the appropriate modifier concentration was able to improve the Pb and Zn enrichment and transfer ability of plants. (2) In subcellular distribution, most of Pb and Zn were distributed in plant cell wall components and soluble components while the distribution in cell organelles such as mitochondria, chloroplasts and nucleus component were less. Compared with CK group, two improved group made soluble components of the cell walls of Pb fixation and retention of zinc role in the enhancement. (3) As for the chemical forms of Pb and Zn in plants, the main chemical forms of Pb were hydrochloric acid, sodium chloride and ethanol extractable forms, while other chemical form contents were few, the main chemical forms of Zn were different based on plant type. Compared with CK group, the proportion of the active Pb chemical form in different plant

  20. Synopsis: the role of prescribed burning in regenerating Quercus macrocarpa and associated woody plants in stringer woodlands in the Black Hills, South Dakota

    Science.gov (United States)

    Carolyn Hull Sieg; Henry A. Wright

    1998-01-01

    Poor tree reproduction, sparse shrub cover, and increasing amounts of exotic species such as Kentucky bluegrass (Poa pratensis) are common problems in woody draws in the Northern Great Plains. Although the historic role of fire in maintaining woody draws is unclear, it is likely that these woodlands burned periodically, especially in dry years on hot...

  1. Global atmospheric change and herbivory: Effects of elevated levels of UV-B radiation, atmospheric CO2 and temperature on boreal woody plants and their herbivores

    International Nuclear Information System (INIS)

    Veteli, T.

    2003-01-01

    The aim of this study was to assess the effects of elevated ultraviolet-B radiation (UV-B, 280- 320 nm), atmospheric CO 2 , temperature and soil nitrogen level on the growth and chemical quality of boreal deciduous woody plants and on performance of the herbivorous insects feeding on them. Eggs and larvae of Operophtera brumata (L.) (Lepidoptera, Geometridae) were subjected to elevated UV-B radiation in the laboratory. Two willow species, Salix phylicifolia L. (Salicaceae) and S. myrsinifolia Salisb., were grown in an UV-B irradiation field where the responses of both plants and their herbivorous insects were monitored. S. myrsinifolia, Betula pendula Ehrh. (Betulaceae) and B. pubescens Roth. were subjected to elevated CO 2 and temperature and different fertilisation levels in closed-top climatic chambers. To assess the indirect effects of the different treatments, the leaves of experimental willows and birches were fed to larvae of Phratora vitellinae (L.) (Coleoptera, Chrysomelidae) and adults of Agellastica alni L. in the laboratory. Elevated UV-B radiation significantly decreased the survival and performance of eggs and larvae of O. brumata. It also increased concentrations of some flavonoids and phenolic acids in S. myrsinifolia and S. phylicifolia, while the low-UV-B- absorbing phenolics, e. g. condensed tannins, gallic acid derivatives and salicylates, either decreased or remained unaffected. Both the height growth and biomass of one S. phylicifolia clone was sensitive to elevated levels of UV-B radiation. Abundance of adults and larvae of a willow- feeding leaf beetle, P. vitellinae, was increased under elevated UV-B; but this did not lead to increased leaf damage on the host plants. There were no significant differences in performance of the larvae feeding on differentially treated willow leaves, but adult A. alni preferred UV-B-treated leaves to ambient control leaves. Elevated CO 2 and temperature significantly increased the height growth of S

  2. Has frugivory influenced the macroecology and diversification of a tropical keystone plant family?

    Directory of Open Access Journals (Sweden)

    W. Daniel Kissling

    2017-07-01

    Full Text Available Seed dispersal by fruit-eating animals is a pivotal ecosystem function in tropical forests, but the role that frugivores have played in the biogeography and macroevolution of species-rich tropical plant families remains largely unexplored. This project investigates how frugivory-relevant plant traits (e.g. fruit size, fruit color, fruit shape etc. are distributed within the angiosperm family of palms (Arecaceae, how this relates to diversification rates, and whether and how it coincides with the global biogeographic distribution of vertebrate frugivores (birds, bats, primates, other frugivorous mammals and their ecological traits (e.g. diet specialization, body size, flight ability, color vision etc.. Palms are particularly suitable because they are well studied, species-rich, characteristic of tropical rainforests, and dispersed by all groups of vertebrate seed dispersers. Using newly compiled data on species distributions and ecological traits in combination with phylogenies we will test (1 how fruit trait variability relates to palm phylogeny and other aspects of plant morphology (e.g. leaf size, plant height, growth form, (2 whether geographic variability in fruit traits correlates with geographic distributions of animal consumers and their traits, and (3 to what extent interaction-relevant plant traits are related to palm diversification rates. This combined macroecological and macroevolutionary approach allows novel insights into the global ecology and the evolution of a tropical keystone plant family. This is important for the conservation and sustainable management of tropical rainforests because palms are often key components of subsistence economies, ecosystem dynamics and carbon storage and therefore help to enhance nature’s goods, benefits and services to humanity.

  3. Evolution of associations between Cymothoe butterflies and their Rinorea host plants in tropical Africa

    NARCIS (Netherlands)

    Velzen, van R.

    2013-01-01

    This thesis aimed to elucidate the evolutionary history of the associations between Cymothoeforest butterflies (Nymphalidae, Limenitidinae) and their Rinoreahost plants (Violaceae) in tropical Africa. Insects are by far the most diverse group of multicellular organisms on

  4. Potential for biotic resistance from herbivores to tropical and subtropical plant invasions in aquatic ecosystems

    NARCIS (Netherlands)

    Petruzella, A.; Grutters, B.M.C.; Thomaz, S.M.; Bakker, E.S.

    2017-01-01

    Invasions of tropical and subtropical aquatic plants threaten biodiversity and cause ecological and economic impacts worldwide. An urgent question is whether native herbivores are able to inhibit the spread of these alien species thus providing biotic resistance. The potential for biotic resistance

  5. Studies on saponin production in tropical medicinal plants Maesa argentea and Maesa lanceolata

    Science.gov (United States)

    Faizal, Ahmad; Geelen, Danny

    2015-09-01

    The continuous need for new compounds with important medicinal activities has lead to the identification and characterization of various plant-derived natural products. As a part of this program, we studied the saponin production from two tropical medicinal plants Maesa argentea and M. lanceolata and evaluated several treatments to enhance their saponin production. In this experiment, we present the analyses of saponin production from greenhouse grown plants by means of TLC and HPLC-MS. We observed that the content of saponin from these plants varied depending on organ and physiological age of the plants. In addition, the impact of elicitors on saponin accumulation on in vitro grown plants was analyzed using TLC. The production of saponin was very stable and not affected by treatment with methyl jasmonate, and salicylic acid. In conclusion, Maesa saponins are constitutively produced in plants and the level of these compounds in plants is mainly affected by the developmental or physiological stage.

  6. Correlation between earthworms and plant litter decomposition in a tropical wet forest of Puerto Rico.

    Science.gov (United States)

    Jennifer Dechainea; Honghua Ruanb; Yaniria Sanchez-de Leon; Xiaoming Zou

    2005-01-01

    Earthworms are recognized to play an important role in the decomposition of organic materials. To test the use of earthworms as an indicator of plant litter decomposition, we examined the abundance and biomass of earthworms in relation to plant litter decomposition in a tropical wet forest of Puerto Rico. We collected earthworms at 0–0.1m and 0.1–0.25m soil depths from...

  7. Plant-pollinator interactions in tropical monsoon forests in Southeast Asia.

    Science.gov (United States)

    Kato, Makoto; Kosaka, Yasuyuki; Kawakita, Atsushi; Okuyama, Yudai; Kobayashi, Chisato; Phimminith, Thavy; Thongphan, Daovorn

    2008-11-01

    Forests with different flora and vegetation types harbor different assemblages of flower visitors, and plant-pollinator interactions vary among forests. In monsoon-dominated East and Southeast Asia, there is a characteristic gradient in climate along latitude, creating a broad spectrum of forest types with potentially diverse pollinator communities. To detect a geographical pattern of plant-pollinator interactions, we investigated flowering phenology and pollinator assemblages in the least-studied forest type, i.e., tropical monsoon forest, in the Vientiane plain in Laos. Throughout the 5-year study, we observed 171 plant species blooming and detected flower visitors on 145 species. Flowering occurred throughout the year, although the number of flowering plant species peaked at the end of dry season. The dominant canopy trees, including Dipterocarpaceae, bloomed annually, in contrast to the supra-annual general flowering that occurs in Southeast Asian tropical rain forests. Among the 134 native plant species, 68 were pollinated by hymenopterans and others by lepidopterans, beetles, flies, or diverse insects. Among the observed bees, Xylocopa, megachilids, and honeybees mainly contributed to the pollination of canopy trees, whereas long-tongued Amegilla bees pollinated diverse perennials with long corolla tubes. This is the first community-level study of plant-pollinator interactions in an Asian tropical monsoon forest ecosystem.

  8. Assessment Of Local Tropical Plants For Phytoremediation Of ...

    African Journals Online (AJOL)

    Panicum maximum) and Water Leaf (Talinum triangulare) local plants under normal environmental conditions in remediating soil contaminated with a Nigerian crude oil sample. Composite soil sample obtained by mixing equal weight in ...

  9. Three cycles of water deficit from seed to young plants of Moringa oleifera woody species improves stress tolerance.

    Science.gov (United States)

    Rivas, Rebeca; Oliveira, Marciel T; Santos, Mauro G

    2013-02-01

    The main objective of this study was to assess whether recurring water stress occurring from seed germination to young plants of Moringa oleifera Lam. are able to mitigate the drought stress effects. Germination, gas exchange and biochemical parameters were analysed after three cycles of water deficit. Young plants were used 50 days after germination under three osmotic potentials (0.0, -0.3 and -0.4 MPa). For each germination treatment, control (irrigated) and stressed (10% of water control) plants were compared for a total of six treatments. There were two cycles of drought interspersed with 10 days of rehydration. The young plants of M. oleifera showed increased tolerance to repeated cycles of drought, maintaining high relative water content (RWC), high water use efficiency (WUE), increased photosynthetic pigments and increased activity of antioxidant enzymes. There was rapid recovery of the photosynthetic rate during the rehydration period. The stressed plants from the -0.3 and -0.4 MPa treatments showed higher tolerance compared to the control plants. The results suggest that seeds of M. oleifera subjected to mild water deficit have had increased the ability for drought tolerance when young plant. Copyright © 2012 Elsevier Masson SAS. All rights reserved.

  10. Alien plant invasions in tropical and sub-tropical savannas: patterns, processes and prospects

    Czech Academy of Sciences Publication Activity Database

    Foxcroft, L. C.; Richardson, D. M.; Rejmánek, M.; Pyšek, Petr

    2010-01-01

    Roč. 12, č. 12 (2010), s. 3913-3933 ISSN 1387-3547 R&D Projects: GA MŠk LC06073 Institutional research plan: CEZ:AV0Z60050516 Keywords : savannas * plant invasions * world Subject RIV: EF - Botanics Impact factor: 3.474, year: 2010

  11. Cooling performance assessment of horizontal earth tube system and effect on planting in tropical greenhouse

    International Nuclear Information System (INIS)

    Mongkon, S.; Thepa, S.; Namprakai, P.; Pratinthong, N.

    2014-01-01

    Graphical abstract: - Highlights: • The cooling ability of HETS is studied for planting in tropical greenhouse. • The effective of system was moderate with COP more than 2.0. • Increasing diameter and air velocity increase COP more than other parameters. • The plant growth with HETS was significantly better than no-HETS plant. - Abstract: The benefit of geothermal energy is used by the horizontal earth tube system (HETS); which is not prevalent in tropical climate. This study evaluated geothermal cooling ability and parameters studied in Thailand by mathematical model. The measurement of the effect on plant cultivation was carried out in two identical greenhouses with 30 m 2 of greenhouse volume. The HETS supplied cooled air to the model greenhouse (MGH), and the plant growth results were compared to the growth results of a conventional greenhouse (CGH). The prediction demonstrated that the coefficient of performance (COP) in clear sky day would be more than 2.0 while in the experiment it was found to be moderately lower. The parameters study could be useful for implementation of a system for maximum performance. Two plants Dahlias and head lettuce were grown satisfactory. The qualities of the plants with the HETS were better than the non-cooled plants. In addition, the quality of production was affected by variations of microclimate in the greenhouses and solar intensity throughout the cultivation period

  12. Role of biotechnology in medicinal plants | Tripathi | Tropical Journal ...

    African Journals Online (AJOL)

    Bioreactors are the key step towards commercial production of secondary metabolites by plant biotechnology. Genetic transformation may be a powerful tool for enhancing the productivity of novel secondary metabolites; especially by Agrobacterium rhizogenes induced hairy roots. This article discusses the applications of ...

  13. Tropical community tree guide: benefits, costs, and strategic planting

    Science.gov (United States)

    Kelaine E. Vargas; Gregory E. McPherson; James R. Simpson; Paula J. Peper; Shelley L. Gardner; Qingfu Xiao

    2008-01-01

    Even as they increase the beauty of our surroundings, trees provide us with a great many ecosystem services, including air quality improvement, energy conservation, stormwater interception, and atmospheric carbon dioxide reduction. These benefits must be weighed against the costs of maintaining trees, including planting, pruning, irrigation, administration, pest...

  14. Biomethanol production from gasification of non-woody plant in South Africa: Optimum scale and economic performance

    Energy Technology Data Exchange (ETDEWEB)

    Amigun, Bamikole, E-mail: bamigun@csir.co.z [Sustainable Energy Futures, Natural Resources and the Environment, Council for Scientific and Industrial Research (CSIR), Pretoria (South Africa); Process Engineering Department, Stellenbosch University, Private Bag X1, Matieland, Stellenbosch 7602 (South Africa); Gorgens, Johann; Knoetze, Hansie [Process Engineering Department, Stellenbosch University, Private Bag X1, Matieland, Stellenbosch 7602 (South Africa)

    2010-01-15

    Methanol production from biomass is a promising carbon neutral fuel, well suited for use in fuel cell vehicles (FCVs), as transportation fuel and as chemical building block. The concept used in this study incorporates an innovative Absorption Enhanced Reforming (AER) gasification process, which enables an efficient conversion of biomass into a hydrogen-rich gas (syngas) and then, uses the Mitsubishi methanol converter (superconverter) for methanol synthesis. Technical and economic prospects for production of methanol have been evaluated. The methanol plants described have a biomass input between 10 and 2000 MW{sub th}. The economy of the methanol production plants is very dependent on the production capacity and large-scale facilities are required to benefit from economies of scale. However, large-scale plants are likely to have higher transportation costs per unit biomass transported as a result of longer transportation distances. Analyses show that lower unit investment costs accompanying increased production scale outweighs the cost for transporting larger quantities of biomass. The unit cost of methanol production mostly depends on the capital investments. The total unit cost of methanol is found to decrease from about 10.66 R/l for a 10 MW{sub th} to about 6.44 R/l for a 60 MW{sub th} and 3.95 R/l for a 400 MW{sub th} methanol plant. The unit costs stabilise (a near flat profile was observed) for plant sizes between 400 and 2000 MW{sub th}, but the unit cost do however continue to decrease to about 2.89 R/l for a 2000 MW{sub th} plant. Long term cost reduction mainly resides in technological learning and large-scale production. Therefore, technology development towards large-scale technology that takes into account sustainable biomass production could be a better choice due to economic reasons.

  15. Biomethanol production from gasification of non-woody plant in South Africa. Optimum scale and economic performance

    Energy Technology Data Exchange (ETDEWEB)

    Amigun, Bamikole [Sustainable Energy Futures, Natural Resources and the Environment, Council for Scientific and Industrial Research (CSIR), Pretoria (South Africa); Process Engineering Department, Stellenbosch University, Private Bag X1, Matieland, Stellenbosch 7602 (South Africa); Gorgens, Johann; Knoetze, Hansie [Process Engineering Department, Stellenbosch University, Private Bag X1, Matieland, Stellenbosch 7602 (South Africa)

    2010-01-15

    Methanol production from biomass is a promising carbon neutral fuel, well suited for use in fuel cell vehicles (FCVs), as transportation fuel and as chemical building block. The concept used in this study incorporates an innovative Absorption Enhanced Reforming (AER) gasification process, which enables an efficient conversion of biomass into a hydrogen-rich gas (syngas) and then, uses the Mitsubishi methanol converter (superconverter) for methanol synthesis. Technical and economic prospects for production of methanol have been evaluated. The methanol plants described have a biomass input between 10 and 2000 MW{sub th}. The economy of the methanol production plants is very dependent on the production capacity and large-scale facilities are required to benefit from economies of scale. However, large-scale plants are likely to have higher transportation costs per unit biomass transported as a result of longer transportation distances. Analyses show that lower unit investment costs accompanying increased production scale outweighs the cost for transporting larger quantities of biomass. The unit cost of methanol production mostly depends on the capital investments. The total unit cost of methanol is found to decrease from about 10.66 R/l for a 10 MW{sub th} to about 6.44 R/l for a 60 MW{sub th} and 3.95 R/l for a 400 MW{sub th} methanol plant. The unit costs stabilise (a near flat profile was observed) for plant sizes between 400 and 2000 MW{sub th}, but the unit cost do however continue to decrease to about 2.89 R/l for a 2000 MW{sub th} plant. Long term cost reduction mainly resides in technological learning and large-scale production. Therefore, technology development towards large-scale technology that takes into account sustainable biomass production could be a better choice due to economic reasons. (author)

  16. Biomethanol production from gasification of non-woody plant in South Africa: Optimum scale and economic performance

    International Nuclear Information System (INIS)

    Amigun, Bamikole; Gorgens, Johann; Knoetze, Hansie

    2010-01-01

    Methanol production from biomass is a promising carbon neutral fuel, well suited for use in fuel cell vehicles (FCVs), as transportation fuel and as chemical building block. The concept used in this study incorporates an innovative Absorption Enhanced Reforming (AER) gasification process, which enables an efficient conversion of biomass into a hydrogen-rich gas (syngas) and then, uses the Mitsubishi methanol converter (superconverter) for methanol synthesis. Technical and economic prospects for production of methanol have been evaluated. The methanol plants described have a biomass input between 10 and 2000 MW th . The economy of the methanol production plants is very dependent on the production capacity and large-scale facilities are required to benefit from economies of scale. However, large-scale plants are likely to have higher transportation costs per unit biomass transported as a result of longer transportation distances. Analyses show that lower unit investment costs accompanying increased production scale outweighs the cost for transporting larger quantities of biomass. The unit cost of methanol production mostly depends on the capital investments. The total unit cost of methanol is found to decrease from about 10.66 R/l for a 10 MW th to about 6.44 R/l for a 60 MW th and 3.95 R/l for a 400 MW th methanol plant. The unit costs stabilise (a near flat profile was observed) for plant sizes between 400 and 2000 MW th , but the unit cost do however continue to decrease to about 2.89 R/l for a 2000 MW th plant. Long term cost reduction mainly resides in technological learning and large-scale production. Therefore, technology development towards large-scale technology that takes into account sustainable biomass production could be a better choice due to economic reasons.

  17. The contrasting nature of woody plant species in different neotropical forest biomes reflects differences in ecological stability.

    Science.gov (United States)

    Pennington, R Toby; Lavin, Matt

    2016-04-01

    A fundamental premise of this review is that distinctive phylogenetic and biogeographic patterns in clades endemic to different major biomes illuminate the evolutionary process. In seasonally dry tropical forests (SDTFs), phylogenies are geographically structured and multiple individuals representing single species coalesce. This pattern of monophyletic species, coupled with their old species stem ages, is indicative of maintenance of small effective population sizes over evolutionary timescales, which suggests that SDTF is difficult to immigrate into because of persistent resident lineages adapted to a stable, seasonally dry ecology. By contrast, lack of coalescence in conspecific accessions of abundant and often widespread species is more frequent in rain forests and is likely to reflect large effective population sizes maintained over huge areas by effective seed and pollen flow. Species nonmonophyly, young species stem ages and lack of geographical structure in rain forest phylogenies may reflect more widespread disturbance by drought and landscape evolution causing resident mortality that opens up greater opportunities for immigration and speciation. We recommend full species sampling and inclusion of multiple accessions representing individual species in phylogenies to highlight nonmonophyletic species, which we predict will be frequent in rain forest and savanna, and which represent excellent case studies of incipient speciation. © 2015 The Authors. New Phytologist © 2015 New Phytologist Trust.

  18. Trait assembly of woody plants in communities across sub-alpine gradients: Identifying the role of limiting similarity

    NARCIS (Netherlands)

    Yan, B.; Zhang, J.; Liu, Y.; Li, Z.; Huang, X.; Yang, W.; Prinzing, A.

    2012-01-01

    Questions - Plant species can be assembled into communities through habitat filtering or species competition, but their relative roles are still debated. We do not know whether there is limited similarity between co-existing species when accounting for the parallel effect of abiotic habitat

  19. Application of digital field photographs as documents for tropical plant inventory1

    Science.gov (United States)

    LaFrankie, James V.; Chua, Anna I.

    2015-01-01

    Premise of the study: We tested the credibility and significance of digital field photographs as supplements or substitutes for conventional herbarium specimens with particular relevance to exploration of the tropics. Methods: We made 113 collections in triplicate at a species-rich mountain in the Philippines while we took 1238 digital photographs of the same plants. We then identified the plants from the photographs alone, categorized the confidence of the identification and the reason for failure to identify, and compared the results to identifications based on the dried specimens. Results: We identified 72.6% of the photographic sets with high confidence and 27.4% with low confidence or only to genus. In no case was a confident identification altered by subsequent examination of the dried specimen. The failure to identify photographic sets to species was due to the lack of a key feature in 67.8% of the cases and due to a poorly understood taxonomy in 32.2%. Discussion: We conclude that digital photographs cannot replace traditional herbarium specimens as the primary elements that document tropical plant diversity. However, photographs represent a new and important artifact that aids an expedient survey of tropical plant diversity while encouraging broad public participation. PMID:25995976

  20. Application of digital field photographs as documents for tropical plant inventory.

    Science.gov (United States)

    LaFrankie, James V; Chua, Anna I

    2015-05-01

    We tested the credibility and significance of digital field photographs as supplements or substitutes for conventional herbarium specimens with particular relevance to exploration of the tropics. We made 113 collections in triplicate at a species-rich mountain in the Philippines while we took 1238 digital photographs of the same plants. We then identified the plants from the photographs alone, categorized the confidence of the identification and the reason for failure to identify, and compared the results to identifications based on the dried specimens. We identified 72.6% of the photographic sets with high confidence and 27.4% with low confidence or only to genus. In no case was a confident identification altered by subsequent examination of the dried specimen. The failure to identify photographic sets to species was due to the lack of a key feature in 67.8% of the cases and due to a poorly understood taxonomy in 32.2%. We conclude that digital photographs cannot replace traditional herbarium specimens as the primary elements that document tropical plant diversity. However, photographs represent a new and important artifact that aids an expedient survey of tropical plant diversity while encouraging broad public participation.

  1. Minimizing Risks of Invasive Alien Plant Species in Tropical Production Forest Management

    Directory of Open Access Journals (Sweden)

    Michael Padmanaba

    2014-08-01

    Full Text Available Timber production is the most pervasive human impact on tropical forests, but studies of logging impacts have largely focused on timber species and vertebrates. This review focuses on the risk from invasive alien plant species, which has been frequently neglected in production forest management in the tropics. Our literature search resulted in 114 publications with relevant information, including books, book chapters, reports and papers. Examples of both invasions by aliens into tropical production forests and plantation forests as sources of invasions are presented. We discuss species traits and processes affecting spread and invasion, and silvicultural practices that favor invasions. We also highlight potential impacts of invasive plant species and discuss options for managing them in production forests. We suggest that future forestry practices need to reduce the risks of plant invasions by conducting surveillance for invasive species; minimizing canopy opening during harvesting; encouraging rapid canopy closure in plantations; minimizing the width of access roads; and ensuring that vehicles and other equipment are not transporting seeds of invasive species. Potential invasive species should not be planted within dispersal range of production forests. In invasive species management, forewarned is forearmed.

  2. How to help woody plants to overcome drought stress?-a control study of four tree species in Northwest China.

    Science.gov (United States)

    Liu, Xiaozhen; Zhang, Shuoxin

    2010-05-01

    Water is essential for plants and involves most physical and chemical processes within their lifecycles. Drought stress is a crucial limiting factor for plant growth and production. 48% of the land in China is arid and semi-arid, and non-irrigated land occupies approximately 51.9% of the total cultivated areas. Therefore, studies on plant drought resistant mechanisms have great significance for improving water use efficiency and thus increasing productivity of economical plants. Prior research has shown that the application of nitrogenous fertilizer affects the drought-resistant characteristics of plants. This study aimed to reveal the effect of nitrogenous fertilizer on physiological aspects and its impact on the drought resistance of four tree species (Robinia pseudoacacia L., Ligustrum lucidum Ait., Acer truncatum Bge. and Ulmus pumila L. ) in northwest China. Three levels of nitrogen fertilization (46% N based of urea adjusted to: 5g/15g soil, 15g/15g soil and 25g/15g soil) and an additional control study were applied to 2-year-old well-grown seedlings under drought conditions (30% field moisture capacity). Stomatal conductance, transpiration rate and net photosynthetic rate were measured by a LI-6400 photosynthesis system, while water use efficiency was calculated from net photosynthesis rate and transpiration rate. The results revealed that as the amount of urea applied was raised, stomatal conductance, transpiration rate and net photosynthetic rate decreased significantly, and thus water use efficiency significantly increased. It is therefore concluded that the application of nitrogenous fertilizer regulated physiological parameters by reducing stomata conductance to improve water use efficiency. In addition, among the four tree species, U. pumila had the maximum value of water use efficiency under the same drought condition. The outcome of this study provides a guided option for forest management in arid and semi-arid areas of northwest China.

  3. Distribution of invasive and native riparian woody plants across the western USA in relation to climate, river flow, floodplain geometry and patterns of introduction

    Science.gov (United States)

    Ryan McShane,; Daniel Auerbach,; Friedman, Jonathan M.; Auble, Gregor T.; Shafroth, Patrick B.; Michael Merigliano,; Scott, Michael L.; N. Leroy Poff,

    2015-01-01

    Management of riparian plant invasions across the landscape requires understanding the combined influence of climate, hydrology, geologic constraints and patterns of introduction. We measured abundance of nine riparian woody taxa at 456 stream gages across the western USA. We constructed conditional inference recursive binary partitioning models to discriminate the influence of eleven environmental variables on plant occurrence and abundance, focusing on the two most abundant non-native taxa, Tamarix spp. and Elaeagnus angustifolia, and their native competitor Populus deltoides. River reaches in this study were distributed along a composite gradient from cooler, wetter higher-elevation reaches with higher stream power and earlier snowmelt flood peaks to warmer, drier lower-elevation reaches with lower power and later peaks. Plant distributions were strongly related to climate, hydrologic and geomorphic factors, and introduction history. The strongest associations were with temperature and then precipitation. Among hydrologic and geomorphic variables, stream power, peak flow timing and 10-yr flood magnitude had stronger associations than did peak flow predictability, low-flow magnitude, mean annual flow and channel confinement. Nearby intentional planting of Elaeagnus was the best predictor of its occurrence, but planting of Tamarix was rare. Higher temperatures were associated with greater abundance of Tamarix relative to P. deltoides, and greater abundance of P. deltoides relative toElaeagnus. Populus deltoides abundance was more strongly related to peak flow timing than was that of Elaeagnus or Tamarix. Higher stream power and larger 10-yr floods were associated with greater abundance of P. deltoides and Tamarix relative to Elaeagnus. Therefore, increases in temperature could increase abundance of Tamarix and decrease that of Elaeagnus relative to P. deltoides, changes in peak flow timing caused by climate change or dam operations could

  4. Phytomedicinal potential of tropical cloudforest plants from Monteverde, Costa Rica

    Directory of Open Access Journals (Sweden)

    Mary C Setzer

    2003-09-01

    Full Text Available A pharmacological survey of plants from Monteverde, Costa Rica, including 165 species representing 61 families has been carried out. Crude plant extracts have been tested for in-vitro bactericidal and fungicidal activity as well as cytotoxic and anti-herpes activity. Of these, 123 extracts exhibited notable cytotoxicity, 62 showed antibacterial activity, 4 showed antifungal activity, and 8 showed promising antiviral activity. Thus, 101 of the plant species examined in this work, or 62%, showed marked bioactivity in one or more bioassays. These results underscore the phytomedicinal potential of Neotropical cloud forestsSe realizó un análisis farmacológico de plantas de Monteverde, Costa Rica, que incluye 165 especies representantes de 61 familias. Se probó in-vitro la actividad bactericida y fungicida, así como la actividad citotóxica y anti-herpes de extractos crudos de plantas. De estos, 123 extractos exhibieron una notable citotoxicidad, 62 mostraron actividad antibacterial, 4 presentaron actividad antihongos, y 8 mostraron una promisoria actividad antiviral. Así, de las 101 especies de plantas examinadas en este trabajo, 62% presentaron una marcada actividad biológica en uno o más de los bioensayos. Estos resultados subrayan el potencial fitomédico de los bosques nubosos Neotropicales

  5. Characterization of the serine acetyltransferase gene family of Vitis vinifera uncovers differences in regulation of OAS synthesis in woody plants

    OpenAIRE

    Silvia eTavares; Silvia eTavares; Markus eWirtz; Marcel Pascal Beier; Jochen eBogs; Jochen eBogs; Jochen eBogs; Ruediger eHell; Sara eAmâncio

    2015-01-01

    In higher plants cysteine biosynthesis is catalyzed by O-acetylserine(thiol)lyase (OASTL) and represents the last step of the assimilatory sulfate reduction pathway. It is mainly regulated by provision of O-acetylserine (OAS), the nitrogen/carbon containing backbone for fixation of reduced sulfur. OAS is synthesized by Serine acetyltransferase (SERAT), which reversibly interacts with OASTL in the cysteine synthase complex (CSC). In this study we identify and characterize the SERAT protein fam...

  6. Characterization of the serine acetyltransferase gene family of Vitis vinifera uncovers differences in regulation of OAS synthesis in woody plants

    OpenAIRE

    Tavares, Sílvia; Wirtz, Markus; Beier, Marcel P.; Bogs, Jochen; Hell, Rüdiger; Amâncio, Sara

    2015-01-01

    In higher plants cysteine biosynthesis is catalyzed by O-acetylserine(thiol)lyase (OASTL) and represents the last step of the assimilatory sulfate reduction pathway. It is mainly regulated by provision of O-acetylserine (OAS), the nitrogen/carbon containing backbone for fixation of reduced sulfur. OAS is synthesized by Serine acetyltransferase (SERAT), which reversibly interacts with OASTL in the cysteine synthase complex (CSC). In this study we identify and characterize the SERAT gene family...

  7. The use of short and long PCR products for improved detection of prunus necrotic ringspot virus in woody plants.

    Science.gov (United States)

    Rosner, A; Maslenin, L; Spiegel, S

    1997-09-01

    The reverse transcriptase-polymerase chain reaction (RT-PCR) was used for detection of prunus necrotic ringspot virus (PNRSV) in dormant peach and almond trees by the application of two different pairs of primers yielding a short and a long product, respectively. The relative amount of the short (200 base pair, bp) product was higher than the longer (785 bp) product. PNRSV was detected better in plant tissues with a low virus concentration (e.g. dormant trees) by amplification of the short PCR product, whereas the long product was product was produced at higher virus titers. Simultaneous amplification of both short and long products was demonstrated using a three-primer mixture in a single reaction tube. In this assay, amplification of either PCR product indicated the presence of PNRSV-specific sequences in the plant tissue examined, thus covering a wide range of virus concentrations in a single test. Dilution of the RNA extracted from infected plant material resulted in a steep decline in the amplification of both short and long PCR products. In contrast, serial dilutions of the intermediate cDNA template differentially affected the amplification patterns: the relative amount of the short product increased whereas that of the long product decreased. These results may explain the preferential amplification of the short PCR product observed in samples containing low virus concentrations.

  8. Genomics approaches to unlock the high yield potential of cassava, a tropical model plant

    Directory of Open Access Journals (Sweden)

    Shengkui ZHANG,Ping'an MA,Haiyan WANG,Cheng LU,Xin CHEN,Zhiqiang XIA,Meiling ZOU,Xinchen ZHOU,Wenquan WANG

    2014-12-01

    Full Text Available Cassava, a tropical food, feed and biofuel crop, has great capacity for biomass accumulation and an extraordinary efficiency in water use and mineral nutrition, which makes it highly suitable as a model plant for tropical crops. However, the understanding of the metabolism and genomics of this important crop is limited. The recent breakthroughs in the genomics of cassava, including whole-genome sequencing and transcriptome analysis, as well as advances in the biology of photosynthesis, starch biosynthesis, adaptation to drought and high temperature, and resistance to virus and bacterial diseases, are reviewed here. Many of the new developments have come from comparative analyses between a wild ancestor and existing cultivars. Finally, the current challenges and future potential of cassava as a model plant are discussed.

  9. Woody Allen kimpus arhitektuuriga

    Index Scriptorium Estoniae

    2000-01-01

    Woody Allen protesteerib oma uue lühifilmiga kavatsuse vastu ehitada 16-korruseline ärihoone tema New Yorgi kodu lähedale. W. Allen hindab New Yorgi ajaloolisi rajoone, mida näitab ka oma filmides

  10. Pinus tropical com potencial para uso em plantios comerciais no Brasil. Tropical pine for commercial planting in Brazil.

    Directory of Open Access Journals (Sweden)

    Marcos Silveira WREGE

    2014-06-01

    Full Text Available Entre os pinus tropicais, Pinus caribaea var. hondurensis é uma variedade natural, oriunda de região com clima tropical na América Central. A espécie se aclimatou bem em várias partes do mundo, em regiões com alta pluviosidade e temperaturas elevadas. Embora não tolere geadas severas, pode ser plantada em partes da região Sul do Brasil onde o clima é mais quente e a frequência de geadas é menor e é indicado para plantio em boa parte do Brasil, em mais de 3,5 milhões de km2 . Essa é uma variedade que apresenta alto rendimento em madeira de boa qualidade, além de possibilitar a exploração da resina. Neste trabalho, são apresentadas as regiões no Brasil que apresentam potencial para cultivo dessa variedade em regime de silvicultura intensiva, tomando como base sua região de origem no mundo. São indicadas para plantio comercial as zonas com os menores riscos de geada nos estados da região Sul, no Estado de São Paulo e nas demais regiões que oferecem condições climáticas favoráveis, principalmente de disponibilidade hídrica para o desenvolvimento dessa variedade de pinus. – Among tropical pines, Pinus caribaea var. hondurensis is a natural variation from the tropical regions of Central America. The species has adapted well in various parts of the world, in regions with high rainfall and high temperatures. Although intolerance to severe frosts, it can be grown in parts of southern Brazil, where the climate is hot, with infrequent frosts and even can be used for commercial planting in over 3.5 million square kilometers.This variety presents high yield in quality wood as well as resin. This work shows regions in Brazil where environmental conditions are favorable for commercial plantations with this variety, by making comparisons with the conditions in its origin. Climatic zones within the Southern Region, as well as in the state of São Paulo and elsewhere with the lowest risks of frost and plenty of water for the

  11. An exceptional role for flowering plant physiology in the expansion of tropical rainforests and biodiversity.

    Science.gov (United States)

    Boyce, C Kevin; Lee, Jung-Eun

    2010-11-22

    Movement of water from soil to atmosphere by plant transpiration can feed precipitation, but is limited by the hydraulic capacities of plants, which have not been uniform through time. The flowering plants that dominate modern vegetation possess transpiration capacities that are dramatically higher than any other plants, living or extinct. Transpiration operates at the level of the leaf, however, and how the impact of this physiological revolution scales up to the landscape and larger environment remains unclear. Here, climate modelling demonstrates that angiosperms help ensure aseasonally high levels of precipitation in the modern tropics. Most strikingly, replacement of angiosperm with non-angiosperm vegetation would result in a hotter, drier and more seasonal Amazon basin, decreasing the overall area of ever-wet rainforest by 80 per cent. Thus, flowering plant ecological dominance has strongly altered climate and the global hydrological cycle. Because tropical biodiversity is closely tied to precipitation and rainforest area, angiosperm climate modification may have promoted diversification of the angiosperms themselves, as well as radiations of diverse vertebrate and invertebrate animal lineages and of epiphytic plants. Their exceptional potential for environmental modification may have contributed to divergent responses to similar climates and global perturbations, like mass extinctions, before and after angiosperm evolution.

  12. Decreased losses of woody plant foliage to insects in large urban areas are explained by bird predation.

    Science.gov (United States)

    Kozlov, Mikhail V; Lanta, Vojtěch; Zverev, Vitali; Rainio, Kalle; Kunavin, Mikhail A; Zvereva, Elena L

    2017-10-01

    Despite the increasing rate of urbanization, the consequences of this process on biotic interactions remain insufficiently studied. Our aims were to identify the general pattern of urbanization impact on background insect herbivory, to explore variations in this impact related to characteristics of both urban areas and insect-plant systems, and to uncover the factors governing urbanization impacts on insect herbivory. We compared the foliar damage inflicted on the most common trees by defoliating, leafmining and gall-forming insects in rural and urban habitats associated with 16 European cities. In two of these cities, we explored quality of birch foliage for herbivorous insects, mortality of leafmining insects due to predators and parasitoids and bird predation on artificial plasticine larvae. On average, the foliage losses to insects were 16.5% lower in urban than in rural habitats. The magnitude of the overall adverse effect of urbanization on herbivory was independent of the latitude of the locality and was similar in all 11 studied tree species, but increased with an increase in the size of the urban area: it was significant in large cities (city population 1-5 million) but not significant in medium-sized and small towns. Quality of birch foliage for herbivorous insects was slightly higher in urban habitats than in rural habitats. At the same time, leafminer mortality due to ants and birds and the bird attack intensity on dummy larvae were higher in large cities than in rural habitats, which at least partially explained the decline in insect herbivory observed in response to urbanization. Our findings underscore the importance of top-down forces in mediating impacts of urbanization on plant-feeding insects: factors favouring predators may override the positive effects of temperature elevation on insects and thus reduce plant damage. © 2017 John Wiley & Sons Ltd.

  13. Characterization of the serine acetyltransferase gene family of Vitis vinifera uncovers differences in regulation of OAS synthesis in woody plants

    Science.gov (United States)

    Tavares, Sílvia; Wirtz, Markus; Beier, Marcel P.; Bogs, Jochen; Hell, Rüdiger; Amâncio, Sara

    2015-01-01

    In higher plants cysteine biosynthesis is catalyzed by O-acetylserine(thiol)lyase (OASTL) and represents the last step of the assimilatory sulfate reduction pathway. It is mainly regulated by provision of O-acetylserine (OAS), the nitrogen/carbon containing backbone for fixation of reduced sulfur. OAS is synthesized by Serine acetyltransferase (SERAT), which reversibly interacts with OASTL in the cysteine synthase complex (CSC). In this study we identify and characterize the SERAT gene family of the crop plant Vitis vinifera. The identified four members of the VvSERAT protein family are assigned to three distinct groups upon their sequence similarities to Arabidopsis SERATs. Expression of fluorescently labeled VvSERAT proteins uncover that the sub-cellular localization of VvSERAT1;1 and VvSERAT3;1 is the cytosol and that VvSERAT2;1 and VvSERAT2;2 localize in addition in plastids and mitochondria, respectively. The purified VvSERATs of group 1 and 2 have higher enzymatic activity than VvSERAT3;1, which display a characteristic C-terminal extension also present in AtSERAT3;1. VvSERAT1;1 and VvSERAT2;2 are evidenced to form the CSC. CSC formation activates VvSERAT2;2, by releasing CSC-associated VvSERAT2;2 from cysteine inhibition. Thus, subcellular distribution of SERAT isoforms and CSC formation in cytosol and mitochondria is conserved between Arabidopsis and grapevine. Surprisingly, VvSERAT2;1 lack the canonical C-terminal tail of plant SERATs, does not form the CSC and is almost insensitive to cysteine inhibition (IC50 = 1.9 mM cysteine). Upon sulfate depletion VvSERAT2;1 is strongly induced at the transcriptional level, while transcription of other VvSERATs is almost unaffected in sulfate deprived grapevine cell suspension cultures. Application of abiotic stresses to soil grown grapevine plants revealed isoform-specific induction of VvSERAT2;1 in leaves upon drought, whereas high light- or temperature- stress hardly trigger VvSERAT2;1 transcription. PMID:25741355

  14. Gas exchange and plant growth after defoliation on Leandra lacunosa, a cerrado woody species with continuous leaf production

    Directory of Open Access Journals (Sweden)

    Maria Angélica Damascos

    2005-11-01

    Full Text Available Morphological and physiological leaf traits were studied on control and defoliated potted Leandra lacunosa young plants. After defoliation, remaining bottom leaves showed no significant change in net photosynthesis and stomatal conductance values with time, but the leaf transpiration rate was higher. The production of the new leaves was greater after defoliation in top defoliated plants. Bottom defoliated plants increased stem extension rates and net photosynthesis transitorily. Two months after defoliation, control and defoliated plants did not differ in stem length and root dry mass values. In spite of smaller area and photosynthetic capacity, remaining bottom leaves were able to compensate top leaves elimination. The effectiveness of this compensatory response, however, depended on the ability of new leaves to escape from herbivores.Características morfológicas e fisiológicas foliares foram estudadas em indivíduos jovens envasados de Leandra lacunosa que sofreram desfolhamento e em indivíduos controle. Após o desfolhamento, as folhas remanescentes da parte inferior não apresentaram mudanças significativas dos valores de fotossíntese e condutância estomática. Entretanto, a taxa de transpiração foliar foi maior quando comparada com plantas desfolhadas em porções inferiores. A rebrota de folhas foi maior após o desfolhamento da parte superior. Nas plantas desfolhadas em porções inferiores, ocorreu, momentaneamente, aumento da taxa fotossintética e da extensão do caule. Após dois meses de desfolhamento as plantas controle e desfolhadas não diferiram quanto aos valores do comprimento do caule e massa seca da raiz. Portanto, apesar da menor área foliar e menor capacidade fotossintética, as folhas na parte inferior foram capazes de compensar a eliminação das folhas superiores. A efetividade desta resposta compensatória, no entanto, dependerá da habilidade das novas folhas emitidas escaparem do ataque dos herbívoros.

  15. A dynamic leaf gas-exchange strategy is conserved in woody plants under changing ambient CO2: evidence from carbon isotope discrimination in paleo and CO2 enrichment studies

    Science.gov (United States)

    Voelker, Steven L.; Brooks, J. Renée; Meinzer, Frederick C.; Anderson, Rebecca D.; Bader, Martin K.-F.; Battipaglia, Giovanna; Becklin, Katie M.; Beerling, David; Bert, Didier; Betancourt, Julio L.; Dawson, Todd E.; Domec, Jean-Christophe; Guyette, Richard P.; Körner, Christian; Leavitt, Steven W.; Linder, Sune; Marshall, John D.; Mildner, Manuel; Ogée, Jérôme; Panyushkina, Irina P.; Plumpton, Heather J.; Pregitzer, Kurt S.; Saurer, Matthias; Smith, Andrew R.; Siegwolf, Rolf T.W.; Stambaugh, Michael C.; Talhelm, Alan F.; Tardif, Jacques C.; Van De Water, Peter K.; Ward, Joy K.; Wingate, Lisa

    2016-01-01

    Rising atmospheric [CO2], ca, is expected to affect stomatal regulation of leaf gas-exchange of woody plants, thus influencing energy fluxes as well as carbon (C), water, and nutrient cycling of forests. Researchers have proposed various strategies for stomatal regulation of leaf gas-exchange that include maintaining a constant leaf internal [CO2], ci, a constant drawdown in CO2(ca − ci), and a constant ci/ca. These strategies can result in drastically different consequences for leaf gas-exchange. The accuracy of Earth systems models depends in part on assumptions about generalizable patterns in leaf gas-exchange responses to varying ca. The concept of optimal stomatal behavior, exemplified by woody plants shifting along a continuum of these strategies, provides a unifying framework for understanding leaf gas-exchange responses to ca. To assess leaf gas-exchange regulation strategies, we analyzed patterns in ci inferred from studies reporting C stable isotope ratios (δ13C) or photosynthetic discrimination (∆) in woody angiosperms and gymnosperms that grew across a range of ca spanning at least 100 ppm. Our results suggest that much of the ca-induced changes in ci/ca occurred across ca spanning 200 to 400 ppm. These patterns imply that ca − ci will eventually approach a constant level at high ca because assimilation rates will reach a maximum and stomatal conductance of each species should be constrained to some minimum level. These analyses are not consistent with canalization toward any single strategy, particularly maintaining a constant ci. Rather, the results are consistent with the existence of a broadly conserved pattern of stomatal optimization in woody angiosperms and gymnosperms. This results in trees being profligate water users at low ca, when additional water loss is small for each unit of C gain, and increasingly water-conservative at high ca, when photosystems are saturated and water loss is large for each unit C gain.

  16. L’escalfament global i l’extinció de les plantes: un exemple tropical

    OpenAIRE

    Safont, Elisabet; Rull, Valentí; Vegas-Vilarrúbia, Teresa; Nogué, Sandra

    2011-01-01

    [EN]Global warminG and plant extinction: a tropical example. – Pantepui is a phytogeographical province made up of a group of approximately 50 tabular mountain summits or tepuis in southeast Venezuela. This region lies between 1500 and 3014 m a.s.l and covers an approximate area of 6000 km2. Its pristine state of conservation is remarkable. The summits of the tepuis contain an excep- tional level of vascular plant diversity, including 2446 known species, of which 771 are endemic t...

  17. Constraints on water transport posed by xylem embolism: implications for drought and frost resistance in woody plants

    OpenAIRE

    Martínez Vilalta, Jordi

    2001-01-01

    Consultable des del TDX Títol obtingut de la portada digitalitzada Introducció L'aigua és un recurs i un factor limitant per la vida de les plantes. El transport d'aigua des de les arrels fins a les fulles té lloc fonamentalment a través del xilema. La capacitat d'aquest teixit per transportar aigua (i.e., la seva conductivitat hidràulica) no és constant sinó que depèn de les condicions en què es produeix el transport. En particular, quan els potencials hídrics es fan molt negatius (seq...

  18. The opportunity cost of not utilising the woody invasive alien plant species in the Kouga, Krom and Baviaans catchments in South Africa

    Directory of Open Access Journals (Sweden)

    Thulile Vundla

    2016-12-01

    Full Text Available This study estimates the opportunity costs of using woody invasive alien plants (IAPs for value-added products by estimating the net economic return from the value-added industries in South Africa. By 2008, IAPs were estimated at the national level to cover an area of 1 813 million condensed hectares in South Africa. A market has formed around their use for value-added products (VAP like charcoal, firewood and timber in the Kouga, Kromme and Baviaans River catchments in the Eastern Cape province of South Africa. The net economic return from these value-added industries was estimated for the purpose of several management scenarios, and was then used to estimate the opportunity costs if they were not used. A system dynamics model was used to value and analyse the Net Present Value of clearing in the study area and to estimate the opportunity cost of the non-use of VAP. The study showed that the inclusion of VAPs in the project would yield higher net present values for clearing. The findings from this study suggest that a cofinance option of the total economic returns from VAP for clearing costs is the best management scenario for reducing the costs of clearing and maximising the net economic returns from clearing. The net economic returns of VAPs by 2030 are estimated at R23 million without the co-finance option and R26 million with the option. The cumulative net income from VAPs with co-financing over the period of valuation is estimated to be R609 million.

  19. Woody medicinal plants of the caatinga in the state of Pernambuco (Northeast Brazil Plantas medicinais arbóreas da caatinga no Estado de Pernambuco (Nordeste do Brasil

    Directory of Open Access Journals (Sweden)

    Ana Carolina Oliveira da Silva

    2005-03-01

    Full Text Available Floristic and phytosociological studies undertaken in six areas of the state of Pernambuco were selected with the aim of analyzing the Relative Importance of the woody medicinal plant species of Pernambuco's caatinga from an ethnobotanical perspective. For the data analysis, only those identified up to the species level were selected and information on medicinal properties was obtained for each one from the literature. The Relative Importance was calculated for each species. From the 57 woody species, 22 had therapeutic indications; from these, Anacardium occidentale L., Tabebuia impetiginosa (Mart. ex DC Standley, Schinopsis brasiliensis Engl., and Myracrodruon urundeuva (Engl. Fr. All. had the greatest values of Relative Importance. The correlation analysis made clear that the Relative Importance of the species is negatively correlated with the Density and Relative Frequency (pCom o objetivo de analisar, a partir de uma perspectiva etnobotânica, a importância relativa das espécies arbóreas medicinais da caatinga pernambucana, foram selecionados trabalhos florísticos e fitossociológicos realizados em seis áreas no Estado de Pernambuco. Para análise dos dados, foram selecionadas apenas as espécies identificadas até o nível de espécie e para cada uma levantou-se informações medicinais disponíveis na literatura. Para cada espécie calculou-se a importância relativa. Das 57 espécies arbóreas, 22 possuem indicação terapêutica, sendo Anacardium occidentale L., Tabebuia impetiginosa (Mart. ex DC Standley, Schinopsis brasiliensis Engl. e Myracrodruon urundeuva (Engl. Fr. All., as espécies com os maiores valores de Importância Relativa. A análise de correlação evidenciou que a importância relativa das espécies encontra-se negativamente correlacionada com a Densidade e Freqüência Relativas (p< 0,05. As espécies mais importantes, do ponto de vista etnobotânico, são também as mais vulneráveis devido à exploração sistem

  20. Power plant fuel switching and air quality in a tropical, forested environment

    Science.gov (United States)

    Medeiros, Adan S. S.; Calderaro, Gisele; Guimarães, Patricia C.; Magalhaes, Mateus R.; Morais, Marcos V. B.; Rafee, Sameh A. A.; Ribeiro, Igor O.; Andreoli, Rita V.; Martins, Jorge A.; Martins, Leila D.; Martin, Scot T.; Souza, Rodrigo A. F.

    2017-07-01

    How a changing energy matrix for electricity production affects air quality is considered for an urban region in a tropical, forested environment. Manaus, the largest city in the central Amazon Basin of Brazil, is in the process of changing its energy matrix for electricity production from fuel oil and diesel to natural gas over an approximately 10-year period, with a minor contribution by hydropower. Three scenarios of urban air quality, specifically afternoon ozone concentrations, were simulated using the Weather Research and Forecasting (WRF-Chem) model. The first scenario used fuel oil and diesel for electricity production, which was the reality in 2008. The second scenario was based on the fuel mix from 2014, the most current year for which data were available. The third scenario considered nearly complete use of natural gas for electricity production, which is the anticipated future, possibly for 2018. For each case, inventories of anthropogenic emissions were based on electricity generation, refinery operations, and transportation. Transportation and refinery operations were held constant across the three scenarios to focus on effects of power plant fuel switching in a tropical context. The simulated NOx and CO emissions for the urban region decrease by 89 and 55 %, respectively, after the complete change in the energy matrix. The results of the simulations indicate that a change to natural gas significantly decreases maximum afternoon ozone concentrations over the population center, reducing ozone by > 70 % for the most polluted days. The sensitivity of ozone concentrations to the fuel switchover is consistent with a NOx-limited regime, as expected for a tropical forest having high emissions of biogenic volatile organic compounds, high water vapor concentrations, and abundant solar radiation. There are key differences in a shifting energy matrix in a tropical, forested environment compared to other world environments. Policies favoring the burning of

  1. Insecticide dissipation from soil and plant surfaces in tropical horticulture of southern Benin, West Africa.

    Science.gov (United States)

    Rosendahl, Ingrid; Laabs, Volker; Atcha-Ahowé, Cyrien; James, Braima; Amelung, Wulf

    2009-06-01

    In Sub-Saharan Africa, horticulture provides livelihood opportunities for millions of people, especially in urban and peri-urban areas. Although the vegetable agroecosystems are often characterized by intensive pesticide use, risks resulting therefrom are largely unknown under tropical horticultural conditions. The objective of this study therefore was to study the fate of pesticides in two representative horticultural soils (Acrisol and Arenosol) and plants (Solanum macrocarpon L.) after field application and thus to gain first insight on environmental persistence and dispersion of typical insecticides used in vegetable horticulture in Benin, West Africa. On plant surfaces, dissipation was rapid with half lives ranging from 2 to 87 h (alpha-endosulfan < beta-endosulfan < deltamethrin). Soil dissipation was considerably slower than dissipation from plant surfaces with half-lives ranging from 3 (diazinon) to 74 d (total endosulfan), but persistence of pesticides in soil was still reduced compared to temperate climates. Nevertheless, for deltamethrin and endosulfan, a tendency for mid-term accumulation in soil upon repeated applications was observed. The soil and plant surface concentrations of the metabolite endosulfan sulfate increased during the entire trial period, indicating that this compound is a potential long-term pollutant even in tropical environments.

  2. Growing and marketing woody species to support pollinators: An emerging opportunity for forest, conservation, and native plant nurseries in the Northeastern United States

    Science.gov (United States)

    Kas Dumroese; Tara Luna

    2016-01-01

    The decline of insects that pollinate flowers is garnering more attention by land managers, policymakers, and the general public. Nursery managers who grow native trees, shrubs, and woody vines have a promising opportunity to showcase these species, marketing their contributions to pollinator health and other ecosystem services in urban and wild landscapes....

  3. Layout Guide for Burnt and Un-burnt Tropical Forest: The Diversity of Forest Plants and Insetcs for Sustainable Environmental

    Science.gov (United States)

    Watiniasih, N. L.; Tambunan, J.; Merdana, I. M.; Antara, I. N. G.

    2018-04-01

    Forest fire is a common phenomenon in tropical forest likes in Indonesia. Beside the effect of soaring heat and lack of rain during dry season due to the tropical climate, farming system is also reported as one reason of forest fire in Indonesia. People of surrounding areas and neighbouring countries are suffering from the effect of forest fire. Plants and animals are the most suffer from this occurrence that they cannot escape. This study aimed to investigate the effect of previously burnt and un-burnt tropical forest in Borneo Island on the plant and insect diversity of the tropical forest. The result of the study found that the plants in previously burnt forest area was dominated by one species, while higher and more stable plant diversity was found in un-burnt forest. Although the number of individual insects was higher in previously burnt tropical forest, but the insects was more diverse in un-burnt tropical forest. The alteration of environmental conditions in previously burnt and un-burnt forest indicate that the energy held in natural forest support higher number and more stable insects than previously burnt forest.

  4. Patterns in woody vegetation structure across African savannas

    Science.gov (United States)

    Axelsson, Christoffer R.; Hanan, Niall P.

    2017-07-01

    Vegetation structure in water-limited systems is to a large degree controlled by ecohydrological processes, including mean annual precipitation (MAP) modulated by the characteristics of precipitation and geomorphology that collectively determine how rainfall is distributed vertically into soils or horizontally in the landscape. We anticipate that woody canopy cover, crown density, crown size, and the level of spatial aggregation among woody plants in the landscape will vary across environmental gradients. A high level of woody plant aggregation is most distinct in periodic vegetation patterns (PVPs), which emerge as a result of ecohydrological processes such as runoff generation and increased infiltration close to plants. Similar, albeit weaker, forces may influence the spatial distribution of woody plants elsewhere in savannas. Exploring these trends can extend our knowledge of how semi-arid vegetation structure is constrained by rainfall regime, soil type, topography, and disturbance processes such as fire. Using high-spatial-resolution imagery, a flexible classification framework, and a crown delineation method, we extracted woody vegetation properties from 876 sites spread over African savannas. At each site, we estimated woody cover, mean crown size, crown density, and the degree of aggregation among woody plants. This enabled us to elucidate the effects of rainfall regimes (MAP and seasonality), soil texture, slope, and fire frequency on woody vegetation properties. We found that previously documented increases in woody cover with rainfall is more consistently a result of increasing crown size than increasing density of woody plants. Along a gradient of mean annual precipitation from the driest (< 200 mm yr-1) to the wettest (1200-1400 mm yr-1) end, mean estimates of crown size, crown density, and woody cover increased by 233, 73, and 491 % respectively. We also found a unimodal relationship between mean crown size and sand content suggesting that maximal

  5. Patterns in woody vegetation structure across African savannas

    Directory of Open Access Journals (Sweden)

    C. R. Axelsson

    2017-07-01

    Full Text Available Vegetation structure in water-limited systems is to a large degree controlled by ecohydrological processes, including mean annual precipitation (MAP modulated by the characteristics of precipitation and geomorphology that collectively determine how rainfall is distributed vertically into soils or horizontally in the landscape. We anticipate that woody canopy cover, crown density, crown size, and the level of spatial aggregation among woody plants in the landscape will vary across environmental gradients. A high level of woody plant aggregation is most distinct in periodic vegetation patterns (PVPs, which emerge as a result of ecohydrological processes such as runoff generation and increased infiltration close to plants. Similar, albeit weaker, forces may influence the spatial distribution of woody plants elsewhere in savannas. Exploring these trends can extend our knowledge of how semi-arid vegetation structure is constrained by rainfall regime, soil type, topography, and disturbance processes such as fire. Using high-spatial-resolution imagery, a flexible classification framework, and a crown delineation method, we extracted woody vegetation properties from 876 sites spread over African savannas. At each site, we estimated woody cover, mean crown size, crown density, and the degree of aggregation among woody plants. This enabled us to elucidate the effects of rainfall regimes (MAP and seasonality, soil texture, slope, and fire frequency on woody vegetation properties. We found that previously documented increases in woody cover with rainfall is more consistently a result of increasing crown size than increasing density of woody plants. Along a gradient of mean annual precipitation from the driest (< 200 mm yr−1 to the wettest (1200–1400 mm yr−1 end, mean estimates of crown size, crown density, and woody cover increased by 233, 73, and 491 % respectively. We also found a unimodal relationship between mean crown size and sand

  6. Contribution of seagrass plants to CO2 capture in a tropical seagrass meadow under experimental disturbance.

    Science.gov (United States)

    Deyanova, Diana; Gullström, Martin; Lyimo, Liberatus D; Dahl, Martin; Hamisi, Mariam I; Mtolera, Matern S P; Björk, Mats

    2017-01-01

    Coastal vegetative habitats are known to be highly productive environments with a high ability to capture and store carbon. During disturbance this important function could be compromised as plant photosynthetic capacity, biomass, and/or growth are reduced. To evaluate effects of disturbance on CO2 capture in plants we performed a five-month manipulative experiment in a tropical seagrass (Thalassia hemprichii) meadow exposed to two intensity levels of shading and simulated grazing. We assessed CO2 capture potential (as net CO2 fixation) using areal productivity calculated from continuous measurements of diel photosynthetic rates, and estimates of plant morphology, biomass and productivity/respiration (P/R) ratios (from the literature). To better understand the plant capacity to coping with level of disturbance we also measured plant growth and resource allocation. We observed substantial reductions in seagrass areal productivity, biomass, and leaf area that together resulted in a negative daily carbon balance in the two shading treatments as well as in the high-intensity simulated grazing treatment. Additionally, based on the concentrations of soluble carbohydrates and starch in the rhizomes, we found that the main reserve sources for plant growth were reduced in all treatments except for the low-intensity simulated grazing treatment. If permanent, these combined adverse effects will reduce the plants' resilience and capacity to recover after disturbance. This might in turn have long-lasting and devastating effects on important ecosystem functions, including the carbon sequestration capacity of the seagrass system.

  7. Bird Pollinator Visitation is Equivalent in Island and Plantation Planting Designs in Tropical Forest Restoration Sites

    Directory of Open Access Journals (Sweden)

    Ginger M. Thurston

    2013-03-01

    Full Text Available Active restoration is one strategy to reverse tropical forest loss. Given the dynamic nature of climates, human populations, and other ecosystem components, the past practice of using historical reference sites as restoration targets is unlikely to result in self-sustaining ecosystems. Restoring sustainable ecological processes like pollination is a more feasible goal. We investigated how flower cover, planting design, and landscape forest cover influenced bird pollinator visits to Inga edulis trees in young restoration sites in Costa Rica. I. edulis trees were located in island plantings, where seedlings had been planted in patches, or in plantation plantings, where seedlings were planted to cover the restoration area. Sites were located in landscapes with scant (10–21% or moderate (35–76% forest cover. Trees with greater flower cover received more visits from pollinating birds; neither planting design nor landscape forest cover influenced the number of pollinator visits. Resident hummingbirds and a migratory bird species were the most frequent bird pollinators. Pollination in the early years following planting may not be as affected by details of restoration design as other ecological processes like seed dispersal. Future work to assess the quality of various pollinator species will be important in assessing this idea.

  8. Effects of Nonnative Ungulate Removal on Plant Communities and Soil Biogeochemistry in Tropical Forests

    Science.gov (United States)

    Cole, R. J.; Litton, C. M.; Giardina, C. P.; Sparks, J. P.

    2014-12-01

    Non-native ungulates have substantial impacts on native ecosystems globally, altering both plant communities and soil biogeochemistry. Across tropical and temperate ecosystems, land managers fence and remove non-native ungulates to conserve native biodiversity, a costly management action, yet long-term outcomes are not well quantified. Specifically, knowledge gaps include: (i) the magnitude and time frame of plant community recovery; (ii) the response of non-native invasive plants; and (iii) changes to soil biogeochemistry. In 2010, we established a series of paired ungulate presence vs. removal plots that span a 20 yr. chronosequence in tropical montane wet forests on the Island of Hawaii to quantify the impacts and temporal legacy of feral pig removal on plant communities and soil biogeochemistry. We also compared soil biogeochemistry in targeted areas of low and high feral pig impact. Our work shows that both native and non-native vegetation respond positively to release from top-down control following removal of feral pigs, but species of high conservation concern recover only if initially present at the time of non-native ungulate removal. Feral pig impacts on soil biogeochemistry appear to last for at least 20 years following ungulate removal. We observed that both soil physical and chemical properties changed with feral pig removal. Soil bulk density and volumetric water content decreased while extractable base cations and inorganic N increased in low vs. high feral pig impact areas. We hypothesize that altered soil biogeochemistry facilitates continued invasions by non-native plants, even decades after non-native ungulate removal. Future work will concentrate on comparisons between wet and dry forest ecosystems and test whether manipulation of soil nutrients can be used to favor native vs. non-native plant establishment.

  9. Incorporation of {sup 137}Cs by tropical tree species and its correlation with plant physiology

    Energy Technology Data Exchange (ETDEWEB)

    Cid, Alberto Silva; Anjos, Roberto Meigikos dos; Macario, K.D.; Veiga, R.; Ayubi, J. Juri; Lacerda, T. [Universidade Federal Fluminense (UFF), Niteroi, RJ (Brazil). Instituto de Fisica; Zamboni, C.B.; Medeiros, I.M.A. [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN- SP), Sao Paulo, SP (Brazil); Velasco, H.; Rizzotto, M. [Universidad Nacional de San Luis (UNSL) (Argentina). Instituto de Matematica Aplicada San Luis; Audicio, P. [Facultad de Ciencias (UDELAR), Montevideo (Uruguay). Centro de Investigaciones Nucleares

    2011-07-01

    Environmental phenomena associated with potential releases of radionuclides to terrestrial ecosystems have attracted the interest of several researches around the world. However, such interest has not been focused exclusively in its effects on human health. Several radionuclides have also been used as tracers of physicochemical or biological phenomena. These studies depend on both the development of auxiliary analysis techniques, which help to improve the results of traditional methods, and the production of additional data, so that a wide variety of natural processes can be understood. In this sense, the same radiometric results can be analyzed or interpreted from different viewpoints, allowing the interdisciplinary understanding of the overall structure of terrestrial ecosystems. {sup 137}Cs, for example, is one of the main fission products of nuclear reactors and atmospheric nuclear testing that is persistent in the biosphere because of its half-life of 30.2 years and biological mobility. This radionuclide remains in the top soil due to fixation and adsorption to clay minerals and organic matter, persisting in the root zone of plant for a long period of time. As its chemical behavior is similar to other monovalent inorganic cations (such as NH{sup +}{sub 4} , Na{sup +} and K{sup +}), Cs{sup +} can be readily absorbed by roots and translocated to the aboveground parts of plant. In this work, concentrations of {sup 137}Cs{sup +}, K{sup +} and Na{sup +} in fruits of lemon (Citrus limon B.) and coconut (Cocos nucifera L.) were measured by both gamma spectrometry and neutron activation analysis, with the aim to understand the behavior of monovalent inorganic cations in tropical plants as well as the plant ability to store these elements. In contrast to K{sup +} and Na{sup +}, Cs{sup +} is not an essential element to plants. However, our results have shown that {sup 137}Cs{sup +} incorporation to vegetal tissues is positively correlated to K{sup +} distribution inside

  10. 70 years of woody plants

    DEFF Research Database (Denmark)

    Leverenz, Jerry

    2006-01-01

    On 16 May the Arboretum in Hørsholm celebrates its 70th anniversary. There will be offering guided tours in the evening at 6.30 p.m.. Furthermore, the Arboretum is using the anniversary year to increase public knowledge of the Arboretum and of KVL....

  11. Volatile isoprenoids as defense compounds during abiotic stress in tropical plants

    Science.gov (United States)

    Jardine, K.

    2015-12-01

    Emissions of volatile isoprenoids from tropical forests play central roles in atmospheric processes by fueling atmospheric chemistry resulting in modified aerosol and cloud lifecycles and their associated feedbacks with the terrestrial biosphere. However, the identities of tropical isoprenoids, their biological and environmental controls, and functions within plants and ecosystems remain highly uncertain. As part of the DOE ARM program's GoAmazon 2014/15 campaign, extensive field and laboratory observations of volatile isoprenoids are being conducted in the central Amazon. Here we report the results of our completed and ongoing activities at the ZF2 forest reserve in the central Amazon. Among the results of the research are the suprisingly high abundance of light-dependent volatile isoprenoid emissions across abundant tree genera in the Amazon in both primary and secondary forests, the discovery of highly reactive monoterpene emissions from Amazon trees, and evidence for the importance of volatile isoprenoids in protecting photosynthesis during oxidative stress under elevated temperatures including energy consumption and direct antioxidant functions and a tight connection betwen volatile isoprenoid emissions, photorespiration, and CO2 recycling within leaves. The results highlight the need to model allocation of carbon to isoprenoids during elevated temperature stress in the tropics.

  12. Methyl halide fluxes from tropical plants under controlled radiation and temperature regimes

    Science.gov (United States)

    Blei, Emanuel; Yokouchi, Yoko; Saito, Takuya; Nozoe, Susumu

    2015-04-01

    Methyl halides (CH3Cl, CH3Br, CH3I) contribute significantly to the halogen burden of the atmosphere and have the potential to influence the stratospheric ozone layer through their catalytic effect in the Chapman cycle. As such they have been studied over the years, and many plants and biota have been examined for their potential to act as a source of these gases. One of the potentially largest terrestrial sources identified was tropical vegetation such as tropical ferns and Dipterocarp trees. Most of these studies concentrated on the identification and quantification of such fluxes rather than their characteristics and often the chambers used in these studies were either opaque or only partially transparent to the full solar spectrum. Therefore it is not certain to which degree emissions of methyl halides are innate to the plants and how much they might vary due to radiation or temperature conditions inside the enclosures. In a separate development it had been proposed that UV-radiation could cause live plant materials to be become emitters of methane even under non-anoxic conditions. As methane is chemically very similar to methyl halides and had been proposed to be produced from methyl-groups ubiquitously found in plant cell material there is a relatively good chance that such a production mechanism would also apply to methyl halides. To test whether radiation can affect elevated emissions of methyl halides from plant materials and to distinguish this from temperature effects caused by heat build-up in chambers a set of controlled laboratory chamber enclosures under various radiation and temperature regimes was conducted on four different tropical plant species (Magnolia grandiflora, Cinnamonum camphora, Cyathea lepifera, Angiopteris lygodiifolia), the latter two of which had previously been identified as strong methyl halide emitters. Abscised leaf samples of these species were subjected to radiation treatments such UV-B, UV-A and broad spectrum radiation

  13. STUDIES ON FUNCTIONAL BACTERIA OF INDONESIAN TROPICAL FOREST PLANTS FOR BIOREHABILITATION OF DEGRADED LANDS

    Directory of Open Access Journals (Sweden)

    Irnayuli R. Sitepu

    2008-06-01

    Full Text Available Forest  degradations  have left vast amount  of damaged  and abandoned  lands in Indonesia.   In this paper, we present our approaches  in rehabilitation of adverse soils using functional  bacteria isolated from plant species of Indonesian tropical  rain forests. For these purposes,  we collected  bacteria  from various  bio-geo-climatically different forests and conducted bioassays to test these bacterial abilities in improving plant growth. Repeated seedling-based studies on Shorea spp., Alstonia scholaris, Acacia crassicarpa, and Agathis lorantifolia have revealed that many bacteria were able to promote plant growth at early stage in the nursery.  Various  plant responses towards  inoculations suggested that although  forest soils maintain  highly diverse and potent  bacteria,  it is necessary to select appropriate approaches to obtain optimum  benefits from these plant-bacteria interactions.  Our  ideas and futures  studies  for further  management  of these plant- bacteria interactions for biorehabilitation are also discussed.

  14. Plant diversity patterns in neotropical dry forests and their conservation implications

    Science.gov (United States)

    K. Banda-R; A. Delgado-Salinas; K. G. Dexter; R. Linares-Palomino; A. Oliveira-Filho; D. Prado; M. Pullan; C. Quintana; R. Riina; G. M. Rodriguez M.; J. Weintritt; P. Acevedo-Rodriguez; J. Adarve; E. Alvarez; A. Aranguren B.; J. C. Arteaga; G. Aymard; A. Castano; N. Ceballos-Mago; A. Cogollo; H. Cuadros; F. Delgado; W. Devia; H. Duenas; L. Fajardo; A. Fernandez; M. A. Fernandez; J. Franklin; E. H. Freid; L. A. Galetti; R. Gonto; R. Gonzalez-M.; R. Graveson; E. H. Helmer; A. Idarraga; R. Lopez; H. Marcano-Vega; O. G. Martinez; H. M. Maturo; M. McDonald; K. McLaren; O. Melo; F. Mijares; V. Mogni; D. Molina; N. d. P. Moreno; J. M. Nassar; D. M. Neves; L. J. Oakley; M. Oatham; A. R. Olvera-Luna; F. F. Pezzini; O. J. R. Dominguez; M. E. Rios; O. Rivera; N. Rodriguez; A. Rojas; T. Sarkinen; R. Sanchez; M. Smith; C. Vargas; B. Villanueva; R. T. Pennington

    2016-01-01

    Seasonally dry tropical forests are distributed across Latin America and the Caribbean and are highly threatened, with less than 10% of their original extent remaining in many countries. Using 835 inventories covering 4660 species of woody plants, we show marked floristic turnover among inventories and regions, which may be higher than...

  15. Ontogenetic differences of herbivory on woody and herbaceous plants: a meta-analysis demonstrating unique effects of herbivory on the young and the old, the slow and the fast.

    Science.gov (United States)

    Massad, Tara Joy

    2013-05-01

    The effect of herbivory on plant performance is the subject of a large number of ecological studies, and plant responses to herbivory range from reduced reproduction to overcompensation. Because plant defenses, stored resources, and allocation demands change throughout a plant's lifetime, it can be hypothesized the effects of herbivory also vary with development. The present work extends previous analyses to incorporate hundreds of studies in a new meta-analysis addressing this topic. Herbivores had an overall negative effect on plant growth and reproduction, and, in contrast to a previous meta-analysis, this work shows the timing of herbivory is relevant. Differences in the effects of herbivory between life stages existed for woody plant reproduction and perennial herb growth. In addition, tree and shrub growth was reduced by herbivore damage at early ontogenetic stages, and perennial herb reproduction was limited by adult stage herbivory. These results partially support the continuum of an ontogenetic response model. Finally, consideration of this synthesis in conjunction with other work led to the conclusion that different plant groups optimize their defense investments in unique ways. Slow-growing plants may strongly chemically defend young tissues, supporting the plant-age hypothesis, because early herbivory is detrimental to growth. Faster-growing herbs may invest more in antiherbivore defense when they are older, supporting the growth-differentiation balance hypothesis, because later herbivory limits their reproduction.

  16. Plant invasions in protected areas of tropical pacific islands, with special reference to Hawaii

    Science.gov (United States)

    Hughes, R. Flint; Meyer, Jean-Yves; Loope, Lloyd L.

    2013-01-01

    Isolated tropical islands are notoriously vulnerable to plant invasions. Serious management for protection of native biodiversity in Hawaii began in the 1970s, arguably at Hawaii Volcanoes National Park. Concerted alien plant management began there in the 1980s and has in a sense become a model for protected areas throughout Hawaii and Pacific Island countries and territories. We review the relative successes of their strategies and touch upon how their experience has been applied elsewhere. Protected areas in Hawaii are fortunate in having relatively good resources for addressing plant invasions, but many invasions remain intractable, and invasions from outside the boundaries continue from a highly globalised society with a penchant for horticultural novelty. There are likely few efforts in most Pacific Islands to combat alien plant invasions in protected areas, but such areas may often have fewer plant invasions as a result of their relative remoteness and/or socio-economic development status. The greatest current needs for protected areas in this region may be for establishment of yet more protected areas, for better resources to combat invasions in Pacific Island countries and territories, for more effective control methods including biological control programme to contain intractable species, and for meaningful efforts to address prevention and early detection of potential new invaders.

  17. Power plant fuel switching and air quality in a tropical, forested environment

    Directory of Open Access Journals (Sweden)

    A. S. S. Medeiros

    2017-07-01

    Full Text Available How a changing energy matrix for electricity production affects air quality is considered for an urban region in a tropical, forested environment. Manaus, the largest city in the central Amazon Basin of Brazil, is in the process of changing its energy matrix for electricity production from fuel oil and diesel to natural gas over an approximately 10-year period, with a minor contribution by hydropower. Three scenarios of urban air quality, specifically afternoon ozone concentrations, were simulated using the Weather Research and Forecasting (WRF-Chem model. The first scenario used fuel oil and diesel for electricity production, which was the reality in 2008. The second scenario was based on the fuel mix from 2014, the most current year for which data were available. The third scenario considered nearly complete use of natural gas for electricity production, which is the anticipated future, possibly for 2018. For each case, inventories of anthropogenic emissions were based on electricity generation, refinery operations, and transportation. Transportation and refinery operations were held constant across the three scenarios to focus on effects of power plant fuel switching in a tropical context. The simulated NOx and CO emissions for the urban region decrease by 89 and 55 %, respectively, after the complete change in the energy matrix. The results of the simulations indicate that a change to natural gas significantly decreases maximum afternoon ozone concentrations over the population center, reducing ozone by > 70 % for the most polluted days. The sensitivity of ozone concentrations to the fuel switchover is consistent with a NOx-limited regime, as expected for a tropical forest having high emissions of biogenic volatile organic compounds, high water vapor concentrations, and abundant solar radiation. There are key differences in a shifting energy matrix in a tropical, forested environment compared to other world environments. Policies

  18. Tropical Glaciers

    Science.gov (United States)

    Fountain, Andrew

    The term "tropical glacier" calls to mind balmy nights and palm trees on one hand and cold, blue ice on the other. Certainly author Gabriel Garcia Marqez exploited this contrast in One Hundred Years of Solitude. We know that tropical fish live in warm, Sun-kissed waters and tropical plants provide lush, dense foliage populated by colorful tropical birds. So how do tropical glaciers fit into this scene? Like glaciers everywhere, tropical glaciers form where mass accumulation—usually winter snow—exceeds mass loss, which is generally summer melt. Thus, tropical glaciers exist at high elevations where precipitation can occur as snowfall exceeds melt and sublimation losses, such as the Rwenzori Mountains in east Africa and the Maoke Range of Irian Jaya.

  19. Sensitivity of woody carbon stocks to bark investment strategy in Neotropical savannas and forests

    Science.gov (United States)

    Trugman, Anna T.; Medvigy, David; Hoffmann, William A.; Pellegrini, Adam F. A.

    2018-01-01

    Fire frequencies are changing in Neotropical savannas and forests as a result of forest fragmentation and increasing drought. Such changes in fire regime and climate are hypothesized to destabilize tropical carbon storage, but there has been little consideration of the widespread variability in tree fire tolerance strategies. To test how aboveground carbon stocks change with fire frequency and composition of plants with different fire tolerance strategies, we update the Ecosystem Demography model 2 (ED2) with (i) a fire survivorship module based on tree bark thickness (a key fire-tolerance trait across woody plants in savannas and forests), and (ii) plant functional types representative of trees in the region. With these updates, the model is better able to predict how fire frequency affects population demography and aboveground woody carbon. Simulations illustrate that the high survival rate of thick-barked, large trees reduces carbon losses with increasing fire frequency, with high investment in bark being particularly important in reducing losses in the wettest sites. Additionally, in landscapes that frequently burn, bark investment can broaden the range of climate and fire conditions under which savannas occur by reducing the range of conditions leading to either complete tree loss or complete grass loss. These results highlight that tropical vegetation dynamics depend not only on rainfall and changing fire frequencies but also on tree fire survival strategy. Further, our results indicate that fire survival strategy is fundamentally important in regulating tree size demography in ecosystems exposed to fire, which increases the preservation of aboveground carbon stocks and the coexistence of different plant functional groups.

  20. UV Screening in Native and Non-native Plant Species in the Tropical Alpine: Implications for Climate Change-Driven Migration of Species to Higher Elevations

    Directory of Open Access Journals (Sweden)

    Paul W. Barnes

    2017-08-01

    Full Text Available Ongoing changes in Earth’s climate are shifting the elevation ranges of many plant species with non-native species often experiencing greater expansion into higher elevations than native species. These climate change-induced shifts in distributions inevitably expose plants to novel biotic and abiotic environments, including altered solar ultraviolet (UV-B (280–315 nm radiation regimes. Do the greater migration potentials of non-native species into higher elevations imply that they have more effective UV-protective mechanisms than native species? In this study, we surveyed leaf epidermal UV-A transmittance (TUV A in a diversity of plant species representing different growth forms to test whether native and non-native species growing above 2800 m elevation on Mauna Kea, Hawaii differed in their UV screening capabilities. We further compared the degree to which TUV A varied along an elevation gradient in the native shrub Vaccinium reticulatum and the introduced forb Verbascum thapsus to evaluate whether these species differed in their abilities to adjust their levels of UV screening in response to elevation changes in UV-B. For plants growing in the Mauna Kea alpine/upper subalpine, we found that adaxial TUV A, measured with a UVA-PAM fluorometer, varied significantly among species but did not differ between native (mean = 6.0%; n = 8 and non-native (mean = 5.8%; n = 11 species. When data were pooled across native and non-native taxa, we also found no significant effect of growth form on TUV A, though woody plants (shrubs and trees were represented solely by native species whereas herbaceous growth forms (grasses and forbs were dominated by non-native species. Along an elevation gradient spanning 2600–3800 m, TUV A was variable (mean range = 6.0–11.2% and strongly correlated with elevation and relative biologically effective UV-B in the exotic V. thapsus; however, TUV A was consistently low (3% and did not vary with elevation in the native

  1. Functional strategies of tropical dry forest plants in relation to growth form and isotopic composition

    Science.gov (United States)

    Santiago, L. S.; Silvera, K.; Andrade, J. L.; Dawson, T. E.

    2017-11-01

    Tropical dry forests (TDFs) undergo a substantial dry season in which plant species must endure several months of drought. Although TDFs support a diverse array of plant growth forms, it is not clear how they vary in mechanisms for coping with seasonal drought. We measured organic tissue stable isotopic composition of carbon (δ13C) and nitrogen (δ15N) across six plant growth forms including epiphytes, terrestrial succulents, trees, shrubs, herbs, and vines, and oxygen (δ18O) of four growth forms, to distinguish among patterns of resource acquisition and evaluate mechanisms for surviving annual drought in a lowland tropical dry forest in Yucatan, Mexico. Terrestrial succulent and epiphyte δ13C was around -14‰, indicating photosynthesis through the Crassulacean acid metabolism pathway, and along with one C4 herb were distinct from mean values of all other growth forms, which were between -26 and -29‰ indicating C3 photosynthesis. Mean tissue δ15N across epiphytes was -4.95‰ and was significantly lower than all other growth forms, which had values around +3‰. Tissue N concentration varied significantly among growth forms with epiphytes and terrestrial succulents having significantly lower values of about 1% compared to trees, shrubs, herbs and vines, which were around 3%. Tissue C concentration was highest in trees, shrubs and vines, intermediate in herbs and epiphytes and lowest in terrestrial succulents. δ18O did not vary among growth forms. Overall, our results suggest several water-saving aspects of resource acquisition, including the absolute occurrence of CAM photosynthesis in terrestrial succulents and epiphytes, high concentrations of leaf N in some species, which may facilitate CO2 drawdown by photosynthetic enzymes for a given stomatal conductance, and potentially diverse N sources ranging from atmospheric N in epiphytes with extremely depleted δ15N values, and a large range of δ15N values among trees, many of which are legumes and dry season

  2. Reasons for an outstanding plant diversity in the tropical Andes of Southern Ecuador

    Directory of Open Access Journals (Sweden)

    Michael Richter

    2009-06-01

    Full Text Available Long-term field studies in the scope of a multidisciplinary project in southern Ecuador revealed extraordinary high species numbers of many organismic groups. This article discusses reasons for the outstanding vascular plant diversity using a hierarchical scale-oriented top-down approach (Grüninger 2005, from the global scale to the local microscale. The global scale explains general (paleo- ecological factors valid for most parts of the humid tropics, addressing various hypotheses and theories, such as the “greater effective evolutionary time”, constant input of “accidentals”, the “seasonal variability hypothesis”, the “intermediate disturbance hypothesis”, and the impact of soil fertility. The macroscale focuses on the Andes in northwestern South America. The tropical Andes are characterised by many taxa of restricted range which is particularly true for the Amotape-Huancabamba region, i.e. the so called Andean Depression, which is effective as discrete phytogeographic transition as well as barrier zone. Interdigitation of northern and southern flora elements, habitat fragmentation, geological and landscape history, and a high speciation rate due to rapid genetic radiation of some taxa contribute to a high degree of diversification. The mesoscale deals with the special environmental features of the eastern mountain range, the Cordillera Real and surrounding areas in southern Ecuador. Various climatic characteristics, the orographic heterogeneity, the geologic and edaphic conditions as well as human impact are the most prominent factors augmenting plant species diversity. On microscale, prevailing regimes of disturbance and environmental stresses, the orographic basement, as well as the general role on the various mountain chains are considered. Here, micro-habitats e.g. niches for epiphytes, effects of micro-relief patterns, and successions after small-sized disturbance events are screened. Direct effects of human impact are

  3. Radiocesium contamination behavior and its effect on potassium absorption in tropical or subtropical plants

    Energy Technology Data Exchange (ETDEWEB)

    Carvalho, C. [Instituto de Fisica, Universidade Federal Fluminense, Av. Litoranea s/n, Gragoata, Niteroi, Rio de Janeiro, Cep 24210-340 (Brazil); Anjos, R.M. [Instituto de Fisica, Universidade Federal Fluminense, Av. Litoranea s/n, Gragoata, Niteroi, Rio de Janeiro, Cep 24210-340 (Brazil)]. E-mail: meigikos@if.uff.br; Mosquera, B. [Instituto de Fisica, Universidade Federal Fluminense, Av. Litoranea s/n, Gragoata, Niteroi, Rio de Janeiro, Cep 24210-340 (Brazil); Macario, K. [Instituto de Fisica, Universidade Federal Fluminense, Av. Litoranea s/n, Gragoata, Niteroi, Rio de Janeiro, Cep 24210-340 (Brazil); Veiga, R. [Instituto de Fisica, Universidade Federal Fluminense, Av. Litoranea s/n, Gragoata, Niteroi, Rio de Janeiro, Cep 24210-340 (Brazil)

    2006-07-01

    The accumulation and long-term decline of radiocesium contamination in tropical plant species was studied through measurements of gamma-ray spectra from pomegranate (Punica granatum) and chili pepper (Capsicum fructescens) trees. The plants were originally grown at a {sup 137}Cs contaminated site (where a radiological accident occurred in the city of Goiania, Brazil, in 1987), and transplanted to uncontaminated soil, so that the main source of contamination of the new leaves and fruits would be the fraction of the available radiocesium in the body of the plants. Measurements of {sup 137}Cs and {sup 4}K concentrations along the roots, main trunk, twigs, leaves and fruits before and after the transplant process of both plant species indicated a direct competition between Cs and K ions, suggesting that these elements could have a common accumulation mechanism. Cesium transfer factors from soil to pomegranate, green and red chili pepper fruits were evaluated as 0.4 {+-} 0.1, 0.06 {+-} 0.01 and 0.05 {+-} 0.01, respectively. Biological half-life values due to {sup 137}Cs translocation from the tree reservoir (BHL{sub T}) were calculated as 0.30 years for pomegranate, 0.12 years and 0.07 years for red and green peppers, respectively.

  4. Radiocesium contamination behavior and its effect on potassium absorption in tropical or subtropical plants

    International Nuclear Information System (INIS)

    Carvalho, C.; Anjos, R.M.; Mosquera, B.; Macario, K.; Veiga, R.

    2006-01-01

    The accumulation and long-term decline of radiocesium contamination in tropical plant species was studied through measurements of gamma-ray spectra from pomegranate (Punica granatum) and chili pepper (Capsicum fructescens) trees. The plants were originally grown at a 137 Cs contaminated site (where a radiological accident occurred in the city of Goiania, Brazil, in 1987), and transplanted to uncontaminated soil, so that the main source of contamination of the new leaves and fruits would be the fraction of the available radiocesium in the body of the plants. Measurements of 137 Cs and 4 K concentrations along the roots, main trunk, twigs, leaves and fruits before and after the transplant process of both plant species indicated a direct competition between Cs and K ions, suggesting that these elements could have a common accumulation mechanism. Cesium transfer factors from soil to pomegranate, green and red chili pepper fruits were evaluated as 0.4 ± 0.1, 0.06 ± 0.01 and 0.05 ± 0.01, respectively. Biological half-life values due to 137 Cs translocation from the tree reservoir (BHL T ) were calculated as 0.30 years for pomegranate, 0.12 years and 0.07 years for red and green peppers, respectively

  5. Patterns and correlates of plant diversity differ between common and rare species in a neotropical dry forest

    NARCIS (Netherlands)

    Tetetla-Rangel, Erika; Dupuy, Juan Manuel; Hernández-Stefanoni, José Luis; Hoekstra, Paul H.

    2017-01-01

    Determining which factors affect species richness is important for conservation theory and practice. However, richness of common and rare species may be affected by different factors. We use an extensive inventory of woody plants from a tropical dry forest landscape in Yucatan, Mexico to assess the

  6. Extreme meteorological events in nuclear power plant siting, excluding tropical cyclones

    International Nuclear Information System (INIS)

    1981-01-01

    This Safety Guide deals with the extremes of meteorological variables and the extreme meteorological phenomena in accordance with the general criteria of the Code. The Guide outlines a procedure based on the following steps: (1) The meteorological phenomena and variables are described and classified, according to their effects on safety. (2) Data sources are identified, and data are collected. (3) Meteorological variables such as air temperature are analysed to determine their design bases; and the design basis event in case of phenomena such as the design basis tornado is identified. (4) As appropriate, the design basis value for the variable, or the design basis for the phenomena (such as pressure drop and maximum wind speed of the design basis tornado), is defined. In the following sections, the general procedure for evaluating the design bases of extreme meteorological variables and phenomena is outlined. The procedure is then presented in detail for each variable or phenomenon considered. The variables characterizing the meteorological environment dealt with in this Guide are wind speed, atmospheric precipitation, and temperature. The extreme meteorological phenomena discussed here are the tornado and, briefly, the tropical cyclone, which is discussed more extensively in the Safety Guide on Design Basis Tropical Cyclone for Nuclear Power Plants (IAEA Safety Series No. 50-SG-S11B)

  7. Determination of some elements in Ageratum conyziodes, a tropical medicinal plant, using instrumental neutron activation analysis

    International Nuclear Information System (INIS)

    Dim, L.A.; Funtua, I.I.; Umar, I.M.; Gwozdz, R.

    2004-01-01

    Instrumental neutron activation analysis was utilized for the multielemental determination of elements in the roots of Ageratum conyzoides, a tropical medicinal plant that is used locally for the cure of various diseases in Nigeria. The concentrations of Al, Ba, Br, Ca, Co, Cr, Fe, K, Mg, Mn, Na, Rb, Sc, Sr, V and Zn were analyzed with the 250 kW Triga Reactor at the Atominstitut, Vienna. The essential elements K, Na, Ca, Fe, Mg, Mn and Zn and the non-essential elements Al, Ba, Sr and Rb are present in significant concentrations. Other elements including Co, Cr, Sc and V are present at trace levels. The likely implication of these elements in restoring and maintaining good health is discussed. Quality control on the measurements was carried out by analyzing standard reference materials alongside the samples. (author)

  8. Oligarchic forests of economic plants in amazonia: utilization and conservation of an important tropical resource.

    Science.gov (United States)

    Peters, C M; Balick, M J; Kahn, F; Anderson, A B

    1989-12-01

    Tropical forests dominated by only one or two tree species occupy tens of millions of hectares in Ammonia In many cases, the dominant species produce fruits, seeds, or oils of economic importance. Oligarchic (Gr. oligo = few, archic = dominated or ruled by) forests of six economic species, i. e., Euterpe oleracea, Grias peruviana, Jessenia bataua, Mauritia flexuosa, Myrciaria dubia, and Orbignya phalerata, were studied in Brazil and Peru Natural populations of these species contain from 100 to 3,000 conspecific adult trees/ha and produce up to 11.1 metric tons of fruit/hd/yr. These plant populations are utilized and occasionally managed, by rural inhabitants in the region. Periodic fruit harvests, if properly controlled have only a minimal impact on forest structure and function, yet can generate substantial economic returns Market-oriented extraction of the fruits produced by oligarchic forests appears to represent a promising alternative for reconciling the development and conservation of Amazonian forests.

  9. Plant phylogeny as a window on the evolution of hyperdiversity in the tropical rainforest biome.

    Science.gov (United States)

    Eiserhardt, Wolf L; Couvreur, Thomas L P; Baker, William J

    2017-06-01

    I. II. III. IV. V. VI. VII. VIII. IX. References SUMMARY: Tropical rainforest (TRF) is the most species-rich terrestrial biome on Earth, harbouring just under half of the world's plant species in c. 7% of the land surface. Phylogenetic trees provide important insights into mechanisms underpinning TRF hyperdiversity that are complementary to those obtained from the fossil record. Phylogenetic studies of TRF plant diversity have mainly focused on whether this biome is an evolutionary 'cradle' or 'museum', emphasizing speciation and extinction rates. However, other explanations, such as biome age, immigration and ecological limits, must also be considered. We present a conceptual framework for addressing the drivers of TRF diversity, and review plant studies that have tested them with phylogenetic data. Although surprisingly few in number, these studies point to old age of TRF, low extinction and high speciation rates as credible drivers of TRF hyperdiversity. There is less evidence for immigration and ecological limits, but these cannot be dismissed owing to the limited number of studies. Rapid methodological developments in DNA sequencing, macroevolutionary analysis and the integration of phylogenetics with other disciplines may improve our grasp of TRF hyperdiversity in the future. However, such advances are critically dependent on fundamental systematic research, yielding numerous, additional, well-sampled phylogenies of TRF lineages. © 2017 The Authors. New Phytologist © 2017 New Phytologist Trust.

  10. INTAKE OF TROPICAL TANNINIFEROUS PLANTS BY GOATS AND SHEEP WHEN OFFERED AS A SOLE FEED

    Directory of Open Access Journals (Sweden)

    Miguel A. Alonso-Díaz

    2009-06-01

    Full Text Available The intake of tropical tanniniferous plants (TTP (Lysiloma latisiliquum, Piscidia piscipula and Acacia pennatula when offered as a single feed to small ruminants could help to design a supplementation strategy looking for an anthelmintic effect. The objectives of the current study were: i to determine the chemical composition of TTP offered to goats and sheep, ii to determine and compare the total intake of TTP when offered as a single feed to goats and sheep. Adult sheep and goats, with experience in the intake of TTP, were allocated to individual pens. Three consecutive experimental period (15 d separated by seven days were used. Each period consisted of 10 d adaptation and 5 days of experiment. During adaptation animals received 40 g of leaves of each TTP plant, fresh grass and concentrate feed on a daily basis. During the experimental period animals were fed ad libitum only with the fodder of a sole TTP. Between each period, animals were fed with fresh grass (ad libitum and concentrate (200 g-1 day. Crude protein (CP, neutral detergent fiber (NDF, acid detergent fiber (ADF and lignin (L were determined from each TTP. Total polyphenols (TP, total tannins (TT and condensed tannins (CT were also determined. During each experimental period, refused fodder and intake were measured every 24 h. A multivariate analysis was used in order to determine the effect of factors (animal species, plant species and individual animal within specie on the dry matter intake. Factors with statistical effect (P

  11. Thermal performance of different planting substrates and irrigation frequencies in extensive tropical rooftop greeneries

    Energy Technology Data Exchange (ETDEWEB)

    Lin, Yi-Jiung [Department of Environmental Engineering and Science, Foo-Yin University, Kaohsiung (China); No. 16, Lane 29, Chen-Sing 7th Street, Niao-Song, Kaohsiung 833 (China); Lin, Hsien-Te [Department of Architecture, National Cheng Kung University, Tainan (China); No. 1, Ta-Hsueh Road, Tainan 701 (China)

    2011-02-15

    The need for the better use of scarce planetary resources has never been more evident than it is today. However, this need is poorly reflected in human housing. In recent years, there has been a growing realization of the importance of constructing human shelters that better conserve energy and water through appropriate insulation and architectural designs. Among the important advancements in these areas is the use of rooftop greeneries for both energy and water conservation. This paper performs an investigation into this topic within the specific climatic context of tropical regions. Long-term experimental results are provided from a four-floor building in Kaohsiung in the southern part of Taiwan. The study involves a fully monitored extensive rooftop greenery and examines four different plant substrates, three different irrigation regimes, and different types of drought-enduring plants to find the most efficient combination of all three in providing maximum heat insulation and water usage efficiency. The attenuation of solar radiation through the vegetation layer is evaluated, as well as the thermal insulation performance of the rooftop greenery structure. Among the substrates, burned sludge has the best thermal reduction percentage of heat amplitude under the roof slab surface (up to 84.4%). Irrigation twice a week has the best thermal reduction percentage of heat amplitude (91.6%). Among the plant types, Sansevieria trifasciata cv. Laurentii Compacta and Rhoeo spathaceo cv. Compacta are found to be suitable for extensive rooftop greeneries because they have the best coverage ratio and are most drought enduring. (author)

  12. Soil to plant transfer values of 137 Cs in soils of tropical agro-ecological systems

    International Nuclear Information System (INIS)

    Wasserman, Maria Angelica; Ferreira, Ana Cristina Melo; Conti, Claudio Carvalho; Rochedo, Elaine Rua Rodriguez; Bartoly, Flavia; Viana, Aline Gonzalez; Moura, Glaucio Pereira; Poquet, Isabel; Perez, Daniel Vidal

    2002-01-01

    Recent radioecological studies have showed that some ecosystems present more suitable conditions for soil to plant transfer of some radionuclides, while others present lower transfer when compared with average values. Due to the difficulty to generate, experimentally, soil to plant transfer factors enough to cover the totality of existing soil and vegetation types, an alternative way has been the use of soil to reference plant transfer factor determined in various ecosystems. Trough the use of conversion factors, the reference transfer factor can be converted in values of transfer factor specific for a specific type of crop. These values can be used regionally to improve dose calculation and models for radiological risk assessments. This work presents experimental data for 137 Cs for reference crops grown up in Oxisol, Ultisol and Alfisol. These results allow the assessment of sensibility of main Brazilian soils regarding a radiological contamination with 137 Cs and provide regional parameters values. The results obtained in soils of tropical climate validate the international methodology aiming to derive generic transfer factor values for 137 Cs in reference crops based on a few soil properties such as fertility, pH and organic matter content. (author)

  13. Plant delta 15N correlates with the transpiration efficiency of nitrogen acquisition in tropical trees.

    Science.gov (United States)

    Cernusak, Lucas A; Winter, Klaus; Turner, Benjamin L

    2009-11-01

    Based upon considerations of a theoretical model of (15)N/(14)N fractionation during steady-state nitrate uptake from soil, we hypothesized that, for plants grown in a common soil environment, whole-plant delta(15)N (deltaP) should vary as a function of the transpiration efficiency of nitrogen acquisition (F(N)/v) and the difference between deltaP and root delta(15)N (deltaP - deltaR). We tested these hypotheses with measurements of several tropical tree and liana species. Consistent with theoretical expectations, both F(N)/v and deltaP - deltaR were significant sources of variation in deltaP, and the relationship between deltaP and F(N)/v differed between non-N(2)-fixing and N(2)-fixing species. We interpret the correlation between deltaP and F(N)/v as resulting from variation in mineral nitrogen efflux-to-influx ratios across plasma membranes of root cells. These results provide a simple explanation of variation in delta(15)N of terrestrial plants and have implications for understanding nitrogen cycling in ecosystems.

  14. Nectar-living yeasts of a tropical host plant community: diversity and effects on community-wide floral nectar traits

    Science.gov (United States)

    2017-01-01

    We characterize the diversity of nectar-living yeasts of a tropical host plant community at different hierarchical sampling levels, measure the associations between yeasts and nectariferous plants, and measure the effect of yeasts on nectar traits. Using a series of hierarchically nested sampling units, we extracted nectar from an assemblage of host plants that were representative of the diversity of life forms, flower shapes, and pollinator types in the tropical area of Yucatan, Mexico. Yeasts were isolated from single nectar samples; their DNA was identified, the yeast cell density was estimated, and the sugar composition and concentration of nectar were quantified using HPLC. In contrast to previous studies from temperate regions, the diversity of nectar-living yeasts in the plant community was characterized by a relatively high number of equally common species with low dominance. Analyses predict highly diverse nectar yeast communities in a relatively narrow range of tropical vegetation, suggesting that the diversity of yeasts will increase as the number of sampling units increases at the level of the species, genera, and botanical families of the hosts. Significant associations between specific yeast species and host plants were also detected; the interaction between yeasts and host plants impacted the effect of yeast cell density on nectar sugars. This study provides an overall picture of the diversity of nectar-living yeasts in tropical host plants and suggests that the key factor that affects the community-wide patterns of nectar traits is not nectar chemistry, but rather the type of yeasts interacting with host plants. PMID:28717591

  15. Nectar-living yeasts of a tropical host plant community: diversity and effects on community-wide floral nectar traits

    Directory of Open Access Journals (Sweden)

    Azucena Canto

    2017-07-01

    Full Text Available We characterize the diversity of nectar-living yeasts of a tropical host plant community at different hierarchical sampling levels, measure the associations between yeasts and nectariferous plants, and measure the effect of yeasts on nectar traits. Using a series of hierarchically nested sampling units, we extracted nectar from an assemblage of host plants that were representative of the diversity of life forms, flower shapes, and pollinator types in the tropical area of Yucatan, Mexico. Yeasts were isolated from single nectar samples; their DNA was identified, the yeast cell density was estimated, and the sugar composition and concentration of nectar were quantified using HPLC. In contrast to previous studies from temperate regions, the diversity of nectar-living yeasts in the plant community was characterized by a relatively high number of equally common species with low dominance. Analyses predict highly diverse nectar yeast communities in a relatively narrow range of tropical vegetation, suggesting that the diversity of yeasts will increase as the number of sampling units increases at the level of the species, genera, and botanical families of the hosts. Significant associations between specific yeast species and host plants were also detected; the interaction between yeasts and host plants impacted the effect of yeast cell density on nectar sugars. This study provides an overall picture of the diversity of nectar-living yeasts in tropical host plants and suggests that the key factor that affects the community-wide patterns of nectar traits is not nectar chemistry, but rather the type of yeasts interacting with host plants.

  16. CHROMOSOMES OF WOODY SPECIES

    Directory of Open Access Journals (Sweden)

    Julio R Daviña

    2000-01-01

    Full Text Available Chromosome numbers of nine subtropical woody species collected in Argentina and Paraguay are reported. The counts tor Coutarea hexandra (2n=52, Inga vera subsp. affinis 2n=26 (Fabaceae and Chorisia speciosa 2n=86 (Bombacaceae are reported for the first time. The chromosome number given for Inga semialata 2n=52 is a new cytotype different from the previously reported. Somatic chromosome numbers of the other taxa studied are: Sesbania punicea 2n=12, S. virgata 2n=12 and Pilocarpus pennatifolius 2n=44 from Argentina

  17. Experimental defoliation affects male but not female reproductive performance of the tropical monoecious plant Croton suberosus (Euphorbiaceae).

    Science.gov (United States)

    Narbona, Eduardo; Dirzo, Rodolfo

    2010-08-01

    Monoecious plants have the capacity to allocate resources separately to male and female functions more easily than hermaphrodites. This can be advantageous against environmental stresses such as leaf herbivory. However, studies showing effects of herbivory on male and female functions and on the interaction with the plant's pollinators are limited, particularly in tropical plants. Here, the effects of experimental defoliation were examined in the monoecious shrub Croton suberosus (Euphorbiaceae), a wasp-pollinated species from a Mexican tropical dry forest. Three defoliation treatments were applied: 0 % (control), 25 % (low) or 75 % (high) of plant leaf area removed. Vegetative (production of new leaves) and reproductive (pistillate and staminate flower production, pollen viability, nectar production, fruit set, and seed set) performance variables, and the abundance and activity of floral visitors were examined. Defoliated plants overcompensated for tissue loss by producing more new leaves than control plants. Production of staminate flowers gradually decreased with increasing defoliation and the floral sex ratio (staminate : pistillate flowers) was drastically reduced in high-defoliation plants. In contrast, female reproductive performance (pistillate flower production, fruit set and seed set) and pollinator visitation and abundance were not impacted by defoliation. The asymmetrical effects of defoliation on male and female traits of C. suberosus may be due to the temporal and spatial flexibility in the allocation of resources deployed by monoecious plants. We posit that this helps to maintain the plant's pollination success in the face of leaf herbivory stress.

  18. Woody biomass logistics [Chapter 14

    Science.gov (United States)

    Robert Keefe; Nathaniel Anderson; John Hogland; Ken Muhlenfeld

    2014-01-01

    The economics of using woody biomass as a fuel or feedstock for bioenergy applications is often driven by logistical considerations. Depending on the source of the woody biomass, the acquisition cost of the material is often quite low, sometimes near zero. However, the cost of harvesting, collection, processing, storage, and transportation from the harvest site to end...

  19. Tritium behavior pattern in some soil-plant systems in a tropical environment

    International Nuclear Information System (INIS)

    Soman, S.D.; Iyengar, T.S.; Sadarangani, S.H.; Vaze, P.K.

    1975-01-01

    A study of the distribution pattern of tritium in the soil/plant environment gives valuable ecological information on the natural water balance. The results of such a study for the conditions obtaining in India are given in this paper. Field studies are carried out by injection of tritium into some soil/plant systems and following the transfer pathways. The method of extraction for tissue-free-water-tritium (TFWT) is based on the vacuum freeze-drying technique while the tissue-bound-tritium (TBT) is estimated by a modified version of the Shoniger method. The determination of residence time of tritium in aqueous and organic phase in a number of tropical trees has been carried out both for stem-injection as well as intake from the soil. From the results of this study the tree biomass and transpiration rates have been determined. The tritium profile over time, for an acute exposure in certain trees such as Morinda Tinetoria, Achras Sapota etc. shows significantly different patterns compared to the normal pattern shown by Mangifera Indica, Terminalia Catappa, Ficus Glomerata etc. The period of investigation in each case varied from 400 to 1000 h. In most of the cases, the TBT fractions were very low compared to TFWT fractions in the initial stages. The tritium behavior in the tree reflects significant characteristics of the tritium behavior in the soil system. The authors have found that the leaf sampling can be used as an indicator of total environmental tritium behavior. (author)

  20. Vasorelaxation induced by common edible tropical plant extracts in isolated rat aorta and mesenteric vascular bed.

    Science.gov (United States)

    Runnie, I; Salleh, M N; Mohamed, S; Head, R J; Abeywardena, M Y

    2004-06-01

    In this study, the vasodilatory actions of nine edible tropical plant extracts were investigated. Ipomoea batatas (sweet potato leaf), Piper betle (betel leaf), Anacardium occidentale (cashew leaf), Gynandropsis gynandra (maman leaf), Carica papaya (papaya leaf), and Mentha arvensis (mint leaf) extracts exhibited more than 50% relaxing effect on aortic ring preparations, while Piper betle and Cymbopogon citratus (lemongrass stalk) showed comparable vasorelaxation on isolated perfused mesenteric artery preparation. The vascular effect on the aortic ring preparations were mainly endothelium-dependent, and mediated by nitric oxide (NO) as supported by the inhibition of action in the presence of N(omega)-nitro-L-arginine (NOLA), an nitric oxide synthase (NOS) inhibitor, or by the removal of endothelium. In contrast, vasodilatory actions in resistance vessels (perfused mesenteric vascular beds) appear to involve several biochemical mediators, including NO, prostanoids, and endothelium-dependent hyperpolarizing factors (EDHFs). Total phenolic contents and antioxidant capacities varied among different extracts and found to be independent of vascular relaxation effects. This study demonstrates that many edible plants common in Asian diets to possess potential health benefits, affording protection at the vascular endothelium level.

  1. EFFECT OF COVER CROPS ON SOIL ATTRIBUTES, PLANT NUTRITION, AND IRRIGATED TROPICAL RICE YIELD

    Directory of Open Access Journals (Sweden)

    ANDRE FROES DE BORJA REIS

    2017-01-01

    Full Text Available In flood plains, cover crops are able to alter soil properties and significantly affect rice nutrition and yield. The aims of this study were to determine soil properties, plant nutrition, and yield of tropical rice cultivated on flood plains after cover crop cultivation with conventional tillage (CT and no-tillage system (NTS at low and high nitrogen (N fertilization levels. The experimental design was a randomized block in a split-split-plot scheme with four replications. In the main plots were cover crops sunhemp (Crotalaria juncea and C. spectabilis, velvet bean (Mucuna aterrima, jackbean (Canavalia ensiformis, pigeon pea (Cajanus cajan, Japanese radish (Raphanus sativus, cowpea (Vigna unguiculata and a fallow field. In the subplots were the tillage systems (CT or NTS. The nitrogen fertilization levels in the sub-subplots were (10 kg N ha-1 and 45 kg N ha-1. All cover crops except Japanese radish significantly increased mineral soil nitrogen and nitrate concentrations. Sunhemp, velvet bean, and cowpea significantly increased soil ammonium content. The NTS provides higher mineral nitrogen and ammonium content than that by CT. Overall, cover crops provided higher levels of nutrients to rice plants in NTS than in CT. Cover crops provide greater yield than fallow treatments. Rice yield was higher in NTS than in CT, and greater at a higher rather than lower nitrogen fertilization level.

  2. Soil-to-plant transfer of radiocaesium for selected tropical plant species in Bangladesh

    International Nuclear Information System (INIS)

    Rahman, M.M.; Rahman, M.M.; Koddus, A.; Ahmad, G.U.; Voigt, G.

    2005-01-01

    Soil-to-plant transfer factors (TF) of radiocaesium ( 137 Cs) were determined under field condition for grassy vegetation grown in Bangladesh at contaminated land in the Atomic Energy Research Establishment (AERE) campus. TF values for rice, grass and grassy/root vegetations grown in the same type of soil were also measured under pot condition. TF values of 137 Cs for grassy vegetation (2.4 x 10 -2 -4.2 x 10 -2 with an average of 3.1 x 10 -2 ± 0.005) obtained under field condition were slightly lower than the values for grass and grassy/root vegetations (2.9 x 10 -2 -6.6 x 10 -2 with an average of 4.8 x 10 -2 ± 0.01 for grass and grassy vegetations and 2.3 x 10 -2 -5.6 x 10 -2 with an average of 4.0 x 10 -2 ± 0.009 for root vegetations, respectively) obtained under pot condition. However, TF values (9.0 x 10 -3 -2.6 x 10 -2 with an average of 1.9 x 10 -2 ± 0.004) obtained for rice were about a factor of 4 lower than the values obtained for grass and grassy/root vegetations. When the properties of the AERE soils as input parameters were used in the soil-plant transfer model of Absalom, the estimated TF values (4.5 x 10 -2 -6.7 x 10 -2 with an average of 5.3 x 10 -2 ± 0.006) were consistent with the measured values obtained for grass and grassy vegetations under pot condition, however, the model overestimates the TF values for rice

  3. Stable carbon, oxygen, and nitrogen, isotope analysis of plants from a South Asian tropical forest: Implications for primatology.

    Science.gov (United States)

    Roberts, Patrick; Blumenthal, Scott A; Dittus, Wolfgang; Wedage, Oshan; Lee-Thorp, Julia A

    2017-06-01

    Stable isotope analysis of primate tissues in tropical forest contexts is an increasingly popular means of obtaining information about niche distinctions among sympatric species, including preferences in feeding height, forest canopy density, plant parts, and trophism. However, issues of equifinality mean that feeding height, canopy density, as well as the plant parts and plant species consumed, may produce similar or confounding effects. With a few exceptions, researchers have so far relied largely on general principles and/or limited plant data from the study area as references for deducing the predominant drivers of primate isotope variation. Here, we explore variation in the stable carbon (δ 13 C), nitrogen (δ 15 N), and oxygen (δ 18 O) isotope ratios of 288 plant samples identified as important to the three primate species from the Polonnaruwa Nature Sanctuary, Sri Lanka, relative to plant part, season, and canopy height. Our results show that plant part and height have the greatest effect on the δ 13 C and δ 18 O measurements of plants of immediate relevance to the primates, Macaca sinica, Semnopithecus priam thersites, and Trachypithecus vetulus, living in this monsoonal tropical forest. We find no influence of plant part, height or season on the δ 15 N of measured plants. While the plant part effect is particularly pronounced in δ 13 C between fruits and leaves, differential feeding height, and plant taxonomy influence plant δ 13 C and δ 18 O differences in addition to plant organ. Given that species composition in different regions and forest types will differ, the results urge caution in extrapolating general isotopic trends without substantial local baselines studies. © 2017 Wiley Periodicals, Inc.

  4. Evaluating ecohydrological theories of woody root distribution in the Kalahari.

    Directory of Open Access Journals (Sweden)

    Abinash Bhattachan

    Full Text Available The contribution of savannas to global carbon storage is poorly understood, in part due to lack of knowledge of the amount of belowground biomass. In these ecosystems, the coexistence of woody and herbaceous life forms is often explained on the basis of belowground interactions among roots. However, the distribution of root biomass in savannas has seldom been investigated, and the dependence of root biomass on rainfall regime remains unclear, particularly for woody plants. Here we investigate patterns of belowground woody biomass along a rainfall gradient in the Kalahari of southern Africa, a region with consistent sandy soils. We test the hypotheses that (1 the root depth increases with mean annual precipitation (root optimality and plant hydrotropism hypothesis, and (2 the root-to-shoot ratio increases with decreasing mean annual rainfall (functional equilibrium hypothesis. Both hypotheses have been previously assessed for herbaceous vegetation using global root data sets. Our data do not support these hypotheses for the case of woody plants in savannas. We find that in the Kalahari, the root profiles of woody plants do not become deeper with increasing mean annual precipitation, whereas the root-to-shoot ratios decrease along a gradient of increasing aridity.

  5. Building a Plant DNA Barcode Reference Library for a Diverse Tropical Flora: An Example from Queensland, Australia

    Directory of Open Access Journals (Sweden)

    Craig M. Costion

    2016-02-01

    Full Text Available A foundation for a DNA barcode reference library for the tropical plants of Australia is presented here. A total of 1572 DNA barcode sequences are compiled from 848 tropical Queensland species. The dataset represents 35% of the total flora of Queensland’s Wet Tropics Bioregion, 57% of its tree species and 28% of the shrub species. For approximately half of the sampled species, we investigated the occurrence of infraspecific molecular variation in DNA barcode loci rbcLa, matK, and the trnH-psbA intergenic spacer region across previously recognized biogeographic barriers. We found preliminary support for the notion that DNA barcode reference libraries can be used as a tool for inferring biogeographic patterns at regional scales. It is expected that this dataset will find applications in taxonomic, ecological, and applied conservation research.

  6. CMS: Estimated Deforested Area Biomass, Tropical America, Africa, and Asia, 2000

    Data.gov (United States)

    National Aeronautics and Space Administration — This data set provides estimates of pre-deforestation aboveground live woody biomass (AGLB) at 30-m resolution for deforested areas of tropical America, tropical...

  7. Plant litter dynamics in the forest-stream interface: precipitation is a major control across tropical biomes.

    Science.gov (United States)

    Tonin, Alan M; Gonçalves, José F; Bambi, Paulino; Couceiro, Sheyla R M; Feitoza, Lorrane A M; Fontana, Lucas E; Hamada, Neusa; Hepp, Luiz U; Lezan-Kowalczuk, Vânia G; Leite, Gustavo F M; Lemes-Silva, Aurea L; Lisboa, Leonardo K; Loureiro, Rafael C; Martins, Renato T; Medeiros, Adriana O; Morais, Paula B; Moretto, Yara; Oliveria, Patrícia C A; Pereira, Evelyn B; Ferreira, Lidiane P; Pérez, Javier; Petrucio, Mauricio M; Reis, Deusiano F; S Rezende, Renan; Roque, Nadia; Santos, Luiz E P; Siegloch, Ana E; Tonello, Gabriela; Boyero, Luz

    2017-09-07

    Riparian plant litter is a major energy source for forested streams across the world and its decomposition has repercussions on nutrient cycling, food webs and ecosystem functioning. However, we know little about plant litter dynamics in tropical streams, even though the tropics occupy 40% of the Earth's land surface. Here we investigated spatial and temporal (along a year cycle) patterns of litter inputs and storage in multiple streams of three tropical biomes in Brazil (Atlantic forest, Amazon forest and Cerrado savanna), predicting major differences among biomes in relation to temperature and precipitation regimes. Precipitation explained most of litter inputs and storage, which were generally higher in more humid biomes (litterfall: 384, 422 and 308 g m -2 y -1 , storage: 55, 113 and 38 g m -2 , on average in Atlantic forest, Amazon and Cerrado, respectively). Temporal dynamics varied across biomes in relation to precipitation and temperature, with uniform litter inputs but seasonal storage in Atlantic forest streams, seasonal inputs in Amazon and Cerrado streams, and aseasonal storage in Amazon streams. Our findings suggest that litter dynamics vary greatly within the tropics, but point to the major role of precipitation, which contrasts with the main influence of temperature in temperate areas.

  8. Backwater development by woody debris

    Science.gov (United States)

    Geertsema, Tjitske; Torfs, Paul; Teuling, Ryan; Hoitink, Ton

    2017-04-01

    Placement of woody debris is a common method for increasing ecological values in river and stream restoration, and is thus widely used in natural environments. Water managers, however, are afraid to introduce wood in channels draining agricultural and urban areas. Upstream, it may create backwater, depending on hydrodynamic characteristics including the obstruction ratio, the Froude number and the surface level gradient. Patches of wood may trigger or counter morphological activity, both laterally, through bank erosion and protection, and vertically, with pool and riffle formation. Also, a permeable construction composed of wood will weather over time. Both morphodynamic activity and weathering cause backwater effects to change in time. The purpose of this study is to quantify the time development of backwater effects caused by woody debris. Hourly water levels gauged upstream and downstream of patches and discharge are collected for five streams in the Netherlands. The water level drop over the woody debris patch relates to discharge in the streams. This relation is characterized by an increasing water level difference for an increasing discharge, up to a maximum. If the discharge increases beyond this level, the water level difference reduces to the value that may represent the situation without woody debris. This reduction depends primarily on the obstruction ratio of the woody debris in the channel cross-section. Morphologic adjustments in the stream and reorientation of the woody material reduce the water level drop over the patches in time. Our results demonstrate that backwater effects can be reduced by optimizing the location where woody debris is placed and manipulating the obstruction ratio. Current efforts are focussed on representing woody debris in a one-dimensional numerical model, aiming to obtain a generic tool to achieve a stream design with woody debris that minimizes backwater.

  9. Earthworms and Plant Residues Modify Nematodes in Tropical Cropping Soils (Madagascar: A Mesocosm Experiment

    Directory of Open Access Journals (Sweden)

    Cécile Villenave

    2010-01-01

    Full Text Available Free-living nematodes present several characteristics that have led to their use as bioindicators of soil quality. Analyzing the structure of nematofauna is a pertinent way to understand soil biological processes. Earthworms play an important role in soil biological functioning and organic matter dynamics. Their effects on soil nematofauna have seldom been studied. We studied the effect of the tropical endogeic earthworm, Pontoscolex corethrurus, on nematode community structure in a 5-month field mesocosm experiment conducted in Madagascar. Ten different treatments with or without earthworms and with or without organic residues (rice, soybean were compared. Organic residues were applied on the soil surface or mixed with the soil. The abundance of nematodes (bacterial and fungal feeders was higher in presence of P. corethrurus than in their absence. The type of plant residues as well as their localisation had significant effects on the abundance and composition of soil nematodes. The analysis of nematode community structure showed that earthworm activity led to an overall activation of the microbial compartment without specific stimulation of the bacterial or fungal compartment.

  10. Earthworms and Plant Residues Modify Nematodes in Tropical Cropping Soils (Madagascar): A Mesocosm Experiment

    International Nuclear Information System (INIS)

    Villenave, C.; Kichenin, E.; Djigal, D.; Blanchart, E.; Rabary, B.; Djigal, D.

    2010-01-01

    Free-living nematodes present several characteristics that have led to their use as bio indicators of soil quality. Analyzing the structure of nematofauna is a pertinent way to understand soil biological processes. Earthworms play an important role in soil biological functioning and organic matter dynamics. Their effects on soil nematofauna have seldom been studied. We studied the effect of the tropical endogeic earthworm, Pontoscolex corethrurus, on nematode community structure in a 5-month field mesocosm experiment conducted in Madagascar. Ten different treatments with or without earthworms and with or without organic residues (rice, soybean) were compared. Organic residues were applied on the soil surface or mixed with the soil. The abundance of nematodes (bacterial and fungal feeders) was higher in presence of P. corethrurus than in their absence. The type of plant residues as well as their localisation had significant effects on the abundance and composition of soil nematodes. The analysis of nematode community structure showed that earthworm activity led to an overall activation of the microbial compartment without specific stimulation of the bacterial or fungal compartment.

  11. Assessing woody vegetation trends in Sahelian drylands using MODIS based seasonal metrics

    DEFF Research Database (Denmark)

    Brandt, Martin Stefan; Hiernaux, Pierre; Rasmussen, Kjeld

    2016-01-01

    Woody plants play a major role for the resilience of drylands and in peoples' livelihoods. However, due to their scattered distribution, quantifying and monitoring woody cover over space and time is challenging. We develop a phenology driven model and train/validate MODIS (MCD43A4, 500 m) derived...

  12. Processing woody debris biomass for co-milling with pulverized coal

    Science.gov (United States)

    Dana Mitchell; Bob Rummer

    2007-01-01

    The USDA, Forest Service, Forest Products Lab funds several grants each year for the purpose of studying woody biomass utilization. One selected project proposed removing small diameter stems and unmerchantable woody material from National Forest lands and delivering it to a coal-fired power plant in Alabama for energy conversion. The Alabama Power Company...

  13. Study Of Plant Regeneration Potential In Tropical Moist Deciduous Forest In Northern India

    Directory of Open Access Journals (Sweden)

    Ashish K Mishra

    2013-12-01

    Full Text Available Regeneration patterns of species population can address climate change by adaptive evolution or by migrating association to survive in their favorable climate and finally decided to particular forest future. In this paper we examined the status of regeneration potential of tree species in tropical moist deciduous forest at Katerniaghat Wildlife Sanctuary, Northern India. To investigate tree, sapling and seedling population distribution, we examine regeneration status in 145 random plots in study area. Total 74 plant species of 60 genera belonging to 32 families out of which 71 species of trees, 56 of seedlings and 60 of saplings were found in the forest. On the basis of importance value index Mallotus philippensis, Tectona grandis, Shorea robusta, Syzygium cumini and Bombax ceiba have been found as dominant species in the study area. As far as the regeneration status is concerned, the maximum tree species (64% have been found in good regeneration category. Significant variations in species richness and population density, between three life form (i. e. tree, sapling and seedling have been found. In which only three new tree species Prosopis juliflora, Psidium guajava and Morus alba were added in sapling and seedling stage. It is major ecological concern that about 19 % economically important plant species like Madhuca longifolia, Terminalia elliptica, Buchanania cochinchinensis, some Ficus species etc. have been found in poor regeneration phage, whereas about 7% species found in no regeneration categories. International Journal of Environment, Volume-2, Issue-1, Sep-Nov 2013, Pages 153-163 DOI: http://dx.doi.org/10.3126/ije.v2i1.9218

  14. Potential link between plant and fungal distributions in a dipterocarp rainforest: community and phylogenetic structure of tropical ectomycorrhizal fungi across a plant and soil ecotone.

    Science.gov (United States)

    Peay, Kabir G; Kennedy, Peter G; Davies, Stuart J; Tan, Sylvester; Bruns, Thomas D

    2010-01-01

    *Relatively little is known about diversity or structure of tropical ectomycorrhizal communities or their roles in tropical ecosystem dynamics. In this study, we present one of the largest molecular studies to date of an ectomycorrhizal community in lowland dipterocarp rainforest. *We sampled roots from two 0.4 ha sites located across an ecotone within a 52 ha forest dynamics plot. Our plots contained > 500 tree species and > 40 species of ectomycorrhizal host plants. Fungi were identified by sequencing ribosomal RNA genes. *The community was dominated by the Russulales (30 species), Boletales (17), Agaricales (18), Thelephorales (13) and Cantharellales (12). Total species richness appeared comparable to molecular studies of temperate forests. Community structure changed across the ecotone, although it was not possible to separate the role of environmental factors vs host plant preferences. Phylogenetic analyses were consistent with a model of community assembly where habitat associations are influenced by evolutionary conservatism of functional traits within ectomycorrhizal lineages. *Because changes in the ectomycorrhizal fungal community parallel those of the tree community at this site, this study demonstrates the potential link between the distribution of tropical tree diversity and the distribution of tropical ectomycorrhizal diversity in relation to local-scale edaphic variation.

  15. Physiological mechanisms of drought-induced tree die-off in relation to carbon, hydraulic and respiratory stress in a drought-tolerant woody plant.

    Science.gov (United States)

    Saiki, Shin-Taro; Ishida, Atsushi; Yoshimura, Kenichi; Yazaki, Kenichi

    2017-06-07

    Drought-induced tree die-off related to climate change is occurring worldwide and affects the carbon stocks and biodiversity in forest ecosystems. Hydraulic failure and carbon starvation are two commonly proposed mechanisms for drought-induced tree die-off. Here, we show that inhibited branchlet respiration and soil-to-leaf hydraulic conductance, likely caused by cell damage, occur prior to hydraulic failure (xylem embolism) and carbon starvation (exhaustion of stored carbon in sapwood) in a drought-tolerant woody species, Rhaphiolepis wrightiana Maxim. The ratio of the total leaf area to the twig sap area was used as a health indicator after drought damage. Six adult trees with different levels of tree health and one dead adult tree were selected. Two individuals having the worst and second worst health among the six live trees died three months after our study was conducted. Soil-to-leaf hydraulic conductance and leaf gas exchange rates decreased linearly as tree health declined, whereas xylem cavitation and total non-structural carbon remained unchanged in the branchlets except in the dead and most unhealthy trees. Respiration rates and the number of living cells in the sapwood decreased linearly as tree health declined. This study is the first report on the importance of dehydration tolerance and respiration maintenance in living cells.

  16. Light interception efficiency explained by two simple variables: a test using a diversity of small- to medium-sized woody plants

    NARCIS (Netherlands)

    Duursma, R.A.; Falster, D.S.; Valladares, F.; Sterck, F.J.; Pearcy, R.W.; Lusk, C.; Sendall, K.M.; Nordenstahl, M.; Houter, N.C.; Atwell, B.J.; Kelly, N.; Kelly, J.W.G.; Liberloo, M.; Tissue, D.T.; Medlyn, B.E.; Ellsworth, D.S.

    2012-01-01

    Plant light interception efficiency is a crucial determinant of carbon uptake by individual plants and by vegetation. Our aim was to identify whole-plant variables that summarize complex crown architecture, which can be used to predict light interception efficiency. •We gathered the largest database

  17. CARBON SEQUESTRATION AND PLANT COMMUNITY DYNAMICS FOLLOWING REFORESTATION OF TROPICAL PASTURE.

    Science.gov (United States)

    WHENDEE L. SILVER; LARA M. KUEPPERS; ARIEL E. LUGO; REBECCA OSTERTAG; VIRGINIA MATZEK

    2004-01-01

    Conversion of abandoned cattle pastures to secondary forests and plantations in the tropics has been proposed as a means to increase rates of carbon (C) sequestration from the atmosphere and enhance local biodiversity. We used a long-term tropical reforestation project (55–61 yr) to estimate rates of above- and belowground C sequestration and to investigate the impact...

  18. Pilot-Plant for Energy Recovery from Tropical Waste Food Materials ...

    African Journals Online (AJOL)

    An experimental unit for obtaining gaseous methane from waste food materials is discussed and results are presented for experimental tests with animal wastes and tropical waste food materials. The tropical waste food considered include garri, boiled beans and plantains. As expected, the animal wastes produced higher ...

  19. Diversity in plant hydraulic traits explains seasonal and inter-annual variations of vegetation dynamics in seasonally dry tropical forests.

    Science.gov (United States)

    Xu, Xiangtao; Medvigy, David; Powers, Jennifer S; Becknell, Justin M; Guan, Kaiyu

    2016-10-01

    We assessed whether diversity in plant hydraulic traits can explain the observed diversity in plant responses to water stress in seasonally dry tropical forests (SDTFs). The Ecosystem Demography model 2 (ED2) was updated with a trait-driven mechanistic plant hydraulic module, as well as novel drought-phenology and plant water stress schemes. Four plant functional types were parameterized on the basis of meta-analysis of plant hydraulic traits. Simulations from both the original and the updated ED2 were evaluated against 5 yr of field data from a Costa Rican SDTF site and remote-sensing data over Central America. The updated model generated realistic plant hydraulic dynamics, such as leaf water potential and stem sap flow. Compared with the original ED2, predictions from our novel trait-driven model matched better with observed growth, phenology and their variations among functional groups. Most notably, the original ED2 produced unrealistically small leaf area index (LAI) and underestimated cumulative leaf litter. Both of these biases were corrected by the updated model. The updated model was also better able to simulate spatial patterns of LAI dynamics in Central America. Plant hydraulic traits are intercorrelated in SDTFs. Mechanistic incorporation of plant hydraulic traits is necessary for the simulation of spatiotemporal patterns of vegetation dynamics in SDTFs in vegetation models. © 2016 The Authors. New Phytologist © 2016 New Phytologist Trust.

  20. Global diversification of a tropical plant growth form: environmental correlates and historical contingencies in climbing palms.

    Science.gov (United States)

    Couvreur, Thomas L P; Kissling, W Daniel; Condamine, Fabien L; Svenning, Jens-Christian; Rowe, Nick P; Baker, William J

    2014-01-01

    Tropical rain forests (TRF) are the most diverse terrestrial biome on Earth, but the diversification dynamics of their constituent growth forms remain largely unexplored. Climbing plants contribute significantly to species diversity and ecosystem processes in TRF. We investigate the broad-scale patterns and drivers of species richness as well as the diversification history of climbing and non-climbing palms (Arecaceae). We quantify to what extent macroecological diversity patterns are related to contemporary climate, forest canopy height, and paleoclimatic changes. We test whether diversification rates are higher for climbing than non-climbing palms and estimate the origin of the climbing habit. Climbers account for 22% of global palm species diversity, mostly concentrated in Southeast Asia. Global variation in climbing palm species richness can be partly explained by past and present-day climate and rain forest canopy height, but regional differences in residual species richness after accounting for current and past differences in environment suggest a strong role of historical contingencies in climbing palm diversification. Climbing palms show a higher net diversification rate than non-climbers. Diversification analyses of palms detected a diversification rate increase along the branches leading to the most species-rich clade of climbers. Ancestral character reconstructions revealed that the climbing habit originated between early Eocene and Miocene. These results imply that changes from non-climbing to climbing habits may have played an important role in palm diversification, resulting in the origin of one fifth of all palm species. We suggest that, in addition to current climate and paleoclimatic changes after the late Neogene, present-day diversity of climbing palms can be explained by morpho-anatomical innovations, the biogeographic history of Southeast Asia, and/or ecological opportunities due to the diversification of high-stature dipterocarps in Asian TRFs.

  1. Response of loblolly pine to complete woody and herbaceous control: projected yields and economic outcomes - the COMProject

    Science.gov (United States)

    James H. Miller; R.L. Busby; B.R. Zutter; S.M. Zedaker; M.B. Edwards; R.A. Newbold

    1995-01-01

    Abstract.Age-8 and -9 data from the 13 study plantations of the Competition Omission Monitoring Project (COMP) were used to project yields and derive economic outcomes for loblolly pine (Pinus taeda L.). COMP treatments were chop-burn, complete woody plant control, complete herbaceous plant control for 4 years, and complete woody...

  2. Ecology of Land Cover Change in Glaciated Tropical Mountains

    Directory of Open Access Journals (Sweden)

    Kenneth R. Young

    2014-12-01

    Full Text Available Tropical mountains contain unique biological diversity, and are subject to many consequences of global climate change, exasperated by concurrent socioeconomic shifts. Glaciers are in a negative mass balance, exposing substrates to primary succession and altering downslope wetlands and streams. A review of recent trends and future predictions suggests a likely reduction in areas of open habitat for species of high mountains due to greater woody plant cover, accompanied by land use shifts by farmers and pastoralists along the environmental gradients of tropical mountains. Research is needed on the biodiversity and ecosystem consequences of successional change, including the direct effects of retreating glaciers and the indirect consequences of combined social and ecological drivers in lower elevations. Areas in the high mountains that are protected for nature conservation or managed collectively by local communities represent opportunities for integrated research and development approaches that may provide ecological spaces for future species range shifts.

  3. SNAG AND LARGE WOODY DEBRIS DYNAMICS IN RIPARIAN FORESTS

    Science.gov (United States)

    Important components of riparian forests are snags and streamside large woody debris (LWD) because they are functional in maintaining water quality and providing habitat for numerous plants and animals. To effectively manage riparian forests, it is important to understand the dy...

  4. Assessment of Soil Seedbank Composition of Woody Species in ...

    African Journals Online (AJOL)

    Bheema

    Momona Ethiopian Journal of Science (MEJS), V6(1):25-44,2014. ©CNCS ... In present work, soil seedbank assessment of woody plant species was made in .... 1995; Azene Bekele, 2007) and NDA (Natural Database for Africa) software. 2.3.

  5. The Multiple Impacts of Tropical Forest Fragmentation on Arthropod Biodiversity and on their Patterns of Interactions with Host Plants

    Science.gov (United States)

    Benítez-Malvido, Julieta; Dáttilo, Wesley; Martínez-Falcón, Ana Paola; Durán-Barrón, César; Valenzuela, Jorge; López, Sara; Lombera, Rafael

    2016-01-01

    Tropical rain forest fragmentation affects biotic interactions in distinct ways. Little is known, however, about how fragmentation affects animal trophic guilds and their patterns of interactions with host plants. In this study, we analyzed changes in biotic interactions in forest fragments by using a multitrophic approach. For this, we classified arthropods associated with Heliconia aurantiaca herbs into broad trophic guilds (omnivores, herbivores and predators) and assessed the topological structure of intrapopulation plant-arthropod networks in fragments and continuous forests. Habitat type influenced arthropod species abundance, diversity and composition with greater abundance in fragments but greater diversity in continuous forest. According to trophic guilds, coleopteran herbivores were more abundant in continuous forest and overall omnivores in fragments. Continuous forest showed a greater diversity of interactions than fragments. Only in fragments, however, did the arthropod community associated with H aurantiaca show a nested structure, suggesting novel and/or opportunistic host-arthropod associations. Plants, omnivores and predators contributed more to nestedness than herbivores. Therefore, Heliconia-arthropod network properties do not appear to be maintained in fragments mainly caused by the decrease of herbivores. Our study contributes to the understanding of the impact of fragmentation on the structure and dynamics of multitrophic arthropod communities associated with a particular plant species of the highly biodiverse tropical forests. Nevertheless, further replication of study sites is needed to strengthen the conclusion that forest fragmentation negatively affects arthropod assemblages. PMID:26731271

  6. The Multiple Impacts of Tropical Forest Fragmentation on Arthropod Biodiversity and on their Patterns of Interactions with Host Plants.

    Science.gov (United States)

    Benítez-Malvido, Julieta; Dáttilo, Wesley; Martínez-Falcón, Ana Paola; Durán-Barrón, César; Valenzuela, Jorge; López, Sara; Lombera, Rafael

    2016-01-01

    Tropical rain forest fragmentation affects biotic interactions in distinct ways. Little is known, however, about how fragmentation affects animal trophic guilds and their patterns of interactions with host plants. In this study, we analyzed changes in biotic interactions in forest fragments by using a multitrophic approach. For this, we classified arthropods associated with Heliconia aurantiaca herbs into broad trophic guilds (omnivores, herbivores and predators) and assessed the topological structure of intrapopulation plant-arthropod networks in fragments and continuous forests. Habitat type influenced arthropod species abundance, diversity and composition with greater abundance in fragments but greater diversity in continuous forest. According to trophic guilds, coleopteran herbivores were more abundant in continuous forest and overall omnivores in fragments. Continuous forest showed a greater diversity of interactions than fragments. Only in fragments, however, did the arthropod community associated with H aurantiaca show a nested structure, suggesting novel and/or opportunistic host-arthropod associations. Plants, omnivores and predators contributed more to nestedness than herbivores. Therefore, Heliconia-arthropod network properties do not appear to be maintained in fragments mainly caused by the decrease of herbivores. Our study contributes to the understanding of the impact of fragmentation on the structure and dynamics of multitrophic arthropod communities associated with a particular plant species of the highly biodiverse tropical forests. Nevertheless, further replication of study sites is needed to strengthen the conclusion that forest fragmentation negatively affects arthropod assemblages.

  7. Plant Traits Demonstrate That Temperate and Tropical Giant Eucalypt Forests Are Ecologically Convergent with Rainforest Not Savanna

    Science.gov (United States)

    Tng, David Y. P.; Jordan, Greg J.; Bowman, David M. J. S.

    2013-01-01

    Ecological theory differentiates rainforest and open vegetation in many regions as functionally divergent alternative stable states with transitional (ecotonal) vegetation between the two forming transient unstable states. This transitional vegetation is of considerable significance, not only as a test case for theories of vegetation dynamics, but also because this type of vegetation is of major economic importance, and is home to a suite of species of conservation significance, including the world’s tallest flowering plants. We therefore created predictions of patterns in plant functional traits that would test the alternative stable states model of these systems. We measured functional traits of 128 trees and shrubs across tropical and temperate rainforest – open vegetation transitions in Australia, with giant eucalypt forests situated between these vegetation types. We analysed a set of functional traits: leaf carbon isotopes, leaf area, leaf mass per area, leaf slenderness, wood density, maximum height and bark thickness, using univariate and multivariate methods. For most traits, giant eucalypt forest was similar to rainforest, while rainforest, particularly tropical rainforest, was significantly different from the open vegetation. In multivariate analyses, tropical and temperate rainforest diverged functionally, and both segregated from open vegetation. Furthermore, the giant eucalypt forests overlapped in function with their respective rainforests. The two types of giant eucalypt forests also exhibited greater overall functional similarity to each other than to any of the open vegetation types. We conclude that tropical and temperate giant eucalypt forests are ecologically and functionally convergent. The lack of clear functional differentiation from rainforest suggests that giant eucalypt forests are unstable states within the basin of attraction of rainforest. Our results have important implications for giant eucalypt forest management. PMID:24358359

  8. Woody biomass phytoremediation of contaminated brownfield land

    Energy Technology Data Exchange (ETDEWEB)

    French, Christopher J. [School of Biological and Earth Sciences, Liverpool John Moores University, Byrom Street, Liverpool L3 3AF (United Kingdom); Dickinson, Nicholas M. [School of Biological and Earth Sciences, Liverpool John Moores University, Byrom Street, Liverpool L3 3AF (United Kingdom)]. E-mail: n.m.dickinson@livjm.ac.uk; Putwain, Philip D. [Ecological Restoration Consultants (ERC), Ness Botanic Gardens, University of Liverpool, Ness, Cheshire CH64 (United Kingdom)

    2006-06-15

    Economic and environmental regeneration of post-industrial landscapes frequently involves some element of re-afforestation or tree planting. We report field trials that evaluate whether woody biomass production is compatible with managing residual trace element contamination in brownfield soils. Large-scale mapping of contamination showed a heterogenous dispersion of metals and arsenic, and highly localised within-site hotspots. Yields of Salix, Populus and Alnus were economically viable, showing that short-rotation coppice has a potentially valuable role in community forestry. Mass balance modelling demonstrated that phytoextraction potentially could reduce contamination hotspots of more mobile elements (Cd and Zn) within a 25-30-year life cycle of the crops. Cd and Zn in stems and foliage of Salix were 4-13 times higher than EDTA-extractable soil concentrations. Lability of other trace elements (As, Pb, Cu, Ni) was not increased 3 years after planting the coppice; woody biomass may provide an effective reduction of exposure (phytostabilisation) to these less mobile contaminants. - Field trials show short-rotation coppice provides effective risk management and remediation solutions to hotspots of residual metal and As contamination of brownfield land.

  9. Woody biomass phytoremediation of contaminated brownfield land

    International Nuclear Information System (INIS)

    French, Christopher J.; Dickinson, Nicholas M.; Putwain, Philip D.

    2006-01-01

    Economic and environmental regeneration of post-industrial landscapes frequently involves some element of re-afforestation or tree planting. We report field trials that evaluate whether woody biomass production is compatible with managing residual trace element contamination in brownfield soils. Large-scale mapping of contamination showed a heterogenous dispersion of metals and arsenic, and highly localised within-site hotspots. Yields of Salix, Populus and Alnus were economically viable, showing that short-rotation coppice has a potentially valuable role in community forestry. Mass balance modelling demonstrated that phytoextraction potentially could reduce contamination hotspots of more mobile elements (Cd and Zn) within a 25-30-year life cycle of the crops. Cd and Zn in stems and foliage of Salix were 4-13 times higher than EDTA-extractable soil concentrations. Lability of other trace elements (As, Pb, Cu, Ni) was not increased 3 years after planting the coppice; woody biomass may provide an effective reduction of exposure (phytostabilisation) to these less mobile contaminants. - Field trials show short-rotation coppice provides effective risk management and remediation solutions to hotspots of residual metal and As contamination of brownfield land

  10. Trees, Shrubs, and Woody Vines of the Bluff Experimental Forest, Warren County, Mississippi

    Science.gov (United States)

    Robert L. Johnson; Elbert L. Little

    1967-01-01

    Nearly 100 species of trees, shrubs, and woody vines grow naturally on the 450-acre Bluff Experimental Forest in west-central Mississippi. This publication lists the plants and provides information on silvical characteristics of the tree species.

  11. The Species Richness of Vascular Plants and Amphibia in Major Plant Communities in Temperate to Tropical Australia: Relationship with Annual Biomass Production

    International Nuclear Information System (INIS)

    Specht, R. L.; Tyler, M.J.

    2010-01-01

    Aerodynamic fluxes (frictional, thermal, evaporative) in the atmosphere as it flows over and through a plant community determine the Foliage Projective Covers and eco-morphological attributes of new leaves developed annually in overstorey and understorey strata. The number of leaves produced on vertical foliage shoots depends on available soil water and nutrients, also ambient temperature, during this short growth season. Stem density (number of stems per hectare) and species richness (number of species per hectare) in the overstorey of major Floristic Groups are correlated with annual shoot growth (ASG, t ha-1) in that stratum. Species richness in the overstorey increases in the climatic gradient from the arid to the humid zone as well as with increasing air temperatures (about 10 degree C) from temperate to tropical Australia. Species richness in the understorey is highest in plant communities in temperate Australia, decreasing in the temperature gradient towards the tropics. As with other major plant and animal groups within an ecosystem, the species richness of Amphibia is correlated with the amount of solar energy fixed (per annum) by the major plant formation in the regional photosynthetic potential determined by the foliage shoots (ASG, t ha-1) produced annually in the overstorey.

  12. The Species Richness of Vascular Plants and Amphibia in Major Plant Communities in Temperate to Tropical Australia: Relationship with Annual Biomass Production

    Directory of Open Access Journals (Sweden)

    R. L. Specht

    2010-01-01

    Full Text Available Aerodynamic fluxes (frictional, thermal, evaporative in the atmosphere as it flows over and through a plant community determine the Foliage Projective Covers and eco-morphological attributes of new leaves developed annually in overstorey and understorey strata. The number of leaves produced on vertical foliage shoots depends on available soil water and nutrients, also ambient temperature, during this short growth season. Stem density (number of stems per hectare and species richness (number of species per hectare in the overstorey of major Floristic Groups are correlated with annual shoot growth (ASG, t ha−1 in that stratum. Species richness in the overstorey increases in the climatic gradient from the arid to the humid zone as well as with increasing air temperatures (about 10oC from temperate to tropical Australia. Species richness in the understorey is highest in plant communities in temperate Australia, decreasing in the temperature gradient towards the tropics. As with other major plant and animal groups within an ecosystem, the species richness of Amphibia is correlated with the amount of solar energy fixed (per annum by the major plant formation in the region—a photosynthetic potential determined by the foliage shoots (ASG, t ha−1 produced annually in the overstorey.

  13. Effects of experimental nitrogen additions on plant diversity in tropical forests of contrasting disturbance regimes in southern China

    International Nuclear Information System (INIS)

    Lu Xiankai; Mo Jiangming; Gilliam, Frank S.; Yu Guirui; Zhang Wei; Fang Yunting; Huang Juan

    2011-01-01

    Responses of understory plant diversity to nitrogen (N) additions were investigated in reforested forests of contrasting disturbance regimes in southern China from 2003 to 2008: disturbed forest (with harvesting of understory vegetation and litter) and rehabilitated forest (without harvesting). Experimental additions of N were administered as the following treatments: Control, 50 kg N ha -1 yr -1 , and 100 kg N ha -1 yr -1 . Nitrogen additions did not significantly affect understory plant richness, density, and cover in the disturbed forest. Similarly, no significant response was found for canopy closure in this forest. In the rehabilitated forest, species richness and density showed no significant response to N additions; however, understory cover decreased significantly in the N-treated plots, largely a function of a significant increase in canopy closure. Our results suggest that responses of plant diversity to N deposition may vary with different land-use history, and rehabilitated forests may be more sensitive to N deposition. - Highlights: → Nitrogen addition had no significant effect on understory plant diversity in the disturbed forest. → Nitrogen addition significantly decreased understory plant cover. → Nitrogen addition had no effect on richness and density in the rehabilitated forest. → The decrease is largely a function of a significant increase in canopy closure. → Land-use practices may dominate the responses of plant diversity to N addition. - Research in disturbed forests of southeastern China demonstrates that land-use history can substantially alter effects of excess nitrogen deposition on plant diversity of tropical forest ecosystems.

  14. Coarse woody debris in undisturbed and logged forests in the eastern Brazilian Amazon.

    Science.gov (United States)

    Michael Keller; Michael Palace; Gregory P. Asner; Rodrigo Jr. Pereira; Jose Natalino M. Silva

    2004-01-01

    Coarse woody debris (CWD) is an important component of the carbon cycle in tropical forests. We measured the volume and density of fallen CWD at two sites, Cauaxi and Tapajós in the Eastern Amazon. At both sites we studied undisturbed forests (UFs) and logged forests 1 year after harvest. Conventional logging (CL) and reduced impact logging (RIL) were...

  15. 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.

  16. A sustainable woody biomass biorefinery.

    Science.gov (United States)

    Liu, Shijie; Lu, Houfang; Hu, Ruofei; Shupe, Alan; Lin, Lu; Liang, Bin

    2012-01-01

    Woody biomass is renewable only if sustainable production is imposed. An optimum and sustainable biomass stand production rate is found to be one with the incremental growth rate at harvest equal to the average overall growth rate. Utilization of woody biomass leads to a sustainable economy. Woody biomass is comprised of at least four components: extractives, hemicellulose, lignin and cellulose. While extractives and hemicellulose are least resistant to chemical and thermal degradation, cellulose is most resistant to chemical, thermal, and biological attack. The difference or heterogeneity in reactivity leads to the recalcitrance of woody biomass at conversion. A selection of processes is presented together as a biorefinery based on incremental sequential deconstruction, fractionation/conversion of woody biomass to achieve efficient separation of major components. A preference is given to a biorefinery absent of pretreatment and detoxification process that produce waste byproducts. While numerous biorefinery approaches are known, a focused review on the integrated studies of water-based biorefinery processes is presented. Hot-water extraction is the first process step to extract value from woody biomass while improving the quality of the remaining solid material. This first step removes extractives and hemicellulose fractions from woody biomass. While extractives and hemicellulose are largely removed in the extraction liquor, cellulose and lignin largely remain in the residual woody structure. Xylo-oligomers, aromatics and acetic acid in the hardwood extract are the major components having the greatest potential value for development. Higher temperature and longer residence time lead to higher mass removal. While high temperature (>200°C) can lead to nearly total dissolution, the amount of sugars present in the extraction liquor decreases rapidly with temperature. Dilute acid hydrolysis of concentrated wood extracts renders the wood extract with monomeric sugars

  17. Studies on cambial activity: advances and challenges in the knowledge of growth dynamics of Brazilian woody species

    Directory of Open Access Journals (Sweden)

    CÁTIA H. CALLADO

    2014-03-01

    Full Text Available The lack of specific research on the sequence of events that determine plant growth from meristem until wood formation represents a gap in the knowledge of growth dynamics in woody species. In this work, we surveyed published studies concerning cambial activity of Brazilian native species aiming at allowing the comparison of applied methods and obtained results. The annual cambial seasonality was observed in all the investigated species. Nevertheless, we found high heterogeneity in the used methodologies. As a result from this analysis, our opinion points to the need for standardizing sampling protocols and for discussing the suitability of experimental designs. This will help to define with greater precision the factors that determine the radial growth in the different tropical ecosystems.

  18. 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

  19. Climatological determinants of woody cover in Africa

    OpenAIRE

    Good, Stephen P.; Caylor, Kelly K.

    2011-01-01

    Determining the factors that influence the distribution of woody vegetation cover and resolving the sensitivity of woody vegetation cover to shifts in environmental forcing are critical steps necessary to predict continental-scale responses of dryland ecosystems to climate change. We use a 6-year satellite data record of fractional woody vegetation cover and an 11-year daily precipitation record to investigate the climatological controls on woody vegetation cover across the African continent....

  20. Woody encroachment impacts on ecosystem nitrogen cycling: fixation, storage and gas loss

    Science.gov (United States)

    Soper, F.; Sparks, J. P.

    2016-12-01

    Woody encroachment is a pervasive land cover change throughout the tropics and subtropics. Encroachment is frequently catalyzed by nitrogen (N)-fixing trees and the resulting N inputs have the potential to alter whole-ecosystem N cycling, accumulation and loss. In the southern US, widespread encroachment by legume Prosopis glandulosa is associated with increased soil total N storage, inorganic N concentrations, and net mineralization and nitrification rates. To better understand the effects of this process on ecosystem N cycling, we investigated patterns of symbiotic N fixation, N accrual and soil N trace gas and N2 emissions during Prosopis encroachment into the southern Rio Grande Plains. Analyses of d15N in foliage, xylem sap and plant-available soil N suggested that N fixation rates vary seasonally, inter-annually and as a function of plant age and abiotic conditions. Applying a small-scale mass balance model to soil N accrual around individual trees (accounting for atmospheric inputs, and gas and hydrologic losses) generated current fixation estimates of 11 kg N ha-1 yr-1, making symbiotic fixation the largest input of N to the ecosystem. However, soil N accrual and increased cycling rates did not translate into increased N gas losses. Two years of field measurements of a complete suite of N trace gases (ammonia, nitrous oxide, nitric oxide and other oxidized N compounds) found no difference in flux between upland Prosopis groves and adjacent unencroached grasslands. Total emissions average 0.56-0.65 kg N ha-1 yr-1, comparable to other southern US grasslands. Lab incubations suggested that N2 losses are likely to be low, with field oxygen conditions not usually conducive to denitrification. Taken together, results suggest that this ecosystem is currently experiencing a period of significant net N accrual, driven by fixation under ongoing encroachment. Given the large scale of woody legume encroachment in the USA, this process is likely to contribute

  1. Ozone air pollution effects on tree-ring growth,{delta}{sup 13}C, visible foliar injury and leaf gas exchange in three ozone-sensitive woody plant species

    Energy Technology Data Exchange (ETDEWEB)

    Novak, K. [Swiss Federal Inst. for Forest, Snow and Landscape Research, Birmensdorf (Switzerland); Agroscope FAL Reckenholz, Swiss Federal Research Station for Agroecology and Agriculture, Zurich (Switzerland); Saurer, M. [Paul Scherrer Inst. Villigen (Switzerland); Fuhrer, J. [Agroscope FAL Reckenholz, Swiss Federal Research Station for Agroecology and Agriculture, Zurich (Switzerland); Skelly, J.M. [Pennsylvania State Univ., University Park, PA (United States). Dept. of Plant Pathology; Krauchi, N.; Schaub, M. [Swiss Federal Inst. for Forest, Snow and Landscape Research, Birmensdorf (Switzerland)

    2007-07-15

    Species specific plant responses to tropospheric ozone pollution depend on a range of morphological, biochemical and physiological characteristics as well as environmental factors. The effects of ambient tropospheric ozone on annual tree-ring growth, {delta}{sup 13} C in the rings, leaf gas exchange and ozone-induced visible foliar injury in three ozone-sensitive woody plant species in southern Switzerland were assessed during the 2001 and 2002 growing seasons. Seedlings of Populus nigra L., Viburnum lantana L. and Fraxinus excelsior L. were exposed to charcoal-filtered air and non-filtered air in open-top chambers, and to ambient air (AA) in open plots. The objective was to determine if a relationship exists between measurable ozone-induced effects at the leaf level and subsequent changes in annual tree-ring growth and {delta} {sup 13} C signatures. The visible foliar injury, early leaf senescence and premature leaf loss in all species was attributed to the ambient ozone exposures in the region. Ozone had pronounced negative effects on net photosynthesis and stomatal conductance in all species in 2002 and in V. lantana and F. excelsior in 2001. Water-use efficiency decreased and intercellular carbon dioxide concentrations increased in all species in response to ozone in 2002 only. The width and {delta}{sup 13} C of the 2001 and 2002 growth rings were measured for all species at the end of the 2002 growing season. Significant ozone-induced effects at the leaf level did not correspond to reduced tree-ring growth or increased {delta}{sup 13} C in all species, suggesting that the timing of ozone exposure and extent of leaf-level responses may be relevant in determining the sensitivity of tree productivity to ozone exposure. 48 refs., 4 tabs., 2 figs.

  2. Anthelmintic efficacy of five tropical native Australian plants against Haemonchus contortus and Trichostrongylus colubriformis in experimentally infected goats (Capra hircus).

    Science.gov (United States)

    Moreno, F C; Gordon, I J; Knox, M R; Summer, P M; Skerrat, L F; Benvenutti, M A; Saumell, C A

    2012-06-08

    The study of the anthelmintic properties of plants rich in plant secondary metabolites can provide ecologically sound methods for the treatment of parasites on grazing animals. The purpose of the present study was to evaluate the anthelmintic effect of five tropical native Australian plant species rich in plant secondary metabolites on adult Haemonchus contortus and Trichostrongylus colubriformis in experimentally infected goats. Thirty young, nematode-free goats were infected with 2500 H. contortus and 5000 T. colubriformis infective larvae thrice weekly for a week (day 1-7 of the experiment). On day 27 after first infection, the goats were allocated into six groups of five animals per group. From day 28 to day 35, fresh leaves from Acacia salicina, Acacia nilotica, Eucalyptus corymbia, Casuarina cunninghamiana and Eucalyptus drepanophylla were included in the goats diet. Five groups were offered leaves from one of these plant species and one group, the untreated control, received only the basal diet formulated with 20% Medicago sativa and 80% Avena sativa. Following plant material administration, the goats were monitored daily until day 40 and then slaughtered on day 41. Total faecal worm egg output, total production of larvae recovered from faecal cultures, total post-mortem worm burdens and the per capita fecundity of female worms were estimated. The toxicity of the plant species for the goats was measured by histopathological analyses of liver and kidney samples. Results showed that goats feeding on the plant material rich in plant secondary metabolites had significantly lower egg output compared to the control goats (P0.05), the per capita fecundity was significantly reduced by E. corymbia, A. nilotica and A. salicina (Pgoats can benefit from the short-term ingestion of plant secondary metabolites, which reduce the total faecal egg output and thus decrease the potential for re-infection from the pasture. Crown Copyright © 2012. Published by Elsevier B.V. All

  3. Rethinking plant functional types in Earth System Models: pan-tropical analysis of tree survival across environmental gradients

    Science.gov (United States)

    Johnson, D. J.; Needham, J.; Xu, C.; Davies, S. J.; Bunyavejchewin, S.; Giardina, C. P.; Condit, R.; Cordell, S.; Litton, C. M.; Hubbell, S.; Kassim, A. R. B.; Shawn, L. K. Y.; Nasardin, M. B.; Ong, P.; Ostertag, R.; Sack, L.; Tan, S. K. S.; Yap, S.; McDowell, N. G.; McMahon, S.

    2016-12-01

    Terrestrial carbon cycling is a function of the growth and survival of trees. Current model representations of tree growth and survival at a global scale rely on coarse plant functional traits that are parameterized very generally. In view of the large biodiversity in the tropical forests, it is important that we account for the functional diversity in order to better predict tropical forest responses to future climate changes. Several next generation Earth System Models are moving towards a size-structured, trait-based approach to modelling vegetation globally, but the challenge of which and how many traits are necessary to capture forest complexity remains. Additionally, the challenge of collecting sufficient trait data to describe the vast species richness of tropical forests is enormous. We propose a more fundamental approach to these problems by characterizing forests by their patterns of survival. We expect our approach to distill real-world tree survival into a reasonable number of functional types. Using 10 large-area tropical forest plots that span geographic, edaphic and climatic gradients, we model tree survival as a function of tree size for hundreds of species. We found surprisingly few categories of size-survival functions emerge. This indicates some fundamental strategies at play across diverse forests to constrain the range of possible size-survival functions. Initial cluster analysis indicates that four to eight functional forms are necessary to describe variation in size-survival relations. Temporal variation in size-survival functions can be related to local environmental variation, allowing us to parameterize how demographically similar groups of species respond to perturbations in the ecosystem. We believe this methodology will yield a synthetic approach to classifying forest systems that will greatly reduce uncertainty and complexity in global vegetation models.

  4. Germination, survival and growth of three vascular plants on biological soil crusts from a Mexican tropical desert.

    Science.gov (United States)

    Godínez-Alvarez, H; Morín, C; Rivera-Aguilar, V

    2012-01-01

    Information about the effects of biological soil crusts (BSC) on germination, seedling survival and growth of vascular plants is controversial because they can have positive, neutral or negative effects. This controversy may be because most studies conducted until now have just analysed one or two recruitment stages independently. To understand the BSC effects on vascular plants, it is necessary to consider each stage of the recruitment process and synthesise all this information. The goal of this study was twofold. First, we analyse germination, seedling survival and growth of three vascular plants (Agave marmorata, Prosopis laevigata and Neobuxbaumia tetetzo) on BSC (cyanobacteria and mixed crust) from a tropical desert region of south-central México. Second, we synthesise the information to determine the total effect of BSC on plant species performance. We conducted experiments under controlled conditions to evaluate the proportion of germinated seeds, proportion of surviving seedlings and seedling dry weight in BSC and bare soil. Results showed that BSC have different effects on germination, seedling survival and growth of plant species. Plant species performance was qualitatively higher on BSC than bare soil. The highest performance of A. marmorata and P. laevigata was observed on cyanobacteria and mixed crusts, respectively. The highest performance of N. tetetzo was on both crust types. © 2011 German Botanical Society and The Royal Botanical Society of the Netherlands.

  5. Woody Vegetation Die off and Regeneration in Response to Rainfall Variability in the West African Sahel

    Directory of Open Access Journals (Sweden)

    Martin Brandt

    2017-01-01

    Full Text Available The greening in the Senegalese Sahel has been linked to an increase in net primary productivity, with significant long-term trends being closely related to the woody strata. This study investigates woody plant growth and mortality within greening areas in the pastoral areas of Senegal, and how these dynamics are linked to species diversity, climate, soil and human management. We analyse woody cover dynamics by means of multi-temporal and multi-scale Earth Observation, satellite based rainfall and in situ data sets covering the period 1994 to 2015. We find that favourable conditions (forest reserves, low human population density, sufficient rainfall led to a rapid growth of Combretaceae and Balanites aegyptiaca between 2000 and 2013 with an average increase of 4% woody cover. However, the increasing dominance and low drought resistance of drought prone species bears the risk of substantial woody cover losses following drought years. This was observed in 2014–2015, with a die off of Guiera senegalensis in most places of the study area. We show that woody cover and woody cover trends are closely related to mean annual rainfall, but no clear relationship with rainfall trends was found over the entire study period. The observed spatial and temporal variation contrasts with the simplified labels of “greening” or “degradation”. While in principal a low woody plant diversity negatively impacts regional resilience, the Sahelian system is showing signs of resilience at decadal time scales through widespread increases in woody cover and high regeneration rates after periodic droughts. We have reaffirmed that the woody cover in Sahel responds to its inherent climatic variability and does not follow a linear trend.

  6. Woody vegetation die off and regeneration in response to rainfall variability in the west African Sahel

    Science.gov (United States)

    Brandt, Martin; Tappan, G. Gray; Aziz Diouf, Abdoul; Beye, Gora; Mbow, Cheikh; Fensholt, Rasmus

    2017-01-01

    The greening in the Senegalese Sahel has been linked to an increase in net primary productivity, with significant long-term trends being closely related to the woody strata. This study investigates woody plant growth and mortality within greening areas in the pastoral areas of Senegal, and how these dynamics are linked to species diversity, climate, soil and human management. We analyse woody cover dynamics by means of multi-temporal and multi-scale Earth Observation, satellite based rainfall and in situ data sets covering the period 1994 to 2015. We find that favourable conditions (forest reserves, low human population density, sufficient rainfall) led to a rapid growth of Combretaceae and Balanites aegyptiaca between 2000 and 2013 with an average increase of 4% woody cover. However, the increasing dominance and low drought resistance of drought prone species bears the risk of substantial woody cover losses following drought years. This was observed in 2014–2015, with a die off of Guiera senegalensis in most places of the study area. We show that woody cover and woody cover trends are closely related to mean annual rainfall, but no clear relationship with rainfall trends was found over the entire study period. The observed spatial and temporal variation contrasts with the simplified labels of “greening” or “degradation”. While in principal a low woody plant diversity negatively impacts regional resilience, the Sahelian system is showing signs of resilience at decadal time scales through widespread increases in woody cover and high regeneration rates after periodic droughts. We have reaffirmed that the woody cover in Sahel responds to its inherent climatic variability and does not follow a linear trend.

  7. Phylogenetic and Functional Diversity of Fleshy-Fruited Plants Are Positively Associated with Seedling Diversity in a Tropical Montane Forest

    Directory of Open Access Journals (Sweden)

    Marcia C. Muñoz

    2017-08-01

    Full Text Available Mutualistic interactions between plants and animals can affect both plant and animal communities, and potentially leave imprints on plant demography. Yet, no study has simultaneously tested how trait variation in plant resources shapes the diversity of animal consumers, and how these interactions influence seedling recruitment. Here, we analyzed whether (i phylogenetic diversity and functional diversity of fruiting plants were correlated with the corresponding diversity of frugivorous birds, and (ii whether phylogenetic diversity and functional identity of plant and bird communities influenced the corresponding diversity and identity of seedling communities. We recorded mutualistic interactions between fleshy-fruited plants and frugivorous birds and seedling communities in 10 plots along an elevational gradient in the Colombian Andes. We built a phylogeny for plants/seedlings and birds and measured relevant morphological plant and bird traits that influence plant-bird interactions and seedling recruitment. We found that phylogenetic diversity and functional diversity of frugivorous birds were positively associated with the corresponding diversities of fruiting plants, consistent with a bottom-up effect of plants on birds. Moreover, the phylogenetic diversity of seedlings was related to the phylogenetic diversity of plants, but was unrelated to the phylogenetic diversity of frugivorous birds, suggesting that top-down effects of animals on seedlings were weak. Mean seed mass of seedling communities was positively associated with the mean fruit mass of plants, but was not associated with the mean avian body mass in the frugivore communities. Our study shows that variation in the traits of fleshy-fruited plants was associated with the diversity of frugivorous birds and affected the future trajectory of seedling recruitment, whereas the morphological traits of animal seed dispersers were unrelated to the phylogenetic and functional structure of

  8. Seasonal variation in soil and plant water potentials in a Bolivian tropical moist and dry forest

    NARCIS (Netherlands)

    Markesteijn, L.; Iraipi, J.; Bongers, F.; Poorter, L.

    2010-01-01

    We determined seasonal variation in soil matric potentials (¿soil) along a topographical gradient and with soil depth in a Bolivian tropical dry (1160 mm y-1 rain) and moist forest (1580 mm y-1). In each forest we analysed the effect of drought on predawn leaf water potentials (¿pd) and drought

  9. Woody encroachment in northern Great Plains grasslands: Perceptions, actions, and needs

    Science.gov (United States)

    Symstad, Amy J.; Leis, Sherry A.

    2017-01-01

    The United States Northern Great Plains (NGP) has a high potential for landscape-scale conservation, but this grassland landscape is threatened by encroachment of woody species. We surveyed NGP land managers to identify patterns in, and illustrate a broad range of, individual managers' perceptions on (1) the threat of woody encroachment to grasslands they manage, and (2) what management practices they use that may influence woody encroachment in this region. In the 34 surveys returned, which came from predominantly public lands in the study area, 79% of responses reported moderate or substantial woody encroachment. Eastern redcedar (Juniperus virginiana) and Rocky Mountain juniper (Juniperus scopulorum) were the most problematic encroachers. Thirty-one survey respondents said that prescribed fire was used on the lands they manage, and 64% of these responses reported that controlling woody encroachment was a fire management objective. However, only 18% of survey respondents using prescribed fire were achieving their desired fire return interval. Most respondents reported using mechanical and/or chemical methods to control woody species. In contrast to evidence from the central and southern Great Plains, few survey respondents viewed grazing as affecting encroachment. Although the NGP public land managers we surveyed clearly recognize woody encroachment as a problem and are taking steps to address it, many feel that the rate of their management is not keeping pace with the rate of encroachment. Developing strategies for effective woody plant control in a variety of NGP management contexts requires filling ecological science gaps and overcoming societal barriers to using prescribed fire.

  10. Plant available nitrogen from anaerobically digested sludge and septic tank sludge applied to crops grown in the tropics.

    Science.gov (United States)

    Sripanomtanakorn, S; Polprasert, C

    2002-04-01

    Agricultural land is an attractive alternative for the disposal of biosolids since it utilises the recyclable nutrients in the production of crops. In Thailand and other tropical regions, limited field-study information exists on the effect of biosolids management strategies on crop N utilisation and plant available N (PAN) of biosolids. A field study was conducted to quantify the PAN of the applied biosolids, and to evaluate the N uptake rates of some tropical crops. Sunflower (Helianthus annuus) and tomato (Lycopersicon esculentum) were chosen in this study. Two types of biosolids used were: anaerobically digested sludge and septic tank sludge. The soil is acid sulfate and is classified as Sulfic Tropaquepts with heavy clay in texture. The anaerobically digested sludge applied rates were: 0, 156 and 312 kg N ha(-1) for the sunflower plots, and 0, 586, and 1172 kg N ha(-1) for the tomato plots. The septic tank sludge applied rates were: 0, 95 and 190 kg N ha(-1) for the sunflower plots, and 0, 354 and 708 kg N ha(-1) for the tomato plots, respectively. The results indicated the feasibility of applying biosolids to grow tropical crops. The applications of the anaerobically digested sludge and the septic tank sludge resulted in the yields of sunflower seeds and tomato fruits and the plant N uptakes comparable or better than that applied with only the chemical fertiliser. The estimated PAN of the anaerobically digested sludge was about 27-42% of the sludge organic N during the growing season. For the septic tank sludge, the PAN was about 15-58% of the sludge organic N. It is interesting to observe that an increase of the rate of septic tank sludge incorporated into this heavy clay soil under the cropping system resulted in the decrease of N mineralisation rate. This situation could cause the reduction of yield and N uptake of crops.

  11. High yielding tropical energy crops for bioenergy production: Effects of plant components, harvest years and locations on biomass composition.

    Science.gov (United States)

    Surendra, K C; Ogoshi, Richard; Zaleski, Halina M; Hashimoto, Andrew G; Khanal, Samir Kumar

    2018-03-01

    The composition of lignocellulosic feedstock, which depends on crop type, crop management, locations and plant parts, significantly affects the conversion efficiency of biomass into biofuels and biobased products. Thus, this study examined the composition of different parts of two high yielding tropical energy crops, Energycane and Napier grass, collected across three locations and years. Significantly higher fiber content was found in the leaves of Energycane than stems, while fiber content was significantly higher in the stems than the leaves of Napier grass. Similarly, fiber content was higher in Napier grass than Energycane. Due to significant differences in biomass composition between the plant parts within a crop type, neither biological conversion, including anaerobic digestion, nor thermochemical pretreatment alone is likely to efficiently convert biomass components into biofuels and biobased products. However, combination of anaerobic digestion with thermochemical conversion technologies could efficiently utilize biomass components in generating biofuels and biobased products. Copyright © 2017 Elsevier Ltd. All rights reserved.

  12. Effect of submergence-emergence sequence and organic matter or aluminosilicate amendment on metal uptake by woody wetland plant species from contaminated sediments

    International Nuclear Information System (INIS)

    Vandecasteele, Bart; Du Laing, Gijs; Tack, Filip M.G.

    2007-01-01

    Site-specific hydrological conditions affect the availability of trace metals for vegetation. In a greenhouse experiment, the effect of submersion on the metal uptake by the wetland plant species Salix cinerea and Populus nigra grown on a contaminated dredged sediment-derived soil and on an uncontaminated soil was evaluated. An upland hydrological regime for the polluted sediment caused elevated Cd concentrations in leaves and cuttings for both species. Emergence and soil oxidation after initial submersion of a polluted sediment resulted in comparable foliar Cd and Zn concentrations for S. cinerea as for the constant upland treatment. The foliar Cd and Zn concentrations were clearly higher than for submerged soils after initial upland conditions. These results point at the importance of submergence-emergence sequence for plant metal availability. The addition of foliar-based organic matter or aluminosilicates to the polluted sediment-derived soil in upland conditions did not decrease Cd and Zn uptake by S. cinerea. - The effect of a wetland hydrological regime on Cd uptake was similar for Populus nigra and Salix cinerea

  13. Nitrogen to phosphorus ratio of plant biomass versus soil solution in a tropical pioneer tree, Ficus insipida.

    Science.gov (United States)

    Garrish, Valerie; Cernusak, Lucas A; Winter, Klaus; Turner, Benjamin L

    2010-08-01

    It is commonly assumed that the nitrogen to phosphorus (N:P) ratio of a terrestrial plant reflects the relative availability of N and P in the soil in which the plant grows. Here, this was assessed for a tropical pioneer tree, Ficus insipida. Seedlings were grown in sand and irrigated with nutrient solutions containing N:P ratios ranging from 100. The experimental design further allowed investigation of physiological responses to N and P availability. Homeostatic control over N:P ratios was stronger in leaves than in stems or roots, suggesting that N:P ratios of stems and roots are more sensitive indicators of the relative availability of N and P at a site than N:P ratios of leaves. The leaf N:P ratio at which the largest plant dry mass and highest photosynthetic rates were achieved was approximately 11, whereas the corresponding whole-plant N:P ratio was approximately 6. Plant P concentration varied as a function of transpiration rate at constant nutrient solution P concentration, possibly due to transpiration-induced variation in the mass flow of P to root surfaces. The transpiration rate varied in response to nutrient solution N concentration, but not to nutrient solution P concentration, demonstrating nutritional control over transpiration by N but not P. Water-use efficiency varied as a function of N availability, but not as a function of P availability.

  14. Restoration of degraded drylands through exclosures enhancing woody species diversity and soil nutrients in the highlands of Tigray, Northern Ethiopia

    Directory of Open Access Journals (Sweden)

    Kide M. Gebremedihin

    2018-02-01

    Full Text Available Exclusion of grazing animals and tree plantations were among the methods used for the rehabilitation of degraded lands in tropical semiarid areas. Exclosures can foster secondary forest succession by improving soil conditions, attracting seed-dispersal agents and modifying microclimate for understory growth. This paper compares the woody species diversity and soil chemical properties under exclosure with increasing age and grazing land at different slope positions. The study has been conducted in northern Ethiopia from 12 exclosure sites paired each with adjacent grazing land with four treatments replicated three times. In the entire study 216 plots were examined of which 108 were in exclosures and 108 in communal grazing lands.There were four age classes and three slope positions in each of the landuses. Vegetation data were collected using plots measuring 100 m2. Soils for physicochemical properties were collected from the four corners and center of 5 × 5m plots which was inside the 10 × 10m plot. A total of 61 woody plant species belonging to 41 families were recorded. Diversity and species richness were higher in the exclosures than in grazing lands. Among exclosures these parameters were higher in exclosures older than 30 years and at the foot of the slope. Grazing lands, the youngest exclosures and upper elevation gradient recorded lower values. Chemical soil properties were significantly higher in the exclosures, among them in the oldest exclosures and at foot elevation (except for P than these were in the grazing land, the youngest exclosures and upper parts of slopes respectively. Exclosures are instrumental to improve the woody species diversity and soil chemical properties in the drylands.

  15. Genetical, cytological and physiological studies on the induced mutants with special regard to effective methods for obtaining useful mutants in perennial woody plant

    International Nuclear Information System (INIS)

    Kukimura, H.; Ikeda, F.; Fujita, H.; Maeta, T.; Nakajima, K.; Katagiri, K.; Nakahira, K.; Somegou, M.

    1976-01-01

    The plants studied included apple trees, cryptomeria (japanese cedar) and mulberry. In apple, dwarf and compact types of mutants from cv. Fuji were found to be graft incompatible on Maruba-kaido(Malus prunifolia) rootstock. In Sunki mandarin(Citrus sunki), the number of nucellar embryo per seed was affected by gamma-irradiation, and morphological mutants from nucellar seedlings were obtained at high rate by irradiation at floral bud stage with 2kR exposure. In Cryptomeria, re-irradiated waxless mutants by gamma-rays showed very high rate of somatic mutation when compared to other morphological mutants. Pollen sterility and pollen shaped PMC were found in the most of gamma-induced-mutants. Mutants forming pollen shaped PMC had a genetical tendency of continuous male flower bud formation for a longer term. With mulberry, time of sprouting of induced mutants differed from the originals. Ability of root initiation of semi-softwood cuttings in morphological mutants were tested. Cytochimera induction were found at considerably high rate when actively growing diploid plants were irradiated by gamma-rays. Eight kinds of cytochimeras were induced. Frequency of 2-4-4 was extremely high(approx. 50%), then 4-2-2 and 2-4-2 chimeras followed. Seven kinds were induced by semi-acute irradiation(200R/h), while 4 kinds by acute irradiation(5kR/h). By breeding test it was cleared that the elongate and entire leaf was sexually transmissible, whereas the 'dwarf' was not obvious and the 'marginally curledleaf' was not transmissible. Pyronin-methylgreen staining method proved to be useful in some morphological mutants to distinguish the histo-genetical differences which exist in the shoot apex.

  16. Radiation preservation of foods of plant origin. III. Tropical fruits: bananas, mangoes, and papayas

    International Nuclear Information System (INIS)

    Thomas, P.

    1986-01-01

    The current status of research on the use of ionizing radiation for shelf life improvement and disinfestation of fresh tropical fruits like bananas, mangoes, and papayas are reviewed. The aspects covered are influence of maturity and physiological state of the fruits on delayed ripening and tolerance to radiation; varietal responses; changes in chemical constituents, volatiles, respiration, and ethylene evolution; biochemical mechanisms of delayed ripening and browning of irradiated fruits; and organoleptic quality. The efficacy of the combination of hot water dip and radiation treatments for control of postharvest fungal diseases are considered. The immediate potential of radiation as a quarantine treatment, in place of the currently used chemical fumigants, for disinfestation of fruit flies and mango seed weevil are discussed. Future prospects for irradiation of tropical fruits are discussed in the light of experience gained from studies conducted in different countries.146 references

  17. Down woody materials as an indicator of wildlife habitat, fuels, and carbon stocks of the United States

    Science.gov (United States)

    Christopher W. Woodall

    2007-01-01

    Why Are Down Woody Materials Important? The down woody materials (DWM) indicator is used to estimate the quantity of deadorganic material (resulting from plant mortality and leaf turnover) in forest ecosystems of the United States. The DWM indicator, coupled with other components of the enhanced Forest Inventory and Analysis (FIA) program, can indicate the...

  18. First steps in studying the origins of secondary woodiness in Begonia (Begoniaceae): combining anatomy, phylogenetics, and stem transcriptomics

    Science.gov (United States)

    Catherine Kidner; Andrew Groover; Daniel C. Thomas; Katie Emelianova; Claudia Soliz-Gamboa; Frederic Lens

    2015-01-01

    Since Darwin's observation that secondary woodiness is common on islands, the evolution of woody plants from herbaceous ancestors has been documented in numerous angiosperm groups. However, the evolutionary processes that give rise to this phenomenon are poorly understood. To begin addressing this we have used a range of approaches to study the anatomical and...

  19. Micro-organisms behind the pollination scenes: microbial imprint on floral nectar sugar variation in a tropical plant community.

    Science.gov (United States)

    Canto, A; Herrera, C M

    2012-11-01

    Variation in the composition of floral nectar reflects intrinsic plant characteristics as well as the action of extrinsic factors. Micro-organisms, particularly yeasts, represent one extrinsic factor that inhabit the nectar of animal-pollinated flowers worldwide. In this study a 'microbial imprint hypothesis' is formulated and tested, in which it is proposed that natural community-wide variation in nectar sugar composition will partly depend on the presence of yeasts in flowers. Occurrence and density of yeasts were studied microscopically in single-flower nectar samples of 22 animal-pollinated species from coastal xeric and sub-humid tropical habitats of the Yucatán Peninsula, Mexico. Nectar sugar concentration and composition were concurrently determined on the same samples using high-performance liquid chromatography (HPLC) methods. Microscopical examination of nectar samples revealed the presence of yeasts in nearly all plant species (21 out of 22 species) and in about half of the samples examined (51·8 % of total, all species combined). Plant species and individuals differed significantly in nectar sugar concentration and composition, and also in the incidence of nectar yeasts. After statistically controlling for differences between plant species and individuals, nectar yeasts still accounted for a significant fraction of community-wide variance in all nectar sugar parameters considered. Significant yeast × species interactions on sugar parameters revealed that plant species differed in the nectar sugar correlates of variation in yeast incidence. The results support the hypothesis that nectar yeasts impose a detectable imprint on community-wide variation in nectar sugar composition and concentration. Since nectar sugar features influence pollinator attraction and plant reproduction, future nectar studies should control for yeast presence and examine the extent to which microbial signatures on nectar characteristics ultimately have some influence on

  20. Availability and use of woody plants in a agrarian reform settlement in the cerrado of the state of Goiás, Brazil

    Directory of Open Access Journals (Sweden)

    Vanessa Pessanha Tunholi

    2013-09-01

    Full Text Available Protected areas are important sources providing plant resources for human populations, and contributing to the livelihood and income of families. To test the ecological apparency hypothesis, that there is positive relationship between the visibility of a species and its use, we conducted an ethnobotanical survey in the protected area of the Itaúna rural settlement in the municipality of Planaltina, in the state of Goiás, in central Brazil. The phytosociological parameters were obtained in 5.6 ha area of the Brazilian cerrado (savanna, and the ethnobotanical survey conducted with semi-structured interviews with 75 people. There was a weak positive correlation between the use value and the phytosociological parameters. A principal component analysis showed that seven species (Pterodon pubescens, Hancornia speciosa, Hymenaea stigonocarpa, Eugenia dysenterica, Annona crassiflora, Stryphnodendron adstringens and Solanum lycocarpum have high use value, despite having low density, dominance and frequency. Nineteen species showed a positive relationship between their use value and their phytosociological parameters. The relationship between vegetation structure and use value differed among species in the protected area, indicating that more attention should be paid to those under more pressure, with low abundance. Further studies of these seven species should be conducted to determine whether human pressure is affecting populations structures and to define management strategies.

  1. Perspectives on screening winter-flood-tolerant woody species in the riparian protection forests of the three gorges reservoir.

    Science.gov (United States)

    Yang, Fan; Wang, Yong; Chan, Zhulong

    2014-01-01

    The establishment of riparian protection forests in the Three Gorges Reservoir (TGR) is an ideal measure to cope with the eco-environmental problems of the water-level fluctuation zone (WLFZ). Thus, the information for screening winter-flood-tolerant woody plant species is useful for the recovery and re-establishment of the riparian protection forests in the TGR WLFZ. Therefore, we discussed the possibilities of constructing and popularizing riparian protection forests in the TGR WLFZ from several aspects, including the woody plant species distribution in the WLFZ, the survival rate analyses of suitable candidate woody species under controlled flooding conditions, the survival rate investigation of some woody plant species planted in the TGR WLFZ, and the physiological responses of some woody plant species during the recovery stage after winter floods. The results of woody species investigation showed that most woody plant species that existed as annual seedlings in the TGR WLFZ are not suitable candidates for the riparian protection forests. However, arbor species (e.g., Salix matsudana, Populus×canadensis, Morus alba, Pterocarya stenoptera, Taxodium ascendens, and Metasequoia glyptostroboides) and shrub species (e.g., Salix variegata, Distylium chinensis, Lycium chinense, Myricaria laxiflora, and Rosa multiflora) might be considered suitable candidates for the riparian protection forests in the TGR WLFZ by survival rate analyses under controlled winter flooding conditions, and survival rate investigations of woody plant species planted in the TGR WLFZ, respectively. Physiological analyses showed that P.×canadensis, M. alba, L. chinense, and S. variegata could develop specific self-repairing mechanisms to stimulate biomass accumulation and carbohydrate synthesis via the increases in chlorophyll pigments and photosynthesis during recovery after winter floods. Our results suggested these woody plant species could endure the winter flooding stress and recover well

  2. Perspectives on screening winter-flood-tolerant woody species in the riparian protection forests of the three gorges reservoir.

    Directory of Open Access Journals (Sweden)

    Fan Yang

    Full Text Available The establishment of riparian protection forests in the Three Gorges Reservoir (TGR is an ideal measure to cope with the eco-environmental problems of the water-level fluctuation zone (WLFZ. Thus, the information for screening winter-flood-tolerant woody plant species is useful for the recovery and re-establishment of the riparian protection forests in the TGR WLFZ. Therefore, we discussed the possibilities of constructing and popularizing riparian protection forests in the TGR WLFZ from several aspects, including the woody plant species distribution in the WLFZ, the survival rate analyses of suitable candidate woody species under controlled flooding conditions, the survival rate investigation of some woody plant species planted in the TGR WLFZ, and the physiological responses of some woody plant species during the recovery stage after winter floods. The results of woody species investigation showed that most woody plant species that existed as annual seedlings in the TGR WLFZ are not suitable candidates for the riparian protection forests. However, arbor species (e.g., Salix matsudana, Populus×canadensis, Morus alba, Pterocarya stenoptera, Taxodium ascendens, and Metasequoia glyptostroboides and shrub species (e.g., Salix variegata, Distylium chinensis, Lycium chinense, Myricaria laxiflora, and Rosa multiflora might be considered suitable candidates for the riparian protection forests in the TGR WLFZ by survival rate analyses under controlled winter flooding conditions, and survival rate investigations of woody plant species planted in the TGR WLFZ, respectively. Physiological analyses showed that P.×canadensis, M. alba, L. chinense, and S. variegata could develop specific self-repairing mechanisms to stimulate biomass accumulation and carbohydrate synthesis via the increases in chlorophyll pigments and photosynthesis during recovery after winter floods. Our results suggested these woody plant species could endure the winter flooding stress

  3. Flax fibers as a raw material: How to bleach efficiently a non-woody plant to obtain high-quality pulp

    International Nuclear Information System (INIS)

    Fillat, Ursula; Pepio, Montserrat; Vidal, Teresa; Roncero, M. Blanca

    2010-01-01

    Fiber crops constitute a good alternative to wood fiber for manufacturing pulp and paper. In fact, fiber plants like flax surpass wood fiber in some technical respects and also in the environmental benignity of their processing. In this work, flax fiber was subjected to environmentally friendly bleaching sequences in order to obtain a high-quality pulp. The totally chlorine-free sequences (TCF) used for this purpose (LE and LRE) included an enzyme treatment with laccase in the presence of HBT as mediator (L stage), an alkaline extraction (E stage) and a reductive treatment with NaBH 4 (R stage). The operating conditions for the L stage (laccase and HBT doses, reaction time and oxygen pressure) were optimised by using a sequential statistical plan to assess their influence on pulp properties after the E stage. Mathematical models accurately predicting brightness and kappa number in terms of the previous four variables were developed based on which the most influential factors were the laccase and HBT rates, and treatment time. By contrast, oxygen pressures of 0.2-0.6 MPa in the reactor had no effect on brightness or kappa number. The flax pulp obtained contained some oxidized cellulose that was partially degraded in the alkaline extraction step and reduced viscosity as a result. The viscosity loss associated with the presence of oxidized cellulose in the control and enzyme-treated pulp samples was efficiently recovered by using a reductive stage with sodium borohydride. Effluent was also analysed in order to assess the environmental impact of the process.

  4. Leaf quality and insect herbivory in model tropical plant communities after long-term exposure to elevated atmospheric CO2.

    Science.gov (United States)

    Arnone, J A; Zaller, J G; Körner, Ch; Ziegler, C; Zandt, H

    1995-09-01

    Results from laboratory feeding experiments have shown that elevated atmospheric carbon dioxide can affect interactions between plants and insect herbivores, primarily through changes in leaf nutritional quality occurring at elevated CO 2 . Very few data are available on insect herbivory in plant communities where insects can choose among species and positions in the canopy in which to feed. Our objectives were to determine the extent to which CO 2 -induced changes in plant communities and leaf nutritional quality may affect herbivory at the level of the entire canopy. We introduced equivalent populations of fourth instar Spodoptera eridania, a lepidopteran generalist, to complex model ecosystems containing seven species of moist tropical plants maintained under low mineral nutrient supply. Larvae were allowed to feed freely for 14 days, by which time they had reached the seventh instar. Prior to larval introductions, plant communities had been continuously exposed to either 340 μl CO 2 l -1 or to 610 μl CO 2 l -1 for 1.5 years. No major shifts in leaf nutritional quality [concentrations of N, total non-structural carbohydrates (TNC), sugar, and starch; ratios of: C/N, TNC/N, sugar/N, starch/N; leaf toughness] were observed between CO 2 treatments for any of the species. Furthermore, no correlations were observed between these measures of leaf quality and leaf biomass consumption. Total leaf area and biomass of all plant communities were similar when caterpillars were introduced. However, leaf biomass of some species was slightly greater-and for other species slightly less (e.g. Cecropia peltata)-in communities exposed to elevated CO 2 . Larvae showed the strongest preference for C. peltata leaves, the plant species that was least abundant in all communites, and fed relatively little on plants species which were more abundant. Thus, our results indicate that leaf tissue quality, as described by these parameters, is not necessarily affected by elevated CO 2 under

  5. Unique competitive effects of lianas and trees in a tropical forest understory.

    Science.gov (United States)

    Wright, Alexandra; Tobin, Mike; Mangan, Scott; Schnitzer, Stefan A

    2015-02-01

    Lianas are an important component of tropical forests, contributing up to 25% of the woody stems and 35% of woody species diversity. Lianas invest less in structural support but more in leaves compared to trees of similar biomass. These physiological and morphological differences suggest that lianas may interact with neighboring plants in ways that are different from similarly sized trees. However, the vast majority of past liana competition studies have failed to identify the unique competitive effects of lianas by controlling for the amount of biomass removed. We assessed liana competition in the forest understory over the course of 3 years by removing liana biomass and an equal amount of tree biomass in 40 plots at 10 sites in a secondary tropical moist forest in central Panama. We found that growth of understory trees and lianas, as well as planted seedlings, was limited due to competitive effects from both lianas and trees, though the competitive impacts varied by species, season, and size of neighbors. The removal of trees resulted in greater survival of planted seedlings compared to the removal of lianas, apparently related to a greater release from competition for light. In contrast, lianas had a species-specific negative effect on drought-tolerant Dipteryx oleifera seedlings during the dry season, potentially due to competition for water. We conclude that, at local scales, lianas and trees have unique and differential effects on understory dynamics, with lianas potentially competing more strongly during the dry season, and trees competing more strongly for light.

  6. Calibration and validation of models for short-term decomposition and N mineralization of plant residues in the tropics

    Directory of Open Access Journals (Sweden)

    Alexandre Ferreira do Nascimento

    2012-12-01

    Full Text Available Insight of nutrient release patterns associated with the decomposition of plant residues is important for their effective use as a green manure in food production systems. Thus, this study aimed to evaluate the ability of the Century, APSIM and NDICEA simulation models for predicting the decomposition and N mineralization of crop residues in the tropical Atlantic forest biome, Brazil. The simulation models were calibrated based on actual decomposition and N mineralization rates of three types of crop residues with different chemical and biochemical composition. The models were also validated for different pedo-climatic conditions and crop residues conditions. In general, the accuracy of decomposition and N mineralization improved after calibration. Overall RMSE values for the decomposition and N mineralization of the crop materials varied from 7.4 to 64.6% before models calibration compared to 3.7 to 16.3 % after calibration. Therefore, adequate calibration of the models is indispensable for use them under humid tropical conditions. The NDICEA model generally outperformed the other models. However, the decomposition and N mineralization was not very accurate during the first 30 days of incubation, especially for easily decomposable crop residues. An additional model variable may be required to capture initial microbiological growth as affected by the moisture dynamics of the residues, as is the case in surface residues decomposition models.

  7. The toughness of secondary cell wall and woody tissue

    OpenAIRE

    Lucas, P. W.; Tan, H. T. W.; Cheng, P. Y.

    1997-01-01

    The 'across grain' toughness of 51 woods has been determined on thin wet sections using scissors. The moisture content of sections and the varying sharpness of the scissor blades had little effect on the results. In thin sections (less than 0.6mm), toughness rose linearly with section thickness. The intercept toughness at zero thickness, estimated from regression analysis, was proportional to relative density, consistent with values reported for non-woody plant tissues. Extrapolation of the i...

  8. Testing the stress-gradient hypothesis during the restoration of tropical degraded land using the shrub Rhodomyrtus tomentosa as a nurse plant

    Science.gov (United States)

    Nan Liu; Hai Ren; Sufen Yuan; Qinfeng Guo; Long Yang

    2013-01-01

    The relative importance of facilitation and competition between pairwise plants across abiotic stress gradients as predicted by the stress-gradient hypothesis has been confirmed in arid and temperate ecosystems, but the hypothesis has rarely been tested in tropical systems, particularly across nutrient gradients. The current research examines the interactions between a...

  9. Alternative plant protein sources for pigs and chickens in the tropics – nutritional value and constraints: a review

    Directory of Open Access Journals (Sweden)

    Carlos E. Lascano

    2012-01-01

    Full Text Available In the tropics, a large number of smallholder farms contribute significantly to food security by raising pigs and poultry for domestic consumption and for sale on local markets. The high cost and, sometimes, the lack of availability of commercial protein supplements is one of the main limitations to efficient animal production by smallholders. Locally-grown forages and grain legumes offer ecological benefits such as nitrogen fixation, soil improvement, and erosion control which contribute to improve cropping efficiency. Besides these agronomical assets, they can be used as animal feeds in mixed farming systems. In this paper we review options to include locally-grown forages and grain legumes as alternative protein sources in the diets of pigs and poultry in order to reduce farmers’ dependence on externally-purchased protein concentrates. The potential nutritive value of a wide range of forages and grain legumes is presented and discussed. The influence of dietary fibre and plant secondary metabolites contents and their antinutritive consequences on feed intake, digestive processes and animal performances are considered according to the varying composition in those compounds of the different plant species and cultivars covered in this review. Finally, methods to overcome the antinutritive attributes of the plant secondary metabolites using heat, chemical or biological treatment are reviewed regarding their efficiency and their suitability in low input farming systems.

  10. Ecophysiology of two tropical species in an abandoned eucalypt plantation: effect of plant litter removal and seasonality

    Directory of Open Access Journals (Sweden)

    Frederico Lage-Pinto

    2015-05-01

    Full Text Available The effect of the removal of plant litter on photosynthetic variables (gas exchanges, chlorophyll a fluorescence, and content of photosynthetic pigments of the tropical species Xylopia sericea A. St.-Hil. and Siparuna guianensis Aubl. was evaluated in an abandoned plantation of eucalypt (Corymbia citriodora (Hook. K.D. Hill & L.A.S. Johnson (Myrtaceae. The study was conducted at the União Biological Reserve, Rio de Janeiro State, Brazil during the rainy and dry periods, after five years of litter removal. The removal of plant litter did not influence the ecophysiological responses of the species. There was however significant seasonal variation. During the dry period, intercellular CO2 concentration (Ci, transpiration (E, and stomatal conductance (gs were decreased, while intrinsic efficiency of water use (IWUE, non-photochemical quenching (NPQ, and carotenoid values increased, suggesting a protective strategy against stress. Nevertheless, the values for Fv/Fm (maximum quantum efficiency and Fm/Fo (ratio of fluorescence yields for open and closed states indicated that even during the dry period there was no reduction in photochemical activity in these species. Only S. guianensis exhibited a reduced net photosynthetic rate (A during the dry period. The data indicated that X. sericea was photosynthetically more efficient under conditions of low water availability and that a 5-year period of plant litter removal failed to produce differences in ecophysiological processes in the species analyzed.

  11. Optimizing NSSS power and turbine/generator performance for standardized nuclear power plant designs in tropical climates

    International Nuclear Information System (INIS)

    Parece, M.V.; Stack, T.G.; Huffman, A.D.

    2007-01-01

    The EPR was developed by AREVA as a standardized nuclear power plant design that could be deployed throughout the world. The first EPR is currently being constructed at Olkiluoto, Finland. Many of the plant systems for this first-of-a-kind unit are optimized for the climate and heat rejection method (once-through cooling) used at Olkiluoto. Two such systems are the Nuclear Steam Supply System (NSSS) and the Turbine/Generator (T/G) system. To achieve the EPR's target net electrical output for tropical climates and various condenser heat rejection methods, design studies were performed that showed that the NSSS and T/G system designs developed for the Olkiluoto site conditions required modification. The business case for EPR on U.S. sites where average ambient temperature is above 60 F, implies an economical design that provides an average net electrical output of at least 1600 MWe. It has been shown through parametric studies that the key features of the design needed to achieve this goal are: -) rated core thermal power of 4590 MWth, which is supported by plant systems, structures and components; -) the use of mechanical draft cooling towers rather than natural draft cooling towers; -) a low pressure turbine design with reduced exhaust annulus area; and -) a multi-pressure condenser configuration

  12. Plant cover and hydrological response in a seasonally dry tropical forest (SDTF = Cobertura vegetal e as respostas hidrológicas em floresta tropical sazonalmente seca (FTSS

    Directory of Open Access Journals (Sweden)

    Eunice Maia de Andrade

    2017-10-01

    Full Text Available The scarcity of information on the processes of rainfall-flow limits understanding of the hydrology of dry regions of the world. In order to minimise the problem, this study was developed to investigate the influence of the characteristics of rainfall events and plant cover on the effective precipitation (Pe in a seasonally dry tropical forest (SDTF in the Northeast of Brazil. The study was carried out in two paired watersheds, one with SDTF under regeneration for 35 years (CR35 and the other under thinned SDTF for 5 years (TC. A historical series of five years (2009-2013 was analysed, with a total of 203 rainfall events, where only those rainfall events that generated a Pe > 1.0 mm were considered. CR35 had a greater number of Pe events (47 than TC (35. Rainfall depth and intensity were the factors that best explained the effective precipitation under both types of vegetation cover. The influence of herbaceous vegetation on the reduction of surface runoff was demonstrated by the smaller runoff depth and the greater potential for soil water storage in the watershed under thinned Caatinga. This fact leads to the conclusion that the technique of thinning is suitable management for Caatinga vegetation, and is capable of promoting the retention of soil water. = A escassez de informações sobre os processos chuva-deflúvio é uma limitação no entendimento da hidrologia das regiões secas do globo terrestre. Buscando minimizar esta problemática, desenvolveuse este estudo objetivando investigar as influências das características dos eventos pluviométricos e da cobertura vegetal na precipitação efetiva (Pe em floresta tropical sazonalmente seca (FTSS, no nordeste do Brasil. O estudo foi realizado em duas microbacias emparelhadas, uma com FTSS em regeneração há 35 anos (CR35 e outra com FTSS raleada há 5 anos (CR. Foi analisada uma série histórica de cinco anos (2009-2013, com um total de 203 eventos pluviométricos, sendo considerados

  13. Potential for Coal Power Plants to Co-Fire with Woody Biomass in the U. S. North, 2010-2030: A Technical Document Supporting the Northern Forest Futures Project

    Science.gov (United States)

    Michael E. Goerndt; Francisco X. Aguilar; Kenneth E. Skog

    2015-01-01

    Future use of woody biomass to produce electric power in the U.S. North can have an important influence on timber production, carbon storage in forests, and net carbon emissions from producing electric power. The Northern Forest Futures Project (NFFP) has provided regional- and state-level projections of standing forest biomass, land-use change, and timber harvest,...

  14. Transcriptome profiling of low temperature-treated cassava apical shoots showed dynamic responses of tropical plant to cold stress

    Directory of Open Access Journals (Sweden)

    An Dong

    2012-02-01

    Full Text Available Abstract Background Cassava is an important tropical root crop adapted to a wide range of environmental stimuli such as drought and acid soils. Nevertheless, it is an extremely cold-sensitive tropical species. Thus far, there is limited information about gene regulation and signalling pathways related to the cold stress response in cassava. The development of microarray technology has accelerated the study of global transcription profiling under certain conditions. Results A 60-mer oligonucleotide microarray representing 20,840 genes was used to perform transcriptome profiling in apical shoots of cassava subjected to cold at 7°C for 0, 4 and 9 h. A total of 508 transcripts were identified as early cold-responsive genes in which 319 sequences had functional descriptions when aligned with Arabidopsis proteins. Gene ontology annotation analysis identified many cold-relevant categories, including 'Response to abiotic and biotic stimulus', 'Response to stress', 'Transcription factor activity', and 'Chloroplast'. Various stress-associated genes with a wide range of biological functions were found, such as signal transduction components (e.g., MAP kinase 4, transcription factors (TFs, e.g., RAP2.11, and reactive oxygen species (ROS scavenging enzymes (e.g., catalase 2, as well as photosynthesis-related genes (e.g., PsaL. Seventeen major TF families including many well-studied members (e.g., AP2-EREBP were also involved in the early response to cold stress. Meanwhile, KEGG pathway analysis uncovered many important pathways, such as 'Plant hormone signal transduction' and 'Starch and sucrose metabolism'. Furthermore, the expression changes of 32 genes under cold and other abiotic stress conditions were validated by real-time RT-PCR. Importantly, most of the tested stress-responsive genes were primarily expressed in mature leaves, stem cambia, and fibrous roots rather than apical buds and young leaves. As a response to cold stress in cassava, an increase

  15. Scatter hoarding of seeds confers survival advantages and disadvantages to large-seeded tropical plants at different life stages.

    Directory of Open Access Journals (Sweden)

    Erin K Kuprewicz

    Full Text Available Scatter hoarding of seeds by animals contributes significantly to forest-level processes, including plant recruitment and forest community composition. However, the potential positive and negative effects of caching on seed survival, germination success, and seedling survival have rarely been assessed through experimental studies. Here, I tested the hypothesis that seed burial mimicking caches made by scatter hoarding Central American agoutis (Dasyprocta punctate enhances seed survival, germination, and growth by protecting seeds from seed predators and providing favorable microhabitats for germination. In a series of experiments, I used simulated agouti seed caches to assess how hoarding affects seed predation by ground-dwelling invertebrates and vertebrates for four plant species. I tracked germination and seedling growth of intact and beetle-infested seeds and, using exclosures, monitored the effects of mammals on seedling survival through time. All experiments were conducted over three years in a lowland wet forest in Costa Rica. The majority of hoarded palm seeds escaped predation by both invertebrates and vertebrates while exposed seeds suffered high levels of infestation and removal. Hoarding had no effect on infestation rates of D. panamensis, but burial negatively affected germination success by preventing endocarp dehiscence. Non-infested palm seeds had higher germination success and produced larger seedlings than infested seeds. Seedlings of A. alatum and I. deltoidea suffered high mortality by seed-eating mammals. Hoarding protected most seeds from predators and enhanced germination success (except for D. panamensis and seedling growth, although mammals killed many seedlings of two plant species; all seedling deaths were due to seed removal from the plant base. Using experimental caches, this study shows that scatter hoarding is beneficial to most seeds and may positively affect plant propagation in tropical forests, although

  16. Coevolutionary arms race versus host defense chase in a tropical herbivore-plant system.

    Science.gov (United States)

    Endara, María-José; Coley, Phyllis D; Ghabash, Gabrielle; Nicholls, James A; Dexter, Kyle G; Donoso, David A; Stone, Graham N; Pennington, R Toby; Kursar, Thomas A

    2017-09-05

    Coevolutionary models suggest that herbivores drive diversification and community composition in plants. For herbivores, many questions remain regarding how plant defenses shape host choice and community structure. We addressed these questions using the tree genus Inga and its lepidopteran herbivores in the Amazon. We constructed phylogenies for both plants and insects and quantified host associations and plant defenses. We found that similarity in herbivore assemblages between Inga species was correlated with similarity in defenses. There was no correlation with phylogeny, a result consistent with our observations that the expression of defenses in Inga is independent of phylogeny. Furthermore, host defensive traits explained 40% of herbivore community similarity. Analyses at finer taxonomic scales showed that different lepidopteran clades select hosts based on different defenses, suggesting taxon-specific histories of herbivore-host plant interactions. Finally, we compared the phylogeny and defenses of Inga to phylogenies for the major lepidopteran clades. We found that closely related herbivores fed on Inga with similar defenses rather than on closely related plants. Together, these results suggest that plant defenses might be more evolutionarily labile than the herbivore traits related to host association. Hence, there is an apparent asymmetry in the evolutionary interactions between Inga and its herbivores. Although plants may evolve under selection by herbivores, we hypothesize that herbivores may not show coevolutionary adaptations, but instead "chase" hosts based on the herbivore's own traits at the time that they encounter a new host, a pattern more consistent with resource tracking than with the arms race model of coevolution.

  17. Ant-plant mutualism: a dietary by-product of a tropical ant's macronutrient requirements.

    Science.gov (United States)

    Arcila Hernández, Lina M; Sanders, Jon G; Miller, Gabriel A; Ravenscraft, Alison; Frederickson, Megan E

    2017-12-01

    Many arboreal ants depend on myrmecophytic plants for both food and shelter; in return, these ants defend their host plants against herbivores, which are often insects. Ant-plant and other mutualisms do not necessarily involve the exchange of costly rewards or services; they may instead result from by-product benefits, or positive outcomes that do not entail a cost for one or both partners. Here, we examined whether the plant-ant Allomerus octoarticulatus pays a short-term cost to defend their host plants against herbivores, or whether plant defense is a by-product benefit of ant foraging for insect prey. Because the food offered by ant-plants is usually nitrogen-poor, arboreal ants may balance their diets by consuming insect prey or associating with microbial symbionts to acquire nitrogen, potentially shifting the costs and benefits of plant defense for the ant partner. To determine the effect of ant diet on an ant-plant mutualism, we compared the behavior, morphology, fitness, stable isotope signatures, and gaster microbiomes of A. octoarticulatus ants nesting in Cordia nodosa trees maintained for nearly a year with or without insect herbivores. At the end of the experiment, ants from herbivore exclosures preferred protein-rich baits more than ants in the control (i.e., herbivores present) treatment. Furthermore, workers in the control treatment were heavier than in the herbivore-exclusion treatment, and worker mass predicted reproductive output, suggesting that foraging for insect prey directly increased ant colony fitness. The gaster microbiome of ants was not significantly affected by the herbivore exclusion treatment. We conclude that the defensive behavior of some phytoecious ants is a by-product of their need for external protein sources; thus, the consumption of insect herbivores by ants benefits both the ant colony and the host plant. © 2017 by the Ecological Society of America.

  18. Plant structure predicts leaf litter capture in the tropical montane bromeliad Tillandsia turneri

    Directory of Open Access Journals (Sweden)

    F. Ospina-Bautista

    Full Text Available Abstract Leaves intercepted by bromeliads become an important energy and matter resource for invertebrate communities, bacteria, fungi, and the plant itself. The relationship between bromeliad structure, defined as its size and complexity, and accumulated leaf litter was studied in 55 bromeliads of Tillandsia turneri through multiple regression and the Akaike information criterion. Leaf litter accumulation in bromeliads was best explained by size and complexity variables such as plant cover, sheath length, and leaf number. In conclusion, plant structure determines the amount of litter that enters bromeliads, and changes in its structure could affect important processes within ecosystem functioning or species richness.

  19. Plant structure predicts leaf litter capture in the tropical montane bromeliad Tillandsia turneri.

    Science.gov (United States)

    Ospina-Bautista, F; Estévez Varón, J V

    2016-05-03

    Leaves intercepted by bromeliads become an important energy and matter resource for invertebrate communities, bacteria, fungi, and the plant itself. The relationship between bromeliad structure, defined as its size and complexity, and accumulated leaf litter was studied in 55 bromeliads of Tillandsia turneri through multiple regression and the Akaike information criterion. Leaf litter accumulation in bromeliads was best explained by size and complexity variables such as plant cover, sheath length, and leaf number. In conclusion, plant structure determines the amount of litter that enters bromeliads, and changes in its structure could affect important processes within ecosystem functioning or species richness.

  20. Water relations of woody perennial plant species

    Directory of Open Access Journals (Sweden)

    Kenneth A. Shackel

    2007-09-01

    Significance and impact of study: SWP as a standard method for quantifying water stress in grapevine and other crops will aid research in the development of reliable management practices to improve crop productivity and quality.

  1. Checklist of woody plants of Sulawesi, Indonesia

    NARCIS (Netherlands)

    Keßler, P.J.A.; Bos, M.M.; Sierra Daza, S.E.C.; Kop, A.; Willemse, L.P.M.; Pitopang, R.; Gradstein, S.R.

    2002-01-01

    Sulawesi comprises of about 182,870 km² of land and fewer botanical specimens (about 23 specimens per 100 km², Whitten et al., 1987) have been collected here than in any other major island in Indonesia. This island is up to date botanically poorly explored and according to Van Steenis (1950) about

  2. Water-based woody biorefinery.

    Science.gov (United States)

    Amidon, Thomas E; Liu, Shijie

    2009-01-01

    The conversion of biomass into chemicals and energy is essential in order to sustain our present way of life. Fossil fuels are currently the predominant energy source, but fossil deposits are limited and not renewable. Biomass is a reliable potential source of materials, chemicals and energy that can be replenished to keep pace with our needs. A biorefinery is a concept for the collection of processes used to convert biomass into materials, chemicals and energy. The biorefinery is a "catch and release" method for using carbon that is beneficial to both the environment and the economy. In this study, we discuss three elements of a wood-based biorefinery, as proposed by the SUNY College of Environmental Science and Forestry (ESF): hot-water extraction, hydrolysis, and membrane separation/concentration. Hemicelluloses are the most easily separable main component of woody biomass and thus form the bulk of the extracts obtained by hot-water extraction of woody biomass. Hot-water extraction is an important step in the processes of woody biomass and product generation, replacing alternative costly pre-treatment methods. The hydrolysis of hemicelluloses produces 5-carbon sugars (mainly xylose), 6-carbon sugars (mainly glucose and mannose), and acetic acid. The use of nano-filtration membranes is an efficient technology that can be employed to fractionate hot-water extracts and wood hydrolysate. The residual solid mass after hot-water extraction has a higher energy content and contains fewer easily degradable components. This allows for more efficient subsequent processing to convert cellulose and lignin into conventional products.

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

    Science.gov (United States)

    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

  4. [Native plant resources to optimize the performances of forest rehabilitation in Mediterranean and tropical environment: some examples of nursing plant species that improve the soil mycorrhizal potential].

    Science.gov (United States)

    Duponnois, Robin; Ramanankierana, Heriniaina; Hafidi, Mohamed; Baohanta, Rondro; Baudoin, Ezékiel; Thioulouse, Jean; Sanguin, Hervé; Bâ, Amadou; Galiana, Antoine; Bally, René; Lebrun, Michel; Prin, Yves

    2013-01-01

    The overexploitation of natural resources, resulting in an increased need for arable lands by local populations, causes a serious dysfunction in the soil's biological functioning (mineral deficiency, salt stress, etc.). This dysfunction, worsened by the climatic conditions (drought), requires the implementation of ecological engineering strategies allowing the rehabilitation of degraded areas through the restoration of essential ecological services. The first symptoms of weathering processes of soil quality in tropical and Mediterranean environments result in an alteration of the plant cover structure with, in particular, the pauperization of plant species diversity and abundance. This degradation is accompanied by a weakening of soils and an increase of the impact of erosion on the surface layer resulting in reduced fertility of soils in terms of their physicochemical characteristics as well as their biological ones (e.g., soil microbes). Among the microbial components particularly sensitive to erosion, symbiotic microorganisms (rhizobia, Frankia, mycorrhizal fungi) are known to be key components in the main terrestrial biogeochemical cycles (C, N and P). Many studies have shown the importance of the management of these symbiotic microorganisms in rehabilitation and revegetation strategies of degraded environments, but also in improving the productivity of agrosystems. In particular, the selection of symbionts and their inoculation into the soil were strongly encouraged in recent decades. These inoculants were selected not only for their impact on the plant, but also for their ability to persist in the soil at the expense of the residual native microflora. The performance of this technique was thus evaluated on the plant cover, but its impact on soil microbial characteristics was totally ignored. The role of microbial diversity on productivity and stability (resistance, resilience, etc.) of eco- and agrosystems has been identified relatively recently and has led

  5. ACC deaminase and IAA producing growth promoting bacteria from the rhizosphere soil of tropical rice plants.

    Science.gov (United States)

    Bal, Himadri Bhusan; Das, Subhasis; Dangar, Tushar K; Adhya, Tapan K

    2013-12-01

    Beneficial plant-associated bacteria play a key role in supporting and/or promoting plant growth and health. Plant growth promoting bacteria present in the rhizosphere of crop plants can directly affect plant metabolism or modulate phytohormone production or degradation. We isolated 355 bacteria from the rhizosphere of rice plants grown in the farmers' fields in the coastal rice field soil from five different locations of the Ganjam district of Odisha, India. Six bacteria producing both ACC deaminase (ranging from 603.94 to 1350.02 nmol α-ketobutyrate mg(-1)  h(-1) ) and indole acetic acid (IAA; ranging from 10.54 to 37.65 μM ml(-1) ) in pure cultures were further identified using polyphasic taxonomy including BIOLOG((R)) , FAME analysis and the 16S rRNA gene sequencing. Phylogenetic analyses of the isolates resulted into five major clusters to include members of the genera Bacillus, Microbacterium, Methylophaga, Agromyces, and Paenibacillus. Seed inoculation of rice (cv. Naveen) by the six individual PGPR isolates had a considerable impact on different growth parameters including root elongation that was positively correlated with ACC deaminase activity and IAA production. The cultures also had other plant growth attributes including ammonia production and at least two isolates produced siderophores. Study indicates that presence of diverse rhizobacteria with effective growth-promoting traits, in the rice rhizosphere, may be exploited for a sustainable crop management under field conditions. © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  6. Psidium guajava 'Paluma' (the guava plant) as a new bio-indicator of ozone in the tropics

    Energy Technology Data Exchange (ETDEWEB)

    Furlan, C.M. [Departamento de Botanica, Instituto de Biociencias, Universidade de Sao Paulo, CP 11461, 05422-970 Sao Paulo, SP (Brazil)]. E-mail: furlancm@yahoo.com.br; Moraes, R.M. [Instituto de Botanica, SMA, CP 4005, 01061-970 Sao Paulo (Brazil); Bulbovas, P. [Departamento de Botanica, Instituto de Biociencias, Universidade de Sao Paulo, CP 11461, 05422-970 Sao Paulo, SP (Brazil); Domingos, M. [Instituto de Botanica, SMA, CP 4005, 01061-970 Sao Paulo (Brazil); Salatino, A. [Departamento de Botanica, Instituto de Biociencias, Universidade de Sao Paulo, CP 11461, 05422-970 Sao Paulo, SP (Brazil); Sanz, M.J. [Fundacion Centro de Estudios Ambientales del Mediterraneo, C/C. Darwin, 14, 46980 Paterna, Valencia (Spain)

    2007-06-15

    Psidium guajava 'Paluma' saplings were exposed to carbon filtered air (CF), ambient non-filtered air (NF), and ambient non-filtered air + 40 ppb ozone (NF + O{sub 3}) 8 h per day during two months. The AOT40 values at the end of the experiment were 48, 910 and 12 895 ppb h{sup -1}, respectively for the three treatments. After 5 days of exposure (AOT40 = 1497 ppb h{sup -1}), interveinal red stippling appeared in plants in the NF + O{sub 3} chamber. In the NF chamber, symptoms were observed only after 40 days of exposure (AOT40 = 880 ppb h{sup -1}). After 60 days, injured leaves per plant corresponded to 86% in NF + O{sub 3} and 25% in the NF treatment, and the average leaf area injured was 45% in NF + O{sub 3} and 5% in the NF treatment. The extent of leaf area injured (leaf injury index) was explained mainly by the accumulated exposure of ozone (r {sup 2} = 0.91; p < 0.05). - Psidium guajava 'Paluma', a tropical species widely used in Brazilian food industry, is a potential sensitive bio-indicator of ozone.

  7. Psidium guajava 'Paluma' (the guava plant) as a new bio-indicator of ozone in the tropics

    International Nuclear Information System (INIS)

    Furlan, C.M.; Moraes, R.M.; Bulbovas, P.; Domingos, M.; Salatino, A.; Sanz, M.J.

    2007-01-01

    Psidium guajava 'Paluma' saplings were exposed to carbon filtered air (CF), ambient non-filtered air (NF), and ambient non-filtered air + 40 ppb ozone (NF + O 3 ) 8 h per day during two months. The AOT40 values at the end of the experiment were 48, 910 and 12 895 ppb h -1 , respectively for the three treatments. After 5 days of exposure (AOT40 = 1497 ppb h -1 ), interveinal red stippling appeared in plants in the NF + O 3 chamber. In the NF chamber, symptoms were observed only after 40 days of exposure (AOT40 = 880 ppb h -1 ). After 60 days, injured leaves per plant corresponded to 86% in NF + O 3 and 25% in the NF treatment, and the average leaf area injured was 45% in NF + O 3 and 5% in the NF treatment. The extent of leaf area injured (leaf injury index) was explained mainly by the accumulated exposure of ozone (r 2 = 0.91; p < 0.05). - Psidium guajava 'Paluma', a tropical species widely used in Brazilian food industry, is a potential sensitive bio-indicator of ozone

  8. Calibration of the century, apsim and ndicea models of decomposition and n mineralization of plant residues in the humid tropics

    Directory of Open Access Journals (Sweden)

    Alexandre Ferreira do Nascimento

    2011-06-01

    Full Text Available The aim of this study was to calibrate the CENTURY, APSIM and NDICEA simulation models for estimating decomposition and N mineralization rates of plant organic materials (Arachis pintoi, Calopogonium mucunoides, Stizolobium aterrimum, Stylosanthes guyanensis for 360 days in the Atlantic rainforest bioma of Brazil. The models´ default settings overestimated the decomposition and N-mineralization of plant residues, underlining the fact that the models must be calibrated for use under tropical conditions. For example, the APSIM model simulated the decomposition of the Stizolobium aterrimum and Calopogonium mucunoides residues with an error rate of 37.62 and 48.23 %, respectively, by comparison with the observed data, and was the least accurate model in the absence of calibration. At the default settings, the NDICEA model produced an error rate of 10.46 and 14.46 % and the CENTURY model, 21.42 and 31.84 %, respectively, for Stizolobium aterrimum and Calopogonium mucunoides residue decomposition. After calibration, the models showed a high level of accuracy in estimating decomposition and N- mineralization, with an error rate of less than 20 %. The calibrated NDICEA model showed the highest level of accuracy, followed by the APSIM and CENTURY. All models performed poorly in the first few months of decomposition and N-mineralization, indicating the need of an additional parameter for initial microorganism growth on the residues that would take the effect of leaching due to rainfall into account.

  9. Draft genome sequence of bitter gourd (Momordica charantia), a vegetable and medicinal plant in tropical and subtropical regions.

    Science.gov (United States)

    Urasaki, Naoya; Takagi, Hiroki; Natsume, Satoshi; Uemura, Aiko; Taniai, Naoki; Miyagi, Norimichi; Fukushima, Mai; Suzuki, Shouta; Tarora, Kazuhiko; Tamaki, Moritoshi; Sakamoto, Moriaki; Terauchi, Ryohei; Matsumura, Hideo

    2017-02-01

    Bitter gourd (Momordica charantia) is an important vegetable and medicinal plant in tropical and subtropical regions globally. In this study, the draft genome sequence of a monoecious bitter gourd inbred line, OHB3-1, was analyzed. Through Illumina sequencing and de novo assembly, scaffolds of 285.5 Mb in length were generated, corresponding to ∼84% of the estimated genome size of bitter gourd (339 Mb). In this draft genome sequence, 45,859 protein-coding gene loci were identified, and transposable elements accounted for 15.3% of the whole genome. According to synteny mapping and phylogenetic analysis of conserved genes, bitter gourd was more related to watermelon (Citrullus lanatus) than to cucumber (Cucumis sativus) or melon (C. melo). Using RAD-seq analysis, 1507 marker loci were genotyped in an F2 progeny of two bitter gourd lines, resulting in an improved linkage map, comprising 11 linkage groups. By anchoring RAD tag markers, 255 scaffolds were assigned to the linkage map. Comparative analysis of genome sequences and predicted genes determined that putative trypsin-inhibitor and ribosome-inactivating genes were distinctive in the bitter gourd genome. These genes could characterize the bitter gourd as a medicinal plant. © The Author 2016. Published by Oxford University Press on behalf of Kazusa DNA Research Institute.

  10. Annickia affinis and A. chlorantha (Enantia chlorantha)--A review of two closely related medicinal plants from tropical Africa.

    Science.gov (United States)

    Olivier, D K; Van Vuuren, S F; Moteetee, A N

    2015-12-24

    Annickia affinis (Exell) Versteegh & Sosef, closely related to A. chlorantha Setten & P.J.Maas (both species also referred to as Enantia chlorantha Oliv.), from the Annonaceae family, are multi-purpose medicinal plants used widely across tropical Africa. The two Annickia species are morphologically distinct from each other and have different distribution patterns, but are frequently confused. Furthermore, the name Enantia chlorantha is an illegitimate name, but is still used today. A review of the literature was undertaken and an in-depth analysis of previous research and future prospectives are considered. While a myriad of publications cite the species "Enantia chlorantha", this is not the case for A. affinis and A. chlorantha, and no reviews are available for any of the species to date. Consequently, a summary of their ethnobotany, phytochemistry and biological properties is presented here (for the period 1933 - November 2014) in order to substantiate their traditional importance as medicines for rural people in Africa. To this effect, these species seem to be the preferred traditional treatments for malaria in tropical Africa, an area suffering heavily under the malaria pandemic. Their chemical composition is dominated particularly by various isoquinoline alkaloids, as well as by acetogenins and sesquiterpenes, which have been isolated from the bark and leaves. All three of these classes of compounds have been reported to exhibit noteworthy biological activity. Due to their widespread use, especially of the bark, these species have already been categorized as threatened with extinction. Consequently this study further aims to identify areas where more research needs to be conducted involving these important species, and also to suggest possible means of increasing the biological activities of their extracts as a way to conserve the species. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

  11. Structural breakdown of specialized plant-herbivore interaction networks in tropical forest edges

    Directory of Open Access Journals (Sweden)

    Bruno Ximenes Pinho

    2017-10-01

    Full Text Available Plant-herbivore relationships are essential for ecosystem functioning, typically forming an ecological network with a compartmentalized (i.e. modular structure characterized by highly specialized interactions. Human disturbances can favor habitat generalist species and thus cause the collapse of this modular structure, but its effects are rarely assessed using a network-based approach. We investigate how edge proximity alters plant-insect herbivore networks by comparing forest edge and interior in a large remnant (3.500 ha of the Brazilian Atlantic forest. Given the typical dominance of pioneer plants and generalist herbivores in edge-affected habitats, we test the hypothesis that the specialized structure of plant-herbivore networks collapse in forest edges, resulting in lower modularity and herbivore specialization. Despite no differences in the number of species and interactions, the network structure presented marked differences between forest edges and interior. Herbivore specialization, modularity and number of modules were significantly higher in forest interior than edge-affected habitats. When compared to a random null model, two (22.2% and eight (88.8% networks were significantly modular in forest edge and interior, respectively. The loss of specificity and modularity in plant-herbivore networks in forest edges may be related to the loss of important functions, such as density-dependent control of superior plant competitors, which is ultimately responsible for the maintenance of biodiversity and ecosystem functions. Our results support previous warnings that focusing on traditional community measures only (e.g. species diversity may overlook important modifications in species interactions and ecosystem functioning.

  12. Regional Comparative Advantage for Woody Biofuels Production

    Science.gov (United States)

    Timothy M. Young; Donald G. Hodges; Robert C. Abt; Andy J. Hartsell; James H. Perdue

    2009-01-01

    The economic availability of woody biomass for the southeastern United States is summarized in this final report for the U.S. Department of Transportation, Southeastern Sun Grant Center research contract R11-0515-016 as administered by the University of Tennessee. Georeferenced economic supply curves (marginal cost curves) for woody biomass producers’ for the 13...

  13. Handbook for inventorying downed woody material

    Science.gov (United States)

    James K. Brown

    1974-01-01

    To facilitate debris management, procedures for inventorying downed woody material are presented. Instructions show how to estimate weights and volumes of downed woody material, fuel depth, and duff depth. Using the planar intersect technique, downed material is inventoried by 0- to 0.25-inch, 0.25- to 1-inch, and 1- to 3-inch diameter classes; and by 1-inch classes...

  14. Hydrolysis of Selected Tropical Plant Wastes Catalyzed by a Magnetic Carbonaceous Acid with Microwave

    Science.gov (United States)

    Su, Tong-Chao; Fang, Zhen; Zhang, Fan; Luo, Jia; Li, Xing-Kang

    2015-12-01

    In this study, magnetic carbonaceous acids were synthesized by pyrolysis of the homogeneous mixtures of glucose and magnetic Fe3O4 nanoparticles, and subsequent sulfonation. The synthesis conditions were optimized to obtain a catalyst with both high acid density (0.75 mmol g-1) and strong magnetism [magnetic saturation, Ms = 19.5 Am2 kg-1]. The screened catalyst (C-SO3H/Fe3O4) was used to hydrolyze ball-milled cellulose in a microwave reactor with total reducing sugar (TRS) yield of 25.3% under the best conditions at 190 °C for 3.5 h. It was cycled for at least seven times with high catalyst recovery rate (92.8%), acid density (0.63 mmol g-1) and magnetism (Ms = 12.9 Am2 kg-1), as well as high TRS yield (20.1%) from the hydrolysis of ball-milled cellulose. The catalyst was further successfully tested for the hydrolysis of tropical biomass with high TRS and glucose yields of 79.8% and 58.3% for bagasse, 47.2% and 35.6% for Jatropha hulls, as well as 54.4% and 35.8% for Plukenetia hulls.

  15. Sustainable Biofuels from Forests: Woody Biomass

    Directory of Open Access Journals (Sweden)

    Edwin H. White

    2011-11-01

    Full Text Available The use of woody biomass feedstocks for bioenergy and bioproducts involves multiple sources of material that together create year round supplies. The main sources of woody biomass include residues from wood manufacturing industries, low value trees including logging slash in forests that are currently underutilized and dedicated short-rotation woody crops. Conceptually a ton of woody biomass feedstocks can replace a barrel of oil as the wood is processed (refined through a biorefinery. As oil is refined only part of the barrel is used for liquid fuel, e.g., gasoline, while much of the carbon in oil is refined into higher value chemical products-carbon in woody biomass can be refined into the same value-added products.

  16. Soil fauna and plant litter decomposition in tropical and subalpine forests

    Science.gov (United States)

    G. Gonzalez; T.R. Seastedt

    2001-01-01

    The decomposition of plant residues is influenced by their chemical composition, the physical-chemical environment, and the decomposer organisms. Most studies interested in latitudinal gradients of decomposition have focused on substrate quality and climate effects on decomposition, and have excluded explicit recognition of the soil organisms involved in the process....

  17. Neuroprotection and enhanced neurogenesis by extract from the tropical plant Knema laurina after inflammatory damage in living brain tissue.

    Science.gov (United States)

    Häke, Ines; Schönenberger, Silvia; Neumann, Jens; Franke, Katrin; Paulsen-Merker, Katrin; Reymann, Klaus; Ismail, Ghazally; Bin Din, Laily; Said, Ikram M; Latiff, A; Wessjohann, Ludger; Zipp, Frauke; Ullrich, Oliver

    2009-01-03

    Inflammatory reactions in the CNS, resulting from a loss of control and involving a network of non-neuronal and neuronal cells, are major contributors to the onset and progress of several major neurodegenerative diseases. Therapeutic strategies should therefore keep or restore the well-controlled and finely-tuned balance of immune reactions, and protect neurons from inflammatory damage. In our study, we selected plants of the Malaysian rain forest by an ethnobotanic survey, and investigated them in cell-based-assay-systems and in living brain tissue cultures in order to identify anti-inflammatory and neuroprotective effects. We found that alcoholic extracts from the tropical plant Knema laurina (Black wild nutmeg) exhibited highly anti-inflammatory and neuroprotective effects in cell culture experiments, reduced NO- and IL-6-release from activated microglia cells dose-dependently, and protected living brain tissue from microglia-mediated inflammatory damage at a concentration of 30 microg/ml. On the intracellular level, the extract inhibited ERK-1/2-phosphorylation, IkB-phosphorylation and subsequently NF-kB-translocation in microglia cells. K. laurina belongs to the family of Myristicaceae, which have been used for centuries for treatment of digestive and inflammatory diseases and is also a major food plant of the Giant Hornbill. Moreover, extract from K. laurina promotes also neurogenesis in living brain tissue after oxygen-glucose deprivation. In conclusion, extract from K. laurina not only controls and limits inflammatory reaction after primary neuronal damage, it promotes moreover neurogenesis if given hours until days after stroke-like injury.

  18. Growth and foliar nitrogen concentrations of interplanted native woody legumes and pecan

    Science.gov (United States)

    J.W. Van Sambeek; Nadia E. Navarrete-Tindall; Kenneth L. Hunt

    2008-01-01

    The interplanting and underplanting of nodulated nitrogen-fixing plants in tree plantings can increase early growth and foliage nitrogen content of hardwoods, especially black walnut and pecan. Recent studies have demonstrated that some non-nodulated woody legumes may be capable of fixing significant levels of atmospheric nitrogen. The following nine nurse crop...

  19. Are we filling the data void? An assessment of the amount and extent of plant collection records and census data available for tropical South America.

    Directory of Open Access Journals (Sweden)

    Kenneth Feeley

    Full Text Available Large-scale studies are needed to increase our understanding of how large-scale conservation threats, such as climate change and deforestation, are impacting diverse tropical ecosystems. These types of studies rely fundamentally on access to extensive and representative datasets (i.e., "big data". In this study, I asses the availability of plant species occurrence records through the Global Biodiversity Information Facility (GBIF and the distribution of networked vegetation census plots in tropical South America. I analyze how the amount of available data has changed through time and the consequent changes in taxonomic, spatial, habitat, and climatic representativeness. I show that there are large and growing amounts of data available for tropical South America. Specifically, there are almost 2,000,000 unique geo-referenced collection records representing more than 50,000 species of plants in tropical South America and over 1,500 census plots. However, there is still a gaping "data void" such that many species and many habitats remain so poorly represented in either of the databases as to be functionally invisible for most studies. It is important that we support efforts to increase the availability of data, and the representativeness of these data, so that we can better predict and mitigate the impacts of anthropogenic disturbances.

  20. Evaluation of ash from some tropical plants of Nigeria for the control of Sclerotium rolfsii Sacc. on wheat (Triticum aestivum L.).

    Science.gov (United States)

    Enikuomehin, O A; Ikotun, T; Ekpo, E J

    1998-01-01

    Eleven ash samples, from organs of nine tropical plants, were screened for their abilities to inhibit mycelial growth and sclerotial germination of a Nigerian isolate of Sclerotium rolfsii on agar and in the soil. Ten ash samples showed some activity against mycelial growth of S. rolfsii in vitro. Ash samples from Delonix regia stem wood, Mangifera indica leaf and Vernonia amygdalina leaf were most effective as each totally inhibited mycelial growth of S. rolfsii in vitro. Ocimum gratissimum leaf ash, D. regia wood ash and Musa paradisiaca flower bract ash inhibited sclerotial germination on agar. Nine ash samples protected seeds against pre-emergence rot. Ash from M. indica leaf, V. amygdalina leaf and Azadirachta indica leaf protected seedlings against post-emergence infection. Eichornia crassipes ash, which was ineffective in vitro, offered some protection to seeds in soil against pre-emergence rot. The study demonstrates potentials of ash samples from tropical plants in control of S. rolfsii on wheat.

  1. Species and rotation frequency influence soil nitrogen in simplified tropical plant communities.

    Science.gov (United States)

    Ewel, John J

    2006-04-01

    Among the many factors that potentially influence the rate at which nitrogen (N) becomes available to plants in terrestrial ecosystems are the identity and diversity of species composition, frequency of disturbance or stand turnover, and time. Replicated suites of investigator-designed communities afforded an opportunity to examine the effects of those factors on net N mineralization over a 12-year period. The communities consisted of large-stature perennial plants, comprising three tree species (Hyeronima alchorneoides, Cedrela odorata, and Cordia alliodora), a palm (Euterpe oleracea), and a large, perennial herb (Heliconia imbricata). Trees were grown in monoculture and in combination with the other two life-forms; tree monocultures were subjected to rotations of one or four years, or like the three-life-form systems, left uncut. The work was conducted on fertile soil in the humid lowlands of Costa Rica, a site with few abiotic constraints to plant growth. Rates of net N mineralization and nitrification were high, typically in the range of 0.2-0.8 microg x g(1) x d(-1), with net nitrification slightly higher than net mineralization, indicating preferential uptake of ammonium (NH4+) by plants and microbes. Net rates of N mineralization were about 30% lower in stands of one of the three tree species, Hyeronima, than in stands of the other two. Contrary to expectations, short-rotation management (one or four years) resulted in higher net rates of N mineralization than in uncut stands, whether the latter were composed of a single tree species or a combination of life-forms. Neither additional species richness nor replenishment of leached N augmented mineralization rates. The net rate at which N was supplied tended to be lowest in stands where demand for N was highest. Careful choice of species, coupled with low frequency of disturbance, can lead to maintenance of N within biomass and steady rates of within-system circulation, whereas pulses, whether caused by cutting

  2. Climatological determinants of woody cover in Africa.

    Science.gov (United States)

    Good, Stephen P; Caylor, Kelly K

    2011-03-22

    Determining the factors that influence the distribution of woody vegetation cover and resolving the sensitivity of woody vegetation cover to shifts in environmental forcing are critical steps necessary to predict continental-scale responses of dryland ecosystems to climate change. We use a 6-year satellite data record of fractional woody vegetation cover and an 11-year daily precipitation record to investigate the climatological controls on woody vegetation cover across the African continent. We find that-as opposed to a relationship with only mean annual rainfall-the upper limit of fractional woody vegetation cover is strongly influenced by both the quantity and intensity of rainfall events. Using a set of statistics derived from the seasonal distribution of rainfall, we show that areas with similar seasonal rainfall totals have higher fractional woody cover if the local rainfall climatology consists of frequent, less intense precipitation events. Based on these observations, we develop a generalized response surface between rainfall climatology and maximum woody vegetation cover across the African continent. The normalized local gradient of this response surface is used as an estimator of ecosystem vegetation sensitivity to climatological variation. A comparison between predicted climate sensitivity patterns and observed shifts in both rainfall and vegetation during 2009 reveals both the importance of rainfall climatology in governing how ecosystems respond to interannual fluctuations in climate and the utility of our framework as a means to forecast continental-scale patterns of vegetation shifts in response to future climate change.

  3. Evolutionary persistence in Gunnera and the contribution of southern plant groups to the tropical Andes biodiversity hotspot

    Directory of Open Access Journals (Sweden)

    Christine D. Bacon

    2018-03-01

    Full Text Available Several studies have demonstrated the contribution of northern immigrants to the flora of the tropical Andes—the world’s richest and most diverse biodiversity hotspot. However, much less is known about the biogeographic history and diversification of Andean groups with southern origins, although it has been suggested that northern and southern groups have contributed roughly equally to the high Andean (i.e., páramo flora. Here we infer the evolutionary history of the southern hemisphere plant genus Gunnera, a lineage with a rich fossil history and an important ecological role as an early colonising species characteristic of wet, montane environments. Our results show striking contrasts in species diversification, where some species may have persisted for some 90 million years, and whereas others date to less than 2 Ma since origination. The outstanding longevity of the group is likely linked to a high degree of niche conservatism across its highly disjunct range, whereby Gunnera tracks damp and boggy soils in cool habitats. Colonisation of the northern Andes is related to Quaternary climate change, with subsequent rapid diversification appearing to be driven by their ability to take advantage of environmental opportunities. This study demonstrates the composite origin of a mega-diverse biota.

  4. Does SO{sub 2} fumigation change the chemical defense of woody plants: the effect of short-term SO{sub 2} fumigation on the metabolism of deciduous Salix Myrsinifolia plants

    Energy Technology Data Exchange (ETDEWEB)

    Julkunen-Tiitto, R.; Lavola, A.; Kainulainen, P. [University of Joensuu, Joensuu (Finland). Dept. of Biology

    1995-08-01

    The effect of a moderate increase in atmospheric sulfur dioxide on the production of phenolic secondary chemicals, soluble sugars and phytomass distribution within plants was investigated in six willow ({ital Salix myrsinifolia Salisb}) clones. The plants were cultivated for 3 weeks under 0.11 ppm of SO{sub 2} (300{mu}g m{sup -3}). The production of salicin and chlorogenic acid was significantly reduced under increased SO{sub 2}. However, salicortin, 2{prime}-O-acetylsalicortin, (+)-catechin and two unknown phenolics did not show any clear trend. The increase in SO{sub 2} did not affect the glucose, fructose and sucrose contents. The final weight of the SO{sub 2}-treatment plants was significantly greater than that of the control plants: the leaf, stem and root phytomass was from 14 to 48% greater under increased SO{sub 2}. All the clones showed the same trend, although there was a significant variation in phytomass production. Results indicate, although not consistently, that even a short-term exposure of enhanced atmospheric SO{sub 2} may change moderately the accumulation pattern of willow phenolics. 20 refs., 2 tabs.

  5. Total flavonoids content and biochemical screening of the leaves of tropical endemic medicinal plant Merremia borneensis

    Directory of Open Access Journals (Sweden)

    Muhammad Dawood Shah

    2014-12-01

    Full Text Available The developing and under developed countries mostly rely on traditional medicines. This herbal or traditional medicine involves the use of different types of organic extracts or the bioactive chemical constituents. This type of biochemical investigation provides health care at an affordable cost. This survey such as ethnomedicine keenly represents one of the best avenues in searching new economic plants for medicines. Keeping this view in mind, the present study is carried out in Merremia borneensis leaves of University Malaysia Sabah, Sabah, Malaysia. The plant has several beneficial properties, such as antioxidant activity. The dry powder of the leaves of M. borneensis was extracted with hexane, ethyl acetate, chloroform, butanol and aqueous ethanol. The flavonoids content of the extracts was determined by Willet method. The flavonoids content of the extracts as quercetin equivalents was found to be highest in aqueous ethanol (53.28% followed by chloroform (38.83%, ethyl acetate (24.51%, butanol (12.54% and hexane extract (3.44%. The results suggest the presence of phytochemical properties in the leaves, which are used in curing the ailments.

  6. Effect of Tropical Rotation Crops on Meloidogyne incognita and Other Plant-Parasitic Nematodes.

    Science.gov (United States)

    McSorley, R; Dickson, D W

    1995-12-01

    In a field experiment conducted on sandy soil in Florida during the 1993 season, rotation crops of castor (Ricinus communis), velvetbean (Mucuna deeringina), 'Mississippi Silver' cowpea (Vigna unguiculata), American jointvetch (Aeschynomene americana), 'Dehapine 51' cotton (Gossypium hirsutum), and 'SX-17' sorghum-sudangrass (Sorghum bicolor x S. sudanense) were effective in maintaining low population densities (450/100 cm(3) soil) resulted after 'Clemson Spineless' okra (Hibiscus esculentus) and 'Kirby' soybean (Glycine max). Following a winter cover crop of rye (Secale cereale), densities of M. incognita following the six most effective rotation crops (1993 season) remained relatively low (crop planted in 1994, but increased by the end of the eggplant crop. The rotation crops planted during 1993 had little effect on yield of eggplant in 1994. Eggplant yield was inversely correlated with preplant densities (Pi) of Belonolaimus longicaudatus (r = -0.282; P crop cultivars were lower (P crops intended for suppression of individual Meloidogyne spp. be evaluated for their response to other nematode pests as well.

  7. Financial and energy analyses of woody biomass plantations

    International Nuclear Information System (INIS)

    Strauss, C.H.

    1991-01-01

    This paper provides an economic analysis of a short rotation woody crop (SRWC) plantation system established the financial and energy costs of woody biomass and related net values for the total system. A production model for commercial-sized Populus plantations was developed from a series of research projects sponsored by the U.S,. Department of Energy's Short Rotation Woody Crops Program. The design was based on hybrid poplar planted on good quality agricultural sites at a density of 2100 cutting ha -1 . Growth was forecast at 16 Mg(OD) ha -1 yr -1 on a six-year rotation cycle. All inputs associated with plantation establishment, annual operations, and land use were identified on a financial and energy cost basis (Strauss et al. 1989). Net values for the system projected a minimum financial profit and a major net energy gain. Financial profit was limited by the high market value of energy inputs as compared to the low market value of the energy output. The net energy gain was attributed to the solar energy captured through photosynthesis. Principal input costs to the overall system, on both a financial and energy basis, were land rent and the harvesting/transportation requirements

  8. Taxonomic and phylogenetic diversity of vascular plants at Ma'anling volcano urban park in tropical Haikou, China: Reponses to soil properties.

    Science.gov (United States)

    Cheng, Xia-Lan; Yuan, Lang-Xing; Nizamani, Mir Mohammad; Zhu, Zhi-Xin; Friedman, Cynthia Ross; Wang, Hua-Feng

    2018-01-01

    Anthropogenic processes and socio-economic factors play important roles in shaping plant diversity in urban parks. To investigate how plant diversity of Ma' anling urban volcano park in Hainan Province, China respond to these factors, we carried out a field investigation on the taxonomic and phylogenetic diversity of vascular plants and soil properties in this area. We found 284 species of vascular plants belonging to 88 families and 241 genera, which included 194 native species, 23 invasive species, 31 naturalized species, 40 cultivars, and 4 rare / endangered plant species. Tree composition and richness significantly varied between different vegetation formations (plantation, secondary forest, and abandoned land). Plant species richness and community composition were significantly affected by elevation (El), soil water content (WC), total soil nitrogen (TN) and soil organic matter (SOM). There were significant diversity differences between plantations and abandoned lands, but not between the plantations and secondary forests. The flora in the study site was tropical in nature, characterized by pantropic distributions. Compared to adjacent areas, floristic composition in the study site was most similar to that of Guangdong, followed by that of Vietnam. Our study revealed the diversity patterns of volcanic plants and provided the basis for future planning of plant conservation, such as preserving plant species, maintaining plant habitats, and coordinating plant management in this region.

  9. Root strength of tropical plants - An investigation in the Western Ghats of Kerala, India

    Science.gov (United States)

    Lukose Kuriakose, S.; van Beek, L. P. H.; van Westen, C. J.

    2009-04-01

    Earlier research on debris flows in the Tikovil River basin of the Western Ghats concluded that root cohesion is significant in maintaining the overall stability of the region. In this paper we present the most recent results (December 2008) of root tensile strength tests conducted on nine species of plants that are commonly found in the region. They are 1) Rubber (Hevea Brasiliensis), 2) Coconut Palm (Cocos nucifera), 3) Jackfruit trees (Artocarpus heterophyllus), 4) Teak (Tectona grandis), 5) Mango trees (Mangifera indica), 6) Lemon grass (Cymbopogon citratus), 7) A variety of Tamarind (Garcinia gummigutta), 8) Coffee (Coffea Arabica) and Tea (Camellia sinensis). About 1500 samples were collected of which only 380 could be tested (in the laboratory) due to breakage of roots during the tests. In the successful tests roots failed in tension. Roots having diameters between 2 mm and 12 mm were tested. Each sample tested has a length of 15 cm. Results indicate that the roots of Coffee, Tamarind, Lemon grass and Jackfruit are the strongest of the nine plant types tested whereas Tea and Teak plants had the most fragile roots. Coconut roots behaved atypical to the others, as the bark of the roots was crushed and slipped from the clamp when tested whereas its internal fiber was the strongest of all tested. Root tensile strength decreases with increasing diameters, Rubber showing more ductile behaviour than Coffee and Tamarind that behaved more brittle, root tensile strength increasing exponentially for finer roots. Teak and Tea showed almost a constant root tensile strength over the range of diameters tested and little variability. Jack fruit and mango trees showed the largest variability, which may be explained by the presence of root nodules, preventing the derivation of an unequivocal relationship between root diameters and tensile strength. This results in uncertainty of root strength estimates that are applicable. These results provide important information to

  10. 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.

  11. Exposure-plant response of ambient ozone over the tropical Indian region

    Directory of Open Access Journals (Sweden)

    S. Deb Roy

    2009-07-01

    Full Text Available A high resolution regional chemistry-transport model has been used to study the distribution of exposure-plant response index (AOT40, Accumulated exposure Over a Threshold of 40 ppb, expressed as ppb h over the Indian geographical region for the year 2003 as case study. The directives on ozone pollution in ambient air provided by United Nations Economic Commission for Europe (UNECE and World Health Organization (WHO for vegetation protection (AOT40 have been used to assess the air quality. A substantial temporal and spatial variation in AOT40 values has been observed across the Indian region. Large areas of India show ozone values above the AOT40 threshold limit (3000 ppb h for 3 months. Simulated AOT40 values are found to be substantially higher throughout the year over the most fertile Indo-Gangetic plains than the other regions of India, which can have an adverse effect on plants and vegetation in this region. The observed monthly AOT40 values reported from an Indian station, agree reasonably well with model simulated results. There is an underestimation of AOT40 in the model results during the periods of highest ozone concentration from December to March. We find that the simulated AOT40 target values for protection of vegetation is exceeded even in individual months, especially during November to April. Necessary and effective emission reduction strategies are therefore required to be developed in order to curb the surface level ozone pollution to protect the vegetation from further damage in India whose economy is highly dependent on agricultural sector and may influence the global balance.

  12. Resource potential for renewable energy generation from co-firing of woody biomass with coal in the Northern U.S.

    Science.gov (United States)

    Michael E. Goerndt; Francisco X. Aguilar; Kenneth Skog

    2013-01-01

    Past studies have established measures of co-firing potential at varying spatial scales to assess opportunities for renewable energy generation from woody biomass. This study estimated physical availability, within ecological and public policy constraints, and associated harvesting and delivery costs of woody biomass for co-firing in selected power plants of the...

  13. Acetylation of woody lignocellulose: significance and regulation

    Directory of Open Access Journals (Sweden)

    Prashant Mohan-Anupama Pawar

    2013-05-01

    Full Text Available Non-cellulosic cell wall polysaccharides constitute approximately one quarter of usable biomass for human exploitation. In contrast to cellulose, these components are usually substituted by O-acetyl groups, which affect their properties and interactions with other polymers, thus affecting their solubility and extractability. However, details of these interactions are still largely obscure. Moreover, polysaccharide hydrolysis to constituent monosaccharides, is hampered by the presence of O-acetyl groups, necessitating either enzymatic (esterase or chemical de-acetylation, increasing the costs and chemical consumption. Reduction of polysaccharide acetyl content in planta is a way to modify lignocellulose towards improved saccharification. In this review we: 1 summarize literature on lignocellulose acetylation in different tree species, 2 present data and current hypotheses concerning the role of O-acetylation in determining woody lignocellulose properties, 3 describe plant proteins involved in lignocellulose O-acetylation, 4 give examples of microbial enzymes capable to de-acetylate lignocellulose, and 5 discuss prospects for exploiting these enzymes in planta to modify xylan acetylation.

  14. Water use in four model tropical plant associations established in the lowlands of Costa Rica

    Directory of Open Access Journals (Sweden)

    Marco V Gutiérrez-Soto

    2008-12-01

    Full Text Available We examined soil water use patterns of four model plant associations established in the North Caribbean lowlands of Costa Rica by comparing the stable hydrogen isotope composition, δD, in xylem sap and in soil water at different depths, under rainy and dry conditions. Four 5-year-old model plant associations composed of 2 tree species (Hyeronima alchorneoides and Cedrela odorata having different architecture and phenology were studied. Average tree height was 8.9 and 7.6 m, respectively. Each tree species was grown in monoculture and in polyculture with 2 perennial monocotyledons (Euterpe oleracea and Heliconia imbricata. Maximum rooting depth at the time of δD determination was ~ 2 m for almost all species. Most roots of all species were concentrated in the upper soil layers. Stomatal conductance to water vapor (gS was higher in the deciduous C. odorata than in the evergreen H. alchorneoides; within each species, gS did not differ when the trees were grown in mono or in polyculture. During the rainy season, gradients in soil water δD were not observed. Average rainy season xylem sap δD did not differ among members of the plant combinations tested (-30 ‰, and was more similar to δD values of shallow soil water. Under dry conditions, volumetric soil water content declined from 50 to ~ 35%, and modest gradients in soil water δD were observed. xylem sap δD obtained during dry conditions was significantly lower than rainy season values. xylem sap δD of plants growing in the four associations varied between -9 and -22‰, indicating that shallow water was predominantly absorbed during the dry period too. Differences in xylem sap δD of trees and monocots were also detected, but no significant patterns emerged. The results suggest that: a the plant associations examined extracted water predominantly from shallow soil layers (Examinamos los patrones de uso de agua del suelo de cuatro asociaciones vegetales establecidas en el Caribe norte de

  15. Environmental effects of growing short-rotation woody crops on former agricultural lands

    International Nuclear Information System (INIS)

    Tolbert, V.R.; Thornton, F.C.; Joslin, J.D.

    1997-01-01

    Field-scale studies in the Southeast have been addressing the environmental effects of converting agricultural lands to biomass crop production since 1994. Erosion, surface water quality and quantity and subsurface movement of water and nutrients from woody crops, switchgrass and agricultural crops are being compared. Nutrient cycling, soil physical changes, and crop productivity are also being monitored at the three sites. Maximum sediment losses occurred in the spring and fall. Losses were greater from sweetgum planted without a cover crop than with a cover crop. Nutrient losses of N and P in runoff and subsurface water occurred primarily after spring fertilizer application. These field plot studies are serving as the basis for a water shed study initiated in 1997. Results from the two studies will be used to develop and model nutrient and hydrologic budgets for woody crop plantings to identify potential constraints to sustainable deployment of short-rotation woody crops in the southeastern United States. (author)

  16. Tropical forages: morphoanatomy of plants grown in areas with the death of pasture syndrome

    Directory of Open Access Journals (Sweden)

    N. G. Ribeiro-Júnior

    2017-05-01

    Full Text Available Abstract Roots and leaves of Panicum maximum Tanzânia, Mombaça and Massai; Urochloa brizantha Piatã, Marandu and Xaraés; Urochloa humidicola Llanero; Urochloa ruziziensis Ruzizienses; Urochloa hybrida Mulato II and Cynodon nlemfuensis Estrela-roxa were analyzed, seeking to identify characters for better adaptation to the environment that may interfere with digestibility of tissue from the point of view of the rumen in cattle. Were planted ten cultivars in a completely randomized blocks with three repetitions. Was collected vegetative material, which histological slides were prepared from middle third of the sections of roots and leaves. Were observed differences (p>0.05 in the roots: higher volume of epidermal cells (28.62 µm and overall diameter (1926.41 µm of Llanero; thicker vascular cylinder (975.09 µm and more protoxylem (42.25 in Estrela-roxa and occurrence of aerenchyma in cultivars Piatã, Mulato II, Xaraés, Massai, Llanero and Estrela-roxa; Were found higher proportions of bulliform cells in the leaves (121.07 µm and thicker leaf mesophyll in U. humidicola Llanero (263.63 µm; higher proportion of sclerenchyma fibers in Xaraés and Marandu; lower results for amount of fibers in P. maximum Massai. We conclude that the cultivars Estrela-roxa, Llanero and Massai have greater adaptability to the environment and better nutritional quality.

  17. Future challenges for woody biomass projections

    NARCIS (Netherlands)

    Schadauer, K.; Barreiro, Susana; Schelhaas, M.; McRoberts, Ronald E.

    2017-01-01

    Many drivers affect woody biomass projections including forest available for wood supply, market behavior, forest ownership, distributions by age and yield classes, forest typologies resulting from different edaphic, climatic conditions, and last but not least, how these factors are incorporated

  18. Determinants of woody cover in African savannas

    Science.gov (United States)

    Sankaran, M.; Hanan, N.P.; Scholes, Robert J.; Ratnam, J.; Augustine, D.J.; Cade, B.S.; Gignoux, J.; Higgins, S.I.; Le, Roux X.; Ludwig, F.; Ardo, J.; Banyikwa, F.; Bronn, A.; Bucini, G.; Caylor, K.K.; Coughenour, M.B.; Diouf, A.; Ekaya, W.; Feral, C.J.; February, E.C.; Frost, P.G.H.; Hiernaux, P.; Hrabar, H.; Metzger, K.L.; Prins, H.H.T.; Ringrose, S.; Sea, W.; Tews, J.; Worden, J.; Zambatis, N.

    2005-01-01

    Savannas are globally important ecosystems of great significance to human economies. In these biomes, which are characterized by the co-dominance of trees and grasses, woody cover is a chief determinant of ecosystem properties 1-3. The availability of resources (water, nutrients) and disturbance regimes (fire, herbivory) are thought to be important in regulating woody cover1,2,4,5, but perceptions differ on which of these are the primary drivers of savanna structure. Here we show, using data from 854 sites across Africa, that maximum woody cover in savannas receiving a mean annual precipitation (MAP) of less than ???650 mm is constrained by, and increases linearly with, MAP. These arid and semi-arid savannas may be considered 'stable' systems in which water constrains woody cover and permits grasses to coexist, while fire, herbivory and soil properties interact to reduce woody cover below the MAP-controlled upper bound. Above a MAP of ???650 mm, savannas are 'unstable' systems in which MAP is sufficient for woody canopy closure, and disturbances (fire, herbivory) are required for the coexistence of trees and grass. These results provide insights into the nature of African savannas and suggest that future changes in precipitation 6 may considerably affect their distribution and dynamics. ?? 2005 Nature Publishing Group.

  19. Determination of soil-to-plant transfer factors of {sup 137}Cs and {sup 90}Sr in the tropical environment of Bangladesh

    Energy Technology Data Exchange (ETDEWEB)

    Mollah, A.S.; Begum, A. [Atomic Energy Research Establishment (AERE), Savar, Dacca (Bangladesh); Ullah, S.M. [University of Dhaka (Bangladesh). Department of Soil Science

    1998-07-01

    Soil-to-plant transfer factors (TF) of {sup 137}Cs and {sup 90}Sr have been determined for different plants/crops, such as rice, beans, peanuts, pineapple, cabbage, tomato, spinach and grass. They were obtained from radioisotope experiments on plants grown in pots under outdoor ambient tropical conditions for three growing seasons (1994-1996). In the case of {sup 137}Cs and concerning the above mentioned plants/crops, the average TFs were found to be 0.28, 0.25, 0.77, 0.19, 0.23, 0.28, 0.59 and 0.18, respectively. In the case of {sup 90}Sr, the average TFs were found to be 0.82, 0.51, 0.20, 0.82, 0.69, 0.59, 0.91 and 0.84, respectively. A minor seasonal variation was observed. This study provides a database of TFs for tropical environments to be used, e.g., for radiological safety assessment models. (orig.) With 1 fig., 3 tabs., 12 refs.

  20. Woody biomass energy potential in 2050

    International Nuclear Information System (INIS)

    Lauri, Pekka; Havlík, Petr; Kindermann, Georg; Forsell, Nicklas; Böttcher, Hannes; Obersteiner, Michael

    2014-01-01

    From a biophysical perspective, woody biomass resources are large enough to cover a substantial share of the world's primary energy consumption in 2050. However, these resources have alternative uses and their accessibility is limited, which tends to decrease their competitiveness with respect to other forms of energy. Hence, the key question of woody biomass use for energy is not the amount of resources, but rather their price. In this study we consider the question from the perspective of energy wood supply curves, which display the available amount of woody biomass for large-scale energy production at various hypothetical energy wood prices. These curves are estimated by the Global Biosphere Management Model (GLOBIOM), which is a global partial equilibrium model of forest and agricultural sectors. The global energy wood supply is estimated to be 0–23 Gm 3 /year (0–165 EJ/year) when energy wood prices vary in a range of 0–30$/GJ (0–216$/m 3 ). If we add household fuelwood to energy wood, then woody biomass could satisfy 2–18% of world primary energy consumption in 2050. If primary forests are excluded from wood supply then the potential decreases up to 25%. - highlights: • We examine woody biomass energy potential by partial equilibrium model of forest and agriculture sectors. • It is possible to satisfy 18% (or 14% if primary forests are excluded) of the world's primary energy consumption in 2050 by woody biomass. • To achieve this would require an extensive subsidy/tax policy and would lead to substantial higher woody biomass prices compared to their current level

  1. Floristic indicators of tropical landuse systems: Evidence from mining areas in Southwestern Nigeria

    Directory of Open Access Journals (Sweden)

    Sehinde Akinbiola

    2016-07-01

    Full Text Available Most forests in the tropics have not only been reduced in size but have also experienced forest degradation. The delicate balance of the components of the forest ecosystem has been altered largely by the landuse systems which have resulted in the disappearance of some species and the introduction of new ones. In order to understand the influence of human disturbance caused by artisanal mining on plant biodiversity and the physical environment, this study assessed changes in vegetation characteristics using plant functional groups, such as invasive, pioneer and understory species. The study was conducted at two sites in two Southwestern states of Nigeria, Itagunmodi in Atakumosa West Local Government Area of Osun State and Olode in Oluyole Local Government Area of Oyo State. Complete enumerations of woody, non-woody and herbaceous plant species were carried out in 20 m by 20 m plots selected using stratified random sampling as representative of landuse classes: freshly mined (6 months and a control plot (secondary forest. The results showed that the control plot in Itagunmodi had undergone degradation as indicated by the presence of Alchornea laxiflora, Geophilia obvallata, Musa sapientum,Elaeis guineensis and Keetia hispida. However, if left undisturbed, it has the potential of regeneration back to its original state because of its woody tree species composition and lianas (Triclisia gilletii. In addition the forest soils in the mines had been exposed to direct insolation for a long period, and the soil structure and texture have been affected, consequently altering the viability of the seed bank. Poaceae and Papilionoideae were the most common in the freshly mined plots while invasive species were the most common in abandoned mined plots. In conclusion, the floristic composition in the mining sites has been altered and there was no clear evidence that regrowth would bring restoration of the lost ecosystem services.

  2. A Computer-Based Simulation for Teaching Heat Transfer across a Woody Stem

    Science.gov (United States)

    Maixner, Michael R.; Noyd, Robert K.; Krueger, Jerome A.

    2010-01-01

    To assist student understanding of heat transfer through woody stems, we developed an instructional package that included an Excel-based, one-dimensional simulation model and a companion instructional worksheet. Guiding undergraduate botany students to applying principles of thermodynamics to plants in nature is fraught with two main obstacles:…

  3. Water-use strategies of six co-existing Mediterranean woody species during a summer drought

    NARCIS (Netherlands)

    Quero, J.L.; Sterck, F.J.; Martínez-Vilalta, J.; Villar, R.

    2011-01-01

    Drought stress is known to limit plant performance in Mediterranean-type ecosystems. We have investigated the dynamics of the hydraulics, gas exchange and morphology of six co-existing Mediterranean woody species growing under natural field conditions during a drought that continued during the

  4. Trophic ecology of Lepidoptera larvae associated with woody vegetation in a savanna ecosystem

    CSIR Research Space (South Africa)

    Scholtz, CH

    1982-06-01

    Full Text Available This study represents a quantitative survey of a Lepidoptera community and deals with the trophic ecology of the 27 species of foliage-feeding Lepidoptera on the eight dominant woody plants in the Burkea africana-Eragrostis pallens savanna...

  5. Status of exotic woody species in big cypress national preserve. Technical report

    Energy Technology Data Exchange (ETDEWEB)

    Gunderson, L.H.

    1983-12-01

    The current status of exotic woody plants in Big Cypress National Preserve is documented. A map of the distribution of principal pest species, Melaleuca quinquenervia, Schinus terebinthifolius, and Casuarina sp., is presented. Prognoses of population increases of these problem species are determined utilizing the current distributions and assessing environmental conditions. Some potential problem species are also identified.

  6. Spatial Modeling of Industrial Windfall on Soils to Detect Woody Species with Potential for Bioremediation

    Science.gov (United States)

    S. Salazar; M. Mendoza; A. M. Tejeda

    2006-01-01

    A spatial model is presented to explain the concentration of heavy metals (Fe, Cu, Zn, Ni, Cr, Co and Pb), in the soils around the industrial complex near the Port of Veracruz, Mexico. Unexpected low concentration sites where then tested to detect woody plant species that may have the capability to hiperacumulate these contaminants, hence having a potential for...

  7. Final report on a field study of soil-to-plant transfer radioactive caesium, strontium and zinc in Tropical Northern Australia

    International Nuclear Information System (INIS)

    Twining, J.; Payne, T.; Russell, R.; Wilde, K; McOrist, G.; Wong, H.; Shotton, P.; Tagami, K.; Itakura, T.

    2003-01-01

    Soil-to-plant radionuclide transfer factors for cesium ( 134 Cs), strontium ( 85 Sr) and zinc ( 65 Zn) into sorghum and mung plants grown in tropical Australia have been determined over a four-year study period. The crops were grown on two types of red earth soils. Transfer factors for Cs and Sr are not substantially different from the expected values based on previous studies, reported in the general literature and compiled in the IUR database, mainly performed within temperate climates. In contrast, the values for zinc (Zn) are more than an order of magnitude greater than anticipated. Most of the radioactivity added to the soils has been retained in the top 5 cm of both soils. There has been a general decline in soil-to-plant transfer of Cs and Zn as time has increased

  8. The spatial pattern and dominant drivers of woody cover change in Latin America and Caribbean from 2001 to 2010

    Science.gov (United States)

    Clark, M.; Aide, T.; Riner, G.; Redo, D.; Grau, H.; Bonilla-Moheno, M.; Lopez-Carr, D.; Levy, M.

    2011-12-01

    Change in woody vegetation (i.e., forests, shrublands) is a major component of global environmental change: it directly affects biodiversity, the global carbon budget, and ecosystem function. For several decades, remote sensing technology has been used to document deforestation in Latin America and the Caribbean (LAC), although mostly at local to regional scales (e.g., moist forests of the Amazon basin). Most studies have focused on forest loss, some local-scale studies have mapped forest recovery, with contrasting forest dynamics attributed to shifting demographic and socio-economic factors. For example, local population change (rural-urban migration) can stimulate forest recovery on abandoned land, while increasing global food demand may drive regional expansion of mechanized agriculture. However, there are no studies in LAC that simultaneously map both loss and gain in woody vegetation at continental, national, and municipality scales with consistent data sources, methods and accuracy; and thus, we lack a comprehensive assessment of the spatial distribution of woody vegetation change and the relative importance of the multi-scale drivers of this change. We overcame this limitation by producing annual land-cover maps between 2001 and 2010 for each of the >16,000 municipalities in LAC. We focused on mapping municipality-scale trends in three broad classes: woody vegetation, mixed woody/plantations, and agriculture/herbaceous vegetation. Our area estimates show that woody vegetation change during the past decade was dominated by deforestation, or loss (-541,830 km2), particularly in the Amazon basin moist forest and the tropical-subtropical Cerrado and Chaco ecoregions, where large swaths of forest have been transformed to pastures and agricultural lands. Extensive areas (362,431 km2) in LAC also gained woody vegetation, particularly in regions too dry or too steep for modern agriculture, including the desert/xeric shrub biome in NE Brazil and northern Mexico, the

  9. Spatial partitioning of water use by herbaceous and woody lifeforms in semiarid woodlands

    International Nuclear Information System (INIS)

    Breshears, D.D.

    1993-01-01

    Ecological studies of soil moisture, plant water uptake, and community composition in semiarid regions have focused on differences with depth in the soil profile, yet there are many reasons to expect that moisture also varies with the presence or absence of woody vegetation. Plant and soil moisture relationships for three dominant species in a semiarid woodland, Bouteloua gracilis, Juniperus monosperma, and Pinus edulis, were studied for 1.5 years. Soil moisture varied by type of plant cover as well as by depth. Plant water potential and conductance differed among species and was related to spatial variability in soil moisture. Water potential for blue grama was most correlated with soil moisture in the 0-15 cm layer of intercanopies; juniper water potential was highly correlated with soil moisture in the 0-15 cm layer beneath tree canopies of either species, and pinyon water potential was only weakly correlated with soil moisture in the 15-30 cm depth interval beneath pinyons. Pinyons had consistently greater maximum conductance rates than junipers, even though pinyon conductance was more sensitive to reductions in soil moisture. The results from this study indicate that horizontal differences in the soil moisture profile associated with type of plant cover may be as important as differences in depth for predicting plant-water relationships. A simple model was hypothesized for predicting community composition of three lifeforms: Herbaceous plants, shallow-rooted woody plants, and deeper-rooted woody plants. Distributions of roots of each lifeform and plant-available water were defined with respect to four soil compartments that distinguish upper vs. lower and canopy vs. intercanopy soil regions. The model predicts that multiple combinations of herbaceous and woody biomass can exist at a site and was qualitatively consistent with field data from a climatic gradient

  10. Isotopes in tropical agriculture

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1962-04-15

    Ways in which the use of radioisotopes and radiation can help to improve the agriculture of tropical Africa were discussed by a panel of experts. The panel included scientists from Africa, Europe, and the United States, most of whom had had actual experience dealing with agricultural problems in various parts of tropical Africa. The experts agreed that radioisotopes and radiation might now be employed to particular advantage in tropical Africa to improve crop nutrition and combat insect pests. Other applications discussed were in the fields of hydrology, plant breeding and food preservation

  11. Isotopes in tropical agriculture

    International Nuclear Information System (INIS)

    1962-01-01

    Ways in which the use of radioisotopes and radiation can help to improve the agriculture of tropical Africa were discussed by a panel of experts. The panel included scientists from Africa, Europe, and the United States, most of whom had had actual experience dealing with agricultural problems in various parts of tropical Africa. The experts agreed that radioisotopes and radiation might now be employed to particular advantage in tropical Africa to improve crop nutrition and combat insect pests. Other applications discussed were in the fields of hydrology, plant breeding and food preservation

  12. Flowering of Woody Bamboo in Tissue Culture Systems

    Directory of Open Access Journals (Sweden)

    Jin-Ling Yuan

    2017-09-01

    Full Text Available Flowering and subsequent seed set are not only normal activities in the life of most plants, but constitute the very reason for their existence. Woody bamboos can take a long time to flower, even over 100 years. This makes it difficult to breed bamboo, since flowering time cannot be predicted and passing through each generation takes too long. Another unique characteristic of woody bamboo is that a bamboo stand will often flower synchronously, both disrupting the supply chain within the bamboo industry and affecting local ecology. Therefore, an understanding of the mechanism that initiates bamboo flowering is important not only for biology research, but also for the bamboo industry. Induction of flowering in vitro is an effective way to both shorten the flowering period and control the flowering time, and has been shown for several species of bamboo. The use of controlled tissue culture systems allows investigation into the mechanism of bamboo flowering and facilitates selective breeding. Here, after a brief introduction of flowering in bamboo, we review the research on in vitro flowering of bamboo, including our current understanding of the effects of plant growth regulators and medium components on flower induction and how in vitro bamboo flowers can be used in research.

  13. [Historical research of cinchona cultivation in Japan (Part 2). Useful tropical plants introduced from Java and India in the early Meiji era].

    Science.gov (United States)

    Nagumo, Seiji; Sasaki, Yohei; Takido, Michio

    2010-01-01

    In the early Meiji era, Takeaki Enomoto made a proposal to the government that cinchona and coffee seedlings be introduced to Japan. In response, the Meiji government dispatched Masatsugu Takeda of the Ministry of Internal Affairs to Java and India from March to August 1878 for the purpose of investigating useful plants of tropical origin and introducing them to Japan. This paper clarifies the route to those destinations and the plants obtained locally. Using the seeds obtained from India during his travels, the cultivation of cinchona was attempted in 1882 for the first time in Japan. In Ogasawara, coffee cultivation was conducted, again for the first time in Japan, using coffee seeds brought back from Java. The cultivation of coffee was successful and served as the foundation of the Ogasawara coffee that exists to this day. Takeda also introduced a number of books and materials related to useful tropical plants available as a result of his travels, which contributed to the promotion of new industries and businesses in the Meiji era.

  14. Lianas and trees in tropical forests in south China

    NARCIS (Netherlands)

    Cai, Z.Q.

    2007-01-01

    Lianas (woody climbers) and trees are the most important life-forms in most tropical forests. In many of these forests lianas are abundant and diverse and their presence is often a key physiognomic feature. Lianas contribute substantially to the floristic, structural and functional diversity of

  15. Intraspecific leaf trait variability along a boreal-to-tropical community diversity gradient

    Science.gov (United States)

    Bastias, Cristina C.; Fortunel, Claire; Valladares, Fernando; Baraloto, Christopher; Benavides, Raquel; Cornwell, William; Markesteijn, Lars; de Oliveira, Alexandre A.; Sansevero, Jeronimo B. B.; Vaz, Marcel C.; Kraft, Nathan J. B.

    2017-01-01

    Disentangling the mechanisms that shape community assembly across diversity gradients is a central matter in ecology. While many studies have explored community assembly through species average trait values, there is a growing understanding that intraspecific trait variation (ITV) can also play a critical role in species coexistence. Classic biodiversity theory hypothesizes that higher diversity at species-rich sites can arise from narrower niches relative to species-poor sites, which would be reflected in reduced ITV as species richness increases. To explore how ITV in woody plant communities changes with species richness, we compiled leaf trait data (leaf size and specific leaf area) in a total of 521 woody plant species from 21 forest communities that differed dramatically in species richness, ranging from boreal to tropical rainforests. At each forest, we assessed ITV as an estimate of species niche breadth and we quantified the degree of trait overlap among co-occurring species as a measure of species functional similarity. We found ITV was relatively invariant across the species richness gradient. In addition, we found that species functional similarity increased with diversity. Contrary to the expectation from classic biodiversity theory, our results rather suggest that neutral processes or equalizing mechanisms can be acting as potential drivers shaping community assembly in hyperdiverse forests. PMID:28241033

  16. Closed Loop Short Rotation Woody Biomass Energy Crops

    Energy Technology Data Exchange (ETDEWEB)

    Brower, Michael [CRC Development, LLC, Oakland, CA (United States)

    2012-09-30

    CRC Development LLC is pursuing commercialization of shrub willow crops to evaluate and confirm estimates of yield, harvesting, transportation and renewable energy conversion costs and to provide a diverse resource in its supply portfolio.The goal of Closed Loop Short Rotation Woody Biomass Energy Crops is supply expansion in Central New York to facilitate the commercialization of willow biomass crops as part of the mix of woody biomass feedstocks for bioenergy and bioproducts. CRC Development LLC established the first commercial willow biomass plantation acreage in North America was established on the Tug Hill in the spring of 2006 and expanded in 2007. This was the first 230- acres toward the goal of 10,000 regional acres. This project replaces some 2007-drought damaged acreage and installs a total of 630-acre new planting acres in order to demonstrate to regional agricultural producers and rural land-owners the economic vitality of closed loop short rotation woody biomass energy crops when deployed commercially in order to motivate new grower entry into the market-place. The willow biomass will directly help stabilize the fuel supply for the Lyonsdale Biomass facility, which produces 19 MWe of power and exports 15,000 pph of process steam to Burrows Paper. This project will also provide feedstock to The Biorefinery in New York for the manufacture of renewable, CO2-neutral liquid transportation fuels, chemicals and polymers. This project helps end dependency on imported fossil fuels, adds to region economic and environmental vitality and contributes to national security through improved energy independence.

  17. Knowledge of the Yucatec Maya in seasonal tropical forest management: the forage plants El conocimiento de los mayas yucatecos en el manejo del bosque tropical estacional: las plantas forrajeras

    Directory of Open Access Journals (Sweden)

    José Salvador Flores

    2012-06-01

    Full Text Available Indigenous knowledge and the millenary experience in management of natural vegetation on karstic landscapes are important aspects that should be considered in animal production in seasonal tropical environments. The aim of the present work was to make an inventory of native plants associated to soilscapes from seasonal tropical forests from the Yucatán Peninsula that are used as forage by Mayan people. The work was carried out in 27 Mayan communities on karst landscapes in the Yucatán Peninsula as a part of the "Ethnoflora Yucatanense" project of the Universidad Autónoma de Yucatán. Samples were taken of forage plants together with corresponding floristic and ethnobotanical information. Data were processed in EXCEL dynamic tables, grouped by plant family, geoforms and soils, life form and animal consumers. Results indicate that Mayan communities use 196 plant species as forage: 139 herbaceous, 17 shrubs, 35 trees and 2 palms. These plants are fed to cows, pigs, horses, lambs, turkeys, chickens, ducks and pigeons. The use of native forage plants may be an agricultural option both for rural communities and for intensive animal production on silvopastoral systems on karstic tropical landscapes from the Yucatán Peninsula.El conocimiento indígena y la experiencia de milenios de años en el manejo de la vegetación natural en ambientes kársticos tropicales son aspectos importantes que deben ser considerados en la producción animal. El objetivo de este trabajo fue hacer un inventario de las plantas forrajeras nativas de los bosques tropicales estacionales de la península de Yucatán que son utilizadas por los mayas, incluyendo los paisajes edáficos en los que se encuentran las plantas, información que servirá de base para la planeación de las actividades agropecuarias. El trabajo se llevó al cabo en 27 comunidades indígenas mayas, como parte del proyecto "Etnoflora Yucatanense" de la Universidad Autónoma de Yucatán. Las muestras de

  18. Assessing Woody Vegetation Trends in Sahelian Drylands Using MODIS Based Seasonal Metrics

    Science.gov (United States)

    Brandt, Martin; Hiernaux, Pierre; Rasmussen, Kjeld; Mbow, Cheikh; Kergoat, Laurent; Tagesson, Torbern; Ibrahim, Yahaya Z.; Wele, Abdoulaye; Tucker, Compton J.; Fensholt, Rasmus

    2016-01-01

    Woody plants play a major role for the resilience of drylands and in peoples' livelihoods. However, due to their scattered distribution, quantifying and monitoring woody cover over space and time is challenging. We develop a phenology driven model and train/validate MODIS (MCD43A4, 500m) derived metrics with 178 ground observations from Niger, Senegal and Mali to estimate woody cover trends from 2000 to 2014 over the entire Sahel. The annual woody cover estimation at 500 m scale is fairly accurate with an RMSE of 4.3 (woody cover %) and r(exp 2) = 0.74. Over the 15 year period we observed an average increase of 1.7 (+/- 5.0) woody cover (%) with large spatial differences: No clear change can be observed in densely populated areas (0.2 +/- 4.2), whereas a positive change is seen in sparsely populated areas (2.1 +/- 5.2). Woody cover is generally stable in cropland areas (0.9 +/- 4.6), reflecting the protective management of parkland trees by the farmers. Positive changes are observed in savannas (2.5 +/- 5.4) and woodland areas (3.9 +/- 7.3). The major pattern of woody cover change reveals strong increases in the sparsely populated Sahel zones of eastern Senegal, western Mali and central Chad, but a decreasing trend is observed in the densely populated western parts of Senegal, northern Nigeria, Sudan and southwestern Niger. This decrease is often local and limited to woodlands, being an indication of ongoing expansion of cultivated areas and selective logging.We show that an overall positive trend is found in areas of low anthropogenic pressure demonstrating the potential of these ecosystems to provide services such as carbon storage, if not over-utilized. Taken together, our results provide an unprecedented synthesis of woody cover dynamics in theSahel, and point to land use and human population density as important drivers, however only partially and locally offsetting a general post-drought increase.

  19. The influence of woody encroachment on the nitrogen cycle: fixation, storage and gas loss

    Science.gov (United States)

    Soper, F.; Sparks, J. P.

    2015-12-01

    Woody encroachment is a pervasive land cover change throughout the tropics and subtropics. Encroachment is frequently catalyzed by nitrogen (N)-fixing trees and the resulting N inputs potentially alter whole-ecosystem N cycling, accumulation and loss. In the southern US, widespread encroachment by legume Prosopis glandulosa is associated with increased soil total N storage, inorganic N concentrations, and net mineralization and nitrification rates. To better understand the effects of this process on ecosystem N cycling, we investigated patterns of symbiotic N fixation, N accrual and soil N trace gas and N2 emissions during Prosopis encroachment into the southern Rio Grande Plains. Analyses of d15N in foliage, xylem sap and plant-available soil N suggested that N fixation rates increase with tree age and are influenced by abiotic conditions. A model of soil N accrual around individual trees, accounting for atmospheric inputs and gas losses, generates lifetimes N fixation estimates of up to 9 kg for a 100-year-old tree and current rates of 7 kg N ha-1 yr-1. However, these N inputs and increased soil cycling rates do not translate into increased N gas losses. Two years of field measurements of a complete suite of N trace gases (ammonia, nitrous oxide, nitric oxide and other oxidized N compounds) found no difference in flux between upland Prosopis groves and adjacent unencroached grasslands. Total emissions for both land cover types average 0.56-0.65 kg N ha-1 yr-1, comparable to other southern US grasslands. Additional lab experiments suggested that N2 losses are low and that field oxygen conditions are not usually conducive to denitrification. Taken together, results suggest that this ecosystem is currently experiencing a period of net N accrual under ongoing encroachment.

  20. Effects of competition and herbivory over woody seedling growth in a temperate woodland trump the effects of elevated CO2.

    Science.gov (United States)

    Collins, L; Boer, M M; de Dios, V Resco; Power, S A; Bendall, E R; Hasegawa, S; Hueso, R Ochoa; Nevado, J Piñeiro; Bradstock, R A

    2018-04-27

    A trend of increasing woody plant density, or woody thickening, has been observed across grassland and woodland ecosystems globally. It has been proposed that increasing atmospheric [CO 2 ] is a major driver of broad scale woody thickening, though few field-based experiments have tested this hypothesis. Our study utilises a Free Air CO 2 Enrichment experiment to examine the effect of elevated [CO 2 ] (eCO 2 ) on three mechanisms that can cause woody thickening, namely (i) woody plant recruitment, (ii) seedling growth, and (iii) post-disturbance resprouting. The study took place in a eucalypt-dominated temperate grassy woodland. Annual assessments show that juvenile woody plant recruitment occurred over the first 3 years of CO 2 fumigation, though eCO 2 did not affect rates of recruitment. Manipulative experiments were established to examine the effect of eCO 2 on above-ground seedling growth using transplanted Eucalyptus tereticornis (Myrtaceae) and Hakea sericea (Proteaceae) seedlings. There was no positive effect of eCO 2 on biomass of either species following 12 months of exposure to treatments. Lignotubers (i.e., resprouting organs) of harvested E. tereticornis seedlings that were retained in situ for an additional year were used to examine resprouting response. The likelihood of resprouting and biomass of resprouts increased with lignotuber volume, which was not itself affected by eCO 2 . The presence of herbaceous competitors and defoliation by invertebrates and pathogens were found to greatly reduce growth and/or resprouting response of seedlings. Our findings do not support the hypothesis that future increases in atmospheric [CO 2 ] will, by itself, promote woody plant recruitment in eucalypt-dominated temperate grassy woodlands.

  1. Treatment of high-strength wastewater in tropical constructed wetlands planted with Sesbania sesban: Horizontal subsurface flow versus vertical downflow

    DEFF Research Database (Denmark)

    Dan, Truong Hoang; Quang, Le Nhat; Chiem, Nguyen Huu

    2011-01-01

    Treatment of various types of wastewaters is an urgent problem in densely populated areas of many tropical countries. We studied the potential of using Sesbania sesban, an N2-fixing shrub, in constructed wetland systems for the treatment of high-strength wastewater. A replicated horizontal subsur...

  2. The Eucalyptus grandis R2R3-MYB transcription factor family: evidence for woody growth-related evolution and function.

    Science.gov (United States)

    Soler, Marçal; Camargo, Eduardo Leal Oliveira; Carocha, Victor; Cassan-Wang, Hua; San Clemente, Hélène; Savelli, Bruno; Hefer, Charles A; Paiva, Jorge A Pinto; Myburg, Alexander A; Grima-Pettenati, Jacqueline

    2015-06-01

    The R2R3-MYB family, one of the largest transcription factor families in higher plants, controls a wide variety of plant-specific processes including, notably, phenylpropanoid metabolism and secondary cell wall formation. We performed a genome-wide analysis of this superfamily in Eucalyptus, one of the most planted hardwood trees world-wide. A total of 141 predicted R2R3-MYB sequences identified in the Eucalyptus grandis genome sequence were subjected to comparative phylogenetic analyses with Arabidopsis thaliana, Oryza sativa, Populus trichocarpa and Vitis vinifera. We analysed features such as gene structure, conserved motifs and genome location. Transcript abundance patterns were assessed by RNAseq and validated by high-throughput quantitative PCR. We found some R2R3-MYB subgroups with expanded membership in E. grandis, V. vinifera and P. trichocarpa, and others preferentially found in woody species, suggesting diversification of specific functions in woody plants. By contrast, subgroups containing key genes regulating lignin biosynthesis and secondary cell wall formation are more conserved across all of the species analysed. In Eucalyptus, R2R3-MYB tandem gene duplications seem to disproportionately affect woody-preferential and woody-expanded subgroups. Interestingly, some of the genes belonging to woody-preferential subgroups show higher expression in the cambial region, suggesting a putative role in the regulation of secondary growth. © 2014 The Authors New Phytologist © 2014 New Phytologist Trust.

  3. Fire and climate suitability for woody vegetation communities in the south central United States

    Science.gov (United States)

    Stroh, Esther; Struckhoff, Matthew; Stambaugh, Michael C.; Guyette, Richard P.

    2018-01-01

    Climate and fire are primary drivers of plant species distributions. Long-term management of south central United States woody vegetation communities can benefit from information on potential changes in climate and fire frequencies, and how these changes might affect plant communities. We used historical (1900 to 1929) and future (2040 to 2069 and 2070 to 2099) projected climate data for the conterminous US to estimate reference and future fire probabilities

  4. Tropical Rainforests.

    Science.gov (United States)

    Nigh, Ronald B.; Nations, James D.

    1980-01-01

    Presented is a summary of scientific knowledge about the rainforest environment, a tropical ecosystem in danger of extermination. Topics include the current state of tropical rainforests, the causes of rainforest destruction, and alternatives of rainforest destruction. (BT)

  5. Emissions of biogenic volatile organic compounds and subsequent photochemical production of secondary organic aerosol in mesocosm studies of temperate and tropical plant species

    Science.gov (United States)

    Wyche, K. P.; Ryan, A. C.; Hewitt, C. N.; Alfarra, M. R.; McFiggans, G.; Carr, T.; Monks, P. S.; Smallbone, K. L.; Capes, G.; Hamilton, J. F.; Pugh, T. A. M.; MacKenzie, A. R.

    2014-12-01

    Silver birch (Betula pendula) and three Southeast Asian tropical plant species (Ficus cyathistipula, Ficus benjamina and Caryota millis) from the pantropical fig and palm genera were grown in a purpose-built and environment-controlled whole-tree chamber. The volatile organic compounds emitted from these trees were characterised and fed into a linked photochemical reaction chamber where they underwent photo-oxidation under a range of controlled conditions (relative humidity or RH ~65-89%, volatile organic compound-to-NOx or VOC / NOx ~3-9 and NOx ~2 ppbV). Both the gas phase and the aerosol phase of the reaction chamber were monitored in detail using a comprehensive suite of on-line and off-line chemical and physical measurement techniques. Silver birch was found to be a high monoterpene and sesquiterpene but low isoprene emitter, and its emissions were observed to produce measurable amounts of secondary organic aerosol (SOA) via both nucleation and condensation onto pre-existing seed aerosol (YSOA 26-39%). In contrast, all three tropical species were found to be high isoprene emitters with trace emissions of monoterpenes and sesquiterpenes. In tropical plant experiments without seed aerosol there was no measurable SOA nucleation, but aerosol mass was shown to increase when seed aerosol was present. Although principally isoprene emitting, the aerosol mass produced from tropical fig was mostly consistent (i.e. in 78 out of 120 aerosol mass calculations using plausible parameter sets of various precursor specific yields) with condensation of photo-oxidation products of the minor volatile organic compounds (VOCs) co-emitted; no significant aerosol yield from condensation of isoprene oxidation products was required in the interpretations of the experimental results. This finding is in line with previous reports of organic aerosol loadings consistent with production from minor biogenic VOCs co-emitted with isoprene in principally isoprene-emitting landscapes in Southeast

  6. 48 CFR 1452.237-71 - Utilization of Woody Biomass.

    Science.gov (United States)

    2010-10-01

    ... Biomass. 1452.237-71 Section 1452.237-71 Federal Acquisition Regulations System DEPARTMENT OF THE INTERIOR... Utilization of Woody Biomass. As prescribed in § 1437.7202, insert the following clause: Utilization of Woody Biomass (MAY 2005) (a) The contractor may remove and utilize woody biomass, if: (1) Project work is...

  7. Determinants of patchiness of woody vegetation in an African savanna

    NARCIS (Netherlands)

    Veldhuis, Michiel P.; Rozen-Rechels, David; le Roux, Elizabeth; Cromsigt, Joris P.G.M.; Berg, Matheus P.; Olff, Han

    2016-01-01

    How is woody vegetation patchiness affected by rainfall, fire and large herbivore biomass? Can we predict woody patchiness and cover over large-scale environmental gradients? We quantified variation in local patchiness as the lacunarity of woody cover on satellite-derived images. Using Random Forest

  8. Global variability in leaf respiration in relation to climate, plant functional types and leaf traits.

    Science.gov (United States)

    Atkin, Owen K; Bloomfield, Keith J; Reich, Peter B; Tjoelker, Mark G; Asner, Gregory P; Bonal, Damien; Bönisch, Gerhard; Bradford, Matt G; Cernusak, Lucas A; Cosio, Eric G; Creek, Danielle; Crous, Kristine Y; Domingues, Tomas F; Dukes, Jeffrey S; Egerton, John J G; Evans, John R; Farquhar, Graham D; Fyllas, Nikolaos M; Gauthier, Paul P G; Gloor, Emanuel; Gimeno, Teresa E; Griffin, Kevin L; Guerrieri, Rossella; Heskel, Mary A; Huntingford, Chris; Ishida, Françoise Yoko; Kattge, Jens; Lambers, Hans; Liddell, Michael J; Lloyd, Jon; Lusk, Christopher H; Martin, Roberta E; Maksimov, Ayal P; Maximov, Trofim C; Malhi, Yadvinder; Medlyn, Belinda E; Meir, Patrick; Mercado, Lina M; Mirotchnick, Nicholas; Ng, Desmond; Niinemets, Ülo; O'Sullivan, Odhran S; Phillips, Oliver L; Poorter, Lourens; Poot, Pieter; Prentice, I Colin; Salinas, Norma; Rowland, Lucy M; Ryan, Michael G; Sitch, Stephen; Slot, Martijn; Smith, Nicholas G; Turnbull, Matthew H; VanderWel, Mark C; Valladares, Fernando; Veneklaas, Erik J; Weerasinghe, Lasantha K; Wirth, Christian; Wright, Ian J; Wythers, Kirk R; Xiang, Jen; Xiang, Shuang; Zaragoza-Castells, Joana

    2015-04-01

    Leaf dark respiration (Rdark ) is an important yet poorly quantified component of the global carbon cycle. Given this, we analyzed a new global database of Rdark and associated leaf traits. Data for 899 species were compiled from 100 sites (from the Arctic to the tropics). Several woody and nonwoody plant functional types (PFTs) were represented. Mixed-effects models were used to disentangle sources of variation in Rdark . Area-based Rdark at the prevailing average daily growth temperature (T) of each site increased only twofold from the Arctic to the tropics, despite a 20°C increase in growing T (8-28°C). By contrast, Rdark at a standard T (25°C, Rdark (25) ) was threefold higher in the Arctic than in the tropics, and twofold higher at arid than at mesic sites. Species and PFTs at cold sites exhibited higher Rdark (25) at a given photosynthetic capacity (Vcmax (25) ) or leaf nitrogen concentration ([N]) than species at warmer sites. Rdark (25) values at any given Vcmax (25) or [N] were higher in herbs than in woody plants. The results highlight variation in Rdark among species and across global gradients in T and aridity. In addition to their ecological significance, the results provide a framework for improving representation of Rdark in terrestrial biosphere models (TBMs) and associated land-surface components of Earth system models (ESMs). © 2015 The Authors. New Phytologist © 2015 New Phytologist Trust.

  9. Influence of Removal of a Non-native Tree Species Mimosa caesalpiniifolia Benth. on the Regenerating Plant Communities in a Tropical Semideciduous Forest Under Restoration in Brazil

    Science.gov (United States)

    Podadera, Diego S.; Engel, Vera L.; Parrotta, John A.; Machado, Deivid L.; Sato, Luciane M.; Durigan, Giselda

    2015-11-01

    Exotic species are used to trigger facilitation in restoration plantings, but this positive effect may not be permanent and these species may have negative effects later on. Since such species can provide a marketable product (firewood), their harvest may represent an advantageous strategy to achieve both ecological and economic benefits. In this study, we looked at the effect of removal of a non-native tree species ( Mimosa caesalpiniifolia) on the understory of a semideciduous forest undergoing restoration. We assessed two 14-year-old plantation systems (modified "taungya" agroforestry system; and mixed plantation using commercial timber and firewood tree species) established at two sites with contrasting soil properties in São Paulo state, Brazil. The experimental design included randomized blocks with split plots. The natural regeneration of woody species (height ≥0.2 m) was compared between managed (all M. caesalpiniifolia trees removed) and unmanaged plots during the first year after the intervention. The removal of M. caesalpiniifolia increased species diversity but decreased stand basal area. Nevertheless, the basal area loss was recovered after 1 year. The management treatment affected tree species regeneration differently between species groups. The results of this study suggest that removal of M. caesalpiniifolia benefited the understory and possibly accelerated the succession process. Further monitoring studies are needed to evaluate the longer term effects on stand structure and composition. The lack of negative effects of tree removal on the natural regeneration indicates that such interventions can be recommended, especially considering the expectations of economic revenues from tree harvesting in restoration plantings.

  10. Spatial modeling of potential woody biomass flow

    Science.gov (United States)

    Woodam Chung; Nathaniel Anderson

    2012-01-01

    The flow of woody biomass to end users is determined by economic factors, especially the amount available across a landscape and delivery costs of bioenergy facilities. The objective of this study develop methodology to quantify landscape-level stocks and potential biomass flows using the currently available spatial database road network analysis tool. We applied this...

  11. Community patterns of tropical tree phenology derived from Unmanned Aerial Vehicle images: intra- and interspecific variation, association with species plant traits, and response to interannual climate variation

    Science.gov (United States)

    Bohlman, Stephanie; Rifai, Sami; Park, John; Dandois, Jonathan; Muller-Landau, Helene

    2017-04-01

    Phenology is a key life history trait of plant species and critical driver of ecosystem processes. There is strong evidence that phenology is shifting in temperate ecosystems in response to climate change, but tropical forest phenology remains poorly quantified and understood. A key challenge is that tropical forests contain hundreds of plant species with a wide variety of phenological patterns, which makes it difficult to collect sufficient ground-based field data to characterize individual tropical tree species phenologies. Satellite-based observations, an important source of phenology data in northern latitudes, are hindered by frequent cloud cover in the tropics. To quantify phenology over a large number of individuals and species, we collected bi-weekly images from unmanned aerial vehicles (UAVs) in the well-studied 50-ha forest inventory plot on Barro Colorado Island, Panama. The objective of this study is to quantify inter- and intra-specific responses of tropical tree leaf phenology to environmental variation over large spatial scales and identify key environmental variables and physiological mechanisms underpinning phenological variation. Between October 2014 and December 2015 and again in May 2015, we collected a total of 35 sets of UAV images, each with continuous coverage of the 50-ha plot, where every tree ≥ 1 cm DBH is mapped. UAV imagery was corrected for exposure, orthorectified, and then processed to extract spectral, texture, and image information for individual tree crowns, which was then used as inputs for a machine learning algorithm that successfully predicted the percentages of leaf, branch, and flower cover for each tree crown (r2=0.76 between observed and predicted percent branch cover for individual tree crowns). We then quantified cumulative annual deciduousness for each crown by fitting a non-parametric curve of flexible shape to its predicted percent branch time series and calculated the area under the curve. We obtained the species

  12. Expected international demand for woody and herbaceous feedstock

    Energy Technology Data Exchange (ETDEWEB)

    Lamers, Patrick [Idaho National Lab. (INL), Idaho Falls, ID (United States); Jacobson, Jacob [Idaho National Lab. (INL), Idaho Falls, ID (United States); Mohammad, Roni [Idaho National Lab. (INL), Idaho Falls, ID (United States); Wright, Christopher [Idaho National Lab. (INL), Idaho Falls, ID (United States)

    2015-03-01

    The development of a U.S. bioenergy market and ultimately ‘bioeconomy’ has primarily been investigated with a national focus. Limited attention has been given to the potential impacts of international market developments. The goal of this project is to advance the current State of Technology of a single biorefinery to the global level providing quantitative estimates on how international markets may influence the domestic feedstock supply costs. The scope of the project is limited to feedstock that is currently available and new crops being developed to be used in a future U.S. bioeconomy including herbaceous residues (e.g., corn stover), woody biomass (e.g., pulpwood), and energy crops (e.g., switchgrass). The timeframe is set to the periods of 2022, 2030, and 2040 to align with current policy targets (e.g., the RFS2) and future updates of the Billion Ton data. This particular milestone delivers demand volumes for generic woody and herbaceous feedstocks for the main (net) importing regions along the above timeframes. The regional focus of the study is the European Union (EU), currently the largest demand region for U.S. pellets made from pulpwood and forest residues. The pellets are predominantly used in large-scale power plants (>5MWel) in the United Kingdom (UK), the Netherlands (NL), Belgium (BE), and Denmark (DK).

  13. Assessment of Plant Functional Types in Tropical Arid and Semi-Arid Ecosystems of India Using Remote Sensing Data and GIS

    Science.gov (United States)

    Sudhakar Reddy, C.; Krishna, P. Hari; Murthy, M. S. R.

    2011-09-01

    Tropica