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Sample records for evergreen nothofagus species

  1. Seasonal changes in the photosynthetic performance of two evergreen Nothofagus species in south central Chile Cambios estacionales en el desempeño fotosintético de dos especies siempreverdes de Nothofagus en el centro sur de Chile

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    RAFAEL ZÚÑIGA

    2006-12-01

    Full Text Available The evergreen Nothofagus dombeyi and Nothofagus nitida are important members of the temperate Chilean rainforest. They seldom grow together in nature. Nothofagus nitida is more susceptible to excess light and drought than N. dombeyi. We postulate that the different properties of the photosynthetic apparatus under common garden conditions of these species could explain their contrasting habitat preferences. The two species growing in a common garden in south central Chile were studied. The optimal photochemical efficiency (Fv/Fm of both species remained within normal values (»0.8 with the exception of a decrease in N. dombeyi at midday in summer, suggesting reversible reduction in photochemical efficiency of photosystem II (PSII. During summer the effective photochemical efficiency (F PSII, photochemical quenching (qP, photosynthesis (Amax, stomatal conductance (gs and transpiration rates (E in N. dombeyi were higher than in N. nitida. The highest increments in photoprotective pigments (zeaxanthin + antheraxanthin and lutein contents between predawn and midday were obtained in summer in N. dombeyi. In N. nitida a nocturnal retention of dissipative pigments, without a decrease in Fv/Fm, was found in winter. The results suggest that N. dombeyi showed a better photosynthetic performance than N. nitida under high light, high temperature, and drier conditions. These data support are consistent with the pioneer character of N. dombeyi and the semi-tolerant shade properties and more restricted distribution of N. nitida. These photosynthetic characteristics, along with their freezing and flooding resistance differences, may result from their habitat separationLas siempreverdes, Nothofagus dombeyi y Nothofagus nitida, representantes importantes de los bosques lluviosos templados de Chile, raramente crecen juntos en forma natural. Nothofagus nitida es más sensible al exceso de luz y déficit de agua que N. dombeyi. Se postula que diferentes propiedades

  2. Similar variation in carbon storage between deciduous and evergreen treeline species across elevational gradients.

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    Fajardo, Alex; Piper, Frida I; Hoch, Günter

    2013-08-01

    The most plausible explanation for treeline formation so far is provided by the growth limitation hypothesis (GLH), which proposes that carbon sinks are more restricted by low temperatures than by carbon sources. Evidence supporting the GLH has been strong in evergreen, but less and weaker in deciduous treeline species. Here a test is made of the GLH in deciduous-evergreen mixed species forests across elevational gradients, with the hypothesis that deciduous treeline species show a different carbon storage trend from that shown by evergreen species across elevations. Tree growth and concentrations of non-structural carbohydrates (NSCs) in foliage, branch sapwood and stem sapwood tissues were measured at four elevations in six deciduous-evergreen treeline ecotones (including treeline) in the southern Andes of Chile (40°S, Nothofagus pumilio and Nothofagus betuloides; 46°S, Nothofagus pumilio and Pinus sylvestris) and in the Swiss Alps (46°N, Larix decidua and Pinus cembra). Tree growth (basal area increment) decreased with elevation for all species. Regardless of foliar habit, NSCs did not deplete across elevations, indicating no shortage of carbon storage in any of the investigated tissues. Rather, NSCs increased significantly with elevation in leaves (P treeline species are sink limited when faced with decreasing temperatures. Despite the overall higher requirements of deciduous tree species for carbon storage, no indication was found of carbon limitation in deciduous species in the alpine treeline ecotone.

  3. Tree size and light availability increase photochemical instead of non-photochemical capacities of Nothofagus nitida trees growing in an evergreen temperate rain forest.

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    Coopman, Rafael E; Briceño, Verónica F; Corcuera, Luis J; Reyes-Díaz, Marjorie; Alvarez, Daniela; Sáez, Katherine; García-Plazaola, José I; Alberdi, Miren; Bravo, León A

    2011-10-01

    Nothofagus nitida (Phil.) Krasser (Nothofagaceae) regenerates under the canopy in microsites protected from high light. Nonetheless, it is common to find older saplings in clear areas and adults as emergent trees of the Chilean evergreen forest. We hypothesized that this shade to sun transition in N. nitida is supported by an increase in photochemical and non-photochemical energy dissipation capacities of both photosystems in parallel with the increase in plant size and light availability. To dissect the relative contribution of light environment and plant developmental stage to these physiological responses, the photosynthetic performance of both photosystems was studied from the morpho-anatomical to the biochemical level in current-year leaves of N. nitida plants of different heights (ranging from 0.1 to 7 m) growing under contrasting light environments (integrated quantum flux (IQF) 5-40 mol m(-2). Tree height (TH) and light environment (IQF) independently increased the saturated electron transport rates of both photosystems, as well as leaf and palisade thickness, but non-photochemical energy flux, photoinhibition susceptibility, state transition capacity, and the contents of D1 and PsbS proteins were not affected by IQF and TH. Spongy mesophyll thickness and palisade cell diameter decreased with IQF and TH. A(max), light compensation and saturation points, Rubisco and nitrogen content (area basis) only increased with light environment (IQF), whereas dark respiration (R(d)) decreased slightly and relative chlorophyll content was higher in taller trees. Overall, the independent effects of more illuminated environment and tree height mainly increased the photochemical instead of the non-photochemical energy flux. Regardless of the photochemical increase with TH, carbon assimilation only significantly improved with higher IQF. Therefore it seems that mainly acclimation to the light environment supports the phenotypic transition of N. nitida from shade to

  4. Distribución natural de Nothofagus alpina y Nothofagus obliqua (nothofagaceae en Argentina, dos especies de primera importancia forestal de los bosques templados norpatagónicos Natural distribution of Nothofagus alpina and Nothofagus obliqua (Nothofagaceae in Argentina, two productively important tree species of the North Patagonian temperate forests

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    Yamila Sabatier

    2011-06-01

    Full Text Available Conocer la distribución natural de cualquier especie es esencial para poder planificar su conservación o uso. El Raulí [Nothofagus alpina (Poepp. & Endl. Oerst. = Nothofagus nervosa (Phil. Dim. et Mil.] y el Roble Pellín [Nothofagus obliqua (Mirb. Oerst. ssp. obliqua] son dos especies forestales de primera importancia en los bosques norpatagónicos, y objetos de un programa de domesticación en curso. En base al cruce de capas de información digital de estudios previos verificada por informantes locales calificados, por controles de campo y por interpretación sobre pantalla de imágenes provistas libremente por Google Earth, se mapeó la distribución natural de ambas especies en Argentina. La presencia del Raulí se registra sobre una superficie de 79.636 ha, mientras que sobre 33.859 ha se desarrollan bosques con presencia de Roble Pellín. La mayor parte de estas superficies se encuentran protegidas por el sistema de Parques Nacionales (97 % del área ocupada con Raulí y 83 % de la ocupada con Roble Pellín, sin embargo varios bosques relevantes para la conservación se hallan bajo jurisdicción de la Provincia de Neuquén, lo cual debería ser considerado al momento de planear una estrategia de conservación para ambas especies.Knowing the natural range of any species is essential to plan its conservation or use. The South-American beeches Raulí [Nothofagus alpina (Poepp. & Endl. Oerst. = Nothofagus nervosa (Phil. Dim. et Mil.] and Roble Pellín [Nothofagus obliqua (Mirb. Oerst. ssp. obliqua] are two important forest tree species of the North Patagonian forests, and the object of a current domestication program. Natural distribution of both beeches in Argentina was mapped based on digital information of previous works which was verified by local qualified informants, ground control check and visual interpretation of images freely provided by Google Earth. Raulí is present over a surface of 79,636 ha, while 33,859 ha are occupied by

  5. Are trait-scaling relationships invariant across contrasting elevations in the widely distributed treeline species Nothofagus pumilio?

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    Fajardo, Alex

    2016-05-01

    The study of scaling examines the relative dimensions of diverse organismal traits. Understanding whether global scaling patterns are paralleled within species is key to identify causal factors of universal scaling. I examined whether the foliage-stem (Corner's rules), the leaf size-number, and the leaf mass-leaf area scaling relationships remained invariant and isometric with elevation in a wide-distributed treeline species in the southern Chilean Andes. Mean leaf area, leaf mass, leafing intensity, and twig cross-sectional area were determined for 1-2 twigs of 8-15 Nothofagus pumilio individuals across four elevations (including treeline elevation) and four locations (from central Chile at 36°S to Tierra del Fuego at 54°S). Mixed effects models were fitted to test whether the interaction term between traits and elevation was nonsignificant (invariant). The leaf-twig cross-sectional area and the leaf mass-leaf area scaling relationships were isometric (slope = 1) and remained invariant with elevation, whereas the leaf size-number (i.e., leafing intensity) scaling was allometric (slope ≠ -1) and showed no variation with elevation. Leaf area and leaf number were consistently negatively correlated across elevation. The scaling relationships examined in the current study parallel those seen across species. It is plausible that the explanation of intraspecific scaling relationships, as trait combinations favored by natural selection, is the same as those invoked to explain across species patterns. Thus, it is very likely that the global interspecific Corner's rules and other leaf-leaf scaling relationships emerge as the aggregate of largely parallel intraspecific patterns. © 2016 Botanical Society of America.

  6. A comparison of {sup 137}Cs radioactivity in localized evergreen and deciduous plant species

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    Rangel, R.C.

    1996-05-01

    A vegetation study at the Comanche Peak Steam Electric Station (CPSES) near Glen Rose, Texas was conducted in 1991 and 1992. The CPSES is a commercial nuclear power plant owned and operated by Texas Utilities Electric of Dallas, Texas. The US Nuclear Regulatory Commission (USNRC) requires the CPSES to routinely sample broadleaf vegetation in place of milk samples. Few commercial dairies exist in the vicinity. Broadleaf tree species are scarce because the climate and local limestone geology have produced a dry rolling hill topography. An evergreen juniper is the dominant tree species. Few broadleaves during the winter season have hindered year-round sampling. This study compares the environmental {sup 137}Cs concentrations between broadleaf and evergreen foliage at CPSES. Soil {sup 137}Cs concentrations from each vegetation location were also compared to the foliage {sup 137}Cs concentrations. The study`s objective was to determine if the deciduous and evergreen vegetation {sup 137}Cs concentrations are statistically the same.

  7. Resource partitioning by evergreen and deciduous species in a tropical dry forest.

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    Álvarez-Yépiz, Juan C; Búrquez, Alberto; Martínez-Yrízar, Angelina; Teece, Mark; Yépez, Enrico A; Dovciak, Martin

    2017-02-01

    Niche differentiation can lead to coexistence of plant species by partitioning limiting resources. Light partitioning promotes niche differentiation in tropical humid forests, but it is unclear how niche partitioning occurs in tropical dry forests where both light and soil resources can be limiting. We studied the adult niche of four dominant evergreen (cycad, palm) and drought-deciduous (legume, oak) species co-occurring along environmental gradients. We analyzed light intensity and soil fertility effects on key functional traits related to plant carbon and water economy, how these traits determine species' functional strategies, and how these strategies relate to relative species abundance and spatial patterns. Light intensity was negatively associated with a key trait linked to plant water economy (leaf δ 13 C, a proxy for long-term water-use efficiency-WUE), while soil fertility was negatively associated with a key trait for plant carbon economy (LNC, leaf nitrogen content). Evergreens were highly sclerophyllous and displayed an efficient water economy but poor carbon economy, in agreement with a conservative resource-use strategy (i.e., high WUE but low LNC, photosynthetic rates and stature). Conversely, deciduous species, with an efficient carbon economy but poor water economy, exhibited an exploitative resource-use strategy (i.e., high LNC, photosynthetic rates and stature, but low WUE). Evergreen and deciduous species segregated spatially, particularly at fine-scales, as expected for species with different resource-use strategies. The efficient water economy of evergreens was related to their higher relative abundance, suggesting a functional advantage against drought-deciduous species in water-limited environments within seasonally dry tropical forests.

  8. Whole-plant allocation to storage and defense in juveniles of related evergreen and deciduous shrub species.

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    Wyka, T P; Karolewski, P; Żytkowiak, R; Chmielarz, P; Oleksyn, J

    2016-05-01

    In evergreen plants, old leaves may contribute photosynthate to initiation of shoot growth in the spring. They might also function as storage sites for carbohydrates and nitrogen (N). We hence hypothesized that whole-plant allocation of carbohydrates and N to storage in stems and roots may be lower in evergreen than in deciduous species. We selected three species pairs consisting of an evergreen and a related deciduous species: Mahonia aquifolium (Pursh) Nutt. and Berberis vulgaris L. (Berberidaceae), Prunus laurocerasus L. and Prunus serotina Ehrh. (Rosaceae), and Viburnum rhytidophyllum Hemsl. and Viburnum lantana L. (Adoxaceae). Seedlings were grown outdoors in pots and harvested on two dates during the growing season for the determination of biomass, carbohydrate and N allocation ratios. Plant size-adjusted pools of nonstructural carbohydrates in stems and roots were lower in the evergreen species of Berberidaceae and Adoxaceae, and the slope of the carbohydrate pool vs plant biomass relationship was lower in the evergreen species of Rosaceae compared with the respective deciduous species, consistent with the leading hypothesis. Pools of N in stems and roots, however, did not vary with leaf habit. In all species, foliage contained more than half of the plant's nonstructural carbohydrate pool and, in late summer, also more than half of the plant's N pool, suggesting that in juvenile individuals of evergreen species, leaves may be a major storage site. Additionally, we hypothesized that concentration of defensive phenolic compounds in leaves should be higher in evergreen than in deciduous species, because the lower carbohydrate pool in stems and roots of the former restricts their capacity for regrowth following herbivory and also because of the need to protect their longer-living foliage. Our results did not support this hypothesis, suggesting that evergreen plants may rely predominantly on structural defenses. In summary, our study indicates that leaf habit has

  9. Propagation of Native Tree Species to Restore Subtropical Evergreen Broad-Leaved Forests in SW China

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    Yang Lu

    2016-01-01

    Full Text Available Subtropical evergreen broad-leaved forest (EBLF is a widespread vegetation type throughout East Asia that has suffered extensive deforestation and fragmentation. Selection and successful propagation of native tree species are important for improving ecological restoration of these forests. We carried out a series of experiments to study the propagation requirements of indigenous subtropical tree species in Southwest China. Seeds of 21 tree species collected from the natural forest were materials for the experiment. This paper examines the seed germination and seedling growth performance of these species in a nursery environment. Germination percentages ranged from 41% to 96% and were ≥50% for 19 species. The median length of germination time (MLG ranged from 24 days for Padus wilsonii to 144 days for Ilex polyneura. Fifteen species can reach the transplant size (≥15 cm in height within 12 months of seed collection. Nursery-grown seedlings for each species were planted in degraded site. Two years after planting, the seedling survival rate was >50% in 18 species and >80% in 12 species. Based on these results, 17 species were recommended as appropriate species for nursery production in forest restoration projects. Our study contributes additional knowledge regarding the propagation techniques for various native subtropical tree species in nurseries for forest restoration.

  10. Responses of evergreen and deciduous Quercus species to enhanced ozone levels

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    Calatayud, Vicent, E-mail: calatayud_viclor@gva.e [Instituto Universitario CEAM-UMH, Charles R. Darwin 14, Parc Tecnologic, 46980 Paterna, Valencia (Spain); Cervero, Julia; Calvo, Esperanza [Instituto Universitario CEAM-UMH, Charles R. Darwin 14, Parc Tecnologic, 46980 Paterna, Valencia (Spain); Garcia-Breijo, Francisco-Jose [Laboratorio de Anatomia e Histologia Vegetal ' Julio Iranzo' , Jardin Botanico, Universitat de Valencia, c/Quart 80, 46008 Valencia (Spain); Departamento de Ecosistemas Agroforestales, Escuela Tecnica Superior del Medio Rural y Enologia, Universidad Politecnica de Valencia, Avda. Blasco Ibanez 21, 46010 Valencia (Spain); Reig-Arminana, Jose [Departamento de Ecosistemas Agroforestales, Escuela Tecnica Superior del Medio Rural y Enologia, Universidad Politecnica de Valencia, Avda. Blasco Ibanez 21, 46010 Valencia (Spain); Sanz, Maria Jose [Instituto Universitario CEAM-UMH, Charles R. Darwin 14, Parc Tecnologic, 46980 Paterna, Valencia (Spain)

    2011-01-15

    Plants of one evergreen oak (Quercus ilex) and three deciduous oaks (Q. faginea, with small leaves; Q. pyrenaica and Q. robur, with large leaves) were exposed both to filtered air and to enhanced ozone levels in Open-Top Chambers. Q. faginea and Q. pyrenaica were studied for the first time. Based on visible injury, gas exchange, chlorophyll content and biomass responses, Q. pyrenaica was the most sensitive species, and Q. ilex was the most tolerant, followed by Q. faginea. Functional leaf traits of the species were related to differences in sensitivity, while accumulated ozone flux via stomata (POD{sub 1.6}) partly contributed to the observed differences. For risk assessment of Mediterranean vegetation, the diversity of responses detected in this study should be taken into account, applying appropriate critical levels. - Ozone tolerance overlapped with leaf traits in four Quercus species.

  11. Seasonal patterns of reflectance indices, carotenoid pigments and photosynthesis of evergreen chaparral species.

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    Stylinski, C; Gamon, J; Oechel, W

    2002-05-01

    This study examined the ability of the Photochemical Reflectance Index (PRI) to track seasonal variations in carotenoid pigments and photosynthetic activity of mature evergreen chaparral shrubs. Our results confirm that PRI scales with photosystem two (PSII) photochemical efficiency across species and seasons, as demonstrated by PRI's strong correlation with de-epoxidized (photoprotective) xanthophyll cycle pigment levels (normalized to chlorophyll) and with the chlorophyll fluorescence index, ΔF/Fm'. PRI and carotenoid pigment levels (de-epoxidized xanthophyll cycle pigments normalized to chlorophyll or total carotenoid pigments normalized to chlorophyll) were correlated with seasonal fluctuations in midday net CO2 uptake of top-canopy leaves. By contrast, chlorophyll levels (as measured by the Chlorophyll Index) were not as strongly linked to photosynthetic activity, particularly when all species were considered together. Likewise, the Normalized Difference Vegetation Index (NDVI, an index of canopy greenness) did not correlate with net CO2 uptake. Canopy NDVI also did not correlate with canopy PRI, demonstrating that these indices were largely independent over the temporal and spatial scales of this study. Together, these patterns provide evidence for coordinated regulation of carotenoid pigments, PSII electron transport, and carboxylation across seasons and indicate that physiological adjustments are more important than structural ones in modifying CO2-fixation capacity during periods of photosynthetic down-regulation for these evergreen species. The strong correlation between PRI of whole canopies and PRI of top-canopy leaves suggests that the canopy can be treated as a "big leaf" in terms of this reflectance index and that PRI can be used in "scalable" models. This along with the links between carotenoid pigments, PSII photochemical efficiency and carboxylation across species and seasons supports the use of optical assays of pigment levels and PSII activity

  12. Relating ring width of Mediterranean evergreen species to seasonal and annual variations of precipitation and temperature

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    W. Nijland

    2011-05-01

    Full Text Available Plant growth in Mediterranean landscapes is limited by the typical summer-dry climate. Forests in these areas are only marginally productive and may be quite susceptible to modern climate change. To improve our understanding of forest sensitivity to annual and seasonal climatic variability, we use tree-ring measurements of two Mediterranean evergreen tree species: Quercus ilex L. and Arbutus unedo L. We sampled 34 stems of these species on three different types of substrates in the Peyne study area in southern France. The resulting chronologies were analysed in combination with 38 yr of monthly precipitation and temperature data to reconstruct the response of stem growth to climatic variability. Results indicate a strong positive response to May and June precipitation, as well as a significant positive influence of early-spring temperatures and a negative growth response to summer heat. Comparison of the data with more detailed productivity measurements in two contrasting years confirms these observations and shows a strong productivity limiting effect of low early-summer precipitation. The results show that tree-ring data from Q.ilex and A.unedo can provide valuable information about the response of these tree species to climate variability, improving our ability to predict the effects of climate change in Mediterranean ecosystems.

  13. Composition and diversity of tree species in transects of location lowland evergreen forest of Ecuador

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    Jorge Caranqui A.

    2015-09-01

    Full Text Available The study was conducted in 9 transects 1000m2 of lowland evergreen forest, located in two locations on the coast and one in eastern Ecuador. It was to contribute to knowledge of the diversity and composition of woody plants over 10 cm diameter at breast height (DBH plus infer the state of conservation of forests based on the composition, the number of species, indices diversity and importance value (IV, found in 9 transects of 1000 m² of forest: 156 species, 107 genera and 39 families distributed in 9 transects, in each one the Simpson diversity index is of 0.92 to 0.95, in this case are diversity because all approaches 1. Most were found species aren´t present in all transects, the index value in each transect does not exceed 40%. Grouping transects match three locations exception made to transect 5 and 8 were conducted in disturbed sites, the most transects are intermediate disturbance that their high levels of diversity.

  14. Population genetic structure, genetic diversity, and natural history of the South American species of Nothofagus subgenus Lophozonia (Nothofagaceae) inferred from nuclear microsatellite data.

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    Vergara, Rodrigo; Gitzendanner, Matthew A; Soltis, Douglas E; Soltis, Pamela S

    2014-06-01

    The effect of glaciation on the levels and patterns of genetic variation has been well studied in the Northern Hemisphere. However, although glaciation has undoubtedly shaped the genetic structure of plants in the Southern Hemisphere, fewer studies have characterized the effect, and almost none of them using microsatellites. Particularly, complex patterns of genetic structure might be expected in areas such as the Andes, where both latitudinal and altitudinal glacial advance and retreat have molded modern plant communities. We therefore studied the population genetics of three closely related, hybridizing species of Nothofagus (N. obliqua, N. alpina, and N. glauca, all of subgenus Lophozonia; Nothofagaceae) from Chile. To estimate population genetic parameters and infer the influence of the last ice age on the spatial and genetic distribution of these species, we examined and analyzed genetic variability at seven polymorphic microsatellite DNA loci in 640 individuals from 40 populations covering most of the ranges of these species in Chile. Populations showed no significant inbreeding and exhibited relatively high levels of genetic diversity (H E = 0.502-0.662) and slight, but significant, genetic structure (R ST = 8.7-16.0%). However, in N. obliqua, the small amount of genetic structure was spatially organized into three well-defined latitudinal groups. Our data may also suggest some introgression of N. alpina genes into N. obliqua in the northern populations. These results allowed us to reconstruct the influence of the last ice age on the genetic structure of these species, suggesting several centers of genetic diversity for N. obliqua and N. alpina, in agreement with the multiple refugia hypothesis.

  15. [Biomass allometric equations of nine common tree species in an evergreen broadleaved forest of subtropical China].

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    Zuo, Shu-di; Ren, Yin; Weng, Xian; Ding, Hong-feng; Luo, Yun-jian

    2015-02-01

    Biomass allometric equation (BAE) considered as a simple and reliable method in the estimation of forest biomass and carbon was used widely. In China, numerous studies focused on the BAEs for coniferous forest and pure broadleaved forest, and generalized BAEs were frequently used to estimate the biomass and carbon of mixed broadleaved forest, although they could induce large uncertainty in the estimates. In this study, we developed the species-specific and generalized BAEs using biomass measurement for 9 common broadleaved trees (Castanopsis fargesii, C. lamontii, C. tibetana, Lithocarpus glaber, Sloanea sinensis, Daphniphyllum oldhami, Alniphyllum fortunei, Manglietia yuyuanensis, and Engelhardtia fenzlii) of subtropical evergreen broadleaved forest, and compared differences in species-specific and generalized BAEs. The results showed that D (diameter at breast height) was a better independent variable in estimating the biomass of branch, leaf, root, aboveground section and total tree than a combined variable (D2 H) of D and H (tree height) , but D2H was better than D in estimating stem biomass. R2 (coefficient of determination) values of BAEs for 6 species decreased when adding H as the second independent variable into D- only BAEs, where R2 value for S. sinensis decreased by 5.6%. Compared with generalized D- and D2H-based BAEs, standard errors of estimate (SEE) of BAEs for 8 tree species decreased, and similar decreasing trend was observed for different components, where SEEs of the branch decreased by 13.0% and 20.3%. Therefore, the biomass carbon storage and its dynamic estimates were influenced largely by tree species and model types. In order to improve the accuracy of the estimates of biomass and carbon, we should consider the differences in tree species and model types.

  16. Species differences in evergreen tree transpiration at daily, seasonal, and interannual timescales

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    Link, P.; Simonin, K. A.; Oshun, J.; Dietrich, W.; Dawson, T. E.; Fung, I.

    2012-12-01

    Mediterranean climates have rainy winter and dry summer seasons, so the season of water availability (winter) is out of phase with the season of light availability and atmospheric demand (summer). In this study, we investigate the seasonality of tree transpiration in a Mediterranean climate, using observations from a small (8000 m2), forested, steep (~35 degree) hillslope at the UC Angelo Reserve, in the northern California Coast Range. The site is instrumented with over 850 sensors transmitting hydrologic and meteorological data at less than 30-minute intervals. Here, we analyze four years of high-frequency measurements from 45 sap flow sensors in 30 trees, six depth profiles of soil moisture measured by TDR, and spatially distributed measurements of air temperature, relative humidity, solar radiation, and other meteorological variables. The sap flow measurements show a difference in transpiration seasonality between common California Coast Range evergreen tree species. Douglas firs (Pseudotsuga menziesii) maintain significant transpiration through the winter rainy season and transpire maximally in the spring, but Douglas fir transpiration declines sharply in the summer dry season. Madrones (Arbutus menziesii), in contrast, transpire maximally in the summer dry season. The seasonal patterns are quantified using principal component analysis. Nonlinear regressions against environmental variables show that the difference in transpiration seasonality arises from different sensitivities to atmospheric demand (VPD) and root-zone moisture. The different sensitivities to VPD and root-zone moisture cause species differences not just in seasonal patterns, but also in high temporal frequency (daily to weekly) variability of transpiration. We also contrast the interannual variability of dry season transpiration among the different species, and show that precipitation above a threshold triggers a Douglas fir response. Finally, we use a simple 1-D model of the atmospheric

  17. Pollination ecology of Chengam Scyphiphora hydrophyllacea C.F. Gaertn. (Magnoliopsida: Rubiales: Rubiaceae, a non-viviparous evergreen tree species

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    A.J. Solomon Raju

    2014-12-01

    Full Text Available Scyphiphora hydrophyllacea C.F. Gaertn. or Chengam is a non-viviparous evergreen tree species. The flowers are bisexual, self-compatible, self-pollinating, temporally dioecious and exhibit a mixed breeding system.  The plant is both melittophilous and anemophilous at the study area.  Natural fruit set is 100% but seeds are non-viable which might be due to a genetic disorder. 

  18. Pollination ecology of Chengam Scyphiphora hydrophyllacea C.F. Gaertn. (Magnoliopsida: Rubiales: Rubiaceae), a non-viviparous evergreen tree species

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    A.J. Solomon Raju; B. Rajesh

    2014-01-01

    Scyphiphora hydrophyllacea C.F. Gaertn. or Chengam is a non-viviparous evergreen tree species. The flowers are bisexual, self-compatible, self-pollinating, temporally dioecious and exhibit a mixed breeding system.  The plant is both melittophilous and anemophilous at the study area.  Natural fruit set is 100% but seeds are non-viable which might be due to a genetic disorder. 

  19. Parameterization of the Stomatal Component of the DO3SE Model for Mediterranean Evergreen Broadleaf Species

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    Roccío Alonso

    2007-01-01

    Full Text Available An ozone (O3 deposition model (DO3SE is currently used in Europe to define the areas where O3 concentrations lead to absorbed O3 doses that exceed the flux-based critical levels above which phytotoxic effects would be likely recorded. This mapping exercise relies mostly on the accurate estimation of O3 flux through plant stomata. However, the present parameterization of the modulation of stomatal conductance (gs behavior by different environmental variables needs further adjustment if O3 phytotoxicity is to be assessed accurately at regional or continental scales. A new parameterization of the model is proposed for Holm oak (Quercus ilex, a tree species that has been selected as a surrogate for all Mediterranean evergreen broadleaf species. This parameterization was based on a literature review, and was calibrated and validated using experimentally measured data of gs and several atmospheric and soil parameters recorded at three sites of the Iberian Peninsula experiencing long summer drought, and very cold and dry winter air (El Pardo and Miraflores or milder conditions (Tietar. A fairly good agreement was found between modeled and measured data (R2 = 0.64 at Tietar. However, a reasonable performance (R2 = 0.47–0.62 of the model was only achieved at the most continental sites when gs and soil moisture deficit relationships were considered. The influence of root depth on gs estimation is discussed and recommendations are made to build up separate parameterizations for continental and marine-influenced Holm oak sites in the future.

  20. The rapid climate change-caused dichotomy on subtropical evergreen broad-leaved forest in Yunnan: Reduction in habitat diversity and increase in species diversity

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    Zhe Ren

    2016-06-01

    Full Text Available Yunnan's biodiversity is under considerable pressure and subtropical evergreen broad-leaved forests in this area have become increasingly fragmented through agriculture, logging, planting of economic plants, mining activities and changing environment. The aims of the study are to investigate climate change-induced changes of subtropical evergreen broad-leaved forests in Yunnan and identify areas of current species richness centers for conservation preparation. Stacked species distribution models were created to generate ensemble forecasting of species distributions, alpha diversity and beta diversity for Yunnan's subtropical evergreen broad-leaved forests in both current and future climate scenarios. Under stacked species distribution models in rapid climate changes scenarios, changes of water-energy dynamics may possibly reduce beta diversity and increase alpha diversity. This point provides insight for future conservation of evergreen broad-leaved forest in Yunnan, highlighting the need to fully consider the problem of vegetation homogenization caused by transformation of water-energy dynamics.

  1. Expression of anatomical leaf traits in homoploid hybrids between deciduous and evergreen species of Vaccinium.

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    Piwczyński, M; Ponikierska, A; Puchałka, R; Corral, J M

    2013-05-01

    We investigated the anatomical expression of leaf traits in hybrids between evergreen Vaccinium vitis-idaea and deciduous V. myrtillus. We compared parents from four populations with their respective F1 hybrids and tested whether (i) transgression can be the source of novel anatomical traits in hybrids; (ii) expression of transgressive traits is more probable for traits with similar values in parents and intermediate for more distinct values, as predicted by theory; and (iii) independent origin of hybrids leads to identical trait expression profiles among populations. We found that anatomical leaf traits can be divided into four categories based on their similarity to parents: intermediate, parental-like, transgressive and non-significant. Contrary to the common view, parental-like trait values were equally important in shaping the hybrid profile, as were intermediate traits. Transgression was revealed in 17/144 cases and concerned mainly cell and tissue sizes. As predicted by theory, we observed transgressive segregation more often when there was little phenotypic divergence, but intermediate values when parental traits were differentiated. It is likely that cell and tissue sizes are phylogenetically more conserved due to stabilising selection, whereas traits such as leaf thickness and volume fraction of the intercellular spaces, showing a consistent intermediate pattern across populations, are more susceptible to directional selection. Hybrid populations showed little similarity in expression profile, with only three traits identically expressed across all populations. Thus local adaptation of parental species and specific genetic background may be of importance. © 2012 German Botanical Society and The Royal Botanical Society of the Netherlands.

  2. Xanthophyll cycle pigment and antioxidant profiles of winter-red (anthocyanic) and winter-green (acyanic) angiosperm evergreen species.

    Science.gov (United States)

    Hughes, Nicole M; Burkey, Kent O; Cavender-Bares, Jeannine; Smith, William K

    2012-03-01

    Leaves of many angiosperm evergreen species change colour from green to red during winter, corresponding with the synthesis of anthocyanin pigments. The ecophysiological function of winter colour change (if any), and why it occurs in some species and not others, are not yet understood. It was hypothesized that anthocyanins play a compensatory photoprotective role in species with limited capacity for energy dissipation. Seasonal xanthophyll pigment content, chlorophyll fluorescence, leaf nitrogen, and low molecular weight antioxidants (LMWA) of five winter-red and five winter-green angiosperm evergreen species were compared. Our results showed no difference in seasonal xanthophyll pigment content (V+A+Z g(-1) leaf dry mass) or LMWA between winter-red and winter-green species, indicating red-leafed species are not deficient in their capacity for non-photochemical energy dissipation via these mechanisms. Winter-red and winter-green species also did not differ in percentage leaf nitrogen, corroborating previous studies showing no difference in seasonal photosynthesis under saturating irradiance. Consistent with a photoprotective function of anthocyanin, winter-red species had significantly lower xanthophyll content per unit chlorophyll and less sustained photoinhibition than winter-green species (i.e. higher pre-dawn F(v)/F(m) and a lower proportion of de-epoxidized xanthophylls retained overnight). Red-leafed species also maintained a higher maximum quantum yield efficiency of PSII at midday (F'(v)/F'(m)) during winter, and showed characteristics of shade acclimation (positive correlation between anthocyanin and chlorophyll content, and negative correlation with chlorophyll a/b). These results suggest that the capacity for photon energy dissipation (photochemical and non-photochemical) is not limited in red-leafed species, and that anthocyanins more likely function as an alternative photoprotective strategy to increased VAZ/Chl during winter.

  3. Cophylogeny and biogeography of the fungal parasite Cyttaria and its host Nothofagus, southern beech

    National Research Council Canada - National Science Library

    Kristin R. Peterson; Donald H. Pfister; Charles D. Bell

    2010-01-01

    The obligate, biotrophic association among species of the fungal genus Cyttaria and their hosts in the plant genus Nothofagus often is cited as a classic example of cophylogeny and is one of the few...

  4. Pollen morphology of Nothofagus (Nothofagaceae, Fagales and its phylogenetic significance

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    Fernández Damián Andrés

    2016-12-01

    Full Text Available Nothofagaceae (southern beeches are a relatively small flowering plant family of trees confined to the Southern Hemisphere. The fossil record of the family is abundant and it has been widely used as a test case for the classic hypothesis that Antarctica, Patagonia, Australia and New Zealand were once joined together. Although the phylogenetic relationships in Nothofagus appear to be well supported, the evolution of some pollen morphological traits remains elusive, largely because of the lack of ultrastructural analyses. Here we describe the pollen morphology of all extant South American species of Nothofagus, using scanning electron microscopy (SEM, transmission electron microscopy (TEM and light microscopy (LM, and reconstruct ancestral character states using a well-supported phylogenetic tree of the family. Our results indicate that the main differences between pollen of subgenera Fuscospora (pollen type fusca a and Nothofagus (pollen type fusca b are related to the size of microspines (distinguishable or not in optical section, and the thickening of colpi margins (thickened inwards, or thickened both inwards and outwards. In particular, Nothofagus alessandrii, the only extant South American species of subgenus Fuscospora, presents distinctive pollen features that have not been observed in any other species of the genus (i.e. a large granular infratectum and spongy apertural endexine. Species of subgenus Lophozonia are characterized by having the largest pollen grains, with polygonal outline in polar view, microspines distinguishable in optical section, long and non-thickened colpi, and a thin endexine. The reconstruction of character states for the node corresponding to the common ancestor to genus Nothofagus leads us to conclude that the ancestral form of Nothofagaceae should have had: equatorial diameter < 40 μm, circular outline in polar view, microspines distinguishable in optical section, short colpi thickened inwards, and a thin

  5. Partitioning Tree Species Diversity and Developmental Changes in Habitat Associations in a Subtropical Evergreen Broadleaf Secondary Forest in Southern China

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    Wei Cui

    2016-10-01

    Full Text Available The classical environmental control model assumes that species diversity is primarily determined by environmental conditions (e.g., microclimate and soil on the local scale. This assumption has been challenged by the neutral theory that assumes that the maintenance of biodiversity mainly depends on the ecological drift and dispersal limitation. Understanding the mechanisms that maintain biodiversity depends on decomposing the variation of species diversity into the contributions from the various components that affect it. We investigated and partitioned the effects of the biotic component (productivity, forest spatial structure and the environmental component (topography and soil fertility on the distribution of tree species richness jointly (the combined effect of environment and biotic process and separately (the effect of environment or biotic process alone in 25 permanent plots of 600 m2 in a subtropical evergreen broadleaf secondary forest in southern China. The analysis was also completed for trees at different growth stages based on diameter breast height (young trees: 5 cm ≤ DBH < 10 cm, mature trees: 10 cm < DBH ≤ 20 cm, old trees: DBH > 20 cm within each plot. Our results indicated that (1 tree species richness had significant negative relationship with productivity and a unimodal relationship with its spatially structured distribution; (2 biotic and environmental factors both have significant influence on species richness and jointly explain ~60% of the variation for the overall tree assemblage, and the variation explained by the two components jointly increased across growth stages (34%, 44%, and 75%, respectively; (3 additive variation partitioning revealed that the tree species richness was dominantly controlled by environmental factors (32%, while the biotic component also independently contributed a non-negligible effect (16%; and (4 the dominant fraction changed from the biotic component to the environmental component across

  6. Influences of evergreen gymnosperm and deciduous angiosperm tree species on the functioning of temperate and boreal forests

    DEFF Research Database (Denmark)

    Augusto, Laurent; De Schrijver, An; Vesterdal, Lars

    2015-01-01

    It has been recognized for a long time that the overstorey composition of a forest partly determines its biological and physical-chemical functioning. Here, we review evidence of the influence of evergreen gymnosperm (EG) tree species and deciduous angiosperm (DA) tree species on the water balance...... of their tissues, higher soil moisture and favourable conditions for earthworms. Forest floors consequently tend to be thicker in EG forests compared to DA forests. Many factors, such as litter lignin content, influence litter decomposition and it is difficult to identify specific litter-quality parameters...... that distinguish litter decomposition rates of EGs from DAs. Although it has been suggested that DAs can result in higher accumulation of soil carbon stocks, evidence from field studies does not show any obvious trend. Further research is required to clarify if accumulation of carbon in soils (i.e. forest floor...

  7. Geographical and climatic gradients of evergreen versus deciduous broad-leaved tree species in subtropical China: Implications for the definition of the mixed forest.

    Science.gov (United States)

    Ge, Jielin; Xie, Zongqiang

    2017-06-01

    Understanding climatic influences on the proportion of evergreen versus deciduous broad-leaved tree species in forests is of crucial importance when predicting the impact of climate change on broad-leaved forests. Here, we quantified the geographical distribution of evergreen versus deciduous broad-leaved tree species in subtropical China. The Relative Importance Value index (RIV) was used to examine regional patterns in tree species dominance and was related to three key climatic variables: mean annual temperature (MAT), minimum temperature of the coldest month (MinT), and mean annual precipitation (MAP). We found the RIV of evergreen species to decrease with latitude at a lapse rate of 10% per degree between 23.5 and 25°N, 1% per degree at 25-29.1°N, and 15% per degree at 29.1-34°N. The RIV of evergreen species increased with: MinT at a lapse rate of 10% per °C between -4.5 and 2.5°C and 2% per °C at 2.5-10.5°C; MAP at a lapse rate of 10% per 100 mm between 900 and 1,600 mm and 4% per 100 mm between 1,600 and 2,250 mm. All selected climatic variables cumulatively explained 71% of the geographical variation in dominance of evergreen and deciduous broad-leaved tree species and the climatic variables, ranked in order of decreasing effects were as follows: MinT > MAP > MAT. We further proposed that the latitudinal limit of evergreen and deciduous broad-leaved mixed forests was 29.1-32°N, corresponding with MAT of 11-18.1°C, MinT of -2.5 to 2.51°C, and MAP of 1,000-1,630 mm. This study is the first quantitative assessment of climatic correlates with the evergreenness and deciduousness of broad-leaved forests in subtropical China and underscores that extreme cold temperature is the most important climatic determinant of evergreen and deciduous broad-leaved tree species' distributions, a finding that confirms earlier qualitative studies. Our findings also offer new insight into the definition and distribution of the mixed forest and an accurate

  8. Litterfall, litter decomposition and nitrogen mineralization in old-growth evergreen and secondary deciduous Nothofagus forests in south-central Chile Aporte, descomposición de hojarasca y mineralización de nitrógeno en bosques siempreverdes de antiguo crecimiento y bosques secundarios deciduos, centro-sur de Chile

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    JEROEN STAELENS

    2011-03-01

    Full Text Available South Chilean forest ecosystems represent one of the largest areas of old-growth temperate rainforests remaining in the Southern hemisphere and have a high ecological value, but suffer from deforestation, invasion by exotic species, fragmentation, and increasing atmospheric nitrogen (N deposition. To support sustainable forest management, more knowledge is required on nutrient cycling of these ecosystems. Therefore, a descriptive study of nutrient dynamics was done in four Valdivian rainforests in the lower Andes range of south Chile: old-growth and altered evergreen stands and unmanaged and managed secondary deciduous stands. Time series were measured for (i mass (four year and nutrient content (N, K, Ca, and Mg; one year of litterfall, (ii decomposition and nutrient dynamics (N, C, K, Ca, Mg, and P; one year of leaf litter and Saxegothaea conspicua bark litter, and (iii in situ topsoil net N mineralization (one year. Litterfall in the four stands ranged from 3.5 to 5.8 ton ha-1 yr-1, was temporarily lower in the managed than in the unmanaged deciduous stand and had a different seasonality in the evergreen stands than in the deciduous stands. Leaf litter decomposed faster (on average 32 % mass loss after one year than bark litter (8 % but without significant differences between leaf litter types. Net N in evergreen leaf litter decreased during decomposition but increased in deciduous leaf litter. Net soil N mineralization was fastest in the pristine evergreen stand, intermediate in the deciduous stands and slowest in the altered evergreen forest. Given the absence of replicated stands, the definite impact of forest type or management regime on the internal nutrient cycling cannot be demonstrated. Nevertheless, the results suggest that management can affect nutrient turnover by altering species composition and forest structure, while recent (five years selective logging in secondary deciduous forest did not affect litter decomposition or N

  9. Elevation and vegetation influences on soil properties in Chilean Nothofagus forests Influencia de la elevación y la vegetación sobre las propiedades del suelo de los bosques chilenos de Nothofagus

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    KELLY L.M DECKER

    2003-09-01

    Full Text Available We measured net nitrogen mineralization, net nitrification, proportional nitrification, and total inorganic nitrogen, available phosphorus, and soil organic carbon in five Andean forested stands in an attempt to resolve the relative influence of elevation and forest canopy composition on soil organic matter and nutrient dynamics in this ecosystem type. Our five forested study sites were within a contiguous Nothofagus forest that ranged from 1,280 to 1,700 m elevation in the central Chilean Andes. The five sites consisted of three single species stands, one each of the low elevation deciduous N. obliqua, the evergreen N. dombeyi, or the high elevation deciduous N. pumilio, as well as two mixed evergreen-deciduous stands. There was no statistically significant relationship of nitrogen mineralization or phosphorus with elevation. In contrast, there were statistically significant, though weak, negative relationships between elevation and net nitrification, proportional nitrification, soil pH and organic carbon. In general, soils from the N. obliqua stand had higher levels/rates of nitrification, soil organic carbon content, soil pH, and plant available phosphorus than soils form the other single species stands. In contrast, the N. dombeyi and N. pumilio stands had lower rates of nitrification and soil pH than did the N. obliqua stand. The evergreen-deciduous mixed stands tended to be intermediate in soil properties. These results demonstrate that vegetation, particularly the balance of evergreen and deciduous species, exerts stronger control over soil chemical and biochemical properties than the climate variations induced by 350 m in elevation, even where the evergreen and deciduous species are closely-related angiosperms.Medimos la mineralización neta de nitrógeno, la nitrificación, el total de nitrógeno disponible, el fósforo disponible y el carbono orgánico del suelo en cinco rodales forestales andinos con el propósito de separar la

  10. Differences in construction costs and chemical composition between deciduous and evergreen woody species are small as compared to differences among families.

    Science.gov (United States)

    Villar, Rafael; Robleto, Jeannette Ruiz; De Jong, Yvonne; Poorter, Hendrik

    2006-08-01

    We tested to what extent differences in construction costs (CC) and chemical composition of woody species are attributed to leaf habit. Eight evergreen and eight deciduous species belonging to six families were selected to form eight phylogenetic independent contrasts (PICs). The plants were grown from seed in a glasshouse. Differences in leaf, stem and root CC between evergreen and deciduous species were minor, the proportion of variance explained by leaf habit generally being less than 6%. Surprisingly, differences in leaf chemical composition between deciduous and evergreen species were small as well. Variation in CC and chemical composition among families was substantial, the factor 'family' explaining 50-85% of variance. We therefore conclude that in this case, phylogeny is a more important factor than functional group. Leaves of the fast-growing species in this experiment showed high levels of minerals, organic acids, proteins and lipids, whereas leaves of the slow-growing species had higher concentrations of soluble phenolics, lignin as well as higher carbon/nitrogen (C/N) ratio. These relationships suggest a trade-off between growth and defence. In contrast, CC of leaves, stems, roots or whole plants showed no or only a weak correlation with relative growth rate (RGR). The C/N ratio of the leaves is an easily measured parameter that correlated strongly in a negative way with the RGR of the plants and reflected better the balance between investment in structure and physiological functioning than CC.

  11. Relaxed molecular clock provides evidence for long-distance dispersal of Nothofagus (southern beech.

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    Michael Knapp

    2005-01-01

    Full Text Available Nothofagus (southern beech, with an 80-million-year-old fossil record, has become iconic as a plant genus whose ancient Gondwanan relationships reach back into the Cretaceous era. Closely associated with Wegener's theory of "Kontinentaldrift", Nothofagus has been regarded as the "key genus in plant biogeography". This paradigm has the New Zealand species as passengers on a Moa's Ark that rafted away from other landmasses following the breakup of Gondwana. An alternative explanation for the current transoceanic distribution of species seems almost inconceivable given that Nothofagus seeds are generally thought to be poorly suited for dispersal across large distances or oceans. Here we test the Moa's Ark hypothesis using relaxed molecular clock methods in the analysis of a 7.2-kb fragment of the chloroplast genome. Our analyses provide the first unequivocal molecular clock evidence that, whilst some Nothofagus transoceanic distributions are consistent with vicariance, trans-Tasman Sea distributions can only be explained by long-distance dispersal. Thus, our analyses support the interpretation of an absence of Lophozonia and Fuscospora pollen types in the New Zealand Cretaceous fossil record as evidence for Tertiary dispersals of Nothofagus to New Zealand. Our findings contradict those from recent cladistic analyses of biogeographic data that have concluded transoceanic Nothofagus distributions can only be explained by vicariance events and subsequent extinction. They indicate that the biogeographic history of Nothofagus is more complex than envisaged under opposing polarised views expressed in the ongoing controversy over the relevance of dispersal and vicariance for explaining plant biodiversity. They provide motivation and justification for developing more complex hypotheses that seek to explain the origins of Southern Hemisphere biota.

  12. Particulate matter deposited on leaf of five evergreen species in Beijing, China: Source identification and size distribution

    Science.gov (United States)

    Song, Yingshi; Maher, Barbara A.; Li, Feng; Wang, Xiaoke; Sun, Xiao; Zhang, Hongxing

    2015-03-01

    Airborne particulate matter (PM) has become a serious problem, and urban plants can play important roles in reducing PM concentrations in the air. The morphology, size, and elemental composition of PM on tree leaves (five evergreen species) from Beijing, China, were obtained, together with number density of PM size fraction, by using scanning electron microscopy (SEM) and energy dispersive X-rays (EDX). The rinse and weigh method was used to characterize PM in three size categories (0.2-2.5 μm, 2.5-10 μm, and 10-100 μm). The results showed that PM up to 2 μm can get into the stomatal cavity, and the most furrowed areas of the leaf surfaces were sites of maximum PM deposition. The leaf-deposited PM mainly comprised C, O, Si, and Fe. The number of particles per leaf per cm2 was 1.95 × 107, and 96% of the particles were less than 2.5 μm. The mass concentration was 148.44 μg/cm2, and PM2.5 comprised only 2.09% by weight while PM larger than 10 μm comprised 79%. Juniperus formosana was most effective at mitigating airborne PM on the leaf scale. Pinus bungeana accumulated the most PM on the tree scale. The results showed that urban plants can play important roles in mitigating urban airborne PM.

  13. Cophylogeny and biogeography of the fungal parasite Cyttaria and its host Nothofagus, southern beech.

    Science.gov (United States)

    Peterson, Kristin R; Pfister, Donald H; Bell, Charles D

    2010-01-01

    The obligate, biotrophic association among species of the fungal genus Cyttaria and their hosts in the plant genus Nothofagus often is cited as a classic example of cophylogeny and is one of the few cases in which the biogeography of a fungus is commonly mentioned or included in biogeographic analyses. In this study molecular and morphological data are used to examine hypotheses regarding the cophylogeny and biogeography of the 12 species of Cyttaria and their hosts, the 11 species of Nothofagus subgenera Lophozonia and Nothofagus. Our results indicate highly significant overall cophylogenetic structure, despite the fact that the associations between species of Cyttaria and Nothofagus usually do not correspond in a simple one to one relationship. Two major lineages of Cyttaria are confined to a single Nothofagus subgenus, a specificity that might account for a minimum of two codivergences. We hypothesize other major codivergences. Numerous extinction also are assumed, as are an independent parasite divergence followed by host switching to account for C. berteroi. Considering the historical association of Cyttaria and Nothofagus, our hypothesis may support the vicariance hypothesis for the trans-Antarctic distribution between Australasian and South American species of Cyttaria species hosted by subgenus Lophozonia. It also supports the hypothesis of transoceanic long distance dispersal to account for the relatively recent relationship between Australian and New Zealand Cyttaria species, which we estimate to have occurred 44.6-28.5 mya. Thus the history of these organisms is not only a reflection of the breakup of Gondwana but also of other events that have contributed to the distributions of many other southern hemisphere plants and fungi.

  14. Effect of Severe Winter Cold on the Photosynthetic Potentials of Three Co-occurring Evergreen Woody Species in a Mediterranean Forest, Catalonia (Spain)

    Science.gov (United States)

    Sperlich, Dominik; Gracia, Carlos; Peñuelas, Josep; Sabaté, Santi

    2013-04-01

    Evergreen tree species in the Mediterranean region have to cope with a wide range of environmental stress conditions from summer drought to winter cold. The winter period can lead to photoinhibition due to a combination of high solar irradiances and chilling temperatures which can reduce the light saturation point. However, Mediterranean winter mildness can lead periodically to favourable environmental conditions above the threshold for positive carbon balance benefitting evergreen woody species in contrast to winter deciduous species. The advantage of being able to photosynthesis all year round with a significant fraction in the winter month is compensating for the lower photosynthetic potentials during spring and summer in comparison to deciduous species. In this work, we investigated the physiological behaviour of three evergreen tree species (Quercus ilex, Pinus halepensis, Arbutus undeo) co-occurring in a natural and mature Mediterranean forest after a period of mild winter conditions and their response to a sudden period of intense cold weather. Therefore, we examined in each period the photosynthetic potentials by estimating the maximum carboxylation rate (Vcmax) and the maximum electron transport rate (Jmax) through gas exchange measurements. The results indicate that all species exhibited extraordinary high photosynthetic potentials during the first period of measurement as a response to the mild conditions. However, the sudden cold period affected negatively the photosynthetic potentials of Quercus ilex and A. unedo with reduction ranging between 37 to 45 %, whereas they were observed to be only insignificantly reduced in Pinus halepensis. Our results can be explained by previous classifications into photoinhibition-avoiding (P. halpensis) and photoinhibition-tolerant (Q. ilex, A. undeo) species on the basis of their susceptibility to dynamic photoinhibition (Martinez Ferri 2000). Photoinhibition tolerant species are characterised with a more dynamic

  15. Genetic differentiation and genetic diversity of Castanopsis (Fagaceae, the dominant tree species in Japanese broadleaved evergreen forests, revealed by analysis of EST-associated microsatellites.

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    Kyoko Aoki

    Full Text Available The broadleaved evergreen forests of the East Asian warm temperate zone are characterised by their high biodiversity and endemism, and there is therefore a need to extend our understanding of its genetic diversity and phylogeographic patterns. Castanopsis (Fagaceae is one of the dominant tree species in the broadleaved evergreen forests of Japan. In this study we investigate the genetic diversity, genetic structure and leaf epidermal morphology of 63 natural populations of C. sieboldii and C. cuspidata, using 32 Expressed Sequence Tag associated microsatellites. The overall genetic differentiation between populations was low (GST = 0.069 in C. sieboldii and GST = 0.057 in C. cuspidata. Neighbor-joining tree and Bayesian clustering analyses revealed that the populations of C. sieboldii and C. cuspidata were genetically clearly differentiated, a result which is consistent with the morphology of their epidermal cell layers. This suggests that C. sieboldii and C. cuspidata should be treated as independent species, although intermediate morphologies are often observed, especially at sites where the two species coexist. The higher level of genetic diversity observed in the Kyushu region (for both species and the Ryukyu Islands (for C. sieboldii is consistent with the available fossil pollen data for Castanopsis-type broadleaved evergreen trees during the Last Glacial Maximum and suggests the existence of refugia for Castanopsis forests in southern Japan. Within the C. sieboldii populations, Bayesian clustering analyses detected three clusters, in the western and eastern parts of the main islands and in the Ryukyu Islands. The west-east genetic differentiation observed for this species in the main islands, a pattern which is also found in several plant and animal species inhabiting Castanopsis forests in Japan, suggests that they have been isolated from each other in the western and eastern populations for an extended period of time, and may

  16. Influences of evergreen gymnosperm and deciduous angiosperm tree species on the functioning of temperate and boreal forests.

    Science.gov (United States)

    Augusto, Laurent; De Schrijver, An; Vesterdal, Lars; Smolander, Aino; Prescott, Cindy; Ranger, Jacques

    2015-05-01

    It has been recognized for a long time that the overstorey composition of a forest partly determines its biological and physical-chemical functioning. Here, we review evidence of the influence of evergreen gymnosperm (EG) tree species and deciduous angiosperm (DA) tree species on the water balance, physical-chemical soil properties and biogeochemical cycling of carbon and nutrients. We used scientific publications based on experimental designs where all species grew on the same parent material and initial soil, and were similar in stage of stand development, former land use and current management. We present the current state of the art, define knowledge gaps, and briefly discuss how selection of tree species can be used to mitigate pollution or enhance accumulation of stable organic carbon in the soil. The presence of EGs generally induces a lower rate of precipitation input into the soil than DAs, resulting in drier soil conditions and lower water discharge. Soil temperature is generally not different, or slightly lower, under an EG canopy compared to a DA canopy. Chemical properties, such as soil pH, can also be significantly modified by taxonomic groups of tree species. Biomass production is usually similar or lower in DA stands than in stands of EGs. Aboveground production of dead organic matter appears to be of the same order of magnitude between tree species groups growing on the same site. Some DAs induce more rapid decomposition of litter than EGs because of the chemical properties of their tissues, higher soil moisture and favourable conditions for earthworms. Forest floors consequently tend to be thicker in EG forests compared to DA forests. Many factors, such as litter lignin content, influence litter decomposition and it is difficult to identify specific litter-quality parameters that distinguish litter decomposition rates of EGs from DAs. Although it has been suggested that DAs can result in higher accumulation of soil carbon stocks, evidence from

  17. Nothofagus, key genus of plant geography, in time and space, living and fossil, ecology and phylogeny

    NARCIS (Netherlands)

    Steenis, van C.G.G.J.

    1971-01-01

    Data are given on the taxonomy and ecology of the genus. Some New Caledonian species grow in or descend to the lowland. Details are provided on the distribution within New Guinea. For dominance of Nothofagus, and Fagaceae in general, it is suggested that possibly symbionts may contribute to this.

  18. Phylogeography of Phytophagous Weevils and Plant Species in Broadleaved Evergreen Forests: A Congruent Genetic Gap between Western and Eastern Parts of Japan

    Directory of Open Access Journals (Sweden)

    Kyoko Aoki

    2011-04-01

    Full Text Available The Quaternary climate cycles played an important role in shaping the distribution of biodiversity among current populations, even in warm-temperate zones, where land was not covered by ice sheets. We focused on the Castanopsis-type broadleaved evergreen forest community in Japan, which characterizes the biodiversity and endemism of the warm-temperate zone. A comparison of the phylogeographic patterns of three types of phytophagous weevils associated with Castanopsis (a host-specific seed predator, a generalist seed predator, and a host-specific leaf miner and several other plant species inhabiting the forests revealed largely congruent patterns of genetic differentiation between western and eastern parts of the main islands of Japan. A genetic gap was detected in the Kii Peninsula to Chugoku-Shikoku region, around the Seto Inland Sea. The patterns of western-eastern differentiation suggest past fragmentation of broadleaved evergreen forests into at least two separate refugia consisting of the southern parts of Kyushu to Shikoku and of Kii to Boso Peninsula. Moreover, the congruent phylogeographic patterns observed in Castanopsis and the phytophagous insect species imply that the plant-herbivore relationship has been largely maintained since the last glacial periods. These results reinforce the robustness of the deduced glacial and postglacial histories of Castanopsis-associated organisms.

  19. Phylogeography of Phytophagous Weevils and Plant Species in Broadleaved Evergreen Forests: A Congruent Genetic Gap between Western and Eastern Parts of Japan.

    Science.gov (United States)

    Aoki, Kyoko; Kato, Makoto; Murakami, Noriaki

    2011-04-21

    The Quaternary climate cycles played an important role in shaping the distribution of biodiversity among current populations, even in warm-temperate zones, where land was not covered by ice sheets. We focused on the Castanopsis-type broadleaved evergreen forest community in Japan, which characterizes the biodiversity and endemism of the warm-temperate zone. A comparison of the phylogeographic patterns of three types of phytophagous weevils associated with Castanopsis (a host-specific seed predator, a generalist seed predator, and a host-specific leaf miner) and several other plant species inhabiting the forests revealed largely congruent patterns of genetic differentiation between western and eastern parts of the main islands of Japan. A genetic gap was detected in the Kii Peninsula to Chugoku-Shikoku region, around the Seto Inland Sea. The patterns of western-eastern differentiation suggest past fragmentation of broadleaved evergreen forests into at least two separate refugia consisting of the southern parts of Kyushu to Shikoku and of Kii to Boso Peninsula. Moreover, the congruent phylogeographic patterns observed in Castanopsis and the phytophagous insect species imply that the plant-herbivore relationship has been largely maintained since the last glacial periods. These results reinforce the robustness of the deduced glacial and postglacial histories of Castanopsis-associated organisms.

  20. Species-specific and seasonal differences in chlorophyll fluorescence and photosynthetic light response among three evergreen species in a Madrean sky island mixed conifer forest

    Science.gov (United States)

    Potts, D. L.; Minor, R. L.; Braun, Z.; Barron-Gafford, G. A.

    2012-12-01

    -use efficiency (AQE) was similar among P. strobiformis and P. ponderosa and least in P. menziesii (repeated-measures ANOVA; species, F2,8 = 13.83, P = 0.002). Across all three species, monsoon onset increased AQE (repeated-measures ANOVA; time, F1,8= 10.04, P = 0.01). Likewise, P. strobiformis and P. ponderosa shared a similar, greater light compensation point than P. menziesii (repeated-measures ANOVA; species, F2,8 = 5.89, P = 0.02). However, across species, monsoon onset did not influence light compensation points. These results support the hypothesis that the monsoon has species-specific effects on evergreen physiological performance and are broadly consistent with predictions of stress tolerance based on species' latitudinal and elevational range distributions. Moreover, with year-to-year rainfall variability predicted to increase under future climate scenarios, species-specific functional traits related to stress tolerance and photosynthesis may promote ecosystem functional resilience in Madrean sky island mixed conifer forests.

  1. [Species-area relationship at different succession stages of monsoon evergreen broad-leaved forest in south subtropical area of Yunnan Province].

    Science.gov (United States)

    Liu, Wan-De; Su, Jian-Rong; Li, Shuai-Feng; Zhang, Zhi-Jun; Lang, Xue-Dong

    2011-02-01

    Based on the investigation data of monsoon evergreen broad-leaved forest at its different succession stages (primary, CP; 15 years of succession, CF; and 30 years of succession, CT) in Pu' er of Yunnan Province, this paper studied the species-area relationship of this forest at each succession stage. It was found that in the communities at each succession stage, the number of total species, trees, shrubs, and lianas had a significant correlation with sampling area, with the area explained over 94% of the total variation. The Z value of the total species (0.334) and trees (0.394) was the lowest at CT, whereas that of shrubs (0.437) and lianas (0.326) was the lowest at CF. No significant differences were observed in the intercepts of the species-area curve of total species, trees, shrubs, and lianas among different succession stages, but the coefficient of determination (R2) of the species-area curve of total species and lianas was the highest at CP. The richness of trees and shrubs at CF explained 99.9% of the variance of Z value, but the richness of total species, trees, shrubs, and lianas at CP and CT had no significant correlations with the Z value.

  2. Radiocarbon as a biomarker of urban pollution in leaves of evergreen species sampled in Rome and in rural areas (Lazio—Central Italy)

    Science.gov (United States)

    Alessio, M.; Anselmi, S.; Conforto, L.; Improta, S.; Manes, F.; Manfra, L.

    The aim of the present study is the use of 14C, sampled in leaves of evergreen species, as a natural geochemical marker to estimate the contribution of artificial sources (heating plants, vehicles, etc.) to the complex of atmospheric gases in an urban environment. Leaves were chosen due to sampling easiness and their reliability: in particular the evergreen species, being exposed all the year round to pollutants are especially indicated for bioindication and biomonitoring studies. The response to atmospheric pollutants has been studied of two plant species ( Quercus ilex L., Pinus pinea L.) measuring isotopic ( 14r, δ13C), chemical (Pb concentration) and ecophysiological (gaseous exchange and leaf fluorescence of chlorophyll a) parameters. Leaves of holm-oaks and stone pine needles collected over a 3-year time span in an urban park in Rome (Villa Ada) and in reference localities outside the city on the Tyrrhenian coast and in the pre-Appennine area have been analysed. In Villa Ada measurements were carried out along a transect from the road bordering the park towards the interior; all the parameters, together in agreement, showed a decreasing pollution gradient towards the inner park. It was possible to estimate a 5.5±0.3% contribution of CO 2 from fossil fuels close to the road, decreasing to 1.7±0.3% at pollution from fossil fuels, while δ13C appears to be conditioned mainly by the interspecific difference, and also by many other environmental factors that affect the plant functionality. Results confirmed that radiocarbon is a useful tool in environmental studies, allowing to quantify the contributions of CO 2 of anthropic origin: this parameter, together with appropriate isotopic, chemical and ecophysiological analyses, could provide a good indication of the "air quality" in urban and rural contexts.

  3. Radiocarbon as a bio marker of urban pollution in leaves of evergreen species sampled in Rome and in rural areas (Lazio-Central Italy)

    Energy Technology Data Exchange (ETDEWEB)

    Alessio, M.; Improta, S. [La Sapienza University, Rome (Italy). Department of Physics; Anselmi, S. [University of Molise, Isernia (Italy). Department of Sciences and Technologies for the Environment; Conforto, L.; Manfra, L. [La Sapienza University, Rome (Italy). Department of Earth Sciences; Manes, F. [La Sapienza University, Rome (Italy). Department of Plant Biology

    2002-11-01

    The aim of the present study is the use of {sup 14}C, sampled in leaves of evergreen species, as a natural geochemical marker to estimate the contribution of artificial sources (heating plants, vehicles, etc.) to the complex of atmospheric gases in an urban environment. Leaves were chosen due to sampling easiness and their reliability: in particular the evergreen species, being exposed all the year round to pollutants are especially indicated for bioindication and biomonitoring studies. The response to atmospheric pollutants has been studied of two plant species (Quercus ilex L., Pinus pinea L.) measuring isotopic ({sup 14}r, {delta}{sup 13}C), chemical (Pb concentration) and ecophysiological (gaseous exchange and leaf fluorescence of chlorophyll a) parameters. Leaves of holm-oaks and stone pine needles collected over a 3-year time span in an urban park in Rome (Villa Ada) and in reference localities outside the city on the Tyrrhenian coast and in the pre-Appennine area have been analysed. In Villa Ada measurements were carried out along a transect from the road bordering the park towards the interior; all the parameters, together in agreement, showed a decreasing pollution gradient towards the inner park. It was possible to estimate a 5.5{+-}0.3% contribution of CO{sub 2} from fossil fuels close to the road, decreasing to 1.7{+-}0.3% at <300 m from it towards the inner park. The isotopic analyses conducted on stone pines and holm-oaks show that {sup 14}C provides indications on the degree of pollution from fossil fuels, while {delta}{sup 13}C appears to be conditioned mainly by the interspecific difference, and also by many other environmental factors that affect the plant functionality. Results confirmed that radiocarbon is a useful tool in environmental studies, allowing to quantify the contributions of CO{sub 2} of anthropic origin: this parameter, together with appropriate isotopic, chemical and ecophysiological analyses, could provide a good indication of the

  4. Characterisation of ectomycorrhizal formation by the exotic fungus Amanita muscaria with Nothofagus cunninghamii in Victoria, Australia.

    Science.gov (United States)

    Dunk, Christopher William; Lebel, Teresa; Keane, Philip J

    2012-02-01

    The occurrence of the exotic ectomycorrhizal fungus Amanita muscaria in a mixed Nothofagus-Eucalyptus native forest was investigated to determine if A. muscaria has switched hosts to form a successful association with a native tree species in a natural environment. A mycorrhizal morphotype consistently found beneath A. muscaria sporocarps was examined, and a range of morphological and anatomical characteristics in common with those described for ectomycorrhizae formed by A. muscaria on a broad range of hosts were observed. A full description is provided. The likely plant associate was determined to be Nothofagus cunninghamii based upon anatomy of the roots. Analysis of ITS-1 and ITS-2 regions of nuclear ribosomal DNA sequences confirmed the identities of both fungal and plant associates. These findings represent conclusive evidence of the invasion of a non-indigenous ectomycorrhizal fungus into native forest and highlight the ecological implications of this discovery.

  5. Phylogenetic Structure of Tree Species across Different Life Stages from Seedlings to Canopy Trees in a Subtropical Evergreen Broad-Leaved Forest.

    Science.gov (United States)

    Jin, Yi; Qian, Hong; Yu, Mingjian

    2015-01-01

    Investigating patterns of phylogenetic structure across different life stages of tree species in forests is crucial to understanding forest community assembly, and investigating forest gap influence on the phylogenetic structure of forest regeneration is necessary for understanding forest community assembly. Here, we examine the phylogenetic structure of tree species across life stages from seedlings to canopy trees, as well as forest gap influence on the phylogenetic structure of forest regeneration in a forest of the subtropical region in China. We investigate changes in phylogenetic relatedness (measured as NRI) of tree species from seedlings, saplings, treelets to canopy trees; we compare the phylogenetic turnover (measured as βNRI) between canopy trees and seedlings in forest understory with that between canopy trees and seedlings in forest gaps. We found that phylogenetic relatedness generally increases from seedlings through saplings and treelets up to canopy trees, and that phylogenetic relatedness does not differ between seedlings in forest understory and those in forest gaps, but phylogenetic turnover between canopy trees and seedlings in forest understory is lower than that between canopy trees and seedlings in forest gaps. We conclude that tree species tend to be more closely related from seedling to canopy layers, and that forest gaps alter the seedling phylogenetic turnover of the studied forest. It is likely that the increasing trend of phylogenetic clustering as tree stem size increases observed in this subtropical forest is primarily driven by abiotic filtering processes, which select a set of closely related evergreen broad-leaved tree species whose regeneration has adapted to the closed canopy environments of the subtropical forest developed under the regional monsoon climate.

  6. Effect of Disturbance Regimes on Spatial Patterns of Tree Species in Three Sites in a Tropical Evergreen Forest in Vietnam

    Directory of Open Access Journals (Sweden)

    Do Thi Ngoc Le

    2016-01-01

    Full Text Available The effects of disturbance regimes on the spatial patterns of the five most abundant species were investigated in three sites in a tropical forest at Xuan Nha Nature Reserve, Vietnam. Three permanent one-ha plots were established in undisturbed forest (UDF, lightly disturbed forest (LDF, and highly disturbed forest (HDF. All trees ≥5 cm DBH were measured in twenty-five 20 m × 20 m subplots. A total of 57 tree species belonging to 26 families were identified in the three forest types. The UDF had the highest basal area (30 m2 ha−1, followed by the LDF (17 m2 ha−1 and the HDF (13.0 m2 ha−1. The UDF also had the highest tree density (751 individuals ha−1 while the HDF held the lowest (478 individuals ha−1. Across all species, there were 417 “juveniles,” 267 “subadults,” and 67 “adults” in the UDF, while 274 “juveniles,” 230 “subadults,” and 36 “adults” were recorded in the LDF. 238 “juveniles,” 227 “subadults,” and 13 “adults” were obtained in the HDF. The univariate and bivariate data with pair- and mark-correlation functions of intra- and interspecific interactions of the five most abundant species changed in the three forest types. Most species indicated clumping or regular distributions at small scale, but a high ratio of negative interspecific small-scale associations was recorded in both the LDF and HDF sites. These were, however, rare in the UDF.

  7. Chemistry is Evergreen

    Indian Academy of Sciences (India)

    Srimath

    RESONANCE ⎜ March 2009. GENERAL ⎜ ARTICLE. Keywords. Green fluorescent protein,. FRET. Chemistry is Evergreen. 2008 Nobel Prize in Chemistry. Swagata Dasgupta. Swagata Dasgupta is an. Associate Professor in the. Department of Chemistry at IIT Kharagpur. Her research interests revolve around proteins and ...

  8. Guanaco’s diet and forage preferences in Nothofagus forest environments of Tierra del Fuego, Argentina

    Energy Technology Data Exchange (ETDEWEB)

    Quinteros, C.P.; Bava, J.; Gobbi, M.E.; Defossé, G.E.

    2017-11-01

    Aim of study: Guanaco (Lama guanicoe Müller), is a South American native ungulate widely distributed in Patagonia, which in the island of Tierra del Fuego (TF), extends its habitat into Nothofagus spp. forests. Within these forests, guanacos consume lenga (Nothofagus pumilio) leaves and twigs, and other understory species. The aim of this work was to determine: 1) the spring and summer diet of free ranging guanacos, and 2) which plants, grown in the forest understory, guanacos do prefer, or avoid, in these seasons of great forage abundance. Area of study: Tierra del Fuego (Argentina), on three representative areas which combined Nothofagus forests and adjacent meadows (vegas). Material and Methods: uanacos’ diet was determined by comparing epidermal and non-epidermal plant fragments with micro-histological analyses of feces. The analysis was made from composite samples of fresh feces, collected at the seasons of maximum forage productivity (spring and summer). Main results: During spring, 48% of guanacos’ diet was composed of lenga leaves, 30% of grass-like species, 15% of grasses, and less than 7% of herbs, shrubs, and lichens. In summer, 40% of the diet was composed of grasses, 30% of lenga leaves, 25% of grass-like species and the rest corresponded to herbs, shrubs, and lichens. Within the forest understory, guanaco selected lenga leaves and twigs, grass species were consumed according to their availability (or sometimes rejected), while other herbs were not consumed at all. Research highlights: Guanacos’ consumption preference for lenga, even considering the high availability of other forages, could adversely affect forest regeneration.

  9. Ecophysiology of two Sonoran Desert evergreen shrubs during extreme drought

    Science.gov (United States)

    Recent drought across the arid Southwest US may be especially problematic for evergreen desert species that maintain leaves through dry periods. In July, 2002 we compared the ecophysiogical performance of the microphyllous creosotebush (Larrea tridentata) to broadleaved jojoba (Simmondisa chinensis...

  10. Do seasonal profiles of foliar pigments improve species discrimination of evergreen coastal tree species in KwaZulu- Natal, South Africa?

    CSIR Research Space (South Africa)

    Van Deventer, Heidi

    2013-04-01

    Full Text Available pigments, as well as improve species discrimination. This study investigated the potential of seasonal pigment profiles (for foliar carotenoid and total chlorophyll) in improving species discrimination for trees using leaf spectral data. Our aims were to (i...

  11. Soil fauna abundance and diversity in a secondary semi-evergreen forest in Guadeloupe (Lesser Antilles): influence of soil type and dominant tree species

    OpenAIRE

    Loranger-Merciris, Gladys; Imbert, Daniel; Bernhard-Reversat, France; Ponge, Jean-François; Lavelle, Patrick

    2007-01-01

    International audience; The importance of secondary tropical forests regarding the maintenance of soil fauna abundance and diversity is poorly known. The aims of this study were (1) to describe soil fauna abundance and diversity and (2) to assess the determinants of soil fauna abundance and diversity in two stands of a tropical semi-evergreen secondary forest. Soil macrofauna and microarthropod abundance and soil macrofauna diversity were described at two sites developed on different soils an...

  12. Complex adjustments of photosynthetic potentials and internal diffusion conductance to current and previous light availabilities and leaf age in Mediterranean evergreen species Quercus ilex.

    Science.gov (United States)

    Niinemets, Ulo; Cescatti, Alessandro; Rodeghiero, Mirco; Tosens, Tiina

    2006-06-01

    Mature non-senescent leaves of evergreen species become gradually shaded as new foliage develops and canopy expands, but the interactive effects of integrated light during leaf formation (Q(int)G), current light (Q(int)C) and leaf age on foliage photosynthetic competence are poorly understood. In Quercus ilex L., we measured the responses of leaf structural and physiological variables to Q(int)C and Q(int)G for four leaf age classes. Leaf aging resulted in increases in leaf dry mass per unit area (M(A)), and leaf dry to fresh mass ratio (D(F)) and decreases in N content per dry mass (N(M)). N content per area (N(A)) was independent of age, indicating that decreases in N(M) reflected dilution of leaf N because of accumulation of dry mass (NA = N(M) M(A)). M(A), D(F) and N(A) scaled positively with irradiance, whereas these age-specific correlations were stronger with leaf growth light than with current leaf light. Area-based maximum ribulose 1,5-bisphosphate carboxylase/oxygenase (Rubisco) carboxylase activity (V(cmax)A), capacity for photosynthetic electron transport (J(max)A) and the rate of non-photorespiratory respiration in light (R(d)A) were also positively associated with irradiance. Differently from leaf structural characteristics, for all data pooled, these relationships were stronger with current light with little differences among leaves of different age. Acclimation to current leaf light environment was achieved by light-dependent partitioning of N in rate-limiting proteins. Mass-based physiological activities decreased with increasing leaf age, reflecting dilution of leaf N and a larger fraction of non-photosynthetic N in older leaves. This resulted in age-dependent modification of leaf photosynthetic potentials versus N relationships. Internal diffusion conductance (g(m)) per unit area (g(m)A) increased curvilinearly with increasing irradiance for two youngest leaf age classes and was independent of light for older leaves. In contrast, g(m) per dry

  13. How Do Evergreens Stay Ever-Green? Hands on Science.

    Science.gov (United States)

    Kepler, Lynne

    1993-01-01

    Provides instructional techniques, using samples from evergreen trees, to explain to school children the concept of adaptation. The techniques help children develop skills in observation, classification, communication, inferring, and predicting. A teacher's reproducible is included. (GLR)

  14. Efecto de la cobertura y de la fertilización en el desarrollo de plantas de Nothofagus alessandrii cultivadas en contenedor

    OpenAIRE

    Santelices, Rómulo; Navarro Cerrillo, Rafael M.; Drake Aranda, Fernando; Mena, Carlos

    2011-01-01

    Nothofagus alessandrii is an endangered species. Yet, available information for the propagation and nursery cultivation of this species is conspicuously lacking. To this end, we studied the effect of cover and fertilization on early growth of nursery seedlings over one growing season. Using a split plot experimental design with completely random fixed-effect blocks we monitored seedling growth with three levels of shade (plastic net Raschel® of 35, 50, y 80 %) and three doses of slow...

  15. Evidence of Pliocene Nothofagus in Antarctica from Pliocene marine sedimentary deposits (DSDP Site 274)

    Science.gov (United States)

    Fleming, R.F.; Barron, J.A.

    1996-01-01

    Microfossil assemblages in Pliocene sediments from DSDP Site 274 (68??59.81???S, 173??25.64???E) provide data on the age of the sediments and suggest the presence of Nothofagus (southern beech) in Antarctica during the Pliocene. A suite of 17 samples was collected in an interval from Samples 28-274-6R-1, 83-87 cm to 28-274-11R-4, 73-77 cm (48.33-100.29 mbsf). Biostratigraphic study of the abundant diatom assemblages combined with published radiolarian data indicates that the sample interval ranges in age from 5.0 to 2.2 Ma, with an apparent unconformity between about 3.8 and 3.2 Ma. Nothofagidites (the genus for fossil pollen referable to Nothofagus) occurs throughout the interval, as well as pollen and spores with known stratigraphic ranges that unequivocally indicate reworking from older rocks. Species of Nothofagidites recovered include N. asperus, N. brachyspinulosus, N. flemingii, N. senectus, and N. sp. cf. N. lachlaniae; the latter form is previously known from the Sirius Group in the Transantarctic Mountains. Abundant palynomorphs were recovered in only three of the samples from Site 274 (Samples 28-274-9R-2, 15-19 cm; 28-274-9R-2, 48-52 cm; and 28-274-9R-2, 65-69 cm). Based on the diatom and radiolarian biostratigraphic data, the ages of these samples range from 3.00 to 3.01 Ma. The relative abundance of N. sp. cf. N. lachlaniae in the three samples is an order of magnitude higher than relative abundances for the other species of Nothofagidites in the same samples. The significantly higher relative abundance of N. sp. cf. N. lachlaniae suggests that this pollen was derived from trees of Nothofagus that were living in Antarctica during the mid Pliocene. Diatom assemblages from these three samples indicate that sediments in this interval were rapidly deposited as biogenic oozes in an open-ocean setting relatively free of sea ice, thus decreasing the possibility of reworking from a single source bed rich in N. sp. cf. N. lachlaniae. Clearly, more detailed

  16. Tree dynamics in canopy gaps in old-growth forests of Nothofagus pumilio in Southern Chile

    NARCIS (Netherlands)

    Fajardo, Alex; Graaf, de N.R.

    2004-01-01

    The gap dynamics of two Nothofagus pumilio (lenga) stands have been investigated. We evaluated and compared tree diameter distributions, spatial patterns, tree fall and gap characteristics and regeneration responses in gaps in two old-growth forests of Nothofagus pumilio in Southern Chile

  17. Variabilidad topográfica y edáfica en bosques de Nothofagus betuloides (Mirb Blume, en el suroeste de Tierra del Fuego, Chile Edaphic and topographic variability in Nothofagus betuloides (Mirb Blume forests, in southwestern Tierra del Fuego, Chile

    Directory of Open Access Journals (Sweden)

    OSCAR THIERS

    2007-06-01

    Full Text Available Se investigó la variabilidad de las relaciones topográficas y edáficas en sitios con presencia de Nothofagus betuloides y especies arbóreas asociadas en el suroeste de Tierra del Fuego. Estas relaciones se analizaron con métodos estadísticos bivariados y multivariados. Las relaciones del suelo con la topografía estarían fuertemente ligadas a características climáticas (temperatura y humedad de los sitios. Los suelos más fértiles por su mayor profundidad y mejor drenaje, se ubicaron en terrenos de menor elevación (We examined the topographic and edaphic variability of sites dominated by Nothofagus betuloides and associated tree species in southwestern Tierra del Fuego. Edaphic and topographic characteristics were analyzed using bivariate and multivariate statistical methods. The relationships between soil and topography were strongly related to climatic characteristics (temperature and humidity of different sites. Soils with the highest degree of fertility, deep and well drained, were located at the lowest elevations (< 150-200 m and had gentle slopes (< 5 %. Pure forests of N. betuloides occurred in a wide topographic range with high soil variation. The different associations of N. betuloides, with the species N. pumilio, N. antárctica and Drimys winteri, occupy more specific site conditions. Nothofagus betuloides - N. pumilio occurred mostly in the most favorable sites with fertile soils. Nothofagus betuloides - N. antárctica occurred at higher elevations, and steeper slopes, characterized by very thin soils. Nothofagus betuloides - D. winteri occurred in coastal lowlands, with greater humidity and heavier rainfall, and deep soils with limited drainage

  18. Mistletoes and epiphytic lichens contribute to litter input in Nothofagus antarctica forests

    Science.gov (United States)

    Soler, Rosina; Pastur, Guillermo Martínez; Lencinas, María Vanessa; Peri, Pablo Luis

    2015-10-01

    Litter input is one of the key components that define nutrient cycling in forests and the majority of studies only consider the tree components of litterfall. However, epiphytic species can play a crucial role in litter input throughout the growing season. This work evaluates changes in litter production by mistletoe (Misodendrum sp.) and epiphytic lichen (Usnea sp.), related to crown cover in mature unmanaged, second-growth and managed (thinned for silvopastoral use) forests in Tierra del Fuego (Argentina). We used plastic traps to collect litterfall biomass from trees, lichens and mistletoes on a monthly basis over three consecutive years. Tree litter was considerable during autumn (March to May), which is typical of Nothofagus deciduous species in the Southern hemisphere. In contrast, peak litterfall from mistletoes and lichens occurred during spring and summer seasons. Tree litter (1954-3398 kg dry matter ha-1 year-1) was correlated with crown cover gradient being highest in second-growth forests and lowest in thinned sites. While litter input from mistletoes did not vary among forest types (307-333 kg dry matter ha-1 year-1), lichen litter (11-40 kg dry matter ha-1 year-1) was higher in unmanaged and thinned mature forests despite differences in tree crown cover. Contrary to what we expected, the management practices investigated here did not affect the biomass of canopy communities compared to unmanaged mature forests. Mistletoes and lichens significantly increased the spatial (forest type) and temporal complexity (extended period of falling) of litterfall in Nothofagus antarctica forests. This study provides a starting point to understand the ecological relevance of canopy communities in the Patagonian forests of southern Argentina.

  19. Patrones de infestación por insectos xilófagos en renovales de Nothofagus obliqua Mirb. y Nothofagus dombeyi (Mirb. Oerst. (Fagales: Nothofagaceae Infestation patterns of xylophagous insects in second growth stands of Nothofagus obliqua Mirb. and Nothofagus dombeyi (Mirb. Oerst. (Fagales: Nothofagaceae

    Directory of Open Access Journals (Sweden)

    LORENA H. SUÁREZ

    2005-03-01

    Full Text Available Evaluamos los patrones de infestación por insectos xilófagos en renovales de Nothofagus obliqua y Nothofagus dombeyi en las provincias de Valdivia, Osorno y Llanquihue (Chile. Realizamos los análisis a dos escalas: en primer lugar se consideraron las variables diámetro a la altura del pecho (DAP y clase de copa del árbol hospedante (CC como predictores de daño por xilófagos a nivel del árbol. En segundo lugar se consideraron las variables densidad arbórea total, densidad de hospedante, número y cobertura de especies (estas últimas agrupadas en los estratos arbóreo, arbustivo, de herbáceas y de epífitas, y su asociación con el porcentaje de infestación a nivel de rodal. El área de estudio presentó una infestación promedio de 9,35 % en N. obliqua y 15,89 % en N. dombeyi. A nivel individual tanto el DAP como la CC se relacionan positivamente con la presencia de daño, sin embargo el DAP resultó mejor predictor tanto para N. obliqua como para N. dombeyi, aumentando la probabilidad de encontrar un árbol dañado con el aumento del DAP. A nivel de rodal se encontró que las variables estudiadas no se relacionan con la infestación en N. obliqua, mientras que en N. dombeyi renovales con mayor número de especies en el estrato arbustivo y/o con mayor densidad de rodal y hospedante presentaron menores niveles de infestaciónInfestation patterns of xylophagous insects were evaluated in second growth stands of Nothofagus obliqua and Nothofagus dombeyi in Valdivia, Osorno and Llanquihue provinces of Chile. The analysis addressed two scales. First, at the individual level, diameter at breast height (DBH and canopy class (CC of the host tree were used as predictor traits of xylophagous damage. Second, at the stand level, variables such as total tree density, host density, species richness and cover (arboreal, shrubby, herbaceous and epiphytic strata and their asociation with infestation average were considered. The infestation mean was 9

  20. Contrasting ozone sensitivity in related evergreen and deciduous shrubs

    Energy Technology Data Exchange (ETDEWEB)

    Calatayud, Vicent, E-mail: vicent@ceam.e [Fundacion CEAM, c/ Charles R. Darwin 14, Parque Tecnologico, 46980 Paterna, Valencia (Spain); Marco, Francisco; Cervero, Julia [Fundacion CEAM, c/ Charles R. Darwin 14, Parque Tecnologico, 46980 Paterna, Valencia (Spain); Sanchez-Pena, Gerardo [SPCAN, Dir. Gral. de Medio Natural y Politica Forestal, Ministerio de Medio Ambiente, y Medio Rural y Marino, Rios Rosas 24, 28003 Madrid (Spain); Sanz, Maria Jose [Fundacion CEAM, c/ Charles R. Darwin 14, Parque Tecnologico, 46980 Paterna, Valencia (Spain)

    2010-12-15

    Plant responses to enhanced ozone levels have been studied in two pairs of evergreen-deciduous species (Pistacia terebinthus vs. P. lentiscus; Viburnum lantana vs. V. tinus) in Open Top Chambers. Ozone induced widespread visible injury, significantly reduced CO{sub 2} assimilation and stomatal conductance (g{sub s}), impaired Rubisco efficiency and regeneration capacity (V{sub c,max,}J{sub max}) and altered fluorescence parameters only in the deciduous species. Differences in stomatal conductance could not explain the observed differences in sensitivity. In control plants, deciduous species showed higher superoxide dismutase (SOD) activity than their evergreen counterparts, suggesting metabolic differences that could make them more prone to redox imbalances. Ozone induced increases in SOD and/or peroxidase activities in all the species, but only evergreens were able to cope with the oxidative stress. The relevancy of these results for the effective ozone flux approach and for the current ozone Critical Levels is also discussed. - Mediterranean evergreen shrubs have a constitutively higher capacity to tolerate ozone stress than their deciduous relatives.

  1. Effects of micro-topographies on stand structure and tree species diversity in an old-growth evergreen broad-leaved forest, southwestern Japan

    Directory of Open Access Journals (Sweden)

    Tran Van Do

    2015-07-01

    Full Text Available Stand structure and species diversity were studied in correspondence with micro-topographies in an old-growth forest in southwestern Japan. The study was conducted in a 200×200m2 permanent plot, which were divided into 400 subplots using grids of 10m×10m. Subplots were categorized to four micro-topographies as crest slope (CS, head hollow (HH, upper slope (US and lower slope (LS, basing on slope of forest floor and plot position, and to two elevational zones as below 450 m and above 450 m. Tree censuses for all individuals with diameter at breast height (DBH ⩾ 5 cm were conducted in 2009 and 2013. The results indicated that CS had subplot means of living stems, dead stems, DBH, basal area (G, and basal area increment (▵G significantly higher than that in LS. While, means of recruited stems and Shannon diversity index were significantly lower. Comparing between below and above 450 m elevational zones indicated the significantly higher parameters of stand structure and species diversity in above 450 m elevational zone. The differences of edaphic conditions led to difference of density of living stems, species density, DBH, G, and ▵G among micro-topographies. Therefore, crest slope, upper slope, and higher elevational zones should be encouraged for the purposes of carbon accumulation and storage. While, the lower elevational zones should be used for the purposes of species diversity conservation.

  2. Chemical and Antioxidant Properties of Wild Edible Mushrooms from Native Nothofagus spp. Forest, Argentina.

    Science.gov (United States)

    Toledo, Carolina V; Barroetaveña, Carolina; Fernandes, Ângela; Barros, Lillian; Ferreira, Isabel C F R

    2016-09-08

    This study addresses issues regarding chemical and bioactive properties of nine wild edible mushrooms from native Nothofagus forest from Patagonia, Argentina. Macronutrients, sugars, fatty acids, tocopherols, organic acids, phenolic compounds and antioxidant properties were determined. Protein was found in high levels and varied between 3.35 g/100 g dw in Cyttaria hariotii and 22.29 g/100 g dw in Lepista nuda. All of them presented mannitol and trehalose as main sugars. Mannitol was significantly higher in Ramaria patagonica, although absent in Fistulina endoxantha, whereas trehalose predominated in Aleurodiscus vitellinus, Hydropus dusenii, Cortinarius magellanicus, C. hariotii, Grifola gargal and L. nuda, ranging from 1.15 to 10.26 g/100 g dw; it was absent in R. patagonica. The major fatty acid found was linoleic acid, followed by oleic acid and palmitic acid. All species presented oxalic and fumaric acids, while some also had malic, quinic and citric acids. Tocopherols composition was variable. Cortinarius magellanicus presented significantly higher contents of both α-tocopherol and β-tocopherol. R. patagonica presented the best results in all the antioxidant activity assays (EC50 values ≤ 1 mg/mL) and the highest content of phenolic compounds presenting gallic, p-hydroxybenzoic, p-coumaric and cinnamic acids. This study constitutes the first report on chemical composition and nutritional value of most of these edible mushroom species. Furthermore, it provides important information necessary to characterize and define the use of these species as gastronomic delicacies, functional foods and sources of bioactive compounds.

  3. POLLINATION ECOLOGY OF TARENNA ASIATICA (L. KUNTZ EX. K. SCHUM. (RUBIACEAE, A KEYSTONE EVERGREEN SHRUB SPECIES IN THE EASTERN GHATS FOREST - ANDHRA PRADESH, INDIA

    Directory of Open Access Journals (Sweden)

    A. Jacob Solomon Raju

    2016-03-01

    Full Text Available Tarenna asiatica flowers throughout the year with profuse flowering during december-april. the flowers are hermaphroditic, self- and cross-compatible, protandrous, nectariferous and entomophilous. the mating system is facultatively xenogamous with highest fruit set in xenogamy. The protandry facilitates autonomous selfing. Bees and butterflies effect both self- and cross-pollinations. Fruits mature within a short period and the fallen seeds germinate following monsoon rains in June-July. a dearth of floral resources exists during december-april period; T. asiatica with profuse flowering during this period plays a key role to provide pollen and nectar for the probing flower foragers and hence is considered to be a keystone species in the eastern Ghats forest

  4. Xanthophyllomyces dendrorhous (Phaffia rhodozyma on stromata of Cyttaria hariotii in northwestern Patagonian Nothofagus forests

    Directory of Open Access Journals (Sweden)

    Diego Libkind

    2011-09-01

    Full Text Available The occurrence and distribution of Xanthophyllomyces dendrorhous associated with Cyttaria hariotii parasitizing three Nothofagus species (N. dombeyi, N. antarctica and N. pumilio in northwestern Patagonia (Argentina, as well as the factors that may affect this distribution were herein studied. Between 2000 and 2007, samples were obtained from 18 different locations. Based on physiological tests and morphological characteristics of sexual structures, 72 isolates were identified as X. dendrorhous. Representative strains were studied by MSP-PCR fingerprinting and sequence analysis of the ITS region. MSP-PCR fingerprints were similar for the newly isolated strains, and were also identical to the profiles of the strains previously found in this region. Patagonian strains appear to be a genetically uniform and distinct population, supporting the hypothesis that the association with different host species has determined genetically distinct X. dendrorhous populations worldwide. X. dendrorhous was recovered from N. dombeyi and N. antarctica. Approximately half the sampling sites and samples were positive for X. dendrorhous, but the isolation recovery rate was low. X. dendrorhous was absent in the early stages of ascostromata maturation, becoming more abundant in later stages. The present work represents a step forward in the understanding of the natural distribution and ecology of this biotechnologically relevant yeast.Xanthophyllomyces dendrorhous (Phaffia rhodozyma asociado a estromas de Cyttaria hariotii en bosques de Nothofagus en el noroeste de la Patagonia. Se estudió la ocurrencia y la distribución de Xanthophyllomyces dendrorhous asociado a Cyttaria hariotii en tres especies de Nothofagus (N. dombeyi, N. antarctica y N. pumilio del noroeste de la Patagonia (Argentina, y los factores que podrían afectar esta distribución. El muestreo se realizó entre 2000 y 2007 en 18 sitios diferentes. Según las pruebas fisiológicas y las caracter

  5. Xanthophyllomyces dendrorhous (Phaffia rhodozyma) on stromata of Cyttaria hariotii in northwestern Patagonian Nothofagus forests.

    Science.gov (United States)

    Libkind, Diego; Tognetti, Celia; Ruffini, Alejandra; Sampaio, José Paulo; Van Broock, María

    2011-01-01

    The occurrence and distribution of Xanthophyllomyces dendrorhous associated with Cyttaria hariotii parasitizing three Nothofagus species (N. dombeyi, N. antarctica and N. pumilio) in northwestern Patagonia (Argentina), as well as the factors that may affect this distribution were herein studied. Between 2000 and 2007, samples were obtained from 18 different locations. Based on physiological tests and morphological characteristics of sexual structures, 72 isolates were identified as X. dendrorhous. Representative strains were studied by MSP-PCR fingerprinting and sequence analysis of the ITS region. MSP-PCR fingerprints were similar for the newly isolated strains, and were also identical to the profiles of the strains previously found in this region. Patagonian strains appear to be a genetically uniform and distinct population, supporting the hypothesis that the association with different host species has determined genetically distinct X. dendrorhous populations worldwide. X. dendrorhous was recovered from N. dombeyi and N. antarctica. Approximately half the sampling sites and samples were positive for X. dendrorhous, but the isolation recovery rate was low. X. dendrorhous was absent in the early stages of ascostromata maturation, becoming more abundant in later stages. The present work represents a step forward in the understanding of the natural distribution and ecology of this biotechnologically relevant yeast.

  6. Regeneración de un bosque mixto de Nothofagus (Nothofagaceae después de una corta selectiva Regeneration of a Nothofagus (Nothofagaceae mixed forest after selective cutting

    Directory of Open Access Journals (Sweden)

    ALEJANDRO DEZZOTTI

    2003-12-01

    Full Text Available El estudio de la ecología de la regeneración natural del bosque constituye una parte esencial de la silvicultura. El cerro Tren Tren (40°12' S, 71°26' O, 1.367 m, Reserva Mapuche Curruhuinca, Argentina está ocupado por un bosque cerrado compuesto por Nothofagus dombeyi, N. nervosa y N. obliqua. En 1994 se estimó la densidad de renovales (diámetro en la base del tallo Understanding forest regeneration is essential to develop sound, ecologically-based silvicultural practices. Mount Tren Tren (40°12' S, 71°26' W, 1,367 m, Reservation Mapuche Curruhuinca, Argentina is occupied by a closed stand of Nothofagus dombeyi, N. obliqua, and N. nervosa. In 1994, tree regeneration (root collar diameter < 10 cm was estimated to be 90 ind ha-1. After that, a group selection silvicultural system was implemented and the resulting 10 artificial gaps of between 1,587 and 4,322 m² were enclosed to prevent grazing by domestic livestock. Size and age structure of regeneration were analysed based on systematic and random samplings. All tree species became established simultaneously within the artificial gaps. However, the less light demanding N. nervosa exhibited a mean age slightly larger given its differential persistence as "advanced regeneration" previous to cutting treatment. Tree regeneration was estimated in 97,006 ind ha-1 (68 % of N. dombeyi, 20 % of N. obliqua, and 12 % of N. nervosa. Regeneration abundance and composition were unrelated to shape and size of regeneration gaps, nor to abundance of adult trees within the stand and along the gap boundaries. A significant positive effect of the enclosure on plant was observed. The 86 % of juvenile Nothofagus were present when understory height and cover were low to intermediate. The management plan is considered adequate if the abundance of regeneration is compared before and after its implementation, and encourages the use and conservation of this forest type under the current silvicultural system

  7. Calcium and boron for in vitro rooting of Nothofagus nervosa.

    Science.gov (United States)

    Martínez Pastur, G M; Arena, M; Curvetto, N

    2000-04-01

    Several mineral compounds influence adventitious rooting, and those containing boron and calcium, play an important role. They are associated to the enzyme regulation, cell division, cellular metabolism (induction stage) and roots enlargement (expression stage). The aims of this work were to study the variation of the endogenous calcium and boron concentrations along the rooting, and determine their optimal concentrations in the rooting basal medium of Nothofagus nervosa. Significant variation in endogenous calcium concentrations was detected along the rooting phase, strongly correlated with rhizogenesis phenomenons and linked to total peroxidase variation as cited elsewhere. Calcium and boron concentrations in the basal medium significantly affected the rooting. Treatment containing 60 mg.L-1 Ca and 1 mg.L-1 B produced root formation in fewer days than other combinations. The variation of these nutrient concentrations in the medium is a useful tool to improve microcutting rooting. Roots are obtained earlier and in a shorter period of time, finally resulting in more homogeneous microplants with a better developed rooting system.

  8. Diferencias en la flora herbácea y arbustiva entre claros y áreas bajo dosel en un bosque de Nothofagus pumilio en Argentina Differences in the herb and shrub flora growing under canopy gaps and under closed canopies in a Nothofagus pumilio forest of Argentina

    Directory of Open Access Journals (Sweden)

    M. ANGÉLICA DAMASCOS

    2002-09-01

    Full Text Available Se comparó la distribución de las hierbas y arbustos bajo el dosel y en dos tamaños de claros del bosque deciduo de Nothofagus pumilio de Argentina. La riqueza total y promedio de especies por cuadrado fueron similares bajo el dosel y en los claros pequeños (diámetro mayor The distribution of herbs and shrubs under closed canopies and in two canopy gaps of different size was compared in a Nothofagus pumilio deciduous forest of Argentina. The total and the average species richness per plot were similar between the areas under the canopy and in small (maximum diameter < 5 m and medium size gaps (maximum diameter 5-10 m. Generalist species were the most numerous (46 %, while obligate and facultatively shade-tolerant (heliophobous and intolerant (heliophilous species accounted for 19 and 15 % of the species, respectively. The absence of differences in species richness may be attributed to: (1 high frequency of generalist species (2 low effect of gap formation on shade-tolerant species distribution, (3 persistence of facultatively shade-tolerant species in small gaps, (4 gap invasion by obligate shade-intolerant species. The heterogeneity of light environment beneath the canopy and the effects on gap microclimate of edge trees and gap shrubs are possible causes of these patterns. Although with variations between the different biological groups, forest species are probably tolerant to the low level of disturbance generated by the natural forest dynamics

  9. Site quality influence over understory plant diversity in old-growth and harvested Nothofagus pumilio forests

    Energy Technology Data Exchange (ETDEWEB)

    Gallo, E. A.; Lencinas, M. V.; Martinez-Pastur, G. J.

    2013-05-01

    Aim of study: The effects and interactions of shelter wood forest harvesting and site qualities over understory plant species diversity and composition were compared among primary and harvested Nothofagus pumilio forests. Area of study: Tierra del Fuego (Argentina), on three pure conditions (one and six year-old harvested, and primary without previous harvesting forests) and three site qualities (high, medium and low). Material and Methods: Understory richness and cover (%) were registered in five replicates of 1 hectare each per treatment. Taxonomic species were classified in categories (groups, origin and life forms). Two-way ANOVAs and multivariate analyses were conducted. Main results: Shelterwood harvesting and site quality significantly influenced understory cover and richness, which allow the introduction of native and exotic species and increasing of dicot and monocot covers. In dicots, monocots, exotics and total groups, higher richness and covers were related to time. Meanwhile, cover reached similar high values in all site qualities on dicot, native and total groups. On the other hand, monocot and exotic richness and cover remain similar in primary and recently harvested forests, and greatly increased in old harvested forests. Mosses and ferns were among the most sensitive groups. Research highlights: Impacts of shelterwood cut depend on site quality of the stands and time since harvesting occurs. For this, different site quality stands should received differential attention in the development of conservation strategies, as well as variations in the shelterwood implementation (as irregularity and patchiness) should be considered to better promote understory plant species conservation inside managed areas. (Author) 45 refs.

  10. [Frost-resistance of subtropical evergreen woody plants: an evaluation based on plant functional traits].

    Science.gov (United States)

    Xu, Yi-Lu; Yang, Xiao-Dong; Xu, Yue; Xie, Yi-Ming; Wang, Liang-Yan; Yan, En-Rong

    2012-12-01

    Evaluating the frost-resistance of evergreen woody plants is of significance in guiding the species selection in forest management in subtropical region. In this paper, an investigation was made on the functional traits (including specific leaf area, stem wood density, leaf area, leaf dry matter content, leaf relative electrical conductance, and twig wood density) of 64 common evergreen broad-leaved and coniferous woody plant species in the Ningbo region of Zhejiang Province, East China, after a severe snowstorm in early 2008, aimed to select the evergreen woody plants with high ability of freeze-tolerance, and to establish a related evaluation system. By using a hierarchy analysis approach, the weight values of the functional traits of each species were determined, and an index system for evaluating the plants tolerance ability against freeze and mechanical damage was established. Based on this system, 23 evergreen plant species with high tolerance ability against freeze and mechanical damage, such as Cyclobalanopsis gilva, Cyclobalanopsis nubium, Neolitsea aurata, and Vacciniuim mandarinorum, were selected. In the meantime, on the basis of the ordering with each of the functional traits, the ordering of the tolerance ability of the 64 plant species against freeze and mechanical damage was made, and a list for the frost-resistance ability of the subtropical evergreen woody plant species in Ningbo region was constituted.

  11. Evergreen sclerophyllous Quercus forests in northwestern Yunnan, China as compared to the Mediterranean evergreen Quercus forests in California, USA and northeastern Spain

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    C. Q. Tang

    2006-12-01

    Full Text Available Evergreen sclerophyllous Quercus forests in NW Yunnan (China were studied and compared with the Mediterranean evergreen sclerophyllous Quercus forests in central coastal California (USA and Catalonia (NE Spain. Forests of Q. aquifolioides, Q. pannosa, Q. longispica of NW Yunnan, Q. agrifolia of California and Q. ilex of NE Spain were analyzed as representative communities. The similarities and differences at the community level in the contemporary vegetation of the sclerophyllous Quercus forest found in the three regions are clarified. The general patterns of the evergreen Quercus forest in the three regions were similar, though different assemblages of species were involved. The species diversity in all three regions was rather low. The species richness did not significantly differ among the forests, although in the Q. longispica forest it is somewhat higher than the others. The three representative species of evergreen Quercus in NW Yunnan reached the greatest maximum height, while Q. agrifolia of California had the largest basal area per ha. The Q. ilex forest of Spain had the lowest values for maximum tree height and dbh and the highest density per ha. Frequency of dbh size classes indicated that Q. aquifolioides, Q. pannosa, and Q. agrifolia had potentially good regeneration of the sporadic type with highest values for the intermediate size classes, and the regeneration of Q. longispica and Q. ilex was strong as indicated by a reverse-J pattern. Still, in each area, most regeneration was from sprouting. In all three regions the evergreen Quercus species have adapted to environmental changes, for instance by development of sprouting and rooting abilities to resist drought, cold conditions and various disturbances. The evergreen Quercus forests in NW Yunnan were structurally more similar to the Q. agrifolia forest of central coastal California than to the Q. ilex forest of NE Spain.

  12. Chemical and Antioxidant Properties of Wild Edible Mushrooms from Native Nothofagus spp. Forest, Argentina

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    Carolina V. Toledo

    2016-09-01

    Full Text Available This study addresses issues regarding chemical and bioactive properties of nine wild edible mushrooms from native Nothofagus forest from Patagonia, Argentina. Macronutrients, sugars, fatty acids, tocopherols, organic acids, phenolic compounds and antioxidant properties were determined. Protein was found in high levels and varied between 3.35 g/100 g dw in Cyttaria hariotii and 22.29 g/100 g dw in Lepista nuda. All of them presented mannitol and trehalose as main sugars. Mannitol was significantly higher in Ramaria patagonica, although absent in Fistulina endoxantha, whereas trehalose predominated in Aleurodiscus vitellinus, Hydropus dusenii, Cortinarius magellanicus, C. hariotii, Grifola gargal and L. nuda, ranging from 1.15 to 10.26 g/100 g dw; it was absent in R. patagonica. The major fatty acid found was linoleic acid, followed by oleic acid and palmitic acid. All species presented oxalic and fumaric acids, while some also had malic, quinic and citric acids. Tocopherols composition was variable. Cortinarius magellanicus presented significantly higher contents of both α-tocopherol and β-tocopherol. R. patagonica presented the best results in all the antioxidant activity assays (EC50 values ≤ 1 mg/mL and the highest content of phenolic compounds presenting gallic, p-hydroxybenzoic, p-coumaric and cinnamic acids. This study constitutes the first report on chemical composition and nutritional value of most of these edible mushroom species. Furthermore, it provides important information necessary to characterize and define the use of these species as gastronomic delicacies, functional foods and sources of bioactive compounds.

  13. Caracterización de suelos bajo bosques de Nothofagus betuloides (Mirb Blume, en Tierra del Fuego, Chile Characterization of soils of Nothofagus betuloides (Mirb Blume forests, in Tierra del Fuego, Chile

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    VÍCTOR GERDING

    2002-12-01

    Full Text Available En tres sectores de la parte occidental de Tierra del Fuego (54º45'-54º15' S, 68º40'-70º10' O se caracterizó morfológica, física y químicamente los suelos bajo bosques de coigüe de Magallanes (Nothofagus betuloides (Mirb Blume y sus especies asociadas lenga (Nothofagus pumilio (P. et E. Krasser y canelo (Drimys winteri Forst.. Se describieron 85 perfiles de suelo y aproximadamente 250 observaciones con bastón pedológico. Los suelos bajo coigüe de Magallanes eran jóvenes, muy influidos por la actividad volcánica, topografía y clima. Se observó la presencia de los órdenes Spodosol e Iceptisol, principalmente. En general los suelos eran delgados a muy delgados (mayoritariamente entre 10 y 40 cm, con un alto volumen de esqueleto, textura franca, estructura masiva a granular, capacidad de agua aprovechable baja y drenaje externo e interno moderado a lento. Además, presentan una alta acidez (pH 4-5,5, una baja oferta nutricional y muy altos niveles de saturación de aluminio (promedio > 60 %. El mantillo (Oe/Oa presentó condiciones adecuadas para el desarrollo radicular. Existe comúnmente un horizonte blanco (frecuentemente 10 YR 5/1-2 inmediatamente debajo del mantillo, con textura franco limosa y estructura masiva, con arraigamiento muy bajo. Se plantea como hipótesis que este horizonte se originó por depósitos de cenizas volcánicas y procesos de podzolización. Se concluye que la fertilidad de estos suelos es baja debido a limitantes físicas (dificultades de arraigamiento y químicas (acidez, toxicidad de aluminio, baja oferta de basesSoils under coigüe de Magallanes (Nothofagus betuloides (Mirb Blume forests, located in the oriental part of Tierra del Fuego (54º45'-54º15' S, 68º40'-70º10' W, were characterized morphologically, physically and chemically. Associated tree species were lenga (Nothofagus pumilio (P. et E. Krasser and canelo (Drimys winterii Forst.. A total of 85 soil profiles and approximately 250 soil

  14. Winter-Deciduous versus Evergreen Habit in Mediterranean Regions: A Model

    Science.gov (United States)

    Mark A. Blumler

    1991-01-01

    Although winter-deciduous species are presumed to be "out-of-phase" with the mediterranean climate regime, distributional evidence suggests some taxa may be more tolerant of summer drought than evergreen sclerophylls. Deciduous species possess several features that confer advantage in extreme summer dry regions: drought-deciduousness, an efficient response to...

  15. Artocarpus hirsutus Lam. of Moraceae is a large evergreen tree with ...

    Indian Academy of Sciences (India)

    Artocarpus hirsutus Lam. of Moraceae is a large evergreen tree with milky latex. This species occurs wild and is also cultivated for its fruit, which is edible. Leaves are simple and dark green. The branchlets are covered with rust-brown hairs. Inflorescence is axillary. The female inflorescence is globose with individualjlowers ...

  16. Deciduous and evergreen trees differ in juvenile biomass allometries because of differences in allocation to root storage.

    Science.gov (United States)

    Tomlinson, Kyle W; van Langevelde, Frank; Ward, David; Bongers, Frans; da Silva, Dulce Alves; Prins, Herbert H T; de Bie, Steven; Sterck, Frank J

    2013-08-01

    Biomass partitioning for resource conservation might affect plant allometry, accounting for a substantial amount of unexplained variation in existing plant allometry models. One means of resource conservation is through direct allocation to storage in particular organs. In this study, storage allocation and biomass allometry of deciduous and evergreen tree species from seasonal environments were considered. It was expected that deciduous species would have greater allocation to storage in roots to support leaf regrowth in subsequent growing seasons, and consequently have lower scaling exponents for leaf to root and stem to root partitioning, than evergreen species. It was further expected that changes to root carbohydrate storage and biomass allometry under different soil nutrient supply conditions would be greater for deciduous species than for evergreen species. Root carbohydrate storage and organ biomass allometries were compared for juveniles of 20 savanna tree species of different leaf habit (nine evergreen, 11 deciduous) grown in two nutrient treatments for periods of 5 and 20 weeks (total dry mass of individual plants ranged from 0·003 to 258·724 g). Deciduous species had greater root non-structural carbohydrate than evergreen species, and lower scaling exponents for leaf to root and stem to root partitioning than evergreen species. Across species, leaf to stem scaling was positively related, and stem to root scaling was negatively related to root carbohydrate concentration. Under lower nutrient supply, trees displayed increased partitioning to non-structural carbohydrate, and to roots and leaves over stems with increasing plant size, but this change did not differ between leaf habits. Substantial unexplained variation in biomass allometry of woody species may be related to selection for resource conservation against environmental stresses, such as resource seasonality. Further differences in plant allometry could arise due to selection for different types

  17. Water uptake of Alaskan tundra evergreens during the winter-spring transition.

    Science.gov (United States)

    Moser, Jonathan G; Oberbauer, Steven F; Sternberg, Leonel da S L; Ellsworth, Patrick Z; Starr, Gregory; Mortazavi, Behzad; Olivas, Paulo C

    2016-02-01

    The cold season in the Arctic extends over 8 to 9 mo, yet little is known about vascular plant physiology during this period. Evergreen species photosynthesize under the snow, implying that they are exchanging water with the atmosphere. However, liquid water available for plant uptake may be limited at this time. The study objective was to determine whether evergreen plants are actively taking up water while under snow and/or immediately following snowmelt during spring thaw. In two in situ experiments, one at the plot level and another at the individual species level, (2)H-labeled water was used as a tracer injected beneath the snow, after which plant stems and leaves were tested for the presence of the label. In separate experiments, excised shoots of evergreen species were exposed to (2)H-labeled water for ∼5 s or 60 min and tested for foliar uptake of the label. In both the plot-level and the species-level experiments, some (2)H-labeled water was found in leaves and stems. Additionally, excised individual plant shoots exposed to labeled water for 60 min took up significantly more (2)H-label than shoots exposed ∼5 s. Evergreen tundra plants take up water under snow cover, some via roots, but also likely by foliar uptake. The ability to take up water in the subnivean environment allows evergreen tundra plants to take advantage of mild spring conditions under the snow and replenish carbon lost by winter respiration. © 2016 Botanical Society of America.

  18. Heterogeneidad estructural y espacial de un bosque mixto dominado por Nothofagus dombeyi después de un disturbio parcial Structural and spatial heterogeneity of a mixed Nothofagus donibeyi-dominate forest stand after a partial disturbance

    Directory of Open Access Journals (Sweden)

    DANIEL P SOTO

    2010-01-01

    ón forestal.The forests dominated by Nothofagus dombeyi are amongst the most abundant and productive forests in the South American temperate region. In the lowlands of Chile Nothofagus dombeyi-dominated secondary forests with their associated tree species are common. Their diameter distribution, spatial patterns and association between species have not been studied. In this work we quantify those patterns and test whether there is a spatial association between species in a structurally complex forest created after a partial disturbance. We established a 70 x 130 m plot (0.91 ha in the Llancahue property near the city of Valdivia (39°48' S, 73°11' W and 150 masl. We quantified the structure and the diameter asymmetry through the Weibull probability function and the asymmetry Índex, respectively. The spatial pattern (random, clustered and regular of the forest and of each species, and the spatial association (indifference, repulsion and attraction of N. dombeyi with the main species were evaluated with the uni-and bivariate Ripley functions. The spatial autocorrelation for the diameter at breast height d was evaluated by means of semivariograms. This paper reports that the size distribution is influenced by some species that either resisted the disturbance or were highly resilient due to their regeneration strategies, which is confirmed by the spatial pattern in aggregates, and a strong spatial autocorrelation for the species. We found that the spatial patterns are intraspecific, and do not affect the spatial association between dominant and subordinated trees species. Finally, we suggest that partial disturbances cause a rapid transformatíon from a simple to a complex structure along forest succession.

  19. 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

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

    Directory of Open Access Journals (Sweden)

    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

  1. An ecological basis for Nothofagus pumilio Forest management in Tierra del Fuego

    OpenAIRE

    Richter, Laura; Frangi, Jorge Luis

    1992-01-01

    Tradicionalmente en la Argentina, la ecología forestal y la silvicultura han marchado en general por caminos separados. La información ecológica apropiada puede ser aprovechada para un mejor manejo del bosque. La especie nativa Nothofagus pumilio (n.v. lenga) y los bosques que forma en la Tierra del Fuego poseen características biológicas y ecológicas favorables y desfavorables para la producción de madera que pueden diferir si son otros los objetivos del manejo. Estas características estruct...

  2. Multi-stemmed trees of Nothofagus pumilio second-growth forest in Patagonia are formed by highly related individuals

    Science.gov (United States)

    Till-Bottraud, Irène; Fajardo, Alex; Rioux, Delphine

    2012-01-01

    Background and Aims Multi-stemmed trees (tree clusters) in Nothofagus pumilio, a dominant tree species in Patagonia, are very uncommon and are restricted to the edge of second-growth forests following human-provoked fires. No vegetative reproduction has been reported so far. The genetic structure of multi-stemmed trees of this species was investigated and it was hypothesized that genets within a cluster were more closely related than average in the population. Methods Fifteen clusters (composed of at least three purported stems) and 15 single trees were sampled at the edge of a second-growth forest and genotyped using two amplified fragment length polymorphism (AFLP) primer pairs. We obtained 119 polymorphic markers that allowed clonality to be determined, together with sibship structure and relatedness among samples. Key Results Clonality was detected in seven clusters but all clusters had at least two different genotypes. Full sibs were found exclusively within clusters and in all clusters. Within a cluster, stems that were not identified as full sibs were often half sibs. Relatedness values for the full sibs and half sibs were higher than the theoretical values of 0·5 and 0·25 but the relatedness between clusters was very low. Conclusions Tree clusters that are merged at the edge of the second-growth forest of N. pumilio are composed of stems of the same genotype and of other genotypes that are highly related (but not always). It is suggested that this peculiar genetic structure results from a combination of several causes, including selection for merging of related individuals. PMID:22782238

  3. Do evergreen and deciduous trees have different effects on net N mineralization in soil?

    Science.gov (United States)

    Mueller, Kevin E; Hobbie, Sarah E; Oleksyn, Jacek; Reich, Peter B; Eissenstat, David M

    2012-06-01

    Evergreen and deciduous plants are widely expected to have different impacts on soil nitrogen (N) availability because of differences in leaf litter chemistry and ensuing effects on net N mineralization (N(min)). We evaluated this hypothesis by compiling published data on net N(min) rates beneath co-occurring stands of evergreen and deciduous trees. The compiled data included 35 sets of co-occurring stands in temperate and boreal forests. Evergreen and deciduous stands did not have consistently divergent effects on net N(min) rates; net N(min) beneath deciduous trees was higher when comparing natural stands (19 contrasts), but equivalent to evergreens in plantations (16 contrasts). We also compared net N(min) rates beneath pairs of co-occurring genera. Most pairs of genera did not differ consistently, i.e., tree species from one genus had higher net N(min) at some sites and lower net N(min) at other sites. Moreover, several common deciduous genera (Acer, Betula, Populus) and deciduous Quercus spp. did not typically have higher net N(min) rates than common evergreen genera (Pinus, Picea). There are several reasons why tree effects on net N(min) are poorly predicted by leaf habit and phylogeny. For example, the amount of N mineralized from decomposing leaves might be less than the amount of N mineralized from organic matter pools that are less affected by leaf litter traits, such as dead roots and soil organic matter. Also, effects of plant traits and plant groups on net N(min) probably depend on site-specific factors such as stand age and soil type.

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

    Science.gov (United States)

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

    2013-01-01

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

  5. The transitional semi-evergreen bushland in Ethiopia

    DEFF Research Database (Denmark)

    van Breugel, Paulo; Friis, Ib; Sebsebe, Demissew

    2016-01-01

    Question: Evergreen bushlands in Ethiopia have been inadequately studied and mapped. We address the question whether there is a transitional semi-ever-green bushland on the eastern escarpment of the Ethiopian Highlands, with unique floristic characteristics that distinguish it from the evergreen...... bushlands in other parts of Ethiopia and eastern Africa. Methods: Based on a review of the recent descriptions of evergreen bushlands in Ethiopia, we hypothesize that there is a distinct zone of natural semi-ever-green bushland, which is restricted to the eastern and southeastern escarpment of the Ethiopian...... Highlands. In contrast, evergreen bushlands in other parts of Ethiopia are considered to be of a secondary nature. To test this hypothesis, we carried out qualitative vegetation surveys in 354 locations across Ethiopia and classified the vegetation in these locations based on the occurrences of indicator...

  6. The seasonality of butterflies in a semi-evergreen forest: Gibbon Wildlife Sanctuary, Assam, northeastern India

    Directory of Open Access Journals (Sweden)

    Arun P. Singh

    2015-01-01

    Full Text Available A study spanning 3.7 years on the butterflies of Gibbon Wildlife Sanctuary GWS (21km2, a semi-evergreen forest, in Jorhat District of Assam, northeastern India revealed 211 species of butterflies belonging to 115 genera including 19 papilionids and seven ‘rare’ and ‘very rare’ species as per Evans list of the Indian sub-continent (Great Blue Mime Papilio paradoxa telearchus; Brown Forest BobScobura woolletti; Snowy Angle Darpa pteria dealbatahas; Constable Dichorragia nesimachus; Grey Baron Euthalia anosia anosia; Sylhet Oakblue Arhopala silhetensis; Branded Yamfly Yasoda tripunctata. The butterflies showed a strong seasonality pattern in this forest with only one significant peak during the post monsoon (September-October when 118 species were in flight inside the forest which slowly declined to 92 species in November-December. Another peak (102 species was visible after winter from March to April. Species composition showed least similarity between pre-monsoon (March-May and post-monsoon (October-November seasons. The number of papilionid species were greater from July to December as compared from January to June. The findings of this study suggest that the pattern of seasonality in a semi-evergreen forest in northeastern India is distinct from that of the sub-tropical lowland forest in the Himalaya. Favourable logistics and rich diversity in GWS points to its rich potential in promoting ‘butterfly inclusive ecotourism’ in this remnant forest.

  7. Fast growth involves high dependence on stored resources in seedlings of Mediterranean evergreen trees

    Science.gov (United States)

    Uscola, Mercedes; Villar-Salvador, Pedro; Gross, Patrick; Maillard, Pascale

    2015-01-01

    Background and Aims The carbon (C) and nitrogen (N) needed for plant growth can come either from soil N and current photosynthesis or through remobilization of stored resources. The contribution of remobilization to new organ growth on a whole-plant basis is quite well known in deciduous woody plants and evergreen conifers, but this information is very limited in broadleaf evergreen trees. This study compares the contribution of remobilized C and N to the construction of new organs in spring, and assesses the importance of different organs as C and N sources in 1-year-old potted seedlings of four ecologically distinct evergreen Mediterranean trees, namely Quercus ilex, Q. coccifera, Olea europaea and Pinus hapelensis. Methods Dual 13C and 15N isotope labelling was used to unravel the contribution of currently taken up and stored C and N to new growth. Stored C was labelled under simulated winter conditions. Soil N was labelled with the fertilization during the spring growth. Key results Oaks allocated most C assimilated under simulated winter conditions to coarse roots, while O. europaea and P. halepensis allocated it to the leaves. Remobilization was the main N source (>74 %) for new fine-root growth in early spring, but by mid-spring soil supplied most of the N required for new growth (>64 %). Current photosynthesis supplied >60 % of the C in new fine roots by mid-spring in most species. Across species, the proportion of remobilized C and N in new shoots increased with the relative growth rate. Quercus species, the slowest growing trees, primarily used currently acquired resources, while P. halepensis, the fastest growing species, mainly used reserves. Increases in the amount of stored N increased N remobilization, which fostered absolute growth both within and across species. Old leaves were major sources of remobilized C and N, but stems and roots also supplied considerable amounts of both in all species except in P. halepensis, which mainly relied on foliage

  8. Manipulation of VOC emissions with methyl jasmonate and carrageenan in the evergreen conifer Pinus sylvestris and evergreen broadleaf Quercus ilex.

    Science.gov (United States)

    Semiz, G; Blande, J D; Heijari, J; Işik, K; Niinemets, U; Holopainen, J K

    2012-03-01

    Plant defence can be induced by exposing plants to the plant hormone jasmonic acid (JA) or its volatile ester, methyl jasmonate (MeJA). Carrageenans (Carr) - sulphated D-galactans extracted from red algae - can also induce plant defences. In this study, the effects of exogenous MeJA and Carr application (concentration 300 and 12.7 μmol, respectively) on volatile emissions from two widespread evergreen woody species, Pinus sylvestris (nine Turkish and one Finnish provenance) and Quercus ilex (Italian provenance) were investigated. We collected headspace samples from seedlings and analysed the quality and quantity of volatile compounds emitted by treated and control plants. In total, 19 monoterpenes, 10 sesquiterpenes, 10 green leaf volatiles (GLVs) and two aromatic compounds were emitted by P. sylvestris from all the provenances studied. Foliar MeJA application clearly affected the volatile profiles of trees from all the provenances. Effects of Carr were genotype specific. In Q. ilex, emissions of sesquiterpenes, GLVs and the homoterpene (E)-DMNT were all induced by MeJA application. However, emissions of most constitutively emitted monoterpenes were significantly reduced. Carr application also led to a significant reduction in monoterpene emissions, but without corresponding increases in other emissions. Our results indicate that exogenously applied MeJA and Carr can both significantly modify the volatile profiles of P. sylvestris and Q. ilex, but also that there are important provenance- and species-specific differences in the overall degree of elicitation and compositions of elicited compounds. © 2011 German Botanical Society and The Royal Botanical Society of the Netherlands.

  9. Two types of matter economy for the wintering of evergreen shrubs in regions of heavy snowfall.

    Science.gov (United States)

    Ino, Yoshio; Maekawa, Tomoyuki; Shibayama, Tomohiro; Sakamaki, Yoshiaki

    2003-08-01

    Plant adaptation to an environment subject to heavy snowfalls was investigated in four species of evergreen shrubs growing in a Fagus crenata forest in an area of Honshu on the Sea of Japan. These shrubs stored carbohydrates in some organs before the snowy season and were covered with snow for 4-5 months. Aucuba japonica var. borealis, Camellia rusticana, and Ilex crenata var. paludosa maintained a reserve of carbohydrates during the snowy season. In Daphniphyllum macropodum var. humile, the reserve of carbohydrates decreased during winter. The respiration rates in the first three species decreased from autumn to winter, whereas the decrease in D. macropodum was slight. It was found that the first three species could use reserve carbohydrates for the growth of new shoots after the thaw, whereas in the last species the growth of new shoots depends on high photosynthetic activity in late spring. Our findings suggest some types of matter economy in evergreen shrubs for wintering in an environment of heavy snow.

  10. Element accumulation patterns of deciduous and evergreen tree seedlings on acid soils: implications for sensitivity to manganese toxicity.

    Science.gov (United States)

    St Clair, Samuel B; Lynch, Jonathan P

    2005-01-01

    Foliar nutrient imbalances, including the hyperaccumulation of manganese (Mn), are correlated with symptoms of declining health in sensitive tree species growing on acidic forest soils. The objectives of this study were to: (1) compare foliar nutrient accumulation patterns of six deciduous (sugar maple (Acer saccharum Marsh.), red maple (Acer rubrum L.), red oak (Quercus rubra L.), white oak (Quercus alba L.), black cherry (Prunus serotina Ehrh.) and white ash (Fraxinus americana L.)) and three evergreen (eastern hemlock (Tsuga canadensis L.), white pine (Pinus strobus L.) and white spruce (Picea glauca (Moench) Voss.)) tree species growing on acidic forest soils; and (2) examine how leaf phenology and other traits that distinguish evergreen and deciduous tree species influence foliar Mn accumulation rates and sensitivity to excess Mn. For the first objective, leaf samples of seedlings from five acidic, non-glaciated field sites on Pennsylvania's Allegheny Plateau were collected and analyzed for leaf element concentrations. In a second study, we examined growth and photosynthetic responses of seedlings exposed to excess Mn in sand culture. In field samples, Mn in deciduous foliage hyperaccumulated to concentrations more than twice as high as those found in evergreen needles. Among species, sugar maple was the most sensitive to excess Mn based on growth and photosynthetic measurements. Photosynthesis in red maple and red oak was also sensitive to excess Mn, whereas white oak, black cherry, white ash and the three evergreen species were tolerant of excess Mn. Among the nine species, relative rates of photosynthesis were negatively correlated with foliar Mn concentrations, suggesting that photosynthetic sensitivity to Mn is a function of its rate of accumulation in seedling foliage.

  11. Protected areas: mixed success in conserving East Africa's evergreen forests.

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    Marion Pfeifer

    Full Text Available In East Africa, human population growth and demands for natural resources cause forest loss contributing to increased carbon emissions and reduced biodiversity. Protected Areas (PAs are intended to conserve habitats and species. Variability in PA effectiveness and 'leakage' (here defined as displacement of deforestation may lead to different trends in forest loss within, and adjacent to, existing PAs. Here, we quantify spatial variation in trends of evergreen forest coverage in East Africa between 2001 and 2009, and test for correlations with forest accessibility and environmental drivers. We investigate PA effectiveness at local, landscape and national scales, comparing rates of deforestation within park boundaries with those detected in park buffer zones and in unprotected land more generally. Background forest loss (BFL was estimated at -9.3% (17,167 km(2, but varied between countries (range: -0.9% to -85.7%; note: no BFL in South Sudan. We document high variability in PA effectiveness within and between PA categories. The most successful PAs were National Parks, although only 26 out of 48 parks increased or maintained their forest area (i.e. Effective parks. Forest Reserves (Ineffective parks, i.e. parks that lose forest from within boundaries: 204 out of 337, Nature Reserves (six out of 12 and Game Parks (24 out of 26 were more likely to lose forest cover. Forest loss in buffer zones around PAs exceeded background forest loss, in some areas indicating leakage driven by Effective National Parks. Human pressure, forest accessibility, protection status, distance to fires and long-term annual rainfall were highly significant drivers of forest loss in East Africa. Some of these factors can be addressed by adjusting park management. However, addressing close links between livelihoods, natural capital and poverty remains a fundamental challenge in East Africa's forest conservation efforts.

  12. Structure and Regeneration Status of Gedo Dry Evergreen Montane ...

    African Journals Online (AJOL)

    This study was conducted on Gedo Dry Evergreen Montane Forest in West Shewa Zone of Oromia National Regional State, 182-196 km west of Addis Ababa (Finfinne). The objective of the study was to determine structure and regeneration status of Gedo Forest. All trees and shrubs with Diameter at Breast Height (DBH) ...

  13. A Student Government Guidebook for Evergreen Valley College.

    Science.gov (United States)

    Chavez, Mauro

    Designed to help develop informed and capable student leadership in student affairs at Evergreen Valley College (EVC), this student government guide and text for Government 91 focuses on the major leadership needs and objectives of student government within a participatory framework. After an explanation of course objectives and requirements,…

  14. An Instructional Guide for Ethnic Studies at Evergreen Valley College.

    Science.gov (United States)

    Chavez, Mauro

    Guidelines and conceptual parameters are presented for ethnic studies courses at Evergreen Valley College (EVC). Introductory material discusses the requirement that all associate degree students complete three units of ethnic studies; presents general guidelines for ethnic studies; defines "ethnic-racial minority"; and suggests criteria for…

  15. Transpiration and water use efficiency in native chilean and exotic species, a usefull tool for catchment management?

    Science.gov (United States)

    Hervé-Fernández, P.; Oyarzun, C. E.

    2012-04-01

    Land-use and forest cover change play important roles in socio-economic processes and have been linked with water supply and other ecosystem services in various regions of the world. Water yield from watersheds is a major ecosystem service for human activities but has been altered by landscape management superimposed on climatic variability and change. Sustaining ecosystem services important to humans, while providing a dependable water supply for agriculture and urban needs is a major challenge faced by managers of human-dominated or increased antropical effect over watersheds. Since water is mostly consumed by vegetation (i.e: transpiration), which strongly depends on trees physiological characteristics (i.e: foliar area, transpiration capacity) are very important. The quantity of water consumed by plantations is influenced mainly by forest characteristics (species physiology, age and management), catchment water retention capacity and meteorological characteristics. Eventhough in Chile, the forest sector accounts for 3.6% of the gross domestic product (GDP) and 12.5% of total exports (INFOR, 2003), afforestation with fast growing exotic species has ended up being socially and politically questionable because of the supposed impact on the environment and water resources. We present data of trees transpiration and water use efficiency from three headwater catchments: (a) second growth native evergreen forest (Aetoxicon punctatum, Drimys winterii, Gevuina avellana, Laureliopsis philippiana); (b) Eucalyptus globulus plantation, and (c) a mixed native deciduous (Nothofagus obliqua and some evergreen species) forest and Eucalyptus globulus and Acacia melanoxylon plantation located at the Coastal Mountain Range in southern Chile (40°S). Annual transpiration rates ranged from 1.24 ± 0.41 mol•m-2•s-1 (0.022 ± 0.009 L•m-2•s-1) for E. globulus, while the lowest observed was for L. philippiana 0.44 ± 0.31 mol•m-2•s-1 (0.008 ± 0.006 L•m-2•s-1). However

  16. Micropropagación in vitro de Nothofagus alpina utilizando fitohormonas

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    Luz García Cruzatty

    2015-09-01

    Full Text Available Nothofagus alpina es una de las especies forestales más importantes del Sur de Chile y Argentina, países donde se ha empezado con programas de mejoramiento genético. La micropropagación es una técnica muy útil en la clonación de árboles con fines de mejoramiento, por tanto, los objetivos planteados en esta investigación fueron: determinar la mejor concentración de fitohormonas 6-bencilaminopurina (BAP y ácido indol butírico (AIB y, el medio de cultivo idóneo para inducir el enraizamiento de brotes y la brotación de secciones nodales de N. alpina. Se evaluaron los medios de Murashige Skoog (MS y Wood Plant Medium (WPM, con la mitad de los macronutrientes (enraizamiento y los micronutrientes completos (multiplicación, suplementado con peptone (0.1%, sacarosa (2.0%, agar (0.7% y diferentes concentraciones de auxinas. El medio MS suplementado con 2 mg L-1 de AIB resultó mejor para inducir la producción de las raíces, tanto en número como en la longitud de la raíz principal. El mayor porcentaje de enraizamiento se registró en el medio WPM suplementado con 2 mg L-1 AIB. Los tratamientos para inducir multiplicación que incluyeron citoquinina originaron callos y no enraizaron; siendo mayor la presencia de callos en el medio WPM. Se sugiere que la aplicación de citoquininas no es indispensable para la brotación, puesto que en los tratamientos testigos hubo una buena brotación; lo que hace suponer que el material vegetal utilizado tiene suficiente niveles endógenos de esta fitohormona.

  17. Size-specific tree mortality varies with neighbourhood crowding and disturbance in a Montane Nothofagus forest.

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    Jennifer M Hurst

    Full Text Available Tree mortality is a fundamental process governing forest dynamics, but understanding tree mortality patterns is challenging because large, long-term datasets are required. Describing size-specific mortality patterns can be especially difficult, due to few trees in larger size classes. We used permanent plot data from Nothofagus solandri var. cliffortioides (mountain beech forest on the eastern slopes of the Southern Alps, New Zealand, where the fates of trees on 250 plots of 0.04 ha were followed, to examine: (1 patterns of size-specific mortality over three consecutive periods spanning 30 years, each characterised by different disturbance, and (2 the strength and direction of neighbourhood crowding effects on size-specific mortality rates. We found that the size-specific mortality function was U-shaped over the 30-year period as well as within two shorter periods characterised by small-scale pinhole beetle and windthrow disturbance. During a third period, characterised by earthquake disturbance, tree mortality was less size dependent. Small trees (<20 cm in diameter were more likely to die, in all three periods, if surrounded by a high basal area of larger neighbours, suggesting that size-asymmetric competition for light was a major cause of mortality. In contrast, large trees (≥ 20 cm in diameter were more likely to die in the first period if they had few neighbours, indicating that positive crowding effects were sometimes important for survival of large trees. Overall our results suggest that temporal variability in size-specific mortality patterns, and positive interactions between large trees, may sometimes need to be incorporated into models of forest dynamics.

  18. Phylogeographical patterns of a generalist acorn weevil: insight into the biogeographical history of broadleaved deciduous and evergreen forests.

    Science.gov (United States)

    Aoki, Kyoko; Kato, Makoto; Murakami, Noriaki

    2009-05-16

    Climatic changes during glacial periods have had a major influence on the recent evolutionary history of living organisms, even in temperate forests on islands, where the land was not covered with ice sheets. We investigated the phylogeographical patterns of the weevil Curculio sikkimensis (Curculionidae), a generalist seed predator of Fagaceae plants living in both deciduous oak and evergreen forests of Japan. Its genetic structure was compared to that of another host-specific seed predator, C. hilgendorfi, inhabiting only evergreen forests. We examined 921 bp of mitochondrial DNA for 115 individuals collected from 33 populations of C. sikkimensis from 11 plant species of three genera, Quercus, Lithocarpus, and Castanopsis. An analysis of molecular variance revealed that a large proportion (almost 50%, P ages, in the southwestern and northeastern parts of the main islands, although these two types of forests are presently distributed in cool and warm temperate zones of Japan, respectively.

  19. Whole-tree distribution and temporal variation of non-structural carbohydrates in broadleaf evergreen trees.

    Science.gov (United States)

    Smith, Merryn G; Miller, Rebecca E; Arndt, Stefan K; Kasel, Sabine; Bennett, Lauren T

    2017-11-03

    Non-structural carbohydrates (NSCs) form a fundamental yet poorly quantified carbon pool in trees. Studies of NSC seasonality in forest trees have seldom measured whole-tree NSC stocks and allocation among organs, and are not representative of all tree functional types. Non-structural carbohydrate research has primarily focussed on broadleaf deciduous and coniferous evergreen trees with distinct growing seasons, while broadleaf evergreen trees remain under-studied despite their different growth phenology. We measured whole-tree NSC allocation and temporal variation in Eucalyptus obliqua L'Hér., a broadleaf evergreen tree species typically occurring in mixed-age temperate forests, which has year-round growth and the capacity to resprout after fire. Our overarching objective was to improve the empirical basis for understanding the functional importance of NSC allocation and stock changes at the tree- and organ-level in this tree functional type. Starch was the principal storage carbohydrate and was primarily stored in the stem and roots of young (14-year-old) trees rather than the lignotuber, which did not appear to be a specialized starch storage organ. Whole-tree NSC stocks were depleted during spring and summer due to significant decreases in starch mass in the roots and stem, seemingly to support root and crown growth but potentially exacerbated by water stress in summer. Seasonality of stem NSCs differed between young and mature trees, and was not synchronized with stem basal area increments in mature trees. Our results suggest that the relative magnitude of seasonal NSC stock changes could vary with tree growth stage, and that the main drivers of NSC fluctuations in broadleaf evergreen trees in temperate biomes could be periodic disturbances such as summer drought and fire, rather than growth phenology. These results have implications for understanding post-fire tree recovery via resprouting, and for incorporating NSC pools into carbon models of mixed

  20. Phylogeographical patterns of a generalist acorn weevil: insight into the biogeographical history of broadleaved deciduous and evergreen forests

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    Kato Makoto

    2009-05-01

    Full Text Available Abstract Background Climatic changes during glacial periods have had a major influence on the recent evolutionary history of living organisms, even in temperate forests on islands, where the land was not covered with ice sheets. We investigated the phylogeographical patterns of the weevil Curculio sikkimensis (Curculionidae, a generalist seed predator of Fagaceae plants living in both deciduous oak and evergreen forests of Japan. Its genetic structure was compared to that of another host-specific seed predator, C. hilgendorfi, inhabiting only evergreen forests. Results We examined 921 bp of mitochondrial DNA for 115 individuals collected from 33 populations of C. sikkimensis from 11 plant species of three genera, Quercus, Lithocarpus, and Castanopsis. An analysis of molecular variance revealed that a large proportion (almost 50%, P Conclusion Our results suggest that geology and historical environment have contributed to shaping the present genetic structure of C. sikkimensis. The geographical patterns of genetic differentiation in the Chugoku-Shikoku region observed in the two types of Fagaceae-associated Curculio in this study have also been observed in several plant species growing in warm and cool temperate zones of Japan. The occurrence of this common pattern suggests that deciduous oak and evergreen forests of Japan survived together, or adjacent to each other, in small refugia during glacial ages, in the southwestern and northeastern parts of the main islands, although these two types of forests are presently distributed in cool and warm temperate zones of Japan, respectively.

  1. Patrones de dispersión de semillas y colonización de Misodendrum punctulatum (Misodendraceae en un matorral postfuego de Nothofagus antarctica (Nothofagaceae del noroeste de la Patagonia Misodendrum punctulatum (Misodendraceae seed dispersal and colonization patterns on a Nothofagus antarctica (Nothofagaceae post-fire shrubland from Northwestern Patagonia

    Directory of Open Access Journals (Sweden)

    NORLAN TERCERO-BUCARDO

    2010-01-01

    allow understand the patterns of spatial distribution and infection dynamics of Misodendrum punctulatum. In order to plan management strategies, understanding the infection dynamics is useful to perform successfully strategies to the control of hemiparasitic plants in forest to commercial use, and conservation or restoration strategies, e.g. to restorate this hemiparasitic specie in areas recently colonized by N. antárctica. These studied aspects in Misodendrum punctulatum contribute to the knowledge of this ecological interaction, which is frequent in Nothofagus forests from Argentina and Chile.

  2. Caída de tefra y su influencia sobre la estructura y dinámica de los bosques andinos de Nothofagus en el Parque Nacional Puyehue, Chile

    Science.gov (United States)

    Mauricio Montiel; Mauro E González; Charles M Crisafulli

    2016-01-01

    Tephra fall influences the structure and dynamics of Andean Nothofagus (beech) forests in Puyehue National Park, Chile. Forest mortality and subsequent establishment, structure and composition have been affected by the eruption of the Puyehue-Cordon Caulle volcano complex.

  3. Observations on arbuscular mycorrhiza associated with important edible tuberous plants grown in wet evergreen forest in Assam, India

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    RAJA RISHI

    2013-10-01

    Full Text Available Kumar R, Tapwal A, Pandey S, Rishi R, Borah D. 2013. Observations on arbuscular mycorrhiza associated with important edible tuberous plants grown in wet evergreen forest in Assam, India. Biodiversitas 14: 67-72. Non-timber forest products constitute an important source of livelihood for rural households from forest fringe communities across the world. Utilization of wild edible tuber plants is an integral component of their culture. Mycorrhizal associations influence the establishment and production of tuber plants under field conditions.The aim of present study is to explore the diversity and arbuscular mycorrhizal (AMF colonization of wild edible tuber plants grown in wet evergreen forest of Assam, India. A survey was conducted in 2009-10 in Sunaikuchi, Khulahat, and Bura Mayong reserved forest of Morigaon district of Assam to determine the AMF spore population in rhizosphere soils and root colonization of 14 tuberous edible plants belonging to five families. The results revealed AMF colonization of all selected species in all seasons. The percent colonization and spore count was less in summer, moderate in winter and highest in rainy season. Seventeen species of arbuscular mycorrhizal fungi were recorded in four genera viz. Acaulospora (7 species, Glomus (5 species, Sclerocystis (3 species and Gigaspora (2 species.

  4. Efecto del ácido indolbutírico, del tipo de la cama de arraigamiento, del substrato, y del árbol madre en la capacidad de arraigamiento de estacas de Nothofagus glauca (Phil. Krasser Effect of indolebutyric acid, bottom heat, substrate, and parent tree on rooting capacity of Nothofagus glauca (Phil. Krasser stem cuttings

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    RÓMULO SANTELICES

    2006-03-01

    Full Text Available Nothofagus glauca (Phil. Krasser es una especie característica de la zona mesomórfica de Chile que tiene problemas de conservación y de la cual existe insuficiente información sobre técnicas de propagación vegetativa; por ello se estudiaron algunos aspectos relacionados con el arraigamiento de estacas. A partir de material cosechado en noviembre de 1995 y de 1997, se evaluó el efecto del ácido indolbutírico (AIB (0; 0,5; 1; 2 %; del tipo de cama de arraigamiento (caliente y fría; del substrato empleado (aserrín y corteza de Pinus radiata D. Don; y del árbol madre. Los ensayos, de 2,5 a 4 meses de duración se realizaron en un invernadero equipado con un sistema de riego automatizado y con cama caliente que mantuvo una temperatura entre 21 y 25 °C en la base de las estacas. Los resultados mostraron que N. glauca puede propagarse por estacas de material juvenil provenientes de rebrotes de tocón, colectadas en el mes de noviembre. La respuesta de arraigamiento aumentó a medida que la concentración de AIB alcanzó hasta 1 % (88 % de estacas enraizadas, para luego disminuir con una concentración de 2 %. La presencia de hojas fue fundamental en la respuesta, ya que estacas sin ellas no indujeron raíces ni sobrevivieron. El empleo de cama caliente no mostró ningún efecto en el proceso de rizogénesis, por lo que no se justifica su uso. Respecto del substrato, solo se observaron diferencias significativas en el número de raíces producidas, siendo más favorable emplear aserrín. Finalmente, se observa una marcada influencia del árbol madre en la formación de raíces adventicias, lo que no solo se manifiesta en la tasa de enraizamiento (de 6,7 a 80 %, sino que también en la cantidad y longitud de las raíces desarrolladasNothofagus glauca (Phil. Krasser is a tree of conservation concern that is characteristic for the mesomorphic zone of Chile. Techniques for vegetative propagation of this species are not well known. In this study

  5. DNA barcode authentication of wood samples of threatened and commercial timber trees within the tropical dry evergreen forest of India.

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    Stalin Nithaniyal

    Full Text Available BACKGROUND: India is rich with biodiversity, which includes a large number of endemic, rare and threatened plant species. Previous studies have used DNA barcoding to inventory species for applications in biodiversity monitoring, conservation impact assessment, monitoring of illegal trading, authentication of traded medicinal plants etc. This is the first tropical dry evergreen forest (TDEF barcode study in the World and the first attempt to assemble a reference barcode library for the trees of India as part of a larger project initiated by this research group. METHODOLOGY/PRINCIPAL FINDINGS: We sampled 429 trees representing 143 tropical dry evergreen forest (TDEF species, which included 16 threatened species. DNA barcoding was completed using rbcL and matK markers. The tiered approach (1st tier rbcL; 2nd tier matK correctly identified 136 out of 143 species (95%. This high level of species resolution was largely due to the fact that the tree species were taxonomically diverse in the TDEF. Ability to resolve taxonomically diverse tree species of TDEF was comparable among the best match method, the phylogenetic method, and the characteristic attribute organization system method. CONCLUSIONS: We demonstrated the utility of the TDEF reference barcode library to authenticate wood samples from timber operations in the TDEF. This pilot research study will enable more comprehensive surveys of the illegal timber trade of threatened species in the TDEF. This TDEF reference barcode library also contains trees that have medicinal properties, which could be used to monitor unsustainable and indiscriminate collection of plants from the wild for their medicinal value.

  6. DNA Barcode Authentication of Wood Samples of Threatened and Commercial Timber Trees within the Tropical Dry Evergreen Forest of India

    Science.gov (United States)

    Nithaniyal, Stalin; Newmaster, Steven G.; Ragupathy, Subramanyam; Krishnamoorthy, Devanathan; Vassou, Sophie Lorraine; Parani, Madasamy

    2014-01-01

    Background India is rich with biodiversity, which includes a large number of endemic, rare and threatened plant species. Previous studies have used DNA barcoding to inventory species for applications in biodiversity monitoring, conservation impact assessment, monitoring of illegal trading, authentication of traded medicinal plants etc. This is the first tropical dry evergreen forest (TDEF) barcode study in the World and the first attempt to assemble a reference barcode library for the trees of India as part of a larger project initiated by this research group. Methodology/Principal Findings We sampled 429 trees representing 143 tropical dry evergreen forest (TDEF) species, which included 16 threatened species. DNA barcoding was completed using rbcL and matK markers. The tiered approach (1st tier rbcL; 2nd tier matK) correctly identified 136 out of 143 species (95%). This high level of species resolution was largely due to the fact that the tree species were taxonomically diverse in the TDEF. Ability to resolve taxonomically diverse tree species of TDEF was comparable among the best match method, the phylogenetic method, and the characteristic attribute organization system method. Conclusions We demonstrated the utility of the TDEF reference barcode library to authenticate wood samples from timber operations in the TDEF. This pilot research study will enable more comprehensive surveys of the illegal timber trade of threatened species in the TDEF. This TDEF reference barcode library also contains trees that have medicinal properties, which could be used to monitor unsustainable and indiscriminate collection of plants from the wild for their medicinal value. PMID:25259794

  7. Responses of the photosynthetic apparatus to winter conditions in broadleaved evergreen trees growing in warm temperate regions of Japan.

    Science.gov (United States)

    Tanaka, Chizuru; Nakano, Takashi; Yamazaki, Jun-Ya; Maruta, Emiko

    2015-01-01

    Photosynthetic characteristics of two broadleaved evergreen trees, Quercus myrsinaefolia and Machilus thunbergii, were compared in autumn and winter. The irradiance was similar in both seasons, but the air temperature was lower in winter. Under the winter conditions, net photosynthesis under natural sunlight (Anet) in both species dropped to 4 μmol CO2 m(-2) s(-1), and the quantum yield of photosystem II (PSII) photochemistry in dark-adapted leaves (Fv/Fm) also dropped to 0.60. In both species the maximum carboxylation rates of Rubisco (V(cmax)) decreased, and the amount of Rubisco increased in winter. A decline in chlorophyll (Chl) concentration and an increase in the Chl a/b ratio in winter resulted in a reduction in the size of the light-harvesting antennae. From measurements of Chl a fluorescence parameters, both the relative fraction and the energy flux rates of thermal dissipation through other non-photochemical processes were markedly elevated in winter. The results indicate that the photosynthetic apparatus in broadleaved evergreen species in warm temperate regions responds to winter through regulatory mechanisms involving the downregulation of light-harvesting and photosynthesis coupled with increased photoprotective thermal energy dissipation to minimize photodamage in winter. These mechanisms aid a quick restart of photosynthesis without the development of new leaves in the following spring. Copyright © 2014 Elsevier Masson SAS. All rights reserved.

  8. Desarrollo foliar y caulinar de las unidades de alargamiento de Nothofagus dombeyi (Nothofagaceae en condiciones de alta y baja luminosidad Leaf and stem development in extension units of Nothofagus dombeyi (Nothofagaceae under high and low light conditions

    Directory of Open Access Journals (Sweden)

    Cecilia Calabria

    2008-07-01

    Full Text Available Se analizaron el tamaño del tallo y las hojas que componen las unidades de alargamiento (UA del tronco, las ramas principales y las ramas cortas de ejemplares juveniles de Nothofagus dombeyi desarrollados en comunidades de áreas abiertas (bordes de camino y de sotobosque de Patagonia. Se evaluaron el área y la forma (ancho/longitud de las hojas a lo largo de las UA, el área foliar específica (AFE y las relaciones área foliar/volumen del tallo, longitud del tallo/peso del tallo y volumen del tallo/peso del tallo. Para igual posición en la UA, las hojas del tronco son mayores que las de las ramas principales y éstas mayores que las de las ramas cortas. En las UA del tronco el desarrollo caulinar es proporcionalmente mayor al de las hojas en comparación con las UA de las ramas principales y, en especial, de las ramas cortas. La restricción en el desarrollo caulinar y el aumento del AFE en ejemplares de N. dombeyi creciendo a la sombra permitiría su supervivencia pero con limitado desarrollo en altura y, en consecuencia, baja probabilidad de alcanzar el dosel.The size of stem and leaves was studied for trunk, main branch and short branch extension units (EU of young Nothofagus dombeyi trees growing in open areas (road verges and understory communities in Patagonia. The surface area and outline (width/length ratio of single leaves along EU, the specific leaf area, and the ratios leaf area/stem volume, stem length/stem mass and stem volume/stem mass were assessed. Trunk leaves were larger than main-branch leaves and main-branch leaves larger than short-branch leaves in similar positions on the EU. Stem developed proportionally more than leaves in trunk EU than in main-branch EU and, especially, short-branch EUs. Restrictions in stem development and increases in specific leaf area would allow N. dombeyi trees to survive under shaded conditions though limiting their height growth and, consequently, their chances to reach the canopy.

  9. Facilitating the recovery of natural evergreen forests in South Africa via invader plant stands

    Directory of Open Access Journals (Sweden)

    Coert J. Geldenhuys

    2017-11-01

    Full Text Available Contrary to general belief, planted and naturalized stands of introduced species facilitate the recovery of natural evergreen forests and their diversity. Forest rehabilitation actions are often performed at great cost: mature forest species are planted, while species with adaptations to recover effectively and quickly after severe disturbance are ignored; or stands are cleared of invasive alien species before native tree species are planted. By contrast, cost-effective commercial plantation forestry systems generally use fast-growing pioneer tree species introduced from other natural forest regions. Such planted tree stands often facilitate the recovery of shade-tolerant native forest species. This paper provides a brief overview of disturbance-recovery processes at landscape level, and how pioneer stands of both native and introduced tree species develop from monocultures to diverse mature forest communities. It uses one example of a study of how natural forest species from small forest patches of 3 ha in total invaded a 90-ha stand of the invasive Black wattle, Acacia mearnsii, over a distance of 3.1 ha at Swellendam near Cape Town, South Africa. The study recorded 329 forest species clusters across the wattle stand: more large clusters closer to and more smaller clusters further away from natural forest patches. The 28 recorded forest species (of potentially 40 species in the surrounding forest patches included 79% tree and 21% shrub species. Colonizing forest species had mostly larger fleshy fruit and softer small seeds, and were dispersed by mostly birds and primate species. Maturing forest trees within developing clusters in the wattle stand became a source for forest regeneration away from the clusters, showing different expansion patterns. Four sets of fenced-unfenced plots in the wattle stand showed the impact of browsing by livestock, antelope, rodents and insects on the successful establishment of regenerating forest species, and the

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

    Science.gov (United States)

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

    2013-06-01

    We investigated the effects of major environmental drivers associated with urbanization on species diversity and plant functional traits (PFTs) in the remnant subtropical evergreen broad-leaved forests in Metropolitan Guangzhou (Guangdong, China). Twenty environmental factors including topography, light, and soil properties were used to quantify the effects of urbanization. Vegetation data and soil properties were collected from 30 400-m(2) plots at 6 study sites in urban and rural areas. The difference of plant species diversity and PFTs of remnant forests between urban and rural areas were analyzed. To discern the complex relationships, multivariate statistical analyses (e.g., canonical correspondence analysis and regression analysis) were employed. Pioneer species and stress-tolerant species can survive and vigorously establish their population dominance in the urban environment. The native herb diversity was lower in urban forests than in rural forests. Urban forests tend to prefer the species with Mesophanerophyte life form. In contrast, species in rural forests possessed Chamaephyte and Nanophanerophyte life forms and gravity/clonal growth dispersal mode. Soil pH and soil nutrients (K, Na, and TN) were positively related to herb diversity, while soil heavy metal concentrations (Cu) were negatively correlated with herb diversity. The herb plant species diversity declines and the species in the remnant forests usually have stress-tolerant functional traits in response to urbanization. The factors related to urbanization such as soil acidification, nutrient leaching, and heavy metal pollution were important in controlling the plant diversity in the forests along the urban-rural gradients. Urbanization affects the structure and functional traits of remnant subtropical evergreen broad-leaved forests.

  11. New species of Tomentella (Thelephorales) from the Patagonian Andes forests.

    Science.gov (United States)

    Kuhar, Francisco; Barroetaveña, Carolina; Rajchenberg, Mario

    2016-01-01

    The genus Tomentella forms abundant ectomycorrhizae in coniferous and deciduous forests worldwide. Molecular identification of root tips suggests undescribed species in the Nothofagus forests of Patagonia, Argentina. Tomentella tenuissima, T. pulvinulata and T. patagonica are described here as new to science based on morphological and molecular analyses. Their host range is addressed using available soil sequences. The identity of previous records of T. galzinii and T. radiosa are discussed with morphological and molecular evidence. © 2016 by The Mycological Society of America.

  12. The southernmost Andean Mountain soils: a toposequence from Nothofagus Forest to Sub Antarctic Tundra at Ushuaia, Tierra del Fuego

    Science.gov (United States)

    Firme Sá, Mariana M.; Schaefer, Carlos E.; Loureiro, Diego C.; Simas, Felipe N.; Francelino, Marcio R.; Senra, Eduardo O.

    2015-04-01

    Located at the southern tip of the Fuegian Andes Cordilhera, the Martial glacier witnessed a rapid process of retreat in the last century. Up to now little is known about the development and genesis of soils of this region. A toposequence of six soils, ranging from 430-925 m a.s.l, was investigated, with emphasis on genesis, chemical and mineralogical properties. The highest, youngest soil is located just below the Martial Glacier Martial Sur sector, and the lowest soils occur on sloping moraines under Nothofagus pumilio forests. Based on chemical, physical and mineralogical characteristics, the soils were classified according to the Soil taxonomy, being keyed out as Inceptisols and Entisols. Soil parent material of the soil is basically moraines, in which the predominant lithic components dominated by metamorphic rocks, with allochthonous contributions of wind-blown materials (very small fragments of volcanic glass) observed by hand lens in all horizons, except the highest profile under Tundra. In Nothofagus Deciduous Forests at the lowest part of the toposequence, poorly developed Inceptisols occur with Folistic horizons, with mixed "andic" and "spodic" characters, but with a predominance of andosolization (Andic Drystrocryepts). Under Tundra vegetation, Inceptisols are formed under hydromorphism and andosolization processes (Oxiaquic Dystrocrepts and Typic Dystrocrepts). On highland periglacial environments, soils without B horizon with strong evidence of cryoturbation and cryogenesis occur, without present-day permafrost down to 2 meters (Typic Cryorthents and Lithic Haploturbels). The mountain soils of Martial glacier generalize young, stony and rich in organic matter, with the exception of barely vegetated Tundra soils at higher altitudes. The forest soils are more acidic and have higher Al3+activity. All soils are dystrophic, except for the highest profile of the local periglacial environment. The organic carbon amounts are higher in forest soils and

  13. Evergreening by whom? A review of secondary patents for omeprazole.

    Science.gov (United States)

    Lloyd, Mike

    2013-11-01

    Evergreening, or the practice of technology developers to retain legal protection over valuable drugs beyond the normal patent term, is a well known practice by originators of successful drugs. Generic competitors also attempt similar strategies for commercial reasons. In this paper we look at secondary US and European patents in relation to the 'blockbuster' drug omeprazole (e.g., Prilosec® by AstraZeneca among other brands), with these secondary patents selected because they refer to the 'omeprazole' in either the title, abstract, Derwent Title or first claim. We find that 485 patents meet this criteria, with only 29% owned by the drugs originator (or known subsidiaries or predecessors). AstraZeneca was also the leading applicant by a number of measures, including grant ratio, number of patents filed, forward citation count, family member count and claim breadth.

  14. Solar Physics at Evergreen: Solar Dynamo and Chromospheric MHD

    Science.gov (United States)

    Zita, E. J.; Maxwell, J.; Song, N.; Dikpati, M.

    2006-12-01

    We describe our five year old solar physics research program at The Evergreen State College. Famed for its cloudy skies, the Pacific Northwest is an ideal location for theoretical and remote solar physics research activities. Why does the Sun's magnetic field flip polarity every 11 years or so? How does this contribute to the magnetic storms Earth experiences when the Sun's field reverses? Why is the temperature in the Sun's upper atmosphere millions of degrees higher than the Sun's surface temperature? How do magnetic waves transport energy in the Sun’s chromosphere and the Earth’s atmosphere? How does solar variability affect climate change? Faculty and undergraduates investigate questions such as these in collaboration with the High Altitude Observatory (HAO) at the National Center for Atmospheric Research (NCAR) in Boulder. We will describe successful student research projects, logistics of remote computing, and our current physics investigations into (1) the solar dynamo and (2) chromospheric magnetohydrodynamics.

  15. Fragmentation patterns of evergreen oak woodlands in Southwestern Iberia

    DEFF Research Database (Denmark)

    Costa, A.; Madeira, M.; Lima Santos, J.

    2014-01-01

    Mediterranean evergreen oak woodlands (composed of Quercus suber L. and Quercus rotundifolia Lam.) are becoming increasingly fragmented in the human-modified landscapes of Southwestern Portugal and Spain. Previous studies have largely neglected to assess the spatial changes of oak woodlands...... in relation to their surrounding landscape matrix, and to characterize and quantify woodland boundaries and edges. The present study aims to fill this gap by analyzing fragmentation patterns of oak woodlands over a 50-year period (1958-2007) in three landscapes. Using archived aerial imagery from 1958, 1995...... and 2007, for two consecutive periods (1958-1995 and 1995-2007), we calculated a set of landscape metrics to compare woodland fragmentation over time. Our results indicated a continuous woodland fragmentation characterized by their edge dynamics. From 1958 to 2007, the replacement of open farmland...

  16. Decaying Wood Preference of Stag Beetles (Coleoptera: Lucanidae) in a Tropical Dry-Evergreen Forest.

    Science.gov (United States)

    Songvorawit, Nut; Butcher, Buntika Areekul; Chaisuekul, Chatchawan

    2017-12-08

    Larvae of many insect species, including stag beetles, have a limited mobility from their initial oviposition site. The fate of immature stages, therefore, depends on the maternal choice of oviposition site. Decaying wood preference by stag beetles was studied in a dry-evergreen forest in Chanthaburi province, Thailand. From a total of 270 examined logs, 52 contained stag beetles (255 total), which were identified to eight species from five genera. Aegus chelifer chelifer MacLeay, 1819 (Coleoptera: Lucanidae) was the dominant species both by occurrence and by number of individuals. The occurrence and numbers of stag beetle larvae found in logs was more frequent in those of a moderate decay class, which had moderate hardness and water content. Principal component analysis (PCA) revealed that logs with stag beetles had relatively high nitrogen content and fungal biomass. Thus, selection of oviposition sites by stag beetles was likely to depend on both the log decay stage (or hardness) to protect immature stages from natural enemies and its nutritional properties to enhance the larval performance. © The Authors 2017. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  17. Allometric Equations for Aboveground and Belowground Biomass Estimations in an Evergreen Forest in Vietnam.

    Directory of Open Access Journals (Sweden)

    Vu Thanh Nam

    Full Text Available Allometric regression models are widely used to estimate tropical forest biomass, but balancing model accuracy with efficiency of implementation remains a major challenge. In addition, while numerous models exist for aboveground mass, very few exist for roots. We developed allometric equations for aboveground biomass (AGB and root biomass (RB based on 300 (of 45 species and 40 (of 25 species sample trees respectively, in an evergreen forest in Vietnam. The biomass estimations from these local models were compared to regional and pan-tropical models. For AGB we also compared local models that distinguish functional types to an aggregated model, to assess the degree of specificity needed in local models. Besides diameter at breast height (DBH and tree height (H, wood density (WD was found to be an important parameter in AGB models. Existing pan-tropical models resulted in up to 27% higher estimates of AGB, and overestimated RB by nearly 150%, indicating the greater accuracy of local models at the plot level. Our functional group aggregated local model which combined data for all species, was as accurate in estimating AGB as functional type specific models, indicating that a local aggregated model is the best choice for predicting plot level AGB in tropical forests. Finally our study presents the first allometric biomass models for aboveground and root biomass in forests in Vietnam.

  18. Allometric Equations for Aboveground and Belowground Biomass Estimations in an Evergreen Forest in Vietnam.

    Science.gov (United States)

    Nam, Vu Thanh; van Kuijk, Marijke; Anten, Niels P R

    2016-01-01

    Allometric regression models are widely used to estimate tropical forest biomass, but balancing model accuracy with efficiency of implementation remains a major challenge. In addition, while numerous models exist for aboveground mass, very few exist for roots. We developed allometric equations for aboveground biomass (AGB) and root biomass (RB) based on 300 (of 45 species) and 40 (of 25 species) sample trees respectively, in an evergreen forest in Vietnam. The biomass estimations from these local models were compared to regional and pan-tropical models. For AGB we also compared local models that distinguish functional types to an aggregated model, to assess the degree of specificity needed in local models. Besides diameter at breast height (DBH) and tree height (H), wood density (WD) was found to be an important parameter in AGB models. Existing pan-tropical models resulted in up to 27% higher estimates of AGB, and overestimated RB by nearly 150%, indicating the greater accuracy of local models at the plot level. Our functional group aggregated local model which combined data for all species, was as accurate in estimating AGB as functional type specific models, indicating that a local aggregated model is the best choice for predicting plot level AGB in tropical forests. Finally our study presents the first allometric biomass models for aboveground and root biomass in forests in Vietnam.

  19. Growth reduction after defoliation is independent of CO2 supply in deciduous and evergreen young oaks.

    Science.gov (United States)

    Schmid, Sandra; Palacio, Sara; Hoch, Günter

    2017-06-01

    Reduced productivity of trees after defoliation might be caused by limited carbon (C) availability. We investigated the combined effect of different atmospheric CO2 concentrations (160, 280 and 560 ppm) and early season defoliation on the growth and C reserves (nonstructural carbohydrates (NSC)) of saplings of two oak species with different leaf habits (deciduous Quercus petraea and evergreen Quercus ilex). In both species, higher CO2 supply significantly enhanced growth. Defoliation had a strong negative impact on growth (stronger for Q. ilex), but the relative reduction of growth caused by defoliation within each CO2 treatment was very similar across all three CO2 concentrations. Low CO2 and defoliation led to decreased NSC tissue concentrations mainly in the middle of the growing season in Q. ilex, but not in Q. petraea. However, also in Q. ilex, NSC increased in woody tissues in defoliated and low-CO2 saplings towards the end of the growing season. Although the saplings were C limited under these specific experimental conditions, growth reduction after defoliation was not directly caused by C limitation. Rather, growth of trees followed a strong allometric relationship between total leaf area and conductive woody tissue, which did not change across species, CO2 concentrations and defoliation treatments. © 2017 The Authors. New Phytologist © 2017 New Phytologist Trust.

  20. Phylogeny and biogeography of East Asian evergreen oaks (Quercus section Cyclobalanopsis; Fagaceae): Insights into the Cenozoic history of evergreen broad-leaved forests in subtropical Asia.

    Science.gov (United States)

    Deng, Min; Jiang, Xiao-Long; Hipp, Andrew L; Manos, Paul S; Hahn, Marlene

    2018-02-01

    The evolutionary history of Quercus section Cyclobalanopsis, a dominant lineage in East Asian evergreen broadleaved forests (EBLFs), has not been comprehensively studied using molecular tools. In this study, we reconstruct the first comprehensive phylogeny of this lineage using a genomic approach (restriction-site associated DNA sequencing, RAD-seq), sampling 35 of the ca. 90 species currently recognized, representing all main morphological groups of section Cyclobalanopsis. In addition, 10 other species of Quercus and two outgroups were also sampled. Divergence times were estimated using a relaxed clock model and two fossil calibrations. Ancestral areas and dispersal routes were inferred using statistical dispersal-vicariance analysis and the dispersal-extinction-cladogenesis (DEC) model. The phylogeny of Quercus section Cyclobalanopsis demonstrates the section to be monophyletic, comprising two main lineages and six subclades that are well supported by anatomical traits. Biogeographical reconstructions indicate that the wide northern hemisphere distribution of Quercus was disrupted in the Late Eocene, leading to the main extant groups at about 33 Ma. The earliest divergences in section Cyclobalanopsis correspond to the phased uplift of the Himalayas and lateral extrusion of Indochina at the transition of the Oligocene and Miocene, where the highest rate of diversification occurred in the late Miocene. Dispersal from Sino-Himalaya and the Palaeotropics to Sino-Japan in the Miocene was facilitated by the increased intensity of East Asian summer monsoons and by the Middle Miocene Climatic Optimum. Our results highlight the importance of climatic changes and Indo-Eurasian collision-induced tectonic activities from the Neogene onward to the spatial-temporal diversification patterns of Asian EBLF lineages. Copyright © 2017. Published by Elsevier Inc.

  1. Five new species of the armored scale genus Andaspis MacGillivray (Hemiptera, Coccomorpha, Diaspididae from New Caledonia

    Directory of Open Access Journals (Sweden)

    Fredericka B. Hamilton

    2017-08-01

    Full Text Available New Caledonia is home to many endemic species of plants and animals. Here, we improve our grasp on that biota by describing five new species of armored scale insects in the genus Andaspis: Andaspis brevicornuta sp. n, A. conica sp. n., A. nothofagi sp. n., A. novaecaledoniae sp. n., and A. ornata sp. n. Each is known exclusively from collections on southern beeches (Nothofagus spp. in New Caledonia. A key to the species of Andaspis of New Caledonia is provided.

  2. A cold-tolerant evergreen interspecific hybrid of Ocimum kilimandscharicum and Ocimum basilicum: analyzing trichomes and molecular variations.

    Science.gov (United States)

    Dhawan, Sunita Singh; Shukla, Preeti; Gupta, Pankhuri; Lal, R K

    2016-05-01

    and cold. The analysis showed that O. kilimandscharicum and the hybrid were very close to each other but O. basilicum was more distinct in all respects. The overexpression of the WRKY coding gene showed high expression in the hybrid as compared to O. kilimandscharicum and O. basilicum and the transcription factor microspore-specific (MPS) promoter has also shown overexpression in the hybrid for its response against cold stress. The developed evergreen interspecific hybrid may thus provide a base to various industries which are dependent upon the bioactive constituents of Ocimum species.

  3. Water uptake of Alaskan tundra evergreens during the winter–spring transition

    National Research Council Canada - National Science Library

    Moser, Jonathan G; Oberbauer, Steven F; Sternberg, Leonel da S. L; Ellsworth, Patrick Z; Starr, Gregory; Mortazavi, Behzad; Olivas, Paulo C

    2016-01-01

    .... However, liquid water available for plant uptake may be limited at this time. The study objective was to determine whether evergreen plants are actively taking up water while under snow and/or immediately following snowmelt during spring thaw...

  4. Decoupled leaf and root carbon economics is a key component in the ecological diversity and evolutionary divergence of deciduous and evergreen lineages of genus Rhododendron.

    Science.gov (United States)

    Medeiros, Juliana S; Burns, Jean H; Nicholson, Jaynell; Rogers, Louisa; Valverde-Barrantes, Oscar

    2017-06-01

    We explored trait-trait and trait-climate relationships for 27 Rhododendron species while accounting for phylogenetic relationships and within-species variation to investigate whether leaf and root traits are coordinated across environments and over evolutionary time, as part of a whole-plant economics spectrum. We examined specific leaf area (SLA) and four root traits: specific root length (SRL), specific root tip abundance (SRTA), first order diameter, and link average length, for plants growing in a cold, seasonal climate (Kirtland, Ohio) and a warmer, less seasonal climate (Federal Way, Washington) in the United States. We estimated a phylogeny and species' climate of origin, determined phylogenetic signal on mean traits and within-species variation, and used phylogenetically informed analysis to compare trait-trait and trait-climate relationships for deciduous and evergreen lineages. Mean SLA and within-species variation in SRL were more similar between close relatives than expected by chance. SLA and root traits differed according to climate of origin and across growth environments, though SLA differed within- and among-species less than roots. A negative SRL-SRTA correlation indicates investment in foraging scale vs. precision as a fundamental trade-off defining the root economic spectrum. Also, the deciduous clade exhibited a strong negative relationship between SLA and SRL, while evergreen clades showed a weaker positive or no relationship. Our work suggests that natural selection has shaped relationships between above- and belowground traits in genus Rhododendron and that leaf and root traits may evolve independently. Morphological decoupling may help explain habitat diversity among Rhododendron species, as well as the changes accompanying the divergence of deciduous and evergreen lineages. © 2017 Botanical Society of America.

  5. Terrestrial Macrofungal Diversity from the Tropical Dry Evergreen Biome of Southern India and Its Potential Role in Aerobiology.

    Science.gov (United States)

    Priyamvada, Hema; Akila, M; Singh, Raj Kamal; Ravikrishna, R; Verma, R S; Philip, Ligy; Marathe, R R; Sahu, L K; Sudheer, K P; Gunthe, S S

    2017-01-01

    Macrofungi have long been investigated for various scientific purposes including their food and medicinal characteristics. Their role in aerobiology as a fraction of the primary biological aerosol particles (PBAPs), however, has been poorly studied. In this study, we present a source of macrofungi with two different but interdependent objectives: (i) to characterize the macrofungi from a tropical dry evergreen biome in southern India using advanced molecular techniques to enrich the database from this region, and (ii) to assess whether identified species of macrofungi are a potential source of atmospheric PBAPs. From the DNA analysis, we report the diversity of the terrestrial macrofungi from a tropical dry evergreen biome robustly supported by the statistical analyses for diversity conclusions. A total of 113 macrofungal species belonging to 54 genera and 23 families were recorded, with Basidiomycota and Ascomycota constituting 96% and 4% of the species, respectively. The highest species richness was found in the family Agaricaceae (25.3%) followed by Polyporaceae (15.3%) and Marasmiaceae (10.8%). The difference in the distribution of commonly observed macrofungal families over this location was compared with other locations in India (Karnataka, Kerala, Maharashtra, and West Bengal) using two statistical tests. The distributions of the terrestrial macrofungi were distinctly different in each ecosystem. We further attempted to demonstrate the potential role of terrestrial macrofungi as a source of PBAPs in ambient air. In our opinion, the findings from this ecosystem of India will enhance our understanding of the distribution, diversity, ecology, and biological prospects of terrestrial macrofungi as well as their potential to contribute to airborne fungal aerosols.

  6. Effectiveness of fencing and hunting to control Lama guanicoe browsing damage: Implications for Nothofagus pumilio regeneration in harvested forests.

    Science.gov (United States)

    Martínez Pastur, Guillermo; Soler, Rosina; Ivancich, Horacio; Lencinas, María V; Bahamonde, Héctor; Peri, Pablo L

    2016-03-01

    Browsing damage by native ungulates is often to be considered one of the reasons of regeneration failure in Nothofagus pumilio silvicultural systems. Fencing and hunting in forests at regeneration phase have been proposed to mitigate browsing effects. This study aims to determine effectiveness of these control methods in harvested forests, evaluating browsing damage over regeneration, as well as climate-related constraints (freezing or desiccation). Forest structure and regeneration plots were established in two exclosures against native ungulates (Lama guanicoe) by wire fences in the Chilean portion of Tierra del Fuego island, where tree regeneration density, growth, abiotic damage and quality (multi-stems and base/stem deformation) were assessed. Exclosures did not influence regeneration density (at the initial stage with 1.3 m high). However, sapling height at 10-years old was significantly lower outside (40-50 cm high) than inside exclosures (80-100 cm), and also increased their annual height growth, probably as a hunting effect. Likewise, quality was better inside exclosures. Alongside browsing, abiotic conditions negatively influenced sapling quality in the regeneration phase (20%-28% of all seedlings), but greatly to taller plants (as those from inside exclosure). This highlights the importance of considering climatic factors when analysing browsing effects. For best results, control of guanaco in recently harvested areas by fencing should be applied in combination with a reduction of guanaco density through continuous hunting. The benefits of mitigation actions (fencing and hunting) on regeneration growth may shorten the regeneration phase period in shelterwood cutting forests (30-50% less time), but incremental costs must be analysed in the framework of management planning by means of long-term studies. Copyright © 2015 Elsevier Ltd. All rights reserved.

  7. Ectomycorrhizal fungi enhance nitrogen and phosphorus nutrition of Nothofagus dombeyi under drought conditions by regulating assimilative enzyme activities.

    Science.gov (United States)

    Alvarez, Maricel; Huygens, Dries; Olivares, Erick; Saavedra, Isabel; Alberdi, Miren; Valenzuela, Eduardo

    2009-08-01

    Drought stress conditions (DC) reduce plant growth and nutrition, restraining the sustainable reestablishment of Nothofagus dombeyi in temperate south Chilean forest ecosystems. Ectomycorrhizal symbioses have been documented to enhance plant nitrogen (N) and phosphorus (P) uptake under drought, but the regulation of involved assimilative enzymes remains unclear. We studied 1-year-old N. dombeyi (Mirb.) Oerst. plants in association with the ectomycorrhizal fungi Pisolithus tinctorius (Pers.) Coker & Couch. and Descolea antartica Sing. In greenhouse experiments, shoot and root dry weights, mycorrhizal colonization, foliar N and P concentrations, and root enzyme activities [glutamate synthase (glutamine oxoglutarate aminotransferase (GOGAT), EC 1.4.1.13-14), glutamine synthetase (GS, EC 6.3.1.2), glutamate dehydrogenase (GDH, EC 1.4.1.2-4), nitrate reductase (NR, EC 1.6.6.1), and acid phosphomonoesterase (PME, EC 3.1.3.1-2)] were determined as a function of soil-water content. Inoculation of N. dombeyi with P. tinctorius and D. antartica significantly stimulated plant growth and increased plant foliar N and P concentrations, especially under DC. Ectomycorrhizal inoculation increased the activity of all studied enzymes relative to non-mycorrhizal plants under drought. We speculate that GDH is a key enzyme involved in the enhancement of ectomycorrhizal carbon (C) availability by fuelling the tricarboxylic acid (TCA) cycle under conditions of drought-induced carbon deficit. All studied assimilative enzymes of the ectomycorrhizal associations, involved in C, N, and P transfers, are closely interlinked and interdependent. The up-regulation of assimilative enzyme activities by ectomycorrhizal fungal root colonizers acts as a functional mechanism to increase seedling endurance to drought. We insist upon incorporating ectomycorrhizal inoculation in existing Chilean afforestation programs.

  8. [Biogeographic regionalization of the mammals of tropical evergreen forests in Mesoamerica].

    Science.gov (United States)

    Olguin-Monroy, Hector C; Gutiérrez-Blando, Cirene; Rios-Muñoz, César A; León-Paniagua, Livia; Navarro-Sigüenza, Adolfo G

    2013-06-01

    Mesoamerica is a biologically complex zone that expands from Southern Mexico to extreme Northern Colombia. The biogeographical patterns and relationships of the mammalian fauna associated to the Mesoamerican Tropical Evergreen Forest (MTEF) are poorly understood, in spite of the wide distribution of this kind of habitat in the region. We compiled a complete georeferenced database of mammalian species distributed in the MTEF of specimens from museum collections and scientific literature. This database was used to create potential distribution maps through the use of environmental niche models (ENMs) by using the Genetic Algorithm for Rule-Set Production (GARP) using 22 climatic and topographic layers. Each map was used as a representation of the geographic distribution of the species and all available maps were summed to obtain general patterns of species richness in the region. Also, the maps were used to construct a presence-absence matrix in a grid of squares of 0.5 degrees of side, that was analyzed in a Parsimony Analysis of Endemicity (PAE), which resulted in a hypothesis of the biogeographic scheme in the region. We compiled a total of 41 527 records of 233 species of mammals associated to the MTEF. The maximum concentration of species richness (104-138 species) is located in the areas around the Isthmus of Tehuantepec, Northeastern Chiapas-Western Guatemala, Western Honduras, Central Nicaragua to Northwestern Costa Rica and Western Panama. The proposed regionalization indicates that mammalian faunas associated to these forests are composed of two main groups that are divided by the Isthmus of Tehuantepec in Oaxaca in: a) a Northern group that includes Sierra Madre of Chiapas-Guatemala and Yucatan Peninsula; and b) an austral group, that contains the Pacific slope of Chiapas towards the South including Central America. Some individual phylogenetic studies of mammal species in the region support the relationships between the areas of endemism proposed, which

  9. CHARACTERIZATION OF PHYTOPATHOGENIC FUNGI ASSOCIATED WITH AVOCADOS, STONE FRUITS AND NOTHOFAGUS MACROCARPA

    OpenAIRE

    VALENCIA DIAZ; ANA LUISA

    2011-01-01

    Introduction In Chile three geographic zones can be distinguished from north to south. The north zone has a desert climate and extremely low rainfall, the central zone has dry summers and cold-rainy winters, characteristic of Mediterranean climate, and south zone with low temperatures and high pluviometry. This climatic variation has allowed the development of agriculture with a great diversity of species and cultivates. Chile has natural phytosanitary barriers with, the Pac...

  10. Tree-ring stable isotopes reveal twentieth-century increases in water-use efficiency of Fagus sylvatica and Nothofagus spp. in Italian and Chilean mountains.

    Science.gov (United States)

    Tognetti, Roberto; Lombardi, Fabio; Lasserre, Bruno; Cherubini, Paolo; Marchetti, Marco

    2014-01-01

    Changes in intrinsic water use efficiency (iWUE) were investigated in Fagus sylvatica and Nothofagus spp. over the last century. We combined dendrochronological methods with dual-isotope analysis to investigate whether atmospheric changes enhanced iWUE of Fagus and Nothofagus and tree growth (basal area increment, BAI) along latitudinal gradients in Italy and Chile. Post-maturation phases of the trees presented different patterns in δ13C, Δ13C, δ18O, Ci (internal CO2 concentration), iWUE, and BAI. A continuous enhancement in isotope-derived iWUE was observed throughout the twentieth century, which was common to all sites and related to changes in Ca (ambient CO2 concentration) and secondarily to increases in temperature. In contrast to other studies, we observed a general increasing trend of BAI, with the exception of F. sylvatica in Aspromonte. Both iWUE and BAI were uncoupled with the estimated drought index, which is in agreement with the absence of enduring decline in tree growth. In general, δ13C and δ18O showed a weak relationship, suggesting the major influence of photosynthetic rate on Ci and δ13C, and the minor contribution of the regulation of stomatal conductance to iWUE. The substantial warming observed during the twentieth century did not result in a clear pattern of increased drought stress along these latitudinal transects, because of the variability in temporal trends of precipitation and in specific responses of populations.

  11. Tree-ring stable isotopes reveal twentieth-century increases in water-use efficiency of Fagus sylvatica and Nothofagus spp. in Italian and Chilean mountains.

    Directory of Open Access Journals (Sweden)

    Roberto Tognetti

    Full Text Available Changes in intrinsic water use efficiency (iWUE were investigated in Fagus sylvatica and Nothofagus spp. over the last century. We combined dendrochronological methods with dual-isotope analysis to investigate whether atmospheric changes enhanced iWUE of Fagus and Nothofagus and tree growth (basal area increment, BAI along latitudinal gradients in Italy and Chile. Post-maturation phases of the trees presented different patterns in δ13C, Δ13C, δ18O, Ci (internal CO2 concentration, iWUE, and BAI. A continuous enhancement in isotope-derived iWUE was observed throughout the twentieth century, which was common to all sites and related to changes in Ca (ambient CO2 concentration and secondarily to increases in temperature. In contrast to other studies, we observed a general increasing trend of BAI, with the exception of F. sylvatica in Aspromonte. Both iWUE and BAI were uncoupled with the estimated drought index, which is in agreement with the absence of enduring decline in tree growth. In general, δ13C and δ18O showed a weak relationship, suggesting the major influence of photosynthetic rate on Ci and δ13C, and the minor contribution of the regulation of stomatal conductance to iWUE. The substantial warming observed during the twentieth century did not result in a clear pattern of increased drought stress along these latitudinal transects, because of the variability in temporal trends of precipitation and in specific responses of populations.

  12. The rhizospheric microbial community structure and diversity of deciduous and evergreen forests in Taihu Lake area, China

    National Research Council Canada - National Science Library

    Zhiwen Wei; Xiaolong Hu; Xunhang Li; Yanzhou Zhang; Leichun Jiang; Jing Li; Zhengbing Guan; Yujie Cai; Xiangru Liao

    2017-01-01

    .... However, how the soil and vegetation factors affect the diversity and community composition of bacteria is poorly understood, especially for bacteria associated with evergreen and deciduous trees...

  13. Monitoring Spring Recovery of Photosynthesis and Spectral Reflectance in Temperate Evergreen and Mixed Deciduous Forests

    Science.gov (United States)

    Wong, C. Y.; Arain, M. A.; Ensminger, I.

    2015-12-01

    Evergreen conifers in boreal and temperate regions undergo strong seasonal changes in photoperiod and temperatures, which characterizes their photosynthetic activity with high activity in the growing season and downregulation during the winter season. Monitoring the timing of the transitions in evergreens is difficult since it's a largely invisible process, unlike deciduous trees that have a visible budding and senescence sequence. Spectral reflectance and the photochemical reflectance index (PRI), often used as a proxy for photosynthetic light-use efficiency, provides a promising tool to track the transition of evergreens between inactive and active photosynthetic states. To better understand the relationship between PRI and photosynthetic activity and to contrast this relationship between plant functional types, the spring recovery of an evergreen forest and mixed deciduous forest was monitored using spectral reflectance, chlorophyll fluorescence and gas exchange. All metrics indicate photosynthetic recovery during the spring season. These findings indicate that PRI can be used to observe the spring recovery of photosynthesis in evergreen conifers but may not be best suited for deciduous trees. These findings have implications for remote sensing, which provides a promising long-term monitoring system of whole ecosystems, which is important since their roles in the carbon cycle may shift in response to climate change.

  14. Effect of wildfire on soil physical and chemical properties in a Nothofagus glauca forest, Chile Efecto del fuego en las propiedades físicas y químicas en un bosque de Nothofagus glauca en Chile

    Directory of Open Access Journals (Sweden)

    CREIGHTON M. LITTON

    2003-12-01

    Full Text Available Effects of a wildfire on soil chemical and physical properties in a Nothofagus glauca (Phil. Krasser forest in the Coastal Mountain Range of south-central Chile were investigated. Response of the soil during the first two years following a wildfire was examined, where data from soil in a burned forest were compared to that in an adjacent, unburned stand. The effects that wildfire have on soil properties in this highly fragmented ecosystem are not well understood, but results from this study suggest similar responses to those found in other mediterranean forest systems. Both physical (bulk density, percent soil moisture, and soil organic matter content and chemical properties (exchangeable inorganic nitrogen, extractable phosphorus, exchangeable potassium, and soil pH were examined, and data presented here suggest that soil properties vary in their initial response to fire in this ecosystem. Soil organic matter content and soil moisture decreased following fire and remained lower than values from unburned plots for the duration of the study. Exchangeable potassium increased initially after burning, but values in burned plots decreased with time and by the end of two years were significantly lower than in unburned soil. In turn, extractable phosphorus and soil pH both increased immediately following wildfire and values in burned plots remained significantly higher than unburned plots for the entire measurement period. Exchangeable inorganic nitrogen reached higher levels in soil of burned plots for the autumn measurements (April 1997 and 1998 and lower values in burned plots for the spring measurements (November 1997 and 1998. Soil bulk density remained unchanged following fire. In general, changes in soil properties following fire were greatest at the 0-5 cm layer and more modest at the 5-10 cm sampling depth. These changes were related primarily to oxidation of the detrital layer during fire and concurrent changes in the soil environment

  15. Influencia de las especies del dosel en la disponibilidad de recursos y regeneración avanzada en un bosque templado lluvioso del sur de Chile Influence of overstorey species identity on resource availability and variation in composition of advanced regeneration in a temperate rainforest in southern Chile

    Directory of Open Access Journals (Sweden)

    ALFREDO SALDAÑA

    2003-12-01

    advanced regeneration was studied in a temperate rain forest in southern Chile. The forest over storey was dominated by the broadleaved evergreens Laureliopsis philippiana, Aextoxicon punctatum, Eucryphia cordifolia and Nothofagus dombeyi. Availabilities of diffuse light, nitrogen, phosphorous and calcium were measured under these four over storey species, as was nutrient content of leaf litter. Advanced regeneration was sampled in plots beneath each over storey species, and results analyzed by ordination. There were significant differences in light transmission, nutritional content of leaf litter and availability of N-NO3 and P beneath the four species. Nevertheless, all nutrients showed low availability due to low mineralization and high immobilization. Ordination results indicate that the composition of advanced regeneration under N. dombeyi and L. philippiana differed from the composition of regeneration under A. punctatum or E. cordifolia. The ordination suggested that light level explained a large proportion of compositional variation. We propose that species regenerating in the understory differed more in shade tolerance than in nutritional requirements, being the light the most limiting resource in the under story

  16. Life-history traits in an evergreen Mediterranean oak respond differentially to previous experimental environments

    Directory of Open Access Journals (Sweden)

    J. M. Rey Benayas

    2008-06-01

    Full Text Available Living organisms respond both to current and previous environments, which can have important consequences on population dynamics. However, there is little experimental evidence based on long-term field studies of the effects of previous environments on the performance of individuals. We tested the hypothesis that trees that establish under different environmental conditions perform differently under similar post-establishment conditions. We used the slow-growing, evergreen Mediterranean oak Quercus ilex subsp. rotundifolia as target species. We analyzed the effects of previous environments, competition effects and tradeoffs among life-history traits (survival, growth, and reproduction. We enhanced seedling establishment for three years by reducing abiotic environmental harshness by means of summer irrigation and artificial shading in 12 experimental plots, while four plots remained as controls. Then these treatments were interrupted for ten years. Seedlings under ameliorated environmental conditions survived and grew faster during early establishment. During the post-management period, previous treatments 1 did not have any effect on survival, 2 experienced a slower above-ground growth, 3 decreased root biomass as indicated from reflectivity of Ground Penetration Radar, 4 increased acorn production mostly through a greater canopy volume and 5 increased acorn production effort. The trees exhibited a combination of effects related to acclimation for coping with abiotic stress and effects of intra-specific competition. In accordance with our hypothesis, tree performance overall depended on previous environmental conditions, and the response was different for different life-history traits. We recommend early management because it increased plot cover, shortened the time to attain sexual maturity and increased the amount of acorn production. Plots such as those assessed in this study may act as sources of propagules in deforested

  17. 76 FR 51367 - China Shipping Container Lines Co., Ltd.; COSCO Container Lines Company Limited; Evergreen Line A...

    Science.gov (United States)

    2011-08-18

    ... China Shipping Container Lines Co., Ltd.; COSCO Container Lines Company Limited; Evergreen Line A Joint Service Agreement; Hanjin Shipping Co., Ltd.; Horizon Lines, LLC; Kawasaki Kisen Kaisha, Ltd.; Nippon... Container Lines Co., Ltd.; COSCO Container Lines Company Limited; Evergreen Line A Joint Service Agreement...

  18. 75 FR 76727 - Evergreen Wind Power III, LLC; Supplemental Notice that Initial Market-Based Rate Filing Includes...

    Science.gov (United States)

    2010-12-09

    ... From the Federal Register Online via the Government Publishing Office DEPARTMENT OF ENERGY Federal Energy Regulatory Commission Evergreen Wind Power III, LLC; Supplemental Notice that Initial Market-Based... supplemental notice in the above-referenced proceeding of Evergreen Wind Power III, LLC's application for...

  19. A simple algorithm for large-scale mapping of evergreen forests in tropical America, Africa and Asia

    Science.gov (United States)

    Xiangming Xiao; Chandrashekhar M. Biradar; Christina Czarnecki; Tunrayo Alabi; Michael Keller

    2009-01-01

    The areal extent and spatial distribution of evergreen forests in the tropical zones are important for the study of climate, carbon cycle and biodiversity. However, frequent cloud cover in the tropical regions makes mapping evergreen forests a challenging task. In this study we developed a simple and novel mapping algorithm that is based on the temporal profile...

  20. The rhizospheric microbial community structure and diversity of deciduous and evergreen forests in Taihu Lake area, China.

    Directory of Open Access Journals (Sweden)

    Zhiwen Wei

    Full Text Available Soil bacteria are important drivers of biogeochemical cycles and participate in many nutrient transformations in the soil. Meanwhile, bacterial diversity and community composition are related to soil physic-chemical properties and vegetation factors. However, how the soil and vegetation factors affect the diversity and community composition of bacteria is poorly understood, especially for bacteria associated with evergreen and deciduous trees in subtropical forest ecosystems. In the present paper, the microbial communities of rhizospheric soils associated with different types of trees were analyzed by Illumina MiSeq sequencing the V3-V4 region of the 16S rRNA gene. A total of 121,219 effective 16S rRNA gene sequences were obtained, which were classified into 29 bacterial phyla and 2 archaeal phyla. The dominant phyla across all samples (>5% of good-quality sequences in each sample were Proteobacteria, Acidobacteria, Firmicutes and Bacteroidetes. The bacterial community composition and diversity were largely affected by both soil pH and tree species. The soil pH was the key factor influencing bacterial diversity, with lower pH associated with less diverse communities. Meanwhile, the contents of NO3- were higher in evergreen tree soils than those associated with deciduous trees, while less NH4+ than those associated with deciduous trees, leading to a lower pH and indirectly influencing the diversity and composition of the bacteria. The co-occurrence patterns were assessed by network analysis. A total of 415 pairs of significant and robust correlations (co-occurrence and negative were identified from 89 genera. Sixteen hubs of co-occurrence patterns, mainly under the phyla Acidobacteria, Proteobacteria, Firmicutes and Bacteroidetes, may play important roles in sustaining the stability of the rhizospheric microbial communities. In general, our results suggested that local environmental conditions and soil pH were important in shaping the bacterial

  1. Photosynthetic limitation and mechanisms of photoprotection under drought and recovery of Calotropis procera, an evergreen C3 from arid regions.

    Science.gov (United States)

    Rivas, Rebeca; Frosi, Gabriella; Ramos, Diego G; Pereira, Silvia; Benko-Iseppon, Ana M; Santos, Mauro G

    2017-09-01

    Calotropis procera is a C3 plant native from arid environmental zones. It is an evergreen, shrubby, non-woody plant with intense photosynthetic metabolism during the dry season. We measured photosynthetic parameters and leaf biochemical traits, such as gas exchange, photochemical parameters, A/Ci analysis, organic solutes, and antioxidant enzymes under controlled conditions in potted plants during drought stress, and following recovery conditions to obtain a better insight in the drought stress responses of C. procera. Indeed, different processes contribute to the drought stress resilience of C. procera and to the fast recovery after rehydration. The parameters analyzed showed that C. procera has a high efficiency for energy dissipation. The photosynthetic machinery is protected by a robust antioxidant system and photoprotective mechanisms such as alternative pathways for electrons (photorespiration and day respiration). Under severe drought stress, increased stomatal limitation and decreased biochemical limitation permitted C. procera to maintain maximum rate of Rubisco carboxylation (Vc,max) and photosynthetic rate (Amax). On the other hand, limitation of stomatal or mesophyll CO2 diffusion did not impair fast recovery, maintaining Vc,max, chloroplast CO2 concentration (Cc) and mesophyll conductance (gm) unchanged while electron flow used for RuBP carboxylation (Jc) and Amax increased. The ability to tolerate drought stress and the fast recovery of this evergreen C3 species was also due to leaf anti-oxidative stress enzyme activity, and photosynthetic pigments. Thus, these different drought tolerance mechanisms allowed high performance of photosynthetic metabolism by drought stressed plants during the re-watering period. Copyright © 2017 Elsevier Masson SAS. All rights reserved.

  2. The rhizospheric microbial community structure and diversity of deciduous and evergreen forests in Taihu Lake area, China.

    Science.gov (United States)

    Wei, Zhiwen; Hu, Xiaolong; Li, Xunhang; Zhang, Yanzhou; Jiang, Leichun; Li, Jing; Guan, Zhengbing; Cai, Yujie; Liao, Xiangru

    2017-01-01

    Soil bacteria are important drivers of biogeochemical cycles and participate in many nutrient transformations in the soil. Meanwhile, bacterial diversity and community composition are related to soil physic-chemical properties and vegetation factors. However, how the soil and vegetation factors affect the diversity and community composition of bacteria is poorly understood, especially for bacteria associated with evergreen and deciduous trees in subtropical forest ecosystems. In the present paper, the microbial communities of rhizospheric soils associated with different types of trees were analyzed by Illumina MiSeq sequencing the V3-V4 region of the 16S rRNA gene. A total of 121,219 effective 16S rRNA gene sequences were obtained, which were classified into 29 bacterial phyla and 2 archaeal phyla. The dominant phyla across all samples (>5% of good-quality sequences in each sample) were Proteobacteria, Acidobacteria, Firmicutes and Bacteroidetes. The bacterial community composition and diversity were largely affected by both soil pH and tree species. The soil pH was the key factor influencing bacterial diversity, with lower pH associated with less diverse communities. Meanwhile, the contents of NO3- were higher in evergreen tree soils than those associated with deciduous trees, while less NH4+ than those associated with deciduous trees, leading to a lower pH and indirectly influencing the diversity and composition of the bacteria. The co-occurrence patterns were assessed by network analysis. A total of 415 pairs of significant and robust correlations (co-occurrence and negative) were identified from 89 genera. Sixteen hubs of co-occurrence patterns, mainly under the phyla Acidobacteria, Proteobacteria, Firmicutes and Bacteroidetes, may play important roles in sustaining the stability of the rhizospheric microbial communities. In general, our results suggested that local environmental conditions and soil pH were important in shaping the bacterial community of the

  3. Moisture availability constraints on the leaf area to sapwood area ratio: analysis of measurements on Australian evergreen angiosperm trees

    Science.gov (United States)

    Togashi, Henrique; Prentice, Colin; Evans, Bradley; Forrester, David; Drake, Paul; Feikema, Paul; Brooksbank, Kim; Eamus, Derek; Taylor, Daniel

    2014-05-01

    The leaf area to sapwood area ratio (LA:SA) is a key plant trait that links photosynthesis to transpiration. Pipe model theory states that the sapwood cross-sectional area of a stem or branch at any point should scale isometrically with the area of leaves distal to that point. Optimization theory further suggests that LA:SA should decrease towards drier climates. Although acclimation of LA:SA to climate has been reported within species, much less is known about the scaling of this trait with climate among species. We compiled LA:SA measurements from 184 species of Australian evergreen angiosperm trees. The pipe model was broadly confirmed, based on measurements on branches and trunks of trees from one to 27 years old. We found considerable scatter in LA:SA among species. However quantile regression showed strong (0.2

  4. A Listening Laboratory Designed from Cognitive Learning Principles at Evergreen Valley College.

    Science.gov (United States)

    Johnson, Tanya

    A listening laboratory was developed at Evergreen Valley College (EVC) in accordance with procedures used at the college's individualized instruction laboratory. Steps taken in developing the laboratory included: (1) the director of the Learning Center Instructional Laboratory was interviewed to determine the procedure for establishing the…

  5. Developing an Interlibrary Loan Borrowing Policy for Evergreen Valley College Library Patrons. Governance and Management.

    Science.gov (United States)

    Poehlmann, Ruth I.

    The increased use of interlibrary loan (ILL) services at the Evergreen Valley College (EVC) library which resulted from joining OCLC automated Interlibrary Loan subsystem in 1979 led to the development of an Interlibrary Loan Borrowing Policy by the EVC library staff. The policy is designed to explain to library patrons the limitations on…

  6. A Study of Full-Time Faculty Burnout at Evergreen Valley College.

    Science.gov (United States)

    Johnson, Tanya

    In fall 1988, a study of full-time faculty and staff was conducted at Evergreen Valley College (EVC) to identify factors contributing to burnout and to create opportunities to allievate the problem. The Maslach Burnout Inventory (MBI) was used to assess the level of burnout among full-time faculty, administrators, and classified staff at EVC and…

  7. An Assessment of the Level of Faculty Burnout at Evergreen Valley College.

    Science.gov (United States)

    Johnson, Tanya

    A study was conducted at Evergreen Valley College (EVC), California, to assess the level of faculty burnout and to determine the need for personal and organizational interventions to reduce burnout and improve morale. The Maslach Burnout Inventory (MBI) was administered to all 105 full-time faculty at EVC, and scores for the MBI subscales of…

  8. A remotely sensed pigment index reveals photosynthetic phenology in evergreen conifers

    Science.gov (United States)

    John A. Gamon; K. Fred Huemmrich; Christopher Y. S. Wong; Ingo Ensminger; Steven Garrity; David Y. Hollinger; Asko Noormets; Josep Peñuelas

    2016-01-01

    In evergreen conifers, where the foliage amount changes little with season, accurate detection of the underlying “photosynthetic phenology” from satellite remote sensing has been difficult, presenting challenges for global models of ecosystem carbon uptake. Here, we report a close correspondence between seasonally changing foliar pigment levels, expressed as...

  9. Ozone uptake by an evergreen forest canopy - temporal variation and possible mechanisms

    DEFF Research Database (Denmark)

    Mikkelsen, Teis Nørgaard; Ro-Poulsen, H.; Pilegaard, K.

    2000-01-01

    Patterns of ozone concentration ([O(3)]), O(3) deposition velocity (nu(d)) and O(3) flux (F(c)) over an evergreen forest canopy are shown in relation to measuring method, physiological activity of the trees, and lime of year. The gradient and eddy correlation methods were compared and showed...

  10. Changes in structure and composition of evergreen forests on an altitudinal gradient in the Venezuelan Guayana shield.

    Science.gov (United States)

    Hernández, Lionel; Dezzeo, Nelda; Sanoja, Elio; Salazar, Leandro; Castellanos, Hernán

    2012-03-01

    There have been several ecological studies in forests of the Guayana Shield, but so far none had examined the changes in structure and composition of evergreen forests with altitude. This study describes and analyzes the structure, species composition and soil characteristics of forest stands at different altitudinal zones in Southeastern Venezuelan Guayana, in order to explain the patterns and the main factors that determine the structure and composition of evergreen forests along the altitudinal gradient. Inventories of 3 948 big (>10cm DBH) and 1 328 small (5-10cm DBH) woody stems were carried out in eleven plots, ranging from 0.1 to 1.0ha, along a 188km long transect with elevations between 290 and 1 395masl. It has been found that 1) hemiepihytes become more dominant and lianas reduce their dominance with increasing altitude and 2) the forest structure in the study area is size-dependent. Five families and 12 genera represented only 9% of the total number of families and genera, respectively, recorded troughout the gradient, but the two groups of taxa comprised more than 50% of the Importance Value (the sum of the relative density and the relative dominance) of all measured stems. Moreover, the results suggest that low species richness seems to be associated with the dominance of one or few species. Stand-level wood density (WD) of trees decreased significantly with increasing elevation. WD is an indicator of trees'life history strategy. Its decline suggests a change in the functional composition of the forest with increasing altitude. The Canonical Correspondence Analysis (CCA) indicated a distinction of the studied forests on the basis of their altitudinal levels and geographic location, and revealed different ecological responses by the forests, to environmental variables along the altitudinal gradient. The variation in species composition, in terms of basal area among stands, was controlled primarily by elevation and secondarily by rainfall and soil

  11. Changes in structure and composition of evergreen forests on an altitudinal gradient in the Venezuelan Guayana Shield

    Directory of Open Access Journals (Sweden)

    Lionel Hernández

    2012-03-01

    Full Text Available There have been several ecological studies in forests of the Guayana Shield, but so far none had examined the changes in structure and composition of evergreen forests with altitude. This study describes and analyzes the structure, species composition and soil characteristics of forest stands at different altitudinal zones in Southeastern Venezuelan Guayana, in order to explain the patterns and the main factors that determine the structure and composition of evergreen forests along the altitudinal gradient. Inventories of 3 948 big (>10cm DBH and 1 328 small (5-10cm DBH woody stems were carried out in eleven plots, ranging from 0.1 to 1.0ha, along a 188km long transect with elevations between 290 and 1 395masl. It has been found that 1 hemiepihytes become more dominant and lianas reduce their dominance with increasing altitude and 2 the forest structure in the study area is size-dependent. Five families and 12 genera represented only 9% of the total number of families and genera, respectively, recorded troughout the gradient, but the two groups of taxa comprised more than 50% of the Importance Value (the sum of the relative density and the relative dominance of all measured stems. Moreover, the results suggest that low species richness seems to be associated with the dominance of one or few species. Stand-level wood density (WD of trees decreased significantly with increasing elevation. WD is an indicator of trees’life history strategy. Its decline suggests a change in the functional composition of the forest with increasing altitude. The Canonical Correspondence Analysis (CCA indicated a distinction of the studied forests on the basis of their altitudinal levels and geographic location, and revealed different ecological responses by the forests, to environmental variables along the altitudinal gradient. The variation in species composition, in terms of basal area among stands, was controlled primarily by elevation and secondarily by rainfall

  12. Elevated ozone negatively affects photosynthesis of current-year leaves but not previous-year leaves in evergreen Cyclobalanopsis glauca seedlings.

    Science.gov (United States)

    Zhang, Weiwei; Feng, Zhaozhong; Wang, Xiaoke; Niu, Junfeng

    2014-01-01

    To assess the effects of leaf age/layer on the response of photosynthesis to chronic ozone (O3), Cyclobalanopsis glauca seedlings, a dominant evergreen broadleaf tree species in sub-tropical regions, were exposed to either ambient air (AA) or elevated O3 (AA + 60 ppb O3, E-O3) for two growing seasons in open-top chambers. Chlorophyll content, gas exchange and chlorophyll a fluorescence were investigated three times throughout the 2nd year of O3 exposure. Results indicated that E-O3 decreased photosynthetic parameters, particularly light-saturated photosynthesis rate, stomatal conductance and effective quantum yield of PSII photochemistry of current-year leaves but not previous-year leaves. Stomatal conductance of plants grown under ambient conditions partially contributed to the different response to E-O3 between leaf layers. Light radiation or other physiological and biochemical processes closely related to photosynthesis might play important roles. All suggested that leaf ages or layers should be considered when assessing O3 risk on evergreen woody species. Copyright © 2013 Elsevier Ltd. All rights reserved.

  13. Xylem traits mediate a trade-off between resistance to freeze-thaw-induced embolism and photosynthetic capacity in overwintering evergreens.

    Science.gov (United States)

    Choat, Brendan; Medek, Danielle E; Stuart, Stephanie A; Pasquet-Kok, Jessica; Egerton, John J G; Salari, Hooman; Sack, Lawren; Ball, Marilyn C

    2011-09-01

    Hydraulic traits were studied in temperate, woody evergreens in a high-elevation heath community to test for trade-offs between the delivery of water to canopies at rates sufficient to sustain photosynthesis and protection against disruption to vascular transport caused by freeze-thaw-induced embolism. Freeze-thaw-induced loss in hydraulic conductivity was studied in relation to xylem anatomy, leaf- and sapwood-specific hydraulic conductivity and gas exchange characteristics of leaves. We found evidence that a trade-off between xylem transport capacity and safety from freeze-thaw-induced embolism affects photosynthetic activity in overwintering evergreens. The mean hydraulically weighted xylem vessel diameter and sapwood-specific conductivity correlated with susceptibility to freeze-thaw-induced embolism. There was also a strong correlation of hydraulic supply and demand across species; interspecific differences in stomatal conductance and CO(2) assimilation rates were correlated linearly with sapwood- and leaf-specific hydraulic conductivity. Xylem vessel anatomy mediated an apparent trade-off between resistance to freeze-thaw-induced embolism and hydraulic and photosynthetic capacity during the winter. These results point to a new role for xylem functional traits in determining the degree to which species can maintain photosynthetic carbon gain despite freezing events and cold winter temperatures. © 2011 The Authors. New Phytologist © 2011 New Phytologist Trust.

  14. Rediscovery of Syzygium kanarense (Talbot Raizada (Myrtaceae - an endemic species of the Western Ghats, India

    Directory of Open Access Journals (Sweden)

    H.S. Shenoy

    2015-01-01

    Full Text Available Syzygium kanarense - a rare and critically endangered species of the Western Ghats has been rediscovered after a gap of 47 years from the evergreen forests of the North Kanara District, Karnataka-India. 

  15. Community composition and cellulase activity of cellulolytic bacteria from forest soils planted with broad-leaved deciduous and evergreen trees.

    Science.gov (United States)

    Yang, Jiang-Ke; Zhang, Jing-Jing; Yu, Heng-Yu; Cheng, Jian-Wen; Miao, Li-Hong

    2014-02-01

    Cellulolytic bacteria in forest soil provide carbon sources to improve the soil fertility and sustain the nutrient balance of the forest ecological system through the decomposition of cellulosic remains. These bacteria can also be utilized for the biological conversion of biomass into renewable biofuels. In this study, the community compositions and activities of cellulolytic bacteria in the soils of forests planted with broad-leaved deciduous (Chang Qing Garden, CQG) and broad-leaved evergreen (Forest Park, FP) trees in Wuhan, China were resolved through restriction fragment length polymorphism (RFLP) and sequencing analysis of the 16S rRNA gene. All of the isolates exhibited 35 RFLP fingerprint patterns and were clustered into six groups at a similarity level of 50 %. The phylogeny analysis based on the 16S rRNA gene sequence revealed that these RFLP groups could be clustered into three phylogenetic groups and further divided into six subgroups at a higher resolution. Group I consists of isolates from Bacillus cereus, Bacillus subtilis complex (I-A) and from Paenibacillus amylolyticus-related complex (I-B) and exhibited the highest cellulase activity among all of the cellulolytic bacteria isolates. Cluster II consists of isolates belonging to Microbacterium testaceum (II-A), Chryseobacterium indoltheticum (II-B), and Flavobacterium pectinovorum and the related complex (II-C). Cluster III consists of isolates belonging to Pseudomonas putida-related species. The community shift with respect to the plant species and the soil properties was evidenced by the phylogenetic composition of the communities. Groups I-A and I-B, which account for 36.0 % of the cellulolytic communities in the CQG site, are the dominant groups (88.4 %) in the FP site. Alternatively, the ratio of the bacteria belonging to group III (P. putida-related isolates) shifted from 28.0 % in CQG to 4.0 % in FP. The soil nutrient analysis revealed that the CQG site planted with deciduous broad

  16. The Next Generation Library Catalog: A Comparative Study of the OPACs of Koha, Evergreen, and Voyager

    Directory of Open Access Journals (Sweden)

    Sharon Q. Yang

    2010-09-01

    Full Text Available Open source has been the center of attention in the library world for the past several years. Koha and Evergreen are the two major open-source integrated library systems (ILSs, and they continue to grow in maturity and popularity. The question remains as to how much we have achieved in open-source development toward the next-generation catalog compared to commercial systems. Little has been written in the library literature to answer this question. This paper intends to answer this question by comparing  the next-generation features of the OPACs of two open-source ILSs (Koha and Evergreen and one proprietary ILS (Voyager’s WebVoyage.

  17. Foliar epidermal characters of some Sterculiaceae species in Nigeria

    African Journals Online (AJOL)

    DR. AWORINDE D.O

    Cola species, a tropical African genus of the family comprises 122 species which are mostly evergreen, small or moderately sized tree and is widely cultivated in tropical countries especially in Nigeria because of its economic importance. The species considered in this study are Theobroma cacao, Cola hispida Brenan &.

  18. Myxomycetes from the bark of the evergreen oak Quercus ilex

    Directory of Open Access Journals (Sweden)

    Wrigley de Basanta, Diana

    1998-06-01

    Full Text Available The results of 81 moist chamber cultures of bark from living Quercus ilex trees are reponed. A total of 37 taxa are cited, extending the number of species found on this substrate to 55. The presence of Licea deplanata on the Iberian Península is confirmed. Seven new records are included for the province of Madrid. Some data are contributed on species frequency and incubation times.Se presentan los resultados de 81 cultivos en cámara húmeda de corteza de Quercus ilex vivo. Se citan 37 táxones, que amplían a 55 el número de especies de mixomicetes encontrados sobre este sustrato. Se confirma la presencia en la Península Ibérica de Licea deplanata, y se incluyen siete nuevas citas para la provincia de Madrid. Se aportan datos sobre frecuencia de aparición y tiempos de incubación de algunas especies.

  19. The influence of canopy-layer composition on understory plant diversity in southern temperate forests

    Directory of Open Access Journals (Sweden)

    Luciana Mestre

    2017-05-01

    Full Text Available Background Understory plants represents the largest component of biodiversity in most forest ecosystems and plays a key role in forest functioning. Despite their importance, the influence of overstory-layer composition on understory plant diversity is relatively poorly understood within deciduous-evergreen broadleaved mixed forests. The aim of this work was to evaluate how tree overstory-layer composition influences on understory-layer diversity in three forest types (monospecific deciduous Nothofagus pumilio (Np, monospecific evergreen Nothofagus betuloides (Nb, and mixed N. pumilio-N. betuloides (M forests, comparing also between two geographical locations (coast and mountain to estimate differences at landscape level. Results We recorded 46 plant species: 4 ferns, 12 monocots, and 30 dicots. Canopy-layer composition influences the herb-layer structure and diversity in two different ways: while mixed forests have greater similarity to evergreen forests in the understory structural features, deciduous and mixed were similar in terms of the specific composition of plant assemblage. Deciduous pure stands were the most diverse, meanwhile evergreen stands were least diverse. Lack of exclusive species of mixed forest could represent a transition where evergreen and deciduous communities meet and integrate. Moreover, landscape has a major influence on the structure, diversity and richness of understory vegetation of pure and mixed forests likely associated to the magnitude and frequency of natural disturbances, where mountain forest not only had highest herb-layer diversity but also more exclusive species. Conclusions Our study suggests that mixed Nothofagus forest supports coexistence of both pure deciduous and pure evergreen understory plant species and different assemblages in coastal and mountain sites. Maintaining the mixture of canopy patch types within mixed stands will be important for conserving the natural patterns of understory plant

  20. Endophytic Fungi of Various Medicinal Plants Collected From Evergreen Forest Baluran National Park and Its Potential as Laboratory Manual for Mycology Course

    Directory of Open Access Journals (Sweden)

    Siti Murdiyah

    2017-03-01

    Full Text Available Endophytic fungi found on a variety of medicinal plants may express particular benefit. These fungi provide an alternative to overcome the progressive microbial resistance and as an effort to combat infectious diseases that became one of the leading causes of mortality. The main objective of this study was to isolate endophytic fungi from leaf samples of five medicinal plants species collected from evergreen forests Baluran National Park and its use as laboratory manual for Micology. Research findings showed there were 3 isolates of endophytic fungi isolated from 2 medicinal plants namely Kesambi (Schleicera oleosa and Ketapang (Terminalia catappa. All three isolates formed sporangiophores as asexual reproductive structures, while the structure of sexual still undiscovered therefore its classification has not been determined. The validity tests also showed that the lab manual is feasible for use with the percentage achievement 85.37% and 88.56%.

  1. Is Patent "Evergreening" Restricting Access to Medicine/Device Combination Products?

    Science.gov (United States)

    Beall, Reed F; Nickerson, Jason W; Kaplan, Warren A; Attaran, Amir

    2016-01-01

    Not all new drug products are truly new. Some are the result of marginal innovation and incremental patenting of existing products, but in such a way that confers no major therapeutic improvement. This phenomenon, pejoratively known as "evergreening", can allow manufacturers to preserve market exclusivity, but without significantly bettering the standard of care. Other studies speculate that evergreening is especially problematic for medicine/device combination products, because patents on the device component may outlast expired patents on the medicine component, and thereby keep competing, possibly less-expensive generic products off the market. We focused on four common conditions that are often treated by medicine/device product combinations: asthma and chronic obstructive pulmonary disease (COPD), diabetes, and severe allergic reactions. The patent data for a sample of such products (n = 49) for treating these conditions was extracted from the United States Food and Drug Administration's Orange Book. Additional patent-related data (abstracts, claims, etc) were retrieved using LexisNexis TotalPatent. Comparisons were then made between each product's device patents and medicine patents. Unexpired device patents exist for 90 percent of the 49 medicine/device product combinations studied, and were the only sort of unexpired patent for 14 products. Overall, 55 percent of the 235 patents found by our study were device patents. Comparing the last-to-expire device patent to that of the last-to-expire active ingredient patent, the median additional years of patent protection afforded by device patents was 4.7 years (range: 1.3-15.2 years). Incremental, patentable innovation in devices to extend the overall patent protection of medicine/device product combinations is very common. Whether this constitutes "evergreening" depends on whether these incremental innovations and the years of extra patent protection they confer are proportionately matched by therapeutic

  2. A new species of Stigmatomma from Taiwan (Hymenoptera, Formicidae, Amblyoponinae).

    Science.gov (United States)

    Hsu, Feng-Chuan; Esteves, Flavia A; Chou, Lien-Siang; Lin, Chung-Chi

    2017-01-01

    Stigmatomma is the most speciose ant genus in the subfamily Amblyoponinae. In the present paper, the worker caste of a new species is described, S. luyiaesp. n., which was collected from a soil sample in a subtropical evergreen broad-leaved forest in Taiwan. An identification key to the females of Stigmatomma species with 11 antennomeres occurring in Asia is also provided.

  3. From leaf longevity to canopy seasonality: a carbon optimality phenology model for tropical evergreen forests

    Science.gov (United States)

    Xu, X.; Medvigy, D.; Wu, J.; Wright, S. J.; Kitajima, K.; Pacala, S. W.

    2016-12-01

    Tropical evergreen forests play a key role in the global carbon, water and energy cycles. Despite apparent evergreenness, this biome shows strong seasonality in leaf litter and photosynthesis. Recent studies have suggested that this seasonality is not directly related to environmental variability but is dominated by seasonal changes of leaf development and senescence. Meanwhile, current terrestrial biosphere models (TBMs) can not capture this pattern because leaf life cycle is highly underrepresented. One challenge to model this leaf life cycle is the remarkable diversity in leaf longevity, ranging from several weeks to multiple years. Ecologists have proposed models where leaf longevity is regarded as a strategy to optimize carbon gain. However previous optimality models can not be readily integrated into TBMs because (i) there are still large biases in predicted leaf longevity and (ii) it is never tested whether the carbon optimality model can capture the observed seasonality in leaf demography and canopy photosynthesis. In this study, we develop a new carbon optimality model for leaf demography. The novelty of our approach is two-fold. First, we incorporate a mechanistic photosynthesis model that can better estimate leaf carbon gain. Second, we consider the interspecific variations in leaf senescence rate, which strongly influence the modelled optimal carbon gain. We test our model with a leaf trait database for Panamanian evergreen forests. Then, we apply the model at seasonal scale and compare simulated seasonality of leaf litter and canopy photosynthesis with in-situ observations from several Amazonian forest sites. We find that (i) compared with original optimality model, the regression slope between observed and predicted leaf longevity increases from 0.15 to 1.04 in our new model and (ii) that our new model can capture the observed seasonal variations of leaf demography and canopy photosynthesis. Our results suggest that the phenology in tropical evergreen

  4. Estructura y regeneración bajo distintas propuestas de manejo de bosques de Nothofagus pumilio (Poepp et. Endl) Krasser en Tierra del Fuego, Argentina

    OpenAIRE

    Cellini, Juan Manuel

    2010-01-01

    La regeneración es un proceso dinámico basado en la incorporación de nuevos individuos a medida que otros desaparecen como resultado de la mortalidad natural. Sus fases comprenden la producción de semillas, la dispersión y la germinación. Nothofagus pumilio (Poepp. et Endl.) Krasser es considerada una especie de tolerancia media, ya que la regeneración presenta una tolerancia a la luz, no puede reproducirse ni sobrevivir por largos períodos bajo una alta cobertura y por sus habilidades de col...

  5. Relationships between the timing of budburst, plant traits, and distribution of 24 coexisting woody species in a warm-temperate forest in Japan.

    Science.gov (United States)

    Osada, Noriyuki

    2017-04-01

    Timing of budburst (DBB) may be related to the functional traits and distributions of woody species in temperate regions. Although many previous studies have investigated DBB in a number of temperate species, it has seldom been linked to multiple plant trait relationships. DBB and plant traits were investigated for 24 woody species for 2 years in a warm-temperate secondary forest in Japan. Particular attention was paid to differences in trait relationships between coexisting deciduous and evergreen broad-leaved species. DBB was correlated with plant traits in deciduous but not evergreen broad-leaved species; DBB was later for deciduous species with greater leaf mass, leaf area, vessel diameter, and leaf nitrogen content per unit mass. In addition, DBB was later for species with more northern distributions in deciduous and evergreen species. Clear differences in the trait relationships between deciduous and evergreen broad-leaved species might be caused by different selection pressures on DBB; selection is expected to be more severe in deciduous species. Overall, the continuous variable of vessel diameter might be used as a simple and effective trait to predict DBB of deciduous species regardless of wood anatomy; however, no such traits were detected as effective predictors of DBB in evergreen species at this study site. In addition, DBB was earlier for the species of more southern distributions, suggesting that such species benefit more from warming. © 2017 Botanical Society of America.

  6. Vegetation shift from deciduous to evergreen dwarf shrubs in response to selective herbivory offsets carbon losses: evidence from 19 years of warming and simulated herbivory in the subarctic tundra.

    Science.gov (United States)

    Ylänne, Henni; Stark, Sari; Tolvanen, Anne

    2015-10-01

    Selective herbivory of palatable plant species provides a competitive advantage for unpalatable plant species, which often have slow growth rates and produce slowly decomposable litter. We hypothesized that through a shift in the vegetation community from palatable, deciduous dwarf shrubs to unpalatable, evergreen dwarf shrubs, selective herbivory may counteract the increased shrub abundance that is otherwise found in tundra ecosystems, in turn interacting with the responses of ecosystem carbon (C) stocks and CO2 balance to climatic warming. We tested this hypothesis in a 19-year field experiment with factorial treatments of warming and simulated herbivory on the dominant deciduous dwarf shrub Vaccinium myrtillus. Warming was associated with a significantly increased vegetation abundance, with the strongest effect on deciduous dwarf shrubs, resulting in greater rates of both gross ecosystem production (GEP) and ecosystem respiration (ER) as well as increased C stocks. Simulated herbivory increased the abundance of evergreen dwarf shrubs, most importantly Empetrum nigrum ssp. hermaphroditum, which led to a recent shift in the dominant vegetation from deciduous to evergreen dwarf shrubs. Simulated herbivory caused no effect on GEP and ER or the total ecosystem C stocks, indicating that the vegetation shift counteracted the herbivore-induced C loss from the system. A larger proportion of the total ecosystem C stock was found aboveground, rather than belowground, in plots treated with simulated herbivory. We conclude that by providing a competitive advantage to unpalatable plant species with slow growth rates and long life spans, selective herbivory may promote aboveground C stocks in a warming tundra ecosystem and, through this mechanism, counteract C losses that result from plant biomass consumption. © 2015 John Wiley & Sons Ltd.

  7. Leaf ontogeny and demography explain photosynthetic seasonality in Amazon evergreen forests

    Science.gov (United States)

    Wu, J.; Albert, L.; Lopes, A. P.; Restrepo-Coupe, N.; Hayek, M.; Wiedemann, K. T.; Guan, K.; Stark, S. C.; Prohaska, N.; Tavares, J. V.; Marostica, S. F.; Kobayashi, H.; Ferreira, M. L.; Campos, K.; Silva, R. D.; Brando, P. M.; Dye, D. G.; Huxman, T. E.; Huete, A. R.; Nelson, B. W.; Saleska, S. R.

    2015-12-01

    Photosynthetic seasonality couples the evolutionary ecology of plant leaves to large-scale rhythms of carbon and water exchanges that are important feedbacks to climate. However, the extent, magnitude, and controls on photosynthetic seasonality of carbon-rich tropical forests are poorly resolved, controversial in the remote sensing literature, and inadequately represented in most earth system models. Here we show that ecosystem-scale phenology (measured by photosynthetic capacity), rather than environmental seasonality, is the primary driver of photosynthetic seasonality at four Amazon evergreen forests spanning gradients in rainfall seasonality, forest composition, and flux seasonality. We further demonstrate that leaf ontogeny and demography explain most of this ecosystem phenology at two central Amazon evergreen forests, using a simple leaf-cohort canopy model that integrates eddy covariance-derived CO2 fluxes, novel near-surface camera-detected leaf phenology, and ground observations of litterfall and leaf physiology. The coordination of new leaf growth and old leaf divestment (litterfall) during the dry season shifts canopy composition towards younger leaves with higher photosynthetic efficiency, driving large seasonal increases (~27%) in ecosystem photosynthetic capacity. Leaf ontogeny and demography thus reconciles disparate observations of forest seasonality from leaves to eddy flux towers to satellites. Strategic incorporation of such whole-plant coordination processes as phenology and ontogeny will improve ecological, evolutionary and earth system theories describing tropical forests structure and function, allowing more accurate representation of forest dynamics and feedbacks to climate in earth system models.

  8. Morfología y Anatomía del Ápice Caulinar de Nothofagus dombeyi (Nothofagaceae a lo largo de un año Morfology and anatomy of the shoot apex of Nothofagus dombeyi (Nothofagaceae along a year

    Directory of Open Access Journals (Sweden)

    Soledad García

    2006-07-01

    Full Text Available En el presente estudio se evaluó la posible variación anual de la morfología y la anatomía del ápice caulinar de coihue, Nothofagus dombeyi (Nothofagaceae. A partir de muestras tomadas a lo largo de un año calendario, se realizaron cortes longitudinales de las yemas terminales con micrótomo de congelación. Independientemente de la época del año, una yema terminal está conformada por un meristema apical y rudimentos de tallo y hojas. Los primordios foliares proximales tienen mayor tamaño y grado de diferenciación que los distales. En la axila de cada estípula se destaca la presencia de coléteres. Cada coléter se comunica vascularmente con la estípula correspondiente. El número de primordios foliares por yema es constante entre abril y octubre y disminuye posteriormente al incrementarse el número de hojas expandidas, aunque sin llegar a cero. Al final de la estación de crecimiento se distinguen yemas de mayor y yemas de menor tamaño; estas últimas se secan y desprenden del tallo antes de la primavera siguiente. Dentro de una yema se evidencian, en un momento dado, distintos grados de diferenciación entre primordios foliares proximales y distales y entre la lámina y las estípulas de los primordios más proximales.The present study evaluates the possible annual variation in the morphology and anatomy of the shoot apex of Nothofagus dombeyi (Nothofagaceae. From samples taken over one year, longitudinal slices of terminal buds were cut with a freezing microtome. Irrespective of the time of the year, a terminal bud consists of an apical meristem and rudiments of stem and leaves. Proximal primordia are larger and have a higher degree of differentiation than distal primordia. Around the axil of each stipule colleters are present. Each colleter is connected with the corresponding stipule through a conducting strand. The number of leaf primordia per bud is constant between April and October and diminishes later on as leaf expansion

  9. Encapsulated Somatic Embryos and Zygotic Embryos for Obtaining Artificial Seeds of Rauli-Beech (Nothofagus alpina (Poepp. & Endl. Oerst. Encapsulado de Embriones Somáticos y Embriones Cigóticos para Obtención de Semillas Artificiales de Raulí (Nothofagus alpina (Poepp. & Endl. Oerst.

    Directory of Open Access Journals (Sweden)

    Priscila Cartes R

    2009-03-01

    Full Text Available Somatic and zygotic embryos from mature seeds of rauli-beech, Nothofagus alpina (Poepp. & Endl. Oerst., were encapsulated in different artificial endosperms in order to generate a cover that fulfills the function of nourishment and protection of the embryos, facilitating their later germination. The content of sodium alginate varied by 4%, 3%, and 2%, as did the immersion time in calcium chloride (CaCl2, which acts as complexing agent. The artificial endosperm components of the Murashige and Skoog medium (MS were added, supplemented with 0.5 mg L-1 indolacetic acid (IAA, 0.5 mg L-1 naphthaleneacetic acid (NAA, 2 mg L-1 6-benzylaminopurine (BAP and 30 g L-1 sucrose. The germinative behaviors of encapsulated somatic and zygotic embryos were evaluated after 4 wk. Comparing the percentages of germination reached by encapsulated somatic and zygotic embryos it was observed that they had similar germinative behavior according to the type of encapsulation applied. However, zygotic embryos substantially exceeded the germination levels reached by somatic embryos, 100% vs. 45% respectively.Embriones somáticos y cigóticos provenientes de semillas maduras de raulí, Nothofagus alpina (Poepp. & Endl. Oerst., se encapsularon en diferentes endospermas sintéticos con el fin de generar una cubierta que cumpla la función de nutrir y proteger al embrión para facilitar su posterior germinación. Se varió el contenido de alginato de sodio al 4%, 3% y 2% y el tiempo de inmersión en cloruro de calcio (CaCl2, el que actúa como agente acomplejante. Además, a la matriz artificial se adicionaron componentes del medio Murashige y Skoog (MS suplementado con: 0,5 mg L-1 de indolacetic acid (IAA, 0,5 mg L-1 de ácido naftalenacético (NAA, 2 mg L-1 de 6-bencilaminopurina (BAP y 30 gL-1 de sacarosa. Al cabo de 4 semanas el porcentaje de germinación de los embriones somáticos y cigóticos encapsulados tuvieron similar comportamiento germinativo según el tipo de

  10. Exploring variation in leaf mass per area (LMA) from leaf to cell: an anatomical analysis of 26 woody species.

    Science.gov (United States)

    Villar, Rafael; Ruiz-Robleto, Jeannete; Ubera, José Luis; Poorter, Hendrik

    2013-10-01

    Plant species differ widely in the leaf biomass invested per unit area (LMA). LMA can be explained by variation in leaf thickness and/or density, both of which are influenced by anatomical tissue composition. The aim of this study is to quantify the anatomical characteristics that underlie variation in LMA in a range of woody species. • Twenty-six woody species, forming 13 species pairs with a deciduous and evergreen species from the same genus or family, were grown in a glasshouse. The youngest full-grown leaves were analyzed for LMA and morpho-anatomical characteristics at leaf, tissue, and cell level. • Considered over all species studied, leaf thickness and density were equally important to explain the variation in LMA, but the class difference between deciduous and evergreen species was mainly determined by thickness, whereas variation within each group was largely due to density. Evergreens had thicker leaves, predominantly caused by a larger volume of mesophyll and air spaces, whereas the higher leaf density within each group was due to a lower proportion of epidermis and air spaces, and overall smaller cells. • The anatomical basis for variation in LMA in woody species depends on the contrast made. Higher LMA in evergreens is mainly due to a greater leaf thickness, caused by a larger volume of mesophyll and air spaces. Within deciduous species and evergreens, higher LMA is caused by a higher density, due to higher volumetric fractions of mesophyll and lower fractions of air spaces and epidermis.

  11. Improving winter leaf area index estimation in evergreen coniferous forests and its significance in carbon and water fluxes modeling

    Science.gov (United States)

    Wang, R.; Chen, J. M.; Luo, X.

    2016-12-01

    Modeling of carbon and water fluxes at the continental and global scales requires remotely sensed LAI as inputs. For evergreen coniferous forests (ENF), severely underestimated winter LAI has been one of the issues for mostly available remote sensing products, which could cause negative bias in the modeling of Gross Primary Productivity (GPP) and evapotranspiration (ET). Unlike deciduous trees which shed all the leaves in winter, conifers retains part of their needles and the proportion of the retained needles depends on the needle longevity. In this work, the Boreal Ecosystem Productivity Simulator (BEPS) was used to model GPP and ET at eight FLUXNET Canada ENF sites. Two sets of LAI were used as the model inputs: the 250m 10-day University of Toronto (U of T) LAI product Version 2 and the corrected LAI based on the U of T LAI product and the needle longevity of the corresponding tree species at individual sites. Validating model daily GPP (gC/m2) against site measurements, the mean RMSE over eight sites decreases from 1.85 to 1.15, and the bias changes from -0.99 to -0.19. For daily ET (mm), mean RMSE decreases from 0.63 to 0.33, and the bias changes from -0.31 to -0.16. Most of the improvements occur in the beginning and at the end of the growing season when there is large correction of LAI and meanwhile temperature is still suitable for photosynthesis and transpiration. For the dormant season, the improvement in ET simulation mostly comes from the increased interception of precipitation brought by the elevated LAI during that time. The results indicate that model performance can be improved by the application the corrected LAI. Improving the winter RS LAI can make a large impact on land surface carbon and energy budget.

  12. Constructing seasonal LAI trajectory by data-model fusion for global evergreen needle-leaf forests

    Science.gov (United States)

    Wang, R.; Chen, J.; Mo, G.

    2010-12-01

    For decades, advancements in optical remote sensors made it possible to produce maps of a biophysical parameter--the Leaf Area Index (LAI), which is critically necessary in regional and global modeling of exchanges of carbon, water, energy and other substances, across large areas in a fast way. Quite a few global LAI products have been generated since 2000, e.g. GLOBCARBON (Deng et al., 2006), MODIS Collection 5 (Shabanov et al., 2007), CYCLOPES (Baret et al., 2007), etc. Albeit these progresses, the basic physics behind the technology restrains it from accurate estimation of LAI in winter, especially for northern high-latitude evergreen needle-leaf forests. Underestimation of winter LAI in these regions has been reported in literature (Yang et al., 2000; Cohen et al., 2003; Tian et al., 2004; Weiss et al., 2007; Pisek et al., 2007), and the distortion is usually attributed to the variations of canopy reflectance caused by understory change (Weiss et al., 2007) as well as by the presence of ice and snow on leaves and ground (Cohen, 2003; Tian et al., 2004). Seasonal changes in leaf pigments can also be another reason for low LAI retrieved in winter. Low conifer LAI values in winter retrieved from remote sensing make them unusable for surface energy budget calculations. To avoid these drawbacks of remote sensing approaches, we attempt to reconstruct the seasonal LAI trajectory through model-data fusion. A 1-degree LAI map of global evergreen needle-leaf forests at 10-day interval is produced based on the carbon allocation principle in trees. With net primary productivity (NPP) calculated by the Boreal Ecosystems Productivity Simulator (BEPS) (Chen et al., 1999), carbon allocated to needles is quantitatively evaluated and then can be further transformed into LAI using the specific leaf area (SLA). A leaf-fall scheme is developed to mimic the carbon loss caused by falling needles throughout the year. The seasonally maximum LAI from remote sensing data for each pixel

  13. A Comparative Analysis To Determine the Value in Producing Higher Achievement in a Social Studies Course at Evergreen Valley College.

    Science.gov (United States)

    Griffin, Jerome J.

    The major purpose of this study was to determine if students enrolled in an "Eyes on the Prize" telecourse performed better academically in utilizing a study guide than students who did not utilize the study guide. "Eyes on the Prize," a course offered at Evergreen Valley College (EVC), fulfills a two-year ethnic studies…

  14. Genetic diversity and seed production in Santa Lucia fir (Abies bracteata),a relict of the Miocene broadleaved evergreen forest

    Science.gov (United States)

    F. Thomas Ledig; Paul D. Hodgskiss; David R. Johnson

    2006-01-01

    Santa Lucia fir (Abies bracteata), is a unique fir, the sole member of the subgenus Pseudotorreya. It is a relict of the Miocene broadleaved evergreen sclerophyll forest, and is now restricted to a highly fragmented range in the Santa Lucia Mountains of central coastal California. Expected heterozygosity for 30 isozyme loci in 18 enzyme systems...

  15. Leaf adaptations of evergreen and deciduous trees of semi-arid and humid savannas on three continents

    NARCIS (Netherlands)

    Tomlinson, K.W.; Poorter, L.; Sterck, F.J.; Borghetti, M.; Ward, D.; Bie, de S.; Langevelde, van F.

    2013-01-01

    1. Drought stress selects for a suite of plant traits at root, stem and leaf level. Two strategies are proposed for trees growing in seasonally water-stressed environments: drought tolerance and drought avoidance. These are respectively associated with evergreen phenology, where plants retain their

  16. Leaf development and demography explain photosynthetic seasonality in Amazon evergreen forests

    Science.gov (United States)

    Wu, Jin; Albert, Lauren; Lopes, Aline; Restrepo-Coupe, Natalia; Hayek, Matthew; Wiedemann, Kenia T.; Guan, Kaiyu; Stark, Scott C.; Christoffersen, Bradley; Prohaska, Neill; Tavares, Julia V.; Marostica, Suelen; Kobayashi, Hideki; Ferreira, Maurocio L.; Campos, Kleber Silva; da Silva, Rodrigo; Brando, Paulo M.; Dye, Dennis G.; Huxman, Travis E.; Huete, Alfredo; Nelson, Bruce; Saleska, Scott

    2016-01-01

    In evergreen tropical forests, the extent, magnitude, and controls on photosynthetic seasonality are poorly resolved and inadequately represented in Earth system models. Combining camera observations with ecosystem carbon dioxide fluxes at forests across rainfall gradients in Amazônia, we show that aggregate canopy phenology, not seasonality of climate drivers, is the primary cause of photosynthetic seasonality in these forests. Specifically, synchronization of new leaf growth with dry season litterfall shifts canopy composition toward younger, more light-use efficient leaves, explaining large seasonal increases (~27%) in ecosystem photosynthesis. Coordinated leaf development and demography thus reconcile seemingly disparate observations at different scales and indicate that accounting for leaf-level phenology is critical for accurately simulating ecosystem-scale responses to climate change.

  17. Molecular phylogeography and ecological niche modelling of a widespread herbaceous climber, Tetrastigma hemsleyanum (Vitaceae): insights into Plio-Pleistocene range dynamics of evergreen forest in subtropical China.

    Science.gov (United States)

    Wang, Yi-Han; Jiang, Wei-Mei; Comes, Hans Peter; Hu, Feng Sheng; Qiu, Ying-Xiong; Fu, Cheng-Xin

    2015-04-01

    Warm-temperate evergreen (WTE) forest represents the typical vegetation type of subtropical China, but how its component species responded to past environmental change remains largely unknown. Here, we reconstruct the evolutionary history of Tetrastigma hemsleyanum, an herbaceous climber restricted to the WTE forest. Twenty populations were genotyped using chloroplast DNA sequences and nuclear microsatellite loci to assess population structure and diversity, supplemented by phylogenetic dating, ancestral area reconstructions and ecological niche modeling (ENM) of the species distributions during the Last Glacial Maximum (LGM) and at present. Lineages in Southwest vs Central-South-East China diverged through climate/tectonic-induced vicariance of an ancestral southern range during the early Pliocene. Long-term stability in the Southwest contrasts with latitudinal range shifts in the Central-South-East region during the early-to-mid-Pleistocene. Genetic and ENM data strongly suggest refugial persistence in situ at the LGM. Pre-Quaternary environmental changes appear to have had a persistent influence on the population genetic structure of this subtropical WTE forest species. Our findings suggest relative demographic stability of this biome in China over the last glacial-interglacial cycle, in contrast with palaeobiome reconstructions showing that this forest biome retreated to areas of today's tropical South China during the LGM. © 2015 The Authors. New Phytologist © 2015 New Phytologist Trust.

  18. Genetic diversity of an endangered species, Fokienia hodginsii ...

    African Journals Online (AJOL)

    ajl yemi

    2011-11-14

    Nov 14, 2011 ... Fokienia hodginsii (Cupressaceae) is distributed in montane evergreen forests in North and Central. Vietnam and extends to southeastern China at 900 m above sea level. The species has been threatened in its area of distribution in recent years because of habitat destruction and over-exploitation. The.

  19. Genetic diversity of an endangered species, Fokienia hodginsii ...

    African Journals Online (AJOL)

    Fokienia hodginsii (Cupressaceae) is distributed in montane evergreen forests in North and Central Vietnam and extends to southeastern China at 900 m above sea level. The species has been threatened in its area of distribution in recent years because of habitat destruction and over-exploitation. The genetic variation of ...

  20. Long-term experimental warming, shading and nutrient addition affect the concentration of phenolic compounds in arctic-alpine deciduous and evergreen dwarf shrubs

    DEFF Research Database (Denmark)

    Hansen, Anja Hoff; Jonasson, Sven Evert; Michelsen, Anders

    2006-01-01

    -arctic, alpine ecosystem, we investigated the effects on carbon based secondary compounds (CBSC) and nitrogen in one dominant deciduous dwarf shrub, Salix herbacea × polaris and two dominant evergreen dwarf shrubs, Cassiope tetragona and Vaccinium vitis-idaea throughout one growing season. The main aims were....... herbacea × polaris than in the corresponding current year's leaf cohort of the evergreen C. tetragona. The changes were also much higher than in the 1-year-old leaves of the two evergreens probably due to differences in dilution and turnover of CBSC in growing and mature leaves paired with different rates...

  1. Distribution patterns of the subtropical evergreen broad-leaved forests of southwestern China, as compared with those of the eastern Chinese subtropical regions

    Directory of Open Access Journals (Sweden)

    Tang, C. Q.

    2015-12-01

    Full Text Available This paper analyzes the geographic distribution patterns of the subtropical evergreen broad-leaved forests of southwestern China, and compares with other subtropical regions in the east of China in terms of forest types, pertinent species, and spatial distribution along latitudinal, longitudinal and altitudinal gradients. In general, for both the western and the eastern subtropical regions, the evergreen broad-leaved forests are dominated by species of Castanopsis, Lithocarpus, Cyclobalanopsis (Fagaceae, Machilus, Cinnamomum (Lauraceae, Schima (Theaceae, Manglietia, and Michelia, (Magnoliaceae, while in southwestern China there are more diverse forest types including semi-humid, monsoon, mid-montane moist and humid evergreen broad-leaved forests, but only monsoon and humid forests in the east. The Yunnan area has more varied species of Lithocarpus or Cyclobalanopsis or Castanopsis as dominants than does eastern China, where the chief dominant genus is Castanopsis. The upper limits of the evergreen broad-leaved forests are mainly 2400–2800 m in western Yunnan and western Sichuan, much higher than in eastern China (600–1500, but 2500 m in Taiwan. Also discussed are the environmental effects on plant diversity of the evergreen broad-leaved forest ecosystems exemplified by Yunnan and Taiwan.En este trabajo se analiza los patrones de distribución geográfica de los bosques subtropicales perennifolios de hoja ancha del suroeste de china, y se comparan con los de otras regiones subtropicales del este de China en términos de tipología de bosque, especies relevantes, y distribución espacial a lo largo de un gradiente latitudinal, longitudinal y altitudinal. De manera general, los bosques perennifolios de hoja ancha de la regiones subtropicales tanto orientales como occidentales presentan dominancia de especies de Castanopsis, Lithocarpus, Cyclobalanopsis (Fagaceae, Machilus, Cinnamomum (Lauraceae, Schima (Theaceae, Manglietia y Michelia

  2. Teledetección satelital cuantitativa para estimar el área basal del bosque de Nothofagus pumilio (Nothofagaceae: El rol del índice de área foliar como información auxiliar Quantitative remote sensing to estimate basal area in Nothofagus pumilio (Nothofagaceae forest: The role of leaf area index as ancillary information

    Directory of Open Access Journals (Sweden)

    GASTÓN M DÍAZ

    2011-12-01

    Full Text Available Los bosques de lenga (Nothofagus pumilio son el recurso forestal más importante de la región andino patagónica argentina, sin embargo, para implementar planes de manejo en pos de prevenir o revertir su degradación es necesario disponer de mayor información sobre su estructura. Una alternativa para obtener esa información es relacionar datos satelitales con las características del bosque a través de modelos físicos y estadísticos. Pero, ¿cuál es el método más eficaz? El índice de área foliar (IAF se encuentra relacionado con la reflectividad del dosel vegetal a través del modelo de transferencia radiativa PROSAIL, lo que permite desarrollar técnicas de teledetección satelital para estimar el IAF con bases físicas, en vez de con modelos estadísticos. De ese modo se puede aprovechar la relación empírico-biológica existente entre el IAF y la estructura del bosque para estimar el área basal. El objetivo principal fue comparar la exactitud de tres métodos para estimar el área basal de la lenga con datos SPOT-5. Los métodos comparados fueron: estadístico directo (ED, estadístico de dos pasos (E2P y físico-estadístico de dos pasos (FE2P. La exactitud fue evaluada con 24 parcelas no involucradas en el ajuste o calibración de los modelos. No se hallaron diferencias significativas en la exactitud de la alternativa físico-estadística en comparación con las netamente estadísticas. Sin embargo, en base al análisis conjunto de los resultados y lo reportado por otros investigadores, se concluye que la ventaja de utilizar modelos físicos radica en la mayor robustez de la estimación y no en la mayor exactitud.Lenga forests (Nothofagus pumilio are the most important forest resource of the Argentinean Andean Patagonia, however, more information about their structure is needed to implement forest management policies and practices in order to prevent their degradation and revert it. One option to obtain this kind of information

  3. Endogenous Quantification of Abscisic Acid and Indole-3-Acetic Acid in Somatic and Zigotic Embryos of Nothofagus alpina (Poepp. & Endl. Oerst Cuantificación Endógena de Ácido Abscísico y Ácido Indol-3 Acético en Embriones Somáticos y Cigóticos de Nothofagus alpina (Poepp. & Endl. Oerst

    Directory of Open Access Journals (Sweden)

    Pricila Cartes Riquelme

    2011-12-01

    Full Text Available Abscisic acid (ABA and indole-3-acetic acid (IAA participate in the propagation of plants by somatic embryogenesis, causing polar structural differentiation of the embryo. The goal of the assay was to compare endogenous levels of ABA and IAA between somatic embryos (SE and zygotic embryos (ZE of Nothofagus alpina (Poepp. & Endl. Oerst. In this study, a somatic embryo maturation assay involving the addition of varying concentrations of exogenous ABA was performed on cotyledonary-stage of N. alpina. Furthermore, the endogenous levels of ABA and IAA were quantified in the immature ZE, the mature ZE, and the embryonic axis of a mature embryo of N. alpina. The current study utilized high performance liquid chromatography (HPLC for quantification. The maturation treatments performed did not present significant differences in the endogenous ABA levels in SE. However, significant differences did exist in levels of ABA and IAA between SE submitted to the different maturation treatments and mature ZE of N. alpina. The application of exogenous ABA to the culture medium increased endogenous ABA levels, therefore, increasing the number of germinated somatic embryos. Thus, the plant conversion process was also successfully completed in somatic embryos of N. alpina.El ácido abscísico (ABA y el ácido indol 3 acético (IAA participan en el proceso de propagación de plantas mediante embriogénesis somática, ya que permiten la diferenciación de la estructura polar del embrión, órganos y regiones meristemáticas de éste. En este estudio se llevó a cabo un ensayo de maduración de embriones somáticos en estado cotiledonar con la adición de diferentes concentraciones de ABA exógeno, además se determinaron niveles endógenos entre ZE inmaduro, ZE maduro, y eje embrionario aislado desde el embrión maduro para luego comparar niveles endógenos de ABA e IAA en embriones somáticos (SE y cigóticos (ZE de raulí, Nothofagus alpina (Poepp. & Endl. Oerst. La

  4. A new species of Alsodes (Anura: Alsodidae) from Altos de Cantillana, central Chile.

    Science.gov (United States)

    Charrier, Andrés; Correa, Claudio; Castro, Camila; Méndez, Marco A

    2015-02-05

    Based on morphological and molecular evidence (mitochondrial and nuclear sequences) we describe a new species of spiny-chest frog, Alsodes cantillanensis, from central Chile (around 34°S). The type locality, Quebrada Infiernillo, is located in the Coastal Range at approximately 65 km from Santiago (Metropolitan Region), the capital of Chile. The distribution of the new species is included entirely in that of A. nodosus (32-36°S approximately), which was identified as the sister taxon according to molecular phylogenetic analyses. Moreover, both species are sympatric in the type locality. The new species was found in a Nothofagus macrocarpa relict forest potentially threatened by gold mining activities. We identify other threats for its conservation and some biological data needed for understanding the evolution of this species. This discovery reveals the scarce knowledge about biogeography, evolution and ecology of spiny-chest frogs from central Chile. 

  5. Changes in structure and composition of evergreen forests on an altitudinal gradient in the Venezuelan Guayana Shield

    Directory of Open Access Journals (Sweden)

    Lionel Hernández

    2012-03-01

    Full Text Available There have been several ecological studies in forests of the Guayana Shield, but so far none had examined the changes in structure and composition of evergreen forests with altitude. This study describes and analyzes the structure, species composition and soil characteristics of forest stands at different altitudinal zones in Southeastern Venezuelan Guayana, in order to explain the patterns and the main factors that determine the structure and composition of evergreen forests along the altitudinal gradient. Inventories of 3 948 big (>10cm DBH and 1 328 small (5-10cm DBH woody stems were carried out in eleven plots, ranging from 0.1 to 1.0ha, along a 188km long transect with elevations between 290 and 1 395masl. It has been found that 1 hemiepihytes become more dominant and lianas reduce their dominance with increasing altitude and 2 the forest structure in the study area is size-dependent. Five families and 12 genera represented only 9% of the total number of families and genera, respectively, recorded troughout the gradient, but the two groups of taxa comprised more than 50% of the Importance Value (the sum of the relative density and the relative dominance of all measured stems. Moreover, the results suggest that low species richness seems to be associated with the dominance of one or few species. Stand-level wood density (WD of trees decreased significantly with increasing elevation. WD is an indicator of trees’life history strategy. Its decline suggests a change in the functional composition of the forest with increasing altitude. The Canonical Correspondence Analysis (CCA indicated a distinction of the studied forests on the basis of their altitudinal levels and geographic location, and revealed different ecological responses by the forests, to environmental variables along the altitudinal gradient. The variation in species composition, in terms of basal area among stands, was controlled primarily by elevation and secondarily by rainfall

  6. Aplicación de relaciones de densidad-diámetro y de área potencial aprovechable en bosques de Nothofagus Dombeyi (mirb.) Oerst, como herramientas de planificación silvícola .

    OpenAIRE

    Cruz Johnson, Pablo Christian

    2013-01-01

    Uno de los objetivos de esta tesis de doctorado fue analizar la aplicación de relaciones de densidad ¿ diámetro en bosques de Nothofagus dombeyi (Mirb.) oerst, para la localidad del Río Mirta en la XI Región de Chile, como herramientas de planificación silvícola. El método de análisis consistió en la generación de una muestra de densidad¿diámetro a partir de la que se determinó el índice de densidad máximo (IDmax) a partir del cual se estimaron las máximas densidades que la especie podría alc...

  7. The rhizospheric microbial community structure and diversity of deciduous and evergreen forests in Taihu Lake area, China

    OpenAIRE

    Wei, Zhiwen; Hu, Xiaolong; Li, Xunhang; Zhang, Yanzhou; Jiang, Leichun; Li, Jing; Guan, Zhengbing; Cai, Yujie; Liao, Xiangru

    2017-01-01

    Soil bacteria are important drivers of biogeochemical cycles and participate in many nutrient transformations in the soil. Meanwhile, bacterial diversity and community composition are related to soil physic-chemical properties and vegetation factors. However, how the soil and vegetation factors affect the diversity and community composition of bacteria is poorly understood, especially for bacteria associated with evergreen and deciduous trees in subtropical forest ecosystems. In the present p...

  8. Do photosynthetic limitations of evergreen Quercus ilex leaves change with long-term increased drought severity?

    Science.gov (United States)

    Limousin, Jean-Marc; Misson, Laurent; Lavoir, Anne-Violette; Martin, Nicolas K; Rambal, Serge

    2010-05-01

    Seasonal drought can severely impact leaf photosynthetic capacity. This is particularly important for Mediterranean forests, where precipitation is expected to decrease as a consequence of climate change. Impacts of increased drought on the photosynthetic capacity of the evergreen Quercus ilex were studied for two years in a mature forest submitted to long-term throughfall exclusion. Gas exchange and chlorophyll fluorescence were measured on two successive leaf cohorts in a control and a dry plot. Exclusion significantly reduced leaf water potential in the dry treatment. In both treatments, light-saturated net assimilation rate (A(max)), stomatal conductance (g(s)), maximum carboxylation rate (V(cmax)), maximum rate of electron transport (J(max)), mesophyll conductance to CO2 (g(m)) and nitrogen investment in photosynthesis decreased markedly with soil water limitation during summer. The relationships between leaf photosynthetic parameters and leaf water potential remained identical in the two treatments. Leaf and canopy acclimation to progressive, long-term drought occurred through changes in leaf area index, leaf mass per area and leaf chemical composition, but not through modifications of physiological parameters.

  9. Changes to intellectual property policy in South Africa: putting a stop to evergreening?

    Science.gov (United States)

    Hill, Julia E

    2014-08-01

    South Africa is a middle-income country with the world's largest HIV patient cohort and a growing burden of communicable and non-communicable diseases - a prime location for pharmaceutical companies looking to expand their markets. Yet, 20 years after the country's first democratic elections, poor health indicators and an over-burdened public health system belie persistently stark levels of socioeconomic inequality. As the South African government revises national intellectual property (IP) policies, the pharmaceutical industry and global access to medicines movement are watching, aware of ramifications South Africa's actions will have on patent laws and the availability of generic medicines in other middle-income countries and across Africa. South Africa's draft IP policy is meeting fierce resistance from industry, although proposed reforms are compliant with the Agreement on trade related aspects of intellectual property (TRIPS) and in line with on-going policies and actions of both developing and developed countries. Could the establishment of a patent examination system and new patentability criteria rein in evergreening and lead to lower medicine prices? What will be the potential impact of reform on medical innovation? And why is it both necessary and urgent that the South African government seek a fairer balance between private and public interests?

  10. Simulation of rainfall interception using multilayer model in evergreen broadleaf forest, Cambodia

    Science.gov (United States)

    Nobuhiro, T.; Shimizu, A.; Tanaka, K.; Kabeya, N.; Tamai, K.; Chann, S.; Keth, N.

    2006-12-01

    The proportion of forest area is relatively high in Cambodia compared with neighboring countries. Therefore forest is one of the important factors on the water cycle in this country. The rainfall interception by a tree canopy and evaporation after the rainfall event are one of the important factors for considering such a water cycle. To clarify those processes, a rainfall interception measurement plot (25 x 25 m) was constructed in the evergreen broadleaf forest area in Kampong Thom province, central part of Cambodia. We measured rainfall, through fall and stem flow in the interception plot, and then we analyzed the relationship between those components. Moreover, the simulation of rainfall interception was carried out using multilayer model. Model parameters such as canopy structure and leaf characteristics were estimated using observed interception components and meteorological elements during large rainfall event. Annual rainfall interception was reproduced using multilayer model with obtained parameters and observed meteorological elements. The simulation results were in agreement with the observed value. The rainfall interception rate in the interception plot was considered to be about 15 % against annual rainfall.

  11. Increasing carbon discrimination rates and depth of water uptake favor the growth of Mediterranean evergreen trees in the ecotone with temperate deciduous forests.

    Science.gov (United States)

    Barbeta, Adrià; Peñuelas, Josep

    2017-12-01

    Tree populations at the low-altitudinal or -latitudinal limits of species' distributional ranges are predicted to retreat toward higher altitudes and latitudes to track the ongoing changes in climate. Studies have focused on the climatic sensitivity of the retreating species, whereas little is known about the potential replacements. Competition between tree species in forest ecotones will likely be strongly influenced by the ecophysiological responses to heat and drought. We used tree-ring widths and δ13 C and δ18 O chronologies to compare the growth rates and long-term ecophysiological responses to climate in the temperate-Mediterranean ecotone formed by the deciduous Fagus sylvatica and the evergreen Quercus ilex at the low altitudinal and southern latitudinal limit of F. sylvatica (NE Iberian Peninsula). F. sylvatica growth rates were similar to those of other southern populations and were surprisingly not higher than those of Q. ilex, which were an order of magnitude higher than those in nearby drier sites. Higher Q. ilex growth rates were associated with high temperatures, which have increased carbon discrimination rates in the last 25 years. In contrast, stomatal regulation in F. sylvatica was proportional to the increase in atmospheric CO2 . Tree-ring δ18 O for both species were mostly correlated with δ18 O in the source water. In contrast to many previous studies, relative humidity was not negatively correlated with tree-ring δ18 O but had a positive effect on Q. ilex tree-ring δ18 O. Furthermore, tree-ring δ18 O decreased in Q. ilex over time. The sensitivity of Q. ilex to climate likely reflects the uptake of deep water that allowed it to benefit from the effect of CO2 fertilization, in contrast to the water-limited F. sylvatica. Consequently, Q. ilex is a strong competitor at sites currently dominated by F. sylvatica and could be favored by increasingly warmer conditions. © 2017 John Wiley & Sons Ltd.

  12. Descomposición de hojarasca de Pinus radiata y tres especies arbóreas nativas Decomposition of leaf litter of Pinus radiata and three native tree species

    Directory of Open Access Journals (Sweden)

    CHRISTOPHER H. LUSK

    2001-09-01

    -central Chile to exotic tree plantations. However, little is known about the effects of these wholesale landuse changes on ecosystem properties and processes, with the notable exception of studies of site water balance. In this brief communication, we present the results of a comparative study of decomposition of leaf litter of Pinus radiata and three common native tree species, beneath exotic and native woody vegetation in south-central Chile. We aimed to assess the nutrient cycling implications of substitution or invasion of native vegetation by P. radiata. Litter samples of the four species were incubated in both environments, registering the percentage of dry weight loss after two and six months. Decomposition rates of all species were much faster during the first two months of incubation than during the four subsequent months. At both dates there were significant differences between species and between sites, with faster decomposition of all species beneath P. radiata. There was no evidence of interaction between species and site. After six months, species rank order for the percentage of weight loss was Nothofagus obliqua > P. radiata > Peumus boldus > Cryptocarya alba. Interspecific variation in decomposition rates was more closely correlated with specific leaf area than with litter nitrogen content. Given that litter of P. radiata decomposed slower than that of the deciduous N. obliqua, but faster than the sclerophyll evergreens, the consequences of substitution or invasion for decomposition processes are likely to depend on the composition of the native vegetation in question

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

    Science.gov (United States)

    Du, X.; Guo, Q.; Gao, X.; Ma, K.

    2007-01-01

    Understanding the seed rain and seed loss dynamics in the natural condition has important significance for revealing the natural regeneration mechanisms. We conducted a 3-year field observation on seed rain, seed loss and natural regeneration of Castanopsis fargesii Franch., a dominant tree species in evergreen broad-leaved forests in Dujiangyan, southwestern China. The results showed that: (1) there were marked differences in (mature) seed production between mast (733,700 seeds in 2001) and regular (51,200 and 195,600 seeds in 2002 and 2003, respectively) years for C. fargesii. (2) Most seeds were dispersed in leaf litter, humus and 0-2 cm depth soil in seed bank. (3) Frequency distributions of both DBH and height indicated that C. fargesii had a relatively stable population. (4) Seed rain, seed ground density, seed loss, and leaf fall were highly dynamic and certain quantity of seeds were preserved on the ground for a prolonged time due to predator satiation in both the mast and regular years so that the continuous presence of seed bank and seedling recruitments in situ became possible. Both longer time observations and manipulative experiments should be carried out to better understand the roles of seed dispersal and regeneration process in the ecosystem performance. ?? 2006 Elsevier B.V. All rights reserved.

  14. Biogeographic variation in evergreen conifer needle longevity and impacts on boreal forest carbon cycle projections.

    Science.gov (United States)

    Reich, Peter B; Rich, Roy L; Lu, Xingjie; Wang, Ying-Ping; Oleksyn, Jacek

    2014-09-23

    Leaf life span is an important plant trait associated with interspecific variation in leaf, organismal, and ecosystem processes. We hypothesized that intraspecific variation in gymnosperm needle traits with latitude reflects both selection and acclimation for traits adaptive to the associated temperature and moisture gradient. This hypothesis was supported, because across 127 sites along a 2,160-km gradient in North America individuals of Picea glauca, Picea mariana, Pinus banksiana, and Abies balsamea had longer needle life span and lower tissue nitrogen concentration with decreasing mean annual temperature. Similar patterns were noted for Pinus sylvestris across a north-south gradient in Europe. These differences highlight needle longevity as an adaptive feature important to ecological success of boreal conifers across broad climatic ranges. Additionally, differences in leaf life span directly affect annual foliage turnover rate, which along with needle physiology partially regulates carbon cycling through effects on gross primary production and net canopy carbon export. However, most, if not all, global land surface models parameterize needle longevity of boreal evergreen forests as if it were a constant. We incorporated temperature-dependent needle longevity and %nitrogen, and biomass allocation, into a land surface model, Community Atmosphere Biosphere Land Exchange, to assess their impacts on carbon cycling processes. Incorporating realistic parameterization of these variables improved predictions of canopy leaf area index and gross primary production compared with observations from flux sites. Finally, increasingly low foliage turnover and biomass fraction toward the cold far north indicate that a surprisingly small fraction of new biomass is allocated to foliage under such conditions.

  15. [Influences of petrophytia moss on vegetation development in evergreen broad-leaved forest].

    Science.gov (United States)

    Wang, Zhongsheng; Fang, Yanming

    2003-06-01

    In order to examine the role of Petrophytia moss in maintaining the stability and integrity of forest vegetation, the distribution patterns of vascular plants among Petrophytia moss layer were investigated in five heterogeneous patches of evergreen broad-leaved forest at Longwangshan, Zhejiang Province. The distribution and composition of vascular plants were jointly affected by various factors, such as disturbance degree in patch, moss growth condition, and water and soil conservation ability of moss layer. Original habitats patch 1 and patch 5 were kept well, and hence, the even depth, dry weight and maximum water-holding capacity of moss layer, as well as the dry weight of soil and the soil water-absorbing rate in moss layer for patch 1 and patch 5 were much more than other patches. For example, the even depth (cm) of moss layer were decreased in the order of patch 5(2.2) > patch 1(2.0) > patch 2(1.5) > patch 3(1.1) > patch 4(0.9); the ranking of vascular plant diversities among moss layer in each patch was patch 5(16) > patch 1(14) > patch 3(9) > patch 4(7), and the general cover of these plants was followed as patch 3(30.0%) > patch 1(28.5%) > patch 5 (26.5%) > patch 2 (17.0%) > patch 4(4.5%). It was concluded that Petrophytia moss had the roles of reserving water and soil, holding litter, concentrating nutrient elements, and corrupting rock, which could improve the environmental condition of rock surface, help to the regeneration of vascular plants, and bring positive effects on the restoration or conversation of vegetation in disturbance sites and on the extension of forest scale.

  16. A new species of Rhytidognathus (Carabidae, Migadopini from Argentina

    Directory of Open Access Journals (Sweden)

    Sergio Roig-Junent

    2012-11-01

    Full Text Available The Migadopini are a small tribe of Carabidae with 47 species that occur in South America, Australia, and New Zealand, in the sub-Antarctic areas. In South America, most of the genera inhabit areas related to sub-Antartic Nothofagus forest except two monogeneric genera, the Ecuadorian genus Aquilex Moret and the Pampean genus Rhytidognathus Chaudoir. These two genera are geographically isolated from the remaining five South American genera. New material of Rhytidognathus from the northeast of Buenos Aires province and from Entre Ríos province permits establishing that the previous records of Rhytidognathus ovalis (Dejean for Argentina were erroneous and that it belongs to a new species. Based on external morphological characters and from male and female genitalia we describe Rhytidognathus platensis as a new species. In this contribution we provide illustrations, keys, habitat characteristics and some biogeographic considerations on the distribution of Rhytidognathus.

  17. Impact of evergreening on patients and health insurance: a meta analysis and reimbursement cost analysis of citalopram/escitalopram antidepressants.

    Science.gov (United States)

    Alkhafaji, Ali A; Trinquart, Ludovic; Baron, Gabriel; Desvarieux, Moïse; Ravaud, Philippe

    2012-11-20

    "Evergreening" refers to the numerous strategies whereby owners of pharmaceutical products use patent laws and minor drug modifications to extend their monopoly privileges on the drug. We aimed to evaluate the impact of evergreening through the case study of the antidepressant citalopram and its chiral switch form escitalopram by evaluating treatment efficacy and acceptability for patients, as well as health insurance costs for society. To assess efficacy and acceptability, we performed meta-analyses for efficacy and acceptability. We compared direct evidence (meta-analysis of results of head-to-head trials) and indirect evidence (adjusted indirect comparison of results of placebo-controlled trials). To assess health insurance costs, we analyzed individual reimbursement data from a representative sample of the French National Health Insurance Inter-regime Information System (SNIIR-AM) from 2003 to 2010, which allowed for projecting these results to the whole SNIIR-AM population (53 million people). In the meta-analysis of seven head-to-head trials (2,174 patients), efficacy was significantly better for escitalopram than citalopram (combined odds ratio (OR) 1.60 (95% confidence interval 1.05 to 2.46)). However, for the adjusted indirect comparison of 10 citalopram and 12 escitalopram placebo-controlled trials, 2,984 and 3,777 patients respectively, efficacy was similar for the two drug forms (combined indirect OR 1.03 (0.82 to 1.30)). Because of the discrepancy, we could not combine direct and indirect data (test of inconsistency, P = 0.07). A similar discrepancy was found for treatment acceptability. The overall reimbursement cost burden for the citalopram, escitalopram and its generic forms was 120.6 million Euros in 2010, with 96.8 million Euros for escitalopram. The clinical benefit of escitalopram versus citalopram remains uncertain. In our case of evergreening, escitalopram represented a substantially high proportion of the overall reimbursement cost burden as

  18. Evaluation of shrub species for sheep grazing in the Strandveld of ...

    African Journals Online (AJOL)

    The production of three exotic shrub species, Atriplex nummularia (old man saltbush), A. canescens (four-winged saltbush) and Medicago arborea (tree lucerne) and one indigenous evergreen shrub, Chrysanthemoides monilifera subsp. pisifera (west coast bitou), was evaluated in the Strandveld of the Cape West Coast in ...

  19. Changes to southern Appalachian water yield and stormflow after loss of a foundation species

    Science.gov (United States)

    Steven T. Brantley; Chelcy Ford Miniat; Katherine J. Elliott; Stephanie H. Laseter; James M. Vose

    2014-01-01

    Few studies have examined how insect outbreaks affect landscape-level hydrologic processes. We report the hydrologic effects of the invasive, exotic hemlock woolly adelgid (HWA) in a headwater catchment in the southern Appalachian Mountains. The study watershed experienced complete mortality of an evergreen tree species, Tsuga canadensis (L.) Carr. (...

  20. Factors promoting larch dominance in central Siberia: fire versus growth performance and implications for carbon dynamics at the boundary of evergreen and deciduous conifers

    Directory of Open Access Journals (Sweden)

    E.-D. Schulze

    2012-04-01

    Full Text Available The relative role of fire and of climate in determining canopy species composition and aboveground carbon stocks were investigated. Measurements were made along a transect extending from the dark taiga zone of central Siberia, where Picea and Abies dominate the canopy, into the Larix zone of eastern Siberia. We test the hypotheses that the change in canopy species composition is based (1 on climate-driven performance only, (2 on fire only, or (3 on fire-performance interactions. We show that the evergreen conifers Picea obovata and Abies sibirica are the natural late-successional species both in central and eastern Siberia, provided there has been no fire for an extended period of time. There are no changes in performance of the observed species along the transect. Fire appears to be the main factor explaining the dominance of Larix and of soil carbon. Of lesser influence were longitude as a proxy for climate, local hydrology and active-layer thickness. We can only partially explain fire return frequency, which is not only related to climate and land cover, but also to human behavior.

    Stand-replacing fires decreased from 300 to 50 yrs between the Yenisei Ridge and the upper Tunguska. Repeated non-stand-replacing surface fires eliminated the regeneration of Abies and Picea. With every 100 yrs since the last fire, the percentage of Larix decreased by 20%.

    Biomass of stems of single trees did not show signs of age-related decline. Relative diameter increment was 0.41 ± 0.20% at breast height and stem volume increased linearly over time with a rate of about 0.36 t C ha−1 yr−1 independent of age class and species. Stand biomass reached about 130 t C ha−1(equivalent to about 520 m3 ha−1. Individual trees of Larix were older than 600 yrs. The maximum age and biomass seemed to be limited by fungal rot of

  1. Factors promoting larch dominance in central Siberia: fire versus growth performance and implications for carbon dynamics at the boundary of evergreen and deciduous conifers

    Science.gov (United States)

    Schulze, E.-D.; Wirth, C.; Mollicone, D.; von Lüpke, N.; Ziegler, W.; Achard, F.; Mund, M.; Prokushkin, A.; Scherbina, S.

    2012-04-01

    The relative role of fire and of climate in determining canopy species composition and aboveground carbon stocks were investigated. Measurements were made along a transect extending from the dark taiga zone of central Siberia, where Picea and Abies dominate the canopy, into the Larix zone of eastern Siberia. We test the hypotheses that the change in canopy species composition is based (1) on climate-driven performance only, (2) on fire only, or (3) on fire-performance interactions. We show that the evergreen conifers Picea obovata and Abies sibirica are the natural late-successional species both in central and eastern Siberia, provided there has been no fire for an extended period of time. There are no changes in performance of the observed species along the transect. Fire appears to be the main factor explaining the dominance of Larix and of soil carbon. Of lesser influence were longitude as a proxy for climate, local hydrology and active-layer thickness. We can only partially explain fire return frequency, which is not only related to climate and land cover, but also to human behavior. Stand-replacing fires decreased from 300 to 50 yrs between the Yenisei Ridge and the upper Tunguska. Repeated non-stand-replacing surface fires eliminated the regeneration of Abies and Picea. With every 100 yrs since the last fire, the percentage of Larix decreased by 20%. Biomass of stems of single trees did not show signs of age-related decline. Relative diameter increment was 0.41 ± 0.20% at breast height and stem volume increased linearly over time with a rate of about 0.36 t C ha-1 yr-1 independent of age class and species. Stand biomass reached about 130 t C ha-1(equivalent to about 520 m3 ha-1). Individual trees of Larix were older than 600 yrs. The maximum age and biomass seemed to be limited by fungal rot of heart wood. 60% of old Larix and Picea and 30% of Pinus sibirica trees were affected by stem rot. Implications for the future role of fire and of plant diseases are

  2. Influence of summer marine fog and low cloud stratus on water relations of evergreen woody shrubs (Arctostaphylos: Ericaceae) in the chaparral of central California.

    Science.gov (United States)

    Vasey, Michael C; Loik, Michael E; Parker, V Thomas

    2012-10-01

    Mediterranean-type climate (MTC) regions around the world are notable for cool, wet winters and hot, dry summers. A dominant vegetation type in all five MTC regions is evergreen, sclerophyllous shrubland, called chaparral in California. The extreme summer dry season in California is moderated by a persistent low-elevation layer of marine fog and cloud cover along the margin of the Pacific coast. We tested whether late dry season water potentials (Ψ(min)) of chaparral shrubs, such as Arctostaphylos species in central California, are influenced by this coast-to-interior climate gradient. Lowland coastal (maritime) shrubs were found to have significantly less negative Ψ(min) than upland interior shrubs (interior), and stable isotope (δ(13)C) values exhibited greater water use efficiency in the interior. Post-fire resprouter shrubs (resprouters) had significantly less negative Ψ(min) than co-occurring obligate seeder shrubs (seeders) in interior and transitional chaparral, possibly because resprouters have deeper root systems with better access to subsurface water than shallow-rooted seeders. Unexpectedly, maritime resprouters and seeders did not differ significantly in their Ψ(min), possibly reflecting more favorable water availability for shrubs influenced by the summer marine layer. Microclimate and soil data also suggest that maritime habitats have more favorable water availability than the interior. While maritime seeders constitute the majority of local Arctostaphylos endemics, they exhibited significantly greater vulnerability to xylem cavitation than interior seeders. Because rare seeders in maritime chaparral are more vulnerable to xylem cavitation than interior seeders, the potential breakdown of the summer marine layer along the coast is of potential conservation concern.

  3. Impact of evergreening on patients and health insurance: a meta analysis and reimbursement cost analysis of citalopram/escitalopram antidepressants

    Directory of Open Access Journals (Sweden)

    Alkhafaji Ali A

    2012-11-01

    Full Text Available Abstract Background "Evergreening" refers to the numerous strategies whereby owners of pharmaceutical products use patent laws and minor drug modifications to extend their monopoly privileges on the drug. We aimed to evaluate the impact of evergreening through the case study of the antidepressant citalopram and its chiral switch form escitalopram by evaluating treatment efficacy and acceptability for patients, as well as health insurance costs for society. Methods To assess efficacy and acceptability, we performed meta-analyses for efficacy and acceptability. We compared direct evidence (meta-analysis of results of head-to-head trials and indirect evidence (adjusted indirect comparison of results of placebo-controlled trials. To assess health insurance costs, we analyzed individual reimbursement data from a representative sample of the French National Health Insurance Inter-regime Information System (SNIIR-AM from 2003 to 2010, which allowed for projecting these results to the whole SNIIR-AM population (53 million people. Results In the meta-analysis of seven head-to-head trials (2,174 patients, efficacy was significantly better for escitalopram than citalopram (combined odds ratio (OR 1.60 (95% confidence interval 1.05 to 2.46. However, for the adjusted indirect comparison of 10 citalopram and 12 escitalopram placebo-controlled trials, 2,984 and 3,777 patients respectively, efficacy was similar for the two drug forms (combined indirect OR 1.03 (0.82 to 1.30. Because of the discrepancy, we could not combine direct and indirect data (test of inconsistency, P = 0.07. A similar discrepancy was found for treatment acceptability. The overall reimbursement cost burden for the citalopram, escitalopram and its generic forms was 120.6 million Euros in 2010, with 96.8 million Euros for escitalopram. Conclusions The clinical benefit of escitalopram versus citalopram remains uncertain. In our case of evergreening, escitalopram represented a substantially

  4. In the right place at the right time: habitat representation in protected areas of South American Nothofagus-dominated plants after a dispersal constrained climate change scenario.

    Science.gov (United States)

    Alarcón, Diego; Cavieres, Lohengrin A

    2015-01-01

    In order to assess the effects of climate change in temperate rainforest plants in southern South America in terms of habitat size, representation in protected areas, considering also if the expected impacts are similar for dominant trees and understory plant species, we used niche modeling constrained by species migration on 118 plant species, considering two groups of dominant trees and two groups of understory ferns. Representation in protected areas included Chilean national protected areas, private protected areas, and priority areas planned for future reserves, with two thresholds for minimum representation at the country level: 10% and 17%. With a 10% representation threshold, national protected areas currently represent only 50% of the assessed species. Private reserves are important since they increase up to 66% the species representation level. Besides, 97% of the evaluated species may achieve the minimum representation target only if the proposed priority areas were included. With the climate change scenario representation levels slightly increase to 53%, 69%, and 99%, respectively, to the categories previously mentioned. Thus, the current location of all the representation categories is useful for overcoming climate change by 2050. Climate change impacts on habitat size and representation of dominant trees in protected areas are not applicable to understory plants, highlighting the importance of assessing these effects with a larger number of species. Although climate change will modify the habitat size of plant species in South American temperate rainforests, it will have no significant impact in terms of the number of species adequately represented in Chile, where the implementation of the proposed reserves is vital to accomplish the present and future minimum representation. Our results also show the importance of using migration dispersal constraints to develop more realistic future habitat maps from climate change predictions.

  5. In the right place at the right time: habitat representation in protected areas of South American Nothofagus-dominated plants after a dispersal constrained climate change scenario.

    Directory of Open Access Journals (Sweden)

    Diego Alarcón

    Full Text Available In order to assess the effects of climate change in temperate rainforest plants in southern South America in terms of habitat size, representation in protected areas, considering also if the expected impacts are similar for dominant trees and understory plant species, we used niche modeling constrained by species migration on 118 plant species, considering two groups of dominant trees and two groups of understory ferns. Representation in protected areas included Chilean national protected areas, private protected areas, and priority areas planned for future reserves, with two thresholds for minimum representation at the country level: 10% and 17%. With a 10% representation threshold, national protected areas currently represent only 50% of the assessed species. Private reserves are important since they increase up to 66% the species representation level. Besides, 97% of the evaluated species may achieve the minimum representation target only if the proposed priority areas were included. With the climate change scenario representation levels slightly increase to 53%, 69%, and 99%, respectively, to the categories previously mentioned. Thus, the current location of all the representation categories is useful for overcoming climate change by 2050. Climate change impacts on habitat size and representation of dominant trees in protected areas are not applicable to understory plants, highlighting the importance of assessing these effects with a larger number of species. Although climate change will modify the habitat size of plant species in South American temperate rainforests, it will have no significant impact in terms of the number of species adequately represented in Chile, where the implementation of the proposed reserves is vital to accomplish the present and future minimum representation. Our results also show the importance of using migration dispersal constraints to develop more realistic future habitat maps from climate change predictions.

  6. Within-tree variation in transpiration in isolated evergreen oak trees: evidence in support of the pipe model theory.

    Science.gov (United States)

    Infante, J M; Mauchamp, A; Fernández-Alé, R; Joffre, R; Rambal, S

    2001-04-01

    Within-tree variation in sap flow density (SFD) was measured in two isolated evergreen oak (Quercus ilex L.) trees growing in an oak savannah (dehesa) in southwest Spain. Sap flow was estimated by the constant heating method. Three sensors were installed in the trunk of each tree in three orientations: northeast (NE), northwest (NW) and south (S). Sap flow density was monitored continuously from May 18 to September 27, 1993. Daily values of SFD ranged between 500 and 4500 mm3 mm-2 day-1. There were significant differences in SFD between orientations; SFD was higher in the NE and NW orientations than in the S orientation. These differences were noted on both a daily and seasonal time scale, and were less pronounced on cloudy days and at the end of the drought period, when SFD was relatively low. Our results support the idea that branches of trees can be viewed as a collection of small independent plants.

  7. Detecting Inter-Annual Variations in the Phenology of Evergreen Conifers Using Long-Term MODIS Vegetation Index Time Series

    Science.gov (United States)

    Ulsig, Laura; Nichol, Caroline J.; Huemmrich, Karl F.; Landis, David R.; Middleton, Elizabeth M.; Lyapustin, Alexei I.; Mammarella, Ivan; Levula, Janne; Porcar-Castell, Albert

    2017-01-01

    Long-term observations of vegetation phenology can be used to monitor the response of terrestrial ecosystems to climate change. Satellite remote sensing provides the most efficient means to observe phenological events through time series analysis of vegetation indices such as the Normalized Difference Vegetation Index (NDVI). This study investigates the potential of a Photochemical Reflectance Index (PRI), which has been linked to vegetation light use efficiency, to improve the accuracy of MODIS-based estimates of phenology in an evergreen conifer forest. Timings of the start and end of the growing season (SGS and EGS) were derived from a 13-year-long time series of PRI and NDVI based on a MAIAC (multi-angle implementation of atmospheric correction) processed MODIS dataset and standard MODIS NDVI product data. The derived dates were validated with phenology estimates from ground-based flux tower measurements of ecosystem productivity. Significant correlations were found between the MAIAC time series and ground-estimated SGS (R (sup 2) equals 0.36-0.8), which is remarkable since previous studies have found it difficult to observe inter-annual phenological variations in evergreen vegetation from satellite data. The considerably noisier NDVI product could not accurately predict SGS, and EGS could not be derived successfully from any of the time series. While the strongest relationship overall was found between SGS derived from the ground data and PRI, MAIAC NDVI exhibited high correlations with SGS more consistently (R (sup 2) is greater than 0.6 in all cases). The results suggest that PRI can serve as an effective indicator of spring seasonal transitions, however, additional work is necessary to confirm the relationships observed and to further explore the usefulness of MODIS PRI for detecting phenology.

  8. Seasonal variations in nutrients and secondary metabolites in semi-arid savannas depend on year and species

    CSIR Research Space (South Africa)

    Scogings, PF

    2015-03-01

    Full Text Available years, including one ‘wet’ year (above-average rainfall) and two ‘dry’ years (below-average rainfall). Neither N nor P consistently decreased during wet seasons, while CBSMs did not consistently increase. Neither N nor P in the evergreen species...

  9. Physiological Effects of Smoke Exposure on Deciduous and Conifer Tree Species

    Directory of Open Access Journals (Sweden)

    W. John Calder

    2010-01-01

    Full Text Available Smoke from forest fires can persist in the environment for weeks and while there is a substantial amount of literature examining the effects of smoke exposure on seed germination, the effects of smoke on leaf function are nearly uninvestigated. The objective of this study was to compare growth and primary and secondary metabolic responses of deciduous angiosperm and evergreen conifer tree species to short smoke exposure. Twenty minutes of smoke exposure resulted in a greater than 50% reduction in photosynthetic capacity in five of the six species we examined. Impairment of photosynthesis in response to smoke was a function of reductions in stomatal conductance and biochemical limitations. In general, deciduous angiosperm species showed a greater sensitivity than evergreen conifers. While there were significant decreases in photosynthesis and stomatal conductance, smoke had no significant effect on growth or secondary defense compound production in any of the tree species examined.

  10. Topographic variation in aboveground biomass in a subtropical evergreen broad-leaved forest in China.

    Directory of Open Access Journals (Sweden)

    Dunmei Lin

    Full Text Available The subtropical forest biome occupies about 25% of China, with species diversity only next to tropical forests. Despite the recognized importance of subtropical forest in regional carbon storage and cycling, uncertainties remain regarding the carbon storage of subtropical forests, and few studies have quantified within-site variation of biomass, making it difficult to evaluate the role of these forests in the global and regional carbon cycles. Using data for a 24-ha census plot in east China, we quantify aboveground biomass, characterize its spatial variation among different habitats, and analyse species relative contribution to the total aboveground biomass of different habitats. The average aboveground biomass was 223.0 Mg ha(-1 (bootstrapped 95% confidence intervals [217.6, 228.5] and varied substantially among four topographically defined habitats, from 180.6 Mg ha(-1 (bootstrapped 95% CI [167.1, 195.0] in the upper ridge to 245.9 Mg ha(-1 (bootstrapped 95% CI [238.3, 253.8] in the lower ridge, with upper and lower valley intermediate. In consistent with our expectation, individual species contributed differently to the total aboveground biomass of different habitats, reflecting significant species habitat associations. Different species show differently in habitat preference in terms of biomass contribution. These patterns may be the consequences of ecological strategies difference among different species. Results from this study enhance our ability to evaluate the role of subtropical forests in the regional carbon cycle and provide valuable information to guide the protection and management of subtropical broad-leaved forest for carbon sequestration and carbon storage.

  11. Mineralización del nitrógeno, carbono y actividad enzimática del suelo en un bosque de Nothofagus obliqua (Mirb Oerst y una plantación de Pinus radiata D. Don. del centro-sur de Chile Nitrogen and carbon mineralization and enzyme activity in soils of Nothofagus obliqua (Mirb Oerst stands and Pinus radiata D. Don plantation in south-central Chile

    Directory of Open Access Journals (Sweden)

    YESSICA RIVAS

    2009-03-01

    Full Text Available En Chile, el establecimiento de plantaciones comerciales de rápido crecimiento ha sido sostenido en las últimas décadas mediante la sustitución de bosques nativos y conversión de suelos agrícolas. Pinus radiata D. Don es la principal especie productiva, debido a su crecimiento acelerado y adaptabilidad al clima y los suelos. En el presente estudio se plantea que la actividad biológica del suelo es variable a través del año, en respuesta a variaciones de precipitación, temperatura y contenido de humedad de suelo y que el cambio de uso de suelo desde un bosque templado de Nothofagus obliqua (Mirb Oerst a una plantación con coniferas exóticas, modifica la química del suelo y consecuentemente los procesos de N-min, C-min y la actividad biológica del suelo. Esta hipótesis fue examinada en un bosque de N. obliqua y una plantación de P. radiata del centro-sur de Chile (40°07' S, 72° O. Se evaluó mensualmente la tasa mineralización de nitrógeno (N-min, cabono (C-min y la actividad enzimática potencial del suelo (ureasa, proteasa e hidrólisis de la fluoresceína diacetato entre septiembre 2003 y mayo 2005. Los resultados demuestran que los niveles de las variables de actividad biológica del suelo fueron significativamente diferentes entre las parcelas de bosque y plantación (Lambda de Wilk = 0,022; F 5,80 = 733; P In Chile, commercial forests plantations have increased during the last decades due in part to replacement of native forests and conversion of agricultural soils. Pinus radiata D. Don has been the main tree planted, due to its rapid growth and adaptability. In the present study we proposed that biological activity varies along the year due to changes of precipitation, temperature and soil water content and mainly because the conversion of native forest to exotic P. radiata plantations alters the soil chemistry, N and C mineralization and the potential enzymatic activity in these soils. This hypothesis was examined in a

  12. Seedling growth in greenhouse conditions of the forest species Dialium guianense (Aubl.) Sandwith

    OpenAIRE

    Georgina Vargas Simon; Reinaldo Pire; Martha Olivia Lazaro Dzul

    2018-01-01

    Dialium guianense is used for its wood and fruit production, and is a tropical tree species native to evergreen forests. Given the threat these forests face, the purpose of this work was to evaluate the initial growth of the plant under greenhouse conditions, for aiming in the development of propagation programs. Seedlings of the species were transplanted to nursery bags under a completely randomized design and grown for 10 months with an initial population of 200 plants. At the end of the ex...

  13. The Mediterranean evergreen Quercus ilex and the semi-deciduous Cistus albidus differ in their leaf gas exchange regulation and acclimation to repeated drought and re-watering cycles.

    Science.gov (United States)

    Galle, Alexander; Florez-Sarasa, Igor; Aououad, Hanan El; Flexas, Jaume

    2011-10-01

    Plants may exhibit some degree of acclimation after experiencing drought, but physiological adjustments to consecutive cycles of drought and re-watering (recovery) have scarcely been studied. The Mediterranean evergreen holm oak (Q. ilex) and the semi-deciduous rockrose (C. albidus) showed some degree of acclimation after the first of three drought cycles (S1, S2, and S3). For instance, during S2 and S3 both species retained higher relative leaf water contents than during S1, despite reaching similar leaf water potentials. However, both species showed remarkable differences in their photosynthetic acclimation to repeated drought cycles. Both species decreased photosynthesis to a similar extent during the three cycles (20-40% of control values). However, after S1 and S2, photosynthesis recovered only to 80% of control values in holm oak, due to persistently low stomatal (g(s)) and mesophyll (g(m)) conductances to CO(2). Moreover, leaf intrinsic water use efficiency (WUE) was kept almost constant in this species during the entire experiment. By contrast, photosynthesis of rockrose recovered almost completely after each drought cycle (90-100% of control values), while the WUE was largely and permanently increased (by 50-150%, depending on the day) after S1. This was due to a regulation which consisted in keeping g(s) low (recovering to 50-60% of control values after re-watering) while maintaining a high g(m) (even exceeding control values during re-watering). While the mechanisms to achieve such particular regulation of water and CO(2) diffusion in leaves are unknown, it clearly represents a unique acclimation feature of this species after a drought cycle, which allows it a much better performance during successive drought events. Thus, differences in the photosynthetic acclimation to repeated drought cycles can have important consequences on the relative fitness of different Mediterranean species or growth forms within the frame of climate change scenarios.

  14. Comparing growth phenology of co-occurring deciduous and evergreen conifers exposed to drought.

    Science.gov (United States)

    Swidrak, Irene; Schuster, Roman; Oberhuber, Walter

    2013-12-01

    Plant phenological events are influenced by climate factors such as temperature and rainfall. To evaluate phenological responses to water availability in a Spring Heath-Pine wood (Erico-Pinetum typicum), the focus of this study was to determine intra-annual dynamics of apical and lateral growth of co-occurring early successional Larix decidua and Pinus sylvestris and late successional Picea abies exposed to drought. The effect of reduced plant water availability on growth phenology was investigated by conducting a rainfall exclusion experiment. Timing of key phenological dates (onset, maximum rate, end, duration) of growth processes were compared among species at the rain-sheltered and control plot during 2011 and 2012. Shoot and needle elongation were monitored on lateral branches in the canopy at c. 16 m height and radial growth was recorded by automatic dendrometers at c. 1.3 m height of > 120 yr old trees. Different sequences in aboveground growth phenology were detected among the three species under the same growing conditions. While onset of radial growth in April through early May was considerably preceded by onset of needle growth in Larix decidua (5 - 6 weeks) and shoot growth in Pinus sylvestris (c. 3 weeks), it occurred quite simultaneously with onset of shoot growth in Picea abies. Low water availability had a minor impact on onset of aboveground growth, which is related to utilization of stored water, but caused premature cessation of aboveground growth. At the control plot mean growing season length was 130 days in Pinus sylvestris, 95 days in Larix decidua and 73 days in Picea abies supporting the hypothesis that early successional species are resource expenders, while late successional species are more efficient in utilizing resources and develop safer life strategies. High synchronicity found in culmination of radial growth in late spring (mid-May through early June) prior to occurrence of more favourable environmental conditions in summer might

  15. Photoprotection of evergreen and drought-deciduous tree leaves to overcome the dry season in monsoonal tropical dry forests in Thailand.

    Science.gov (United States)

    Ishida, Atsushi; Yamazaki, Jun-Ya; Harayama, Hisanori; Yazaki, Kenichi; Ladpala, Phanumard; Nakano, Takashi; Adachi, Minaco; Yoshimura, Kenichi; Panuthai, Samreong; Staporn, Duriya; Maeda, Takahisa; Maruta, Emiko; Diloksumpun, Sapit; Puangchit, Ladawan

    2014-01-01

    In tropical dry forests, uppermost-canopy leaves of evergreen trees possess the ability to use water more conservatively compared with drought-deciduous trees, which may result from significant differences in the photoprotective mechanisms between functional types. We examined the seasonal variations in leaf gas exchange, chlorophyll fluorescence and the amounts of photosynthetic pigments within lamina of the uppermost-canopy leaves of three drought-deciduous trees (Vitex peduncularis Wall., Xylia xylocarpa (Roxb.) W. Theob., Shorea siamensis Miq.), a semi-deciduous tree (Irvingia malayana Miq.) and two evergreen trees (Hopea ferrea Lanessan and Syzygium cumini (L.) Skeels) in Thailand. Area-based maximum carbon assimilation rates (Amax) decreased during the dry season, except in S. siamensis. The electron transport rate (ETR) remained unchanged in deciduous trees, but decreased during the dry season in evergreen and semi-deciduous trees. In the principal component analysis, the first axis (Axis 1) accounted for 44.3% of the total variation and distinguished deciduous from evergreen trees. Along Axis 1, evergreen trees were characterized by a high Stern-Volmer non-photochemical quenching coefficient (NPQ), high xanthophyll cycle pigments/chlorophyll and a high de-epoxidation state of the xanthophyll cycle, whereas the deciduous trees were characterized by a high ETR, a high quantum yield of PSII (ΦPSII = (Fm(') -F)/Fm(')) and a high mass-based Amax under high-light conditions. These findings indicate that drought-deciduous trees showing less conservative water use tend to dissipate a large proportion of electron flow through photosynthesis or alternative pathways. In contrast, the evergreens showed more conservative water use, reduced Amax and ETR and enhanced NPQ and xanthophyll cycle pigments/chlorophyll during the dry season, indicating that down-regulated photosynthesis with enhanced thermal dissipation of excess light energy played an important role in

  16. Temperature profiles from expendable bathythermograph (XBT) casts from the USCGC EVERGREEN in the North Atlantic Ocean in support of the Integrated Global Ocean Services System (IGOSS) from 09 November 1979 to 27 November 1979 (NODC Accession 8000180)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — XBT data were collected from the USCGC EVERGREEN in support of the Integrated Global Ocean Services System (IGOSS). Data were collected by the US Ships of...

  17. Temperature profiles from expendable bathythermograph (XBT) casts from the USCGC EVERGREEN in the East Coast - US/Canada in support of the Integrated Global Ocean Services System (IGOSS) project from 01 April 1978 to 21 April 1978 (NODC Accession 7800360)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — XBT data were collected from the USCGC EVERGREEN in support of the Integrated Global Ocean Services System (IGOSS) project. Data were collected by the US Coast Guard...

  18. Temperature profiles from expendable bathythermograph (XBT) casts from the USCGC EVERGREEN in the East Coast - US/Canada in support of the Integrated Global Ocean Services System (IGOSS) project from 16 February 1978 to 27 February 1978 (NODC Accession 7800196)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — XBT data were collected from the USCGC EVERGREEN in support of the Integrated Global Ocean Services System (IGOSS) project. Data were collected by the US Coast Guard...

  19. Temperature profiles from expendable bathythermograph (XBT) casts from the USCGC EVERGREEN in the North Atlantic Ocean in support of the Integrated Global Ocean Services System (IGOSS) from 23 January 1979 to 10 February 1979 (NODC Accession 7900115)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — XBT data were collected from the USCGC EVERGREEN in support of the Integrated Global Ocean Services System (IGOSS). Data were collected by the US Coast Guard from 23...

  20. Predicting vegetation type through physiological and environmental interactions with leaf traits: evergreen and deciduous forests in an earth system modeling framework.

    Science.gov (United States)

    Weng, Ensheng; Farrior, Caroline E; Dybzinski, Ray; Pacala, Stephen W

    2017-06-01

    Earth system models are incorporating plant trait diversity into their land components to better predict vegetation dynamics in a changing climate. However, extant plant trait distributions will not allow extrapolations to novel community assemblages in future climates, which will require a mechanistic understanding of the trade-offs that determine trait diversity. In this study, we show how physiological trade-offs involving leaf mass per unit area (LMA), leaf lifespan, leaf nitrogen, and leaf respiration may explain the distribution patterns of evergreen and deciduous trees in the temperate and boreal zones based on (1) an evolutionary analysis of a simple mathematical model and (2) simulation experiments of an individual-based dynamic vegetation model (i.e., LM3-PPA). The evolutionary analysis shows that these leaf traits set up a trade-off between carbon- and nitrogen-use efficiency at the scale of individual trees and therefore determine competitively dominant leaf strategies. As soil nitrogen availability increases, the dominant leaf strategy switches from one that is high in nitrogen-use efficiency to one that is high in carbon-use efficiency or, equivalently, from high-LMA/long-lived leaves (i.e., evergreen) to low-LMA/short-lived leaves (i.e., deciduous). In a region of intermediate soil nitrogen availability, the dominant leaf strategy may be either deciduous or evergreen depending on the initial conditions of plant trait abundance (i.e., founder controlled) due to feedbacks of leaf traits on soil nitrogen mineralization through litter quality. Simulated successional patterns by LM3-PPA from the leaf physiological trade-offs are consistent with observed successional dynamics of evergreen and deciduous forests at three sites spanning the temperate to boreal zones. © 2016 John Wiley & Sons Ltd.

  1. New forms of evergreening in Australia: misleading advertising, enantiomers and data exclusivity: Apotex v Servier and Alphapharm v Lundbeck.

    Science.gov (United States)

    Faunce, Thomas; Vines, Tim; Gibbons, Helen

    2008-10-01

    Two recent decisions of the Federal Court of Australia have provided interesting insights into the ongoing struggle between originator drug manufacturers and the public interest in Australia. In Apotex Pty Ltd (formerly GenRx Pty Ltd) v Les Laboratoires Servier (No 2) [2008] FCA 607 the court held that an advertising campaign by an originator pharmaceutical company, which sought to persuade doctors to issue prescriptions prohibiting substitution of "a-flagged" generics, constituted misleading and deceptive conduct under s 52 of the Trade Practices Act 1974 (Cth). The decision of the court in Alphapharm Pty Ltd v H Lundbeck A/S (2008) 76 IPR 618; [2008] FCA 559 limits the ability of the manufacturer of a drug based on a purified racemate enantiomer to claim a later registration date on the Australian Register of Therapeutic Goods and subsequently obtain an extension of its intellectual monopoly privileges as well as an exclusivity period for the data it had submitted to safety regulators. Importantly, this case is one of the first to consider recent allegedly pro- and anti-"evergreening" changes to the Therapeutic Goods Act 1989 (Cth) and Patents Act 1990 (Cth) as impacted by the intellectual property chapter (Ch 17) of the Australia-United States Free Trade Agreement.

  2. Fragmentation and management of Ethiopian moist evergreen forest drive compositional shifts of insect communities visiting wild Arabica coffee flowers.

    Science.gov (United States)

    Berecha, Gezahegn; Aerts, Raf; Muys, Bart; Honnay, Olivier

    2015-02-01

    Coffea arabica is an indigenous understorey shrub of the moist evergreen Afromontane forest of SW Ethiopia. Coffee cultivation here occurs under different forest management intensities, ranging from almost no intervention in the 'forest coffee' system to far-reaching interventions that include the removal of competing shrubs and selective thinning of the upper canopy in the 'semi-forest coffee' system. We investigated whether increasing forest management intensity and fragmentation result in impacts upon potential coffee pollination services through examining shifts in insect communities that visit coffee flowers. Overall, we netted 2,976 insect individuals on C. arabica flowers, belonging to sixteen taxonomic groups, comprising 10 insect orders. Taxonomic richness of the flower-visiting insects significantly decreased and pollinator community changed with increasing forest management intensity and fragmentation. The relative abundance of honey bees significantly increased with increasing forest management intensity and fragmentation, likely resulting from the introduction of bee hives in the most intensively managed forests. The impoverishment of the insect communities through increased forest management intensity and fragmentation potentially decreases the resilience of the coffee production system as pollination increasingly relies on honey bees alone. This may negatively affect coffee productivity in the long term as global pollination services by managed honey bees are expected to decline under current climate change scenarios. Coffee agroforestry management practices should urgently integrate pollinator conservation measures.

  3. Snow damage strongly reduces the strength of the carbon sink in a primary subtropical evergreen broadleaved forest

    Science.gov (United States)

    Song, Qing-Hai; Fei, Xue-Hai; Zhang, Yi-Ping; Sha, Li-Qing; Wu, Chuan-Sheng; Lu, Zhi-Yun; Luo, Kang; Zhou, Wen-Jun; Liu, Yun-Tong; Gao, Jin-Bo

    2017-10-01

    A primary subtropical evergreen broadleaved forest in southwest China experienced a particularly extreme snowfall event during January 2015. The 2015 event enabled the quantification of the impact of the extreme meteorological event on the forest carbon balance. We analyzed five years of continuous measurements of CO2 exchange across the biosphere/atmosphere interface in the forest using an eddy covariance technique. We quantified how exposure to an extreme meteorological event affected ecosystem processes that determine gross primary productivity (GPP) and ecosystem respiration (R eco), and thus annual net carbon (C) sequestration. The forest canopy was severely damaged by the heavy snow, and the leaf area index (LAI) decreased significantly from January to July 2015. GPP, net ecosystem exchange (NEE), and R eco all sharply decreased in 2015 after the heavy snow. On average, a strong decrease of 544 g C m‑2 year‑1 in annual NEE in 2015 was associated with a decrease of 829 g C m‑2 year‑1 in annual GPP and a decrease of 285 g C m‑2 year‑1 in annual R eco. Overall, annual net C uptake in 2015 was reduced by 76% compared to the mean C uptake of the previous four years. A sharp increase in carbon uptake was also observed in 2016, indicating that long-term, continuous measurements should be carried out to evaluate the overall response to the disturbance.

  4. Fragmentation and Management of Ethiopian Moist Evergreen Forest Drive Compositional Shifts of Insect Communities Visiting Wild Arabica Coffee Flowers

    Science.gov (United States)

    Berecha, Gezahegn; Aerts, Raf; Muys, Bart; Honnay, Olivier

    2015-02-01

    Coffea arabica is an indigenous understorey shrub of the moist evergreen Afromontane forest of SW Ethiopia. Coffee cultivation here occurs under different forest management intensities, ranging from almost no intervention in the `forest coffee' system to far-reaching interventions that include the removal of competing shrubs and selective thinning of the upper canopy in the `semi-forest coffee' system. We investigated whether increasing forest management intensity and fragmentation result in impacts upon potential coffee pollination services through examining shifts in insect communities that visit coffee flowers. Overall, we netted 2,976 insect individuals on C. arabica flowers, belonging to sixteen taxonomic groups, comprising 10 insect orders. Taxonomic richness of the flower-visiting insects significantly decreased and pollinator community changed with increasing forest management intensity and fragmentation. The relative abundance of honey bees significantly increased with increasing forest management intensity and fragmentation, likely resulting from the introduction of bee hives in the most intensively managed forests. The impoverishment of the insect communities through increased forest management intensity and fragmentation potentially decreases the resilience of the coffee production system as pollination increasingly relies on honey bees alone. This may negatively affect coffee productivity in the long term as global pollination services by managed honey bees are expected to decline under current climate change scenarios. Coffee agroforestry management practices should urgently integrate pollinator conservation measures.

  5. Can native plant species be preserved in an anthropogenic forest landscape dominated by aliens? A case study from Mediterranean Chile

    Directory of Open Access Journals (Sweden)

    Steffi Heinrichs

    2016-06-01

    Full Text Available Plantations with fast growing exotic tree species can negatively affect native plant species diversity and promote the spread of alien species. Mediterranean Chile experienced major landscape changes with a vast expansion of industrial plantations of Pinus radiata in the past. However, with increasing knowledge of biodiversity effects on ecosystem services Chilean forest owners now aim to integrate the conservation of native biodiversity into forest management, but data on native species diversity and establishment within a plantation landscape is scarce. Here we investigated plant species diversity and composition in four forest management options applied within a landscape dominated by P. radiata plantations in comparison to an unmanaged reference: (i a clear cut, (ii a strip cut, (iii a native canopy of Nothofagus glauca and (iv a young P. radiata plantation. We wanted to assess if native plant species can be maintained either by natural regeneration or by planting of native tree species (Nothofagus glauca, N. obliqua, Quillaja saponaria within this landscape. Results show a high diversity of native and forest plant species within the different management options indicating a high potential for native biodiversity restoration within an anthropogenic landscape. In particular, herbaceous species can benefit from management. They are rare in unmanaged natural forests that are characterized by low light conditions and a thick litter layer. Management, however, also promoted a diversity of alien species. The rapid spread of alien grass species after management can deter an initial establishment of native tree species or the survival and growth after planting mainly under dry but less under sufficient moisture conditions. The most unsuccessful option for promoting native plant species was clear cutting in a dry area where alien grasses were abundant. For drought-tolerant tree species such as Quillaja saponaria, though

  6. Dispersal limitation at the expanding range margin of an evergreen tree in urban habitats?

    DEFF Research Database (Denmark)

    Møller, Linda Agerbo; Skou, Anne-Marie Thonning; Kollmann, Johannes Christian

    2012-01-01

    Dispersal limitations contribute to shaping plant distribution patterns and thus are significant for biodiversity conservation and urban ecology. In fleshy-fruited plants, for example, any preference of frugivorous birds affects dispersal capacities of certain fruit species. We conducted a removal...... cultivars were offered to birds at the expanding range margin in urban habitats in eastern Denmark. The four fruit types were removed at different rates and red fruits were preferred over a yellow cultivar. Small fruit diameter was positively related to fruit removal, and removal was faster under tree...... canopies compared with open habitats. The preference for red cultivars compared with native I. aquifolium may contribute to naturalization and potential invasion of garden escapes. Preferential foraging under closed canopies indicates trees and shrubs as recruitment foci for fleshy-fruited plants in urban...

  7. Adiantum shastense, a new species of maidenhair fern from California

    Directory of Open Access Journals (Sweden)

    Layne Huiet

    2015-07-01

    Full Text Available A new species of Adiantum is described from California. This species is endemic to northern California and is currently known only from Shasta County. We describe its discovery after first being collected over a century ago and distinguish it from A. jordanii and A. capillus-veneris. It is evergreen and is sometimes, but not always, associated with limestone. The range of Adiantum shastense Huiet & A.R.Sm., sp. nov., is similar to several other Shasta County endemics that occur in the mesic forests of the Eastern Klamath Range, close to Shasta Lake, on limestone and metasedimentary substrates.

  8. Seasonal ozone uptake by a warm-temperate mixed deciduous and evergreen broadleaf forest in western Japan estimated by the Penman-Monteith approach combined with a photosynthesis-dependent stomatal model.

    Science.gov (United States)

    Kitao, Mitsutoshi; Komatsu, Masabumi; Hoshika, Yasutomo; Yazaki, Kenichi; Yoshimura, Kenichi; Fujii, Saori; Miyama, Takafumi; Kominami, Yuji

    2014-01-01

    Canopy-level stomatal conductance over a warm-temperate mixed deciduous and evergreen broadleaf forest in Japan was estimated by the Penman-Monteith approach, as compensated by a semi-empirical photosynthesis-dependent stomatal model, where photosynthesis, relative humidity, and CO2 concentration were assumed to regulate stomatal conductance. This approach, using eddy covariance data and routine meteorological observations at a flux tower site, permits the continuous estimation of canopy-level O3 uptake, even when the Penman-Monteith approach is unavailable (i.e. in case of direct evaporation from soil or wet leaves). Distortion was observed between the AOT40 exposure index and O3 uptake through stomata, as AOT40 peaked in April, but with O3 uptake occurring in July. Thus, leaf pre-maturation in the predominant deciduous broadleaf tree species (Quercus serrata) might suppress O3 uptake in springtime, even when the highest O3 concentrations were observed. Copyright © 2013 Elsevier Ltd. All rights reserved.

  9. Seasonal dynamics in the stable carbon isotope composition δ¹³C from non-leafy branch, trunk and coarse root CO₂ efflux of adult deciduous (Fagus sylvatica) and evergreen (Picea abies) trees.

    Science.gov (United States)

    Kuptz, Daniel; Matyssek, Rainer; Grams, Thorsten E E

    2011-03-01

    Respiration is a substantial driver of carbon (C) flux in forest ecosystems and stable C isotopes provide an excellent tool for its investigation. We studied seasonal dynamics in δ¹³C of CO₂ efflux (δ¹³C(E)) from non-leafy branches, upper and lower trunks and coarse roots of adult trees, comparing deciduous Fagus sylvatica (European beech) with evergreen Picea abies (Norway spruce). In both species, we observed strong and similar seasonal dynamics in the δ¹³C(E) of above-ground plant components, whereas δ¹³C(E) of coarse roots was rather stable. During summer, δ¹³C(E) of trunks was about -28.2‰ (Beech) and -26.8‰ (Spruce). During winter dormancy, δ¹³C(E) increased by 5.6-9.1‰. The observed dynamics are likely related to a switch from growth to starch accumulation during fall and remobilization of starch, low TCA cycle activity and accumulation of malate by PEPc during winter. The seasonal δ¹³C(E) pattern of branches of Beech and upper trunks of Spruce was less variable, probably because these organs were additionally supplied by winter photosynthesis. In view of our results and pervious studies, we conclude that the pronounced increases in δ¹³C(E) of trunks during the winter results from interrupted access to recent photosynthates. © 2010 Blackwell Publishing Ltd.

  10. Faunal diversity in a semi-evergreen forest of Bornadi-Khalingduar Complex of Assam, India

    Directory of Open Access Journals (Sweden)

    Pallabi Chakraborty

    2015-09-01

    Full Text Available The Bornadi-Khalingduar Complex under the Manas Tiger Reserve, Assam is known to be an important area for wildlife movement to and from India and Bhutan. The contiguous landscape encompassing the two neighbouring countries provides a good habitat for diversity of wildlife and also as an important corridor area.  We carried out an opportunistic camera-trapping exercise to document the faunal diversity in the area. A month-long exercise photo-captured a total of 19 species belonging to 12 families, including the Leopard, Wild Dog, Leopard Cat, Binturong, Elephant, Sambar, Barking Deer and various birds. These findings of the study reveal the importance, threats and potential of the area and recommendations have been made to secure this corridor for continuous animal movement. Anthropogenic disturbance is a major deterrent to undisturbed animal movement in this area with resultant forest fragmentation and degradation. This indicates the need for effective conservation strategies in order to maintain the remnants of this corridor complex.  

  11. First identification of the pathogen causing tumor malformations in evergreen oaks in Spain

    Directory of Open Access Journals (Sweden)

    María Martín-Santafé

    2014-08-01

    Full Text Available Aim of study: In recent years an increase in pests and diseases associated with truffle plantations has been detected in Spain. The appearance of tumor malformations in trunks and branches of Quercus ilex L. must be highlighted. These bumps have expanded dramatically since the increase in the number and density of truffle plantations. This pathology is not only found in plantations, but also in forests, and in trees of all ages.Area of study: the eastern mountains and the truffle plantations of the Iberian Peninsula.Material and methods: Positive results were obtained by using two types of PCR: Real-Time PCR and nested-PCR. They were carried out with primers that amplified 16S ribosomal gene sequences that are common to all known phytoplasmas.Main result: The disease manifests itself as an irregular thickening in branches of any age and in the trunk that results in the woody tissue cracking open, forming wounds. The affected branches usually undergo necrosis and in case of affecting the trunk, the tree will eventually die. After an extensive literature review and several failed attempts to isolate fungal and bacterial species from these tumors and wounds, the disease-causing organism has been identified as a Candidatus Phytoplasma.Research highlights: The appearance of this disease may endanger the profitability of an a priori profitable crop. Due to the intrinsic characteristics of the organism, and knowing that no phytosanitary treatment is able to control phytoplasmas, future works should be directed towards identifying the transmitter in order to control the disease.Key words: Candidatus Phytoplasma; PCR; Quercus ilex; black truffle; Tuber melanosporum.

  12. Drought reduced monoterpene emissions from the evergreen Mediterranean oak Quercus ilex: results from a throughfall displacement experiment

    Directory of Open Access Journals (Sweden)

    S. Rambal

    2009-07-01

    Full Text Available The effects of water limitations on the emission of biogenic volatile organic compounds are not well understood. Experimental approaches studying drought effects in natural conditions are still missing. To address this question, a throughfall displacement experiment was set up in a natural forest of Quercus ilex, an evergreen Mediterranean oak emitting monoterpenes. Mature trees were exposed in 2005 and 2006 either to an additional drought, to irrigation or to natural drought (untreated control. In both years, absolute monoterpene emission rates as well as the respective standard factors of the trees exposed to normal and additional drought strongly declined during the drought periods. Monoterpene emissions were lower in year 2006 than in year 2005 (factor 2 due to a more pronounced summer drought period in this respective year. We observed a significant difference between the irrigation and additional drought or control treatment: irrigated trees emitted 82% more monoterpenes during the drought period 2006 than the trees of the other treatments. However, no significant effect on monoterpene emission was observed between normal and additional drought treatments, despite a significant effect on leaf water potential and photochemical efficiency. During the development of drought, monoterpene emissions responded exponentially rather than linearly to decreasing leaf water potential. Emissions rapidly declined when the water potential dropped below −2 MPa and photosynthesis was persistently inhibited. Monoterpene synthase activities measured in vitro showed no clear reduction during the same period. From our results we conclude that drought significantly reduces monoterpene fluxes of Mediterranean Holm oak forest into the atmosphere due to a lack of primary substrates coming from photosynthetic processes.

  13. Chemistry is Evergreen

    Indian Academy of Sciences (India)

    Home; Journals; Resonance – Journal of Science Education; Volume 14; Issue 3. Chemistry is Everygreen - 2008 Nobel Prize in Chemistry. Swagata Dasgupta. General Article Volume 14 Issue 3 March 2009 pp 248-258. Fulltext. Click here to view fulltext PDF. Permanent link:

  14. Phyto climatic characterization and cartography of sub antarctic native forests in Isla Grande de Tierra del Fuego (Patagonia, Argentina); Caracterizacion y cartografia fitoclimaticas del bosque nativo subantartico en la Isla Grande de Tierra del Fuego (Patagonia, Argentina)

    Energy Technology Data Exchange (ETDEWEB)

    Allue, C.; Arranz, J. A.; Bava, J. O.; Beneitez, J. M.; Collado, L.; Garcia-Lopez, J. M.

    2010-07-01

    Isla Grande de Tierra del Fuego is especially peculiar in phytoclimatic terms, situated as it is at an extreme southerly latitude, surrounded by large water masses and close to the great mass of Antarctic ice. Its main peculiarities in this sense are the coolness of its summers and a very narrow temperature range. As a result, the woodland landscapes in the parts with forest cover are dominated by microphyllous broadleaf physiognomies, both evergreen and deciduous, of the Nothofagus genus. This paper reports a more in-depth investigation of the hitherto little-known phytoclimatic conditions in that territory which included calibration and validation of a model of phytoclimatic suitability that addresses the principal plant physiognomic units and phytoclimatic mapping. It discusses the causes behind the presence of broadleaf formations in thermal conditions which in the northern hemisphere would allow only coniferous formations or no tree formations at all, and also the edaphic peculiarities that may explain the presence of a evergreen species like Nothofagus betuloides in subantarctic mixed forests. (Author) 111 refs.

  15. Eco-physiological adaptation of dominant tree species at two contrasting karst habitats in southwestern China [v2; ref status: indexed, http://f1000r.es/2d9

    Directory of Open Access Journals (Sweden)

    Shouren Zhang

    2013-11-01

    Full Text Available The purpose of this study was to investigate the eco-physiological adaptation of indigenous woody species to their habitats in karst areas of southwestern China. Two contrasting forest habitats were studied: a degraded habitat in Daxiagu and a well-developed habitat in Tianlongshan, and the eco-physiological characteristics of the trees were measured for three growth seasons. Photosynthetic rate (Pn, stomatal conductance (gs, and transpiration rate (Tr of the tree species in Daxiagu were 2-3 times higher than those in Tianlongshan under ambient conditions. However, this habitat effect was not significant when measurements were taken under controlled conditions. Under controlled conditions, Pn, gs, and Tr of the deciduous species were markedly higher than those for the evergreen species. Habitat had no significant effect on water use efficiency (WUE or photochemical characteristics of PSII. The stomatal sensitivity of woody species in the degraded habitat was much higher than that in the well-developed habitat. Similarly, the leaf total nitrogen (N and phosphorus (P contents expressed on the basis of either dry mass or leaf area were also much higher in Daxiagu than they were in Tianlongshan. The mass-based leaf total N content of deciduous species was much higher than that of evergreen species, while leaf area-based total N and P contents of evergreens were significantly higher than those of deciduous species. The photosynthetic nitrogen- and phosphorus-use efficiencies (PNUE and PPUE of deciduous species were much higher than those of evergreens. Further, the PPUE of the woody species in Tianlongshan was much higher than that  of the woody species in Daxiagu. The results from three growth seasons imply that the tree species were able to adapt well to their growth habitats. Furthermore, it seems that so-called “temporary drought stress” may not occur, or may not be severe for most woody plants in karst areas of southwestern China.

  16. Radiocesium contaminations of 20 wood species and the corresponding gamma-ray dose rates around the canopies at 5 months after the Fukushima nuclear power plant accident.

    Science.gov (United States)

    Yoshihara, Toshihiro; Matsumura, Hideyuki; Hashida, Shin-nosuke; Nagaoka, Toru

    2013-01-01

    Radiocesium ((134)Cs + (137)Cs) deposition from the Fukushima nuclear power plant accident was measured in 20 woody plants (12 evergreen and 8 deciduous species) grown in Abiko (approximately 200 km SSW from the NPP). Leaves (needles) and twigs were sampled from each of three foliar positions (top, middle, and bottom) in the plant canopy in early August 2011. At the time, soils around the plants were also sampled, and gamma radiation dose rates were measured at each sampling position. The average radiocesium activity in the observed leaves of the evergreen species was 7.7 times that in the leaves of the deciduous species. Among the observed evergreen coniferous species, the activity in pre-fallout-expanded leaves was 2.4 times that in the post-fallout-expanded leaves. Notably, a distinct variation in the activity among the evergreen coniferous species could be observed for the post-fallout-expanded leaves but not for the pre-fallout-expanded leaves. Although these differences depend on whether the leaves had expanded at the time of the fallout, it is probable that a considerable amount of radiocesium was translocated to newly developed leaves at a species-specific rate. In addition, it was demonstrated that dose rates around woody plants were not consistent with the prevailing prediction that general dose rates correspondingly decrease with monitoring height from the ground. Thus, the dose rates in the top foliar layer of the deciduous species decreased more than predicted, whereas those in the top foliar layer of the coniferous species did not decrease. This may be due to differences in the balance between the attenuation resulting from a shielding effect of the plant bodies and the higher radiocesium accumulation in the leaves. Copyright © 2012 Elsevier Ltd. All rights reserved.

  17. Rapid forest clearing in a Myanmar proposed national park threatens two newly discovered species of geckos (Gekkonidae: Cyrtodactylus)

    Science.gov (United States)

    Oswald, Patrick; Thura, Myint Kyaw; LaJeunesse Connette, Katherine J.; Grindley, Mark E.; Songer, Melissa; Zug, George R.; Mulcahy, Daniel G.

    2017-01-01

    Myanmar’s recent transition from military rule towards a more democratic government has largely ended decades of political and economic isolation. Although Myanmar remains heavily forested, increased development in recent years has been accompanied by exceptionally high rates of forest loss. In this study, we document the rapid progression of deforestation in and around the proposed Lenya National Park, which includes some of the largest remaining areas of lowland evergreen rainforest in mainland Southeast Asia. The globally unique forests in this area are rich in biodiversity and remain a critical stronghold for many threatened and endangered species, including large charismatic fauna such as tiger and Asian elephant. We also conducted a rapid assessment survey of the herpetofauna of the proposed national park, which resulted in the discovery of two new species of bent-toed geckos, genus Cyrtodactylus. We describe these new species, C. lenya sp. nov. and C. payarhtanensis sp. nov., which were found in association with karst (i.e., limestone) rock formations within mature lowland wet evergreen forest. The two species were discovered less than 35 km apart and are each known from only a single locality. Because of the isolated nature of the karst formations in the proposed Lenya National Park, these geckos likely have geographical ranges restricted to the proposed protected area and are threatened by approaching deforestation. Although lowland evergreen rainforest has vanished from most of continental Southeast Asia, Myanmar can still take decisive action to preserve one of the most biodiverse places on Earth. PMID:28403189

  18. Rapid forest clearing in a Myanmar proposed national park threatens two newly discovered species of geckos (Gekkonidae: Cyrtodactylus.

    Directory of Open Access Journals (Sweden)

    Grant M Connette

    Full Text Available Myanmar's recent transition from military rule towards a more democratic government has largely ended decades of political and economic isolation. Although Myanmar remains heavily forested, increased development in recent years has been accompanied by exceptionally high rates of forest loss. In this study, we document the rapid progression of deforestation in and around the proposed Lenya National Park, which includes some of the largest remaining areas of lowland evergreen rainforest in mainland Southeast Asia. The globally unique forests in this area are rich in biodiversity and remain a critical stronghold for many threatened and endangered species, including large charismatic fauna such as tiger and Asian elephant. We also conducted a rapid assessment survey of the herpetofauna of the proposed national park, which resulted in the discovery of two new species of bent-toed geckos, genus Cyrtodactylus. We describe these new species, C. lenya sp. nov. and C. payarhtanensis sp. nov., which were found in association with karst (i.e., limestone rock formations within mature lowland wet evergreen forest. The two species were discovered less than 35 km apart and are each known from only a single locality. Because of the isolated nature of the karst formations in the proposed Lenya National Park, these geckos likely have geographical ranges restricted to the proposed protected area and are threatened by approaching deforestation. Although lowland evergreen rainforest has vanished from most of continental Southeast Asia, Myanmar can still take decisive action to preserve one of the most biodiverse places on Earth.

  19. Rapid forest clearing in a Myanmar proposed national park threatens two newly discovered species of geckos (Gekkonidae: Cyrtodactylus).

    Science.gov (United States)

    Connette, Grant M; Oswald, Patrick; Thura, Myint Kyaw; LaJeunesse Connette, Katherine J; Grindley, Mark E; Songer, Melissa; Zug, George R; Mulcahy, Daniel G

    2017-01-01

    Myanmar's recent transition from military rule towards a more democratic government has largely ended decades of political and economic isolation. Although Myanmar remains heavily forested, increased development in recent years has been accompanied by exceptionally high rates of forest loss. In this study, we document the rapid progression of deforestation in and around the proposed Lenya National Park, which includes some of the largest remaining areas of lowland evergreen rainforest in mainland Southeast Asia. The globally unique forests in this area are rich in biodiversity and remain a critical stronghold for many threatened and endangered species, including large charismatic fauna such as tiger and Asian elephant. We also conducted a rapid assessment survey of the herpetofauna of the proposed national park, which resulted in the discovery of two new species of bent-toed geckos, genus Cyrtodactylus. We describe these new species, C. lenya sp. nov. and C. payarhtanensis sp. nov., which were found in association with karst (i.e., limestone) rock formations within mature lowland wet evergreen forest. The two species were discovered less than 35 km apart and are each known from only a single locality. Because of the isolated nature of the karst formations in the proposed Lenya National Park, these geckos likely have geographical ranges restricted to the proposed protected area and are threatened by approaching deforestation. Although lowland evergreen rainforest has vanished from most of continental Southeast Asia, Myanmar can still take decisive action to preserve one of the most biodiverse places on Earth.

  20. Greater diversity of soil fungal communities and distinguishable seasonal variation in temperate deciduous forests compared with subtropical evergreen forests of eastern China.

    Science.gov (United States)

    He, Jinhong; Tedersoo, Leho; Hu, Ang; Han, Conghai; He, Dan; Wei, Hui; Jiao, Min; Anslan, Sten; Nie, Yanxia; Jia, Yongxia; Zhang, Gengxin; Yu, Guirui; Liu, Shirong; Shen, Weijun

    2017-07-01

    Whether and how seasonality of environmental variables impacts the spatial variability of soil fungal communities remain poorly understood. We assessed soil fungal diversity and community composition of five Chinese zonal forests along a latitudinal gradient spanning 23°N to 42°N in three seasons to address these questions. We found that soil fungal diversity increased linearly or parabolically with latitude. The seasonal variations in fungal diversity were more distinguishable in three temperate deciduous forests than in two subtropical evergreen forests. Soil fungal diversity was mainly correlated with edaphic factors such as pH and nutrient contents. Both latitude and its interactions with season also imposed significant impacts on soil fungal community composition (FCC), but the effects of latitude were stronger than those of season. Vegetational properties such as plant diversity and forest age were the dominant factors affecting FCC in the subtropical evergreen forests while edaphic properties were the dominant ones in the temperate deciduous forests. Our results indicate that latitudinal variation patterns of soil fungal diversity and FCC may differ among seasons. The stronger effect of latitude relative to that of season suggests a more important influence by the spatial than temporal heterogeneity in shaping soil fungal communities across zonal forests. © FEMS 2017. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  1. [A comparative study on soil fauna in native secondary evergreen broad-leaved forest and Chinese fir plantation forests in subtropics].

    Science.gov (United States)

    Yan, Shaokui; Wang, Silong; Hu, Yalin; Gao, Hong; Zhang, Xiuyong

    2004-10-01

    In this study, we investigated the response of soil animal communities to the replacement of native secondary forest by Chinese fir plantation forest and successive rotation of Chinese fir in subtropics. Three adjacent forest stands, i.e., native secondary evergreen broad-leaved forest stand (control) and Chinese fir plantation stands of first (20 yr) and second (20 yr) rotations were selected for the comparison of soil fauna. All animals were extracted from the floor litter and 0-15 cm soil layer of the stands in Summer, 2003 by using Tullgren method, wet funnel method and hand-sorting method. Compared to two Chinese fir plantation forests, the native secondary evergreen broad-leaved forest had a higher abundance and a higher taxonomic diversity of animals in soil and litter, but there were no significant differences in the biomass and productivity of soil fauna between all study stands. The abundance or diversity did not differ significantly between the first rotation and second rotation stands, too. The results supported that vegetation cover might be one of the main forces driving the development of soil animal communities, and the effect of successive rotation of Chinese fir on the development of soil fauna was a slow-running process.

  2. POLLINATION ECOLOGY OF TARENNA ASIATICA (L.) KUNTZ EX. K. SCHUM. (RUBIACEAE), A KEYSTONE EVERGREEN SHRUB SPECIES IN THE EASTERN GHATS FOREST - ANDHRA PRADESH, INDIA

    OpenAIRE

    A. Jacob Solomon Raju; M. Mallikarjuna Rao

    2016-01-01

    Tarenna asiatica flowers throughout the year with profuse flowering during december-april. the flowers are hermaphroditic, self- and cross-compatible, protandrous, nectariferous and entomophilous. the mating system is facultatively xenogamous with highest fruit set in xenogamy. The protandry facilitates autonomous selfing. Bees and butterflies effect both self- and cross-pollinations. Fruits mature within a short period and the fallen seeds germinate following monsoon rains in June-July. a de...

  3. Identifying the best season for mapping evergreen swamp and mangrove species using leaf-level spectra in an estuarine system in KwaZulu-Natal, South Africa

    CSIR Research Space (South Africa)

    Van Deventer, Heidi

    2014-10-01

    Full Text Available Swamp and mangrove forests are some of the most threatened forest types in the world. In Africa, these forests are essential in providing food, construction material and medicine to people. These forest types have not sufficiently been mapped...

  4. Monitoring phenology of photosynthesis in temperate evergreen and mixed deciduous forests using the normalized difference vegetation index (NDVI) and the photochemical reflectance index (PRI) at leaf and canopy scales

    Science.gov (United States)

    Wong, C. Y.; Arain, M. A.; Ensminger, I.

    2016-12-01

    Evergreen conifers in boreal and temperate regions undergo strong seasonal changes in photoperiod and temperatures, which determines their phenology of high photosynthetic activity in the growing season and downregulation during the winter. Monitoring the timing of the transition between summer activity and winter downregulation in evergreens is difficult since this is a largely invisible process, unlike in deciduous trees that have a visible budding and a sequence of leaf unfolding in the spring and leaf abscission in the fall. The light-use efficiency (LUE) model estimates gross primary productivity (GPP) and may be parameterized using remotely sensed vegetation indices. Using spectral reflectance data, we derived the normalized difference vegetation index (NDVI), a measure of leaf "greenness", and the photochemical reflectance index (PRI), a proxy for chlorophyll:carotenoid ratios which is related to photosynthetic activity. To better understand the relationship between these vegetation indices and photosynthetic activity and to contrast this relationship between plant functional types, the phenology of NDVI, PRI and photosynthesis was monitored in an evergreen forest and a mixed deciduous forest at the leaf and canopy scale. Our data indicates that the LUE model can be parameterized by NDVI and PRI to track forest phenology. Differences in the sensitivity of PRI and NDVI will be discussed. These findings have implications to address the phenology of evergreen conifers by using PRI to complement NDVI in the LUE model, potentially improving model productivity estimates in northern hemisphere forests, that are dominated by conifers.

  5. Presence of understory shrubs constrains carbon gain in sunflecks by advance-regeneration seedlings: evidence from Quercus Rubra seedling grouwing in understory forest patches with or without evergreen shrubs present

    Science.gov (United States)

    E.T. Nilsen; T.T. Lei; S.W. Semones

    2009-01-01

    We investigated whether dynamic photosynthesis of understory Quercus rubra L. (Fagaceae) seedlings can acclimate to the altered pattern of sunflecks in forest patches with Rhododendron maximum L. (Ericaceae), an understory evergreen shrub. Maximum photosynthesis (A) and total CO2 accumulated during lightflecks was greatest for 400-s lightflecks, intermediate for 150-s...

  6. Phytochemistry and Pharmacology of Berberis Species

    Science.gov (United States)

    Mokhber-Dezfuli, Najmeh; Saeidnia, Soodabeh; Gohari, Ahmad Reza; Kurepaz-Mahmoodabadi, Mahdieh

    2014-01-01

    The genus Berberis (Berberidaceae) includes about 500 species worldwide, some of which are widely cultivated in the north-eastern regions of Iran. This genus consists of spiny deciduous evergreen shrubs, characterized by yellow wood and flowers. The cultivation of seedless barberry in South Khorasan goes back to two hundred years ago. Medicinal properties for all parts of these plants have been reported, including: Antimicrobial, antiemetic, antipyretic, antioxidant, anti-inflammatory, anti-arrhythmic, sedative, anti-cholinergic, cholagogic, anti-leishmaniasis, and anti-malaria. The main compounds found in various species of Berberis, are berberine and berbamine. Phytochemical analysis of various species of this genus revealed the presence of alkaloids, tannins, phenolic compounds, sterols and triterpenes. Although there are some review articles on Berberis vulgaris (as the most applied species), there is no review on the phytochemical and pharmacological activities of other well-known species of the genus Berberis. For this reason, the present review mainly focused on the diverse secondary metabolites of various species of this genus and the considerable pharmacological and biological activities together with a concise story of the botany and cultivation. PMID:24600191

  7. The Evergreen basin and the role of the Silver Creek fault in the San Andreas fault system, San Francisco Bay region, California

    Science.gov (United States)

    Jachens, Robert C.; Wentworth, Carl M.; Graymer, Russell W.; Williams, Robert; Ponce, David A.; Mankinen, Edward A.; Stephenson, William J.; Langenheim, Victoria

    2017-01-01

    The Evergreen basin is a 40-km-long, 8-km-wide Cenozoic sedimentary basin that lies mostly concealed beneath the northeastern margin of the Santa Clara Valley near the south end of San Francisco Bay (California, USA). The basin is bounded on the northeast by the strike-slip Hayward fault and an approximately parallel subsurface fault that is structurally overlain by a set of west-verging reverse-oblique faults which form the present-day southeastward extension of the Hayward fault. It is bounded on the southwest by the Silver Creek fault, a largely dormant or abandoned fault that splays from the active southern Calaveras fault. We propose that the Evergreen basin formed as a strike-slip pull-apart basin in the right step from the Silver Creek fault to the Hayward fault during a time when the Silver Creek fault served as a segment of the main route by which slip was transferred from the central California San Andreas fault to the Hayward and other East Bay faults. The dimensions and shape of the Evergreen basin, together with palinspastic reconstructions of geologic and geophysical features surrounding it, suggest that during its lifetime, the Silver Creek fault transferred a significant portion of the ∼100 km of total offset accommodated by the Hayward fault, and of the 175 km of total San Andreas system offset thought to have been accommodated by the entire East Bay fault system. As shown previously, at ca. 1.5–2.5 Ma the Hayward-Calaveras connection changed from a right-step, releasing regime to a left-step, restraining regime, with the consequent effective abandonment of the Silver Creek fault. This reorganization was, perhaps, preceded by development of the previously proposed basin-bisecting Mount Misery fault, a fault that directly linked the southern end of the Hayward fault with the southern Calaveras fault during extinction of pull-apart activity. Historic seismicity indicates that slip below a depth of 5 km is mostly transferred from the Calaveras

  8. NATURAL VEGETATION AND ECOSYSTEM SERVICES RELATED TO AIR QUALITY IMPROVEMENT: TROPOSPHERIC OZONE REMOVAL BY EVERGREEN AND DECIDUOUS FORESTS IN LATIUM (ITALY

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    F. Manes

    2012-06-01

    Full Text Available The background concentrations of tropospheric ozone (O3 are increasing in both industrialized and developing countries, thus posing a concrete risk to human health, natural vegetation and crops. Several papers have reported that the total O3 flux from the atmosphere to canopy surfaces can have positive effects on air quality, and consequently to human health and wellbeing. In this work, we have estimated the role of the main natural woody vegetation classes of the CORINE Land cover Classification System in the Latium Region (Central Italy in removing O3 during the growing season of the year 2005. Cumulated O3 fluxes data allowed to estimate the externality value of this ecosystem service provided by deciduous and evergreen forests in the Latium region to be around a total value of 85025821.  In the Apennine chain Province, this value should be around 57248431 $ while  in the Tyrrhenian Borderland Province 2286567 $, 22376136 $ and 3114686 $ for deciduous and evergreen forests, respectively. This corresponds, for the growing season 2005, to a total value of 85025821 $ attributable to the ecosystem service of tropospheric O3 removal provided by the natural forests of the Latium region. Although we acknowledge the uncertainty in producing such estimate, we think our effort  as a useful first contribution addressed to the monetization of one of the ecosystem services of Italian forests at a regional level, and more in general, to open the discussion in a field that would be very useful in forest management and environmental policy-making. 

  9. Regionalización biogeográfica de la mastofauna de los bosques tropicales perennifolios de Mesoamérica Biogeographic regionalization of the mammals of tropical evergreen forests in Mesoamerica

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    Héctor C. Olguín-Monroy

    2013-06-01

    Full Text Available Este trabajo presenta una propuesta de regionalización biogeográfica de los bosques tropicales perennifolios de Mesoamérica, resultado de un análisis de parsimonia de endemismos (PAE, utilizando modelos de nicho ecológico (GARP con mamíferos terrestres, usando 41 527 registros para las 233 especies de mamíferos reconocidas. La regionalización propuesta muestra que los bosques tropicales perennifolios de Mesoamérica se dividen por el istmo de Tehuantepec en Oaxaca en: a un grupo septentrional que comprende la Sierra Madre de Chiapas-Guatemala y la Península de Yucatán, y b un grupo austral, que contiene la vertiente pacífica hacia el sur incluyendo Centroamérica. Además se encontró congruencia con trabajos filogenéticos, lo que sugiere una historia biogeográfica común.Mesoamerica is a biologically complex zone that expands from Southern Mexico to extreme Northern Colombia. The biogeographical patterns and relationships of the mammalian fauna associated to the Mesoamerican Tropical Evergreen Forest (MTEF are poorly understood, in spite of the wide distribution of this kind of habitat in the region. We compiled a complete georeferenced database of mammalian species distributed in the MTEF of specimens from museum collections and scientific literature. This database was used to create potential distribution maps through the use of environmental niche models (ENMs by using the Genetic Algorithm for Rule-Set Production (GARP using 22 climatic and topographic layers. Each map was used as a representation of the geographic distribution of the species and all available maps were summed to obtain general patterns of species richness in the region. Also, the maps were used to construct a presence-absence matrix in a grid of squares of 0.5 degrees of side, that was analyzed in a Parsimony Analysis of Endemicity (PAE, which resulted in a hypothesis of the biogeographic scheme in the region. We compiled a total of 41 527 records of 233

  10. Winter variation in physiological status of cold stored and freshly lifted semi-evergreen quercus nigra seedlings

    Science.gov (United States)

    Rosa C. Goodman; Douglass F. Jacobs; Kent G. Apostol; Barrett C. Wilson; Emile S. Gardiner

    2009-01-01

    Water oak (Quercus nigra L.) is a tardily deciduous species commonly planted in afforestation projects in the Lower Mississippi River Alluvial Valley, USA. Field performance is often marked by low survival rates and top dieback, which may be associated with poor physiological quality of planting stock.

  11. Species composition, Plant Community structure and Natural ...

    African Journals Online (AJOL)

    Belete forest is one of the very few remnant moist evergreen montane forests in Ethiopia. The objective of this work was to study the vegetation structure, composition and Natural regeneration status of Belete moist evergreen montane forest. To investigate the plant community structure, composition and regeneration status ...

  12. Endangered Species

    Science.gov (United States)

    EPA's Endangered Species Protection Program helps promote recovery of listed species. The ESPP determines if pesticide use in a geographic area may affect any listed species. Find needed limits on pesticide use in Endangered Species Protection Bulletins.

  13. Coping with drought-induced xylem cavitation: coordination of embolism repair and ionic effects in three Mediterranean evergreens.

    Science.gov (United States)

    Trifilò, Patrizia; Barbera, Piera M; Raimondo, Fabio; Nardini, Andrea; Lo Gullo, Maria A

    2014-02-01

    Embolism repair and ionic effects on xylem hydraulic conductance have been documented in different tree species. However, the diurnal and seasonal patterns of both phenomena and their actual role in plants' responses to drought-induced xylem cavitation have not been thoroughly investigated. This study provides experimental evidence of the ability of three Mediterranean species to maintain hydraulic function under drought stress by coordinating the refilling of xylem conduits and ion-mediated enhancement of stem hydraulic conductance (K stem). Vessel grouping indices and starch content in vessel-associated parenchyma cells were quantified to verify eventual correlations with ionic effects and refilling, respectively. Experiments were performed on stems of Ceratonia siliqua L., Olea europaea L. and Laurus nobilis L. Seasonal, ion-mediated changes in K stem (ΔK stem) and diurnal and/or seasonal embolism repair were recorded for all three species, although with different temporal patterns. Field measurements of leaf specific stem hydraulic conductivity showed that it remained quite constant during the year, despite changes in the levels of embolism. Starch content in vessel-associated parenchyma cells changed on diurnal and seasonal scales in L. nobilis and O. europaea but not in C. siliqua. Values of ΔK stem were significantly correlated with vessel multiple fraction values (the ratio of grouped vessels to total number of vessels). Our data suggest that the regulation of xylem water transport in Mediterranean plants relies on a close integration between xylem refilling and ionic effects. These functional traits apparently play important roles in plants' responses to drought-induced xylem cavitation.

  14. Plant functional types are more efficient than climate in predicting spectrums of trait variation in evergreen angiosperm trees of tropical Australia and China

    Science.gov (United States)

    Togashi, H. F.; Prentice, I. C. C.; Atkin, O. K.; Bloomfield, K. J.; Bradford, M.; Weerasinghe, L. K.; Harrison, S. P.; Evans, B. J.; Liddell, M. J.; Wang, H.; Cao, K. F.; Fan, Z.

    2015-12-01

    The representation of Plant Functional Types (PFTs) in current generation of Dynamic Global Vegetation Models (DGVMs) is excessively simplistically. Key ecophysiological properties, such as photosynthesis biochemistry, are most times merely averaged and trade-off with other plant traits is often neglected. Validation of a PFT framework based in photosynthetic process is crucial to improve reliability of DGVMs. We present 431 leaf-biochemical and wood level measurements in evergreen angiosperm trees of tropical forests in Australia and China that were divided in four spectrums of plant trait variation: metabolic, structural, hydraulic and height dimensions. Plant traits divided in each of these dimensions adopt survival strategies reflected more clearly by trade-off within each spectrum, and in some extent across spectrums. Co-ordination theory (that Rubisco- and electron-transport limited rates of photosynthesis are co-limiting) and least-coast theory (that intercellular to ambient CO2 concentration minimizes the combined costs per unit carbon assimilation, regulating maximum height and wood density) expectations matched PFT (which takes in account canopy position and light access, and life spam) variation. Our findings suggest that climate (air moisture, air temperature, light) has lower power representing these dimensions, in comparison to the PFT framework.

  15. Diversidad de plantas trepadoras y epífitas vasculares en un paisaje agroforestal del sur de chile: una comparación entre fragmentos de bosque nativo

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    Jimmy Pincheira-Ulbrich

    2012-12-01

    Full Text Available Se comparó la diversidad de plantas trepadoras y epífitas vasculares entre un fragmento de bosque siempreverde (Laureliopsis philippiana y Eucryphia cordifolia y cuatro fragmentos de bosque secundario dominados por Nothofagus obliqua en una matriz agroforestal en la precordillera costera de la provincia de Osorno (Chile. Sobre la base de un muestreo por transectos con observaciones desde la base del suelo, se obtuvo la riqueza de especies, la composición florística, la frecuencia de ocurrencia (fo y parámetros estructurales del bosque. Los resultados mostraron que: (1 la riqueza fue mayor en el fragmento siempreverde (19 especies y decreció en los fragmentos de N. obliqua (16 a 10 especies, (3 la familia Hymenophyllaceae (epíftas fue el grupo más diverso (10 especies, y con mayor fo en el fragmento siempreverde, (4 las trepadoras incrementaron su fo en los fragmentos de N. obliqua, (5 cuatro y cinco especies sólo se encontraron en el bosque siempreverde y N. obliqua, respectivamente, (6 la similitud florística varió entre 38 % y 75 % entre fragmentos, (7 el estado de desarrollo del bosque fue desigual entre las comunidades forestales. Se concluye que los cambios de diversidad de las especies ocurren por efecto de los cambios en la estructura del bosque.Vascular epiphytes and climbing plants diversity in an agroforestal landscape in southern Chile: a comparison among native forest fragments. We compared the diversity of vines and vascular epiphytes among an evergreen forest fragment (Laureliopsis philippiana y Eucryphia cordifolia and four fragments of secondary forest dominated for Nothofagus obliqua in an agro-forestry matrix landscape localized in the coastal range of Osorno, in Chile. Based on a sampling transects with ground-based observations, we obtained the species richness, floristic composition, frequency of occurrence (fo and forest structure. The results showed that: (1 the richness was higher in the evergreen forest (19

  16. Seed plant phylogenetic diversity and species richness in conservation planning within a global biodiversity hotspot in eastern Asia.

    Science.gov (United States)

    Li, Rong; Kraft, Nathan J B; Yu, Haiying; Li, Heng

    2015-12-01

    One of the main goals of conservation biology is to understand the factors shaping variation in biodiversity across the planet. This understanding is critical for conservation planners to be able to develop effective conservation strategies. Although many studies have focused on species richness and the protection of rare and endemic species, less attention has been paid to the protection of the phylogenetic dimension of biodiversity. We explored how phylogenetic diversity, species richness, and phylogenetic community structure vary in seed plant communities along an elevational gradient in a relatively understudied high mountain region, the Dulong Valley, in southeastern Tibet, China. As expected, phylogenetic diversity was well correlated with species richness among the elevational bands and among communities. At the community level, evergreen broad-leaved forests had the highest levels of species richness and phylogenetic diversity. Using null model analyses, we found evidence of nonrandom phylogenetic structure across the region. Evergreen broad-leaved forests were phylogenetically overdispersed, whereas other vegetation types tended to be phylogenetically clustered. We suggest that communities with high species richness or overdispersed phylogenetic structure should be a focus for biodiversity conservation within the Dulong Valley because these areas may help maximize the potential of this flora to respond to future global change. In biodiversity hotspots worldwide, we suggest that the phylogenetic structure of a community may serve as a useful measure of phylogenetic diversity in the context of conservation planning. © 2015 Society for Conservation Biology.

  17. Patterns and determinants of mammal species occurrence in India

    Science.gov (United States)

    Karanth, K.K.; Nichols, J.D.; Hines, J.E.; Karanth, K.U.; Christensen, N.L.

    2009-01-01

    Many Indian mammals face range contraction and extinction, but assessments of their population status are hindered by the lack of reliable distribution data and range maps. 2. We estimated the current geographical ranges of 20 species of large mammals by applying occupancy models to data from country-wide expert. We modelled species in relation to ecological and social covariates (protected areas, landscape characteristics and human influences) based on a priori hypotheses about plausible determinants of mammalian distribution patterns. 3. We demonstrated that failure to incorporate detection probability in distribution survey methods underestimated habitat occupancy for all species. 4. Protected areas were important for the distribution of 16 species. However, for many species much of their current range remains unprotected. The availability of evergreen forests was important for the occurrence of 14 species, temperate forests for six species, deciduous forests for 15 species and higher altitude habitats for two species. Low human population density was critical for the occurrence of five species, while culturally based tolerance was important for the occurrence of nine other species. 5. Rhino Rhinoceros unicornis, gaur Bos gaurus and elephant Elephas maximus showed the most restricted ranges among herbivores, and sun bear Helarctos malayanus, brown bear Ursus arctos and tiger Panthera tigris were most restricted among carnivores. While cultural tolerance has helped the survival of some mammals, legal protection has been critically associated with occurrence of most species. 6. Synthesis and applications. Extent of range is an important determinant of species conservation status. Understanding the relationship of species occurrence with ecological and socio-cultural covariates is important for identification and management of key conservation areas. The combination of occupancy models with field data from country-wide experts enables reliable estimation of species

  18. Antimicrobial Potential, Identification and Phylogenetic Affiliation of Wild Mushrooms from Two Sub-Tropical Semi-Evergreen Indian Forest Ecosystems.

    Science.gov (United States)

    Lallawmsanga; Passari, Ajit Kumar; Mishra, Vineet Kumar; Leo, Vincent Vineeth; Singh, Bhim Pratap; Valliammai Meyyappan, Geetha; Gupta, Vijai Kumar; Uthandi, Sivakumar; Upadhyay, Ramesh Chandra

    2016-01-01

    The diversity of wild mushrooms was investigated from two protected forest areas in India and 231 mushroom specimens were morphologically identified. Among them, 76 isolates were screened for their antimicrobial potential against seven bacterial and fungal pathogens. Out of 76 isolates, 45 isolates which displayed significant antimicrobial activities were identified using ITS rRNA gene amplification and subsequently phylogenetically characterized using random amplified polymorphic DNA (RAPD) and inter-simple sequence repeat (ISSR) markers. Sequencing of the ITS rRNA region classified the isolates into 16 genera belonging to 11 families. In total, 11 RAPD and 10 ISSR primers were selected to evaluate genetic diversity based on their banding profile produced. In total 337 RAPD and 312 ISSR bands were detected, among which percentage of polymorphism ranges from 34.2% to 78.8% and 38.6% to 92.4% by using RAPD and ISSR primers respectively. Unweighted Pair-Group Method with Arithmetic Mean (UPGMA) trees of selected two methods were structured similarly, grouping the 46 isolates into two clusters which clearly showed a significant genetic distance among the different strains of wild mushroom, with an similarity coefficient ranges from 0.58 to 1.00 and 0.59 to 1.00 with RAPD and ISSR analysis respectively. This reporthas highlighted both DTR and MNP forests provide a habitat for diverse macrofungal species, therefore having the potential to be used for the discovery of antimicrobials. The report has also demonstrated that both RAPD and ISSR could efficiently differentiate wild mushrooms and could thus be considered as efficient markers for surveying genetic diversity. Additionally, selected six wild edible mushroom strains (Schizophyllum commune BPSM01, Panusgiganteus BPSM27, Pleurotussp. BPSM34, Lentinussp. BPSM37, Pleurotusdjamor BPSM41 and Lentinula sp. BPSM45) were analysed for their nutritional (proteins, carbohydrates, fat and ash content), antioxidant potential

  19. Development of defoliating insects and their preferences for host plants under varying temperatures in a subtropical evergreen forest in eastern China

    Science.gov (United States)

    Jing, Jun; Xia, Lingdan; Li, Kai

    2016-09-01

    The aim of this work was to understand the development of defoliating insects and their preferences for host plants under varying temperatures in a subtropical evergreen broad-leaved forest in China. We measured the main developmental parameters of three typical defoliating insects (i.e., Ourapteryx ebuleata szechuana, Biston marginata, and Euproctis angulata) and their preferences for five host plants at temperatures from 16°C to 31°C at 3°C intervals in the Tiantong National Forest Research station in eastern China. The results showed the following. 1) An appropriate rise in temperature increases the survival rate with an increase in the number of offspring. The developmental durations for these three insects were shortened, and pupal weight increased with an increase in temperature. 2) A shift in the preference for host plants for these three insects was observedat elevated temperatures. They all preferred to feed on Schima superba and Castanopsis sclerophylla at elevated temperatures, showing an opposite response to the other three plants. The daily leaf consumption of the three insects was positively correlated with their feeding preference, with more leaves being consumed from the plants they preferred. 3) For O. ebuleata szechuana larvae, daily leaf consumption initially increased and then decreased with increasing temperatures. In contrast, Biston marginata and Euproctis angulata larvae consumed more leaves at elevated temperatures. The feeding preferences of O. ebuleata szechuana and Biston marginata were more sensitive to changing temperatures than that of Euproctis angulata laevae. We concluded that increased numbers of offspring and generations, pupal weights, and a shift in preference to two plants for these three defoliating insects might lead to severe damage to these two plants which would enhance the fragmentation and decrease the stability of the forest communities under changing temperatures. Meanwhile, the variations in the responses of

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

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    E. V. J. Tanner

    2016-11-01

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

  1. Accuracy of LiDAR-based tree height estimation and crown recognition in a subtropical evergreen broad-leaved forest in Okinawa, Japan

    Directory of Open Access Journals (Sweden)

    Azita Ahmad Zawawi

    2015-04-01

    Full Text Available Aim of study: To present an approach for estimating tree heights, stand density and crown patches using LiDAR data in a subtropical broad-leaved forest. Area of study: The study was conducted within the Yambaru subtropical evergreen broad-leaved forest, Okinawa main island, Japan. Materials and methods: A digital canopy height model (CHM was extracted from the LiDAR data for tree height estimation and a watershed segmentation method was applied for the individual crown delineation. Dominant tree canopy layers were estimated using multi-scale filtering and local maxima detection. The LiDAR estimation results were then compared to the ground inventory data and a high resolution orthophoto image for accuracy assessment. Main results: A Wilcoxon matched pair test suggests that LiDAR data is highly capable of estimating tree height in a subtropical forest (z = 4.0, p = 0.345, but has limitation to detect small understory trees and a single tree delineation. The results show that there is a statistically significant different type of crown detection from LiDAR data over forest inventory (z = 0, p = 0.043. We also found that LiDAR computation results underestimated the stand density and overestimated the crown size. Research highlights: Most studies involving crown detection and tree height estimation have focused on the analysis of plantations, boreal forests and temperate forests, and less was conducted on tropical and/or subtropical forests. Our study tested the capability of LiDAR as an effective application for analyzing a highly dense forest

  2. Pleiotropic phenotypes of the salt-tolerant and cytosine hypomethylated leafless inflorescence, evergreen dwarf and irregular leaf lamina mutants of Catharanthus roseus possessing Mendelian inheritance.

    Science.gov (United States)

    Kumari, Renu; Sharma, Vishakha; Sharma, Vinay; Kumar, Sushil

    2013-12-01

    In Catharanthus roseus, three morphological cum salt-tolerant chemically induced mutants of Mendelian inheritance and their wild-type parent cv Nirmal were characterized for overall cytosine methylation at DNA repeats, expression of 119 protein coding and seven miRNA-coding genes and 50 quantitative traits. The mutants, named after their principal morphological feature(s), were leafless inflorescence (lli), evergreen dwarf (egd) and irregular leaf lamina (ill). The Southern-blot analysis of MspI digested DNAs of mutants probed with centromeric and 5S and 18S rDNA probes indicated that, in comparison to wild type, the mutants were extensively demethylated at cytosine sites. Among the 126 genes investigated for transcriptional expression, 85 were upregulated and 41 were downregulated in mutants. All of the five genes known to be stress responsive had increased expression in mutants. Several miRNA genes showed either increased or decreased expression in mutants. The C. roseus counterparts of CMT3, DRM2 and RDR2 were downregulated in mutants. Among the cell, organ and plant size, photosynthesis and metabolism related traits studied, 28 traits were similarly affected in mutants as compared to wild type. Each of the mutants also expressed some traits distinctively. The egd mutant possessed superior photosynthesis and water retention abilities. Biomass was hyperaccumulated in roots, stems, leaves and seeds of the lli mutant. The ill mutant was richest in the pharmaceutical alkaloids catharanthine, vindoline, vincristine and vinblastine. The nature of mutations, origins of mutant phenotypes and evolutionary importance of these mutants are discussed.

  3. The plant economics spectrum is structured by leaf habits and growth forms across subtropical species.

    Science.gov (United States)

    Zhao, Yan-Tao; Ali, Arshad; Yan, En-Rong

    2017-02-01

    The plant economics spectrum that integrates the combination of leaf and wood syndromes provides a useful framework for the examination of species strategies at the whole-plant level. However, it remains unclear how species that differ in leaf habits and growth forms are integrated within the plant economics spectrum in subtropical forests. We measured five leaf and six wood traits across 58 subtropical plant species, which represented two leaf habits (evergreen vs deciduous) and two growth forms (tree vs shrub) in eastern China. Principal component analysis (PCA) was employed separately to construct the leaf (LES), wood (WES) and whole-plant (WPES) economics spectra. Leaf and wood traits are highly intra- and intercorrelated, thus defining not only the LES and WES, but also a WPES. Multi-trait variations in PCAs revealed that the traits which were representative of the acquisitive strategy, i.e., cheap tissue investment and rapid returns on that investment, were clustered at one end, while traits that represented the conservative strategy, i.e., expensive tissue investment and slower returns, were clustered at other end in each of the axes of the leaf and wood syndromes (PC1-axis) and the plant height strategy (PC2-axis). The local WPES, LES and WES were tightly correlated with each other. Evergreens shaped the conservative side, while deciduous species structured the acquisitive side of the WPES and LES. With respect to plant height strategies, trees formulated the acquisitive side and shrub species made up the conservative side of the WPES, LES and WES. In conclusion, our results suggested that the LES and WES were coordinated to a WPES for subtropical species. The finding of this local spectrum of plant form and function would be beneficial for modeling nutrient fluxes and species compositions in the changing climate, but also for understanding species strategies in an evolutionary context. © The Author 2016. Published by Oxford University Press. All rights

  4. Geological Substrates Shape Tree Species and Trait Distributions in African Moist Forests

    Science.gov (United States)

    Fayolle, Adeline; Engelbrecht, Bettina; Freycon, Vincent; Mortier, Frédéric; Swaine, Michael; Réjou-Méchain, Maxime; Doucet, Jean-Louis; Fauvet, Nicolas; Cornu, Guillaume; Gourlet-Fleury, Sylvie

    2012-01-01

    Background Understanding the factors that shape the distribution of tropical tree species at large scales is a central issue in ecology, conservation and forest management. The aims of this study were to (i) assess the importance of environmental factors relative to historical factors for tree species distributions in the semi-evergreen forests of the northern Congo basin; and to (ii) identify potential mechanisms explaining distribution patterns through a trait-based approach. Methodology/Principal Findings We analyzed the distribution patterns of 31 common tree species in an area of more than 700,000 km2 spanning the borders of Cameroon, the Central African Republic, and the Republic of Congo using forest inventory data from 56,445 0.5-ha plots. Spatial variation of environmental (climate, topography and geology) and historical factors (human disturbance) were quantified from maps and satellite records. Four key functional traits (leaf phenology, shade tolerance, wood density, and maximum growth rate) were extracted from the literature. The geological substrate was of major importance for the distribution of the focal species, while climate and past human disturbances had a significant but lesser impact. Species distribution patterns were significantly related to functional traits. Species associated with sandy soils typical of sandstone and alluvium were characterized by slow growth rates, shade tolerance, evergreen leaves, and high wood density, traits allowing persistence on resource-poor soils. In contrast, fast-growing pioneer species rarely occurred on sandy soils, except for Lophira alata. Conclusions/Significance The results indicate strong environmental filtering due to differential soil resource availability across geological substrates. Additionally, long-term human disturbances in resource-rich areas may have accentuated the observed patterns of species and trait distributions. Trait differences across geological substrates imply pronounced

  5. Do temperate tree species diversity and identity influence soil microbial community function and composition?

    Science.gov (United States)

    Khlifa, Rim; Paquette, Alain; Messier, Christian; Reich, Peter B; Munson, Alison D

    2017-10-01

    Studies of biodiversity-ecosystem function in treed ecosystems have generally focused on aboveground functions. This study investigates intertrophic links between tree diversity and soil microbial community function and composition. We examined how microbial communities in surface mineral soil responded to experimental gradients of tree species richness (SR), functional diversity (FD), community-weighted mean trait value (CWM), and tree identity. The site was a 4-year-old common garden experiment near Montreal, Canada, consisting of deciduous and evergreen tree species mixtures. Microbial community composition, community-level physiological profiles, and respiration were evaluated using phospholipid fatty acid (PLFA) analysis and the MicroResp™ system, respectively. The relationship between tree species richness and glucose-induced respiration (GIR), basal respiration (BR), metabolic quotient (qCO 2) followed a positive but saturating shape. Microbial communities associated with species mixtures were more active (basal respiration [BR]), with higher biomass (glucose-induced respiration [GIR]), and used a greater number of carbon sources than monocultures. Communities associated with deciduous tree species used a greater number of carbon sources than those associated with evergreen species, suggesting a greater soil carbon storage capacity. There were no differences in microbial composition (PLFA) between monocultures and SR mixtures. The FD and the CWM of several functional traits affected both BR and GIR. In general, the CWM of traits had stronger effects than did FD, suggesting that certain traits of dominant species have more effect on ecosystem processes than does FD. Both the functions of GIR and BR were positively related to aboveground tree community productivity. Both tree diversity (SR) and identity (species and functional identity-leaf habit) affected soil microbial community respiration, biomass, and composition. For the first time, we identified

  6. Geological substrates shape tree species and trait distributions in African moist forests.

    Directory of Open Access Journals (Sweden)

    Adeline Fayolle

    Full Text Available BACKGROUND: Understanding the factors that shape the distribution of tropical tree species at large scales is a central issue in ecology, conservation and forest management. The aims of this study were to (i assess the importance of environmental factors relative to historical factors for tree species distributions in the semi-evergreen forests of the northern Congo basin; and to (ii identify potential mechanisms explaining distribution patterns through a trait-based approach. METHODOLOGY/PRINCIPAL FINDINGS: We analyzed the distribution patterns of 31 common tree species in an area of more than 700,000 km(2 spanning the borders of Cameroon, the Central African Republic, and the Republic of Congo using forest inventory data from 56,445 0.5-ha plots. Spatial variation of environmental (climate, topography and geology and historical factors (human disturbance were quantified from maps and satellite records. Four key functional traits (leaf phenology, shade tolerance, wood density, and maximum growth rate were extracted from the literature. The geological substrate was of major importance for the distribution of the focal species, while climate and past human disturbances had a significant but lesser impact. Species distribution patterns were significantly related to functional traits. Species associated with sandy soils typical of sandstone and alluvium were characterized by slow growth rates, shade tolerance, evergreen leaves, and high wood density, traits allowing persistence on resource-poor soils. In contrast, fast-growing pioneer species rarely occurred on sandy soils, except for Lophira alata. CONCLUSIONS/SIGNIFICANCE: The results indicate strong environmental filtering due to differential soil resource availability across geological substrates. Additionally, long-term human disturbances in resource-rich areas may have accentuated the observed patterns of species and trait distributions. Trait differences across geological substrates imply

  7. Geological substrates shape tree species and trait distributions in African moist forests.

    Science.gov (United States)

    Fayolle, Adeline; Engelbrecht, Bettina; Freycon, Vincent; Mortier, Frédéric; Swaine, Michael; Réjou-Méchain, Maxime; Doucet, Jean-Louis; Fauvet, Nicolas; Cornu, Guillaume; Gourlet-Fleury, Sylvie

    2012-01-01

    Understanding the factors that shape the distribution of tropical tree species at large scales is a central issue in ecology, conservation and forest management. The aims of this study were to (i) assess the importance of environmental factors relative to historical factors for tree species distributions in the semi-evergreen forests of the northern Congo basin; and to (ii) identify potential mechanisms explaining distribution patterns through a trait-based approach. We analyzed the distribution patterns of 31 common tree species in an area of more than 700,000 km(2) spanning the borders of Cameroon, the Central African Republic, and the Republic of Congo using forest inventory data from 56,445 0.5-ha plots. Spatial variation of environmental (climate, topography and geology) and historical factors (human disturbance) were quantified from maps and satellite records. Four key functional traits (leaf phenology, shade tolerance, wood density, and maximum growth rate) were extracted from the literature. The geological substrate was of major importance for the distribution of the focal species, while climate and past human disturbances had a significant but lesser impact. Species distribution patterns were significantly related to functional traits. Species associated with sandy soils typical of sandstone and alluvium were characterized by slow growth rates, shade tolerance, evergreen leaves, and high wood density, traits allowing persistence on resource-poor soils. In contrast, fast-growing pioneer species rarely occurred on sandy soils, except for Lophira alata. The results indicate strong environmental filtering due to differential soil resource availability across geological substrates. Additionally, long-term human disturbances in resource-rich areas may have accentuated the observed patterns of species and trait distributions. Trait differences across geological substrates imply pronounced differences in population and ecosystem processes, and call for different

  8. Monitoring on species diversity of macrofungi in Khek watershed, Phetchabun Province

    Directory of Open Access Journals (Sweden)

    Duengkae, K.

    2006-03-01

    Full Text Available A study on monitoring species diversity of macrofungi was conducted in the Khek watershed, Phetchabun Province from 2002 to 2004. Permanent plots were used to determine species diversity, compositionand changing of macrofungi. The results of this study indicate the occurrence of 119 species from 76 genera and 33 families. Species were classified into the Phylum Ascomycota (12 species and 8 genera and the Phylum Basidiomycota (107 species and 68 genera. The most common families were Polyporaceae, Stereaceae andHymenochaetaceae. The most common genera were Xylaria, Microporus, Trametes, Hymenochaete and Stereum. The species Microporus xanthopus was found in almost every forest type the year-round, and occurred on soil most frequently (35 species, 30%. Species diversity and species indices were greatest during the 2003 rain season in evergreen and secondary forests. Species diversity and species index between plant community were not significantly different (Kruskal-Wallis test; X2 = 5.394, P = 0.249 and X2 = 9.158, P = 0.057. In addition, this research suggested that some species were edible and potentially served as medicines. Consequently, effective policies and conservation plans should be soon enough established for sustainable use of macrofungi in this watershed area.

  9. Biogeochemical and Ecomorphological Niche Segregation of Mediterranean Woody Species along a Local Gradient

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    Enrique G. de la Riva

    2017-07-01

    Full Text Available According with niche theory the species are specialized in different ecological niches, being able to coexist as result of a differential use of resources. In this context, the biogeochemical niche hypothesis proposes that species have an optimal elemental composition which results from the link between the chemical and morphological traits for the optimum plant functioning. Thus, and attending to the limiting similarity concept, different elemental composition and plant structure among co-occurring species may reduce competition, promoting different functional niches. Different functional habits associated with leaf life-span or growth forms are associated with different strategies for resource uptake, which could promote niche partitioning. In the present study, based on the biogeochemical niche concept and the use of resources in different proportions, we have focused on leaf traits (morphological and chemical associated with resource uptake, and explored the niche partitioning among functional habits: leaf life-span (deciduous, evergreen, and semideciduous and growth (tree, shrub, and arborescent-shrub. To this end, we have quantified the hypervolume of the leaf functional trait space (both structure and chemical composition in a sample of 45 Mediterranean woody species from Sierra Morena Mountains (Spain growing along a local soil resource gradient. Our results show consistent variation in functional space for woody communities distributed along the environmental gradient. Thus, communities dominated by deciduous trees with faster growth and a predominant acquisitive strategy were characteristic of bottom forests and showed highest leaf biogeochemical space. While semideciduous shrubs and evergreen (arborescent, trees species, characterized by a conservative strategy, dominated ridge forests and showed smaller functional space. In addition, within each topographical zone or environment type, the foliar biogeochemical niche partitioning

  10. Invasive Species

    Science.gov (United States)

    Invasive species have significantly changed the Great Lakes ecosystem. An invasive species is a plant or animal that is not native to an ecosystem, and whose introduction is likely to cause economic, human health, or environmental damage.

  11. Begonia wui-senioris (sect. Platycentrum, Begoniaceae), a new species from Myanmar.

    Science.gov (United States)

    Peng, Ching-I; Wang, Hong; Kono, Yoshiko; Yang, Hsun-An

    2014-12-01

    The flora of Myanmar is under-collected compared with all other tropical Asian countries. An unknown Begonia was grown from seeds collected from a limestone hill in Central Myanmar, and compared with potentially allied species. The unknown Begonia is rhizomatous, has peltate leaves, 2-locular ovaries, and is evergreen. It is clearly assignable to sect. Platycentrum. Only two other species of Begonia, B. josephii and B. subperfoliata, in Myanmar have peltate leaves, but they are deciduous tuberous plants with 3-locular ovaries and belong to sect. Diploclinium. Thorough studies of literature and herbarium materials support the recognition of a new species, Begonia wui-senioris, which is fully described and illustrated. Begonia wui-senioris has the lowest chromosome number (2n = 14) for the genus.

  12. Ecological Value of Soil Organic Matter at Tropical Evergreen Aglaia-Streblus Forest of Meru Betiri National Park, East Java, Indonesia

    Directory of Open Access Journals (Sweden)

    Hari Sulistiyowati

    2016-09-01

    Full Text Available As part of carbon pools, forest soil stores soil organic matter (SOM that contains many elements including organic C, N, P, and K. These elements contribute nutrients for biogeochemical cycles within the ecosystem. This study was done to determine the ecological value of forest soil organic matter at tropical evergreen Aglaia-Streblus forest of Meru Betiri National Park (MBNP, East Java, Indonesia. The data were sampled along gradient topography in Pringtali tropical forest of TMBNP. Direct measurements of soil moisture, temperature, and pH were taken in the field. The soil samples were extracted from 6 points of soil solum using soil auger, and then oven-dried to get value of dry-weight. The elements content of organic C, N, P, and K were analyzed and estimated at the laboratory. The ecoval of SOM was appraised using developed ecological valuation tool. The result showed that SOM contributed higher ecoval of organic C (66.03 Mg ha-1 than other elements. Compared to P and K elements, N had the highest stock of element content. However, comparing to other two tropical forest ecosystems of Asia the ecoval of SOM elements in TMBNP was relatively low because of its natural geomorphological features.The ecoval of SOM elements in TMBNP was relatively low because of its natural geomorphological features. The ecovals contributed about 2.440,64 - 6.955,50 USD or 31.271.923,73 - 89.120.837,23 IDR per hectare of ecological value (d to the ecosystem. This value was mainly contributed by organic C stock in the TMBNP forest SOM. It means the forest SOM had higher element content of organic C than N, P, and K elements. This d value is an indicator for TMBNP to protect the SOM elements meaning protecting their resources to sustain the biogeochemical cycles in the forest ecosystem. All the management and policy correlated to this protected area should consider this valuable information for their plan and actions.

  13. Seedling density according to structure, dominance and understory cover in old-growth forest stands of the evergreen forest type in the coastal range of Chile Densidad de plántulas de acuerdo a la estructura, dominancia y cobertura del sotobosque en bosques siempreverdes adultos en la cordillera de la Costa de Chile

    Directory of Open Access Journals (Sweden)

    Pablo J. Donoso

    2005-03-01

    Full Text Available Securing timely regeneration is essential in maintaining the long-term ecological or silvicultural functions and values of forests. Its establishment, in turn, depends on many factors, including the structure and composition of the forest itself. Available information shows that seedling density varies greatly across the evergreen forest type in Chile. Yet stand variables that may affect the establishment of advance regeneration have not been studied. To that end, we evaluated seven stands of the coastal range, within the northern part of the evergreen forest type (39°14'-40°16' S. We documented understory cover, tree density and dominance, and stand structure, and used the information to assess their effects over seedling density. Findings indicate that Laurelia philippiana was the dominant canopy and regenerating species in these stands. Also, seedling density was significantly greater in stands at lower elevations where shade-tolerant Aextoxicon punctatum was important. Chusquea spp. and Lophosoria quadripinnata, both understory species, had a significant negative effect on seedling density. Basal area and canopy cover, per se, showed little relationship with seedling density. Vertical structure, evaluated through a crown index, had a significant relationship with seedling density, but the direction depended on the species (e.g., L. philippiana and A. punctatum and the diameter structure within our plots. Fitted models that included these variables were highly significant, and in most cases their significance increased considerably (14 to 26 % when we accounted for the diameter structures of the plotsLa regeneración es esencial para mantener en el largo plazo las funciones y valores ecológicos o silviculturales de los bosques. Su establecimiento depende de varios factores, incluyendo la estructura y composición del bosque. La información disponible indica que existe una gran variabilidad en la densidad de plántulas a través de la

  14. Foliage efficiency of forest-forming species in the climatic gradients of Eurasia

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    V. A. Usoltsev

    2017-08-01

    Full Text Available The paperis of the scientific area of biogeography and devoted to a new aspect in the study of biological productivity of forest ecosystems on a geographical basis, expressed indirectly by climate parameters, namely, the foliage efficiency that until now is not investigated at the global level. Foliage efficiency is the ratio of net primary production (NPP to foliage biomass and is expressed in relative units. Some features of change of foliage efficiency of vicarious forest-forming species in Eurasian transcontinental gradients are showed for the first time using the voluminous factual material. The set of published biomass and NPP data (t/ha obtained in a number of 2192 plots is compiled. Using multiple regression analysis technique, the statistically significant changes in foliage efficiency values according to two transcontinental gradients, namely by zonal belts and continentality of climate, are stated for each forest-forming species. The species-specificity of age dynamics of stem volume and foliage efficiency is shown. It is monotonically decreased almost for all tree species in the following order: spruce and fir, pine, birch, oak, larch and aspen-poplar. When climate continentality increasing, foliage efficiency values of mature forests is dropping, most intensively in pines, less intensive in deciduous forests and virtually no changes in spruce-fir communities. In zonal gradient from the northern temperate to the subequatorial belt, foliage efficiency of deciduous species decreases, but it of the evergreen spruce and pine increases in the same direction. One of the possible causes of these opposite zonal trends of foliage efficiency in evergreen and deciduous species consists in different conditions of physiological processes in the year cycle, in particular, in year-round assimilates accumulation in the first and seasonal one in the second.

  15. Modelling tree ring cellulose δ18O variations in two temperature-sensitive tree species from North and South America

    Science.gov (United States)

    Lavergne, Aliénor; Gennaretti, Fabio; Risi, Camille; Daux, Valérie; Boucher, Etienne; Savard, Martine M.; Naulier, Maud; Villalba, Ricardo; Bégin, Christian; Guiot, Joël

    2017-11-01

    Oxygen isotopes in tree rings (δ18OTR) are widely used to reconstruct past climates. However, the complexity of climatic and biological processes controlling isotopic fractionation is not yet fully understood. Here, we use the MAIDENiso model to decipher the variability in δ18OTR of two temperature-sensitive species of relevant palaeoclimatological interest (Picea mariana and Nothofagus pumilio) and growing at cold high latitudes in North and South America. In this first modelling study on δ18OTR values in both northeastern Canada (53.86° N) and western Argentina (41.10° S), we specifically aim at (1) evaluating the predictive skill of MAIDENiso to simulate δ18OTR values, (2) identifying the physical processes controlling δ18OTR by mechanistic modelling and (3) defining the origin of the temperature signal recorded in the two species. Although the linear regression models used here to predict daily δ18O of precipitation (δ18OP) may need to be improved in the future, the resulting daily δ18OP values adequately reproduce observed (from weather stations) and simulated (by global circulation model) δ18OP series. The δ18OTR values of the two species are correctly simulated using the δ18OP estimation as MAIDENiso input, although some offset in mean δ18OTR levels is observed for the South American site. For both species, the variability in δ18OTR series is primarily linked to the effect of temperature on isotopic enrichment of the leaf water. We show that MAIDENiso is a powerful tool for investigating isotopic fractionation processes but that the lack of a denser isotope-enabled monitoring network recording oxygen fractionation in the soil-vegetation-atmosphere compartments limits our capacity to decipher the processes at play. This study proves that the eco-physiological modelling of δ18OTR values is necessary to interpret the recorded climate signal more reliably.

  16. Cryptic diversity within the narrowly endemic Lerista wilkinsi group of north Queensland-two new species (Reptilia: Scincidae).

    Science.gov (United States)

    Couper, Patrick J; Amey, Andrew P; Wilmer, Jessica Worthington

    2016-09-08

    Herein we describe two new species of the skink genus Lerista from north-eastern Queensland, based on morphological and genetic data.  Additionally, we redescribe L. cinerea as this species is morphologically more variable than previously suggested.  We allocate these three species to the L. wilkinsi group (Greer et al. 1983) which is here identified as an endemic Queensland radiation, comprising L. ameles, L. cinerea, L. hobsoni sp. nov., L. storri, L. vanderduysi sp. nov., L. vittata and L. wilkinsi.  A number of these species have strong associations with semi-evergreen vine thickets, listed as an endangered habitat under the Australian Environment Protection and Biodiversity Conservation Act (1999).

  17. Interspecific differences in whole-plant respiration vs. biomass scaling relationships: a case study using evergreen conifer and angiosperm tree seedlings.

    Science.gov (United States)

    Cheng, Dongliang; Niklas, Karl J; Zhong, Quanlin; Yang, Yusheng; Zhang, Jianhua

    2014-04-01

    Empirical studies and theory indicate that respiration rates (R) of small plants scale nearly isometrically with both leaf biomass (ML) and total plant biomass (MT). These predictions are based on angiosperm species and apply only across a small range of body mass. Whether these relationships hold true for different plants, such as conifers, remains unclear. We tested these predictions using the whole-plant maintenance respiration rates and the biomass allocation patterns of the seedlings of two conifer tree species and two angiosperm tree species. Model Type II regression protocols were used to compare the scaling exponents (α) and normalization constants (β) across all four species and within each of the four species. The data show that the scaling exponents varied among the four species and that all differed significantly from isometry. For conifers, scaling exponents for R vs. MT, and R and ML were numerically smaller than those of the broadleaved angiosperm species. However, across the entire data set, R scaled isometrically with ML and with MT as predicted by the West, Brown, and Enquist (WBE) theory. We also observed higher respiration rates for small conifer seedlings compared to comparably sized angiosperm seedlings. Our data add credence to the view that the R vs. M scaling relationship differs among species, and that in general, the numerical values of this interspecific scaling relationship will depend on the species pooled in the analysis and on the range of body sizes within the data set.

  18. A striking new species of phytotelm-breeding tree frog (Anura: Rhacophoridae) from central Vietnam.

    Science.gov (United States)

    Rowley, Jodi J L; Le, Duong Thi Thuy; Dau, Vinh Quang; Hoang, Huy Duc; Cao, Trung Tien

    2014-04-02

    We describe a distinctive new species of phytotelm-breeding rhacophorid frog from central Vietnam. Gracixalus lumarius sp. nov. is distinguished from all other rhacophorids in Indochina by a combination of (1) medium body size (adult males 38.9-41.6 mm; adult female 36.3 mm), (2) dorsum brown diurnally and yellow nocturnally, (3) venter pink, (4) tympanum and supratympanic fold indistinct (5) iris dark gold with a dense, relatively uniformly distributed network of black reticulations, (6) dorsum with distinctive white conical tubercles in males, and (7) eggs deposited on wall of a phyptotelm. The new species is known from montane bamboo and montane evergreen forest in Ngoc Linh Nature Reserve in Kon Tum Province, between ~1845-2160 m elevation.

  19. Invasive species

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This is a summary of management activities and research related to invasive species on Neal Smith National Wildlife Refuge between 1992 and 2009. As part of the...

  20. Impacts of invading alien plant species on water flows at stand and catchment scales.

    Science.gov (United States)

    Le Maitre, D C; Gush, M B; Dzikiti, S

    2015-05-01

    There have been many studies of the diverse impacts of invasions by alien plants but few have assessed impacts on water resources. We reviewed the information on the impacts of invasions on surface runoff and groundwater resources at stand to catchment scales and covering a full annual cycle. Most of the research is South African so the emphasis is on South Africa's major invaders with data from commercial forest plantations where relevant. Catchment studies worldwide have shown that changes in vegetation structure and the physiology of the dominant plant species result in changes in surface runoff and groundwater discharge, whether they involve native or alien plant species. Where there is little change in vegetation structure [e.g. leaf area (index), height, rooting depth and seasonality] the effects of invasions generally are small or undetectable. In South Africa, the most important woody invaders typically are taller and deeper rooted than the native species. The impacts of changes in evaporation (and thus runoff) in dryland settings are constrained by water availability to the plants and, thus, by rainfall. Where the dryland invaders are evergreen and the native vegetation (grass) is seasonal, the increases can reach 300-400 mm/year. Where the native vegetation is evergreen (shrublands) the increases are ∼200-300 mm/year. Where water availability is greater (riparian settings or shallow water tables), invading tree water-use can reach 1.5-2.0 times that of the same species in a dryland setting. So, riparian invasions have a much greater impact per unit area invaded than dryland invasions. The available data are scattered and incomplete, and there are many gaps and issues that must be addressed before a thorough understanding of the impacts at the site scale can be gained and used in extrapolating to watershed scales, and in converting changes in flows to water supply system yields. Published by Oxford University Press on behalf of the Annals of Botany

  1. Phylogenetic and microscopic studies in the genus Lactifluus (Basidiomycota, Russulales) in West Africa, including the description of four new species.

    Science.gov (United States)

    Maba, Dao Lamèga; Guelly, Atsu K; Yorou, Nourou S; Verbeken, Annemieke; Agerer, Reinhard

    2015-06-01

    Despite the crucial ecological role of lactarioid taxa (Lactifluus, Lactarius) as common ectomycorrhiza formers in tropical African seasonal forests, their current diversity is not yet adequately assessed. During the last few years, numerous lactarioid specimens have been sampled in various ecosystems from Togo (West Africa). We generated 48 ITS sequences and aligned them against lactarioid taxa from other tropical African ecozones (Guineo-Congolean evergreen forests, Zambezian miombo). A Maximum Likelihood phylogenetic tree was inferred from a dataset of 109 sequences. The phylogenetic placement of the specimens, combined with morpho-anatomical data, supported the description of four new species from Togo within the monophyletic genus Lactifluus: within subgen. Lactifluus (L. flavellus), subgen. Russulopsis (L. longibasidius and L. pectinatus), and subgen. Edules (L. melleus). This demonstrates that the current species richness of the genus is considerably higher than hitherto estimated for African species and, in addition, a need to redefine the subgenera and sections within it.

  2. Why does Quercus suber species decline in Mediterranean areas?

    Directory of Open Access Journals (Sweden)

    Hae Naem Kim

    2017-09-01

    Full Text Available The cork oak (Quercus suber L. is a prevalent tree species in the Mediterranean climate zones of western Europe and north Africa with a quite narrow geographical range of distribution, as compared with the other Mediterranean evergreen oak species such as Quercus calliprinos (holly oak and Quercus ilex (holm oak. This species offers the ecological, economic and social importance, including their biodiversity and sustainable forest production in these areas. The increase of mean annual temperature and rainfall extremes during recent decades follows the trends predicted by present climate change models projecting a higher frequency of droughts and intense rain events in the Mediterranean climate areas. Nevertheless, various biotic and abiotic factors, including climate change (increased frequency and rigor of high temperature and drought and related physiological decline of trees, increases in the outbreaks of disease, and an excessive development of forest resources has been recognized as main factors to induce a cork oak forest decline. In general, sustainable cork oak forest management and proper agroforestry activity that can generate income for local people through local community participation would be the ways to prevent cork oak forest decline in northern Tunisia.

  3. Soil propagule banks of ectomycorrhizal fungi share many common species along an elevation gradient.

    Science.gov (United States)

    Miyamoto, Yumiko; Nara, Kazuhide

    2016-04-01

    We conducted bioassay experiments to investigate the soil propagule banks of ectomycorrhizal (EM) fungi in old-growth forests along an elevation gradient and compared the elevation pattern with the composition of EM fungi on existing roots in the field. In total, 150 soil cores were collected from three forests on Mt. Ishizuchi, western Japan, and subjected to bioassays using Pinus densiflora and Betula maximowicziana. Using molecular analyses, we recorded 23 EM fungal species in the assayed propagule banks. Eight species (34.8 %) were shared across the three sites, which ranged from a warm-temperate evergreen mixed forest to a subalpine conifer forest. The elevation pattern of the assayed propagule banks differed dramatically from that of EM fungi on existing roots along the same gradient, where only a small proportion of EM fungal species (3.5 %) were shared across sites. The EM fungal species found in the assayed propagule banks included many pioneer fungal species and composition differed significantly from that on existing roots. Furthermore, only 4 of 23 species were shared between the two host species, indicating a strong effect of bioassay host identity in determining the propagule banks of EM fungi. These results imply that the assayed propagule bank is less affected by climate compared to EM fungal communities on existing roots. The dominance of disturbance-dependent fungal species in the assayed propagule banks may result in higher ecosystem resilience to disturbance even in old-growth temperate forests.

  4. Zeaxanthin-independent energy quenching and alternative electron sinks cause a decoupling of the relationship between the photochemical reflectance index (PRI) and photosynthesis in an evergreen conifer during spring.

    Science.gov (United States)

    Fréchette, Emmanuelle; Wong, Christopher Y S; Junker, Laura Verena; Chang, Christine Yao-Yun; Ensminger, Ingo

    2015-12-01

    In evergreen conifers, the winter down-regulation of photosynthesis and its recovery during spring are the result of a reorganization of the chloroplast and adjustments of energy-quenching mechanisms. These phenological changes may remain undetected by remote sensing, as conifers retain green foliage during periods of photosynthetic down-regulation. The aim was to assess if the timing of the spring recovery of photosynthesis and energy-quenching characteristics are accurately monitored by the photochemical reflectance index (PRI) in the evergreen conifer Pinus strobus. The recovery of photosynthesis was studied using chlorophyll fluorescence, leaf gas exchange, leaf spectral reflectance, and photosynthetic pigment measurements. To assess if climate change might affect the recovery of photosynthesis, seedlings were exposed to cold spring conditions or warm spring conditions with elevated temperature. An early spring decoupling of the relationship between photosynthesis and PRI in both treatments was observed. This was caused by differences between the timing of the recovery of photosynthesis and the timing of carotenoid and chlorophyll pool size adjustments which are the main factors controlling PRI during spring. It was also demonstrated that zeaxanthin-independent NPQ mechanisms undetected by PRI further contributed to the early spring decoupling of the PRI-LUE relationship. An important mechanism undetected by PRI seems to involve increased electron transport around photosystem I, which was a significant energy sink during the entire spring transition, particularly in needles exposed to a combination of high light and cold temperatures. © The Author 2015. Published by Oxford University Press on behalf of the Society for Experimental Biology.

  5. Comparison of different discriminant functions for mangrove species analysis in Matang Mangrove Forest Reserve (MMFR), Perak based on statistical approach

    Science.gov (United States)

    Beh, Boon Chun; Tan, Kok Chooi; Mat Jafri, Mohd. Zubir; Lim, Hwee San

    2017-10-01

    Mangroves are known as salt-tolerant evergreen forests, whereas its create land-ocean interface ecosystems. Besides, mangroves bring direct and indirect benefits to human activities and play a major role as significant habitat for sustaining biodiversity. However, mangrove ecosystem study based on the mangrove species are very crucial to get a better understanding of their characteristics and ways to separate among them. In this paper, discriminant functions obtained using statistical approach were used to generate the score range for six mangrove species (Rhizophora apiculata, Acrostichum aurem, Acrostichum speciosum, Acanthus ilicifolius, Ceriops tagal and Sonneratia ovata) in Matang Mangrove Forest Reserve (MMFR), Perak. With the computation of score range for each species, the fraction of the species can be determined using the proposed algorithm. The results indicate that by using 11 discriminant functions out of 16 are more effective to separate the mangrove species as the higher accuracy was obtained. Overall, the determination of leaf sample's species is chosen base on the highest fraction measured among the six mangrove species. The obtained accuracy for mangrove species using statistical approach is low since it is impossible to successfully separate all the mangrove species in leaf level using their inherent reflectance properties. However, the obtained accuracy results are satisfactory and able to discriminate the examined mangrove species at species scale.

  6. SALMONELLA SPECIES

    African Journals Online (AJOL)

    DR. AMINU

    e. Biochemical screening and serological tests for Salmonellae. Identification of Salmonella species was done biochemically. Triple sugar Iron (TSI) agar motility, urease and citrate utilization tests were also used to screen the isolates before serologic testing was performed. (Cheesbrough, 2002; Perilla, 2003). Triple sugar ...

  7. Phytoplankton specie..

    African Journals Online (AJOL)

    each Station, samples for diversity data were collected by plankton net, which was towed at the surface water, while those for Spatial distribution and abundance were collected using a l l Van. Dorn water Sampler. A total of 13 Species belonging to 52 different genera were identified. Cyanobacteria were the most diverse ...

  8. Gas exchange recovery following natural drought is rapid unless limited by loss of leaf hydraulic conductance: evidence from an evergreen woodland.

    Science.gov (United States)

    Skelton, Robert P; Brodribb, Timothy J; McAdam, Scott A M; Mitchell, Patrick J

    2017-09-01

    Drought can cause major damage to plant communities, but species damage thresholds and postdrought recovery of forest productivity are not yet predictable. We used an El Niño drought event as a natural experiment to test whether postdrought recovery of gas exchange could be predicted by properties of the water transport system, or if metabolism, primarily high abscisic acid concentration, might delay recovery. We monitored detailed physiological responses, including shoot sapflow, leaf gas exchange, leaf water potential and foliar abscisic acid (ABA), during drought and through the subsequent rehydration period for a sample of eight canopy and understory species. Severe drought caused major declines in leaf water potential, elevated foliar ABA concentrations and reduced stomatal conductance and assimilation rates in our eight sample species. Leaf water potential surpassed levels associated with incipient loss of leaf hydraulic conductance in four species. Following heavy rainfall gas exchange in all species, except those trees predicted to have suffered hydraulic impairment, recovered to prestressed rates within 1 d. Recovery of plant gas exchange was rapid and could be predicted by the hydraulic safety margin, providing strong support for leaf vulnerability to water deficit as an index of damage under natural drought conditions. © 2017 The Authors. New Phytologist © 2017 New Phytologist Trust.

  9. Contrasting shrub species respond to early summer temperatures leading to correspondence of shrub growth patterns

    Science.gov (United States)

    Weijers, Stef; Pape, Roland; Löffler, Jörg; Myers-Smith, Isla H.

    2018-03-01

    The Arctic-alpine biome is warming rapidly, resulting in a gradual replacement of low statured species by taller woody species in many tundra ecosystems. In northwest North America, the remotely sensed normalized difference vegetation index (NDVI), suggests an increase in productivity of the Arctic and alpine tundra and a decrease in productivity of boreal forests. However, the responses of contrasting shrub species growing at the same sites to climate drivers remain largely unexplored. Here, we test growth, climate, and NDVI relationships of two contrasting species: the expanding tall deciduous shrub Salix pulchra and the circumarctic evergreen dwarf shrub Cassiope tetragona from an alpine tundra site in the Pika valley in the Kluane Region, southwest Yukon Territories, Canada. We found that annual growth variability of both species at this site is strongly driven by early summer temperatures, despite their contrasting traits and habitats. Shrub growth chronologies for both species were correlated with the regional climate signal and showed spatial correspondence with interannual variation in NDVI in surrounding alpine and Arctic regions. Our results suggest that early summer warming represents a common driver of vegetation change for contrasting shrub species growing in different habitats in the same alpine environments.

  10. Species abundance in a forest community in South China: A case of poisson lognormal distribution

    Science.gov (United States)

    Yin, Z.-Y.; Ren, H.; Zhang, Q.-M.; Peng, S.-L.; Guo, Q.-F.; Zhou, G.-Y.

    2005-01-01

    Case studies on Poisson lognormal distribution of species abundance have been rare, especially in forest communities. We propose a numerical method to fit the Poisson lognormal to the species abundance data at an evergreen mixed forest in the Dinghushan Biosphere Reserve, South China. Plants in the tree, shrub and herb layers in 25 quadrats of 20 m??20 m, 5 m??5 m, and 1 m??1 m were surveyed. Results indicated that: (i) for each layer, the observed species abundance with a similarly small median, mode, and a variance larger than the mean was reverse J-shaped and followed well the zero-truncated Poisson lognormal; (ii) the coefficient of variation, skewness and kurtosis of abundance, and two Poisson lognormal parameters (?? and ??) for shrub layer were closer to those for the herb layer than those for the tree layer; and (iii) from the tree to the shrub to the herb layer, the ?? and the coefficient of variation decreased, whereas diversity increased. We suggest that: (i) the species abundance distributions in the three layers reflects the overall community characteristics; (ii) the Poisson lognormal can describe the species abundance distribution in diverse communities with a few abundant species but many rare species; and (iii) 1/?? should be an alternative measure of diversity.

  11. Phenolic profile within the fine-root branching orders of an evergreen species highlights a disconnect in root tissue quality predicted by elemental- and molecular-level carbon composition.

    Science.gov (United States)

    Wang, Jun-Jian; Tharayil, Nishanth; Chow, Alex T; Suseela, Vidya; Zeng, Hui

    2015-06-01

    Fine roots constitute a significant source of plant productivity and litter turnover across terrestrial ecosystems, but less is known about the quantitative and qualitative profile of phenolic compounds within the fine-root architecture, which could regulate the potential contribution of plant roots to the soil organic matter pool. To understand the linkage between traditional macro-elemental and morphological traits of roots and their molecular-level carbon chemistry, we analyzed seasonal variations in monomeric yields of the free, bound, and lignin phenols in fine roots (distal five orders) and leaves of Ardisia quinquegona. Fine roots contained two-fold higher concentrations of bound phenols and three-fold higher concentrations of lignin phenols than leaves. Within fine roots, the concentrations of free and bound phenols decreased with increasing root order, and seasonal variation in the phenolic profile was more evident in lower order than in higher order roots. The morphological and macro-elemental root traits were decoupled from the quantity, composition and tissue association of phenolic compounds, revealing the potential inability of these traditional parameters to capture the molecular identity of phenolic carbon within the fine-root architecture and between fine roots and leaves. Our results highlight the molecular-level heterogeneity in phenolic carbon composition within the fine-root architecture, and imply that traits that capture the molecular identity of the root construct might better predict the decomposition dynamics within fine-root orders. © 2015 The Authors. New Phytologist © 2015 New Phytologist Trust.

  12. Scaling Chromosomes for an Evolutionary Karyotype: A Chromosomal Tradeoff between Size and Number across Woody Species.

    Science.gov (United States)

    Liang, Guolu; Chen, Hong

    2015-01-01

    This study aims to examine the expected scaling relationships between chromosome size and number across woody species and to clarify the importance of the scaling for the maintenance of chromosome diversity by analyzing the scaling at the inter- & intra-chromosomal level. To achieve for the goals, chromosome trait data were extracted for 191 woody species (including 56 evergreen species and 135 deciduous species) from the available literature. Cross-species analyses revealed a tradeoff among chromosomes between chromosome size and number, demonstrating there is selective mechanism crossing chromosomes among woody species. And the explanations for the result were presented from intra- to inter-chromosome contexts that the scaling may be compromises among scale symmetry, mechanical requirements, and resource allocation across chromosomes. Therein, a 3/4 scaling pattern was observed between total chromosomes and m-chromosomes within nucleus which may imply total chromosomes may evolve from more to less. In addition, the primary evolutionary trend of karyotype and the role of m-chromosomes in the process of karyotype evolution were also discussed.

  13. Adaptive strategies against drought stress of six plant species with different growth forms from karst habitats of southwestern China

    Science.gov (United States)

    Liu, C.; Guo, K.; Liu, Y.

    2012-04-01

    Frequent temporary drought in the rain season, as well as long-term drought in the dry season, is one of the most important factors limiting the survival and growth of plants in the harsh karst habitats of southwestern China. The morphological and physiological responses to drought stress of six native woody plant species were investigated under both temporary and prolonged drought stress. The six plant species included Pyracantha fortuneana (evergreen shrub), Rosa cymosa (deciduous shrub), Cinnamomum bodinieri (evergreen tree), and other three deciduous trees, Broussonetia papyrifera, Platycarya longipes and Pteroceltis tatarinowii. Under severe drought stress, the two shrubs with low leaf area ratio (LAR) maintained higher water status, higher photosynthetic capacity and larger percent biomass increase than the most of the trees, owing to their lower specific leaf area, higher intrinsic water use efficiency and thermal dissipation, and higher capacities of osmotic adjustment and antioxidant protection. The evergreen tree, C. bodinieri, exhibited small decrease of water potential and maintained higher leaf mass ratio (LMR) and LAR than the deciduous species under moderate drought stress, due to the high proline accumulation and high activities of antioxidant enzymes. However, it showed high levels of cellular damages, very low photosynthetic capacity, and sharp decreases of water potential and biomass under severe drought stress. After rewatering, C. bodinieri showed a lower ability to recover from severe drought with the successive repeats of severe drought event. The three deciduous trees developed high root mass ratio for maximizing water uptake, and showed higher LAR and biomass than the two shrubs under well-watered condition. However, drought stress resulted in sharp decreases of biomass in the three deciduous trees, which were attributed to the large drought-induced decreases of LMR, LAR and gas exchange. Under drought conditions, the deciduous trees

  14. Critical zone co-evolution: evidence that weathering and consequent seasonal rock moisture storage leads to a mixed forest canopy of conifer and evergreen broadleaf trees

    Science.gov (United States)

    Oshun, J.; Dietrich, W. E.; Dawson, T. E.; Rempe, D. M.; Fung, I. Y.

    2014-12-01

    Despite recent studies demonstrating the importance of rock moisture as a source of water to vegetation, much remains unknown regarding species-specific and seasonal patterns of water uptake in a Mediterranean climate. Here, we use stable isotopes of water (d18O, dD) to define the isotope composition of water throughout the subsurface critical zone of Rivendell, within the Eel River Critical Zone Observatory. We find that a structured heterogeneity of water isotope composition exists in which bulk saprolite is chronically more negative than bulk soil, and tightly held moisture is more negative than the mobile water that recharges the saturated zone and generates runoff. These moisture reservoirs provide a blueprint from which to measure the seasonal uptake patterns of different species collocated on the site. Douglas-firs use unsaturated saprolite and weathered bedrock moisture (i. e. rock moisture) throughout the year. Contrastingly, hardwood species (madrone, live oak, tanoak) modify their source water depending on which moisture is energetically favorable. Hardwoods use freely mobile water in the wet season, and rely on unsaturated zone soil moisture in the dry season. When soil water tension decreases on the drier south-facing slope, hardwood species use saprolite moisture. Although adjacent hardwoods and Douglas-firs partition water based on matric pull on the north side, there is competition for saprolite moisture in late summer on the south side. These results reveal the eco-hydrological importance of moisture derived from weathered bedrock, and show that the hardwoods have a competitive advantage under the drier conditions predicted in many climate models. Finally, the data emphasize that isotope measurements of all subsurface reservoirs and potential water sources are necessary for a complete and accurate characterization of the eco-hydrological processes within the critical zone.

  15. A comparison of carbon sequestration potential and photosynthetic efficiency in evergreen and deciduous oaks growing in contrasting environments in the Southwest UK

    OpenAIRE

    Carne, Demelza Jane

    2013-01-01

    Global climate change is predicted to alter the weather patterns around the world, as climatic zones shift, forest carbon sequestration projects (e.g. the UK woodland carbon code) need to take into account the specific requirements of planted species. In the UK, oaks are an important charismatic group of trees favoured in recent planting programmes. The English oak (Quercus robur L.), has poor water conservation, but is a major component of natural forests in lowland UK. On the other hand, Ho...

  16. Drought-induced photosynthetic inhibition and autumn recovery in two Mediterranean oak species (Quercus ilex and Quercus suber).

    Science.gov (United States)

    Vaz, M; Pereira, J S; Gazarini, L C; David, T S; David, J S; Rodrigues, A; Maroco, J; Chaves, M M

    2010-08-01

    Responses of leaf water relations and photosynthesis to summer drought and autumn rewetting were studied in two evergreen Mediterranean oak species, Quercus ilex spp. rotundifolia and Quercus suber. The predawn leaf water potential (Ψ(lPD)), stomatal conductance (gs) and photosynthetic rate (A) at ambient conditions were measured seasonally over a 3-year period. We also measured the photosynthetic response to light and to intercellular CO₂ (A/PPFD and A/C(i) response curves) under water stress (summer) and after recovery due to autumn rainfall. Photosynthetic parameters, Vc(max), J(max) and triose phosphate utilization (TPU) rate, were estimated using the Farquhar model. RuBisCo activity, leaf chlorophyll, leaf nitrogen concentration and leaf carbohydrate concentration were also measured. All measurements were performed in the spring leaves of the current year. In both species, the predawn leaf water potential, stomatal conductance and photosynthetic rate peaked in spring, progressively declined throughout the summer and recovered upon autumn rainfall. During the drought period, Q. ilex maintained a higher predawn leaf water potential and stomatal conductance than Q. suber. During this period, we found that photosynthesis was not only limited by stomatal closure, but was also downregulated as a consequence of a decrease in the maximum carboxylation rate (Vc(max)) and the light-saturated rate of photosynthetic electron transport (J(max)) in both species. The Vc(max) and J(max) increased after the first autumnal rains and this increase was related to RuBisCo activity, leaf nitrogen concentration and chlorophyll concentration. In addition, an increase in the TPU rate and in soluble leaf sugar concentration was observed in this period. The results obtained indicate a high resilience of the photosynthetic apparatus to summer drought as well as good recovery in the following autumn rains of these evergreen oak species.

  17. Coarse root spatial distribution determined using a ground-penetrating radar technique in a subtropical evergreen broad-leaved forest, China.

    Science.gov (United States)

    Yan, Hui; Dong, Xinliang; Feng, Gang; Zhang, Shouren; Mucciardi, Anthony

    2013-11-01

    Coarse roots play a critical role in forest ecosystems and both abiotic and biotic factors affect their spatial distribution. To some extent, coarse root density may reflect the quantity of root biomass and biotic competition in forests. However, using traditional methods (e.g., excavation) to study coarse roots is challenging, because those methods are time-consuming and laborious. Furthermore, these destructive methods cannot be repeated in the same forests. Therefore, the discovery of non-destructive methods for root studies will be very significant. In this study, we used a ground-penetrating radar technique to detect the coarse root density of three habitats (ridge, slope and valley) and the dominant tree species (Castanopsis eyrei and Schima superba) in a subtropical forest. We found that (i) the mean of coarse root density for these three habitats was 88.04 roots m(-2), with roots being mainly distributed at depths of 0-40 cm. Coarse root densities were lower in deeper soils and in areas far from the trunk. (ii) Coarse root densities differed significantly among the three habitats studied here with slope habitat having the lowest coarse root density. Compared with S. superba, C. eyrei had more roots distributed in deeper soils. Furthermore, coarse roots with a diameter >3 cm occurred more frequently in the valleys, compared with root densities in ridge and slope habitats, and most coarse roots occurred at soil depths of 20-40 cm. (iii) The coarse root density correlated negatively with tree species richness at soil depths of 40-60 cm. The abundances of the dominant species, such as C. eyrei, Cyclobalanopsis glauca, Pinus massoniana, had significant impacts on coarse root density. (iv) The soil depth of 0-40 cm was the "basic distribution layer" for coarse roots since the majority of coarse roots were found in this soil layer with an average root density of 84.18 roots m(-2), which had no significant linear relationships with topography, tree species richness

  18. Life-history traits predict perennial species response to fire in a desert ecosystem

    Science.gov (United States)

    Shryock, Daniel F.; DeFalco, Lesley A.; Esque, Todd C.

    2014-01-01

    The Mojave Desert of North America has become fire-prone in recent decades due to invasive annual grasses that fuel wildfires following years of high rainfall. Perennial species are poorly adapted to fire in this system, and post-fire shifts in species composition have been substantial but variable across community types. To generalize across a range of conditions, we investigated whether simple life-history traits could predict how species responded to fire. Further, we classified species into plant functional types (PFTs) based on combinations of life-history traits and evaluated whether these groups exhibited a consistent fire-response. Six life-history traits varied significantly between burned and unburned areas in short (up to 4 years) or long-term (up to 52 years) post-fire datasets, including growth form, lifespan, seed size, seed dispersal, height, and leaf longevity. Forbs and grasses consistently increased in abundance after fire, while cacti were reduced and woody species exhibited a variable response. Woody species were classified into three PFTs based on combinations of life-history traits. Species in Group 1 increased in abundance after fire and were characterized by short lifespans, small, wind-dispersed seeds, low height, and deciduous leaves. Species in Group 2 were reduced by fire and distinguished from Group 1 by longer lifespans and evergreen leaves. Group 3 species, which also decreased after fire, were characterized by long lifespans, large non-wind dispersed seeds, and taller heights. Our results show that PFTs based on life-history traits can reliably predict the responses of most species to fire in the Mojave Desert. Dominant, long-lived species of this region possess a combination of traits limiting their ability to recover, presenting a clear example of how a novel disturbance regime may shift selective environmental pressures to favor alternative life-history strategies.

  19. Complete chloroplast genome sequences of two endangered Phoebe (Lauraceae) species.

    Science.gov (United States)

    Li, Yingang; Xu, Wuqin; Zou, Wentao; Jiang, Dongyue; Liu, Xinhong

    2017-09-13

    Phoebe (Lauraceae) comprises of evergreen trees or shrubs with approximately 100 species, distributed in tropical and subtropical Asia and Neotropical America. A total of 34 species and three varieties occur in China. Despite of economic and ecological value, only limited genomic resources are available for this genus. We sequenced the two complete chloroplast (cp) genomes of Phoebe chekiangensis and P. bournei using Illumina sequencing technology via a combined strategy of de novo and reference-guided assembly. We also performed comparative analyses with the cp genomes of P. sheareri and P. sheareri var. oineiensis previously reported. The chloroplast genomes of P. chekiangensis and P. bournei identically contain 112 genes consisting of 78 protein coding genes, 30 tRNA genes, and 4 rRNA genes, with the size of 152,849 and 152,853 bp, respectively. From the two chloroplast genomes, 131 SSRs were identified and 12 different SSRs located in five protein coding genes. The analysis showed the extremely conserved structure of chloroplast genomes with surprisingly little variations at the LSC/IR and SSC/IR boundaries. Moreover, the mean nucleotide diversity was found to be 0.162% for 77 regions, suggesting an extraordinarily low level of sequence divergence. Four highest divergent regions (trnH-psbA, rps14-trnT, petA-psbJ, ccsA-ndhD) with the percentage of nucleotide diversity higher than 0.50% were identified, which had potential use for species identification and phylogenetic studies. This study will facilitate our understanding of population genetics, phylogenetic relationship and plant evolution of Phoebe species.

  20. Growth synchrony between leaves and stems during twig development differs among plant functional types of subtropical rainforest woody species.

    Science.gov (United States)

    Meng, Fengqun; Zhang, Guangfu; Li, Xincheng; Niklas, Karl J; Sun, Shucun

    2015-06-01

    During the development of woody twigs, the growth in leaf may or may not be proportional to the growth in stem. The presence or absence of a synchronicity between these two phenologies may reflect differences in life history adaptive strategies concerning carbon gain. We hypothesized that sun-adapted species are more likely to be less synchronous between growths in total leaf area (TLA) and stem length compared with shade-adapted species, with a bias in growth in stem length, and that shade-adapted species are more likely to be more synchronous between increases in individual leaf area (ILA) (leaf size) and leaf number (LN) during twig development compared with sun-adapted species, giving priority to growth of leaf size. We tested these two hypotheses by recording the phenologies of leaf emergence, leaf expansion and stem elongation during twig development for 19 evergreen woody species (including five shade-adapted understory species, six sun-adapted understory species and eight sun-adapted canopy species) in a subtropical evergreen broad-leaved forest in eastern China. We constructed indices to characterize the synchronicity between TLA and stem length (αLS) and between leaf size and leaf number (αSN) and we derived the α values from logistic functions taking the general form of A = A(max)/[1 + exp(β - αB)] (where A is the TLA or average ILA, B is the corresponding stem length or LN at a specific time, and A(max) is the maximum TLA or the maximum ILA of a twig; the higher the numerical value of α, the less synchronous the corresponding phenologies). Consistent with our hypotheses, sun-adapted species were higher both in α(LS) and α(SN), showing less synchronous patterns in the growths of TLA vs stem length and leaf size vs LN during twig development. Moreover, α(LS) and α(SN) were significantly positively correlated with relative growth rates of LN and leaf size across species, as indicated by both analyses of ordinary regression and

  1. Species composition, Plant Community structure and Natural ...

    African Journals Online (AJOL)

    Bheema

    at good regeneration status. Planning and management of the forest should be assisted by research findings, such as detailed ecological studies in relation to various environmental factors. Keywords: Belete forest, Community structure, Moist Evergreen Montane Forest, Regeneration. 1. INTRODUCTION. Ethiopia has the ...

  2. Ecological Importance of Small-Diameter Trees to the Structure, Diversity and Biomass of a Tropical Evergreen Forest at Rabi, Gabon.

    Directory of Open Access Journals (Sweden)

    Hervé R Memiaghe

    Full Text Available Tropical forests have long been recognized for their biodiversity and ecosystem services. Despite their importance, tropical forests, and particularly those of central Africa, remain understudied. Until recently, most forest inventories in Central Africa have focused on trees ≥10 cm in diameter, even though several studies have shown that small-diameter tree population may be important to demographic rates and nutrient cycling. To determine the ecological importance of small-diameter trees in central African forests, we used data from a 25-ha permanent plot that we established in the rainforest of Gabon to study the diversity and dynamics of these forests. Within the plot, we censused 175,830 trees ≥1 cm dbh from 54 families, 192 genera, and 345 species. Average tree density was 7,026 trees/ha, basal area 31.64 m2/ha, and above-ground biomass 369.40 Mg/ha. Fabaceae, Ebenaceae and Euphorbiaceae were the most important families by basal area, density and above-ground biomass. Small-diameter trees (1 cm ≥ dbh <10 cm comprised 93.7% of the total tree population, 16.5% of basal area, and 4.8% of the above-ground biomass. They also had diversity 18% higher at family level, 34% higher at genus level, and 42% higher at species level than trees ≥10 cm dbh. Although the relative contribution of small-diameter trees to biomass was comparable to other forests globally, their contribution to forest density, and diversity was disproportionately higher. The high levels of diversity within small-diameter classes may give these forests high levels of structural resilience to anthropogenic/natural disturbance and a changing climate.

  3. Ecological Importance of Small-Diameter Trees to the Structure, Diversity and Biomass of a Tropical Evergreen Forest at Rabi, Gabon.

    Science.gov (United States)

    Memiaghe, Hervé R; Lutz, James A; Korte, Lisa; Alonso, Alfonso; Kenfack, David

    2016-01-01

    Tropical forests have long been recognized for their biodiversity and ecosystem services. Despite their importance, tropical forests, and particularly those of central Africa, remain understudied. Until recently, most forest inventories in Central Africa have focused on trees ≥10 cm in diameter, even though several studies have shown that small-diameter tree population may be important to demographic rates and nutrient cycling. To determine the ecological importance of small-diameter trees in central African forests, we used data from a 25-ha permanent plot that we established in the rainforest of Gabon to study the diversity and dynamics of these forests. Within the plot, we censused 175,830 trees ≥1 cm dbh from 54 families, 192 genera, and 345 species. Average tree density was 7,026 trees/ha, basal area 31.64 m2/ha, and above-ground biomass 369.40 Mg/ha. Fabaceae, Ebenaceae and Euphorbiaceae were the most important families by basal area, density and above-ground biomass. Small-diameter trees (1 cm ≥ dbh tree population, 16.5% of basal area, and 4.8% of the above-ground biomass. They also had diversity 18% higher at family level, 34% higher at genus level, and 42% higher at species level than trees ≥10 cm dbh. Although the relative contribution of small-diameter trees to biomass was comparable to other forests globally, their contribution to forest density, and diversity was disproportionately higher. The high levels of diversity within small-diameter classes may give these forests high levels of structural resilience to anthropogenic/natural disturbance and a changing climate.

  4. Responses to changes in Ca2+ supply in two Mediterranean evergreens, Phillyrea latifolia and Pistacia lentiscus, during salinity stress and subsequent relief.

    Science.gov (United States)

    Tattini, Massimiliano; Traversi, Maria Laura

    2008-10-01

    Changes in root-zone Ca(2+) concentration affect a plant's performance under high salinity, an issue poorly investigated for Mediterranean xerophytes, which may suffer from transient root-zone salinity stress in calcareous soils. It was hypothesized that high-Ca(2+) supply may affect differentially the response to salinity stress of species differing in their strategy of Na(+) allocation at organ level. Phillyrea latifolia and Pistacia lentiscus, which have been reported to greatly differ for Na(+) uptake and transport rates to the leaves, were studied. Methods In plants exposed to 0 mM or 200 mM NaCl and supplied with 2.0 mM or 8.0 mM Ca(2+), under 100 % solar irradiance, measurements were conducted of (a) gas exchange, PSII photochemistry and plant growth; (b) water and ionic relations; (c) the activity of superoxide dismutase and the lipid peroxidation; and (d) the concentration of individual polyphenols. Gas exchange and plant growth were also estimated during a period of relief from salinity stress. Key Results The performance of Pistacia lentiscus decreased to a significantly smaller degree than that of Phillyrea latifolia because of high salinity. Ameliorative effects of high-Ca(2+) supply were more evident in Phillyrea latifolia than in Pistacia lentiscus. High-Ca(2+) reduced steeply the Na(+) transport to the leaves in salt-treated Phillyrea latifolia, and allowed a faster recovery of gas exchange and growth rates as compared with low-Ca(2+) plants, during the period of relief from salinity. Salt-induced biochemical adjustments, mostly devoted to counter salt-induced oxidative damage, were greater in Phillyrea latifolia than in Pistacia lentiscus. An increased Ca(2+) : Na(+) ratio may be of greater benefit for Phillyrea latifolia than for Pistacia lentiscus, as in the former, adaptive mechanisms to high root-zone salinity are primarily devoted to restrict the accumulation of potentially toxic ions in sensitive shoot organs.

  5. Robles in Lagunas de Epulauquen, Argentina: previous and recent evidence of their distinctive character

    National Research Council Canada - National Science Library

    Azpilicueta, María M; Pastorino, Mario J; Puntieri, Javier; Barbero, Fernando; Martinez-Meier, Alejandro; Marchelli, Paula; Gallo, Leonardo A

    2014-01-01

    The northernmost ‘robles’ of Argentina, located in Lagunas de Epulauquen (northwest Patagonia), are considered a population of Nothofagus obliqua, even though they differ in some respects from individuals of other populations of the species...

  6. Species-specific effects of woody litter on seedling emergence and growth of herbaceous plants.

    Directory of Open Access Journals (Sweden)

    Kadri Koorem

    Full Text Available The effect of litter on seedling establishment can influence species richness in plant communities. The effect of litter depends on amount, and also on litter type, but relatively little is known about the species-specific effects of litter. We conducted a factorial greenhouse experiment to examine the effect of litter type, using two woody species that commonly co-occur in boreonemoral forest--evergreen spruce (Picea abies, deciduous hazel (Corylus avellana, and a mixture of the two species--and litter amount--shallow (4 mm, deep (12 mm and leachate--on seedling emergence and biomass of three understorey species. The effect of litter amount on seedling emergence was highly dependent on litter type; while spruce needle litter had a significant negative effect that increased with depth, seedling emergence in the presence of hazel broadleaf litter did not differ from control pots containing no litter. Mixed litter of both species also had a negative effect on seedling emergence that was intermediate compared to the single-species treatments. Spruce litter had a marginally positive (shallow or neutral effect (deep on seedling biomass, while hazel and mixed litter treatments had significant positive effects on biomass that increased with depth. We found non-additive effects of litter mixtures on seedling biomass indicating that high quality hazel litter can reduce the negative effects of spruce. Hazel litter does not inhibit seedling emergence; it increases seedling growth, and creates better conditions for seedling growth in mixtures by reducing the suppressive effect of spruce litter, having a positive effect on understorey species richness.

  7. Bud composition, branching patterns and leaf phenology in cerrado woody species.

    Science.gov (United States)

    Damascos, M A; Prado, C H B A; Ronquim, C C

    2005-11-01

    Plants have complex mechanisms of aerial biomass exposition, which depend on bud composition, the period of the year in which shoot extension occurs, branching pattern, foliage persistence, herbivory and environmental conditions. The influence of water availability and temperature on shoot growth, the bud composition, the leaf phenology, and the relationship between partial leaf fall and branching were evaluated over 3 years in Cerrado woody species Bauhinia rufa (BR), Leandra lacunosa (LL) and Miconia albicans (MA). Deciduous BR preformed organs in buds and leaves flush synchronously at the transition from the dry to the wet season. The expansion time of leaves is <1 month. Main shoots (first-order axis, A1 shoots) extended over 30 d and they did not branch. BR budding and foliage unfolds were brought about independently of inter-annual rainfall variations. By contrast, in LL and MA evergreen species, the shoot extension rate and the neoformation of aerial organs depended on rainfall. Leaf emergence was continuous for 2-6 months and lamina expansion took place over 1-4 months. The leaf life span was 5-20 months and the main A1 shoot extension happened over 122-177 d. Both evergreen species allocated biomass to shoots, leaves or flowers continuously during the year, branching in the middle of the wet season to form second-order (A2 shoots) and third-order (A3 shoots) axis in LL and A2 shoots in MA. Partial shed of A1 shoot leaves would facilitate a higher branching intensity A2 shoot production in LL than in MA. MA presented a longer leaf life span, produced a lower percentage of A2 shoots but had a higher meristem persistence on A1 and A2 shoots than LL. It was possible to identify different patterns of aerial growth in Cerrado woody species defined by shoot-linked traits such as branching pattern, bud composition, meristem persistence and leaf phenology. These related traits must be considered over and above leaf deciduousness for searching functional guilds in a

  8. Seedling growth in greenhouse conditions of the forest species Dialium guianense (Aubl. Sandwith

    Directory of Open Access Journals (Sweden)

    Georgina Vargas Simon

    2018-01-01

    Full Text Available Dialium guianense is used for its wood and fruit production, and is a tropical tree species native to evergreen forests. Given the threat these forests face, the purpose of this work was to evaluate the initial growth of the plant under greenhouse conditions, for aiming in the development of propagation programs. Seedlings of the species were transplanted to nursery bags under a completely randomized design and grown for 10 months with an initial population of 200 plants. At the end of the experiment, the shoot and root reached lengths of 32.8 and 28.9 cm, respectively. The average number of composite leaves was 12.3 each with seven leaflets. The average biomass was 2.5 g for the shoot, 1.6 g for roots, and 3.7 g for leaves, with a shoot/root around four. The average relative growth rate (RGR was 15 mg g-1 day-. These characteristics indicate that D. guianense is a late successional species.

  9. Changes in leaf phenology of three European oak species in response to experimental climate change.

    Science.gov (United States)

    Morin, Xavier; Roy, Jacques; Sonié, Laurette; Chuine, Isabelle

    2010-06-01

    *Because the phenology of trees is strongly driven by environmental factors such as temperature, climate change has already altered the vegetative and reproductive phenology of many species, especially in the temperate zone. Here, we aimed to determine whether projected levels of warming for the upcoming decades will lead to linear changes in the phenology of trees or to more complex responses. *We report the results of a 3-yr common garden experiment designed to study the phenological response to artificial climate change, obtained through experimental warming and reduced precipitation, of several populations of three European oaks, two deciduous species (Quercus robur, Quercus pubescens) and one evergreen species (Quercus ilex), in a Mediterranean site. *Experimental warming advanced the seedlings' vegetative phenology, causing a longer growing season and higher mortality. However, the rate of advancement of leaf unfolding date was decreased with increasing temperature. Conversely, soil water content did not affect the phenology of the seedlings or their survival. *Our results show that the phenological response of trees to climate change may be nonlinear, and suggest that predictions of phenological changes in the future should not be built on extrapolations of current observed trends.

  10. Equisetum species show uniform epicuticular wax structures but diverse composition patterns.

    Science.gov (United States)

    Brune, Thomas; Haas, Klaus

    2011-01-01

    Only few data on the epicuticular waxes (EWs) of horsetails are available. This contribution therefore focuses on the wax micromorphology and chemical composition of Equisetum species of the subgenera Equisetum and Hippochaete. Distribution patterns and structural details of EW on the shoots were studied by scanning electron microscopy. After extraction with chloroform, the chemical composition of wax isolates was analysed by gas chromatography. Epicuticular wax crystals were non-oriented platelets or membraneous platelets. They were usually located on subsidiary cells of stomata and adjacent cells. Other parts of the shoots were covered mainly with a smooth wax film or small granules only. The chemical constituents found were alkanes, esters, aldehydes, primary alcohols and free fatty acids in a range of C(20)-C(36) (in esters C(36)-C(56)). All species of the subgenus Hippochaete showed a similar pattern of fractions with high percentages of alkanes and aldehydes, whereas the subgenus Equisetum species had distinctly different wax compositions. Extracts from the internodes-surfaces without well-developed EW crystals and only few stomata-showed the lowest contents of aldehydes. The covering with EW crystals will provide unhindered gas exchange and, combined with intracuticular wax, may prevent excess water loss during winter in the evergreen shoots of the subgenus Hippochaete. The results indicate that the Equisetum wax micromorphology and biosynthesis are comparable to EW of other pteridophyte classes and mosses.

  11. The Complete Chloroplast Genome of Catha edulis: A Comparative Analysis of Genome Features with Related Species

    Directory of Open Access Journals (Sweden)

    Cuihua Gu

    2018-02-01

    Full Text Available Qat (Catha edulis, Celastraceae is a woody evergreen species with great economic and cultural importance. It is cultivated for its stimulant alkaloids cathine and cathinone in East Africa and southwest Arabia. However, genome information, especially DNA sequence resources, for C. edulis are limited, hindering studies regarding interspecific and intraspecific relationships. Herein, the complete chloroplast (cp genome of Catha edulis is reported. This genome is 157,960 bp in length with 37% GC content and is structurally arranged into two 26,577 bp inverted repeats and two single-copy areas. The size of the small single-copy and the large single-copy regions were 18,491 bp and 86,315 bp, respectively. The C. edulis cp genome consists of 129 coding genes including 37 transfer RNA (tRNA genes, 8 ribosomal RNA (rRNA genes, and 84 protein coding genes. For those genes, 112 are single copy genes and 17 genes are duplicated in two inverted regions with seven tRNAs, four rRNAs, and six protein coding genes. The phylogenetic relationships resolved from the cp genome of qat and 32 other species confirms the monophyly of Celastraceae. The cp genomes of C. edulis, Euonymus japonicus and seven Celastraceae species lack the rps16 intron, which indicates an intron loss took place among an ancestor of this family. The cp genome of C. edulis provides a highly valuable genetic resource for further phylogenomic research, barcoding and cp transformation in Celastraceae.

  12. A new species of ant-loving cricket from Mallorca, Balearic Islands, Spain (Orthoptera, Myrmecophilidae

    Directory of Open Access Journals (Sweden)

    Stalling, T.

    2013-12-01

    Full Text Available A new species of ant-loving cricket, Myrmecophilus fuscus sp. n., is described and illustrated, based on individuals collected on the Balearic island of Mallorca, Spain. Lasius lasioides (Emery, 1869 was the host ant species. The habitat was evergreen oak forest. The holotype specimen was deposited in the collection of the Muséum d’Histoire Naturelle de Genève. The species is closely related to Myrmecophilus acervorum (Panzer, [1799] and belongs to the subgenus Myrmecophilus Berthold, 1827.Se describe e ilustra una nueva especie de grillo mirmecófilo, Myrmecophilus fuscus sp. n., procedente de la isla de Mallorca (islas Baleares, España. Lasius lasioides (Emery, 1869 es la especie hospedadora y su hábitat es el bosque perenne de roble. El holotipo se ha depositado en la colección del Muséum d’Histoire Naturelle de Ginebra. La nueva especie está estrechamente relacionada con Myrmecophilus acervorum (Panzer, [1799] y pertenece al subgénero Myrmecophilus Berthold, 1827.

  13. Molecular, morphological and acoustic assessment of the genus Ophryophryne (Anura, Megophryidae) from Langbian Plateau, southern Vietnam, with description of a new species

    Science.gov (United States)

    Jr., Nikolay A. Poyarkov; Duong, Tang Van; Orlov, Nikolai L.; Gogoleva, Svetlana S.; Vassilieva, Anna B.; Nguyen, Luan Thanh; Nguyen, Vu Dang Hoang; Nguyen, Sang Ngoc; Che, Jing; Mahony, Stephen

    2017-01-01

    Abstract Asian Mountain Toads (Ophryophryne) are a poorly known genus of mostly small-sized anurans from southeastern China and Indochina. To shed light on the systematics within this group, the most comprehensive mitochondrial DNA phylogeny for the genus to date is presented, and the taxonomy and biogeography of this group is discussed. Complimented with extensive morphological data (including associated statistical analyses), molecular data indicates that the Langbian Plateau, in the southern Annamite Mountains, Vietnam, is one of the diversity centres of this genus where three often sympatric species of Ophryophryne are found, O. gerti, O. synoria and an undescribed species. To help resolve outstanding taxonomic confusion evident in literature (reviewed herein), an expanded redescription of O. gerti is provided based on the examination of type material, and the distributions of both O. gerti and O. synoria are considerably revised based on new locality records. We provide the first descriptions of male mating calls for all three species, permitting a detailed bioacoustics comparison of the species. We describe the new species from highlands of the northern and eastern Langbian Plateau, and distinguish it from its congeners by a combination of morphological, molecular and acoustic characters. The new species represents one of the smallest known members of the genus Ophryophryne. At present, the new species is known from montane evergreen forest between 700–2200 m a.s.l. We suggest the species should be considered Data Deficient following IUCN’s Red List categories. PMID:28769667

  14. Species-mediated soil moisture availability and patchy establishment of Pseudotsuga menziesii in chaparral.

    Science.gov (United States)

    Dunne, Jennifer A; Parker, V Thomas

    1999-04-01

    The occurrence of mature individuals of Pseudotsuga menziesii in stands of Arctostaphylos species mark the initial stages of mixed evergreen forest invasion into chaparral in central coastal California. We planted two cohorts of P. menziesii seeds at three sites under stands of two Arctostaphylos species and Adenostoma fasciculatum in order to determine whether first-year seedling emergence and survival, particularly during the regular summer drought, underlie the spatial distribution of mature trees observed in chaparral. Regardless of the chaparral species they were planted under, P. menziesii seeds that were not protected from vertebrate predation displayed very little emergence and no survival. In contrast, emergence of P. menziesii that were protected from vertebrate predators was much higher but still did not significantly differ among the three chaparral species. However, survival of protected seedlings under Arctostaphylos glandulosa was much greater than under A. fasciculatum, with intermediate survival under Arctostaphylos montana. While mortality of protected seedlings due to insect herbivory, fungal infection, and disturbance displayed no consistent patterns, summer drought mortality appeared to drive the patterns of survival of P. menziesii under the different chaparral species. These emergence, mortality, and survival data suggest that spatial patterns of P. menziesii recruitment in chaparral are driven by first-year summer drought seedling mortality, but only in years when seeds and seedlings are released from vertebrate predation pressure. Because the first-year drought mortality and survival patterns of P. menziesii seedlings differed strongly depending on the chaparral species, we examined the additional hypothesis that these patterns are associated with differences in the availability of soil moisture under different chaparral species. Both higher survival and lower drought mortality of P. menziesii seedlings were associated with higher soil

  15. The trait contribution to wood decomposition rates of 15 Neotropical tree species.

    Science.gov (United States)

    van Geffen, Koert G; Poorter, Lourens; Sass-Klaassen, Ute; van Logtestijn, Richard S P; Cornelissen, Johannes H C

    2010-12-01

    The decomposition of dead wood is a critical uncertainty in models of the global carbon cycle. Despite this, relatively few studies have focused on dead wood decomposition, with a strong bias to higher latitudes. Especially the effect of interspecific variation in species traits on differences in wood decomposition rates remains unknown. In order to fill these gaps, we applied a novel method to study long-term wood decomposition of 15 tree species in a Bolivian semi-evergreen tropical moist forest. We hypothesized that interspecific differences in species traits are important drivers of variation in wood decomposition rates. Wood decomposition rates (fractional mass loss) varied between 0.01 and 0.31 yr(-1). We measured 10 different chemical, anatomical, and morphological traits for all species. The species' average traits were useful predictors of wood decomposition rates, particularly the average diameter (dbh) of the tree species (R2 = 0.41). Lignin concentration further increased the proportion of explained inter-specific variation in wood decomposition (both negative relations, cumulative R2 = 0.55), although it did not significantly explain variation in wood decomposition rates if considered alone. When dbh values of the actual dead trees sampled for decomposition rate determination were used as a predictor variable, the final model (including dead tree dbh and lignin concentration) explained even more variation in wood decomposition rates (R2 = 0.71), underlining the importance of dbh in wood decomposition. Other traits, including wood density, wood anatomical traits, macronutrient concentrations, and the amount of phenolic extractives could not significantly explain the variation in wood decomposition rates. The surprising results of this multi-species study, in which for the first time a large set of traits is explicitly linked to wood decomposition rates, merits further testing in other forest ecosystems.

  16. Two new giant pill-millipede species of the genus Zoosphaerium endemic to the Bemanevika area in northern Madagascar (Diplopoda, Sphaerotheriida, Arthrosphaeridae).

    Science.gov (United States)

    Sagorny, Christina; Wesener, Thomas

    2017-05-09

    Madagascar is one of the world's most important hotspots of biodiversity and a center for localized endemism. Among the highly endemic faunal elements are the giant pill-millipedes, order Sphaerotheriida, which are severely understudied in Madagascar. Here we provide descriptions of two new species of endemic giant-pill millipedes of the genus Zoosphaerium Pocock, 1895: Zoosphaerium bemanevika n. sp. and Zoosphaerium minutus n. sp.. Zoosphaerium bemanevika n. sp. belongs to the Z. coquerelianum species-group, while Z. minutus n. sp. is not assignable to a species-group. An updated key to the 19 species of the Z. coquerelianum group is provided. Zoosphaerium minutus n. sp. has a body length of island gigantism. The two newly described species are not closely related to one another but each to different species from the Marojejy Mountain and the lowland rainforest of the east coast. Both species occur sympatrically as microendemics in small patches of humid evergreen forest near Bemanevika in northern Madagascar, an only recently protected area that represents a Malagasy center of endemism.

  17. The ghosts of trees past: savanna trees create enduring legacies in plant species composition.

    Science.gov (United States)

    Stahlheber, Karen A; Crispin, Kimberly L; Anton, Cassidy; D'Antonio, Carla M

    2015-09-01

    Isolated trees in savannas worldwide are known to modify their local environment and interact directly with neighboring plants. Less is known about how related tree species differ in their impacts on surrounding communities, how the effects of trees vary between years, and how composition might change following loss of the tree. To address these knowledge gaps, we explored the following questions: How do savanna trees influence the surrounding composition of herbaceous plants? Is the influence of trees consistent across different species and years? How does this change following the death of the tree? We surveyed herbaceous species composition and environmental attributes surrounding living and dead evergreen and deciduous Quercus trees in California (USA) savannas across several years that differed in their total precipitation. Oak trees of all species created distinct, homogenous understory communities dominated by exotic grasses across several sites. The composition of the low-diversity understory communities showed less interannual variation than open grassland, despite a two-fold difference in precipitation between the driest and wettest year. Vegetation composition was correlated with variation in soil properties, which were strongly affected by trees. Oaks also influenced the communities beyond the edge of the crown, but this depended on site and oak species. Low-diversity understory communities persisted up to 43 years following the death of the tree. A gradual decline in the effect of trees on the physical, environment following death did not result in vegetation becoming more similar to open grassland over time. The presence of long-lasting legacies of past tree crowns highlights the difficulty of assigning control of the current distribution of herbaceous species in grassland to their contemporary environment.

  18. Agroforestry Species Switchboard

    DEFF Research Database (Denmark)

    Kindt, R.; John, I.; Ordonez, J.

    2016-01-01

    The current version of the Agroforestry Species Switchboard documents the presence of a total of 26,135 plant species (33,813 species including synonyms) across 19 web-based databases. When available, hyperlinks to information on the selected species in particular databases are provided. In total...

  19. [Effects of extreme drought on plant species in Karst area of Guizhou Province, Southwest China].

    Science.gov (United States)

    Xiong, Hong-Fu; Wang, Shi-Jie; Rong, Li; Cheng, An-Yun; Li, Yang-Bing

    2011-05-01

    Based on the investigation data of damaged vegetations in Karst areas of Guizhou Province during the extreme drought in 2010, an investigation was made on the species composition, floristic composition, life form, leaf characteristics, and environmental conditions of drought-damaged plants at six sampling plots. At these plots, there were 31 plant species drought-damaged, among which, Cunninghamia lanceolata, Celastrus orbiculatus, Rapanea neriifolia, Myrsine semiserrata, Cyclobalanopsis glauca, and Cinnamomum glanduliferum damaged most, and the tropical evergreen arbors with mesophyllous, leathery, and simple leaf suffered more seriously. The damaged plants mainly located on the middle or upper part of steep slopes, and on the thin limestone soils originated from horizontal attitude carbonate rocks. The plants in the microhabitats with soil layer < 30 cm and rock-soil were damaged most, accounting for 87.4% and 40.0% of the total, respectively. It was suggested that the temperate deciduous trees with microphyll could be more planted in Karst areas, and that the microhabitat for the afforestation could be in gully and with thicker soil layer and good site condition.

  20. Exemplifying whole-plant ozone uptake in adult forest trees of contrasting species and site conditions

    Energy Technology Data Exchange (ETDEWEB)

    Nunn, Angela J. [Ecophysiology of Plants, Department of Ecology, Technical University of Muenchen, Am Hochanger 13, D-85354 Freising, Bavaria (Germany)]. E-mail: nunn@wzw.tum.de; Wieser, Gerhard [Federal Research and Training Centre for Forests, Natural Hazards and Landscape, Unit Alpine Timberline Ecophysiology, Rennweg 1, 6020 Innsbruck (Austria); Metzger, Ursula [Ecophysiology of Plants, Department of Ecology, Technical University of Muenchen, Am Hochanger 13, D-85354 Freising, Bavaria (Germany); Loew, Markus [Ecophysiology of Plants, Department of Ecology, Technical University of Muenchen, Am Hochanger 13, D-85354 Freising, Bavaria (Germany); Wipfler, Philip [Forest Yield Science, Technical University of Muenchen, Am Hochanger 13, D-85354 Freising (Germany); Haeberle, Karl-Heinz [Ecophysiology of Plants, Department of Ecology, Technical University of Muenchen, Am Hochanger 13, D-85354 Freising, Bavaria (Germany); Matyssek, Rainer [Ecophysiology of Plants, Department of Ecology, Technical University of Muenchen, Am Hochanger 13, D-85354 Freising, Bavaria (Germany)

    2007-04-15

    Whole-tree O{sub 3} uptake was exemplified for Picea abies, Fagus sylvatica and Larix decidua in stands at high and low altitude and contrasting water availability through sap flow measurement in tree trunks, intrinsically accounting for drought and boundary layer effects on O{sub 3} flux. O{sub 3} uptake of evergreen spruce per unit foliage area was enhanced by 100% at high relative to low elevation, whereas deciduous beech and larch showed similar uptake regardless of altitude. The responsiveness of the canopy conductance to water vapor and, as a consequence, O{sub 3} uptake to soil moisture and air humidity did not differ between species. Unifying findings at the whole-tree level will promote cause-effect based O{sub 3} risk assessment and modeling. - Sap flow-based assessment of whole-tree O{sub 3} uptake reflects similar responsiveness of canopy conductance and O{sub 3} uptake across contrasting tree species and site conditions.

  1. Is there a species spectrum within the world-wide leaf economics spectrum? Major variations in leaf functional traits in the Mediterranean sclerophyll Quercus ilex.

    Science.gov (United States)

    Niinemets, Ulo

    2015-01-01

    The leaf economics spectrum is a general concept describing coordinated variation in foliage structural, chemical and physiological traits across resource gradients. Yet, within this concept,the role of within-species variation, including ecotypic and plastic variation components, has been largely neglected. This study hypothesized that there is a within-species economics spectrum within the general spectrum in the evergreen sclerophyll Quercus ilex which dominates low resource ecosystems over an exceptionally wide range. An extensive database of foliage traits covering the full species range was constructed, and improved filtering algorithms were developed. Standardized data filtering was deemed absolutely essential as additional variation sources can result in trait variation of 10–300%,blurring the broad relationships. Strong trait variation, c. two-fold for most traits to up to almost an order of magnitude, was uncovered.Although the Q. ilex spectrum is part of the general spectrum, within-species trait and climatic relationships in this species partly differed from the overall spectrum. Contrary to world-wide trends, Q. ilex does not necessarily have a low nitrogen content per mass and can increase photosynthetic capacity with increasing foliage robustness. This study argues that the within-species economics spectrum needs to be considered in regional- to biome-level analyses.

  2. Correlations between leaf toughness and phenolics among species in contrasting environments of Australia and New Caledonia

    Science.gov (United States)

    Read, Jennifer; Sanson, Gordon D.; Caldwell, Elizabeth; Clissold, Fiona J.; Chatain, Alex; Peeters, Paula; Lamont, Byron B.; De Garine-Wichatitsky, Michel; Jaffré, Tanguy; Kerr, Stuart

    2009-01-01

    Background and Aims Plants are likely to invest in multiple defences, given the variety of sources of biotic and abiotic damage to which they are exposed. However, little is known about syndromes of defence across plant species and how these differ in contrasting environments. Here an investigation is made into the association between carbon-based chemical and mechanical defences, predicting that species that invest heavily in mechanical defence of leaves will invest less in chemical defence. Methods A combination of published and unpublished data is used to test whether species with tougher leaves have lower concentrations of phenolics, using 125 species from four regions of Australia and the Pacific island of New Caledonia, in evergreen vegetation ranging from temperate shrubland and woodland to tropical shrubland and rainforest. Foliar toughness was measured as work-to-shear and specific work-to-shear (work-to-shear per unit leaf thickness). Phenolics were measured as ‘total phenolics’ and by protein precipitation (an estimate of tannin activity) per leaf dry mass. Key Results Contrary to prediction, phenolic concentrations were not negatively correlated with either measure of leaf toughness when examined across all species, within regions or within any plant community. Instead, measures of toughness (particularly work-to-shear) and phenolics were often positively correlated in shrubland and rainforest (but not dry forest) in New Caledonia, with a similar trend suggested for shrubland in south-western Australia. The common feature of these sites was low concentrations of soil nutrients, with evidence of P limitation. Conclusions Positive correlations between toughness and phenolics in vegetation on infertile soils suggest that additive investment in carbon-based mechanical and chemical defences is advantageous and cost-effective in these nutrient-deficient environments where carbohydrate may be in surplus. PMID:19098067

  3. The effect of altitude, patch size and disturbance on species richness and density of lianas in montane forest patches

    Science.gov (United States)

    Mohandass, Dharmalingam; Campbell, Mason J.; Hughes, Alice C.; Mammides, Christos; Davidar, Priya

    2017-08-01

    The species richness and density of lianas (woody vines) in tropical forests is determined by various abiotic and biotic factors. Factors such as altitude, forest patch size and the degree of forest disturbance are known to exert strong influences on liana species richness and density. We investigated how liana species richness and density were concurrently influenced by altitude (1700-2360 m), forest patch size, forest patch location (edge or interior) and disturbance intensity in the tropical montane evergreen forests, of the Nilgiri and Palni hills, Western Ghats, southern India. All woody lianas (≥1 cm dbh) were enumerated in plots of 30 × 30 m in small, medium and large forest patches, which were located along an altitudinal gradient ranging from 1700 to 2360 m. A total of 1980 individual lianas were recorded, belonging to 45 species, 32 genera and 21 families, from a total sampling area of 13.86 ha (across 154 plots). Liana species richness and density decreased significantly with increasing altitude and increased with increasing forest patch size. Within forest patches, the proportion of forest edge or interior habitat influenced liana distribution and succession especially when compared across the patch size categories. Liana species richness and density also varied along the altitudinal gradient when examined using eco-physiological guilds (i.e. shade tolerance, dispersal mode and climbing mechanism). The species richness and density of lianas within these ecological guilds responded negatively to increasing altitude and positively to increasing patch size and additionally displayed differing sensitivities to forest disturbance. Importantly, the degree of forest disturbance significantly altered the relationship between liana species richness and density to increasing altitude and patches size, and as such is likely the primary influence on liana response to montane forest succession. Our findings suggest that managing forest disturbance in the examined

  4. Regulatory factors in crustacean zooplankton assemblages in mountain lakes of northern Chilean Patagonia (38-41°S: a comparison with Bulgarian counterparts (42°N Factores reguladores en ensambles de crustáceos zooplanctónicos en lagos de montaña del norte de la Patagonia chilena (38-41°S: una comparación con sus contrapartes de Bulgaria (42°N

    Directory of Open Access Journals (Sweden)

    Patricio De los Ríos-Escalante

    2012-07-01

    Full Text Available Chilean Patagonia has protected mountainous areas with evergreen native forests; in which the lakes and rivers, of volcanic or glacial origin, are oligotrophic. In Bulgaria, there are mountainous zones with native forests and associated lakes of volcanic origin. The aim of the present study is to carry out a preliminary comparison of zooplanktonic crustaceans in lake ecosystems associated with native forests of Chilean Patagonia and of Bulgarian mountains. The study revealed that the lakes studied in Chilean Patagonia are associated mainly with Nothofagus forests; they are oligotrophic, with a low number of zooplanktonic crustacean species. Similar results were observed for Bulgarian mountain lakes associated with Fagus forests. A null model analysis of species co-occurrence was applied to the two groups of lakes, and the result revealed the absence of regulatory factors in species associations. These studies agree with similar descriptions of lakes in Andean Patagonia and New Zealand. They highlight the important role of native Nothofagus forests in Argentina and Chile, and of Fagus forests with associated soil properties in Bulgaria, in the oligotrophy of the lakes studied.La Patagonia de Chile tiene una serie de áreas protegidas con bosques nativos perennes asociados a lagos y ríos oligotróficos y de origen glacial. Por otro lado en Bulgaria hay una serie de zonas montañosas con lagos asociados de origen volcánico o glacial. El objetivo del presente trabajo es realizar una primera descripción de especies de crustáceos zooplanctónicos en ecosistemas lacustres asociados a bosques nativos en la Patagonia de Chile y en las montañas de Bulgaria. Los estudios indican que los lagos de la Patagonia de Chile están asociados principalmente con bosques de Nothofagus, mientras que similares resultados fueron observados en lagos de Bulgaria con bosques de Fagus. La regresión lineal entre concentración de clorofila y número de especies para

  5. Endangered Species Act

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The purpose of the Endangered Species Act (ESA) is to protect and recover imperiled species and the ecosystems upon which they depend. The U.S. Fish and Wildlife...

  6. Endangered Species Protection Bulletins

    Science.gov (United States)

    Endangered Species Protection Bulletins set forth geographically specific pesticide use limitations for the protection of threatened and endangered (listed) species and their designated critical habitat. Find out how to get and use Bulletins.

  7. Invasive forest species

    Science.gov (United States)

    Barbara L. Illman

    2006-01-01

    Nonnative organisms that cause a major change to native ecosystems-once called foreign species, biological invasions, alien invasives, exotics, or biohazards–are now generally referred to as invasive species or invasives. invasive species of insects, fungi, plants, fish, and other organisms present a rising threat to natural forest ecosystems worldwide. Invasive...

  8. Species Composition (SC)

    Science.gov (United States)

    John F. Caratti

    2006-01-01

    The FIREMON Species Composition (SC) method is used to provide ocular estimates of cover and height measurements for plant species on a macroplot. The SC method provides plant species composition and coverage estimates to describe a stand or plant community and can be used to document changes over time. It is suited for a wide variety of vegetation types and is...

  9. The Earth's Vanishing Species.

    Science.gov (United States)

    USA Today, 1981

    1981-01-01

    Elaborates on the problem of expanding human activity to the world's plant and animal species. Concludes that preserving an individual species is largely a waste of time and effort and that the best way to protect the most species of plants and animals is to save their environments over large tracts of land. (DB)

  10. Having our yards and sharing them too: the collective effects of yards on native bird species in an urban landscape.

    Science.gov (United States)

    Belaire, J Amy; Whelan, Christopher J; Minor, Emily S

    Residential yards comprise a substantial portion of urban landscapes, and the collective effects of the management of many individual yards may “scale up” to affect urban biodiversity. We conducted bird surveys and social surveys in Chicago-area (Illinois, USA) residential neighborhoods to identify the relative importance of yard design and management activities for native birds. We found that groups of neighboring yards, in the aggregate, were more important for native bird species richness than environmental characteristics at the neighborhood or landscape scale. The ratio of evergreen to deciduous trees in yards and the percentage of yards with trees and plants with fruits or berries were positively associated with native bird species richness, whereas the number of outdoor cats had a negative association. The number of birdfeeders was not an important predictor for native species richness. We also found that migratory birds were observed on transects with more wildlife-friendly features in yards, and nonnative birds were observed on transects with greater numbers of outdoor cats and dogs. Our results highlight the potential importance of residential matrix management as a conservation strategy in urban areas.

  11. Response of the Fine Root Production, Phenology, and Turnover Rate of Six Shrub Species from a Subtropical Forest to a Soil Moisture Gradient and Shading

    Science.gov (United States)

    Fu, X.; Dai, X.; Wang, H.

    2015-12-01

    Knowledge of the fine root dynamics of different life forms in forest ecosystems is critical to understanding how the overall belowground carbon cycling is affected by climate change. However, our current knowledge regarding how endogenous or exogenous factors regulate the root dynamics of understory vegetation is limited. We selected a suite of study sites representing different habitats with gradients of soil moisture and solar radiation (shading or no shading). We assessed the fine root production phenology, the total fine root production, and the turnover among six understory shrub species in a subtropical climate, and examined the responses of the fine root dynamics to gradients in the soil moisture and solar radiation. The shrubs included three evergreen species, Loropetalum chinense, Vaccinium bracteatum, and Adinandra millettii, and three deciduous species, Serissa serissoides, Rubus corchorifolius, and Lespedeza davidii. We observed that variations in the annual fine root production and turnover among species were significant in the deciduous group but not in the evergreen group. Notably, V. bracteatum and S. serissoides presented the greatest responses in terms of root phenology to gradients in the soil moisture and shading: high-moisture habitat led to a decrease and shade led to an increase in fine root production during spring. Species with smaller fine roots of the 1st+2nd-order diameter presented more sensitive responses in terms of fine root phenology to a soil moisture gradient. Species with a higher fine root nitrogen-to -carbon ratio exhibited more sensitive responses in terms of fine root annual production to shading. Soil moisture and shading did not change the annual fine root production as much as the turnover rate. The fine root dynamics of some understory shrubs varied significantly with soil moisture and solar radiation status and may be different from tree species. Our results emphasize the need to study the understory fine root dynamics

  12. Species choice, provenance and species trials among native Brazilian species

    Energy Technology Data Exchange (ETDEWEB)

    Drumond, M.A.

    1982-01-01

    Six papers from the conference are presented. Drumond, M.A., Potential of species native to the semi-arid tropics, 766-781, (Refs. 18), reports on Anadenanthera macrocarpa, Mimosa species, Schinopsis brasiliensis, Spondias tuberosa, Ziziphus joazeiro, Cnidoscolus phyllacanthus, Bursera leptophleos (leptophloeos), Tabebuia impetiginosa, Astronium urundeuva, and Mimosa caesalpinia. Monteiro, R.F.R., Speltz, R.M., Gurgel, J.T. do A.; Silvicultural performance of 24 provenances of Araucaria angustifolia in Parana, 814-824, (Refs. 8). Pires, C.L. da S., Kalil Filho, A.N., Rosa, P.R.F. da, Parente, P.R., Zanatto, A.C.S.; Provenance trials of Cordia alliodora in the State of Sao Paulo, 988-995, (Refs. 9). Nogueira, J.C.B., Siqueira, A.C.M.F., Garrido, M.A.O., Gurgel Garrido, L.M. do A., Rosa, P.R.F., Moraes, J.L. de, Zandarin, M.A., Gurgel Filho, O.A., Trials of some native species in various regions of the State of Sao Paulo, 1051-1063, (Refs. 9) describes Centrolobium tomentosum, Peltophorum dubium, Tabebuia vellosoi, Cariniana legalis, and Balfourodendron riedelianum. Batista, M.P., Borges, J.F., Franco, M.A.B.; Early growth of a native species in comparison with exotics in northeastern Para, Brazil, 1105-1110, (Refs. 3). Jacaranda copaia is compared with Gmelina arborea, Pinus caribaea various hondurensis, Eucalyptus deglupta, and E. urophylla. Lima, P.C.F., Souza, S.M. de, Drumond, M.A.; Trials of native forest species at Petrolina, Pernambuco, 1139-1148, (Refs. 8), deals with Anadenanthera macrocarpa, Piptadenia obliqua, Pithecellobium foliolosum, Astronium urundeuva, Schinopsis brasiliensis, Cassia excelsa, Caesalpinia pyramidalis, Parkia platycephala, Pseudobombax simplicifolium, Tabebuia impetiginosa, Caesalpinia ferrea, and Aspidosperma pyrifolium. 18 references.

  13. Species-Specific Effects on Throughfall Kinetic Energy in Subtropical Forest Plantations Are Related to Leaf Traits and Tree Architecture.

    Science.gov (United States)

    Goebes, Philipp; Bruelheide, Helge; Härdtle, Werner; Kröber, Wenzel; Kühn, Peter; Li, Ying; Seitz, Steffen; von Oheimb, Goddert; Scholten, Thomas

    2015-01-01

    Soil erosion is a key threat to many ecosystems, especially in subtropical China where high erosion rates occur. While the mechanisms that induce soil erosion on agricultural land are well understood, soil erosion processes in forests have rarely been studied. Throughfall kinetic energy (TKE) is influenced in manifold ways and often determined by the tree's leaf and architectural traits. We investigated the role of species identity in mono-specific stands on TKE by asking to what extent TKE is species-specific and which leaf and architectural traits account for variation in TKE. We measured TKE of 11 different tree species planted in monocultures in a biodiversity-ecosystem-functioning experiment in subtropical China, using sand-filled splash cups during five natural rainfall events in summer 2013. In addition, 14 leaf and tree architectural traits were measured and linked to TKE. Our results showed that TKE was highly species-specific. Highest TKE was found below Choerospondias axillaris and Sapindus saponaria, while Schima superba showed lowest TKE. These species-specific effects were mediated by leaf habit, leaf area (LA), leaf pinnation, leaf margin, stem diameter at ground level (GD), crown base height (CBH), tree height, number of branches and leaf area index (LAI) as biotic factors and throughfall as abiotic factor. Among these, leaf habit, tree height and LA showed the highest effect sizes on TKE and can be considered as major drivers of TKE. TKE was positively influenced by LA, GD, CBH, tree height, LAI, and throughfall amount while it was negatively influenced by the number of branches. TKE was lower in evergreen, simple leaved and dentate leaved than in deciduous, pinnated or entire leaved species. Our results clearly showed that soil erosion in forest plantations can be mitigated by the appropriate choice of tree species.

  14. Species-Specific Effects on Throughfall Kinetic Energy in Subtropical Forest Plantations Are Related to Leaf Traits and Tree Architecture

    Science.gov (United States)

    Bruelheide, Helge; Härdtle, Werner; Kröber, Wenzel; Li, Ying; von Oheimb, Goddert

    2015-01-01

    Soil erosion is a key threat to many ecosystems, especially in subtropical China where high erosion rates occur. While the mechanisms that induce soil erosion on agricultural land are well understood, soil erosion processes in forests have rarely been studied. Throughfall kinetic energy (TKE) is influenced in manifold ways and often determined by the tree’s leaf and architectural traits. We investigated the role of species identity in mono-specific stands on TKE by asking to what extent TKE is species-specific and which leaf and architectural traits account for variation in TKE. We measured TKE of 11 different tree species planted in monocultures in a biodiversity-ecosystem-functioning experiment in subtropical China, using sand-filled splash cups during five natural rainfall events in summer 2013. In addition, 14 leaf and tree architectural traits were measured and linked to TKE. Our results showed that TKE was highly species-specific. Highest TKE was found below Choerospondias axillaris and Sapindus saponaria, while Schima superba showed lowest TKE. These species-specific effects were mediated by leaf habit, leaf area (LA), leaf pinnation, leaf margin, stem diameter at ground level (GD), crown base height (CBH), tree height, number of branches and leaf area index (LAI) as biotic factors and throughfall as abiotic factor. Among these, leaf habit, tree height and LA showed the highest effect sizes on TKE and can be considered as major drivers of TKE. TKE was positively influenced by LA, GD, CBH, tree height, LAI, and throughfall amount while it was negatively influenced by the number of branches. TKE was lower in evergreen, simple leaved and dentate leaved than in deciduous, pinnated or entire leaved species. Our results clearly showed that soil erosion in forest plantations can be mitigated by the appropriate choice of tree species. PMID:26079260

  15. Species-Specific Effects on Throughfall Kinetic Energy in Subtropical Forest Plantations Are Related to Leaf Traits and Tree Architecture.

    Directory of Open Access Journals (Sweden)

    Philipp Goebes

    Full Text Available Soil erosion is a key threat to many ecosystems, especially in subtropical China where high erosion rates occur. While the mechanisms that induce soil erosion on agricultural land are well understood, soil erosion processes in forests have rarely been studied. Throughfall kinetic energy (TKE is influenced in manifold ways and often determined by the tree's leaf and architectural traits. We investigated the role of species identity in mono-specific stands on TKE by asking to what extent TKE is species-specific and which leaf and architectural traits account for variation in TKE. We measured TKE of 11 different tree species planted in monocultures in a biodiversity-ecosystem-functioning experiment in subtropical China, using sand-filled splash cups during five natural rainfall events in summer 2013. In addition, 14 leaf and tree architectural traits were measured and linked to TKE. Our results showed that TKE was highly species-specific. Highest TKE was found below Choerospondias axillaris and Sapindus saponaria, while Schima superba showed lowest TKE. These species-specific effects were mediated by leaf habit, leaf area (LA, leaf pinnation, leaf margin, stem diameter at ground level (GD, crown base height (CBH, tree height, number of branches and leaf area index (LAI as biotic factors and throughfall as abiotic factor. Among these, leaf habit, tree height and LA showed the highest effect sizes on TKE and can be considered as major drivers of TKE. TKE was positively influenced by LA, GD, CBH, tree height, LAI, and throughfall amount while it was negatively influenced by the number of branches. TKE was lower in evergreen, simple leaved and dentate leaved than in deciduous, pinnated or entire leaved species. Our results clearly showed that soil erosion in forest plantations can be mitigated by the appropriate choice of tree species.

  16. Soil microbial biomass under different management and tillage systems of permanent intercropped cover species in an orange orchard

    Directory of Open Access Journals (Sweden)

    Elcio Liborio Balota

    2011-12-01

    Full Text Available To mitigate soil erosion and enhance soil fertility in orange plantations, the permanent protection of the inter-rows by cover species has been suggested. The objective of this study was to evaluate alterations in the microbial biomass, due to different soil tillage systems and intercropped cover species between rows of orange trees. The soil of the experimental area previously used as pasture (Brachiaria humidicola was an Ultisol (Typic Paleudult originating from Caiuá sandstone in the northwestern part of the State of Paraná, Brazil. Two soil tillage systems were evaluated: conventional tillage (CT in the entire area and strip tillage (ST (strip width 2 m, in combination with different ground cover management systems. The citrus cultivar 'Pera' orange (Citrus sinensis grafted onto 'Rangpur' lime rootstock was used. Soil samples were collected after five years of treatment from a depth of 0-15 cm, under the tree canopy and in the inter-row, in the following treatments: (1 CT and an annual cover crop with the leguminous species Calopogonium mucunoides; (2 CT and a perennial cover crop with the leguminous peanut Arachis pintoi; (3 CT and an evergreen cover crop with Bahiagrass Paspalum notatum; (4 CT and a cover crop with spontaneous Brachiaria humidicola grass vegetation; and (5 ST and maintenance of the remaining grass (pasture of Brachiaria humidicola. Soil tillage and the different cover species influenced the microbial biomass, both under the tree canopy and in the inter-row. The cultivation of brachiaria increased C and N in the microbial biomass, while bahiagrass increased P in the microbial biomass. The soil microbial biomass was enriched in N and P by the presence of ground cover species and according to the soil P content. The grass species increased C, N and P in the soil microbial biomass from the inter-row more than leguminous species.

  17. Documenting biogeographical patterns of African timber species using herbarium records: a conservation perspective based on native trees from Angola.

    Science.gov (United States)

    Romeiras, Maria M; Figueira, Rui; Duarte, Maria Cristina; Beja, Pedro; Darbyshire, Iain

    2014-01-01

    In many tropical regions the development of informed conservation strategies is hindered by a dearth of biodiversity information. Biological collections can help to overcome this problem, by providing baseline information to guide research and conservation efforts. This study focuses on the timber trees of Angola, combining herbarium (2670 records) and bibliographic data to identify the main timber species, document biogeographic patterns and identify conservation priorities. The study recognized 18 key species, most of which are threatened or near-threatened globally, or lack formal conservation assessments. Biogeographical analysis reveals three groups of species associated with the enclave of Cabinda and northwest Angola, which occur primarily in Guineo-Congolian rainforests, and evergreen forests and woodlands. The fourth group is widespread across the country, and is mostly associated with dry forests. There is little correspondence between the spatial pattern of species groups and the ecoregions adopted by WWF, suggesting that these may not provide an adequate basis for conservation planning for Angolan timber trees. Eight of the species evaluated should be given high conservation priority since they are of global conservation concern, they have very restricted distributions in Angola, their historical collection localities are largely outside protected areas and they may be under increasing logging pressure. High conservation priority was also attributed to another three species that have a large proportion of their global range concentrated in Angola and that occur in dry forests where deforestation rates are high. Our results suggest that timber tree species in Angola may be under increasing risk, thus calling for efforts to promote their conservation and sustainable exploitation. The study also highlights the importance of studying historic herbarium collections in poorly explored regions of the tropics, though new field surveys remain a priority to

  18. Rapidly growing tropical trees mobilize remarkable amounts of nitrogen, in ways that differ surprisingly among species.

    Science.gov (United States)

    Russell, Ann E; Raich, James W

    2012-06-26

    Fast-growing forests such as tropical secondary forests can accumulate large amounts of carbon (C), and thereby play an important role in the atmospheric CO(2) balance. Because nitrogen (N) cycling is inextricably linked with C cycling, the question becomes: Where does the N come from to match high rates of C accumulation? In unique experimental 16-y-old plantations established in abandoned pasture in lowland Costa Rica, we used a mass-balance approach to quantify N accumulation in vegetation, identify sources of N, and evaluate differences among tree species in N cycling. The replicated design contained four broad-leaved evergreen tree species growing under similar environmental conditions. Nitrogen uptake was rapid, reaching 409 (± 30) kg · ha(-1) · y(-1), double the rate reported from a Puerto Rican forest and greater than four times that observed at Hubbard Brook Forest (New Hampshire, USA). Nitrogen amassed in vegetation was 874 (± 176) kg · ha(-1), whereas net losses of soil N (0-100 cm) varied from 217 (±146) to 3,354 (± 915) kg · ha(-1) (P = 0.018) over 16 y. Soil C:N, δ(13)C values, and N budgets indicated that soil was the main source of biomass N. In Vochysia guatemalensis, however, N fixation contributed >60 kg · ha(-1) · y(-1). All species apparently promoted soil N turnover, such that the soil N mean residence time was 32-54 y, an order of magnitude lower than the global mean. High rates of N uptake were associated with substantial N losses in three of the species, in which an average of 1.6 g N was lost for every gram of N accumulated in biomass.

  19. Capparis Cleghornii Dunn, a species from Southern India (Capparaceae)

    NARCIS (Netherlands)

    Rao, Rolla S.; Raghavan, R. Sundara

    1964-01-01

    Among recent collections from the evergreen forests of Mysore State in southern India, material was found of Capparis cleghornii Dunn which had only been known from the original collection made by Cleghorn in 1846 and from a Stocks specimen from “Kanara”. Further scrutiny of fresh collections from

  20. Support your local species

    DEFF Research Database (Denmark)

    Stärk, Johanna

    Nearly a quarter of all animal species within the European Union are threatened with extinction. Protecting many of these species will require the full spectrum of conservation actions from in-situ to ex-situ management. Holding an estimated 44% of EU Red Listed terrestrial vertebrates, zoos hereby...... play an important role in protecting local species. However, outcomes of conservation actions are often highly uncertain and if European zoos want to support the conservation of threatened species, they are faced with the question of which species to target first and which conservation strategy...... to choose. Current decision-making in resource allocation and conservation planning is often, as in many other disciplines, based on little scientific ground. Here, we propose a Decision Analysis framework to support the Ex-situ guidelines of the Species Survival Commission of the IUCN. In which we assessed...

  1. A novel method of measuring leaf epidermis and mesophyll stiffness shows the ubiquitous nature of the sandwich structure of leaf laminas in broad-leaved angiosperm species.

    Science.gov (United States)

    Onoda, Yusuke; Schieving, Feike; Anten, Niels P R

    2015-05-01

    Plant leaves commonly exhibit a thin, flat structure that facilitates a high light interception per unit mass, but may increase risks of mechanical failure when subjected to gravity, wind and herbivory as well as other stresses. Leaf laminas are composed of thin epidermis layers and thicker intervening mesophyll layers, which resemble a composite material, i.e. sandwich structure, used in engineering constructions (e.g. airplane wings) where high bending stiffness with minimum weight is important. Yet, to what extent leaf laminas are mechanically designed and behave as a sandwich structure remains unclear. To resolve this issue, we developed and applied a novel method to estimate stiffness of epidermis- and mesophyll layers without separating the layers. Across a phylogenetically diverse range of 36 angiosperm species, the estimated Young's moduli (a measure of stiffness) of mesophyll layers were much lower than those of the epidermis layers, indicating that leaf laminas behaved similarly to efficient sandwich structures. The stiffness of epidermis layers was higher in evergreen species than in deciduous species, and strongly associated with cuticle thickness. The ubiquitous nature of sandwich structures in leaves across studied species suggests that the sandwich structure has evolutionary advantages as it enables leaves to be simultaneously thin and flat, efficiently capturing light and maintaining mechanical stability under various stresses. © The Author 2015. Published by Oxford University Press on behalf of the Society for Experimental Biology.

  2. A new polytypic species of yellow-shouldered bats, genus Sturnira (Mammalia: Chiroptera: Phyllostomidae), from the Andean and coastal mountain systems of Venezuela and Colombia.

    Science.gov (United States)

    Molinari, Jesús; Bustos, Xiomar E; Burneo, Santiago F; Camacho, M Alejandra; Moreno, S Andrea; Fermín, Gustavo

    2017-03-13

    Sturnira is the most speciose genus of New World leaf-nosed bats (Phyllostomidae). We name Sturnira adrianae, new species. This taxon is born polytypic, divided into a larger subspecies (S. a. adrianae) widespread in the mountains of northern and western Venezuela, and northern Colombia, and a smaller subspecies (S. a. caripana) endemic to the mountains of northeastern Venezuela. The new species inhabits evergreen, deciduous, and cloud forests at mainly medium (1000-2000 m) elevations. It has long been confused with S. ludovici, but it is more closely related to S. oporaphilum. It can be distinguished from other species of Sturnira by genetic data, and based on discrete and continuously varying characters. Within the genus, the new species belongs to a clade that also includes S. oporaphilum, S. ludovici, S. hondurensis, and S. burtonlimi. The larger new subspecies is the largest member of this clade. The two new subspecies are the most sexually dimorphic members of this clade. The smaller new subspecies is restricted to small mountain systems undergoing severe deforestation processes, therefore can be assigned to the Vulnerable (VU) conservation category of the International Union for Conservation of Nature (IUCN).

  3. The Origin of Species

    NARCIS (Netherlands)

    Darwin, Charles

    2005-01-01

    In The Origin of Species Darwin outlined his theory of evolution, which proposed that species had been evolving and differentiating over time under the influence of natural selection. On its publication it became hugely influential, bringing about a seismic shift in the scientific view of humanitys

  4. (WF n ) species

    Indian Academy of Sciences (India)

    Abstract. The present work deals with a systematic study on WFn species using ab initio density functional method. The geometrical features related to the equilibrium structures of WFn species up to n = 5 are high- lighted and the effect of addition as well as removal of an electron is discussed. The chemical stability of.

  5. Arctic species resilience

    DEFF Research Database (Denmark)

    Mortensen, Lars O.; Forchhammer, Mads C.; Jeppesen, Erik

    the predicted increase in climate variability. Whereas species may show relatively high phenological resilience to climate change per se, the resilience of systems may be more constrained by the inherent dependence through consumer-resource interactions across trophic levels. During the last 15 years...... and resources. This poster will present the conceptual framework for this project focusing on species resilience....

  6. Subtle Ecological Gradient in the Tropics Triggers High Species-Turnover in a Local Geographical Scale.

    Directory of Open Access Journals (Sweden)

    Dinh T Nguyen

    Full Text Available Our perception of diversity, including both alpha- and beta-diversity components, depends on spatial scale. Studies of spatial variation of the latter are just starting, with a paucity of research on beta-diversity patterns at smaller scales. Understanding these patterns and the processes shaping the distribution of diversity is critical to describe this diversity, but it is paramount in conservation too. Here, we investigate the diversity and structure of a tropical community of herbivorous beetles at a reduced local scale of some 10 km2, evaluating the effect of a small, gradual ecological change on this structure. We sampled leaf beetles in the Núi Chúa National Park (S Vietnam, studying changes in alpha- and beta-diversity across an elevation gradient up to 500 m, encompassing the ecotone between critically endangered lowland dry deciduous forest and mixed evergreen forest at higher elevations. Leaf beetle diversity was assessed using several molecular tree-based species delimitation approaches (with mtDNA cox1 data, species richness using rarefaction and incidence-based diversity indexes, and beta-diversity was investigated decomposing the contribution of species turnover and nestedness. We documented 155 species in the area explored and species-richness estimates 1.5-2.0x higher. Species diversity was similar in both forest types and changes in alpha-diversity along the elevation gradient showed an expected local increase of diversity in the ecotone. Beta-diversity was high among forest paths (average Sørensen's dissimilarity = 0.694 and, tentatively fixing at 300 m the boundary between otherwise continuous biomes, demonstrated similarly high beta-diversity (Sørensen's dissimilarity = 0.581, with samples clustering according to biome/elevation. Highly relevant considering the local scale of the study, beta-diversity had a high contribution of species replacement among locales (54.8% and between biomes (79.6%, suggesting environmental

  7. Subtle Ecological Gradient in the Tropics Triggers High Species-Turnover in a Local Geographical Scale.

    Science.gov (United States)

    Nguyen, Dinh T; Gómez-Zurita, Jesús

    2016-01-01

    Our perception of diversity, including both alpha- and beta-diversity components, depends on spatial scale. Studies of spatial variation of the latter are just starting, with a paucity of research on beta-diversity patterns at smaller scales. Understanding these patterns and the processes shaping the distribution of diversity is critical to describe this diversity, but it is paramount in conservation too. Here, we investigate the diversity and structure of a tropical community of herbivorous beetles at a reduced local scale of some 10 km2, evaluating the effect of a small, gradual ecological change on this structure. We sampled leaf beetles in the Núi Chúa National Park (S Vietnam), studying changes in alpha- and beta-diversity across an elevation gradient up to 500 m, encompassing the ecotone between critically endangered lowland dry deciduous forest and mixed evergreen forest at higher elevations. Leaf beetle diversity was assessed using several molecular tree-based species delimitation approaches (with mtDNA cox1 data), species richness using rarefaction and incidence-based diversity indexes, and beta-diversity was investigated decomposing the contribution of species turnover and nestedness. We documented 155 species in the area explored and species-richness estimates 1.5-2.0x higher. Species diversity was similar in both forest types and changes in alpha-diversity along the elevation gradient showed an expected local increase of diversity in the ecotone. Beta-diversity was high among forest paths (average Sørensen's dissimilarity = 0.694) and, tentatively fixing at 300 m the boundary between otherwise continuous biomes, demonstrated similarly high beta-diversity (Sørensen's dissimilarity = 0.581), with samples clustering according to biome/elevation. Highly relevant considering the local scale of the study, beta-diversity had a high contribution of species replacement among locales (54.8%) and between biomes (79.6%), suggesting environmental heterogeneity

  8. Sympatric parallel diversification of major oak clades in the Americas and the origins of Mexican species diversity.

    Science.gov (United States)

    Hipp, Andrew L; Manos, Paul S; González-Rodríguez, Antonio; Hahn, Marlene; Kaproth, Matthew; McVay, John D; Avalos, Susana Valencia; Cavender-Bares, Jeannine

    2017-09-18

    Oaks (Quercus, Fagaceae) are the dominant tree genus of North America in species number and biomass, and Mexico is a global center of oak diversity. Understanding the origins of oak diversity is key to understanding biodiversity of northern temperate forests. A phylogenetic study of biogeography, niche evolution and diversification patterns in Quercus was performed using 300 samples, 146 species. Next-generation sequencing data were generated using the restriction-site associated DNA (RAD-seq) method. A time-calibrated maximum likelihood phylogeny was inferred and analyzed with bioclimatic, soils, and leaf habit data to reconstruct the biogeographic and evolutionary history of the American oaks. Our highly resolved phylogeny demonstrates sympatric parallel diversification in climatic niche, leaf habit, and diversification rates. The two major American oak clades arose in what is now the boreal zone and radiated, in parallel, from eastern North America into Mexico and Central America. Oaks adapted rapidly to niche transitions. The Mexican oaks are particularly numerous, not because Mexico is a center of origin, but because of high rates of lineage diversification associated with high rates of evolution along moisture gradients and between the evergreen and deciduous leaf habits. Sympatric parallel diversification in the oaks has shaped the diversity of North American forests. © 2017 The Authors. New Phytologist © 2017 New Phytologist Trust.

  9. Functional indicators of response mechanisms to nitrogen deposition, ozone, and their interaction in two Mediterranean tree species.

    Directory of Open Access Journals (Sweden)

    Lina Fusaro

    Full Text Available The effects of nitrogen (N deposition, tropospheric ozone (O3 and their interaction were investigated in two Mediterranean tree species, Fraxinus ornus L. (deciduous and Quercus ilex L. (evergreen, having different leaf habits and resource use strategies. An experiment was conducted under controlled condition to analyse how nitrogen deposition affects the ecophysiological and biochemical traits, and to explore how the nitrogen-induced changes influence the response to O3. For both factors we selected realistic exposures (20 kg N ha-1 yr-1 and 80 ppb h for nitrogen and O3, respectively, in order to elucidate the mechanisms implemented by the plants. Nitrogen addition resulted in higher nitrogen concentration at the leaf level in F. ornus, whereas a slight increase was detected in Q. ilex. Nitrogen enhanced the maximum rate of assimilation and ribulose 1,5-bisphosphate regeneration in both species, whereas it influenced the light harvesting complex only in the deciduous F. ornus that was also affected by O3 (reduced assimilation rate and accelerated senescence-related processes. Conversely, Q. ilex developed an avoidance mechanism to cope with O3, confirming a substantial O3 tolerance of this species. Nitrogen seemed to ameliorate the harmful effects of O3 in F. ornus: the hypothesized mechanism of action involved the production of nitrogen oxide as the first antioxidant barrier, followed by enzymatic antioxidant response. In Q. ilex, the interaction was not detected on gas exchange and photosystem functionality; however, in this species, nitrogen might stimulate an alternative antioxidant response such as the emission of volatile organic compounds. Antioxidant enzyme activity was lower in plants treated with both O3 and nitrogen even though reactive oxygen species production did not differ between the treatments.

  10. Functional indicators of response mechanisms to nitrogen deposition, ozone, and their interaction in two Mediterranean tree species.

    Science.gov (United States)

    Fusaro, Lina; Palma, Adriano; Salvatori, Elisabetta; Basile, Adriana; Maresca, Viviana; Asadi Karam, Elham; Manes, Fausto

    2017-01-01

    The effects of nitrogen (N) deposition, tropospheric ozone (O3) and their interaction were investigated in two Mediterranean tree species, Fraxinus ornus L. (deciduous) and Quercus ilex L. (evergreen), having different leaf habits and resource use strategies. An experiment was conducted under controlled condition to analyse how nitrogen deposition affects the ecophysiological and biochemical traits, and to explore how the nitrogen-induced changes influence the response to O3. For both factors we selected realistic exposures (20 kg N ha-1 yr-1 and 80 ppb h for nitrogen and O3, respectively), in order to elucidate the mechanisms implemented by the plants. Nitrogen addition resulted in higher nitrogen concentration at the leaf level in F. ornus, whereas a slight increase was detected in Q. ilex. Nitrogen enhanced the maximum rate of assimilation and ribulose 1,5-bisphosphate regeneration in both species, whereas it influenced the light harvesting complex only in the deciduous F. ornus that was also affected by O3 (reduced assimilation rate and accelerated senescence-related processes). Conversely, Q. ilex developed an avoidance mechanism to cope with O3, confirming a substantial O3 tolerance of this species. Nitrogen seemed to ameliorate the harmful effects of O3 in F. ornus: the hypothesized mechanism of action involved the production of nitrogen oxide as the first antioxidant barrier, followed by enzymatic antioxidant response. In Q. ilex, the interaction was not detected on gas exchange and photosystem functionality; however, in this species, nitrogen might stimulate an alternative antioxidant response such as the emission of volatile organic compounds. Antioxidant enzyme activity was lower in plants treated with both O3 and nitrogen even though reactive oxygen species production did not differ between the treatments.

  11. Extragastric Helicobacter species

    DEFF Research Database (Denmark)

    On, Stephen L.W.; Hynes, S.; Wadstrom, T.

    2002-01-01

    The genus Helicobacter has expanded at a rapid pace and no fewer than 31 species have been named since the proposal of the genus in 1989. Of these 31 species, 22 are principally associated with extragastric niches and there is increasing interest in the role of these taxa in diseases of humans...... and animals. Substantial evidence attests to certain species playing a role in the pathogenesis of enteric, hepatic and biliary disorders and some taxa demonstrate zoonotic potential. The importance of extragastric Helicobacters is likely to be an important topic for research in the near future. Here...

  12. Dynamic origin of species

    OpenAIRE

    Sadovsky, Michael G.

    2008-01-01

    A simple model of species origin resulted from dynamic features of a population, solely, is developed. The model is based on the evolution optimality in space distribution, and the selection is gone over the mobility. Some biological issues are discussed.

  13. Fire Management Species Profiles

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — The objective of the Fire Management Species Profile project is to identify habitat management objectives that are specific, measurable, achievable, clearly...

  14. Hierarchical species distribution models

    Science.gov (United States)

    Hefley, Trevor J.; Hooten, Mevin B.

    2016-01-01

    Determining the distribution pattern of a species is important to increase scientific knowledge, inform management decisions, and conserve biodiversity. To infer spatial and temporal patterns, species distribution models have been developed for use with many sampling designs and types of data. Recently, it has been shown that count, presence-absence, and presence-only data can be conceptualized as arising from a point process distribution. Therefore, it is important to understand properties of the point process distribution. We examine how the hierarchical species distribution modeling framework has been used to incorporate a wide array of regression and theory-based components while accounting for the data collection process and making use of auxiliary information. The hierarchical modeling framework allows us to demonstrate how several commonly used species distribution models can be derived from the point process distribution, highlight areas of potential overlap between different models, and suggest areas where further research is needed.

  15. Threatened & Endangered Species Occurrences

    Data.gov (United States)

    Kansas Data Access and Support Center — The database consists of a single statewide coverage of location records for 54 species contained in the Kansas Natural Heritage Inventory database of the Kansas...

  16. Endangered Species: Pesticide Restrictions

    Science.gov (United States)

    Our goal is to protect threatened and endangered species and their habitats, without placing unnecessary burden on agriculture and pesticide users. Pesticide limitations are developed to ensure safe use of pesticides in order to meet this goal.

  17. The species in primatology.

    Science.gov (United States)

    Groves, Colin

    2014-01-01

    Biologists of the late eighteenth and early nineteenth centuries all bandied about the term "species," but very rarely actually said what they meant by it. Often, however, one can get inside their thinking by piecing together some of their remarks. One of the most nearly explicit-appropriately, for the man who wrote a book called The Origin of Species - was Charles Darwin: "Practically, when a naturalist can unite two forms together by others having intermediate characters, he treats the one as a variety of the other… He later translated this into evolutionary terms: "Hereafter, we shall be compelled to acknowledge that the only distinction between species and well-marked varieties is, that the latter are known, or believed, to be connected at the present day by intermediate gradations, whereas species were formerly thus connected"(1:484-5.) Copyright © 2014 Wiley Periodicals, Inc.

  18. Sub specie aeternitatis

    Directory of Open Access Journals (Sweden)

    Laura Gioeni

    2012-10-01

    Full Text Available Per delineare il rapporto tra etica ed estetica nell'architettura e rispondere alla domanda principale «che cosa è o dovrebbe essere un buon architetto?», il saggio discute la tesi di Wittgenstein secondo cui «l'opera d'arte è l'oggetto visto sub specie aeternitatis e la vita buona è il mondo visto sub specie aeternitatis. Questa è la connessione tra arte ed etica».

  19. Genomic definition of species

    Energy Technology Data Exchange (ETDEWEB)

    Crkvenjakov, R.; Drmanac, R.

    1991-07-01

    The subject of this paper is the definition of species based on the assumption that genome is the fundamental level for the origin and maintenance of biological diversity. For this view to be logically consistent it is necessary to assume the existence and operation of the new law which we call genome law. For this reason the genome law is included in the explanation of species phenomenon presented here even if its precise formulation and elaboration are left for the future. The intellectual underpinnings of this definition can be traced to Goldschmidt. We wish to explore some philosophical aspects of the definition of species in terms of the genome. The point of proposing the definition on these grounds is that any real advance in evolutionary theory has to be correct in both its philosophy and its science.

  20. Bounding Species Distribution Models

    Science.gov (United States)

    Stohlgren, Thomas J.; Jarnevich, Cahterine S.; Morisette, Jeffrey T.; Esaias, Wayne E.

    2011-01-01

    Species distribution models are increasing in popularity for mapping suitable habitat for species of management concern. Many investigators now recognize that extrapolations of these models with geographic information systems (GIS) might be sensitive to the environmental bounds of the data used in their development, yet there is no recommended best practice for "clamping" model extrapolations. We relied on two commonly used modeling approaches: classification and regression tree (CART) and maximum entropy (Maxent) models, and we tested a simple alteration of the model extrapolations, bounding extrapolations to the maximum and minimum values of primary environmental predictors, to provide a more realistic map of suitable habitat of hybridized Africanized honey bees in the southwestern United States. Findings suggest that multiple models of bounding, and the most conservative bounding of species distribution models, like those presented here, should probably replace the unbounded or loosely bounded techniques currently used [Current Zoology 57 (5): 642-647, 2011].

  1. Aquatic Nuisance Species Locator

    Science.gov (United States)

    Data in this map has been collected by the United States Geological Survey's Nonindigenous Aquatic Species program located in Gainesville, Florida (http://nas.er.usgs.gov/default.aspx). This dataset may have some inaccuracies and is only current to June 15, 2012. The species identified in this dataset are not inclusive of all aquatic nuisance species, but rather a subset identified to be at risk for transport by recreational activities such as boating and angling. Additionally, the locations where organisims have been identified are also not inclusive and should be treated as a guide. Organisms are limited to the following: American bullfrog, Asian clam, Asian shore crab, Asian tunicate, Australian spotted jellyfish, Chinese mitten crab, New Zealand mudsnail, Colonial sea squirt, Alewife, Bighead carp, Black carp, Flathead catfish, Grass carp, Green crab, Lionfish, Northern snakehead, Quagga mussel, Round Goby, Ruffe, Rusty crayfish, Sea lamprey, Silver carp, Spiny water flea, Veined rapa whelk, Zebra mussel

  2. 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

    identities of 2000 crowns in the images by linking the crowns to stem tags in the field, thus producing a time series of cumulative annual deciduousness for 65 species. Deciduousness showed continuous variation among species rather than distinct phenological categories (ie evergreen and deciduous) that are commonly used in physiological, ecosystem and modeling studies. Some species labelled as evergreen by expert-based classification had annual deciduousness higher than those labelled as deciduous. We found significant, positive relationships between species mean deciduousness and species' leaf phosphorous, photosynthetic capacity and adult relative growth rate, suggesting that higher deciduousness is associated with greater resource acquisition. Comparing May 2015 (during an El Nino drought) and May 2014 (an non El Nino year with normal rainfall), mean deciduousness values for nearly all species was greater in 2015 but with differing levels of intraspecific variation. We discuss how the variation in deciduousness among species, its relationship with plant traits and response to the drought might be incorporated into terrestrial biosphere models of tropical forests to more accurately represent phenology and understand the consequences of community-level variation in phenology for ecosystem processes.

  3. Species of Tursiops

    African Journals Online (AJOL)

    Western lad/“an Dose/7.x Mar. 50/1 Vol. 4, No. 1, pp. ..... collected during the survey. The high percentage of T. aduncns caught in gillnets in the coastal waters indicates that they may be the most abundant inshore dolphin species around Zanzibar. ... This area is relatively shallow (maximum depth. <50m) and may not meet ...

  4. Species Distribution Modelling

    DEFF Research Database (Denmark)

    Gomes, Vitor H. F.; Ijff, Stephanie D.; Raes, Niels

    2018-01-01

    Species distribution models (SDMs) are widely used in ecology and conservation. Presence-only SDMs such as MaxEnt frequently use natural history collections (NHCs) as occurrence data, given their huge numbers and accessibility. NHCs are often spatially biased which may generate inaccuracies in SD...

  5. Species of Tursiops

    African Journals Online (AJOL)

    Abstract—Incidental catches (bycatch) in gillnet fisheries off Zanzibar (Unguja Island), as a source of mortality among several species of dolphins, were reported in a questionnaire survey conducted in 1999. As a follow-up to that survey, from January 2000 to August 2003, we monitored the incidental catches of dolphins ...

  6. Man as a Species.

    Science.gov (United States)

    Solem, Alan; And Others

    Written in 1964, the document represents experimental material of the Anthropology Curriculum Study Project. The objectives of the project were to discuss the evolution of man as distinguished from the evolution of other species and as related to culture, and to emphasize human diversity. Three brief essays are presented. The first, "The…

  7. Endangered Species. Teacher's Guide.

    Science.gov (United States)

    Brown, Mark; And Others

    This unit is intended to examine the causes of the endangerment of Florida's plant and animal species with a detailed look at varied ecological systems. Individual lessons are designed to be used either by individual students progressing at their own rate or by small groups. Units may be modified for use by large groups. (Author/RE)

  8. Translating Dyslexia across Species

    Science.gov (United States)

    Gabel, Lisa A.; Manglani, Monica; Escalona, Nicholas; Cysner, Jessica; Hamilton, Rachel; Pfaffmann, Jeffrey; Johnson, Evelyn

    2016-01-01

    Direct relationships between induced mutation in the "DCDC2" candidate dyslexia susceptibility gene in mice and changes in behavioral measures of visual spatial learning have been reported. We were interested in determining whether performance on a visual-spatial learning and memory task could be translated across species (study 1) and…

  9. Tracking Seed Fates of Tropical Tree Species: Evidence for Seed Caching in a Tropical Forest in North-East India

    Science.gov (United States)

    Sidhu, Swati; Datta, Aparajita

    2015-01-01

    Rodents affect the post-dispersal fate of seeds by acting either as on-site seed predators or as secondary dispersers when they scatter-hoard seeds. The tropical forests of north-east India harbour a high diversity of little-studied terrestrial murid and hystricid rodents. We examined the role played by these rodents in determining the seed fates of tropical evergreen tree species in a forest site in north-east India. We selected ten tree species (3 mammal-dispersed and 7 bird-dispersed) that varied in seed size and followed the fates of 10,777 tagged seeds. We used camera traps to determine the identity of rodent visitors, visitation rates and their seed-handling behavior. Seeds of all tree species were handled by at least one rodent taxon. Overall rates of seed removal (44.5%) were much higher than direct on-site seed predation (9.9%), but seed-handling behavior differed between the terrestrial rodent groups: two species of murid rodents removed and cached seeds, and two species of porcupines were on-site seed predators. In addition, a true cricket, Brachytrupes sp., cached seeds of three species underground. We found 309 caches formed by the rodents and the cricket; most were single-seeded (79%) and seeds were moved up to 19 m. Over 40% of seeds were re-cached from primary cache locations, while about 12% germinated in the primary caches. Seed removal rates varied widely amongst tree species, from 3% in Beilschmiedia assamica to 97% in Actinodaphne obovata. Seed predation was observed in nine species. Chisocheton cumingianus (57%) and Prunus ceylanica (25%) had moderate levels of seed predation while the remaining species had less than 10% seed predation. We hypothesized that seed traits that provide information on resource quantity would influence rodent choice of a seed, while traits that determine resource accessibility would influence whether seeds are removed or eaten. Removal rates significantly decreased (p seed size. Removal rates were significantly

  10. Effects of seed mass on seedling success in Artocarpus heterophyllus L., a tropical tree species of north-east India

    Science.gov (United States)

    Khan, M. L.

    2004-03-01

    I examined the effects of seed mass on performance of seedlings of Artocarpus heterophyllus L. (Moraceae), a large evergreen late successional shade-tolerant tree species in three contrasting light conditions. Seed mass varied many fold from 1.5 to 14 g in A. heterophyllus. Germination and germination time showed a significant correlation with seed mass. Germination differed significantly among three light regimes (50%, 25% and 3%). Seed mass and light level significantly affected seedling survival. The seedlings that emerged from large seeds survived better than those from small seeds under all light regimes. Survival of seedlings was maximum in 25% light regime for all seed mass classes but did not differ significantly from that at 50% light regime. Survival was significantly lower in 3% light as compared to 50% and 25% light regimes. Seedling vigor (expressed in terms of seedling height, leaf area and dry weight) was also significantly affected by seed mass and light regimes. Seedlings that emerged from larger seeds and grew under 50% light regime produced the heaviest seedlings, while those resulting from smaller seeds and grown under 3% light regime produced the lightest seedlings. Resprouting capacity of seedlings after clipping was significantly affected by seed mass and light regime. Seedlings emerging from larger seeds were capable of resprouting several times successively. Resprouting was more pronounced under 50% and 25% light regimes as compared to 3% light. Success of A. heterophyllus regeneration appears to be regulated by an interactive effect of seed mass and light regime.

  11. Hitting an Unintended Target: Phylogeography of Bombus brasiliensis Lepeletier, 1836 and the First New Brazilian Bumblebee Species in a Century (Hymenoptera: Apidae.

    Directory of Open Access Journals (Sweden)

    José Eustáquio Santos Júnior

    Full Text Available This work tested whether or not populations of Bombus brasiliensis isolated on mountain tops of southeastern Brazil belonged to the same species as populations widespread in lowland areas in the Atlantic coast and westward along the Paraná-river valley. Phylogeographic and population genetic analyses showed that those populations were all conspecific. However, they revealed a previously unrecognized, apparently rare, and potentially endangered species in one of the most threatened biodiversity hotspots of the World, the Brazilian Atlantic Forest. This species is described here as Bombus bahiensis sp. n., and included in a revised key for the identification of the bumblebee species known to occur in Brazil. Phylogenetic analyses based on two mtDNA markers suggest this new species to be sister to B. brasiliensis, from which its workers and queens can be easily distinguished by the lack of a yellow hair-band on the first metasomal tergum. The results presented here are consistent with the hypothesis that B. bahiensis sp. n. may have originated from an ancestral population isolated in an evergreen-forest refuge (the so-called Bahia refuge during cold, dry periods of the Pleistocene. This refuge is also known as an important area of endemism for several animal taxa, including other bees. Secondary contact between B. bahiensis and B. brasiliensis may be presently prevented by a strip of semi-deciduous forest in a climate zone characterized by relatively long dry seasons. Considering the relatively limited range of this new species and the current anthropic pressure on its environment, attention should be given to its conservation status.

  12. EFECTO POST-INCENDIO SOBRE EL ECOSISTEMA Araucaria-Nothofagus, PARQUE NACIONAL TOLHUACA.

    OpenAIRE

    PAULINO, LEANDRO

    2006-01-01

    Las comunidades boscosas de Araucaria-M'rhofagus de la Cordillera de Los Andes en Chile y Argentina se han adaptado a los evenlos catastróficos de incendio, los cuales tienen una frecuencia histórica que últimamente se ha incrementado junto a la severidad 186p.

  13. Prices and species diversity

    DEFF Research Database (Denmark)

    Sauer, Johannes

    . Based on a biologically defined species diver-sity index we incorporate biodiversity either as a desirable output or biodiversity loss as a detrimental input. Beside quantitative shadow price measures the main contribu-tion of the work is the evidence that parametric scores of environmental efficiency...... of biodiversity and the appropriate incorporation in stochastic fron-tier models to achieve more realistic measures of production efficiency. We use the empirical example of tobacco production drawing from as well as affecting species diversity in the surrounding forests. We apply a shadow profit distance...... function ap-proach as well as a fixed effects non-radial technique to reveal input specific alloca-tive and output oriented technical efficiency measures as well as measures of envi-ronmental efficiency. We also consider functional consistency by imposing convexity on the translog profit function model...

  14. Biomorphology and rhythm of seasonal development of the relic species Lobelia dortmanna in oligotrophic lakes of Tver region

    Directory of Open Access Journals (Sweden)

    A. G. Lapirov

    2017-07-01

    Full Text Available This article covers the morphology of the vegetative and generative sphere of a rare relic species, Lobelia dortmanna L. (Lobelioideae. This is the first time that using the modular approach a study has analysed the shoot system of this species and described the structures of all three categories: elementary (EM, universal (UM and basic (OM. This paper describes the life form and analyses the rhythm of seasonal development of the species in the lakes of Tver oblast, and provides data on the seed productivity. As a life form, L. dortmanna is a herbaceous polycarpic, un clearly polycentric shallow-rooted plant with a fibrous root system and non-specialized morphological disintegration. The sympodially growing shoot-system of the plant is formed by two types of different-aged anisotropic replacement shoots: dicyclic vegetative-generative semirosette and annual vegetative rosette shoots. The indicator of actual seed productivity equals on average up to 1621 ± 451 seeds per single vegetative-generative shoot. The module structure of L. dortmanna is presented by 10 variants of elementary modules. The main modules are formed on the basis of a monocarpic dicyclic anisotropic monopodial shoot with the following morpho-functional zones distinguished: 1 the lower zone of inhibition; 2 the recovery zone; 3 the upper zone of inhibition 4 the latent generative zone; 5 the main inflorescence. The functional role of the first three morpho-functional zones of a monocarpic shoot is performed by a minimum number of variants of elementary modules. In the rhythm of seasonal development, the authors distinguished 7 consecutive stages: 1 the period of relative rest; 2 vegetative phase; 3 the phase of budding; 4 flowering; 5 frui ting; 6 secondary activities. By the character of rhythm of seasonal development, L. dortmanna belongs to the group of evergreen plants with a long growing season and middle-late summer flowering.

  15. Prior indigenous technological species

    Science.gov (United States)

    Wright, Jason T.

    2018-01-01

    One of the primary open questions of astrobiology is whether there is extant or extinct life elsewhere the solar system. Implicit in much of this work is that we are looking for microbial or, at best, unintelligent life, even though technological artefacts might be much easier to find. Search for Extraterrestrial Intelligence (SETI) work on searches for alien artefacts in the solar system typically presumes that such artefacts would be of extrasolar origin, even though life is known to have existed in the solar system, on Earth, for eons. But if a prior technological, perhaps spacefaring, species ever arose in the solar system, it might have produced artefacts or other technosignatures that have survived to present day, meaning solar system artefact SETI provides a potential path to resolving astrobiology's question. Here, I discuss the origins and possible locations for technosignatures of such a prior indigenous technological species, which might have arisen on ancient Earth or another body, such as a pre-greenhouse Venus or a wet Mars. In the case of Venus, the arrival of its global greenhouse and potential resurfacing might have erased all evidence of its existence on the Venusian surface. In the case of Earth, erosion and, ultimately, plate tectonics may have erased most such evidence if the species lived Gyr ago. Remaining indigenous technosignatures might be expected to be extremely old, limiting the places they might still be found to beneath the surfaces of Mars and the Moon, or in the outer solar system.

  16. The different effects of chilling stress under moderate light intensity on photosystem II compared with photosystem I and subsequent recovery in tropical tree species.

    Science.gov (United States)

    Huang, Wei; Zhang, Shi-Bao; Cao, Kun-Fang

    2010-03-01

    Tropical plants are sensitive to chilling temperatures above zero but it is still unclear whether photosystem I (PSI) or photosystem II (PSII) of tropical plants is mainly affected by chilling temperatures. In this study, the effect of 4 degrees C associated with various light densities on PSII and PSI was studied in the potted seedlings of four tropical evergreen tree species grown in an open field, Khaya ivorensis, Pometia tomentosa, Dalbergia odorifera, and Erythrophleum guineense. After 8 h chilling exposure at the different photosynthetic flux densities of 20, 50, 100, 150 micromol m(-2) s(-1), the maximum quantum yield of PSII (F (v) /F (m)) in all of the four species decreased little, while the quantity of efficient PSI complex (P (m)) remained stable in all species except E. guineense. However, after chilling exposure under 250 micromol m(-2) s(-1) for 24 h, F (v) /F (m) was severely photoinhibited in all species whereas P (m) was relative stable in all plants except E. guineense. At the chilling temperature of 4 degrees C, electron transport from PSII to PSI was blocked because of excessive reduction of primary electron acceptor of PSII. F (v) /F (m) in these species except E. guineense recovered to approximately 90% after 8 h recovery in low light, suggesting the dependence of the recovery of PSII on moderate PSI and/or PSII activity. These results suggest that PSII is more sensitive to chilling temperature under the moderate light than PSI in tropical trees, and the photoinhibition of PSII and closure of PSII reaction centers can serve to protect PSI.

  17. Genomics of Bacillus Species

    Science.gov (United States)

    Økstad, Ole Andreas; Kolstø, Anne-Brit

    Members of the genus Bacillus are rod-shaped spore-forming bacteria belonging to the Firmicutes, the low G+C gram-positive bacteria. The Bacillus genus was first described and classified by Ferdinand Cohn in Cohn (1872), and Bacillus subtilis was defined as the type species (Soule, 1932). Several Bacilli may be linked to opportunistic infections. However, pathogenicity among Bacillus spp. is mainly a feature of bacteria belonging to the Bacillus cereus group, including B. cereus, Bacillus anthracis, and Bacillus thuringiensis. Here we review the genomics of B. cereus group bacteria in relation to their roles as etiological agents of two food poisoning syndromes (emetic and diarrhoeal).

  18. Penicillium species causing onychomycosis.

    Directory of Open Access Journals (Sweden)

    Ramani R

    1994-04-01

    Full Text Available Onychomycosis caused by mould infection is rare. A 40 year old male patient presented with dystrophic finger nails and multiple, erythematous lesions with slightly raised borders and scaling all over the body. The patient was a known diabetic. He did not respond to griseofulvin. Samples from nails and skin scales were cultured. From the nails, Penicillium species and from the skin scales. Trichophyton rubrum were isolated. Ketoconazole therapy (200 mg twice daily x 4 mths led to complete cure with negative cultures and normalization of nails.

  19. Translating dyslexia across species.

    Science.gov (United States)

    Gabel, Lisa A; Manglani, Monica; Escalona, Nicholas; Cysner, Jessica; Hamilton, Rachel; Pfaffmann, Jeffrey; Johnson, Evelyn

    2016-10-01

    Direct relationships between induced mutation in the DCDC2 candidate dyslexia susceptibility gene in mice and changes in behavioral measures of visual spatial learning have been reported. We were interested in determining whether performance on a visual-spatial learning and memory task could be translated across species (study 1) and whether children with reading impairment showed a similar impairment to animal models of the disorder (study 2). Study 1 included 37 participants who completed six trials of four different virtual Hebb-Williams maze configurations. A 2 × 4 × 6 mixed factorial repeated measures ANOVA indicated consistency in performance between humans and mice on these tasks, enabling us to translate across species. Study 2 included a total of 91 participants (age range = 8-13 years). Eighteen participants were identified with reading disorder by performance on the Woodcock-Johnson III Tests of Achievement. Participants completed six trials of five separate virtual Hebb-Williams maze configurations. A 2 × 5 × 6 mixed factorial ANCOVA (gender as covariate) indicated that individuals with reading impairment demonstrated impaired visuo-spatial performance on this task. Overall, results from this study suggest that we are able to translate behavioral deficits observed in genetic animal models of dyslexia to humans with reading impairment. Future studies will utilize the virtual environment to further explore the underlying basis for this impairment.

  20. Save Our Species: Protecting Endangered Species from Pesticides.

    Science.gov (United States)

    Environmental Protection Agency, Washington, DC.

    This full-size poster profiles 11 wildlife species that are endangered. Color illustrations of animals and plants are accompanied by narrative describing their habitats and reasons for endangerment. The reverse side of the poster contains information on the Endangered Species Act, why protecting endangered and threatened species is important, how…

  1. Seasonal patterns of carbon allocation to respiratory pools in 60-yr-old deciduous (Fagus sylvatica) and evergreen (Picea abies) trees assessed via whole-tree stable carbon isotope labeling.

    Science.gov (United States)

    Kuptz, Daniel; Fleischmann, Frank; Matyssek, Rainer; Grams, Thorsten E E

    2011-07-01

    • The CO(2) efflux of adult trees is supplied by recent photosynthates and carbon (C) stores. The extent to which these C pools contribute to growth and maintenance respiration (R(G) and R(M), respectively) remains obscure. • Recent photosynthates of adult beech (Fagus sylvatica) and spruce (Picea abies) trees were labeled by exposing whole-tree canopies to (13) C-depleted CO(2). Label was applied three times during the year (in spring, early summer and late summer) and changes in the stable C isotope composition (δ(13) C) of trunk and coarse-root CO(2) efflux were quantified. • Seasonal patterns in C translocation rate (CTR) and fractional contribution of label to CO(2) efflux (F(Label-Max)) were found. CTR was fastest during early summer. In beech, F(Label-Max) was lowest in spring and peaked in trunks during late summer (0.6 ± 0.1, mean ± SE), whereas no trend was observed in coarse roots. No seasonal dynamics in F(Label-Max) were found in spruce. • During spring, the R(G) of beech trunks was largely supplied by C stores. Recent photosynthates supplied growth in early summer and refilled C stores in late summer. In spruce, CO(2) efflux was constantly supplied by a mixture of stored (c. 75%) and recent (c. 25%) C. The hypothesis that R(G) is exclusively supplied by recent photosynthates was rejected for both species. © 2011 The Authors. New Phytologist © 2011 New Phytologist Trust.

  2. Endangered Species Act Critical Habitat

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Critical habitat (CH) is designated for the survival and recovery of species listed as threatened or endangered under the Endangered Species Act (ESA). Critical...

  3. California Endangered Species Resource Guide.

    Science.gov (United States)

    California State Dept. of Education, Los Angeles.

    This document was developed in response to California Senate Bill No. 885, "The Endangered Species Education Project," that called for a statewide program in which schools adopt a local endangered species, research past and current efforts to preserve the species' habitat, develop and implement an action plan to educate the community…

  4. 76 FR 1405 - Endangered Species

    Science.gov (United States)

    2011-01-10

    ... National Oceanic and Atmospheric Administration RIN 0648-XA128 Endangered Species AGENCY: National Marine... issued under the authority of the Endangered Species Act of 1973, as amended (ESA; 16 U.S.C. 1531 et seq... species (50 CFR parts 222-226). The five-year permit authorizes up to 130 loggerhead, 70 Kemp's ridley, 60...

  5. 76 FR 2348 - Endangered Species

    Science.gov (United States)

    2011-01-13

    ... National Oceanic and Atmospheric Administration RIN 0648-XA140 Endangered Species AGENCY: National Marine... Fort Fisher. The requested permit has been issued under the authority of the Endangered Species Act of... exporting of endangered and threatened species (50 CFR parts 222-226). The North Carolina Aquarium at Fort...

  6. 76 FR 74778 - Endangered Species

    Science.gov (United States)

    2011-12-01

    ... National Oceanic and Atmospheric Administration RIN 0648-XA850 Endangered Species AGENCY: National Marine... has been issued under the authority of the Endangered Species Act of 1973, as amended (ESA; 16 U.S.C... threatened species (50 CFR parts 222-226). The Permit Holder is issued a five-year permit to study shortnose...

  7. 75 FR 78974 - Endangered Species

    Science.gov (United States)

    2010-12-17

    ... National Oceanic and Atmospheric Administration RIN 0648-XA086 Endangered Species AGENCY: National Marine... Comment'' from the Features box on the Applications and Permits for Protected Species (APPS) home page.... 10022-01 is requested under the authority of the Endangered Species Act of 1973, as amended (16 U.S.C...

  8. Ecology of an endemic insular species: Cyclamen balearicum Willk. In the Balearic Islands

    Directory of Open Access Journals (Sweden)

    Grandjanny, Michel

    1997-06-01

    Full Text Available We studied Cyclamen balearicum Willk. in the Balearic Islands with the following two objectives: 1 to describe and discuss its ecology, 2 to discuss the type of rarity it represents. The species grows on Ibiza, Cabrera, Menorca and Mallorca; it is much more frequent on the latter two islands, and is abundant in the moutainous northern part of Mallorca. It is absent from Formentera. The species was found along the entire elevation gradient, thus experiencing a large range of rainfall and temperature conditions. It was encountered not only on limestone but also, occasionally on sandstone and schist in Menorca. Its local habitat is sheltered and shady, with a northern exposure, under a high cover of evergreen woody plants, with a stony soil. Quercus ilex L. and Pinus halepensis Mill, trees and Pistacia lentiscus L. shrubs are the more commonly observed dominant species where C. balearicum occuis. The usual entena applied in defining plant raríty are inadequate in this case, particularly where habitat specificity is concemed.Cyclamen balearicum Willk. ha sido estudiado en las Islas Baleares con dos objetivos principales: 1 describir y discutir su ecología, 2 discutir el tipo de especie rara que representa. La especie se encuentra en Ibiza. Cabrera, Menorca y Mallorca, aunque es mucho más frecuente en las dos últimas islas y abundante en la región montañosa del norte de Mallorca. No se ha encontrado en Formentera. La especie es capaz de crecer bajo una amplia gama de condiciones de precipitación y temperatura, puesto que se encuentra a lo largo de todo el gradiente altitudinal. Crece sobre rocas calcáreas y también, en Menorca, más raramente, sobre areniscas y esquistos. Se desarrolla principalmente en ambientes protegidos y sombreados orientados al norte, bajo la cubierta de árboles perennifohos, sobre suelos pedregosos. Quercus ilex L. y Pinus halepensis Mill, son las especies arbóreas, y Pistacia lentiscus L. la especie arbustiva, que

  9. Insular species swarm goes underground

    DEFF Research Database (Denmark)

    P. S. Reboleira, Ana Sofia; Enghoff, Henrik

    2014-01-01

    -group, an insular species swarm distributed in the archipelagos of Madeira and the Canary Islands. We discuss the differences between the new species and their relatives and present information on the subterranean environment of Madeira. An updated overview of the subterranean biodiversity of millipedes......Two new species of the genus Cylindroiulus Verhoeff, 1894, C. julesvernei and C. oromii, are described from the subterranean ecosystem of Madeira Island, Portugal. Species are illustrated with photographs and diagrammatic drawings. The new species belong to the Cylindroiulus madeirae...

  10. Ring species as demonstrations of the continuum of species formation

    DEFF Research Database (Denmark)

    Pereira, Ricardo José Do Nascimento; Wake, David B.

    2015-01-01

    In the mid-20th century, Ernst Mayr (1942) and Theodosius Dobzhansky (1958) championed the significance of 'circular overlaps' or 'ring species' as the perfect demonstration of the gradual nature of species formation. As an ancestral species expands its range, wrapping around a geographic barrier......, derived taxa within the ring display interactions typical of populations, such as genetic and morphological intergradation, while overlapping taxa at the terminus of the ring behave largely as sympatric, reproductively isolated species. Are ring species extremely rare or are they just difficult to detect......? What conditions favour their formation? Modelling studies have attempted to address these knowledge gaps by estimating the biological parameters that result in stable ring species (Martins et al. 2013), and determining the necessary topographic parameters of the barriers encircled (Monahan et al. 2012...

  11. Native species that can replace exotic species in landscaping

    Directory of Open Access Journals (Sweden)

    Elisabeth Regina Tempel Stumpf

    2015-08-01

    Full Text Available Beyond aesthetics, the contemporary landscaping intends to provide other benefits for humans and environment, especially related to the environmental quality of urban spaces and conservation of the species. A trend in this direction is the reduction in the use of exotic plants in their designs, since, over time, they can become agents of replacement of native flora, as it has occurred in Rio Grande do Sul with many species introduced by settlers. However, the use of exotic species is unjustifiable, because the flora diversity of the Bioma Pampa offers many native species with appropriate features to the ornamental use. The commercial cultivation and the implantation of native species in landscaped areas constitute innovations for plant nurseries and landscapers and can provide a positive reduction in extractivism, contributing to dissemination, exploitation and preservation of native flora, and also decrease the impact of chemical products on environment. So, this work intends to identify native species of Bioma Pampa with features and uses similar to the most used exotic species at Brazilian landscaping. The species were selected from consulting books about native plants of Bioma Pampa and plants used at Brazilian landscaping, considering the similarity on habit and architecture, as well as characteristics of leafs, flowers and/or fruits and environmental conditions of occurrence and cultivation. There were identified 34 native species able to properly replace exotic species commonly used. The results show that many native species of Bioma Pampa have interesting ornamental features to landscape gardening, allowing them to replace exotic species that are traditionally cultivated.

  12. Species of Wadicosa (Araneae, Lycosidae): a new species from Madagascar.

    Science.gov (United States)

    Kronestedt, Torbjörn

    2017-05-10

    Since establishing the wolf spider genus Wadicosa Zyuzin, 1985 (Zyuzin 1985), eleven species have been accepted in it, either by transfer from Lycosa Latreille, 1804 or Pardosa C.L. Koch, 1847 or by original designation (WSC 2017). However, according to Kronestedt (1987), additional species wait to be formally transferred to Wadicosa. The genus is restricted to the Old World, with one species, Wadicosa jocquei Kronestedt, 2015, recently described from Madagascar and surrounding islands.

  13. New mite species associated with certain plant species from Guam

    Directory of Open Access Journals (Sweden)

    Gadi V.P. Reddy

    2011-04-01

    Full Text Available Several new mite species have been reported from certain plants from Guam. Most remarkably, the spider mite, Tetranychus marianae (Prostigmata: Tetranychidae and the predatory mite Phytoseius horridus (Mesostigmata: Phytoseiidae (Solanum melongena have been found on eggplant. The noneconomically important species of Brevipalpus californicus(Banks Prostigmata: Tenuipalpidae,Eupodes sp. (Acarina: Eupodidae and predator Cunaxa sp. (Prostigmata: Cunaxidae have been reported on guava (Psidium guajava L.. Also, the non-economically important species Brevipalpus californicus Prostigmata: Tenuipalpidae, Lepidoglyphus destructor (Astigmata: Glycyphagidae and a predator Amblyseius obtusus, species group Amblyseius near lentiginosus (Mesostigmata: Phytoseiidae, have been recorded on cycad (Cycas micronesica.

  14. Mitigating the Stress of Drought on Soil Respiration by Selective Thinning: Contrasting Effects of Drought on Soil Respiration of Two Oak Species in a Mediterranean Forest

    Directory of Open Access Journals (Sweden)

    Chao-Ting Chang

    2016-11-01

    Full Text Available Drought has been shown to reduce soil respiration (SR in previous studies. Meanwhile, studies of the effect of forest management on SR yielded contrasting results. However, little is known about the combined effect of drought and forest management on SR. To investigate if the drought stress on SR can be mitigated by thinning, we implemented plots of selective thinning and 15% reduced rainfall in a mixed forest consisting of the evergreen Quercus ilex and deciduous Quercus cerrioides; we measured SR seasonally from 2004 to 2007. Our results showed a clear soil moisture threshold of 9%; above this value, SR was strongly dependent on soil temperature, with Q10 of 3.0–3.8. Below this threshold, the relationship between SR and soil temperature weakened. We observed contrasting responses of SR of target oak species to drought and thinning. Reduced rainfall had a strong negative impact on SR of Q. cerrioides, whereas the effect on SR for Q. ilex was marginal or even positive. Meanwhile, selective thinning increased SR of Q. cerrioides, but reduced that of Q. ilex. Overall, our results showed that the negative effect of drought on SR can be offset through selective thinning, but the effect is attenuated with time.

  15. Earthworm species, a searchable database

    Directory of Open Access Journals (Sweden)

    Csuzdi, Cs.

    2012-07-01

    Full Text Available The first earthworm species named was Lumbricus terrestris Linnaeus, 1758. Since then, there were some 6000earthworm (Oligochaeta: Megadrili species names described, from which ca. 3000–3500 are valid. In order to help the orientation in such a huge amount of data a web-based database was created. Each record contains the basic data of the species names described; i.e. family, genus, specific epithet, author, year, reference to the original description and optionally the valid combination of the species name and deposition of type specimens. The database is searchable by every field mentioned and the resulted list can be arranged alphabetically.

  16. Quantifying the invasiveness of species

    Directory of Open Access Journals (Sweden)

    Robert Colautti

    2014-04-01

    Full Text Available The success of invasive species has been explained by two contrasting but non-exclusive views: (i intrinsic factors make some species inherently good invaders; (ii species become invasive as a result of extrinsic ecological and genetic influences such as release from natural enemies, hybridization or other novel ecological and evolutionary interactions. These viewpoints are rarely distinguished but hinge on distinct mechanisms leading to different management scenarios. To improve tests of these hypotheses of invasion success we introduce a simple mathematical framework to quantify the invasiveness of species along two axes: (i interspecific differences in performance among native and introduced species within a region, and (ii intraspecific differences between populations of a species in its native and introduced ranges. Applying these equations to a sample dataset of occurrences of 1,416 plant species across Europe, Argentina, and South Africa, we found that many species are common in their native range but become rare following introduction; only a few introduced species become more common. Biogeographical factors limiting spread (e.g. biotic resistance, time of invasion therefore appear more common than those promoting invasion (e.g. enemy release. Invasiveness, as measured by occurrence data, is better explained by inter-specific variation in invasion potential than biogeographical changes in performance. We discuss how applying these comparisons to more detailed performance data would improve hypothesis testing in invasion biology and potentially lead to more efficient management strategies.

  17. Uncommon Species and Other Features

    Data.gov (United States)

    Vermont Center for Geographic Information — The Vermont Fish and Wildlife Department's Natural Heritage Inventory (NHI) maintains a database of uncommon, rare, threatened and endangered species and natural...

  18. Armillaria species in coniferous stands

    Directory of Open Access Journals (Sweden)

    Anna Żółciak

    2013-12-01

    Full Text Available Identification of the Armillaria species in selected coniferous stands (Scots pine stands, Norway spruce stands and fir stands was the aim of the work carried out on the basis of mating tests and consideration of macroscopic traits of fruit-bodies. One species of Armillaria [A. ostoyae (Romagnesi Herink] was found in Scots pine stands, three species [A. ostoyae, A. cepistipes Velenovský and A. borealis Marxmüller et Korhonen] were found in Norway spruce stands and two species [A. ostoyae and A. cepistipes] were found in fir stands.

  19. Colombian species of Spigelia Colombian species of Spigelia

    Directory of Open Access Journals (Sweden)

    Ewan Joseph

    1947-06-01

    Full Text Available No recent systematic treatment of the Colombian species of Spigelia (Loganiaceae exists. Two species were described in 1818 from New Granada (Colombia by Humboldt, Bonpland and Kunth. The Panamá Canal Zone species have been enumerated by Standley. R. Knuth has listed the Venezuelan species. Spigelia anthelmia L. has been reported from the Dutch west Indian islands of Curacao, Aruba and Bonaire, adjacent to Venezuela, by Boldingh", Spigelia pedunculata R. & S. has been reported from Ecuador by William Jameson.No recent systematic treatment of the Colombian species of Spigelia (Loganiaceae exists. Two species were described in 1818 from New Granada (Colombia by Humboldt, Bonpland and Kunth. The Panamá Canal Zone species have been enumerated by Standley. R. Knuth has listed the Venezuelan species. Spigelia anthelmia L. has been reported from the Dutch west Indian islands of Curacao, Aruba and Bonaire, adjacent to Venezuela, by Boldingh", Spigelia pedunculata R. & S. has been reported from Ecuador by William Jameson.

  20. Multi-species wild herbivore systems vs. domestic single species ...

    African Journals Online (AJOL)

    Multi-species wild herbivore systems vs. domestic single species systems: a comparison of net animal productivity. PS Goodman. Abstract. Reports the results of a study conducted to compare the short and medium term net annual harvested animal production for six areas situated in the semi-arid bushveld of north eastern ...

  1. Removing other Tree Species does not benefit the Timber Species ...

    African Journals Online (AJOL)

    The endemic canopy tree Cephalosphaera usambarensis is a valuable timber species in montane rainforest of Tanzania. Here we evaluate an experiment in which mature trees of species other than C. usambarensis were removed from an area in the East Usambara Mountains. We compared stage/size structure of the ...

  2. Incorporating Context Dependency of Species Interactions in Species Distribution Models.

    Science.gov (United States)

    Lany, Nina K; Zarnetske, Phoebe L; Gouhier, Tarik C; Menge, Bruce A

    2017-07-01

    Species distribution models typically use correlative approaches that characterize the species-environment relationship using occurrence or abundance data for a single species. However, species distributions are determined by both abiotic conditions and biotic interactions with other species in the community. Therefore, climate change is expected to impact species through direct effects on their physiology and indirect effects propagated through their resources, predators, competitors, or mutualists. Furthermore, the sign and strength of species interactions can change according to abiotic conditions, resulting in context-dependent species interactions that may change across space or with climate change. Here, we incorporated the context dependency of species interactions into a dynamic species distribution model. We developed a multi-species model that uses a time-series of observational survey data to evaluate how abiotic conditions and species interactions affect the dynamics of three rocky intertidal species. The model further distinguishes between the direct effects of abiotic conditions on abundance and the indirect effects propagated through interactions with other species. We apply the model to keystone predation by the sea star Pisaster ochraceus on the mussel Mytilus californianus and the barnacle Balanus glandula in the rocky intertidal zone of the Pacific coast, USA. Our method indicated that biotic interactions between P. ochraceus and B. glandula affected B. glandula dynamics across >1000 km of coastline. Consistent with patterns from keystone predation, the growth rate of B. glandula varied according to the abundance of P. ochraceus in the previous year. The data and the model did not indicate that the strength of keystone predation by P. ochraceus varied with a mean annual upwelling index. Balanus glandula cover increased following years with high phytoplankton abundance measured as mean annual chlorophyll-a. M. californianus exhibited the same

  3. Fuzzy species among recombinogenic bacteria

    Directory of Open Access Journals (Sweden)

    Fraser Christophe

    2005-03-01

    Full Text Available Abstract Background It is a matter of ongoing debate whether a universal species concept is possible for bacteria. Indeed, it is not clear whether closely related isolates of bacteria typically form discrete genotypic clusters that can be assigned as species. The most challenging test of whether species can be clearly delineated is provided by analysis of large populations of closely-related, highly recombinogenic, bacteria that colonise the same body site. We have used concatenated sequences of seven house-keeping loci from 770 strains of 11 named Neisseria species, and phylogenetic trees, to investigate whether genotypic clusters can be resolved among these recombinogenic bacteria and, if so, the extent to which they correspond to named species. Results Alleles at individual loci were widely distributed among the named species but this distorting effect of recombination was largely buffered by using concatenated sequences, which resolved clusters corresponding to the three species most numerous in the sample, N. meningitidis, N. lactamica and N. gonorrhoeae. A few isolates arose from the branch that separated N. meningitidis from N. lactamica leading us to describe these species as 'fuzzy'. Conclusion A multilocus approach using large samples of closely related isolates delineates species even in the highly recombinogenic human Neisseria where individual loci are inadequate for the task. This approach should be applied by taxonomists to large samples of other groups of closely-related bacteria, and especially to those where species delineation has historically been difficult, to determine whether genotypic clusters can be delineated, and to guide the definition of species.

  4. Amphibians and reptiles of Guyana, South America: illustrated keys, annotated species accounts, and a biogeographic synopsis

    Science.gov (United States)

    Cole, Charles J.; Townsend, Carol R.; Reynolds, Robert P.; MacCulloch, Ross D.; Lathrop, Amy

    2013-01-01

    at seven lowland sites (in rainforest, savanna, and mixed habitats below 500 m elevation) and three isolated highland sites (in montane forest and evergreen high-tepui forest above 1400 m elevation). Comparisons of these sites are preliminary because sampling of the local faunas remains incomplete. Nevertheless, it is certain that areas of about 2.5 km2 of lowland rainforest can support more than 130 species of amphibians and reptiles (perhaps actually more than 150), while many fewer species (fewer than 30 documented so far) occur in a comparable area of isolated highlands, where low temperatures, frequent cloudiness, and poor soils are relatively unfavorable for amphibians and reptiles. Furthermore, insufficient study has been done in upland sites of intermediate elevations, where lowland and highland faunas overlap significantly, although considerable work is being accomplished in Kaieteur National Park by other investigators. Comparisons of the faunas of the lowland and isolated highland sites showed that very few species occur in common in both the lowlands and isolated highlands; that those few are widespread lowland species that tolerate highland environments; that many endemic species (mostly amphibians) occur in the isolated highlands of the Pakaraima Mountains; and that each of the isolated highlands, lowland savannas, and lowland rainforests at these 10 sites have distinctive faunal elements. No two sites were identical in species composition. Much more work is needed to compare a variety of sites, and especially to incorporate upland sites of intermediate elevations in such comparisons. Five species of sea turtles utilize the limited areas of Atlantic coastal beaches to the northwest of Georgetown. All of these are listed by the International Union for the Conservation of Nature as being of global concern for long-term survival, mostly owing to human predation. The categories of Critically Endangered or Endangered are applied to four of the local sea

  5. Dioecious plants are more precocious than cosexual plants: A comparative study of relative sizes at the onset of sexual reproduction in woody species.

    Science.gov (United States)

    Ohya, Itsuki; Nanami, Satoshi; Itoh, Akira

    2017-08-01

    The reproductive capacities of dioecious plant species may be limited by severe pollen limitation and narrow seed shadows for the two reasons. First, they are unable to self-pollinate, and seed production occurs only with pollinator movement from males to females. Second, only 50% of the individuals in populations contribute to seed production. Despite these handicaps, dioecious plants maintain their populations in plant communities with cooccurring cosexual plants, and no substantial difference in population growth rates has been found between dioecious and cosexual plants. Hence, dioecious plants are thought to mitigate these disadvantages by adopting ecological traits, such as insect pollination, animal-dispersed fleshy fruits, and precocious flowering. We studied the relationship between flowering and plant size in 30 woody species with different sex expressions, leaf habits, fruit types, and maximum plant sizes. The study site was located in an evergreen broad-leaved forest on the island of Honshu, Japan. A phylogenetic linear regression model showed that dioecious species tended to mature at smaller sizes than did cosexual taxa. At the population level, given equal plant densities and reproductive efforts, the precocity of dioecious plants could serve as one of the factors that mitigate the limitations of pollen and seed-shadow handicaps by increasing the density of reproductive individuals in the population. At the individual level, smaller size of onset of flowering may play a role in enhancing reproductive success over a lifetime by increasing reproductive opportunities. We discussed the possible effect of the relationship between precocity and some ecological traits of dioecious plants, such as small flowers pollinated by unspecialized insects, fleshy fruit dispersed by animals, and their preferential occurrence in the tropics and in island habitats. The universality of precocity among dioecious plants should be investigated in diverse plant communities

  6. Protein species as diagnostic markers

    NARCIS (Netherlands)

    Steffen, Pascal; Kwiatkowski, Marcel; Robertson, Wesley D.; Zarrine-Afsar, Mash; Deterra, Diana; Richter, Verena; Schlueter, Hartmut

    2016-01-01

    Many diseases are associated with protein species perturbations. A prominent example of an established diagnostic marker is the glycated protein species of hemoglobin, termed HbA1c. HbA1c concentration is increased in the blood of diabetes mellitus patients due to their poor control of blood glucose

  7. The Colletotrichum gigasporum species complex

    NARCIS (Netherlands)

    Liu, F.; Cai, L.; Crous, P.W.; Damm, U.

    2014-01-01

    In a preliminary analysis, 21 Colletotrichum strains with large conidia preserved in the CBS culture collection clustered with a recently described species, C. gigasporum, forming a clade distinct from other currently known Colletotrichum species complexes. Multi-locus phylogenetic analyses (ITS,

  8. Antifungal compounds from Piper species

    Science.gov (United States)

    Piper is a big genus of the plant family Piperaceae, with more than 700 species widely distributed in the tropical and subtropical regions of the world. Some species are used in folk medicine as analgesics, antiseptics, insecticides, and antimicrobials or for the treatment of toothache, haemorrhoid...

  9. Using ground observations of a digital camera in the VIS-NIR range for quantifying the phenology of Mediterranean woody species

    Science.gov (United States)

    Weil, Gilad; Lensky, Itamar M.; Levin, Noam

    2017-10-01

    The spectral reflectance of most plant species is quite similar, and thus the feasibility of identifying most plant species based on single date multispectral data is very low. Seasonal phenological patterns of plant species may enable to face the challenge of using remote sensing for mapping plant species at the individual level. We used a consumer-grade digital camera with near infra-red capabilities in order to extract and quantify vegetation phenological information in four East Mediterranean sites. After illumination corrections and other noise reduction steps, the phenological patterns of 1839 individuals representing 12 common species were analyzed, including evergreen trees, winter deciduous trees, semi-deciduous summer shrubs and annual herbaceous patches. Five vegetation indices were used to describe the phenology: relative green and red (green/red chromatic coordinate), excess green (ExG), normalized difference vegetation index (NDVI) and green-red vegetation index (GRVI). We found significant differences between the phenology of the various species, and defined the main phenological groups using agglomerative hierarchical clustering. Differences between species and sites regarding the start of season (SOS), maximum of season (MOS) and end of season (EOS) were displayed in detail, using ExG values, as this index was found to have the lowest percentage of outliers. An additional visible band spectral index (relative red) was found as useful for characterizing seasonal phenology, and had the lowest correlation with the other four vegetation indices, which are more sensitive to greenness. We used a linear mixed model in order to evaluate the influences of various factors on the phenology, and found that unlike the significant effect of species and individuals on SOS, MOS and EOS, the sites' location did not have a direct significant effect on the timing of phenological events. In conclusion, the relative advantage of the proposed methodology is the

  10. The C-household of young broad-leaved and conifer tree species exposed to long-term carbon limitation by shading

    Science.gov (United States)

    Weber, Raphael; Hoch, Günter

    2017-04-01

    Non-structural carbohydrates (NSC, i.e. free sugars and starch) are regarded as freely available carbon (C) reserves in plants. They are often quantified to estimate a plant's C-balance, assuming that NSC are controlled by the net-balance between photo-assimilation and C-usage (respiration, growth and other sinks). Within a recent field experiment, we investigated the extent, to which C-reserves (NSC) can be formed in young trees against prevailing C-sink demands (growth) under C-limitation. A total of almost 1000 individuals of two-year-old tree saplings from 6 deciduous, broadleaved species and 4 evergreen conifer species were planted on a field side. Half of the trees per species were treated with long-term C-limitation by exposing them to continuous deep shade conditions (5% of natural PPFD) under a permanent shading tent. C gas-exchange, growth and NSC tissue concentrations were analyzed in shaded and unshaded saplings for two consecutive years. Three months after the beginning of the experiment, leaf photosynthesis acclimatized to the low light conditions, with leaves of shaded trees showing significantly higher SLA and lower light saturation and maximum photosynthesis. During the second season of the experiment, most species exhibited very strong reductions in NSC, but much less pronounced reductions in growth. In contrast, other species, with few exceptions, kept NSC concentrations similar to unshaded controls, while growth virtually stopped under deep shade. In conclusion, we found species-specific strategies in the trees' C-household after two years of C-limitation, that fall into two major carbon allocation strategies: 1) "C-spenders", which deplete C reserves in order to keep up significant growth, and 2) "C-savers", which reduce C sink activities to a minimum in order to store substantial amounts of C reserves. Overall, early-successional species tended to follow the first strategy, while late-successional species tended to save higher C reserve pools

  11. 50 CFR Table 2c to Part 679 - Species Codes: FMP Forage Fish Species (all species of the following families)

    Science.gov (United States)

    2010-10-01

    ... 50 Wildlife and Fisheries 9 2010-10-01 2010-10-01 false Species Codes: FMP Forage Fish Species (all species of the following families) 2c Table 2c to Part 679 Wildlife and Fisheries FISHERY...: FMP Forage Fish Species (all species of the following families) Species Description Code Bristlemouths...

  12. Enolonium Species-Umpoled Enolates

    DEFF Research Database (Denmark)

    Arava, Shlomy; Kumar, Jayprakash N.; Maksymenko, Shimon

    2017-01-01

    Enolonium species/iodo(III) enolates of carbonyl compounds have been suggested to be intermediates in a wide variety of hypervalent iodine induced chemical transformations of ketones, including α-C-O, α-C-N, α-C-C, and alpha-carbon- halide bond formation, but they have never been characterized. We....... Our results open up chemical space for designing a variety of new transformations. We showcase the ability of enolonium species to react with prenyl, crotyl, cinnamyl, and allyl silanes with absolute regioselectivity in up to 92% yield....... report that these elusive umpoled enolates may be made as discrete species that are stable for several minutes at-78 degrees C, and report the first spectroscopic identification of such species. It is shown that enolonium species are direct intermediates in C-O, C-N, C-Cl, and C-C bond forming reactions...

  13. The ethics of species: an introduction

    National Research Council Canada - National Science Library

    Sandler, Ronald L

    2012-01-01

    .... In this book, Ronald L. Sandler examines the value of species and the ethical significance of species boundaries and discusses what these mean for species preservation in the light of global climate change, species...

  14. Annotated bibliography of South African indigenous evergreen forest ecology

    CSIR Research Space (South Africa)

    Geldenhuys, CJ

    1985-01-01

    Full Text Available Annotated references to 519 publications are presented, together with keyword listings and keyword, regional, place name and taxonomic indices. This bibliography forms part of the first phase of the activities of the Forest Biome Task Group....

  15. The rigid pendulum - an antique but evergreen physical model

    Science.gov (United States)

    Butikov, Eugene I.

    1999-11-01

    Various kinds of motion of a rigid pendulum (including swinging with arbitrarily large amplitudes and complete revolutions) are investigated both analytically and with the help of computerized simulations. The simulation experiments reveal many interesting peculiarities of this famous physical model and complement the analytical study of the subject in a manner that is mutually reinforcing.

  16. From green to evergreen: Updating the food revolution | IDRC ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    2011-01-26

    Jan 26, 2011 ... The techniques of biotechnology pioneered by Swaminathan and his colleagues were adopted by other developing countries, and produced the food security that helped set the stage for the rapid ... One is natural resources conservation and enhancement — of soil fertility, water, flora and fauna, and so on.

  17. \\. Santalum album L. (sandalwood) is a small evergreen tree that ...

    Indian Academy of Sciences (India)

    once in late summer and again between October and December, are small and purplish brown. Sandal trees show considerable variation with respect to the shape, size of their leaf and fruit and the extent of heartwood. The heartwood and the essential oil obtained from it are among the oldest known perfumery material and ...

  18. An Evergreen Challenge for Translators – The Translation of Idioms

    Directory of Open Access Journals (Sweden)

    Kovács Gabriella

    2016-12-01

    Full Text Available Translating idioms has always been a challenging decision-making process for translators mainly because not all idioms have direct equivalents in the target language. Translators usually and ideally have a solid knowledge of the target language and its cultural aspects, but even so they cannot match the ability of a native speaker in deciding when – i.e. in what context and text type – an idiom would or would not be appropriate. This study aims to explore the main characteristics of idioms and the difficulties which might occur when translating them. A needs analysis will also be presented, where the various solutions which a group of translator trainees chose while translating certain idioms from the novel “A Game of Thrones” by George R. R. Martin into Hungarian are examined. Their strategies and the appropriateness of their choices are analysed and compared with the options of the experienced literary translator (Tamás Pétersz. We consider this an important endeavour because, based on our experience, we believe that the topic of the translation of idioms should be included into the curriculum and appropriate materials and tasks should be designed to develop the translator trainees’ knowledge and skills in this domain. Therefore, the aim of this analysis is to obtain a clearer view of the difficulties they are dealing with and bear them in mind when designing teaching materials for them.

  19. Schiff Bases: A Short Survey on an Evergreen Chemistry Tool

    Directory of Open Access Journals (Sweden)

    Mauro Panunzio

    2013-10-01

    Full Text Available The review reports a short biography of the Italian naturalized chemist Hugo Schiff and an outline on the synthesis and use of his most popular discovery: the imines, very well known and popular as Schiff Bases. Recent developments on their “metallo-imines” variants have been described. The applications of Schiff bases in organic synthesis as partner in Staudinger and hetero Diels-Alder reactions, as “privileged” ligands in the organometallic complexes and as biological active Schiff intermediates/targets have been reported as well.

  20. Meiofaunal cryptic species challenge species delimitation: the case of the Monocelis lineata (Platyhelminthes: Proseriata) species complex

    NARCIS (Netherlands)

    Scarpa, F.; Cossu, P.; Lai, T.; Sanna, D.; Curini-Galletti, M.; Casu, M.

    2016-01-01

    Given the pending biodiversity crisis, species delimitation is a critically important task in conservation biology, but its efficacy based on single lines of evidence has been questioned as it may not accurately reflect species limits and relationships. Hence, the use of multiple lines of evidence

  1. Molecular Typing of Nocardia Species

    Directory of Open Access Journals (Sweden)

    Seyyed Saeed Eshraghi

    2012-03-01

    Full Text Available Identification of clinically significant Nocardia species is essential for the definitive diagnosis, predict antimicrobial susceptibility, epidemiological purposes, and for an effective treatment. Conventional identification of Nocardia species in routine medical laboratories which is based on phenotypic (cellular morphology, colonial characteristics, biochemical and enzymatic profiles, and chemotaxonomic characteristics is often laborious, and time-consuming. The procedure requires expertise, and newer species can be difficult to differentiate with accuracy from other related species. Alternative methods of identification, such as high performance liquid chromatography (HPLC and molecular biology techniques allow a better characterization of species. The taxonomy of the genus Nocardia has been dramatically been revised during the last decade and more than 30 valid human clinical significance species of Nocardia have been reported. The use of molecular approaches, including 16S rRNA gene sequencing, restriction fragment length polymorphism (RFLP or PCR restriction endonuclease analysis has been the focus of recent investigations to distinguish the isolates of Nocardia from other actinomycetes genera. The methods have revolutionized the characterization of the Nocardiae by providing rapid, sensitive, and accurate identification procedures. The present review describes the currently known medically important pathogenic species of Nocardia.

  2. Revision of the Palearctic Chaetocnema species (Coleoptera: Chrysomelidae: Galerucinae: Alticini)

    Science.gov (United States)

    The Palearctic Chaetocnema species are revised. Seven species are described as new: Chaetocnema belka new species; Chaetocnema bergeali new species; Chaetocnema eastafghanica new species; Chaetocnema franzi new species; Chaetocnema igori new species; Chaetocnema lubischevi new species; Chaetocnema t...

  3. Ninety-eight new species of Trigonopterus weevils from Sundaland and the Lesser Sunda Islands

    Science.gov (United States)

    Riedel, Alexander; Tänzler, Rene; Balke, Michael; Rahmadi, Cahyo; Suhardjono, Yayuk R.

    2014-01-01

    . n., Trigonopterus micans sp. n., Trigonopterus misellus sp. n., Trigonopterus palawanensis sp. n., Trigonopterus pangandaranensis sp. n., Trigonopterus paraflorensis sp. n., Trigonopterus pararugosus sp. n., Trigonopterus parasumbawensis sp. n., Trigonopterus pauxillus sp. n., Trigonopterus payungensis sp. n., Trigonopterus porcatus sp. n., Trigonopterus pseudoflorensis sp. n., Trigonopterus pseudosumbawensis sp. n., Trigonopterus punctatoseriatus sp. n., Trigonopterus ranakensis sp. n., Trigonopterus relictus sp. n., Trigonopterus rinjaniensis sp. n., Trigonopterus roensis sp. n., Trigonopterus rugosostriatus sp. n., Trigonopterus rugosus sp. n., Trigonopterus rutengensis sp. n., Trigonopterus saltator sp. n., Trigonopterus santubongensis sp. n., Trigonopterus sasak sp. n., Trigonopterus satu sp. n., Trigonopterus schulzi sp. n., Trigonopterus sebelas sp. n., Trigonopterus sembilan sp. n., Trigonopterus sepuluh sp. n., Trigonopterus seriatus sp. n., Trigonopterus serratifemur sp. n., Trigonopterus setifer sp. n., Trigonopterus silvestris sp. n., Trigonopterus singkawangensis sp. n., Trigonopterus singularis sp. n., Trigonopterus sinuatus sp. n., Trigonopterus squalidus sp. n., Trigonopterus sumatrensis sp. n., Trigonopterus sumbawensis sp. n., Trigonopterus sundaicus sp. n., Trigonopterus suturalis sp. n., Trigonopterus syarbis sp. n., Trigonopterus telagensis sp. n., Trigonopterus tepalensis sp. n., Trigonopterus tiga sp. n., Trigonopterus trigonopterus sp. n., Trigonopterus tujuh sp. n., Trigonopterus ujungkulonensis sp. n., Trigonopterus variolosus sp. n., Trigonopterus vulcanicus sp. n., Trigonopterus wallacei sp. n.. All new species are authored by the taxonomist-in-charge, Alexander Riedel. Most species belong to the litter fauna of primary wet evergreen forests. This habitat has become highly fragmented in the study area and many of its remnants harbor endemic species. Conservation measures should be intensified, especially in smaller and less famous sites

  4. Species-area relationships are controlled by species traits.

    Science.gov (United States)

    Franzén, Markus; Schweiger, Oliver; Betzholtz, Per-Eric

    2012-01-01

    The species-area relationship (SAR) is one of the most thoroughly investigated empirical relationships in ecology. Two theories have been proposed to explain SARs: classical island biogeography theory and niche theory. Classical island biogeography theory considers the processes of persistence, extinction, and colonization, whereas niche theory focuses on species requirements, such as habitat and resource use. Recent studies have called for the unification of these two theories to better explain the underlying mechanisms that generates SARs. In this context, species traits that can be related to each theory seem promising. Here we analyzed the SARs of butterfly and moth assemblages on islands differing in size and isolation. We tested whether species traits modify the SAR and the response to isolation. In addition to the expected overall effects on the area, traits related to each of the two theories increased the model fit, from 69% up to 90%. Steeper slopes have been shown to have a particularly higher sensitivity to area, which was indicated by species with restricted range (slope = 0.82), narrow dietary niche (slope= 0.59), low abundance (slope= 0.52), and low reproductive potential (slope = 0.51). We concluded that considering species traits by analyzing SARs yields considerable potential for unifying island biogeography theory and niche theory, and that the systematic and predictable effects observed when considering traits can help to guide conservation and management actions.

  5. The functional biogeography of species

    DEFF Research Database (Denmark)

    Carstensen, Daniel W.; Dalsgaard, Bo; Svenning, Jens-Christian

    2013-01-01

    Biogeographical systems can be analyzed as networks of species and geographical units. Within such a biogeographical network, individual species may differ fundamentally in their linkage pattern, and therefore hold different topological roles. To advance our understanding of the relationship...... and a wide altitudinal range-span are related to a wide distribution on many islands and across several biogeographical modules. On the other hand, species restricted to interior forest are mainly characterized as peripherals and, thus, have narrow and localized distributions within biogeographical modules...

  6. Effect of shading and fertilisation on the development of container ...

    African Journals Online (AJOL)

    Effect of shading and fertilisation on the development of container-grown Nothofagus glauca seedlings, a threatened species from central Chile. Rómulo Santelices, Sergio Espinoza, Antonio Cabrera Ariza, Karen Peña-Rojas, Sergio R Donoso ...

  7. Malassezia Species and Pityriasis Versicolor

    National Research Council Canada - National Science Library

    Rodoplu, Gulin

    2016-01-01

    Malassezia species are found in part of the normal human cutaneous commensal flora, however it has been known for many years that the Malassezia yeasts are associated with a number of different human...

  8. Phase One Protected Species Valuation

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Nonmarket valuation research has produced economic value estimates for a variety of threatened, endangered, and rare species around the world. Although over 40 value...

  9. Phase Two Protected Species Valuation

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Nonmarket valuation research has produced economic value estimates for a variety of threatened, endangered, and rare species around the world. Although over 40 value...

  10. Theoretical microbial ecology without species

    Science.gov (United States)

    Tikhonov, Mikhail

    2017-09-01

    Ecosystems are commonly conceptualized as networks of interacting species. However, partitioning natural diversity of organisms into discrete units is notoriously problematic and mounting experimental evidence raises the intriguing question whether this perspective is appropriate for the microbial world. Here an alternative formalism is proposed that does not require postulating the existence of species as fundamental ecological variables and provides a naturally hierarchical description of community dynamics. This formalism allows approaching the species problem from the opposite direction. While the classical models treat a world of imperfectly clustered organism types as a perturbation around well-clustered species, the presented approach allows gradually adding structure to a fully disordered background. The relevance of this theoretical construct for describing highly diverse natural ecosystems is discussed.

  11. The Candida Pathogenic Species Complex

    Science.gov (United States)

    Turner, Siobhán A.; Butler, Geraldine

    2014-01-01

    Candida species are the most common causes of fungal infection. Approximately 90% of infections are caused by five species: Candida albicans, Candida glabrata, Candida tropicalis, Candida parapsilosis, and Candida krusei. Three (C. albicans, C. tropicalis, and C. parapsilosis) belong to the CTG clade, in which the CTG codon is translated as serine and not leucine. C. albicans remains the most commonly isolated but is decreasing relative to the other species. The increasing incidence of C. glabrata is related to its reduced susceptibility to azole drugs. Genome analysis suggests that virulence in the CTG clade is associated with expansion of gene families, particularly of cell wall genes. Similar independent processes took place in the C. glabrata species group. Gene loss and expansion in an ancestor of C. glabrata may have resulted in preadaptations that enabled pathogenicity. PMID:25183855

  12. Infrared spectra of mineral species

    CERN Document Server

    Chukanov, Nikita V

    2014-01-01

    This book details more than 3,000 IR spectra of more than 2,000 mineral species collected during last 30 years. It features full descriptions and analytical data of each sample for which IR spectrum was obtained.

  13. The atlas of endangered species

    National Research Council Canada - National Science Library

    Mackay, R

    2009-01-01

    Vividly illustrated with full-color maps and detailed graphics, The Atlas of Endangered Species catalogs the inhabitants of a wide variety of ecosystems, including forests, mangroves, and coral reefs...

  14. Species doubling and effective Lagrangians

    Energy Technology Data Exchange (ETDEWEB)

    Creutz, M.; Tytgat, M.

    1996-09-01

    Coupling gauge fields to the chiral currents from an effective Lagrangian for pseudoscalar mesons naturally gives rise to a species doubling phenomenon similar to that seen with fermionic fields in lattice gauge theory. 17 refs.

  15. Achromobacter species in cystic fibrosis

    DEFF Research Database (Denmark)

    Hansen, C R; Pressler, T; Ridderberg, W

    2013-01-01

    Achromobacter species leads to chronic infection in an increasing number of CF patients. We report 2 cases of Achromobacter ruhlandii cross-infection between patients after well-described indirect contact....

  16. Evolution of mutualism between species

    Energy Technology Data Exchange (ETDEWEB)

    Post, W.M.; Travis, C.C.; DeAngelis, D.L.

    1980-01-01

    Recent theoretical work on mutualism, the interaction between species populations that is mutually beneficial, is reviewed. Several ecological facts that should be addressed in the construction of dynamic models for mutualism are examined. Basic terminology is clarified. (PSB)

  17. Species Egalitarianism and the Environment

    Directory of Open Access Journals (Sweden)

    Kristin Tiili

    2014-06-01

    Full Text Available A general anthropocentric view of the human species affects the environment and is a major contributing factor in the environmental crisis we are currently facing. A species egalitarian society would have positive effects on the crisis, and particularly in regards to short term goals of decreasing greenhouse gases in the atmosphere. Additionally it would increase the quality of life and alleviate the suffering of countless beings, nonhuman animals and humans alike.

  18. The Origin of Organizational Species

    OpenAIRE

    Ugo Pagano

    1999-01-01

    The paper argues that some of the limitations and problems examined by Darwin and modern biologists in relation to the working of natural selection in the case of speciation may be one aspect of more general rules which have some counterpart in the competitive selection of organisational species in capitalist economic development. In biology the laws of structure and change that characterise the selection among species are very different from those that characterise the selection of the membe...

  19. Chapter 07: Species description pages

    Science.gov (United States)

    Alex C. Wiedenhoeft

    2011-01-01

    These pages are written to be the final step in the identification process; you will be directed to them by the key in Chapter 6. Each species or group of similar species in the same genus has its own set of pages. The information in the first page describes the characteristics of the wood covered in the manual. The page shows images of similar or confusable woods,...

  20. Collective behaviour across animal species.

    Science.gov (United States)

    DeLellis, Pietro; Polverino, Giovanni; Ustuner, Gozde; Abaid, Nicole; Macrì, Simone; Bollt, Erik M; Porfiri, Maurizio

    2014-01-16

    We posit a new geometric perspective to define, detect, and classify inherent patterns of collective behaviour across a variety of animal species. We show that machine learning techniques, and specifically the isometric mapping algorithm, allow the identification and interpretation of different types of collective behaviour in five social animal species. These results offer a first glimpse at the transformative potential of machine learning for ethology, similar to its impact on robotics, where it enabled robots to recognize objects and navigate the environment.

  1. Collective behaviour across animal species

    Science.gov (United States)

    Delellis, Pietro; Polverino, Giovanni; Ustuner, Gozde; Abaid, Nicole; Macrì, Simone; Bollt, Erik M.; Porfiri, Maurizio

    2014-01-01

    We posit a new geometric perspective to define, detect, and classify inherent patterns of collective behaviour across a variety of animal species. We show that machine learning techniques, and specifically the isometric mapping algorithm, allow the identification and interpretation of different types of collective behaviour in five social animal species. These results offer a first glimpse at the transformative potential of machine learning for ethology, similar to its impact on robotics, where it enabled robots to recognize objects and navigate the environment.

  2. Leaf phenology and its associated traits in the wintergreen species Aristotelia chilensis (Mol. Stuntz (Elaeocarpaceae Fenología foliar y sus caracteres asociados en la especie invierno-verde Aristotelia chilensis (Mol. Stuntz (Elaeocarpaceae

    Directory of Open Access Journals (Sweden)

    MARÍA ANGÉLICA DAMASCOS

    2001-12-01

    Full Text Available The post-summer leaf demography of the wintergreen species Aristotelia chilensis growing near San Carlos de Bariloche, Argentina, is described. Its specific leaf mass (SLM, g m-2 is compared to that of the deciduous and evergreen species of the Andean-Patagonian forests and to that of other communities abroad. The pattern of leaf emergence is intermediate, with leaf flush in spring (basal cohort, BC, followed by successive unfolding of the remaining leaves (distal cohort, DC during summer. The senescence of the BC occurs mainly in autumn, with a loss of 11-31 % of its SLM. The DC falls synchronously in mid-spring and the SLM loss in winter is 10-13 %. The SLM of A. chilensis (103.6 ± 6.2 g m-2 is intermediate when compared to the general mean values of deciduous (73.7 ± 15.9 g m-2 and evergreen species (154.8 ± 45.8 g m-2. The SLM of deciduous and evergreen species of three different forests near San Carlos de Bariloche varied significantly at the end of the growing season while that of A. chilensis showed more constant values. The periodicity of leaf production and senescence in A. chilensis allows the maintenance of one leaf cohort throughout the year, covering the carbon demand for flowering and leaf production in spring. This differentiates the deciduous from the wintergreen species, despite their similar mean leaf life span values, while the evergreen species have a longer leaf turnover. Considering the conditions for growth in each studied forest, the leaf life span was not the only factor determining the SLM value. This variable would also depend on multiple stresses that may act during the ontogenesis and evolution of the leaves in each phenological groupSe describe la demografía foliar después del verano de la especie invierno-verde Aristotelia chilensis, creciendo cerca de la ciudad de San Carlos de Bariloche, Argentina. Se compara su peso específico foliar (SLM, g m-2 con los valores de especies deciduas y siempreverdes de los

  3. The Colletotrichum gloeosporioides species complex

    Science.gov (United States)

    Weir, B.S.; Johnston, P.R.; Damm, U.

    2012-01-01

    The limit of the Colletotrichum gloeosporioides species complex is defined genetically, based on a strongly supported clade within the Colletotrichum ITS gene tree. All taxa accepted within this clade are morphologically more or less typical of the broadly defined C. gloeosporioides, as it has been applied in the literature for the past 50 years. We accept 22 species plus one subspecies within the C. gloeosporioides complex. These include C. asianum, C. cordylinicola, C. fructicola, C. gloeosporioides, C. horii, C. kahawae subsp. kahawae, C. musae, C. nupharicola, C. psidii, C. siamense, C. theobromicola, C. tropicale, and C. xanthorrhoeae, along with the taxa described here as new, C. aenigma, C. aeschynomenes, C. alatae, C. alienum, C. aotearoa, C. clidemiae, C. kahawae subsp. ciggaro, C. salsolae, and C. ti, plus the nom. nov. C. queenslandicum (for C. gloeosporioides var. minus). All of the taxa are defined genetically on the basis of multi-gene phylogenies. Brief morphological descriptions are provided for species where no modern description is available. Many of the species are unable to be reliably distinguished using ITS, the official barcoding gene for fungi. Particularly problematic are a set of species genetically close to C. musae and another set of species genetically close to C. kahawae, referred to here as the Musae clade and the Kahawae clade, respectively. Each clade contains several species that are phylogenetically well supported in multi-gene analyses, but within the clades branch lengths are short because of the small number of phylogenetically informative characters, and in a few cases individual gene trees are incongruent. Some single genes or combinations of genes, such as glyceraldehyde-3-phosphate dehydrogenase and glutamine synthetase, can be used to reliably distinguish most taxa and will need to be developed as secondary barcodes for species level identification, which is important because many of these fungi are of biosecurity

  4. Terrestrial animals as invasive species and as species at risk from invasions

    Science.gov (United States)

    Deborah M. Finch; Dean Pearson; Joseph Wunderle; Wayne Arendt

    2010-01-01

    Including terrestrial animal species in the invasive species strategy plan is an important step in invasive species management. Invasions by nonindigenous species threaten nearly 50 percent of imperiled native species in the United States and are the Nation's second leading cause of species endangerment. Invasion and conversion of native habitats by exotic species...

  5. Population structure of a widespread species under balancing selection: the case of Arbutus unedo L.

    Directory of Open Access Journals (Sweden)

    Xabier eSantiso

    2016-01-01

    Full Text Available Arbutus unedo L. is an evergreen shrub with a circum-Mediterranean distribution that also reaches the Eurosiberian region in northern Iberia, Atlantic France, and a disjunct population in southern Ireland. Due to the variety of climatic conditions across its distribution range, the populations of A. unedo were expected to display local adaptation. Conversely, common garden experiments revealed that diverse genotypes from a range of provenances produce similar phenotypes through adaptive plasticity, suggesting the action of stabilizing selection across its climatically heterogeneous range. Nonetheless, since an uniform response might also result from extensive gene flow, we have inferred the population structure of A. unedo and assessed whether its extended and largely one-dimensional range influences gene flow with the help of AFLP genotypes for 491 individuals from 19 populations covering the whole range of the species. As we had anticipated, gene flow is restricted in A. unedo, providing further support to the hypothesis that stabilizing selection is the most likely explanation for the homogeneous phenotypes along the range. The Euro-Siberian populations were not particularly isolated from the Mediterranean. Instead, there was a distinct genetic divide between the populations around the Mediterranean Sea and those sampled along Atlantic coasts from northern Africa up to Ireland. This genetic structure suggests the action of historic rather than biogeographic factors as it seems consistent with a scenario of independent glacial refugia in the Atlantic and Mediterranean portions of the range of A. unedo. Genetic exchange was likewise restricted within each set of populations. Nevertheless, IBD was stronger, and FST increased faster with distance, along the Atlantic, suggesting that gene flow might be larger among Mediterranean populations. Genetic diversity was significantly lower in NW Iberia and Ireland than in other populations whereas

  6. 50 CFR 600.509 - Prohibited species.

    Science.gov (United States)

    2010-10-01

    ... 50 Wildlife and Fisheries 8 2010-10-01 2010-10-01 false Prohibited species. 600.509 Section 600... species. (a) The owner or operator of each FFV must minimize its catch or receipt of prohibited species... its catch of fish received as soon as possible and return all prohibited species and species parts to...

  7. Malassezia Species and Pityriasis Versicolor

    Directory of Open Access Journals (Sweden)

    Gulin Rodoplu

    2016-01-01

    Full Text Available Malassezia species are found in part of the normal human cutaneous commensal flora, however it has been known for many years that the Malassezia yeasts are associated with a number of different human diseases ranging from pityriasis versicolor to seborrhoeic dermatitis. In addition, since the 1980s, they have been reported as causing opportunistic systemic infections. The taxonomy of Malassezia spp. has recently been modified to include 13 obligatorily lipophilic species, plus one non-obligatorily lipophilic species, which only rarely colonizes human hosts and currently the genus consist 14 species as M. furfur, M. pachydermatis, M. sympodialis, M. globosa, M. obtusa, M. slooffiae, M. restricta, M. dermatis, M. japonica, M. nana, M. yamatoensis, M. caprae, M. equina, M. cuniculi. Fastidious growth requirements of Malassezia yeasts defied the initial attempts to culture these organisms and their true identification and the relationship between different species only became apparent with the application of modern molecular techniques. The causative fungus is seen especially in such seborrheic areas as the scalp, face, trunk and upper back. Under the influence of various exogenous or endogenous predisposing factors, these yeasts change from the blastospore form to the mycelial form and become pathogenic. Diagnosis of pityriasis versicolor which is caused by Malassezia species is generally easy and lies on the basis of its clinical appearance and can be confirmed by mycological examination. The diagnosisis is mainly based on direct examination with potassium hydroxide (KOH and demonstration that represents pseudohyphae and blastoconidia as the typical %u201Cspaghetti and meatballs%u201D pattern. Characteristic features of the genus Malassezia include a distinctive morphology and an affinity for lipids in culture. Culture is necessary to recover the infecting strain, especially for epidemiologic purposes and also to test its antifungal susceptibility

  8. Genome Size and Species Diversification.

    Science.gov (United States)

    Kraaijeveld, Ken

    2010-12-01

    Theoretically, there are reasons to believe that large genome size should favour speciation. Several major factors contributing to genome size, such as duplications and transposable element activity have been proposed to facilitate the formation of new species. However, it is also possible that small genome size promotes speciation. For example, selection for genome reduction may be resolved in different ways in incipient species, leading to incompatibilities. Mutations and chromosomal rearrangements may also be more stably inherited in smaller genomes. Here I review the following lines of empirical evidence bearing on this question: (i) Correlations between genome size and species richness of taxa are often negative. (ii) Fossil evidence in lungfish shows that the accumulation of DNA in the genomes of this group coincided with a reduction in species diversity. (iii) Estimates of speciation interval in mammals correlate positively with genome size. (iv) Genome reductions are inferred at the base of particular species radiations and genome expansions at the base of others. (v) Insect clades that have been increasing in diversity up to the present have smaller genomes than clades that have remained stable or have decreased in diversity. The general pattern emerging from these observations is that higher diversification rates are generally found in small-genome taxa. Since diversification rates are the net effect of speciation and extinction, large genomes may thus either constrain speciation rate, increase extinction rate, or both. I argue that some of the cited examples are unlikely to be explained by extinction alone.

  9. Nitrogen supply effects on leaf dynamics and nutritional soil feedbacks of plant species in a sub-arctic tundra ecosystem.

    NARCIS (Netherlands)

    Aerts, R.

    2009-01-01

    Global warming will lead to increased nitrogen supply in tundra ecosystems. How increased N supply affected leaf production, leaf turnover and dead leaf N input into the soil of Empetrum nigrum and Andromeda polifolia (evergreens), Eriophorum vaginatum (graminoid) and Betula nana (deciduous) in a

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

    NARCIS (Netherlands)

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

    2006-01-01

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

  11. Searching for species in haloarchaea.

    Science.gov (United States)

    Papke, R Thane; Zhaxybayeva, Olga; Feil, Edward J; Sommerfeld, Katrin; Muise, Denise; Doolittle, W Ford

    2007-08-28

    Prokaryotic (bacterial and archaeal) species definitions and the biological concepts that underpin them entail clustering (cohesion) among individuals, in terms of genome content and gene sequence similarity. Homologous recombination can maintain gene sequence similarity within, while permitting divergence between, clusters and is thus the basis for recent efforts to apply the Biological Species Concept in prokaryote systematics and ecology. In this study, we examine isolates of the haloarchaeal genus Halorubrum from two adjacent ponds of different salinities at a Spanish saltern and a natural saline lake in Algeria by using multilocus sequence analysis. We show that, although clusters can be defined by concatenation of multiple marker sequences, barriers to exchange between them are leaky. We suggest that no nonarbitrary way to circumscribe "species" is likely to emerge for this group, or by extension, to apply generally across prokaryotes. Arbitrary criteria might have limited practical use, but still must be agreed upon by the community.

  12. Scandinavian Oncophorus (Bryopsida, Oncophoraceae: species, cryptic species, and intraspecific variation

    Directory of Open Access Journals (Sweden)

    Lars Hedenäs

    2017-05-01

    Full Text Available Scandinavian members of the acrocarpous moss genus Oncophorus were revised after field observations had suggested unrecognized diversity. Based on molecular (nuclear: internal transcribed spacers 1 and 2, ITS; plastid: trnGUCC G2 intron, trnG, rps4 gene + trnS-rps4 spacer, rps4 and morphological evidence, four morphologically distinguishable species are recognized, Oncophorus elongatus (I.Hagen Hedenäs, O. integerrimus Hedenäs sp. nov. (syn. O. virens var. elongatus Limpr., O. virens (Hedw. Brid., and O. wahlenbergii Brid. (O. sardous Herzog, syn. nov.. Oncophorus elongatus was earlier recognized, but much of its variation was hidden within O. wahlenbergii. Its circumscription is here expanded to include plants with long leaves having mostly denticulate or sharply denticulate upper margins and with long and narrow marginal cells in the basal portion of the sheathing leaf lamina. The new species O. integerrimus sp. nov. differs from O. virens in having more loosely incurved leaves and entire or almost entire upper leaf margins. Besides these characters, the species in the respective pairs differ in quantitative features of the leaf lamina cells. Several cryptic entities were found, in several cases as molecularly distinct as some of the morphologically recognizable species, and phylogeographic structure is present within O. elongatus and O. virens.

  13. [Reactive nitrogen and oxygen species].

    Science.gov (United States)

    Puzanowska-Tarasiewicz, Helena; Kuźmicka, Ludmiła; Tarasiewicz, Mirosław

    2009-10-01

    Reactive nitrogen species (RNS) and reactive oxygen species (ROS) are mainly free radicals which including non-paired electrons. They are constantly formed as side products of biological reactions. They are also generated directly and indirectly by the cells which were exposed to environmental stress, i.e., UV radiation, ionizing radiation, xenobioticts, light-absorbing compounds, e.g., porphyrines. These factors, which are a source of free radicals, initiate a significant signaling cascade inducing many changes in cells, such as cancerogenic transformation or cell death. Cells protect themselves against oxidative stress by means of antioxidative enzymes and compounds which in their structure have redox sensitive spots.

  14. Estimating species abundance from occurrence

    OpenAIRE

    He, F.; Gaston, K.J.

    2000-01-01

    The number of individuals, or the abundance, of a species\\ud in an area is a fundamental ecological parameter and a\\ud critical consideration when making management and conservation decisions (Andrewartha and Birch 1954; Krebs\\ud 1978; Gaston 1994; Caughley and Gunn 1996). However,\\ud unless the scale is very fine or localized (e.g., in a measurable habitat or a forest stand), abundance is not readily determined. At coarse or regional scales for many species, information on commonness and rar...

  15. The Colletotrichum acutatum species complex

    Science.gov (United States)

    Damm, U.; Cannon, P.F.; Woudenberg, J.H.C.; Crous, P.W.

    2012-01-01

    Colletotrichum acutatum is known as an important anthracnose pathogen of a wide range of host plants worldwide. Numerous studies have reported subgroups within the C. acutatum species complex. Multilocus molecular phylogenetic analysis (ITS, ACT, TUB2, CHS-1, GAPDH, HIS3) of 331 strains previously identified as C. acutatum and other related taxa, including strains from numerous hosts with wide geographic distributions, confirmed the molecular groups previously recognised and identified a series of novel taxa. Thirty-one species are accepted, of which 21 have not previously been recognised. Colletotrichum orchidophilum clusters basal to the C. acutatum species complex. There is a high phenotypic diversity within this complex, and some of the species appear to have preferences to specific hosts or geographical regions. Others appear to be plurivorous and are present in multiple regions. In this study, only C. salicis and C. rhombiforme formed sexual morphs in culture, although sexual morphs have been described from other taxa (especially as laboratory crosses), and there is evidence of hybridisation between different species. One species with similar morphology to C. acutatum but not belonging to this species complex was also described here as new, namely C. pseudoacutatum. Taxonomic novelties: New combinations - Colletotrichum limetticola (R.E. Clausen) Damm, P.F. Cannon & Crous, C. lupini (Bondar) Damm, P.F. Cannon & Crous, C. salicis (Fuckel) Damm, P.F. Cannon & Crous. New species - C. acerbum Damm, P.F. Cannon & Crous, C. australe Damm, P.F. Cannon & Crous, C. brisbanense Damm, P.F. Cannon & Crous, C. cosmi Damm, P.F. Cannon & Crous, C. costaricense Damm, P.F. Cannon & Crous, C. cuscutae Damm, P.F. Cannon & Crous, C. guajavae Damm, P.F. Cannon & Crous, C. indonesiense Damm, P.F. Cannon & Crous, C. johnstonii Damm, P.F. Cannon & Crous, C. kinghornii Damm, P.F. Cannon & Crous, C. laticiphilum Damm, P.F. Cannon & Crous, C. melonis Damm, P.F. Cannon & Crous, C

  16. The Colletotrichum boninense species complex

    Science.gov (United States)

    Damm, U.; Cannon, P.F.; Woudenberg, J.H.C.; Johnston, P.R.; Weir, B.S.; Tan, Y.P.; Shivas, R.G.; Crous, P.W.

    2012-01-01

    Although only recently described, Colletotrichum boninense is well established in literature as an anthracnose pathogen or endophyte of a diverse range of host plants worldwide. It is especially prominent on members of Amaryllidaceae, Orchidaceae, Proteaceae and Solanaceae. Reports from literature and preliminary studies using ITS sequence data indicated that C. boninense represents a species complex. A multilocus molecular phylogenetic analysis (ITS, ACT, TUB2, CHS-1, GAPDH, HIS3, CAL) of 86 strains previously identified as C. boninense and other related strains revealed 18 clades. These clades are recognised here as separate species, including C. boninense s. str., C. hippeastri, C. karstii and 12 previously undescribed species, C. annellatum, C. beeveri, C. brassicicola, C. brasiliense, C. colombiense, C. constrictum, C. cymbidiicola, C. dacrycarpi, C. novae-zelandiae, C. oncidii, C. parsonsiae and C. torulosum. Seven of the new species are only known from New Zealand, perhaps reflecting a sampling bias. The new combination C. phyllanthi was made, and C. dracaenae Petch was epitypified and the name replaced with C. petchii. Typical for species of the C. boninense species complex are the conidiogenous cells with rather prominent periclinal thickening that also sometimes extend to form a new conidiogenous locus or annellations as well as conidia that have a prominent basal scar. Many species in the C. boninense complex form teleomorphs in culture. Taxonomic novelties: New combination - Colletotrichum phyllanthi (H. Surendranath Pai) Damm, P.F. Cannon & Crous. Name replacement - C. petchii Damm, P.F. Cannon & Crous. New species - C. annellatum Damm, P.F. Cannon & Crous, C. beeveri Damm, P.F. Cannon, Crous, P.R. Johnst. & B. Weir, C. brassicicola Damm, P.F. Cannon & Crous, C. brasiliense Damm, P.F. Cannon, Crous & Massola, C. colombiense Damm, P.F. Cannon, Crous, C. constrictum Damm, P.F. Cannon, Crous, P.R. Johnst. & B. Weir, C. cymbidiicola Damm, P.F. Cannon

  17. Vegetation composition and structure influences bird species ...

    African Journals Online (AJOL)

    Vegetation composition and structure influences bird species community assemblages in the highland agricultural landscape of Nyandarua, Kenya. ... Bird species diversity increased with increasing density of woody plant species and vegetation structural heterogeneity. Two gradients of increasing vegetation structural ...

  18. Why so many apparently rare beetles in Chilean temperate rainforests? ¿Por qué hay tantos coleópteros presuntamente raros en los bosques templados de Chile?

    OpenAIRE

    BARRY J RICHARDSON; Arias-Bohart, Elizabeth T.

    2011-01-01

    Species abundance curves were calculated from data sets collected by fogging 52 trees in Nothofagus forest (~46000 specimens) and 24 trees in Araucaria forest (~15000 specimens) in Chile. Neither data set fitted the standard species abundance models. Like similar data sets collected from tropical forests, there were too many species represented by single specimens. The proposal that these were vagrants normally found on other tree species was not supported as, unlike tropical forests, Nothofa...

  19. Description and biological features of a new species of Anagrus Haliday (Hymenoptera, Mymaridae

    Directory of Open Access Journals (Sweden)

    F. Nugnes

    2014-04-01

    Full Text Available Anagrus lindberginae sp. n. (Hymenoptera: Mymaridae, an egg par- asitoid of the leafhopper Lindbergina aurovittata (Homoptera: Cicadellidae, is described from Italy. It is included in the atomus group of Anagrus Haliday and compared with the allied known taxa. The parasitoid’s life cycle is characterized by a long larval diapause from spring to fall, which allows for synchronization with its leafhop- per host; other biological traits of A. lindberginae on the evergreen plant Quercus ilex are discussed.

  20. Species and speciation in the fossil record

    National Research Council Canada - National Science Library

    Allmon, Warren D; Yacobucci, Margaret M

    2016-01-01

    "Although the species is one of the fundamental units of biological classification, there is remarkably little consensus among biologists about what defines a species, even within distinct subdisciplines...

  1. 77 FR 23740 - Invasive Species Advisory Committee

    Science.gov (United States)

    2012-04-20

    ... Advisory Committee (ISAC). Comprised of 30 nonfederal invasive species experts and stakeholders from across... CONTACT: Kelsey Brantley, National Invasive Species Council Program Specialist and ISAC Coordinator, (202...

  2. Community composition and species richness of parasitoids infesting Yponomeuta species in the Netherlands

    NARCIS (Netherlands)

    Cleary, Daniel F.R.

    2004-01-01

    Parasitoid assemblages infesting Yponomeuta species in the Netherlands were investigated. Parasitoid species richness and community composition were related to host species, habitat, temporal and spatial variation. Both community structure and species richness did not differ among habitats. There

  3. Man...An Endangered Species?

    Science.gov (United States)

    Department of the Interior, Washington, DC.

    The general theme of this 1968 yearbook is that man is a threatened species, facing overpopulation and unbridled technology - both self induced. The presentation is broad, relating to many aspects of conservation and natural resources in the United States in a descriptive, non-technical style. The yearbook is divided into major topics: Land…

  4. Georgia Species at Risk Project

    Science.gov (United States)

    2009-06-01

    layers. In addition to Taxodium ascendens, other woody species may include Nyssa biflora, Cephalanthus occidentalis, Liquidambar styraciflua, Clethra...occidentalis, Liquidambar styraciflua, Clethra alnifolia, Lyonia lucida, and Styrax americanus.” This small patch Ecological System covers over 2900 acres...Cephalanthus occidentalis, Liquidambar styraciflua, Clethra alnifolia, Lyonia lucida, and Styrax americanus.” As mapped, this small patch Ecological

  5. Influenza vaccines for avian species

    Science.gov (United States)

    Beginning in Southeast Asia, in 2003, a multi-national epizootic outbreak of H5N1 highly pathogenic avian influenza (HPAI) was identified in commercial poultry and wild bird species. This lineage, originally identified in Southern China in 1996 and then Hong Kong in 1997, caused severe morbidity an...

  6. Thromboelastography in Selected Avian Species

    DEFF Research Database (Denmark)

    Andersen, Sophie Susanna Strindberg; Nielsen, Tenna W; Ribeiro, Ângela M

    2015-01-01

    ) (n = 13), helmeted Guinea fowl ( Numida meleagris ) (n = 12), Amazon parrots (Amazona species) (n = 9), Humboldt penguins ( Spheniscus humboldti ) (n = 6), and domestic chickens (n = 16). Activated partial thromboplastin time, prothrombin time, and fibrinogen were measured as a means of comparison...

  7. storey and canopy tree species

    African Journals Online (AJOL)

    different tree species. The data presented here would therefore help in the planning and management of tropical forest reserves and development of management inteiventions to enhance forest productivity and ecological balance. Materials and methods. Study site. Kalinzu Forest Reserve is a tropical rain forest locate<.! in.

  8. EAMJ Species April 10.indd

    African Journals Online (AJOL)

    2010-04-04

    Apr 4, 2010 ... the market were tested for example voriconazole. This study therefore paves the way for more studies with larger sample sizes, and in different parts of the country in order to understand the local epidemiology of yeast species and to study the local epidemiological susceptibility patterns. These would.

  9. Perpetual flowering in strawberry species

    Science.gov (United States)

    Studies have revealed genetic control of flowering patterns for seasonal flowering (SF) and perpetual flowering (PF) genotypes in the common garden strawberry, with associated links to gene homeologs in diploid alpine strawberry, F. vesca L. Within the genus Fragaria, 22 species and multiple subspec...

  10. and tulbaghia species (wild garlic)

    African Journals Online (AJOL)

    Mgina

    methiin), S-propyl cysteine sulfoxide. (PCSO, propiin), S-allyl-L-cysteine sulfoxide (ACSO, alliin) and S- (trans-1- propenyl)-L-cysteine sulfoxide (PeCSO, isoalliin) in considerable amounts in T. acutiloba. These compounds have been well known to occur in most Allium species. Also, the presence of lectin-like proteins.

  11. Botrytis species on bulb crops

    NARCIS (Netherlands)

    Lorbeer, J.W.; Seyb, A.M.; Boer, de M.; Ende, van den J.E.

    2007-01-01

    Abstract. A number of Botrytis species are pathogens of bulb crops. Botrytis squamosa (teleomorph= Botrytotinia squamosa) causal agent of botrytis leaf blight and B. allii the causal agent of botrytis neck rot are two of the most important fungal diseases of onion. The taxonomics of several of the

  12. Endangered Species: An Educator's Handbook.

    Science.gov (United States)

    Smith, Jean, M., Comp.

    Presented are two articles, an annotated bibliography, and other information useful in teaching about endangered species, especially those found in Florida. The articles provide an ethical rationale, teaching suggestions, and a discussion of the value of wildlife. Descriptions of over 100 pertinent books, periodicals, movies, and filmstrips are in…

  13. SARS – virus jumps species

    Indian Academy of Sciences (India)

    SARS – virus jumps species. Coronavirus reshuffles genes; Rotteir et al, Rotterdam showed the virus to jump from cats to mouse cells after single gene mutation ? Human disease due to virus jumping from wild or domestic animals; Present favourite animal - the cat; - edible or domestic.

  14. Nickel Homeostasis in Helicobacter Species

    NARCIS (Netherlands)

    J. Stoof (Jeroen)

    2011-01-01

    textabstractGastric Helicobacter species are adapted to colonize the acidic environment of the stomach. Colonization with H pylori is life long if untreated, and can lead to gastritis, peptic ulcer disease and eventually to gastric cancer. Although H pylori is sensitive to many antibiotics in vitro,

  15. Comparing perilymph proteomes across species.

    Science.gov (United States)

    Palmer, Jonathan C; Lord, Megan S; Pinyon, Jeremy L; Wise, Andrew K; Lovell, Nigel H; Carter, Paul M; Enke, Ya Lang; Housley, Gary D; Green, Rylie A

    2018-01-01

    Biological components of perilymph affect the electrical performance of cochlear implants. Understanding the perilymph composition of common animal models will improve the understanding of this impact and improve the interpretation of results from animal studies and how it relates to humans. Analysis and comparison of the proteomes of human, guinea pig, and cat perilymph. Multiple perilymph samples from both guinea pigs and cats were analysed via liquid chromatography with tandem mass spectrometry. Proteins were identified using the Mascot database. Human data were obtained from a published dataset. Proteins identified were refined to form a proteome for each species. Over 200 different proteins were found per species. There were 81, 39, and 64 proteins in the final human, guinea pig, and cat proteomes, respectively. Twenty-one proteins were common to all three species. Fifty-two percent of the cat proteome was found in the human proteome, and 31% of the guinea pig was common to human. The cat proteome had similar complexity to the human proteome in three protein classes, whereas the guinea pig had a similar complexity in two. The presence of albumin was significantly higher in human perilymph than in the other two species. Immunoglobulins were more abundant in the human than in the cat proteome. Perilymph proteomes were compared across three species. The degree of crossover of proteins of both guinea pig and cat with human indicate that these animals suitable models for the human cochlea, albeit the cat perilymph is a closer match. NA. Laryngoscope, 128:E47-E52, 2018. © 2017 The American Laryngological, Rhinological and Otological Society, Inc.

  16. Optimal conservation of migratory species.

    Directory of Open Access Journals (Sweden)

    Tara G Martin

    Full Text Available BACKGROUND: Migratory animals comprise a significant portion of biodiversity worldwide with annual investment for their conservation exceeding several billion dollars. Designing effective conservation plans presents enormous challenges. Migratory species are influenced by multiple events across land and sea-regions that are often separated by thousands of kilometres and span international borders. To date, conservation strategies for migratory species fail to take into account how migratory animals are spatially connected between different periods of the annual cycle (i.e. migratory connectivity bringing into question the utility and efficiency of current conservation efforts. METHODOLOGY/PRINCIPAL FINDINGS: Here, we report the first framework for determining an optimal conservation strategy for a migratory species. Employing a decision theoretic approach using dynamic optimization, we address the problem of how to allocate resources for habitat conservation for a Neotropical-Nearctic migratory bird, the American redstart Setophaga ruticilla, whose winter habitat is under threat. Our first conservation strategy used the acquisition of winter habitat based on land cost, relative bird density, and the rate of habitat loss to maximize the abundance of birds on the wintering grounds. Our second strategy maximized bird abundance across the entire range of the species by adding the constraint of maintaining a minimum percentage of birds within each breeding region in North America using information on migratory connectivity as estimated from stable-hydrogen isotopes in feathers. We show that failure to take into account migratory connectivity may doom some regional populations to extinction, whereas including information on migratory connectivity results in the protection of the species across its entire range. CONCLUSIONS/SIGNIFICANCE: We demonstrate that conservation strategies for migratory animals depend critically upon two factors: knowledge of

  17. Species recovery in the United States: Increasing the effectiveness of the Endangered Species Act

    Science.gov (United States)

    Daniel M. Evans; Judy P. Che-Castaldo; Deborah Crouse; Frank W. Davis; Rebecca Epanchin-Niell; Curtis H. Flather; R. Kipp Frohlich; Dale D. Goble; Ya-Wei Li; Timothy D. Male; Lawrence L. Master; Matthew P. Moskwik; Maile C. Neel; Barry R. Noon; Camille Parmesan; Mark W. Schwartz; J. Michael Scott; Byron K. Williams

    2016-01-01

    The Endangered Species Act (ESA) has succeeded in shielding hundreds of species from extinction and improving species recovery over time. However, recovery for most species officially protected by the ESA - i.e., listed species - has been harder to achieve than initially envisioned. Threats to species are persistent and pervasive, funding has been insufficient...

  18. Allelopathy of plant species of pharmaceutical importance to cultivated species

    Directory of Open Access Journals (Sweden)

    Álisson Sobrinho Maranho

    2012-11-01

    Full Text Available This study aimed to identify possible allelopathic effects of leaf aqueous extracts of Baccharis dracunculifolia DC., Pilocarpus pennatifolius Lem., Cyperus rotundus L., Morus rubra L., Casearia sylvestris Sw., and Plectranthus barbatus Andr. on the germination and initial growth of Lactuca sativa L., Brassica oleracea L. cv. capitata, B. oleracea L. cv. italica, B. pekinenses L., B. campestris L., Lycopersicum esculentum Miller, and Eruca sativa L. To obtain the aqueous extracts, leaves previously dried at a 1g.10mL-1 concentration were used, diluted in six solutions (10, 30, 50, 70, 90, and 100% and compared to control, distilled water, with five replications of 10 seeds for all vegetable species. The aqueous extracts of all species showed allelopathic potential for germination of seeds, the germination speed index, and the initial growth of shoots and roots of vegetable crops. The aqueous extracts of C. rotundus and P. barbatus promoted lower and higher allelopathic effects, respectively, and the vegetal structure mostly affected by the extracts was the primary root. The results indicate the existence of allelopathic potential in the species tested, so there’s a need for adopting care procedures when cultivating vegetables with them.

  19. Floral reward in Ranunculaceae species

    Directory of Open Access Journals (Sweden)

    Bożena Denisow

    2016-04-01

    Full Text Available Floral reward is important in ecological and evolutionary perspectives and essential in pollination biology. For example, floral traits, nectar and pollen features are essential for understanding the functional ecology, the dynamics of pollen transport, competition for pollinator services, and patterns of specialization and generalization in plant–pollinator interactions. We believe to present a synthetic description in the field of floral reward in Ranunculaceae family important in pollination biology and indicating connections between ecological and evolutionary approaches. The links between insect visitors’ behaviour and floral reward type and characteristics exist. Ranunculaceae is a family of aboot 1700 species (aboot 60 genera, distributed worldwide, however the most abundant representatives are in temperate and cool regions of the northern and southern hemispheres. The flowers are usually radially symmetric (zygomorphic and bisexual, but in Aconitum, Aquilegia are bilaterally symmetric (zygomorphic. Most Ranunculaceae flowers offer no nectar, only pollen (e.g., Ranunculus, Adonis vernalis, Thalictrum, but numerous species create trophic niches for different wild pollinators (e.g. Osmia, Megachile, Bombus, Andrena (Denisow et al. 2008. Pollen is a source of protein, vitamins, mineral salts, organic acids and hormones, but the nutritional value varies greatly between different plant species. The pollen production can differ significantly between Ranunculacea species. The mass of pollen produced in anthers differ due to variations in the number of developed anthers. For example, interspecies differences are considerable, 49 anthers are noted in Aquilegia vulgaris, 70 anthers in Ranunculus lanuginosus, 120 in Adonis vernalis. A significant intra-species differences’ in the number of anthers are also noted (e.g. 41 to 61 in Aquilegia vulgaris, 23-45 in Ranunculus cassubicus. Pollen production can be up to 62 kg per ha for Ranunculus acer

  20. ICRAF Species Switchboard. Version 1.2

    DEFF Research Database (Denmark)

    Kindt, R.; Ordonez, J.; Smith, E.

    2015-01-01

    The current version of the Agroforestry Species Switchboard documents the presence of a total of 26,135 plant species (33,813 species including synonyms) across 19 web-based databases. When available, hyperlinks to information on the selected species in particular databases are provided. In total...

  1. 50 CFR 91.4 - Eligible species.

    Science.gov (United States)

    2010-10-01

    ... 50 Wildlife and Fisheries 6 2010-10-01 2010-10-01 false Eligible species. 91.4 Section 91.4... species. Five or fewer of the species listed below will be identified as eligible each year; those eligible species will be provided to each contestant with the information provided in § 91.1. (a) Whistling...

  2. Dynamic conservation for migratory species

    Science.gov (United States)

    Reynolds, Mark D.; Sullivan, Brian L.; Hallstein, Eric; Matsumoto, Sandra; Kelling, Steve; Merrifield, Matthew; Fink, Daniel; Johnston, Alison; Hochachka, Wesley M.; Bruns, Nicholas E.; Reiter, Matthew E.; Veloz, Sam; Hickey, Catherine; Elliott, Nathan; Martin, Leslie; Fitzpatrick, John W.; Spraycar, Paul; Golet, Gregory H.; McColl, Christopher; Morrison, Scott A.

    2017-01-01

    In an era of unprecedented and rapid global change, dynamic conservation strategies that tailor the delivery of habitat to when and where it is most needed can be critical for the persistence of species, especially those with diverse and dispersed habitat requirements. We demonstrate the effectiveness of such a strategy for migratory waterbirds. We analyzed citizen science and satellite data to develop predictive models of bird populations and the availability of wetlands, which we used to determine temporal and spatial gaps in habitat during a vital stage of the annual migration. We then filled those gaps using a reverse auction marketplace to incent qualifying landowners to create temporary wetlands on their properties. This approach is a cost-effective way of adaptively meeting habitat needs for migratory species, optimizes conservation outcomes relative to investment, and can be applied broadly to other conservation challenges. PMID:28845449

  3. Ranking species in mutualistic networks.

    Science.gov (United States)

    Domínguez-García, Virginia; Muñoz, Miguel A

    2015-02-02

    Understanding the architectural subtleties of ecological networks, believed to confer them enhanced stability and robustness, is a subject of outmost relevance. Mutualistic interactions have been profusely studied and their corresponding bipartite networks, such as plant-pollinator networks, have been reported to exhibit a characteristic "nested" structure. Assessing the importance of any given species in mutualistic networks is a key task when evaluating extinction risks and possible cascade effects. Inspired in a recently introduced algorithm--similar in spirit to Google's PageRank but with a built-in non-linearity--here we propose a method which--by exploiting their nested architecture--allows us to derive a sound ranking of species importance in mutualistic networks. This method clearly outperforms other existing ranking schemes and can become very useful for ecosystem management and biodiversity preservation, where decisions on what aspects of ecosystems to explicitly protect need to be made.

  4. Charcoal anatomy of forest species

    Directory of Open Access Journals (Sweden)

    Graciela Inés Bolzon de Muñiz1

    2012-09-01

    Full Text Available Vegetal charcoal retains the anatomical structure of the wood and may permit its botanical identification, which depends on species characteristics, the charcoal fragments size and preservation state. Anatomical characterization of ten forest species charcoal was done envisaging the identification and control of illegal charcoal. Differences between gymnosperms and angiosperms are evident in carbonized wood. Vessel diameter was statistically different between wood and charcoal in Vatairea guianensis, Mezilaurus itauba, Calophyllum brasiliense e Qualea cf. acuminata, and vessel frequency in Vatairea guianensis, Manilkara huberi, Qualea cf. acuminata e Simarouba amara. The anatomical structure from wood, in general aspects, is constant during carbonization process using temperature of 450°C, being possible to identify the material by using its cellular components.

  5. Population Genomics of Paramecium Species.

    Science.gov (United States)

    Johri, Parul; Krenek, Sascha; Marinov, Georgi K; Doak, Thomas G; Berendonk, Thomas U; Lynch, Michael

    2017-05-01

    Population-genomic analyses are essential to understanding factors shaping genomic variation and lineage-specific sequence constraints. The dearth of such analyses for unicellular eukaryotes prompted us to assess genomic variation in Paramecium, one of the most well-studied ciliate genera. The Paramecium aurelia complex consists of ∼15 morphologically indistinguishable species that diverged subsequent to two rounds of whole-genome duplications (WGDs, as long as 320 MYA) and possess extremely streamlined genomes. We examine patterns of both nuclear and mitochondrial polymorphism, by sequencing whole genomes of 10-13 worldwide isolates of each of three species belonging to the P. aurelia complex: P. tetraurelia, P. biaurelia, P. sexaurelia, as well as two outgroup species that do not share the WGDs: P. caudatum and P. multimicronucleatum. An apparent absence of global geographic population structure suggests continuous or recent dispersal of Paramecium over long distances. Intergenic regions are highly constrained relative to coding sequences, especially in P. caudatum and P. multimicronucleatum that have shorter intergenic distances. Sequence diversity and divergence are reduced up to ∼100-150 bp both upstream and downstream of genes, suggesting strong constraints imposed by the presence of densely packed regulatory modules. In addition, comparison of sequence variation at non-synonymous and synonymous sites suggests similar recent selective pressures on paralogs within and orthologs across the deeply diverging species. This study presents the first genome-wide population-genomic analysis in ciliates and provides a valuable resource for future studies in evolutionary and functional genetics in Paramecium. © The Author 2017. Published by Oxford University Press on behalf of the Society for Molecular Biology and Evolution. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  6. Endophthalmitis caused by Klebsiella species.

    Science.gov (United States)

    Sridhar, Jayanth; Flynn, Harry W; Kuriyan, Ajay E; Dubovy, Sander; Miller, Darlene

    2014-09-01

    To report the clinical presentation, antibiotic sensitivities, treatment strategies, and visual outcomes associated with endophthalmitis caused by Klebsiella species. A noncomparative consecutive case series. Microbiology database records were retrospectively reviewed for all patients with endophthalmitis caused by Klebsiella species from 1990 to 2012 at a large university referral center. The corresponding clinical records were then reviewed to evaluate the endophthalmitis clinical features and treatment outcomes. Seven patients were identified. Clinical settings included endogenous (n = 3), posttraumatic (n = 2), trabeculectomy bleb-associated (n = 1), and postpenetrating keratoplasty (n = 1). Five patients presented with hypopyon. Presenting visual acuity ranged from 20/60 to light perception in nonendogenous cases and 1/200 to light perception in endogenous cases. Klebsiella was sensitive to aminoglycosides, third-generation cephalosporins, and second- and third-generation fluoroquinolones in all cases. Initial treatment strategies were vitreous tap and injection (n = 4), pars plana vitrectomy with intravitreal antibiotics (n = 2), and anterior chamber tap and injection (n = 1). All three endogenous cases later underwent enucleation or evisceration. In nonendogenous cases, the final visual acuity was 20/70 or better in all 4 patients. Endophthalmitis caused by Klebsiella species is associated with poor visual outcomes. Endogenous cases had high rates of enucleation or evisceration.

  7. An experimental approach to explain the southern Andes elevational treeline.

    Science.gov (United States)

    Fajardo, Alex; Piper, Frida I

    2014-05-01

    • The growth limitation hypothesis (GLH) is the most accepted mechanistic explanation for treeline formation, although it is still uncertain whether it applies across taxa. The successful establishment of Pinus contorta--an exotic conifer species in the southern hemisphere--above the Nothofagus treeline in New Zealand may suggest a different mechanism. We tested the GLH in Nothofagus pumilio and Pinus contorta by comparing seedling performance and carbon (C) balance in response to low temperatures.• At a southern Chilean treeline, we grew seedlings of both species 2 m above ground level, to simulate coupling between temperatures at the meristem and in the air (colder), and at ground level, i.e., decoupling air temperature (relatively milder). We recorded soil and air temperatures as well. After 3 yr, we measured seedling survival and biomass (as a surrogate of growth) and determined nonstructural carbohydrates (NSC).• Nothofagus and Pinus did not differ in survival, which, as a whole, was higher at ground level than at the 2-m height. The root-zone temperature for the growing season was 6.6°C. While biomass and NSC decreased significantly for Nothofagus at the 2-m height compared with ground level (C limitation), these trends were not significant for Pinus• The treeline for Nothofagus pumilio is located at an isotherm that fully matches global patterns; however, its physiological responses to low temperatures differed from those of other treeline species. Support for C limitation in N. pumilio but not in P. contorta indicates that the physiological mechanism explaining their survival and growth at treeline may be taxon-dependent. © 2014 Botanical Society of America, Inc.

  8. Electrophoretic identification of poritid species ( Anthozoa: Scleractinia)

    Science.gov (United States)

    Garthwaite, R. L.; Potts, D. C.; Veron, J. E. N.; Done, T. J.

    1994-01-01

    Electrophoretic surveys of 13 enzyme-coding loci distinguished unambiguously five morphologically defined species of Porites and two species of Goniopora. Each species was identifiable solely by unique, qualitative banding patterns at 1 6 loci. Genetic distances give preliminary estimates that these Porites species diverged from common ancestors 8 22 Ma during the Miocene, and that the two Goniopora species diverged about 3.5 Ma in the Pliocene, assuming Porites evolved from Goniopora 55 million years ago (Ma).

  9. Structural and functional changes in Nothofagus pumilio forests along an altitudinal gradient in Tierra del Fuego, Argentina

    Energy Technology Data Exchange (ETDEWEB)

    Barrera, M.D.; Frangi, J.L.; Perdomo, M.H. [Univ. Nacional de La Plata (Argentina). Facultad de Ciencias Agrarias y Forestales; Richter, L.L.; Pinedo, L.B. [CADIC, Ushuaia (Argentina)

    2000-04-01

    Structural (density, height, basal area, above-ground tree biomass, leaf area index) and functional (leaf phenology, growth rate, fine litter fall, leaf decomposition) traits were quantified in four mature forests of Notofagus pumilio (lenga) along an altitudinal sequence in Tierra del Fuego, Argentina. Three erect forest stands at 220, 440 and 540 m and a krummholz stand at 640 m a.s.l. were selected. Along the altitudinal sequence, stem density increased while DBH, height, biomass, leaf-size and growth period, mean growth rate and decay rate decreased. Dead stems increased and basal area and fine-litter fall decreased with an increase in elevation among erect forests, but these trends inverted at krummholz. We suggest that krummholz is not only a morphological response to the adverse climate but is also a life form with functional advantages.

  10. Alien species in the Finnish weed flora

    Directory of Open Access Journals (Sweden)

    T. HYVÖNEN

    2008-12-01

    Full Text Available The present study aimed at assessing the invasion of alien weed species in Finland based on a review of their occurrence in the Finnish weed flora. The evaluation was conducted for the three phases of the invasion process, i.e. introduction, naturalization and invasion. The literature review revealed that 815 alien weed species occur in Finland of which 314 are regarded as naturalized. Based on their occurrence in different climate zones, the risk of naturalization of new harmful alien weed species was deemed low for those species not currently found in Finland, but higher for species occurring as casual aliens in Finland. In the latter group, 10 species of concern were detected. Exploration of the distribution patterns of naturalized species within Finland revealed species occupancy to be dependent on the residence time of the species. Established neophytes can be expected to extend their ranges and to increase occupation of agricultural habitats in the future.;

  11. Natural Constraints to Species Diversification.

    Directory of Open Access Journals (Sweden)

    Eric Lewitus

    2016-08-01

    Full Text Available Identifying modes of species diversification is fundamental to our understanding of how biodiversity changes over evolutionary time. Diversification modes are captured in species phylogenies, but characterizing the landscape of diversification has been limited by the analytical tools available for directly comparing phylogenetic trees of groups of organisms. Here, we use a novel, non-parametric approach and 214 family-level phylogenies of vertebrates representing over 500 million years of evolution to identify major diversification modes, to characterize phylogenetic space, and to evaluate the bounds and central tendencies of species diversification. We identify five principal patterns of diversification to which all vertebrate families hold. These patterns, mapped onto multidimensional space, constitute a phylogenetic space with distinct properties. Firstly, phylogenetic space occupies only a portion of all possible tree space, showing family-level phylogenies to be constrained to a limited range of diversification patterns. Secondly, the geometry of phylogenetic space is delimited by quantifiable trade-offs in tree size and the heterogeneity and stem-to-tip distribution of branching events. These trade-offs are indicative of the instability of certain diversification patterns and effectively bound speciation rates (for successful clades within upper and lower limits. Finally, both the constrained range and geometry of phylogenetic space are established by the differential effects of macroevolutionary processes on patterns of diversification. Given these properties, we show that the average path through phylogenetic space over evolutionary time traverses several diversification stages, each of which is defined by a different principal pattern of diversification and directed by a different macroevolutionary process. The identification of universal patterns and natural constraints to diversification provides a foundation for understanding the

  12. The Invasive Species Forecasting System

    Science.gov (United States)

    Schnase, John; Most, Neal; Gill, Roger; Ma, Peter

    2011-01-01

    The Invasive Species Forecasting System (ISFS) provides computational support for the generic work processes found in many regional-scale ecosystem modeling applications. Decision support tools built using ISFS allow a user to load point occurrence field sample data for a plant species of interest and quickly generate habitat suitability maps for geographic regions of management concern, such as a national park, monument, forest, or refuge. This type of decision product helps resource managers plan invasive species protection, monitoring, and control strategies for the lands they manage. Until now, scientists and resource managers have lacked the data-assembly and computing capabilities to produce these maps quickly and cost efficiently. ISFS focuses on regional-scale habitat suitability modeling for invasive terrestrial plants. ISFS s component architecture emphasizes simplicity and adaptability. Its core services can be easily adapted to produce model-based decision support tools tailored to particular parks, monuments, forests, refuges, and related management units. ISFS can be used to build standalone run-time tools that require no connection to the Internet, as well as fully Internet-based decision support applications. ISFS provides the core data structures, operating system interfaces, network interfaces, and inter-component constraints comprising the canonical workflow for habitat suitability modeling. The predictors, analysis methods, and geographic extents involved in any particular model run are elements of the user space and arbitrarily configurable by the user. ISFS provides small, lightweight, readily hardened core components of general utility. These components can be adapted to unanticipated uses, are tailorable, and require at most a loosely coupled, nonproprietary connection to the Web. Users can invoke capabilities from a command line; programmers can integrate ISFS's core components into more complex systems and services. Taken together, these

  13. Primate taxonomy: species and conservation.

    Science.gov (United States)

    Rylands, Anthony B; Mittermeier, Russell A

    2014-01-01

    Primatology as a discrete branch of science involving the study of primate behavior and ecology took off in the 1960s after discovery of the importance of primates as models for biomedical research and the realization that primates provide insights into the evolutionary history of humans. Osman Hill's unfortunately incomplete monograph series on the comparative anatomy and taxonomy of the primates(1) and the Napiers' 1967 A Handbook of Living Primates(2) recorded the world's view of primate diversity at this time. This taxonomy remained the baseline for nearly three decades, with the diversity of each genus being represented by some species, but extensively as subspecies. Copyright © 2014 Wiley Periodicals, Inc.

  14. Arsenic Detoxification by Geobacter Species.

    Science.gov (United States)

    Dang, Yan; Walker, David J F; Vautour, Kaitlin E; Dixon, Steven; Holmes, Dawn E

    2017-02-15

    Insight into the mechanisms for arsenic detoxification by Geobacter species is expected to improve the understanding of global cycling of arsenic in iron-rich subsurface sedimentary environments. Analysis of 14 different Geobacter genomes showed that all of these species have genes coding for an arsenic detoxification system (ars operon), and several have genes required for arsenic respiration (arr operon) and methylation (arsM). Genes encoding four arsenic repressor-like proteins were detected in the genome of G. sulfurreducens; however, only one (ArsR1) regulated transcription of the ars operon. Elimination of arsR1 from the G. sulfurreducens chromosome resulted in enhanced transcription of genes coding for the arsenic efflux pump (Acr3) and arsenate reductase (ArsC). When the gene coding for Acr3 was deleted, cells were not able to grow in the presence of either the oxidized or reduced form of arsenic, while arsC deletion mutants could grow in the presence of arsenite but not arsenate. These studies shed light on how Geobacter influences arsenic mobility in anoxic sediments and may help us develop methods to remediate arsenic contamination in the subsurface. This study examines arsenic transformation mechanisms utilized by Geobacter, a genus of iron-reducing bacteria that are predominant in many anoxic iron-rich subsurface environments. Geobacter species play a major role in microbially mediated arsenic release from metal hydroxides in the subsurface. This release raises arsenic concentrations in drinking water to levels that are high enough to cause major health problems. Therefore, information obtained from studies of Geobacter should shed light on arsenic cycling in iron-rich subsurface sedimentary environments, which may help reduce arsenic-associated illnesses. These studies should also help in the development of biosensors that can be used to detect arsenic contaminants in anoxic subsurface environments. We examined 14 different Geobacter genomes and found

  15. VIDAS Listeria species Xpress (LSX).

    Science.gov (United States)

    Johnson, Ronald; Mills, John

    2013-01-01

    The AOAC GovVal study compared the VIDAS Listeria species Xpress (LSX) to the Health Products and Food Branch MFHPB-30 reference method for detection of Listeria on stainless steel. The LSX method utilizes a novel and proprietary enrichment media, Listeria Xpress broth, enabling detection of Listeria species in environmental samples with the automated VIDAS in a minimum of 26 h. The LSX method also includes the use of the chromogenic media, chromID Ottaviani Agosti Agar (OAA) and chromID Lmono for confirmation of LSX presumptive results. In previous AOAC validation studies comparing VIDAS LSX to the U.S. Food and Drug Administration's Bacteriological Analytical Manual (FDA-BAM) and the U.S. Department of Agriculture-Food Safety and Inspection Service (USDA-FSIS) reference methods, the LSX method was approved as AOAC Official Method 2010.02 for the detection of Listeria species in dairy products, vegetables, seafood, raw meats and poultry, and processed meats and poultry, and as AOAC Performance Tested Method 100501 in a variety of foods and on environmental surfaces. The GovVal comparative study included 20 replicate test portions each at two contamination levels for stainless steel where fractionally positive results (5-15 positive results/20 replicate portions tested) were obtained by at least one method at one level. Five uncontaminated controls were included. In the stainless steel artificially contaminated surface study, there were 25 confirmed positives by the VIDAS LSX assay and 22 confirmed positives by the standard culture methods. Chi-square analysis indicated no statistical differences between the VIDAS LSX method and the MFHPB-30 standard methods at the 5% level of significance. Confirmation of presumptive LSX results with the chromogenic OAA and Lmono media was shown to be equivalent to the appropriate reference method agars. The data in this study demonstrate that the VIDAS LSX method is an acceptable alternative method to the MFHPB-30 standard

  16. Placentation in different mammalian species.

    Science.gov (United States)

    Chavatte-Palmer, Pascale; Tarrade, Anne

    2016-06-01

    The placenta is a complex, transient organ associated with viviparity, which is located at the interface of the dam and fetus during pregnancy. It is formed after attachment, or implantation, of the blastocyst on the uterine lining and derives from complex cellular and molecular interactions between uterine and embryonic tissues. In mammals, there are many forms of placentation but this organ has the same function in all species: it is responsible for orchestrating materno-fetal exchanges, together with endocrine and immunological fun