WorldWideScience

Sample records for canopy tree species

  1. NLCD 2001 - Tree Canopy

    Data.gov (United States)

    Minnesota Department of Natural Resources — The National Land Cover Database 2001 tree canopy layer for Minnesota (mapping zones 39-42, 50-51) was produced through a cooperative project conducted by the...

  2. Crown plasticity and competition for canopy space: a new spatially implicit model parameterized for 250 North American tree species.

    Directory of Open Access Journals (Sweden)

    Drew W Purves

    Full Text Available BACKGROUND: Canopy structure, which can be defined as the sum of the sizes, shapes and relative placements of the tree crowns in a forest stand, is central to all aspects of forest ecology. But there is no accepted method for deriving canopy structure from the sizes, species and biomechanical properties of the individual trees in a stand. Any such method must capture the fact that trees are highly plastic in their growth, forming tessellating crown shapes that fill all or most of the canopy space. METHODOLOGY/PRINCIPAL FINDINGS: We introduce a new, simple and rapidly-implemented model--the Ideal Tree Distribution, ITD--with tree form (height allometry and crown shape, growth plasticity, and space-filling, at its core. The ITD predicts the canopy status (in or out of canopy, crown depth, and total and exposed crown area of the trees in a stand, given their species, sizes and potential crown shapes. We use maximum likelihood methods, in conjunction with data from over 100,000 trees taken from forests across the coterminous US, to estimate ITD model parameters for 250 North American tree species. With only two free parameters per species--one aggregate parameter to describe crown shape, and one parameter to set the so-called depth bias--the model captures between-species patterns in average canopy status, crown radius, and crown depth, and within-species means of these metrics vs stem diameter. The model also predicts much of the variation in these metrics for a tree of a given species and size, resulting solely from deterministic responses to variation in stand structure. CONCLUSIONS/SIGNIFICANCE: This new model, with parameters for US tree species, opens up new possibilities for understanding and modeling forest dynamics at local and regional scales, and may provide a new way to interpret remote sensing data of forest canopies, including LIDAR and aerial photography.

  3. Wood density and its radial variation in six canopy tree species differing in shade-tolerance in western Thailand

    OpenAIRE

    Charles A Nock; Geihofer, Daniela; Grabner, Michael; Baker, Patrick J.; BUNYAVEJCHEWIN, SARAYUDH; HIETZ, PETER

    2009-01-01

    Background and Aims Wood density is a key variable for understanding life history strategies in tropical trees. Differences in wood density and its radial variation were related to the shade-tolerance of six canopy tree species in seasonally dry tropical forest in Thailand. In addition, using tree ring measurements, the influence of tree size, age and annual increment on radial density gradients was analysed. Methods Wood density was determined from tree cores using X-ray densitometry. X-ray ...

  4. Effects of canopy tree species on belowground biogeochemistry in a lowland wet tropical forest

    Science.gov (United States)

    Keller, Adrienne B.; Reed, Sasha C.; Townsend, Alan R.; Cleveland, Cory C.

    2013-01-01

    Tropical rain forests are known for their high biological diversity, but the effects of plant diversity on important ecosystem processes in this biome remain unclear. Interspecies differences in both the demand for nutrients and in foliar and litter nutrient concentrations could drive variations in both the pool sizes and fluxes of important belowground resources, yet our understanding of the effects and importance of aboveground heterogeneity on belowground biogeochemistry is poor, especially in the species-rich forests of the wet tropics. To investigate the effects of individual tree species on belowground biogeochemical processes, we used both field and laboratory studies to examine how carbon (C), nitrogen (N), and phosphorus (P) cycles vary under nine different canopy tree species – including three legume and six non-legume species – that vary in foliar nutrient concentrations in a wet tropical forest in southwestern Costa Rica. We found significant differences in belowground C, N and P cycling under different canopy tree species: total C, N and P pools in standing litter varied by species, as did total soil and microbial C and N pools. Rates of soil extracellular acid phosphatase activity also varied significantly among species and functional groups, with higher rates of phosphatase activity under legumes. In addition, across all tree species, phosphatase activity was significantly positively correlated with litter N/P ratios, suggesting a tight coupling between relative N and P inputs and resource allocation to P acquisition. Overall, our results suggest the importance of aboveground plant community composition in promoting belowground biogeochemical heterogeneity at relatively small spatial scales.

  5. Tree Species Establishment in Urban Forest in Relation to Vegetation Composition, Tree Canopy Gap Area and Soil Factors

    Directory of Open Access Journals (Sweden)

    Ilze Jankovska

    2015-12-01

    Full Text Available The study of density and growth of pine, birch and oak seedlings and saplings in canopy gaps in the urban boreal forest in Riga, Latvia, indicates that natural regeneration can increase diversity in small gaps caused by tree mortality, and can ensure conversion from even-aged pine forest. Abundant regeneration in small gaps showed that light (gap area was only one of the factors affecting tree regeneration in the gaps. The depth of the O layer and pH were suggested to be important factors for the establishment and growth of pine and birch. For oak, the main factors for establishment and growth were favorable moisture, higher pH and N concentration. Knowledge of ecological factors affecting the establishment of seedlings and growth of saplings of the most common trees species in the urban boreal forest is needed to predict successional trajectories and to aid management.

  6. Tree Species Establishment in Urban Forest in Relation to Vegetation Composition, Tree Canopy Gap Area and Soil Factors

    OpenAIRE

    Ilze Jankovska; Guntis Brūmelis; Oļģerts Nikodemus; Raimonds Kasparinskis; Vita Amatniece; Gustavs Straupmanis

    2015-01-01

    The study of density and growth of pine, birch and oak seedlings and saplings in canopy gaps in the urban boreal forest in Riga, Latvia, indicates that natural regeneration can increase diversity in small gaps caused by tree mortality, and can ensure conversion from even-aged pine forest. Abundant regeneration in small gaps showed that light (gap area) was only one of the factors affecting tree regeneration in the gaps. The depth of the O layer and pH were suggested to be important factors fo...

  7. Interspecific variation of photosynthesis and leaf characteristics in canopy trees of five species of Dipterocarpaceae in a tropical rain forest.

    Science.gov (United States)

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

    2004-10-01

    Photosynthetic rate, nitrogen concentration and morphological properties of canopy leaves were studied in 18 trees, comprising five dipterocarp species, in a tropical rain forest in Sarawak, Malaysia. Photosynthetic rate at light saturation (Pmax) differed significantly across species, varying from 7 to 18 micro mol m(-2) s(-1). Leaf nitrogen concentration and morphological properties, such as leaf blade and palisade layer thickness, leaf mass per area (LMA) and surface area of mesophyll cells per unit leaf area (Ames/A), also varied significantly across species. Among the relationships with leaf characteristics, Pmax had the strongest correlation with leaf mesophyll parameters, such as palisade cell layer thickness (r2 = 0.76, P palisade layer, with up to five or more layers. We conclude that interspecific variation in photosynthetic capacity in tropical rain forest canopies is influenced more by leaf mesophyll structure than by leaf thickness, LMA or leaf nitrogen concentration.

  8. Distribution of juveniles of tree species along a canopy closure gradient in a tropical cloud forest of the Venezuelan Andes

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    Quevedo-Rojas A

    2016-06-01

    Full Text Available Cloud forests represent a minor portion of the world forests, though outstanding in terms of biodiversity, endemisms, and environmental services provided. Understanding the factors that drive the regeneration and species composition of these forests, and in particular how light availability affects the patterns of juvenile tree distribution in the understory, is critical for conservation and restoration programs. In this study, we determined the range-size and overlap of the abundance distribution of juveniles for 20 tree species in an Andean tropical cloud forest in Venezuela along a gradient of percentage canopy openness (%CO used as a surrogate of light availability. The observed distribution of %CO was then compared with a bounded null model of community structure in order to test light partitioning as a driver of tree species’ coexistence. We measured %CO using hemispherical photography and the abundance and size of juvenile trees in 280 plots of 1-m radius spread over a 32 ha forest area. The distribution of sites was skewed towards the lower end of the %CO gradient (0.5 to 12.8%, while species abundance sharply diminished at both ends of the gradient. Nevertheless, 15 out of 20 species had a non-random distribution in relation to %CO, with many species concentrated near the lower side of the gradient. The observed pattern of species’ overlap was within the 95% confidence limits for the average overlap expected under the bounded null model. These patterns indicate that low canopy openness is the rule in this forest, in spite of the scattered tree-fall gaps, and suggest that light partitioning does not determine the tree community structure at the juvenile stage. High redundancy in light requirements among juveniles of tree species may have a positive effect on species coexistence in cloud forests, thus maintaining a high species diversity. However, other factors such as recruitment limitation and differential growth/carbon-gain among

  9. Assessing the Impact of Central Appalachian Tree Species on Canopy Albedo via Measurement of Leaf Angles from Repeated Ground-based, Drone, and Hemispherical Photography

    Science.gov (United States)

    McNeil, B. E.; Erazo, D.; Heimerl, T.

    2014-12-01

    Satellite measurements of forest albedo are directly used in climate models, and could be used in models of the C and N cycles if we more fully understood the mechanism causing a strong correlation of forest albedo with canopy N and C assimilation. One attractive mechanism posits that tree species have evolved convergent leaf and canopy traits. While the leaf traits of tree species are known to drive variability in canopy N and C assimilation, linking tree species to variability in albedo is challenging because of the difficulty in measuring important canopy traits like leaf angle. To refine techniques for measuring leaf angle, and test the hypothesis that high albedo in the central Appalachians could be linked to the abundance of species with canopy traits of more horizontal leaf angles, we conducted four tests with ground-based, drone, and hemispherical photographs. First, we used a leveled camera on a steep slope to repeatedly, and directly measure the leaf angle of over 400 leaves within the canopies of oak, maple, and beech trees. Across all 21 repetitions (3 times a day on 7 dates between May and July), we observed consistent species differences in mean leaf angle (MLA), with maple always being the most horizontal (MLA = 14-18°) and oak the most vertical (MLA = 19-28°). Second, we again found highly significant species differences in MLA when we used a hexacopter drone with a camera on a self-leveling gimbal to make over 1020 direct measurements of leaf angle from six tree species in three broadleaf deciduous forest plots. Third, to measure MLA of a whole multi-species canopy, we compared a species abundance-weighted plot average of the drone-measured MLA values with an indirect, ground-based hemispherical photograph method. The strong agreement of these direct and indirect plot-level methods finally led us to compare a broader set of 61 plot-level hemispherical photo MLA measurements with canopy albedo measured by AVIRIS in broadleaf deciduous forests. In

  10. The importance of long-distance seed dispersal for the demography and distribution of a canopy tree species.

    Science.gov (United States)

    Caughlin, T Trevor; Ferguson, Jake M; Lichstein, Jeremy W; Bunyavejchewin, Sarayudh; Levey, Douglas J

    2014-04-01

    Long-distance seed dispersal (LDD) is considered a crucial determinant of tree distributions, but its effects depend on demographic processes that enable seeds to establish into adults and that remain poorly understood at large spatial scales. We estimated rates of seed arrival, germination, and survival and growth for a canopy tree species (Miliusa horsfieldii), in a landscape ranging from evergreen forest, where the species' abundance is high, to deciduous forest, where it is extremely low. We then used an individual-based model (IBM) to predict sapling establishment and to compare the relative importance of seed arrival and establishment in explaining the observed distribution of seedlings. Individuals in deciduous forest, far from the source population, experienced multiple benefits (e.g., increased germination rate and seedling survival and growth) from being in a habitat where conspecifics were almost absent. The net effect of these spatial differences in demographic processes was significantly higher estimated sapling establishment probabilities for seeds dispersed long distances into deciduous forest. Despite the high rate of establishment in this habitat, Miliusa is rare in the deciduous forest because the arrival of seeds at long distances from the source population is extremely low. Across the entire landscape, the spatial pattern of seed arrival is much more important than the spatial pattern of establishment for explaining observed seedling distributions. By using dynamic models to link demographic data to spatial patterns, we show that LDD plays a pivotal role in the distribution of this tree in its native habitat.

  11. Tree diversity and canopy cover in cocoa systems in Ghana

    DEFF Research Database (Denmark)

    Asare, Richard; Ræbild, Anders

    2016-01-01

    Cocoa (Theobroma cacao L.) growing systems in Ghana and West Africa consist of diverse tree species and densities.This study was conducted to determine factors that influence tree species configurations and how tree characteristics affect canopy cover in cocoa farms. Eighty-six farmers...

  12. [Characteristics of canopy stomatal conuctance in plantations of three re-vegetation tree species and its sensitivity to environmental factors].

    Science.gov (United States)

    Hu, Yan-ting; Zhao, Ping; Niu, Jun-feng; Sun, Zhen-wei; Zhu, Li-wei

    2015-09-01

    In plantations of three different re-vegetation tree species (Schima superba, Acacia auriculaeformis and Eucalyptus citriodora) in southern China, the stem sap flow of individuals at different DBH classes were monitored using Granier's thermal dissipation probes. With synchronously-measured meteorological data, the canopy stomatal conductance (g(c)) was determined and the responses of g(c) to environmental variables were analyzed. We found that daytime mean g(c) in S. superba forest on average was significantly higher than those of A. auriculaeformis and E. citriodora plantations during a year (except in March). In the three plantations, g(c) was positively logarithmically correlated with photosynthetically active radiation (PAR) (P citriodora forests than in A. auriculaeformis plantation, while the descend degree in S. superba and E. citriodora forests were equal. Overall, our results demonstrated that the native species S. superba is more suitable for re-vegetation in southern China than the exotic species A. auriculaeformis and E. citriodora. PMID:26785542

  13. Photosynthetic characteristics of dominant tree species and canopy in the broadleaved Korean pine forest of Changbai Mountains

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    <正>Based on the light-photosynthesis response measurement at leaf level, combined with over- and under-canopy eddy covariance measurements, research on photosynthetic characteristics of single trees and forest canopy was conducted. The relationship between light intensity and photo-synthetic rates for leaves and canopy can be well fitted by a non-rectangular hyperbola model. Mongolian oak presented a high light compensation point, Lcp (28μmol·m-2·s-1), a light saturation point Lsp (>1800μmol·m-2·s-1), and a maximal net photosynthetic rate Pmax (9.96μmol·m-2·s-1), which suggest that it is a typical heliophilous plant. Mono maple presented the highest apparent quantum efficiencyα(0.066) but the lowest, Lcp (16μmol·m-2·s-1), Lsp (=800μmol·m-2·s-1), and Pmax (4.51μmol·m-2·s-1), which suggest that it is heliophilous plant. Korean pine showed the lowestαvalue but a higher Pmax, which suggest that it is a semi-heliophilous plant. At the canopy level, the values of both or and Pmax approached the upper limit of reported values in temperate forests, while Lcp was within the lower limit. Canopy photosynthetic characteristics were well consistent with those of leaves. Both showed a high ability to photosynthesize. However, environmental stresses, especially high vapor pressure deficits, could significantly reduce the photosynthetic ability of leaves and canopy.

  14. Testing models of tree canopy structure

    Energy Technology Data Exchange (ETDEWEB)

    Martens, S.N. (Los Alamos National Laboratory, NM (United States))

    1994-06-01

    Models of tree canopy structure are difficult to test because of a lack of data which are suitability detailed. Previously, I have made three-dimensional reconstructions of individual trees from measured data. These reconstructions have been used to test assumptions about the dispersion of canopy elements in two- and three-dimensional space. Lacunarity analysis has also been used to describe the texture of the reconstructed canopies. Further tests regarding models of the nature of tree branching structures have been made. Results using probability distribution functions for branching measured from real trees show that branching in Juglans is not Markovian. Specific constraints or rules are necessary to achieve simulations of branching structure which are faithful to the originally measured trees.

  15. Species Turnover across Different Life Stages from Seedlings to Canopy Trees in Swamp Forests of Central Brazil

    Directory of Open Access Journals (Sweden)

    Clarissa G. Fontes

    2015-01-01

    Full Text Available Processes driving the assembly of swamp forest communities have been poorly explored. We analyzed natural regeneration and adult tree communities data of a swamp gallery forest in Central Brazil to discuss the role of ecological filters in shaping plant species turnover in a successional gradient. Species data of 120 plots were used to assess species turnover between natural regeneration and adult tree communities. Our analyses were based on 4995 individuals belonging to 72 species. Community patterns were discerned using ordination analyses. A clear floristic turnover among plant life stages was distinguished. Regeneration community of swamp forests was richer in species composition than the adult community. Tree species commonly found in nonflooded gallery forests were present in the regeneration plots but not in the adult community. Differences in the floristic composition of these two strata suggest that not all species in the seedling stage can stand permanent flooding conditions and only a few tolerant species survive to become adult trees. We propose that natural disturbances play an important role by altering limiting resources, allowing seeds of nonflooded forest species to germinate. This paper elucidates the turnover between plant life stages in swamp forests and suggests mechanisms that may shape these communities.

  16. 100-Meter Resolution Tree Canopy of Alaska - Direct Download

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — This map layer contains tree canopy data for Alaska, in an Albers Equal-Area Conic projection and at a resolution of 100 meters. The tree canopy data were derived...

  17. 100-Meter Resolution Tree Canopy of Hawaii - Direct Download

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — This map layer contains tree canopy data for Hawaii, in an Albers Equal-Area Conic projection and at a resolution of 100 meters. The tree canopy data were derived...

  18. Fat-tailed gene flow in the dioecious canopy tree species Fraxinus mandshurica var. japonica revealed by microsatellites.

    Science.gov (United States)

    Goto, S; Shimatani, K; Yoshimaru, H; Takahashi, Y

    2006-09-01

    Pollen flow, seed dispersal and individual reproductive success can be simultaneously estimated from the genotypes of adults and offspring using stochastic models. Using four polymorphic microsatellite loci, gene flow of the wind-pollinated and wind-seed-dispersed dioecious tree species, Fraxinus mandshurica var. japonica, was quantified in a riparian forest, in northern Japan. In a 10.5-ha plot, 74 female adults, 76 male adults and 292 current-year seedlings were mapped and genotyped, together with 200 seeds. To estimate dispersal kernels of pollen and seeds, we applied normal, exponential power, Weibull, bivariate t-distribution kernels, and two-component models consisting of two normal distribution functions, one with a small and one with a large variance. A two-component pollen flow model with a small contribution (26.1%) from short-distance dispersal (sigma = 7.2 m), and the rest from long-distance flow (sigma = 209.9 m), was chosen for the best-fitting model. The average distance that integrated pollen flows inside and outside the study plot was estimated to be 196.8 m. Tree size and flowering intensity affected reproduction, and there appeared to be critical values that distinguished reproductively successful and unsuccessful adults. In contrast, the gene flow model that estimated both pollen and seed dispersal from established seedlings resulted in extensive seed dispersal, and the expected spatial genetic structures did not satisfactorily fit with the observations, even for the selected model. Our results advanced small-scale individual-based parentage analysis for quantifying fat-tailed gene flow in wind-mediated species, but also clarified its limitations and suggested future possibilities for gene flow studies.

  19. Improving Discrimination of Savanna Tree Species Through a Multiple-Endmember Spectral Angle Mapper Approach: Canopy-Level Analysis

    NARCIS (Netherlands)

    Cho, M.A.; Debba, P.; Mathieu, R.; Naidoo, L.; Aardt, van J.; Asner, G.P.

    2010-01-01

    Differences in within-species phenology and structure are controlled by genetic variation, as well as topography, edaphic properties, and climatic variables across the landscape, and present important challenges to species differentiation with remote sensing. The objectives of this paper are as foll

  20. Tree-mycorrhizal associations detected remotely from canopy spectral properties.

    Science.gov (United States)

    Fisher, Joshua B; Sweeney, Sean; Brzostek, Edward R; Evans, Tom P; Johnson, Daniel J; Myers, Jonathan A; Bourg, Norman A; Wolf, Amy T; Howe, Robert W; Phillips, Richard P

    2016-07-01

    A central challenge in global ecology is the identification of key functional processes in ecosystems that scale, but do not require, data for individual species across landscapes. Given that nearly all tree species form symbiotic relationships with one of two types of mycorrhizal fungi - arbuscular mycorrhizal (AM) and ectomycorrhizal (ECM) fungi - and that AM- and ECM-dominated forests often have distinct nutrient economies, the detection and mapping of mycorrhizae over large areas could provide valuable insights about fundamental ecosystem processes such as nutrient cycling, species interactions, and overall forest productivity. We explored remotely sensed tree canopy spectral properties to detect underlying mycorrhizal association across a gradient of AM- and ECM-dominated forest plots. Statistical mining of reflectance and reflectance derivatives across moderate/high-resolution Landsat data revealed distinctly unique phenological signals that differentiated AM and ECM associations. This approach was trained and validated against measurements of tree species and mycorrhizal association across ~130 000 trees throughout the temperate United States. We were able to predict 77% of the variation in mycorrhizal association distribution within the forest plots (P < 0.001). The implications for this work move us toward mapping mycorrhizal association globally and advancing our understanding of biogeochemical cycling and other ecosystem processes. PMID:27282323

  1. Rank reversals in tree growth along tree size, competition and climatic gradients for four forest canopy dominant species in Central Spain

    NARCIS (Netherlands)

    Sánchez-Gómez, D.; Zavala, M.A.; Schalkwijk, D.B.V.; Urbieta, I.R.; Valladares, F.

    2008-01-01

    Interspecific differences in tree growth patterns with respect to biotic and abiotic factors are key for understanding forest structure and dynamics, and predicting potential changes under climate change. • Repeated observations from the Spanish Forest Inventory (SFI) were used to parameterize maxim

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

    Directory of Open Access Journals (Sweden)

    Cecilia Smith-Ramírez

    2016-05-01

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

  3. Leaf Aging of Amazonian Canopy Trees: Insights to Tropical Ecological Processes and Satellited Detected Canopy Dynamics

    Science.gov (United States)

    Chavana-Bryant, C.; Malhi, Y.; Gerard, F.

    2015-12-01

    Leaf aging is a fundamental driver of changes in leaf traits, thereby, regulating ecosystem processes and remotely-sensed canopy dynamics. Leaf age is particularly important for carbon-rich tropical evergreen forests, as leaf demography (leaf age distribution) has been proposed as a major driver of seasonal productivity in these forests. We explore leaf reflectance as a tool to monitor leaf age and develop a novel spectra-based (PLSR) model to predict age using data from a phenological study of 1,072 leaves from 12 lowland Amazonian canopy tree species in southern Peru. Our results demonstrate monotonic decreases in LWC and Pmass and increase in LMA with age across species; Nmass and Cmassshowed monotonic but species-specific age responses. Spectrally, we observed large age-related variation across species, with the most age-sensitive spectral domains found to be: green peak (550nm), red edge (680-750 nm), NIR (700-850 nm), and around the main water absorption features (~1450 and ~1940 nm). A spectra-based model was more accurate in predicting leaf age (R2= 0.86; %RMSE= 33) compared to trait-based models using single (R2=0.07 to 0.73; %RMSE=7 to 38) and multiple predictors (step-wise analysis; R2=0.76; %RMSE=28). Spectral and trait-based models established a physiochemical basis for the spectral age model. The relative importance of the traits modifying the leaf spectra of aging leaves was: LWC>LMA>Nmass>Pmass,&Cmass. Vegetation indices (VIs), including NDVI, EVI2, NDWI and PRI were all age-dependent. This study highlights the importance of leaf age as a mediator of leaf traits, provides evidence of age-related leaf reflectance changes that have important impacts on VIs used to monitor canopy dynamics and productivity, and proposes a new approach to predicting and monitoring leaf age with important implications for remote sensing.

  4. An estimate of the number of tropical tree species

    NARCIS (Netherlands)

    Slik, J.W.F.; Bongers, F.; Jansen, P.A.; Parren, M.P.E.; Poorter, L.; Tchouto, M.G.P.; Venticinque, E.M.

    2015-01-01

    The high species richness of tropical forests has long been recognized, yet there remains substantial uncertainty regarding the actual number of tropical tree species. Using a pantropical tree inventory database from closed canopy forests, consisting of 657,630 trees belonging to 11,371 species, we

  5. An estimate of the number of tropical tree species

    DEFF Research Database (Denmark)

    Slik, J. W Ferry; Arroyo-Rodríguez, Víctor; Aiba, Shin Ichiro;

    2015-01-01

    The high species richness of tropical forests has long been recognized, yet there remains substantial uncertainty regarding the actual number of tropical tree species. Using a pantropical tree inventory database from closed canopy forests, consisting of 657,630 trees belonging to 11,371 species, ...

  6. Relative abundance estimations of chengal tree in a tropical rainforest by using modified Canopy Fractional Cover (mCFC)

    International Nuclear Information System (INIS)

    Tree species composition estimations are important to sustain forest management. This study challenged estimates of relative abundance of useful timber tree species (chengal) using Hyperion EO-1 satellite data. For the estimation, modified Canopy Fractional Cover (mCFC) was developed using Canopy Fractional Cover (CFC). mCFC was more sensitive to estimate relative abundance of chengal trees rather than Mixture Tuned Matched Filtering (MTMF). Meanwhile, MTMF was more sensitive to estimate the relative abundance of undisturbed forest. Accuracy suggests that the mCFC model is better to explain relative abundance of chengal trees than MTMF. Therefore, it can be concluded that relative abundance of trees species extracted from Hyperion EO-1 satellite data using modified Canopy Fractional Cover is an obtrusive approach used for identifying trees species composition

  7. Relative abundance estimations of Chengal trees in a tropical rainforest by using modified canopy fractional cover (mCFC)

    International Nuclear Information System (INIS)

    Tree species composition estimations are important to sustain forest management. This study estimates relative abundance of useful timber tree species (chengal) using Hyperion EO-1 satellite data. For the estimation, modified Canopy Fractional Cover (mCFC) was developed using Canopy Fractional Cover (CFC). mCFC was more sensitive to estimate relative abundance of chengal trees rather than Mixture Tuned Matched Filtering (MTMF). Meanwhile, MTMF was more sensitive to estimate the relative abundance of undisturbed forest. Accuracy suggests that the mCFC model is better to explain relative abundance of chengal trees than MTMF. Therefore, it can be concluded that relative abundance of tree species extracted from Hyperion EO-1 satellite data using modified Canopy Fractional Cover is an obtrusive approach used for identifying tree species composition

  8. Anatomical basis of the change in leaf mass per area and nitrogen investment with relative irradiance within the canopy of eight temperate tree species

    Science.gov (United States)

    Aranda, I.; Pardo, F.; Gil, L.; Pardos, J. A.

    2004-05-01

    Changes in leaf mass per area (LMA), nitrogen content on a mass-basis (N m) and on an area basis (N a) with relative irradiance were assessed in leaves of eight temperate species harvested at different depths in a canopy. Relative irradiance (GSF) at the points of leaf sampling was estimated by hemispheric photographs. There was a strong species-dependent positive relationship between LMA and GSF for all species. Shade-tolerant species such as Fagus sylvatica showed lower LMA for the same GSF than less tolerant species as Quercus pyrenaica or Quercus petraea. The only evergreen species in the study, Ilex aquifollium, had the highest LMA, independent of light environment, with minimum values much higher than the rest of the broad-leaved species studied. There was no relation between N m and GSF for most species studied and only a very weak relation for the relative shade-intolerant species Q. pyrenaica. Within each species, the pattern of N a investment with regard to GSF was linked mainly to LMA. At the same relative irradiance, differences in N a among species were conditioned both by the LMA-GSF relationship and by the species N m value. The lowest N m value was measured in I. aquifollium (14.3 ± 0.6 mg g -1); intermediate values in Crataegus monogyna (16.9 ± 0.6 mg g -1) and Prunus avium (19.1 ± 0.6 mg g -1) and higher values, all in a narrow range (21.3 ± 0.6 to 23 ± 0.6 mg g -1), were measured for the other five species. Changes in LMA with the relative irradiance were linked both to lamina thickness (LT) and to palisade/spongy parenchyma ratio (PP/SP). In the second case, the LMA changes may be related to an increase in lamina density as palisade parenchyma involves higher cell packing than spongy parenchyma. However, since PP/SP ratio showed a weak species-specific relationship with LMA, the increase in LT should be the main cause of LMA variation.

  9. Water-borne hyphomycetes in tree canopies of Kaiga (Western Ghats, India

    Directory of Open Access Journals (Sweden)

    Naga M. Sudheep

    2013-12-01

    Full Text Available The canopy samples such as trapped leaf litter, trapped sediment (during summer, stemflow and throughfall (during monsoon from five common riparian tree species (Artocarpus heterophyllus, Cassia fistula, Ficus recemosa, Syzygium caryophyllatum and Xylia xylocarpa in Kaiga forest stand of the Western Ghats of southwest India were evaluated for the occurrence of water-borne hyphomycetes. Partially decomposed trapped leaf litter was incubated in bubble chambers followed by filtration to assess conidial output. Sediments accumulated in tree holes or junction of branches were shaken with sterile leaf disks in distilled water followed by incubation of leaf disks in bubble chamber and filtration to find out colonized fungi. Stemflow and throughfall samples were filtered directly to collect free conidia. From five canopy niches, a total of 29 water-borne hyphomycetes were recovered. The species richness was higher in stemflow and throughfall than trapped leaf litter and sediments (14-16 vs. 6-10 species. Although sediments of Syzygium caryophyllatum were acidic (5.1, the conidial output was higher than other tree species. Stemflow and throughfall of Xylea xylocarpa even though alkaline (8.5-8.7 showed higher species richness (6-12 species as well as conidial load than rest of the tree species. Flagellospora curvula and Triscelophorus acuminatus were common in trapped leaf litter and sediments respectively, while conidia of Anguillospora crassa and A. longissima were frequent in stemflow and throughfall. Diversity of water-borne hyphomycetes was highest in throughfall of Xylea xylocarpa followed by throughfall of Ficus recemosa. Our study reconfirms the occurrence and survival of diverse water-borne hyphomycetes in different niches of riparian tree canopies of the Western Ghats during wet and dry regimes and predicts their possible role in canopy as saprophytes, endophytes and alternation of life cycle between canopy and aquatic habitats.

  10. USGS Small-scale Dataset - 100-Meter Resolution Tree Canopy of Hawaii 201301 GeoTIFF

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — This map layer contains tree canopy data for Hawaii, in an Albers Equal-Area Conic projection and at a resolution of 100 meters. The tree canopy data were derived...

  11. Calcium and aluminum cycling in a temperate broadleaved deciduous forest of the eastern USA: relative impacts of tree species, canopy state, and flux type.

    Science.gov (United States)

    Levia, Delphis F; Shiklomanov, Alexey N; Van Stan, John T; Scheick, Carrie E; Inamdar, Shreeram P; Mitchell, Myron J; McHale, Patrick J

    2015-07-01

    Ca/Al molar ratios are commonly used to assess the extent of aluminum stress in forests. This is among the first studies to quantify Ca/Al molar ratios for stemflow. Ca/Al molar ratios in bulk precipitation, throughfall, stemflow, litter leachate, near-trunk soil solution, and soil water were quantified for a deciduous forest in northeastern MD, USA. Data were collected over a 3-year period. The Ca/Al molar ratios in this study were above the threshold for aluminum stress (pH was occasionally an important predictor of calcium and aluminum concentrations, but was not a good predictor of Ca/Al ratio in any of the best-fit models (of >500 examined). This study supplies new data on Ca/Al molar ratios for stemflow from two common deciduous tree species. Future work should examine Ca/Al molar ratios in stemflow of other species and examine both inorganic and organic aluminum species to better gauge the potential for, and understand the dynamics of, aluminum toxicity in the proximal area around tree boles. PMID:26100445

  12. Does canopy nitrogen uptake enhance carbon sequestration by trees?

    Science.gov (United States)

    Nair, Richard K F; Perks, Micheal P; Weatherall, Andrew; Baggs, Elizabeth M; Mencuccini, Maurizio

    2016-02-01

    Temperate forest (15) N isotope trace experiments find nitrogen (N) addition-driven carbon (C) uptake is modest as little additional N is acquired by trees; however, several correlations of ambient N deposition against forest productivity imply a greater effect of atmospheric nitrogen deposition than these studies. We asked whether N deposition experiments adequately represent all processes found in ambient conditions. In particular, experiments typically apply (15) N to directly to forest floors, assuming uptake of nitrogen intercepted by canopies (CNU) is minimal. Additionally, conventional (15) N additions typically trace mineral (15) N additions rather than litter N recycling and may increase total N inputs above ambient levels. To test the importance of CNU and recycled N to tree nutrition, we conducted a mesocosm experiment, applying 54 g N/(15) N ha(-1)  yr(-1) to Sitka spruce saplings. We compared tree and soil (15) N recovery among treatments where enrichment was due to either (1) a (15) N-enriched litter layer, or mineral (15) N additions to (2) the soil or (3) the canopy. We found that 60% of (15) N applied to the canopy was recovered above ground (in needles, stem and branches) while only 21% of (15) N applied to the soil was found in these pools. (15) N recovery from litter was low and highly variable. (15) N partitioning among biomass pools and age classes also differed among treatments, with twice as much (15) N found in woody biomass when deposited on the canopy than soil. Stoichiometrically calculated N effect on C uptake from (15) N applied to the soil, scaled to real-world conditions, was 43 kg C kg N(-1) , similar to manipulation studies. The effect from the canopy treatment was 114 kg C kg N(-1) . Canopy treatments may be critical to accurately represent N deposition in the field and may address the discrepancy between manipulative and correlative studies. PMID:26391113

  13. Realistic Representation of Trees in an Urban Canopy Model

    Science.gov (United States)

    Ryu, Young-Hee; Bou-Zeid, Elie; Wang, Zhi-Hua; Smith, James A.

    2016-05-01

    A single-layer urban canopy model that captures sub-facet heterogeneity and various hydrological processes is further developed to explicitly incorporate trees within the urban canyon. The physical processes associated with trees are shortwave/longwave radiation exchange, including mutual interception and shading by trees and buildings and multiple reflections, sensible heat and latent heat (through transpiration) exchange, and root water uptake. A computationally-efficient geometric approach is applied to the radiation exchanges, requiring a priori knowledge of view factors. These view factors are first obtained from independent Monte Carlo ray-tracing simulations, and subsequently simple relations, which are functions of canyon aspect ratio and tree-crown ratio, are proposed to estimate them. The developed model is evaluated against field observations at two urban sites and one suburban site, showing improved performance for latent heat flux compared to the previous version that only includes ground vegetation. The trees in the urban canopy act to considerably decrease sensible heat flux and increase latent heat flux, and these effects are found to be more significant in the more dense urban site. Sensitivity tests are then performed to examine the effects of tree geometry relative to canyon geometry. The results indicate that the tree-crown size relative to canyon width is the most influential parameter to decrease sensible heat flux and increase latent heat flux, resulting in cooling of the urban area.

  14. Canopy arthropods community within and among oak species in central Mexico

    Institute of Scientific and Technical Information of China (English)

    Efraín TOVAR-SANCHEZ

    2009-01-01

    Quercus rugosa and Q.laurina are species that presents a wide geographical distribution range in temperate forests of Mexico. Oak canopies contain a considerable portion of arthropod diversity and the arthropods fauna fulfill a wide variety of ecological roles. We examined the effect of oak species and seasonal changes on some community structure parameters (diversity, composition, similarity, biomass, rare species, and density of arthropod fauna) of canopy arthropods. In total, 40 oak canopies were fogged during rainy and dry season. A total of 614 identified arthropod morphospecies were recognized belonging to 22 orders associated with tree canopies. A separation of host tree species during both seasons, suggesting a different community structure on host plants species was demonstrated by the principal component analyses (PCA), therefore, differences between oak species results in phenotypes that structure the composition of the arthropod community. Q.laurina registered the highest densities, diversity index and number of rare species in comparison with Q.rugosa. While arthropod biomass showed an inverse pattern. Trees more close to one another (spatial distance) register a more similar canopy arthropod fauna. This study suggests that the trees of Q.laurina could act as a center of biodiversity by the accumulation of arthropod fauna with a considerable number of rare species, which presents wide ecological roles or is involved in critical processes that maintain forest ecosystems[Current Zoology 55(2):132-144,2009].

  15. Ripe Fuji Apple Detection Model Analysis in Natural Tree Canopy

    Directory of Open Access Journals (Sweden)

    Dongjian He

    2012-11-01

    Full Text Available In this work we develop a novel approach for the automatic recognition of red Fuji apples within a tree canopy using three distinguishable color models in order to achieve automated harvesting. How to select the recognition model is important for the certain intelligent harvester employed to perform in real orchards. The L*a*b color model, HSI (Hue, Saturation and Intensity color model and LCD color difference model, which are insensitive to light conditions, are analyzed and applied to detect the fruit under the different lighting conditions because the fruit has the highest red color among the objects in the image. The fuzzy 2-partition entropy, which could discriminate the object and the background in grayscale images and is obtained from the histogram, is applied to the segment the Fuji apples under complex backgrounds. A series of mathematical morphological operations are used to eliminate segmental fragments after segmentation. Finally, the proposed approach is validated on apple images taken in natural tree canopies. A contribution reported in this work, is the voting scheme added to the natural tree canopy which recognizes apples under different light influences.

  16. Leaf function in tropical rain forest canopy trees: the effect of light on leaf morphology and physiology in different-sized trees

    NARCIS (Netherlands)

    Rijkers, T.

    2000-01-01

    In this thesis the effect of constant and fluctuating light availability on several leaf traits was studied for naturally growing trees of different sizes, i.e . from sapling to adult canopy tree, of five species in a tropical rain forest in French Guiana. Leaf acclimation responses were examined th

  17. Taxonomic identity determines N2 fixation by canopy trees across lowland tropical forests.

    Science.gov (United States)

    Wurzburger, Nina; Hedin, Lars O

    2016-01-01

    Legumes capable of fixing atmospheric N2 are abundant and diverse in many tropical forests, but the factors determining ecological patterns in fixation are unresolved. A long-standing idea is that fixation depends on soil nutrients (N, P or Mo), but recent evidence shows that fixation may also differ among N2-fixing species. We sampled canopy-height trees across five species and one species group of N2-fixers along a landscape P gradient, and manipulated P and Mo to seedlings in a shadehouse. Our results identify taxonomy as the major determinant of fixation, with P (and possibly Mo) only influencing fixation following tree-fall disturbances. While 44% of trees did not fix N2, other trees fixed at high rates, with two species functioning as superfixers across the landscape. Our results raise the possibility that fixation is determined by biodiversity, evolutionary history and species-specific traits (tree growth rate, canopy stature and response to disturbance) in the tropical biome.

  18. Weeds under the canopies of tree species submitted to different planting densities and intercropping Plantas daninhas sob copas de espécies arbóreas submetidas a consórcios e densidades de plantio diferentes

    Directory of Open Access Journals (Sweden)

    A.D Souza

    2013-03-01

    Full Text Available Assessing the growth and floristic composition of species that grow under the canopy of trees is important for weed control (WC. The objective of this study was to assess two experiments (E1 and E2, when the trees were two years and one year of age, respectively. In E1, sabiá (S and gliricidia (G were submitted to planting densities from 400 to 1.200 plants ha-1. In E2, growing systems consisting of S, G, and neem (N combinations were compared: SSS, GGG, NNN, GSG, NSN, SGS, NGN, SNS, and GNG (each letter represents a row of plants. A random block design was adopted, with three (E1 and four (E2 replicates. In E1, treatments were arranged as split-plots (species in plots. In E2, the degrees of freedom for treatments (8 were partitioned into growing systems (treatments that involved the same species and between growing system groups (2. Twenty-one weed species were found in E1. Gliricidia attained greater plant height than sabiá, but these species did not differ in canopy diameter, number of weed species per plot, and weed green and dry biomass of the shoot. Higher planting densities resulted in the reduction of all those traits. Twenty-six weed species were found in E2. Growing systems that included gliricidia showed canopies with greater diameters than growing systems that included neem. There were no differences between growing systems for number of weed species per plot and for weed green and dry biomass of the shoot.Avaliações do crescimento e da composição florística de espécies que vegetam sob a copa das árvores são importantes no controle de plantas daninhas (PD. O objetivo deste trabalho foi realizar essas avaliações em dois experimentos (E1 e E2, quando as árvores tinham idades de dois anos e um ano, respectivamente. Em E1, sabiá (S e gliricídia (G foram submetidas a densidades de plantio de 400 a 1.200 plantas ha-1. Em E2, foram comparados sistemas de cultivo de S, G e nim (N: SSS, GGG, NNN, GSG, NSN, SGS, NGN, SNS e GNG

  19. Phenology, seed dispersal and difficulties in natural recruitment of the canopy tree Pachira quinata (Malvaceae).

    Science.gov (United States)

    Castellanos, Maria Clara; Stevenson, Pablo R

    2011-06-01

    Life history and recruitment information of tropical trees in natural populations is scarce even for important commercial species. This study focused on a widely exploited Neotropical canopy species, Pachira quinata (Malvaceae), at the southernmost, wettest limit of its natural distribution, in the Colombian Amazonia. We studied phenological patterns, seed production and natural densities; assessed the importance of seed dispersal and density-dependent effects on recruitment, using field experiments. At this seasonal forest P. quinata was overrepresented by large adult trees and had very low recruitment caused by the combination of low fruit production, high seed predation and very high seedling mortality under continuous canopies mostly due to damping off pathogens. There was no evidence of negative distance or density effects on recruitment, but a clear requirement of canopy gaps for seedling survival and growth, where pathogen incidence was drastically reduced. In spite of the strong dependence on light for survival of seedlings, seeds germinated readily in the dark. At the study site, the population of P. quinata appeared to be declining, likely because recruitment depended on the rare combination of large gap formation with the presence of reproductive trees nearby. The recruitment biology of this species makes it very vulnerable to any type of logging in natural populations. PMID:21717860

  20. Correlations between canopy gaps and species diversity in broad-leaved and Korean pine mixed forests

    Institute of Scientific and Technical Information of China (English)

    ZHAO Xiuhai; ZHANG Chunyu; ZHENG Jingming

    2006-01-01

    Regeneration of tree species associated with canopy gaps in broad-leaved Korean pine forests was investigated.Species diversity in gaps and under closed canopy was compared,the relationship between biodiversity and gap structure was analyzed.Results indicate that there were significant differences between tree species diversity in gaps and that under canopy (p<0.01).In terms of Shannon-Wiener index,evenness index,and abundance index,the biodiversity in gap community were higher than those under forest canopy in regeneration layer.In terms of Simpson's dominance index,the dominance of certain species in the regeneration layer increased from gaps to closed canopy (p<0.01).In contrast,trends of biodiversity changes of succession layer in gaps and under closed canopy were opposite.Tree species diversity of different layers reacted directly to the change of gap size class.For example,Shannon-Wiener index and abundance index is higher and Simpson's dominance index is the lowest in succession layer of medium-size gap (100-250 m2) in the broad-leaved Korean pine forest of Changbai Mountains.Shannon-Wiener index reached the highest in a size of≥250 m2 and<100 m2,reached the lowest in a size of 200-250 m2 in the regeneration layer.Simpson's dominance index reached its maximum when the gap size was between 200 and 250m2.Generally,species of different layers reacted differently to the changes of gap size classes.The gap size class with more seedlings did not correspond to size class containing more medium-size trees.Tree species diversity indices in the two layers behaved reciprocally during the development process of forest gaps.

  1. Can Canopy Uptake Influence Nitrogen Acquisition and Allocation by Trees?

    Science.gov (United States)

    Nair, Richard; Perks, Mike; Mencuccini, Maurizio

    2015-04-01

    Nitrogen (N) fertilization due to atmospheric deposition of anthropogenic nitrogen (NDEP) may explain some of the net carbon (C) sink (0.6-0.7 Pg y-1) in temperate forests, but estimates of the additional C uptake due to atmospheric N additions (ΔCΔN) can vary by over an order of magnitude (~ 5 to 200 ΔCΔN). High estimates from several recent studies [e.g. Magnani (2007), Nature 447 848-850], deriving ΔCΔN from regional correlations between NDEP and measures of C uptake (such as eddy covariance -derived net ecosystem production, or forest inventory data) contradict estimates from other studies of 15N tracer applications added as fertilizer to the forest floor. A strong ΔCΔN effect requires nitrogen to be efficiently acquired by trees and allocated to high C:N, long-lived woody tissues, but these isotope experiments typically report relatively little (~ 20 %) of 15N added is found above-ground, with soil, often in a limited number of treatment events over relatively short periods of time. Excessive N deposition loads can induce negative physiological effects and limit the resulting ΔCΔN observed, and applying treatments to the soil may ignore the importance of canopy nitrogen uptake in overall forest nutrition. As canopies can directly take up nitrogen, the chronic, (relatively) low levels of ambient NDEP inputs from pollution may be acquired without some of the effects of heavy N loads, obtaining this N before it reaches the soil, and allowing canopies to substitute for, or supplement, edaphic N nutrition. The strength of this effect depends on how much N uptake can occur across the canopy under field conditions, and if this extra N supplies growth in woody tissues such as the stem, as well as the canopy. To test these ideas, we applied a low (~ 2.5 % above ambient NDEP) 15N treatment to Picea sitchensis saplings, targeting the soil or the canopy in monthly fertilizations for 16 months, and investigating 15N return in different age classes of biomass and

  2. TREE CANOPY COVER MAPPING USING LiDAR IN URBAN BARANGAYS OF CEBU CITY, CENTRAL PHILIPPINES

    OpenAIRE

    Ejares, J. A.; Violanda, R. R.; Diola, A. G.; Dy, D. T.; Otadoy, J. B.; R. E. S. Otadoy

    2016-01-01

    This paper investigates tree canopy cover mapping of urban barangays (smallest administrative division in the Philippines) in Cebu City using LiDAR (Light Detection and Ranging). Object-Based Image Analysis (OBIA) was used to extract tree canopy cover. Multi-resolution segmentation and a series of assign-class algorithm in eCognition software was also performed to extract different land features. Contextual features of tree canopies such as height, area, roundness, slope, length-width and ell...

  3. From gene trees to species trees II: Species tree inference in the deep coalescence model

    OpenAIRE

    Zhang, Louxin

    2010-01-01

    When gene copies are sampled from various species, the resulting gene tree might disagree with the containing species tree. The primary causes of gene tree and species tree discord include lineage sorting, horizontal gene transfer, and gene duplication and loss. Each of these events yields a different parsimony criterion for inferring the (containing) species tree from gene trees. With lineage sorting, species tree inference is to find the tree minimizing extra gene lineages that had to coexi...

  4. Abundance of green tree frogs and insects in artificial canopy gaps in a bottomland hardwood forest.

    Energy Technology Data Exchange (ETDEWEB)

    Horn, Scott; Hanula, James L.; Ulyshen, Michael D.; Kilgo, John C.

    2005-01-01

    Horn, Scott, James L. Hanula, Michael D. Ulyshen, and John C. Kilgo. 2005. Abundance of green tree frogs and insects in artificial canopy gaps in a bottomland hardwood forest. Am. Midl. Nat. 153:321-326. Abstract: We found more green tree frogs (Hyla cinerea) in canopy gaps than in closed canopy forest. Of the 331 green tree frogs observed, 88% were in canopy gaps. Likewise, higher numbers and biomasses of insects were captured in the open gap habitat. Flies were the most commonly collected insect group accounting for 54% of the total capture. These data suggest that one reason green tree frogs were more abundant in canopy gaps was the increased availability of prey and that small canopy gaps provide early successional habitats that are beneficial to green tree frog populations.

  5. SPATIAL CONTAGIOUSNESS OF CANOPY DISTURBANCE IN TROPICAL RAIN FOREST : AN INDIVIDUAL-TREE-BASED TEST

    NARCIS (Netherlands)

    Jansen, Patrick A.; Van Der Meer, Peter J.; Bongers, Frans

    2008-01-01

    Spatial contagiousness of canopy dynamics-the tendency of canopy disturbances to occur nearby existing canopy openings due to an elevated risk of tree fall around gaps-has been demonstrated in many temperate-zone forests, but only inferentially for tropical forests. Hypothesized mechanisms increasin

  6. 100-Meter Resolution Tree Canopy of the Conterminous United States - Direct Download

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — This map layer contains tree canopy data for the conterminous United States, in an Albers Equal-Area Conic projection and at a resolution of 100 meters. The tree...

  7. Automated detection of branch dimensions in woody skeletons of leafless fruit tree canopies

    NARCIS (Netherlands)

    Bucksch, A.; Fleck, S.

    2009-01-01

    Light driven physiological processes of tree canopies need to be modelled based on detailed 3Dcanopy structure – we explore the possibilities offered by terrestrial LIDAR to automatically represent woody skeletons of leafless trees as a basis for adequate models of canopy structure. The automatic ev

  8. Abundance of Green Tree Frogs and Insects in Artificial Canopy Gaps in a Bottomland Hardwood Forest.

    Energy Technology Data Exchange (ETDEWEB)

    Horn, Scott; Hanula, James, L.; Ulyshen, Michael D.; Kilgo, John, C.

    2005-04-01

    ABSTRACT - We found more green tree frogs ( Hyla cinerea) n canopv gaps than in closed canopy forest. Of the 331 green tree frogs observed, 88% were in canopv gaps. Likewise, higher numbers and biomasses of insects were captured in the open gap habitat Flies were the most commonlv collected insect group accounting for 54% of the total capture. These data suggest that one reason green tree frogs were more abundant in canopy gaps was the increased availability of prey and that small canopy gaps provide early successional habitats that are beneficial to green tree frog populations.

  9. Potential of Individual and Cluster Tree Cooling Effect Performances Through Tree Canopy Density Model Evaluation in Improving Urban Microclimate

    OpenAIRE

    Mohd Fairuz Shahidan

    2015-01-01

    Technically, trees can provide cooling effect and able to reduce ambient temperature in its own way. This paper investigates the potential of individual and cluster tree cooling effect performances in improving urban microclimate through the evaluation of urban trees canopy density. The evaluation is based on the actual measurement of Leaf Area Index (LAI) and Leaf Area Density (LAD) and uses tested computer simulation tools ENVI-met. The study found that each tree has different capabilities ...

  10. Urban Tree Canopy and Asthma, Wheeze, Rhinitis, and Allergic Sensitization to Tree Pollen in a New York City Birth Cohort

    OpenAIRE

    Lovasi, Gina S.; O’Neil-Dunne, Jarlath P.M.; Lu, Jacqueline W.T.; Sheehan, Daniel; Perzanowski, Matthew S.; MacFaden, Sean W.; King, Kristen L.; Matte, Thomas; Miller, Rachel L.; Hoepner, Lori A.; Perera, Frederica P.; Rundle, Andrew

    2013-01-01

    Background: Urban landscape elements, particularly trees, have the potential to affect airflow, air quality, and production of aeroallergens. Several large-scale urban tree planting projects have sought to promote respiratory health, yet evidence linking tree cover to human health is limited. Objectives: We sought to investigate the association of tree canopy cover with subsequent development of childhood asthma, wheeze, rhinitis, and allergic sensitization. Methods: Birth cohort study data w...

  11. MAPPING URBAN TREE CANOPY COVER USING FUSED AIRBORNE LIDAR AND SATELLITE IMAGERY DATA

    OpenAIRE

    Parmehr, Ebadat G.; Amati, Marco; Fraser, Clive S.

    2016-01-01

    Urban green spaces, particularly urban trees, play a key role in enhancing the liveability of cities. The availability of accurate and up-to-date maps of tree canopy cover is important for sustainable development of urban green spaces. LiDAR point clouds are widely used for the mapping of buildings and trees, and several LiDAR point cloud classification techniques have been proposed for automatic mapping. However, the effectiveness of point cloud classification techniques for automated tree e...

  12. Attributes for NHDPlus Catchments (Version 1.1) for the Conterminous United States: NLCD 2001 Tree Canopy

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — This data set represents the mean percentage of tree canopy from the Canopy Layer of the National Land Cover Dataset 2001, (LaMotte and Wieczorek, 2010), compiled...

  13. Dense understory dwarf bamboo alters the retention of canopy tree seeds

    Science.gov (United States)

    Qian, Feng; Zhang, Tengda; Guo, Qinxue; Tao, Jianping

    2016-05-01

    Tree seed retention is thought to be an important factor in the process of forest community regeneration. Although dense understory dwarf bamboo has been considered to have serious negative effects on the regeneration of forest community species, little attention has been paid to the relationship between dwarf bamboo and seed retention. In a field experiment we manipulated the density of Fargesia decurvata, a common understory dwarf bamboo, to investigate the retention of seeds from five canopy tree species in an evergreen and deciduous broad-leaved mixed forest in Jinfoshan National Nature Reserve, SW China. We found that the median survival time and retention ratio of seeds increased with the increase in bamboo density. Fauna discriminately altered seed retention in bamboo groves of different densities. Arthropods reduced seed survival the most, and seeds removed decreased with increasing bamboo density. Birds removed or ate more seeds in groves of medium bamboo density and consumed fewer seeds in dense or sparse bamboo habitats. Rodents removed a greater number of large and highly profitable seeds in dense bamboo groves but more small and thin-husked seeds in sparse bamboo groves. Seed characteristics, including seed size, seed mass and seed profitability, were important factors affecting seed retention. The results suggested that dense understory dwarf bamboo not only increased seeds concealment and reduced the probability and speed of seed removal but also influenced the trade-off between predation and risk of animal predatory strategies, thereby impacting the quantity and composition of surviving seeds. Our results also indicated that dense understory dwarf bamboo and various seed characteristics can provide good opportunities for seed storage and seed germination and has a potential positive effect on canopy tree regeneration.

  14. Potential of Individual and Cluster Tree Cooling Effect Performances Through Tree Canopy Density Model Evaluation in Improving Urban Microclimate

    Directory of Open Access Journals (Sweden)

    Mohd Fairuz Shahidan

    2015-08-01

    Full Text Available Technically, trees can provide cooling effect and able to reduce ambient temperature in its own way. This paper investigates the potential of individual and cluster tree cooling effect performances in improving urban microclimate through the evaluation of urban trees canopy density. The evaluation is based on the actual measurement of Leaf Area Index (LAI and Leaf Area Density (LAD and uses tested computer simulation tools ENVI-met. The study found that each tree has different capabilities in modifying each microclimate variables. However, it was revealed that the optimum effect of cooling of each tree was found during the hottest day to takes place approximately at 15:00 hours when the sun is overhead and solar angle height is close to 90°. Besides, trees with higher densities such as Ficus benjamina (i.e. LAI 9.7, LAD > 1.5 showed a remarkable reduction in comparison to the other loose density trees. It is also revealed that the implementation of cluster tree planting at larger scale could maximize the effects of cooling. Nevertheless, the downside of implementing high tree density could create a reduction of 63% of wind speed that might possibly influence the air movement in urban areas due to the drag force of tree canopy. The study concluded that the performance of tree cooling effect is well correlated with tree canopy density and it is also suggested the optimum cooling effect could achieved by higher tree density (mean LAD > 1.5 and larger tree quantities with tree cluster planting.

  15. Estimating fluorescence emission of city trees in Valencia: from leaf to canopy level

    Science.gov (United States)

    Van Wittenberghe, S.; Alonso, L.; Verrelst, J.; Veroustraete, F.; Valcke, R.; Moreno, J.; Samson, R.

    2012-04-01

    Air pollutant concentrations in cities can be very high due to the heavy traffic load. Also, these concentrations vary on a small scale due to differences in traffic density, street layout and the surrounding land uses, leading to local hot-spots for air pollution. These different growing environments can result in a different stress outcome for city trees, which can be measured at different scales. Leaf radiative transfer characteristics such as spectral reflectance and sun-induced chlorophyll fluorescence (F) give information about the physiological status of the leaf and can be measured both at the leaf and canopy scales. The goal of the BIOHYPE project is to develop a passive biomonitoring methodology from leaf to canopy scale based on fluorescence and reflectance parameters as indicators for leaf physiological stress. Field and flight campaigns were set in Valencia during the summer of 2011. Four tree species with different leaf characteristics were selected at 10 locations in the city with different traffic densities. Fluorescence emission was measured with an ASD FieldSpec spectroradiometer in combination with the Fluowat leafclip, a portable device to measure leaf reflectance, transmittance and fluorescence emission under natural conditions. Airborne images were acquired using a CASI-1500 VNIR hyperspectral imager in tandem with an AHS system for SWIR-TIR. Besides fluorescence, the following parameters have been measured and analyzed at leaf level: optical properties, chlorophyll content (Chl), water content and magnetic properties of deposited pollution dust. In this work, relationships of fluorescence with location (i.e. traffic density), pollution and chlorophyll content have been explored. At leaf level, first results suggest that the up- and down-ward total F yields are related to location for two of the four species, while the fluorescence peaks and their ratios showed a larger influence of location. The ratio F687/F741 for both down- and upward

  16. Mapping Urban Tree Canopy Cover Using Fused Airborne LIDAR and Satellite Imagery Data

    Science.gov (United States)

    Parmehr, Ebadat G.; Amati, Marco; Fraser, Clive S.

    2016-06-01

    Urban green spaces, particularly urban trees, play a key role in enhancing the liveability of cities. The availability of accurate and up-to-date maps of tree canopy cover is important for sustainable development of urban green spaces. LiDAR point clouds are widely used for the mapping of buildings and trees, and several LiDAR point cloud classification techniques have been proposed for automatic mapping. However, the effectiveness of point cloud classification techniques for automated tree extraction from LiDAR data can be impacted to the point of failure by the complexity of tree canopy shapes in urban areas. Multispectral imagery, which provides complementary information to LiDAR data, can improve point cloud classification quality. This paper proposes a reliable method for the extraction of tree canopy cover from fused LiDAR point cloud and multispectral satellite imagery data. The proposed method initially associates each LiDAR point with spectral information from the co-registered satellite imagery data. It calculates the normalised difference vegetation index (NDVI) value for each LiDAR point and corrects tree points which have been misclassified as buildings. Then, region growing of tree points, taking the NDVI value into account, is applied. Finally, the LiDAR points classified as tree points are utilised to generate a canopy cover map. The performance of the proposed tree canopy cover mapping method is experimentally evaluated on a data set of airborne LiDAR and WorldView 2 imagery covering a suburb in Melbourne, Australia.

  17. Tree-growth analyses to estimate tree species' drought tolerance

    NARCIS (Netherlands)

    Eilmann, B.; Rigling, A.

    2012-01-01

    Climate change is challenging forestry management and practices. Among other things, tree species with the ability to cope with more extreme climate conditions have to be identified. However, while environmental factors may severely limit tree growth or even cause tree death, assessing a tree specie

  18. An application of the lottery competition model to a montane rainforest community of two canopy trees, ohia (Metrosideros polymorpha) and koa (Acacia koa) on Mauna Loa, Hawaii

    Science.gov (United States)

    Hatfield, J.S.; Link, W.A.; Dawson, D.K.; Lindquist, E.L.

    1992-01-01

    This rainforest occurs on Mauna Loa at 1500-2000 m elevation. Earthwatch volunteers, studying the habitat of 8 native forest bird species (3 endangered), identified 2382 living canopy trees, and 99 dead trees, on 68 study plots, 400 m2 each. Ohia made up 88% of the canopy; koa was 12%. The two-species lottery competition model, a stochastic model in which coexistence of species results from variation in recruitment and death rates, predicts a quadratic-beta distribution for the proportion of space occupied by one species. A discrete version was fit to the live tree data and a likelihood ratio test (p=0.02) was used to test if the mean death rates were equal. This test was corroborated by a contingency table analysis (p=0.03) based on dead trees. Parameter estimates from the two analyses were similar.

  19. Partitioning of soil water among canopy trees during a soil desiccation period in a temperate mixed forest

    Directory of Open Access Journals (Sweden)

    M. Meißner

    2012-05-01

    Full Text Available Complementary resource use is considered an important mechanism in the study of biodiversity effects. Here we explore how species identity, species mixture and tree size influence the vertical partitioning of soil water among canopy trees during a soil desiccation period. In the Hainich forest, Germany, the species Fagus sylvatica, Tilia sp. and Fraxinus excelsior were studied in single- and three-species mixed clusters, each consisting of three co-dominant trees situated within a larger mixed forest stand. Vertical soil water uptake depth was assessed by analyzing the hydrogen stable isotope composition (deuterium, δ D of water from depth intervals throughout the soil profile and in tree xylem water. For single species clusters, a mixing model suggested that Fagus distinctively drew water from soil depths of 0.3–0.5 m, Tilia from 0.3–0.5 m and 0.5–0.7 m and Fraxinus mainly used water from 0.5–0.7 m. In mixed clusters, the uptake patterns of Fagus and Tilia were similar to those of the single-species clusters (mainly uptake form 0.3–0.5 m, but Fraxinus showed a different uptake pattern. Fraxinus in mixture had a somewhat homogenously distributed uptake over the soil depths 0.2–0.7 m. For single species clusters, there was no correlation between main soil water uptake depth and tree diameter, irrespective of variations in tree size. In contrast, for mixed clusters there was a significant decrease in the main uptake depth with increasing tree size (P<0.001, R2adj = 0.73, irrespective of species mix. In consequence, soil water partitioning was strongest where species were mixed and tree size varied. We further analyzed whether single and mixed-species clusters differed in the level of water uptake, e.g. due to complementarity, but our soil water budgeting did not indicate any such differences. A possible explanation might be that the

  20. Contrasting seasonal leaf habits of canopy trees between tropical dry-deciduous and evergreen forests in Thailand.

    Science.gov (United States)

    Ishida, Atsushi; Diloksumpun, Sapit; Ladpala, Phanumard; Staporn, Duriya; Panuthai, Samreong; Gamo, Minoru; Yazaki, Kenichi; Ishizuka, Moriyoshi; Puangchit, Ladawan

    2006-05-01

    We compared differences in leaf properties, leaf gas exchange and photochemical properties between drought-deciduous and evergreen trees in tropical dry forests, where soil nutrients differed but rainfall was similar. Three canopy trees (Shorea siamensis Miq., Xylia xylocarpa (Roxb.) W. Theob. and Vitex peduncularis Wall. ex Schauer) in a drought-deciduous forest and a canopy tree (Hopea ferrea Lanessan) in an evergreen forest were selected. Soil nutrient availability is lower in the evergreen forest than in the deciduous forest. Compared with the evergreen tree, the deciduous trees had shorter leaf life spans, lower leaf masses per area, higher leaf mass-based nitrogen (N) contents, higher leaf mass-based photosynthetic rates (mass-based P(n)), higher leaf N-based P(n), higher daily maximum stomatal conductance (g(s)) and wider conduits in wood xylem. Mass-based P(n) decreased from the wet to the dry season for all species. Following onset of the dry season, daily maximum g(s) and sensitivity of g(s) to leaf-to-air vapor pressure deficit remained relatively unchanged in the deciduous trees, whereas both properties decreased in the evergreen tree during the dry season. Photochemical capacity and non-photochemical quenching (NPQ) of photosystem II (PSII) also remained relatively unchanged in the deciduous trees even after the onset of the dry season. In contrast, photochemical capacity decreased and NPQ increased in the evergreen tree during the dry season, indicating that the leaves coped with prolonged drought by down-regulating PSII. Thus, the drought-avoidant deciduous species were characterized by high N allocation for leaf carbon assimilation, high water use and photoinhibition avoidance, whereas the drought-tolerant evergreen was characterized by low N allocation for leaf carbon assimilation, conservative water use and photoinhibition tolerance. PMID:16452078

  1. Unifying constructal theory of tree roots, canopies and forests.

    Science.gov (United States)

    Bejan, A; Lorente, S; Lee, J

    2008-10-01

    Here, we show that the most basic features of tree and forest architecture can be put on a unifying theoretical basis, which is provided by the constructal law. Key is the integrative approach to understanding the emergence of "designedness" in nature. Trees and forests are viewed as integral components (along with dendritic river basins, aerodynamic raindrops, and atmospheric and oceanic circulation) of the much greater global architecture that facilitates the cyclical flow of water in nature (Fig. 1) and the flow of stresses between wind and ground. Theoretical features derived in this paper are: the tapered shape of the root and longitudinally uniform diameter and density of internal flow tubes, the near-conical shape of tree trunks and branches, the proportionality between tree length and wood mass raised to 1/3, the proportionality between total water mass flow rate and tree length, the proportionality between the tree flow conductance and the tree length scale raised to a power between 1 and 2, the existence of forest floor plans that maximize ground-air flow access, the proportionality between the length scale of the tree and its rank raised to a power between -1 and -1/2, and the inverse proportionality between the tree size and number of trees of the same size. This paper further shows that there exists an optimal ratio of leaf volume divided by total tree volume, trees of the same size must have a larger wood volume fraction in windy climates, and larger trees must pack more wood per unit of tree volume than smaller trees. Comparisons with empirical correlations and formulas based on ad hoc models are provided. This theory predicts classical notions such as Leonardo's rule, Huber's rule, Zipf's distribution, and the Fibonacci sequence. The difference between modeling (description) and theory (prediction) is brought into evidence.

  2. Regional Estimates of Drought-Induced Tree Canopy Loss across Texas

    Science.gov (United States)

    Schwantes, A.; Swenson, J. J.; González-Roglich, M.; Johnson, D. M.; Domec, J. C.; Jackson, R. B.

    2015-12-01

    The severe drought of 2011 killed millions of trees across the state of Texas. Drought-induced tree-mortality can have significant impacts to carbon cycling, regional biophysics, and community composition. We quantified canopy cover loss across the state using remotely sensed imagery from before and after the drought at multiple scales. First, we classified ~200 orthophotos (1-m spatial resolution) from the National Agriculture Imagery Program, using a supervised maximum likelihood classification. Area of canopy cover loss in these classifications was highly correlated (R2 = 0.8) with ground estimates of canopy cover loss, measured in 74 plots across 15 different sites in Texas. These 1-m orthophoto classifications were then used to calibrate and validate coarser scale (30-m) Landsat imagery to create wall-to-wall tree canopy cover loss maps across the state of Texas. We quantified percent dead and live canopy within each pixel of Landsat to create continuous maps of dead and live tree cover, using two approaches: (1) a zero-inflated beta distribution model and (2) a random forest algorithm. Widespread canopy loss occurred across all the major natural systems of Texas, with the Edwards Plateau region most affected. In this region, on average, 10% of the forested area was lost due to the 2011 drought. We also identified climatic thresholds that controlled the spatial distribution of tree canopy loss across the state. However, surprisingly, there were many local hot spots of canopy loss, suggesting that not only climatic factors could explain the spatial patterns of canopy loss, but rather other factors related to soil, landscape, management, and stand density also likely played a role. As increases in extreme droughts are predicted to occur with climate change, it will become important to define methods that can detect associated drought-induced tree mortality across large regions. These maps could then be used (1) to quantify impacts to carbon cycling and regional

  3. The inference of gene trees with species trees.

    Science.gov (United States)

    Szöllősi, Gergely J; Tannier, Eric; Daubin, Vincent; Boussau, Bastien

    2015-01-01

    This article reviews the various models that have been used to describe the relationships between gene trees and species trees. Molecular phylogeny has focused mainly on improving models for the reconstruction of gene trees based on sequence alignments. Yet, most phylogeneticists seek to reveal the history of species. Although the histories of genes and species are tightly linked, they are seldom identical, because genes duplicate, are lost or horizontally transferred, and because alleles can coexist in populations for periods that may span several speciation events. Building models describing the relationship between gene and species trees can thus improve the reconstruction of gene trees when a species tree is known, and vice versa. Several approaches have been proposed to solve the problem in one direction or the other, but in general neither gene trees nor species trees are known. Only a few studies have attempted to jointly infer gene trees and species trees. These models account for gene duplication and loss, transfer or incomplete lineage sorting. Some of them consider several types of events together, but none exists currently that considers the full repertoire of processes that generate gene trees along the species tree. Simulations as well as empirical studies on genomic data show that combining gene tree-species tree models with models of sequence evolution improves gene tree reconstruction. In turn, these better gene trees provide a more reliable basis for studying genome evolution or reconstructing ancestral chromosomes and ancestral gene sequences. We predict that gene tree-species tree methods that can deal with genomic data sets will be instrumental to advancing our understanding of genomic evolution.

  4. Trees grow on money: urban tree canopy cover and environmental justice.

    Directory of Open Access Journals (Sweden)

    Kirsten Schwarz

    Full Text Available This study examines the distributional equity of urban tree canopy (UTC cover for Baltimore, MD, Los Angeles, CA, New York, NY, Philadelphia, PA, Raleigh, NC, Sacramento, CA, and Washington, D.C. using high spatial resolution land cover data and census data. Data are analyzed at the Census Block Group levels using Spearman's correlation, ordinary least squares regression (OLS, and a spatial autoregressive model (SAR. Across all cities there is a strong positive correlation between UTC cover and median household income. Negative correlations between race and UTC cover exist in bivariate models for some cities, but they are generally not observed using multivariate regressions that include additional variables on income, education, and housing age. SAR models result in higher r-square values compared to the OLS models across all cities, suggesting that spatial autocorrelation is an important feature of our data. Similarities among cities can be found based on shared characteristics of climate, race/ethnicity, and size. Our findings suggest that a suite of variables, including income, contribute to the distribution of UTC cover. These findings can help target simultaneous strategies for UTC goals and environmental justice concerns.

  5. Experimental study on determining factors of canopy interception using artificial Christmas trees

    Science.gov (United States)

    Murakami, Shigeki; Toba, Tae

    2013-04-01

    Evaporation of canopy interception (CI) is a major component of water balance in forested areas. Theoretically, the evaporation amount is dependent on the tree height, i.e. aerodynamic roughness. Nevertheless, the theory does not always explain the observed results and the observational fact that CI during rainfall is proportional to the rainfall intensity makes the problem paradoxical (Murakami, 2006). The objective of this study is to try to find the determining factors of CI in terms of the stand structure using artificial Christmas trees that is easy to modify the height and tree density. Two kinds of artificial Christmas trees were used: a) 65 cm high with the maximum canopy diameter of 30 cm, and b) 150 cm high with the greatest canopy diameter of 75 cm. We set those trees on three trays and left them outside to measure CI using natural rainfall. Artificial trees a) were set on Tray #1 and #2 measuring 178-cm-square. Artificial trees b) were fixed on Tray #3 with a size of 360-cm-square. Tray #1 was a control and the stand structure was unchanged throughout the experiment, i.e. tree height was 65 cm with 41 stems on the tray. Three experimental runs were conducted; Run #1 and #2 were to compare the effect of stem length (tree height) on CI. Run #3 was to evaluate the effect of thinning. The initial number of trees on each tray was 41 (Run #1 and #2), and it was reduced to 25 after thinning for Tray #2 and #3 (Run #3). At Run #1 tree heights of Tray #2 and #3 were 90 cm and 150 cm (original), respectively, and at Run #2 and #3 they were 120 cm and 240 cm, respectively. In Tray #1 canopy interception rate (IR, the ratio of CI to gross rainfall) was constant (12.1% to 13.3%). IR increased with tree height for each tree, i.e. a) and b). In Tray #2, i.e. tree a), IR increased from 19.7% to 22.8% after thinning, while in Tray #3, i.e. tree b), it diminished from 20.0% to 13.8%. Preliminary analysis showed that hourly CI is clearly proportional to hourly rainfall

  6. Tree Canopy Cover Mapping Using LiDAR in Urban Barangays of Cebu City, Central Philippines

    Science.gov (United States)

    Ejares, J. A.; Violanda, R. R.; Diola, A. G.; Dy, D. T.; Otadoy, J. B.; Otadoy, R. E. S.

    2016-06-01

    This paper investigates tree canopy cover mapping of urban barangays (smallest administrative division in the Philippines) in Cebu City using LiDAR (Light Detection and Ranging). Object-Based Image Analysis (OBIA) was used to extract tree canopy cover. Multi-resolution segmentation and a series of assign-class algorithm in eCognition software was also performed to extract different land features. Contextual features of tree canopies such as height, area, roundness, slope, length-width and elliptic fit were also evaluated. The results showed that at the time the LiDAR data was collected (June 24, 2014), the tree cover was around 25.11 % (or 15,674,341.8 m2) of the city's urban barangays (or 62,426,064.6 m2). Among all urban barangays in Cebu City, Barangay Busay had the highest cover (55.79 %) while barangay Suba had the lowest (0.8 %). The 16 barangays with less than 10 % tree cover were generally located in the coastal area, presumably due to accelerated urbanization. Thirty-one barangays have tree cover ranging from 10.59--27.3 %. Only 3 barangays (i.e., Lahug, Talamban, and Busay) have tree cover greater than 30 %. The overall accuracy of the analysis was 96.6 % with the Kappa Index of Agreement or KIA of 0.9. From the study, a grouping can be made of the city's urban barangays with regards to tree cover. The grouping will be useful to urban planners not only in allocating budget to the tree planting program of the city but also in planning and creation of urban parks and playgrounds.

  7. TREE CANOPY COVER MAPPING USING LiDAR IN URBAN BARANGAYS OF CEBU CITY, CENTRAL PHILIPPINES

    Directory of Open Access Journals (Sweden)

    J. A. Ejares

    2016-06-01

    Full Text Available This paper investigates tree canopy cover mapping of urban barangays (smallest administrative division in the Philippines in Cebu City using LiDAR (Light Detection and Ranging. Object-Based Image Analysis (OBIA was used to extract tree canopy cover. Multi-resolution segmentation and a series of assign-class algorithm in eCognition software was also performed to extract different land features. Contextual features of tree canopies such as height, area, roundness, slope, length-width and elliptic fit were also evaluated. The results showed that at the time the LiDAR data was collected (June 24, 2014, the tree cover was around 25.11 % (or 15,674,341.8 m2 of the city’s urban barangays (or 62,426,064.6 m2. Among all urban barangays in Cebu City, Barangay Busay had the highest cover (55.79 % while barangay Suba had the lowest (0.8 %. The 16 barangays with less than 10 % tree cover were generally located in the coastal area, presumably due to accelerated urbanization. Thirty-one barangays have tree cover ranging from 10.59–-27.3 %. Only 3 barangays (i.e., Lahug, Talamban, and Busay have tree cover greater than 30 %. The overall accuracy of the analysis was 96.6 % with the Kappa Index of Agreement or KIA of 0.9. From the study, a grouping can be made of the city’s urban barangays with regards to tree cover. The grouping will be useful to urban planners not only in allocating budget to the tree planting program of the city but also in planning and creation of urban parks and playgrounds.

  8. Variation in foliar respiration and wood CO2 efflux rates among species and canopy layers in a wet tropical forest.

    Science.gov (United States)

    Asao, Shinichi; Bedoya-Arrieta, Ricardo; Ryan, Michael G

    2015-02-01

    As tropical forests respond to environmental change, autotrophic respiration may consume a greater proportion of carbon fixed in photosynthesis at the expense of growth, potentially turning the forests into a carbon source. Predicting such a response requires that we measure and place autotrophic respiration in a complete carbon budget, but extrapolating measurements of autotrophic respiration from chambers to ecosystem remains a challenge. High plant species diversity and complex canopy structure may cause respiration rates to vary and measurements that do not account for this complexity may introduce bias in extrapolation more detrimental than uncertainty. Using experimental plantations of four native tree species with two canopy layers, we examined whether species and canopy layers vary in foliar respiration and wood CO2 efflux and whether the variation relates to commonly used scalars of mass, nitrogen (N), photosynthetic capacity and wood size. Foliar respiration rate varied threefold between canopy layers, ∼0.74 μmol m(-2) s(-1) in the overstory and ∼0.25 μmol m(-2) s(-1) in the understory, but little among species. Leaf mass per area, N and photosynthetic capacity explained some of the variation, but height explained more. Chamber measurements of foliar respiration thus can be extrapolated to the canopy with rates and leaf area specific to each canopy layer or height class. If area-based rates are sampled across canopy layers, the area-based rate may be regressed against leaf mass per area to derive the slope (per mass rate) to extrapolate to the canopy using the total leaf mass. Wood CO2 efflux varied 1.0-1.6 μmol m(-2) s(-1) for overstory trees and 0.6-0.9 μmol m(-2) s(-1) for understory species. The variation in wood CO2 efflux rate was mostly related to wood size, and little to species, canopy layer or height. Mean wood CO2 efflux rate per surface area, derived by regressing CO2 efflux per mass against the ratio of surface

  9. Functional diversity of photosynthetic light use of sixteen vascular epiphyte species under fluctuating irradiance in the canopy of a giant Virola michelii (Myristicaceae tree in the tropical lowland forest of French Guyana

    Directory of Open Access Journals (Sweden)

    Uwe eRascher

    2012-01-01

    Full Text Available Here we present the first study, in which a large number of different vascular epiphyte species were measured for their photosynthetic performance in the natural environment of their phorophyte in the lowland rainforest of French Guyana. More than 70 epiphyte species covered the host tree in a dense cover. Of these, the photosynthesis of 16 abundant species was analyzed intensely over several months. Moreover, the light environment was characterized with newly developed light sensors that recorded continuously and with high temporal resolution light intensity next to the epiphytes. Light intensity was highly fluctuating and showed great site specific spatio-temporal variations of photosynthetic photon flux. Using a novel computer routine we quantified the integrated light intensity the epiphytes were exposed to in a 3-hour window and we related this light intensity to measurements of the actual photosynthetic status. It could be shown that the photosynthetic apparatus of the epiphytes was well adapted to the quickly changing light conditions. Some of the epiphytes were chronically photoinhibited at pre-dawn and significant acute photoinhibition, expressed by a reduction of potential quantum efficiency (Fv/Fm30’, was observed during the day. By correlating (Fv/Fm30’ to the integrated and weighted light intensity perceived during the previous 3 hours, it became clear that acute photoinhibition was related to light environment prior to the measurements. Additionally photosynthetic performance was not determined by rain events, with the exception of an Aechmea species. This holds true for all the other 15 species of this study and we thus conclude that actual photosynthesis of these tropical epiphytes was determined by the specific and fluctuating light conditions of their microhabitat and cannot be simply attributed to light adapted ancestors.

  10. A tree canopy height delineation method based on Morphological Reconstruction—Open Crown Decomposition

    Science.gov (United States)

    Liu, Q.; Jing, L.; Li, Y.; Tang, Y.; Li, H.; Lin, Q.

    2016-04-01

    For the purpose of forest management, high resolution LIDAR and optical remote sensing imageries are used for treetop detection, tree crown delineation, and classification. The purpose of this study is to develop a self-adjusted dominant scales calculation method and a new crown horizontal cutting method of tree canopy height model (CHM) to detect and delineate tree crowns from LIDAR, under the hypothesis that a treetop is radiometric or altitudinal maximum and tree crowns consist of multi-scale branches. The major concept of the method is to develop an automatic selecting strategy of feature scale on CHM, and a multi-scale morphological reconstruction-open crown decomposition (MRCD) to get morphological multi-scale features of CHM by: cutting CHM from treetop to the ground; analysing and refining the dominant multiple scales with differential horizontal profiles to get treetops; segmenting LiDAR CHM using watershed a segmentation approach marked with MRCD treetops. This method has solved the problems of false detection of CHM side-surface extracted by the traditional morphological opening canopy segment (MOCS) method. The novel MRCD delineates more accurate and quantitative multi-scale features of CHM, and enables more accurate detection and segmentation of treetops and crown. Besides, the MRCD method can also be extended to high optical remote sensing tree crown extraction. In an experiment on aerial LiDAR CHM of a forest of multi-scale tree crowns, the proposed method yielded high-quality tree crown maps.

  11. Gene tree correction for reconciliation and species tree inference

    Directory of Open Access Journals (Sweden)

    Swenson Krister M

    2012-11-01

    Full Text Available Abstract Background Reconciliation is the commonly used method for inferring the evolutionary scenario for a gene family. It consists in “embedding” inferred gene trees into a known species tree, revealing the evolution of the gene family by duplications and losses. When a species tree is not known, a natural algorithmic problem is to infer a species tree from a set of gene trees, such that the corresponding reconciliation minimizes the number of duplications and/or losses. The main drawback of reconciliation is that the inferred evolutionary scenario is strongly dependent on the considered gene trees, as few misplaced leaves may lead to a completely different history, with significantly more duplications and losses. Results In this paper, we take advantage of certain gene trees’ properties in order to preprocess them for reconciliation or species tree inference. We flag certain duplication vertices of a gene tree, the “non-apparent duplication” (NAD vertices, as resulting from the misplacement of leaves. In the case of species tree inference, we develop a polynomial-time heuristic for removing the minimum number of species leading to a set of gene trees that exhibit no NAD vertices with respect to at least one species tree. In the case of reconciliation, we consider the optimization problem of removing the minimum number of leaves or species leading to a tree without any NAD vertex. We develop a polynomial-time algorithm that is exact for two special classes of gene trees, and show a good performance on simulated data sets in the general case.

  12. Semi-Supervised Methods to Identify Individual Crowns of Lowland Tropical Canopy Species Using Imaging Spectroscopy and LiDAR

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    Gregory P. Asner

    2012-08-01

    Full Text Available Our objective is to identify and map individuals of nine tree species in a Hawaiian lowland tropical forest by comparing the performance of a variety of semi-supervised classifiers. A method was adapted to process hyperspectral imagery, LiDAR intensity variables, and LiDAR-derived canopy height and use them to assess the identification accuracy. We found that semi-supervised Support Vector Machine classification using tensor summation kernel was superior to supervised classification, with demonstrable accuracy for at least eight out of nine species, and for all combinations of data types tested. We also found that the combination of hyperspectral imagery and LiDAR data usually improved species classification. Both LiDAR intensity and LiDAR canopy height proved useful for classification of certain species, but the improvements varied depending upon the species in question. Our results pave the way for target-species identification in tropical forests and other ecosystems.

  13. Canopy Fuel Load Mapping of Mediterranean Pine Sites Based on Individual Tree-Crown Delineation

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    Giorgos Mallinis

    2013-12-01

    Full Text Available This study presents an individual tree-crown-based approach for canopy fuel load estimation and mapping in two Mediterranean pine stands. Based on destructive sampling, an allometric equation was developed for the estimation of crown fuel weight considering only pine crown width, a tree characteristic that can be estimated from passive imagery. Two high resolution images were used originally for discriminating Aleppo and Calabrian pines crown regions through a geographic object based image analysis approach. Subsequently, the crown region images were segmented using a watershed segmentation algorithm and crown width was extracted. The overall accuracy of the tree crown isolation expressed through a perfect match between the reference and the delineated crowns was 34.00% for the Kassandra site and 48.11% for the Thessaloniki site, while the coefficient of determination between the ground measured and the satellite extracted crown width was 0.5. Canopy fuel load values estimated in the current study presented mean values from 1.29 ± 0.6 to 1.65 ± 0.7 kg/m2 similar to other conifers worldwide. Despite the modest accuracies attained in this first study of individual tree crown fuel load mapping, the combination of the allometric equations with satellite-based extracted crown width information, can contribute to the spatially explicit mapping of canopy fuel load in Mediterranean areas. These maps can be used among others in fire behavior prediction, in fuel reduction treatments prioritization and during active fire suppression.

  14. Species-specific associations between overstory and understory tree species in a semideciduous tropical forest

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    Flaviana Maluf Souza

    2015-03-01

    Full Text Available We investigated the occurrence of associations between overstory and understory tree species in a semideciduous tropical forest. We identified and measured all trees of nine canopy species with diameter at breast height ≥4.8 cm in a 10.24 ha plot and recorded all individuals beneath their canopies ("understory individuals" within the same diameter class. The total density of understory individuals did not significantly differ under different overstory species. One overstory species (Ceiba speciosa showed higher understory species richness compared with five other species. There was a strong positive association between three overstory species (Esenbeckia leiocarpa, Savia dictyocarpa, and C. speciosa and the density of seven understory species (Balfourodendron riedelianum, Chrysophyllum gonocarpum, E. leiocarpa, Holocalyx balansae, Machaerium stipitatum, Rhaminidium elaeocarpum, and S. dictyocarpa. These results probably reflect the outcome of a complex set of interactions including facilitation and competition, and further studies are necessary to better understand the magnitude and type of the effects of individual overstory species on understory species. The occurrence of species-specific associations shown here reinforces the importance of non-random processes in structuring plant communities and suggest that the influence of overstory species on understory species in high-diversity forests may be more significant than previously thought.

  15. Quantitative Analysis of Tree Species in Mixed Forests of Mandal Catchments, Garhwal Himalaya

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    Balwant KUMAR

    2012-06-01

    Full Text Available A total of 14 tree species were identified in the study sites, among which Quercus leucotrichophora Hook. F. (Banj oak, Rhododendron arboreum Smith (Burans, Lyonia ovalifolia Drude (Ayar and Pyrus pashia Buch-Hemp (Mehal are the predominant tree species. A quantitative analysis of tree species indicates that on the basis of their canopy cover, tree density and total base area, these study sites fall within the category of disturbed forest. The uncontrolled lopping for timber, firewood and leaf fodder and the absence of saplings and seedlings are some of the major factors responsible for the declining of forests in the Himalayan region.

  16. Tree architecture and forest canopy structure obtained from terrestrial LiDAR measurements

    Science.gov (United States)

    Hentschel, Reiner; Bittner, Sebastian; Ritter, Daniel; Priesack, Eckart

    2013-04-01

    ranging from single tree architectures to tree stand architecture of almost 100 deciduous trees of 25 meter height. The handling of the effects of self-shadowing and data gaps and the limits of the algorithm is discussed as well as the requirements for the laser scanner hardware and data acquisition. We show the use of the obtained tree and canopy architectures to simulate water uptake, water storage, and transpiration in combination with light absorption and leaf photosynthesis using a ray tracer model.

  17. The Inhibitory Effect of Rhododendron maximum L. (Ericaceae) Thickets on Mycorrhizal Colonization of Canopy Tree Seedlings

    OpenAIRE

    Walker, John F.

    1998-01-01

    THE INHIBITORY EFFECT OF RHODODENDRON MAXIMUM L. (ERICACEAE) THICKETS ON MYCORRHIZAL COLONIZATION OF CANOPY TREE SEEDLINGS John F. Walker (ABSTRACT) Thickets of Rhododendron maximum (Rm) in the southern Appalachians impose severe limitations on the regeneration of hardwood and coniferous seedlings. Interactions between Rm thickets and ectomycorrhizal colonization were examined to explain seedling inhibition. Experimental blocks were established in and out of Rm thickets in a mature,...

  18. Tree phyllosphere bacterial communities: exploring the magnitude of intra- and inter-individual variation among host species

    Science.gov (United States)

    Messier, Christian; Kembel, Steven W.

    2016-01-01

    Background The diversity and composition of the microbial community of tree leaves (the phyllosphere) varies among trees and host species and along spatial, temporal, and environmental gradients. Phyllosphere community variation within the canopy of an individual tree exists but the importance of this variation relative to among-tree and among-species variation is poorly understood. Sampling techniques employed for phyllosphere studies include picking leaves from one canopy location to mixing randomly selected leaves from throughout the canopy. In this context, our goal was to characterize the relative importance of intra-individual variation in phyllosphere communities across multiple species, and compare this variation to inter-individual and interspecific variation of phyllosphere epiphytic bacterial communities in a natural temperate forest in Quebec, Canada. Methods We targeted five dominant temperate forest tree species including angiosperms and gymnosperms: Acer saccharum, Acer rubrum, Betula papyrifera, Abies balsamea and Picea glauca. For one randomly selected tree of each species, we sampled microbial communities at six distinct canopy locations: bottom-canopy (1–2 m height), the four cardinal points of mid-canopy (2–4 m height), and the top-canopy (4–6 m height). We also collected bottom-canopy leaves from five additional trees from each species. Results Based on an analysis of bacterial community structure measured via Illumina sequencing of the bacterial 16S gene, we demonstrate that 65% of the intra-individual variation in leaf bacterial community structure could be attributed to the effect of inter-individual and inter-specific differences while the effect of canopy location was not significant. In comparison, host species identity explains 47% of inter-individual and inter-specific variation in leaf bacterial community structure followed by individual identity (32%) and canopy location (6%). Discussion Our results suggest that individual

  19. Trait Acclimation Mitigates Mortality Risks of Tropical Canopy Trees under Global Warming.

    Science.gov (United States)

    Sterck, Frank; Anten, Niels P R; Schieving, Feike; Zuidema, Pieter A

    2016-01-01

    There is a heated debate about the effect of global change on tropical forests. Many scientists predict large-scale tree mortality while others point to mitigating roles of CO2 fertilization and - the notoriously unknown - physiological trait acclimation of trees. In this opinion article we provided a first quantification of the potential of trait acclimation to mitigate the negative effects of warming on tropical canopy tree growth and survival. We applied a physiological tree growth model that incorporates trait acclimation through an optimization approach. Our model estimated the maximum effect of acclimation when trees optimize traits that are strongly plastic on a week to annual time scale (leaf photosynthetic capacity, total leaf area, stem sapwood area) to maximize carbon gain. We simulated tree carbon gain for temperatures (25-35°C) and ambient CO2 concentrations (390-800 ppm) predicted for the 21st century. Full trait acclimation increased simulated carbon gain by up to 10-20% and the maximum tolerated temperature by up to 2°C, thus reducing risks of tree death under predicted warming. Functional trait acclimation may thus increase the resilience of tropical trees to warming, but cannot prevent tree death during extremely hot and dry years at current CO2 levels. We call for incorporating trait acclimation in field and experimental studies of plant functional traits, and in models that predict responses of tropical forests to climate change.

  20. Trait Acclimation Mitigates Mortality Risks of Tropical Canopy Trees under Global Warming.

    Science.gov (United States)

    Sterck, Frank; Anten, Niels P R; Schieving, Feike; Zuidema, Pieter A

    2016-01-01

    There is a heated debate about the effect of global change on tropical forests. Many scientists predict large-scale tree mortality while others point to mitigating roles of CO2 fertilization and - the notoriously unknown - physiological trait acclimation of trees. In this opinion article we provided a first quantification of the potential of trait acclimation to mitigate the negative effects of warming on tropical canopy tree growth and survival. We applied a physiological tree growth model that incorporates trait acclimation through an optimization approach. Our model estimated the maximum effect of acclimation when trees optimize traits that are strongly plastic on a week to annual time scale (leaf photosynthetic capacity, total leaf area, stem sapwood area) to maximize carbon gain. We simulated tree carbon gain for temperatures (25-35°C) and ambient CO2 concentrations (390-800 ppm) predicted for the 21st century. Full trait acclimation increased simulated carbon gain by up to 10-20% and the maximum tolerated temperature by up to 2°C, thus reducing risks of tree death under predicted warming. Functional trait acclimation may thus increase the resilience of tropical trees to warming, but cannot prevent tree death during extremely hot and dry years at current CO2 levels. We call for incorporating trait acclimation in field and experimental studies of plant functional traits, and in models that predict responses of tropical forests to climate change. PMID:27242814

  1. Trait acclimation mitigates mortality risks of tropical canopy trees under global warming

    Directory of Open Access Journals (Sweden)

    Frank eSterck

    2016-05-01

    Full Text Available There is a heated debate about the effect of global change on tropical forests. Many scientists predict large-scale tree mortality while others point to mitigating roles of CO2 fertilization and – the notoriously unknown – physiological trait acclimation of trees. In this opinion article we provided a first quantification of the potential of trait acclimation to mitigate the negative effects of warming on tropical canopy tree growth and survival. We applied a physiological tree growth model that incorporates trait acclimation through an optimization approach. Our model estimated the maximum effect of acclimation when trees optimize traits that are strongly plastic on a week to annual time scale (leaf photosynthetic capacity, total leaf area, stem sapwood area to maximize carbon gain. We simulated tree carbon gain for temperatures (25-35ºC and ambient CO2 concentrations (390-800 ppm predicted for the 21st century. Full trait acclimation increased simulated carbon gain by up to 10-20% and the maximum tolerated temperature by up to 2ºC, thus reducing risks of tree death under predicted warming. Functional trait acclimation may thus increase the resilience of tropical trees to warming, but cannot prevent tree death during extremely hot and dry years at current CO2 levels. We call for incorporating trait acclimation in field and experimental studies of plant functional traits, and in models that predict responses of tropical forests to climate change.

  2. National Land Cover Database 2001 (NLCD01) Tree Canopy Layer Tile 1, Northwest United States: CNPY01_1

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — This 30-meter resolution data set represents the tree canopy layer for the conterminous United States for the 2001 time period. The data have been arranged into...

  3. National Land Cover Database 2001 (NLCD01) Tree Canopy Layer Tile 4, Southeast United States: CNPY01_4

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — This 30-meter resolution data set represents the tree canopy layer for the conterminous United States for the 2001 time period. The data have been arranged into...

  4. National Land Cover Database 2001 (NLCD01) Tree Canopy Layer Tile 2, Northeast United States: CNPY01_2

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — This 30-meter resolution data set represents the tree canopy layer for the conterminous United States for the 2001 time period. The data have been arranged into...

  5. National Land Cover Database 2001 (NLCD01) Tree Canopy Layer Tile 3, Southwest United States: CNPY01_3

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — This 30-meter resolution data set represents the tree canopy layer for the conterminous United States for the 2001 time period. The data have been arranged into...

  6. Semi-Supervised Methods to Identify Individual Crowns of Lowland Tropical Canopy Species Using Imaging Spectroscopy and LiDAR

    OpenAIRE

    Asner, Gregory P.; Jean-Baptiste Féret

    2012-01-01

    Our objective is to identify and map individuals of nine tree species in a Hawaiian lowland tropical forest by comparing the performance of a variety of semi-supervised classifiers. A method was adapted to process hyperspectral imagery, LiDAR intensity variables, and LiDAR-derived canopy height and use them to assess the identification accuracy. We found that semi-supervised Support Vector Machine classification using tensor summation kernel was superior to supervised classification, with dem...

  7. Slope variation and population structure of tree species from different ecological groups in South Brazil.

    Science.gov (United States)

    Bianchini, Edmilson; Garcia, Cristina C; Pimenta, José A; Torezan, José M D

    2010-09-01

    Size structure and spatial arrangement of 13 abundant tree species were determined in a riparian forest fragment in Paraná State, South Brazil (23°16'S and 51°01'W). The studied species were Aspidosperma polyneuron Müll. Arg., Astronium graveolens Jacq. and Gallesia integrifolia (Spreng) Harms (emergent species); Alseis floribunda Schott, Ruprechtia laxiflora Meisn. and Bougainvillea spectabilis Willd. (shade-intolerant canopy species); Machaerium paraguariense Hassl, Myroxylum peruiferum L. and Chrysophyllum gonocarpum (Mart. & Eichler ex Miq.) Engl. (shade-tolerant canopy species); Sorocea bonplandii (Baill.) Bürger, Trichilia casaretti C. Dc, Trichilia catigua A. Juss. and Actinostemon concolor (Spreng.) Müll. Arg. (understory small trees species). Height and diameter structures and basal area of species were analyzed. Spatial patterns and slope correlation were analyzed by Moran's / spatial autocorrelation coefficient and partial Mantel test, respectively. The emergent and small understory species showed the highest and the lowest variations in height, diameter and basal area. Size distribution differed among emergent species and also among canopy shade-intolerant species. The spatial pattern ranged among species in all groups, except in understory small tree species. The slope was correlated with spatial pattern for A. polyneuron, A. graveolens, A. floribunda, R. laxiflora, M. peruiferum and T. casaretti. The results indicated that most species occurred in specific places, suggesting that niche differentiation can be an important factor in structuring the tree community. PMID:21562693

  8. Light-related variation in sapling architecture of three shade-tolerant tree species of the Mexican rain forest

    NARCIS (Netherlands)

    Martinez-Sanchez, J.L.; Meave, J.; Bongers, F.

    2008-01-01

    The crown architecture of three shade-tolerant tree species (two subcanopy and one mid-canopy) was analyzed in relation to the light regime of the forest understorey. The aim was to examine to which extent shade-tolerant species variate in their crown architecture. Tree saplings (265) between 50 and

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

    International Nuclear Information System (INIS)

    Whole-tree O3 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 O3 flux. O3 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, O3 uptake to soil moisture and air humidity did not differ between species. Unifying findings at the whole-tree level will promote cause-effect based O3 risk assessment and modeling. - Sap flow-based assessment of whole-tree O3 uptake reflects similar responsiveness of canopy conductance and O3 uptake across contrasting tree species and site conditions

  10. An Analysis of Overstory Tree Canopy Cover in Sites Occupied by Native and Introduced Cottontails in the Northeastern United States with Recommendations for Habitat Management for New England Cottontail.

    Directory of Open Access Journals (Sweden)

    Bill Buffum

    Full Text Available The New England cottontail (Sylvilagus transitionalis is a high conservation priority in the Northeastern United States and has been listed as a candidate species under the Endangered Species Act. Loss of early successional habitat is the most common explanation for the decline of the species, which is considered to require habitat with dense low vegetation and limited overstory tree canopy. Federal and state wildlife agencies actively encourage landowners to create this habitat type by clearcutting blocks of forest. However, there are recent indications that the species also occupies sites with moderate overstory tree canopy cover. This is important because many landowners have negative views about clearcutting and are more willing to adopt silvicultural approaches that retain some overstory trees. Furthermore, it is possible that clearcuts with no overstory canopy cover may attract the eastern cottontail (S. floridanus, an introduced species with an expanding range. The objective of our study was to provide guidance for future efforts to create habitat that would be more favorable for New England cottontail than eastern cottontail in areas where the two species are sympatric. We analyzed canopy cover at 336 cottontail locations in five states using maximum entropy modelling and other statistical methods. We found that New England cottontail occupied sites with a mean overstory tree canopy cover of 58% (SE±1.36, and was less likely than eastern cottontail to occupy sites with lower overstory canopy cover and more likely to occupy sites with higher overstory canopy cover. Our findings suggest that silvicultural approaches that retain some overstory canopy cover may be appropriate for creating habitat for New England cottontail. We believe that our results will help inform critical management decisions for the conservation of New England cottontail, and that our methodology can be applied to analyses of habitat use of other critical wildlife

  11. An Analysis of Overstory Tree Canopy Cover in Sites Occupied by Native and Introduced Cottontails in the Northeastern United States with Recommendations for Habitat Management for New England Cottontail.

    Science.gov (United States)

    Buffum, Bill; McGreevy, Thomas J; Gottfried, Amy E; Sullivan, Mary E; Husband, Thomas P

    2015-01-01

    The New England cottontail (Sylvilagus transitionalis) is a high conservation priority in the Northeastern United States and has been listed as a candidate species under the Endangered Species Act. Loss of early successional habitat is the most common explanation for the decline of the species, which is considered to require habitat with dense low vegetation and limited overstory tree canopy. Federal and state wildlife agencies actively encourage landowners to create this habitat type by clearcutting blocks of forest. However, there are recent indications that the species also occupies sites with moderate overstory tree canopy cover. This is important because many landowners have negative views about clearcutting and are more willing to adopt silvicultural approaches that retain some overstory trees. Furthermore, it is possible that clearcuts with no overstory canopy cover may attract the eastern cottontail (S. floridanus), an introduced species with an expanding range. The objective of our study was to provide guidance for future efforts to create habitat that would be more favorable for New England cottontail than eastern cottontail in areas where the two species are sympatric. We analyzed canopy cover at 336 cottontail locations in five states using maximum entropy modelling and other statistical methods. We found that New England cottontail occupied sites with a mean overstory tree canopy cover of 58% (SE±1.36), and was less likely than eastern cottontail to occupy sites with lower overstory canopy cover and more likely to occupy sites with higher overstory canopy cover. Our findings suggest that silvicultural approaches that retain some overstory canopy cover may be appropriate for creating habitat for New England cottontail. We believe that our results will help inform critical management decisions for the conservation of New England cottontail, and that our methodology can be applied to analyses of habitat use of other critical wildlife species. PMID

  12. Kinetic energy of Throughfall in subtropical forests of SE China - effects of tree canopy structure, functional traits, and biodiversity.

    Directory of Open Access Journals (Sweden)

    Christian Geißler

    Full Text Available Throughfall kinetic energy (TKE plays an important role in soil erosion in forests. We studied TKE as a function of biodiversity, functional diversity as well as structural stand variables in a secondary subtropical broad-leaved forest in the Gutianshan National Nature Reserve (GNNR in south-east China, a biodiversity hotspot in the northern hemisphere with more than 250 woody species present. Using a mixed model approach we could identify significant effects of all these variables on TKE: TKE increased with rarefied tree species richness and decreased with increasing proportion of needle-leaved species and increasing leaf area index (LAI. Furthermore, for average rainfall amounts TKE was decreasing with tree canopy height whereas for high rainfall amounts this was not the case. The spatial pattern of throughfall was stable across several rain events. The temporal variation of TKE decreased with rainfall intensity and increased with tree diversity. Our results show that more diverse forest stands over the season have to cope with higher cumulative raindrop energy than less diverse stands. However, the kinetic energy (KE of one single raindrop is less predictable in diverse stands since the variability in KE is higher. This paper is the first to contribute to the understanding of the ecosystem function of soil erosion prevention in diverse subtropical forests.

  13. Prioritizing Preferable Locations for Increasing Urban Tree Canopy in New York City

    Directory of Open Access Journals (Sweden)

    Dexter H. Locke

    2010-01-01

    Full Text Available This paper presents a set of Geographic Information System (GIS methods for identifying and prioritizing tree planting sites in urban environments. It uses an analytical approach created by a University of Vermont service-learning class called “GIS Analysis of New York City's Ecology” that was designed to provide research support to the MillionTreesNYC tree planting campaign. These methods prioritize tree planting sites based on need (whether or not trees can help address specific issues in the community and suitability (biophysical constraints and planting partners’ existing programmatic goals. Criteria for suitability and need were based on input from three New York City tree-planting organizations. Customized spatial analysis tools and maps were created to show where each organization may contribute to increasing urban tree canopy (UTC while also achieving their own programmatic goals. These methods and associated custom tools can help decision-makers optimize urban forestry investments with respect to biophysical and socioeconomic outcomes in a clear and accountable manner. Additionally, the framework described here may be used in other cities, can track spatial characteristics of urban ecosystems over time, and may enable further tool development for collaborative decision-making in urban natural resource management.

  14. Attributes for MRB_E2RF1 Catchments by Major River Basins in the Conterminous United States: NLCD 2001 Tree Canopy

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — This tabular data set represents the mean percent tree canopy from the Canopy Layer of the National Land Cover Dataset 2001 (LaMotte and Wieczorek, 2010), compiled...

  15. Validation of Farmer Perceived Soil Fertility Improving Tree Species in Agropastoral Communities of Bushenyi District

    Directory of Open Access Journals (Sweden)

    Albert. K. Muzoora

    2011-01-01

    Full Text Available In sub-Saharan Africa, including Uganda, there is declining soil fertility and limited on-farm use of inorganic fertilizers due to poverty and limited subsidies for inorganic fertilizer use. Thus, integration of soil fertility improving tree species (SFITs in farming systems remains a plausible option to sustaining soil productivity. However, knowledge of the effects of many of the locally growing farmer perceived soil fertility enhancing tree species on to soil chemical and nutrient contents are thus still lacking, and this has constrained decisions on their adoption and scaling up. The objectives of this paper were to identify farmers' preferred soil fertility improving tree species in agropastoral communities of Kyeizooba subcounty Bushenyi district, and characterize their litter content and assess their effect on selected soil chemical properties. Semistructured questionnaires were administered to 333 randomly selected agropastoral farmers. Litter and soils under canopy soils were sampled from three different environments: Under canopy radius (A, canopy edge (B, open pasture land up to thrice the canopy radius (C. Results revealed Eucalyptus as the most common tree species on livestock farms, followed by Erythrina abyssinica. The highest litter content was recorded for Markhamia lutea (240 g/cm2 under its canopy followed by Croton macrostachyus (90 g/cm2, and 19 g/cm2 Erythrina abyssinica. Nitrogen was higher (P=.02 in Erythrina abyssinica litter, K and carbon in Croton macrostachyus litter (P=.03. These results give evidence that of soil improvers Erythrina abyssinica, Croton macrostachyus, and Markhamia lutea may positively affect soil fertility. Farmers' indigenous knowledge and or valuation of important tree species can be relied on, and thus, their indigenous knowledge need to be incorporated during identification of tree species for promotion in farming systems.

  16. Slope variation and population structure of tree species from different ecological groups in South Brazil

    OpenAIRE

    Edmilson Bianchini; Garcia, Cristina C.; José A. Pimenta; José M.D. Torezan

    2010-01-01

    Size structure and spatial arrangement of 13 abundant tree species were determined in a riparian forest fragment inParaná State, South Brazil (23"16'S and 51"01'W). The studied species were Aspidosperma polyneuron Müll. Arg., Astronium graveolens Jacq. and Gallesia integrifolia (Spreng) Harms (emergent species); Alseis floribunda Schott, Ruprechtia laxiflora Meisn. and Bougainvillea spectabilis Willd. (shade-intolerant canopy species); Machaerium paraguariense Hassl, Myroxylum peruiferum L. a...

  17. Species Tree Inference Using a Mixture Model.

    Science.gov (United States)

    Ullah, Ikram; Parviainen, Pekka; Lagergren, Jens

    2015-09-01

    Species tree reconstruction has been a subject of substantial research due to its central role across biology and medicine. A species tree is often reconstructed using a set of gene trees or by directly using sequence data. In either of these cases, one of the main confounding phenomena is the discordance between a species tree and a gene tree due to evolutionary events such as duplications and losses. Probabilistic methods can resolve the discordance by coestimating gene trees and the species tree but this approach poses a scalability problem for larger data sets. We present MixTreEM-DLRS: A two-phase approach for reconstructing a species tree in the presence of gene duplications and losses. In the first phase, MixTreEM, a novel structural expectation maximization algorithm based on a mixture model is used to reconstruct a set of candidate species trees, given sequence data for monocopy gene families from the genomes under study. In the second phase, PrIME-DLRS, a method based on the DLRS model (Åkerborg O, Sennblad B, Arvestad L, Lagergren J. 2009. Simultaneous Bayesian gene tree reconstruction and reconciliation analysis. Proc Natl Acad Sci U S A. 106(14):5714-5719), is used for selecting the best species tree. PrIME-DLRS can handle multicopy gene families since DLRS, apart from modeling sequence evolution, models gene duplication and loss using a gene evolution model (Arvestad L, Lagergren J, Sennblad B. 2009. The gene evolution model and computing its associated probabilities. J ACM. 56(2):1-44). We evaluate MixTreEM-DLRS using synthetic and biological data, and compare its performance with a recent genome-scale species tree reconstruction method PHYLDOG (Boussau B, Szöllősi GJ, Duret L, Gouy M, Tannier E, Daubin V. 2013. Genome-scale coestimation of species and gene trees. Genome Res. 23(2):323-330) as well as with a fast parsimony-based algorithm Duptree (Wehe A, Bansal MS, Burleigh JG, Eulenstein O. 2008. Duptree: a program for large-scale phylogenetic

  18. Spatial Patterns and Interspecific Associations of Three Canopy Species at Different Life Stages in a Subtropical Forest,China

    Institute of Scientific and Technical Information of China (English)

    Lin Li; Shi-Guang Wei; Zhong-Liang Huang; Wan-Hui Ye; Hong-Lin Cao

    2008-01-01

    Spatial patterns of species at different life stages are an important aspect for understanding causal mechanisms that facilitate species co-existence.Using Ripley's univariate L(t) and bivariate L12(t) functions,we analyzed the spatial patterns and interspecific associations of three canopy species at different life history stages in a 20-ha subtropical forest plot in Dinghushan Nature Reserve.Based on diameter at breast height (DBH),four life stages were distinguished.Castanopsis chinensis and Schima superba showed a unimodal DBH distribution.Engelhardtia roxburghiana showed a bimodal curve.L(t) function analysis showed significantly aggregated distributions of all three species at later life stages and random distribution at early life stages at some scales.From the analysis of L12(t) function,the results showed the positive association was a dominant pattern for most species pairs at most scales but the intensity of association decreases with the increase of life stages.Juveniles of the three species had no negative intra- and interspecific associations with the older life stages.Only premature trees were suppressed by overmature trees at some scales.Considering these results,we found three canopy-dominant species that lacked regeneration.There was no direct competition occurring between understorey individuals.Young trees can grow well under conspecific species with two other species.Longevity and lack of regeneration led to a large number of trees stored in mature and overmature stages,therefore,intra-and inter-competition can be strong at later life stages.

  19. Temperature profile in apricot tree canopies under the soil and climate conditions of the Romanian Black Sea Coast

    Science.gov (United States)

    Paltineanu, Cristian; Septar, Leinar; Chitu, Emil

    2016-03-01

    The paper describes the temperature profiles determined by thermal imagery in apricot tree canopies under the semi-arid conditions of the Black Sea Coast in a chernozem of Dobrogea Region, Romania. The study analyzes the thermal vertical profile of apricot orchards for three representative cultivars during summertime. Measurements were done when the soil water content (SWC) was at field capacity (FC) within the rooting depth, after intense sprinkler irrigation applications. Canopy temperature was measured during clear sky days at three heights for both sides of the apricot trees, sunlit (south), and shaded (north). For the SWC studied, i.e., FC, canopy height did not induce a significant difference between the temperature of apricot tree leaves (Tc) and the ambient air temperature (Ta) within the entire vertical tree profile, and temperature measurements by thermal imagery can therefore be taken at any height on the tree crown leaves. Differences between sunlit and shaded sides of the canopy were significant. Because of these differences for Tc-Ta among the apricot tree cultivars studied, lower base lines (LBLs) should be determined for each cultivar separately. The use of thermal imagery technique under the conditions of semi-arid coastal areas with low range of vapor pressure deficit could be useful in irrigation scheduling of apricot trees. The paper discusses the implications of the data obtained in the experiment under the conditions of the coastal area of the Black Sea, Romania, and neighboring countries with similar climate, such as Bulgaria and Turkey.

  20. Testing Accuracy of Long-Range Ultrasonic Sensors for Olive Tree Canopy Measurements

    Directory of Open Access Journals (Sweden)

    Juan Luis Gamarra-Diezma

    2015-01-01

    Full Text Available Ultrasonic sensors are often used to adjust spray volume by allowing the calculation of the crown volume of tree crops. The special conditions of the olive tree require the use of long-range sensors, which are less accurate and faster than the most commonly used sensors. The main objectives of the study were to determine the suitability of the sensor in terms of sound cone determination, angle errors, crosstalk errors and field measurements. Different laboratory tests were performed to check the suitability of a commercial long-range ultrasonic sensor, as were the experimental determination of the sound cone diameter at several distances for several target materials, the determination of the influence of the angle of incidence of the sound wave on the target and distance on the accuracy of measurements for several materials and the determination of the importance of the errors due to interference between sensors for different sensor spacings and distances for two different materials. Furthermore, sensor accuracy was tested under real field conditions. The results show that the studied sensor is appropriate for olive trees because the sound cone is narrower for an olive tree than for the other studied materials, the olive tree canopy does not have a large influence on the sensor accuracy with respect to distance and angle, the interference errors are insignificant for high sensor spacings and the sensor’s field distance measurements were deemed sufficiently accurate.

  1. The demography of range boundaries versus range cores in eastern US tree species.

    Science.gov (United States)

    Purves, Drew W

    2009-04-22

    Regional species-climate correlations are well documented, but little is known about the ecological processes responsible for generating these patterns. Using the data from over 690,000 individual trees I estimated five demographic rates--canopy growth, understorey growth, canopy lifespan, understorey lifespan and per capita reproduction--for 19 common eastern US tree species, within the core and the northern and southern boundaries, of the species range. Most species showed statistically significant boundary versus core differences in most rates at both boundary types. Differences in canopy and understorey growth were relatively small in magnitude but consistent among species, being lower at the northern (average -17%) and higher at the southern (average +12%) boundaries. Differences in lifespan were larger in magnitude but highly variable among species, except for a marked trend for reduced canopy lifespan at the northern boundary (average -49%). Differences in per capita reproduction were large and statistically significant for some species, but highly variable among species. The rate estimates were combined to calculate two performance indices: R(0) (a measure of lifetime fitness in the absence of competition) was consistently lower at the northern boundary (average -86%) whereas Z* (a measure of competitive ability in closed forest) showed no sign of a consistent boundary-core difference at either boundary.

  2. Effects of species selection and management on forest canopy albedo

    OpenAIRE

    Otto, Juliane; Berveiller, Daniel; Bréon, François-Marie; Delpierre, Nicolas; Geppert, Gernot; Granier, André; Gunia, Katja; Jans, Wilma; Knohl, Alexander; Kuusk, Andres; Longdoz, Bernard; Moors, Eddy; Mund, Martina; Pinty, Bernard; Rautiainen, Miina

    2013-01-01

    Forest management is considered to be one of the key instruments available to mitigate climate change as it can lead to increased sequestration of atmospheric carbon dioxide. However, the changes in canopy albedo may neutralise or offset the climate benefits of carbon sequestration. Although there is an emerging body of literature linking canopy albedo to management, understanding is still fragmented. We make use of a generally applicable approach: we combine a stand-level forest gap model wi...

  3. Reconciliation of Gene and Species Trees

    Directory of Open Access Journals (Sweden)

    L. Y. Rusin

    2014-01-01

    Full Text Available The first part of the paper briefly overviews the problem of gene and species trees reconciliation with the focus on defining and algorithmic construction of the evolutionary scenario. Basic ideas are discussed for the aspects of mapping definitions, costs of the mapping and evolutionary scenario, imposing time scales on a scenario, incorporating horizontal gene transfers, binarization and reconciliation of polytomous trees, and construction of species trees and scenarios. The review does not intend to cover the vast diversity of literature published on these subjects. Instead, the authors strived to overview the problem of the evolutionary scenario as a central concept in many areas of evolutionary research. The second part provides detailed mathematical proofs for the solutions of two problems: (i inferring a gene evolution along a species tree accounting for various types of evolutionary events and (ii trees reconciliation into a single species tree when only gene duplications and losses are allowed. All proposed algorithms have a cubic time complexity and are mathematically proved to find exact solutions. Solving algorithms for problem (ii can be naturally extended to incorporate horizontal transfers, other evolutionary events, and time scales on the species tree.

  4. Canopy arthropods community within and among oak species in central Mexico

    OpenAIRE

    Efraín TOVAR-SANCHEZ

    2009-01-01

    Quercus rugosa and Q.laurina are species that presents a wide geographical distribution range in temperate forests of Mexico. Oak canopies contain a considerable portion of arthropod diversity and the arthropods fauna fulfill a wide variety of ecological roles. We examined the effect of oak species and seasonal changes on some community structure parameters (diversity, composition, similarity, biomass, rare species, and density of arthropod fauna) of canopy arthropods. In total, 40 oak ca...

  5. Tree species and functional traits but not species richness affect interrill erosion processes in young subtropical forests

    Science.gov (United States)

    Seitz, S.; Goebes, P.; Song, Z.; Bruelheide, H.; Härdtle, W.; Kühn, P.; Li, Y.; Scholten, T.

    2016-01-01

    Soil erosion is seriously threatening ecosystem functioning in many parts of the world. In this context, it is assumed that tree species richness and functional diversity of tree communities can play a critical role in improving ecosystem services such as erosion control. An experiment with 170 micro-scale run-off plots was conducted to investigate the influence of tree species and tree species richness as well as functional traits on interrill erosion in a young forest ecosystem. An interrill erosion rate of 47.5 Mg ha-1 a-1 was calculated. This study provided evidence that different tree species affect interrill erosion differently, while tree species richness did not affect interrill erosion in young forest stands. Thus, different tree morphologies have to be considered, when assessing soil erosion under forest. High crown cover and leaf area index reduced interrill erosion in initial forest ecosystems, whereas rising tree height increased it. Even if a leaf litter cover was not present, the remaining soil surface cover by stones and biological soil crusts was the most important driver for soil erosion control. Furthermore, soil organic matter had a decreasing influence on interrill erosion. Long-term monitoring of soil erosion under closing tree canopies is necessary, and a wide range of functional tree traits should be considered in future research.

  6. Tree species composition affects the abundance of rowan (Sorbus aucuparia L.) in urban forests in Finland.

    Science.gov (United States)

    Hamberg, Leena; Lehvävirta, Susanna; Kotze, D Johan; Heikkinen, Juha

    2015-03-15

    Recent studies have shown a considerable increase in the abundance of rowan (Sorbus aucuparia) saplings in urban forests in Finland, yet the reasons for this increase are not well understood. Here we investigated whether canopy cover or tree species composition, i.e., the basal areas of different tree species in Norway spruce dominated urban forests, affects the abundances of rowan seedlings, saplings and trees. Altogether 24 urban forest patches were investigated. We sampled the number of rowan and other saplings, and calculated the basal areas of trees. We showed that rowan abundance was affected by tree species composition. The basal area of rowan trees (≥ 5 cm in diameter at breast height, dbh) decreased with increasing basal area of Norway spruce, while the cover of rowan seedlings increased with an increase in Norway spruce basal area. However, a decrease in the abundance of birch (Betula pendula) and an increase in the broad-leaved tree group (Acer platanoides, Alnus glutinosa, Alnus incana, Amelanchier spicata, Prunus padus, Quercus robur, Rhamnus frangula and Salix caprea) coincided with a decreasing number of rowans. Furthermore, rowan saplings were scarce in the vicinity of mature rowan trees. Although it seems that tree species composition has an effect on rowan, the relationship between rowan saplings and mature trees is complex, and therefore we conclude that regulating tree species composition is not an easy way to keep rowan thickets under control in urban forests in Finland.

  7. Fine-Scale Genetic Structure of Monilinia fructicola During Brown Rot Epidemics Within Individual Peach Tree Canopies.

    Science.gov (United States)

    Everhart, S E; Scherm, H

    2015-04-01

    The purpose of this study was to determine the fine-scale genetic structure of populations of the brown rot pathogen Monilinia fructicola within individual peach tree canopies to better understand within-tree plant pathogen diversity and to complement previous work on spatiotemporal development of brown rot disease at the canopy level. Across 3 years in a total of six trees, we monitored disease development, collected isolates from every M. fructicola symptom during the course of the season, and created high-resolution three-dimensional maps of all symptom and isolate locations within individual canopies using an electromagnetic digitizer. Each canopy population (65 to 173 isolates per tree) was characterized using a set of 13 microsatellite markers and analyzed for evidence of spatial genetic autocorrelation among isolates during the epidemic phase of the disease. Results showed high genetic diversity (average uh=0.529) and high genotypic diversity (average D=0.928) within canopies. The percentage of unique multilocus genotypes within trees was greater for blossom blight isolates (78.2%) than for fruit rot isolates (51.3%), indicating a greater contribution of clonal reproduction during the preharvest epidemic. For fruit rot isolates, between 54.2 and 81.7% of isolates were contained in one to four dominant clonal genotypes per tree having at least 10 members. All six fruit rot populations showed positive and significant spatial genetic autocorrelation for distance classes between 0.37 and 1.48 m. Despite high levels of within-tree pathogen diversity, the contribution of locally available inoculum combined with short-distance dispersal is likely the main factor generating clonal population foci and associated spatial genetic clustering within trees. PMID:25317843

  8. Large ontogenetic declines in intra-crown leaf area index in two temperate deciduous tree species.

    Science.gov (United States)

    Nock, C A; Caspersen, J P; Thomas, S C

    2008-03-01

    The widespread occurrence of age-related changes in leaf morphology and allocation suggests that the leaf area index of individual trees (intra-crown LAI) may decline late in ontogeny. We used direct, within-canopy measurements to quantify the LAI of canopy trees with exposed crowns of two temperate deciduous species. Intra-crown LAI declined from approximately 7 to 4 in Acer saccharum, and from approximately 9.5 to 6.5 in Betula alleghaniensis, as tree size increased (from 15 to 72 cm diameter at breast height [dbh]). For A. saccharum, age (which varied from 30 to 160 years) was a significantly better predictor of LAI decline than dbh. We also modeled the effect of ontogenetic declines in LAI on understory light availability and found that light transmission increases significantly as canopy trees grow and mature. Our results thus suggest that gradual declines in LAI with tree age may play an important and overlooked role in contributing to the heterogeneity of sub-canopy light regimes in mature forests. PMID:18459337

  9. Tree Species Specific Soil Moisture Patterns and Dynamics

    Science.gov (United States)

    Heidbuechel, I.; Dreibrodt, J.; Guntner, A.; Blume, T.

    2014-12-01

    Land use has a major influence on the hydrologic processes that take place in soils. Soil compaction on pastures for example leads to infiltration patterns that differ considerably from the ones observable in forests. It is not clear, however, how different forest stands influence soil infiltration and soil moisture distributions. Factors that that vary amongst different stands and potentially affect soil moisture processes in forests are, amongst others, canopy density, throughfall patterns, the intensity and frequency of stem flow, litter type, root distributions and rooting depth. To investigate how different tree species influence the way soils partition, store and conduct incoming precipitation we selected 15 locations under different tree stands within the TERENO observatory in north-east Germany. The forest stands under investigation were mature oak, young pine, mature pine, young beech and mature beech. At each location we installed 30 FDR soil moisture sensors grouped into five depth profiles (monitoring soil moisture from 10 cm to 200 cm) and 5 additional near surface sensors. The profile locations within each forest stand covered most of the anticipated variability by ranging from minimum to maximum distance to the trees including locations under more and less dense canopy. Supplementary to the FDR sensors, throughfall measurements, tensiometers and groundwater data were available to observe dynamics of tree water availability, water fluxes within the soils and percolation towards the groundwater. To identify patterns in space and time we referred to the statistical methods of wavelet analysis and temporal stability analysis. Finally, we tried to link the results from these analyses to specific hydrologic processes at the different locations.

  10. Do the rich get richer? Varying effects of tree species identity and diversity on the richness of understory taxa

    Science.gov (United States)

    Champagne, Juilette; Paine, C. E. Timothy; Schoolmaster, Donald; Stejskal, Robert; Volařík, Daniel; Šebesta, Jan; Trnka, Filip; Koutecký, Tomáš; Švarc, Petr; Svátek, Martin; Hector, Andy; Matula, Radim

    2016-01-01

    Understory herbs and soil invertebrates play key roles in soil formation and nutrient cycling in forests. Studies suggest that diversity in the canopy and in the understory are positively associated, but these studies often confound the effects of tree species diversity with those of tree species identity and abiotic conditions. We combined extensive field sampling with structural equation modeling to evaluate the simultaneous effects of tree diversity on the species diversity of understory herbs, beetles, and earthworms. The diversity of earthworms and saproxylic beetles was directly and positively associated with tree diversity, presumably because species of both these taxa specialize on certain species of trees. Tree identity also strongly affected diversity in the understory, especially for herbs, likely as a result of interspecific differences in canopy light transmittance or litter decomposition rates. Our results suggest that changes in forest management will disproportionately affect certain understory taxa. For instance, changes in canopy diversity will affect the diversity of earthworms and saproxylic beetles more than changes in tree species composition, whereas the converse would be expected for understory herbs and detritivorous beetles. We conclude that the effects of tree diversity on understory taxa can vary from positive to negative and may affect biogeochemical cycling in temperate forests. Thus, maintaining high diversity in temperate forests can promote the diversity of multiple taxa in the understory.

  11. A Versatile, Production-Oriented Approach to High-Resolution Tree-Canopy Mapping in Urban and Suburban Landscapes Using GEOBIA and Data Fusion

    OpenAIRE

    Jarlath O'Neil-Dunne; Sean MacFaden; Anna Royar

    2014-01-01

    The benefits of tree canopy in urban and suburban landscapes are increasingly well known: stormwater runoff control, air-pollution mitigation, temperature regulation, carbon storage, wildlife habitat, neighborhood cohesion, and other social indicators of quality of life. However, many urban areas lack high-resolution tree canopy maps that document baseline conditions or inform tree-planting programs, limiting effective study and management. This paper describes a GEOBIA approach to tree-canop...

  12. Vibration parameters assessment to develop a continuous lateral canopy shaker for mechanical harvesting of traditional olive trees

    Directory of Open Access Journals (Sweden)

    Rafael R. Sola-Guirado

    2016-06-01

    Full Text Available The fruit harvesting is a key factor involving both product quality and profitability. Particularly, mechanical harvesting of traditional oil olive orchards is hint by tree training system for manual harvesting, tree size and several and slanted trunks which makes difficult trunk shaker work. Therefore, canopy shaker technology could be a feasible alternative to develop an integral harvester able to work on irregular canopies. The aim of this research was to determine vibration parameters applied to the olive tree for efficient mechanical harvesting by canopy shaker measuring fruit removal efficiency and debris. In this work, a continuous lateral canopy shaker harvester has been developed and tested on large olive trees in order to analyse the operating harvester parameters and tree properties to improve mutual adaptation. Vibration amplitude and frequency, rod density and ground speed were assessed. Vibration amplitude and frequency beside ground speed were decisive factors on fruit removal efficiency. Increasing rod density has not influenced on removal efficiency although it increased significantly debris. Promising results has been reached with 77.3% of removal efficiency, applying a 28 s shaking duration, 0.17 m amplitude vibration and 12 rod drum. This result was obtained reporting 0.26 s of accumulative shaking time over 200 m/s2 resultant acceleration. The canopy shaker mechanism enabled more than 65% of detached fruits to fall vertically, facilitating catch fruit. In order to improve removal efficiency it is advisable to adapt trees, set high amplitude in the shaker mechanism, and enhance the contact time between rods and tree.

  13. High-resolution tree canopy mapping for New York City using LIDAR and object-based image analysis

    Science.gov (United States)

    MacFaden, Sean W.; O'Neil-Dunne, Jarlath P. M.; Royar, Anna R.; Lu, Jacqueline W. T.; Rundle, Andrew G.

    2012-01-01

    Urban tree canopy is widely believed to have myriad environmental, social, and human-health benefits, but a lack of precise canopy estimates has hindered quantification of these benefits in many municipalities. This problem was addressed for New York City using object-based image analysis (OBIA) to develop a comprehensive land-cover map, including tree canopy to the scale of individual trees. Mapping was performed using a rule-based expert system that relied primarily on high-resolution LIDAR, specifically its capacity for evaluating the height and texture of aboveground features. Multispectral imagery was also used, but shadowing and varying temporal conditions limited its utility. Contextual analysis was a key part of classification, distinguishing trees according to their physical and spectral properties as well as their relationships to adjacent, nonvegetated features. The automated product was extensively reviewed and edited via manual interpretation, and overall per-pixel accuracy of the final map was 96%. Although manual editing had only a marginal effect on accuracy despite requiring a majority of project effort, it maximized aesthetic quality and ensured the capture of small, isolated trees. Converting high-resolution LIDAR and imagery into usable information is a nontrivial exercise, requiring significant processing time and labor, but an expert system-based combination of OBIA and manual review was an effective method for fine-scale canopy mapping in a complex urban environment.

  14. Roles of Urban Tree Canopy and Buildings in Urban Heat Island Effects: Parameterization and Preliminary Results

    Science.gov (United States)

    Loughner, Christopher P.; Allen, Dale J.; Zhang, Da-Lin; Pickering, Kenneth E.; Dickerson, Russell R.; Landry, Laura

    2012-01-01

    Urban heat island (UHI) effects can strengthen heat waves and air pollution episodes. In this study, the dampening impact of urban trees on the UHI during an extreme heat wave in the Washington, D.C., and Baltimore, Maryland, metropolitan area is examined by incorporating trees, soil, and grass into the coupled Weather Research and Forecasting model and an urban canopy model (WRF-UCM). By parameterizing the effects of these natural surfaces alongside roadways and buildings, the modified WRF-UCM is used to investigate how urban trees, soil, and grass dampen the UHI. The modified model was run with 50% tree cover over urban roads and a 10% decrease in the width of urban streets to make space for soil and grass alongside the roads and buildings. Results show that, averaged over all urban areas, the added vegetation decreases surface air temperature in urban street canyons by 4.1 K and road-surface and building-wall temperatures by 15.4 and 8.9 K, respectively, as a result of tree shading and evapotranspiration. These temperature changes propagate downwind and alter the temperature gradient associated with the Chesapeake Bay breeze and, therefore, alter the strength of the bay breeze. The impact of building height on the UHI shows that decreasing commercial building heights by 8 m and residential building heights by 2.5 m results in up to 0.4-K higher daytime surface and near-surface air temperatures because of less building shading and up to 1.2-K lower nighttime temperatures because of less longwave radiative trapping in urban street canyons.

  15. Predicting spatial variations of tree species richness in tropical forests from high-resolution remote sensing.

    Science.gov (United States)

    Fricker, Geoffrey A; Wolf, Jeffrey A; Saatchi, Sassan S; Gillespie, Thomas W

    2015-10-01

    There is an increasing interest in identifying theories, empirical data sets, and remote-sensing metrics that can quantify tropical forest alpha diversity at a landscape scale. Quantifying patterns of tree species richness in the field is time consuming, especially in regions with over 100 tree species/ha. We examine species richness in a 50-ha plot in Barro Colorado Island in Panama and test if biophysical measurements of canopy reflectance from high-resolution satellite imagery and detailed vertical forest structure and topography from light detection and ranging (lidar) are associated with species richness across four tree size classes (>1, 1-10, >10, and >20 cm dbh) and three spatial scales (1, 0.25, and 0.04 ha). We use the 2010 tree inventory, including 204,757 individuals belonging to 301 species of freestanding woody plants or 166 ± 1.5 species/ha (mean ± SE), to compare with remote-sensing data. All remote-sensing metrics became less correlated with species richness as spatial resolution decreased from 1.0 ha to 0.04 ha and tree size increased from 1 cm to 20 cm dbh. When all stems with dbh > 1 cm in 1-ha plots were compared to remote-sensing metrics, standard deviation in canopy reflectance explained 13% of the variance in species richness. The standard deviations of canopy height and the topographic wetness index (TWI) derived from lidar were the best metrics to explain the spatial variance in species richness (15% and 24%, respectively). Using multiple regression models, we made predictions of species richness across Barro Colorado Island (BCI) at the 1-ha spatial scale for different tree size classes. We predicted variation in tree species richness among all plants (adjusted r² = 0.35) and trees with dbh > 10 cm (adjusted r² = 0.25). However, the best model results were for understory trees and shrubs (dbh 1-10 cm) (adjusted r² = 0.52) that comprise the majority of species richness in tropical forests. Our results indicate that high

  16. Predicting spatial variations of tree species richness in tropical forests from high-resolution remote sensing.

    Science.gov (United States)

    Fricker, Geoffrey A; Wolf, Jeffrey A; Saatchi, Sassan S; Gillespie, Thomas W

    2015-10-01

    There is an increasing interest in identifying theories, empirical data sets, and remote-sensing metrics that can quantify tropical forest alpha diversity at a landscape scale. Quantifying patterns of tree species richness in the field is time consuming, especially in regions with over 100 tree species/ha. We examine species richness in a 50-ha plot in Barro Colorado Island in Panama and test if biophysical measurements of canopy reflectance from high-resolution satellite imagery and detailed vertical forest structure and topography from light detection and ranging (lidar) are associated with species richness across four tree size classes (>1, 1-10, >10, and >20 cm dbh) and three spatial scales (1, 0.25, and 0.04 ha). We use the 2010 tree inventory, including 204,757 individuals belonging to 301 species of freestanding woody plants or 166 ± 1.5 species/ha (mean ± SE), to compare with remote-sensing data. All remote-sensing metrics became less correlated with species richness as spatial resolution decreased from 1.0 ha to 0.04 ha and tree size increased from 1 cm to 20 cm dbh. When all stems with dbh > 1 cm in 1-ha plots were compared to remote-sensing metrics, standard deviation in canopy reflectance explained 13% of the variance in species richness. The standard deviations of canopy height and the topographic wetness index (TWI) derived from lidar were the best metrics to explain the spatial variance in species richness (15% and 24%, respectively). Using multiple regression models, we made predictions of species richness across Barro Colorado Island (BCI) at the 1-ha spatial scale for different tree size classes. We predicted variation in tree species richness among all plants (adjusted r² = 0.35) and trees with dbh > 10 cm (adjusted r² = 0.25). However, the best model results were for understory trees and shrubs (dbh 1-10 cm) (adjusted r² = 0.52) that comprise the majority of species richness in tropical forests. Our results indicate that high

  17. Evolution of spectral behavior and chemical composition in the tree canopy of a dehesa ecosystem

    Directory of Open Access Journals (Sweden)

    R. González-Cascón

    2016-06-01

    Full Text Available In the context of the BIOSPEC and FLUXPEC projects (http://www.lineas.cchs.csic.es/fluxpec/, spectral and biophysical variables measurements at leaf level have been conducted in the tree canopy of a holm oak dehesa (Quercus ilex ecosystem during four vegetative periods. Measurements of bi-conical reflectance factor of intact leaf (ASD Fieldspec 3® spectroradiometer, specific leaf mass (SLM, leaf water content (LWC, nutrient (N, P, K, Ca, Mg, Mn, Fe, and Zn and chlorophyll concentration were performed. The spectral measurements have been related with the biophysical variables by stepwise and partial least squares regression analyses. These analyses allowed to identify the spectral bands and regions that best explain the evolution of the biophysical variables and to estimate the nutrient contents during the leaf maturation process. Statistically significant estimates of the majority of the variables studied were obtained. Wavelengths that had the highest contributions explaining the chemical composition of the forest canopy were located in spectral regions of the red edge, the green visible region, and the shortwave infrared.

  18. Tree and tree-like species of Mexico: gymnosperms, monocotyledons, and tree ferns

    OpenAIRE

    Martin Ricker; Hernández, Héctor M.

    2010-01-01

    Trees or tree-like plants are defined here broadly as perennial, self-supporting plants with an adult height of at least 5 m (without ascending leaves or inflorescences), and with 1 or several erect stems with a diameter of at least 10 cm. We present an updated list of all Mexican tree species under that definition in the Gymnospermae (86 species, 38% endemic to Mexico), Monocotyledonae (75 species, 55% endemic), and Pteridophyta (9 species, none endemic). The list contains a total of 170 spe...

  19. Model Simulation and Eigen-Analysis for Polarimetric Scattering from Tree Canopy in SAR Imagery

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    In this paper, a theoretical model of multi-level, non-spherical scatterers is develotped for fully polarimetric scattering from tree canopy in SAR imaging at C band. The amplitude functions of non-spherical particles with randomly spatial orientation are derived by the generalized Rayleigh Gans (GRG) approximation. The non-diagonal extinction matrix and the Mueller matrix solution are constructed. Numerical solutions of polarimetric scattering of four Stokes parametersfrom random, non-spherical scatterers are obtained. To physically identify polarimetric scattering of the Mueller matrix solution, the coherency matrix and its eigen-analysis are discussed. Functional dependence of the coherency matrix and entropy upon various parameters are obtained. As an application, the analysis of AirSAR images at P, L, C bands is discussed.

  20. Pushing the pace of tree species migration.

    Directory of Open Access Journals (Sweden)

    Eli D Lazarus

    Full Text Available Plants and animals have responded to past climate changes by migrating with habitable environments, sometimes shifting the boundaries of their geographic ranges by tens of kilometers per year or more. Species migrating in response to present climate conditions, however, must contend with landscapes fragmented by anthropogenic disturbance. We consider this problem in the context of wind-dispersed tree species. Mechanisms of long-distance seed dispersal make these species capable of rapid migration rates. Models of species-front migration suggest that even tree species with the capacity for long-distance dispersal will be unable to keep pace with future spatial changes in temperature gradients, exclusive of habitat fragmentation effects. Here we present a numerical model that captures the salient dynamics of migration by long-distance dispersal for a generic tree species. We then use the model to explore the possible effects of assisted colonization within a fragmented landscape under a simulated tree-planting scheme. Our results suggest that an assisted-colonization program could accelerate species-front migration rates enough to match the speed of climate change, but such a program would involve an environmental-sustainability intervention at a massive scale.

  1. [Hyperspectral Estimation of Apple Tree Canopy LAI Based on SVM and RF Regression].

    Science.gov (United States)

    Han, Zhao-ying; Zhu, Xi-cun; Fang, Xian-yi; Wang, Zhuo-yuan; Wang, Ling; Zhao, Geng-Xing; Jiang, Yuan-mao

    2016-03-01

    Leaf area index (LAI) is the dynamic index of crop population size. Hyperspectral technology can be used to estimate apple canopy LAI rapidly and nondestructively. It can be provide a reference for monitoring the tree growing and yield estimation. The Red Fuji apple trees of full bearing fruit are the researching objects. Ninety apple trees canopies spectral reflectance and LAI values were measured by the ASD Fieldspec3 spectrometer and LAI-2200 in thirty orchards in constant two years in Qixia research area of Shandong Province. The optimal vegetation indices were selected by the method of correlation analysis of the original spectral reflectance and vegetation indices. The models of predicting the LAI were built with the multivariate regression analysis method of support vector machine (SVM) and random forest (RF). The new vegetation indices, GNDVI527, ND-VI676, RVI682, FD-NVI656 and GRVI517 and the previous two main vegetation indices, NDVI670 and NDVI705, are in accordance with LAI. In the RF regression model, the calibration set decision coefficient C-R2 of 0.920 and validation set decision coefficient V-R2 of 0.889 are higher than the SVM regression model by 0.045 and 0.033 respectively. The root mean square error of calibration set C-RMSE of 0.249, the root mean square error validation set V-RMSE of 0.236 are lower than that of the SVM regression model by 0.054 and 0.058 respectively. Relative analysis of calibrating error C-RPD and relative analysis of validation set V-RPD reached 3.363 and 2.520, 0.598 and 0.262, respectively, which were higher than the SVM regression model. The measured and predicted the scatterplot trend line slope of the calibration set and validation set C-S and V-S are close to 1. The estimation result of RF regression model is better than that of the SVM. RF regression model can be used to estimate the LAI of red Fuji apple trees in full fruit period. PMID:27400527

  2. [Hyperspectral Estimation of Apple Tree Canopy LAI Based on SVM and RF Regression].

    Science.gov (United States)

    Han, Zhao-ying; Zhu, Xi-cun; Fang, Xian-yi; Wang, Zhuo-yuan; Wang, Ling; Zhao, Geng-Xing; Jiang, Yuan-mao

    2016-03-01

    Leaf area index (LAI) is the dynamic index of crop population size. Hyperspectral technology can be used to estimate apple canopy LAI rapidly and nondestructively. It can be provide a reference for monitoring the tree growing and yield estimation. The Red Fuji apple trees of full bearing fruit are the researching objects. Ninety apple trees canopies spectral reflectance and LAI values were measured by the ASD Fieldspec3 spectrometer and LAI-2200 in thirty orchards in constant two years in Qixia research area of Shandong Province. The optimal vegetation indices were selected by the method of correlation analysis of the original spectral reflectance and vegetation indices. The models of predicting the LAI were built with the multivariate regression analysis method of support vector machine (SVM) and random forest (RF). The new vegetation indices, GNDVI527, ND-VI676, RVI682, FD-NVI656 and GRVI517 and the previous two main vegetation indices, NDVI670 and NDVI705, are in accordance with LAI. In the RF regression model, the calibration set decision coefficient C-R2 of 0.920 and validation set decision coefficient V-R2 of 0.889 are higher than the SVM regression model by 0.045 and 0.033 respectively. The root mean square error of calibration set C-RMSE of 0.249, the root mean square error validation set V-RMSE of 0.236 are lower than that of the SVM regression model by 0.054 and 0.058 respectively. Relative analysis of calibrating error C-RPD and relative analysis of validation set V-RPD reached 3.363 and 2.520, 0.598 and 0.262, respectively, which were higher than the SVM regression model. The measured and predicted the scatterplot trend line slope of the calibration set and validation set C-S and V-S are close to 1. The estimation result of RF regression model is better than that of the SVM. RF regression model can be used to estimate the LAI of red Fuji apple trees in full fruit period.

  3. Impact of tree planting configuration on canopy interception and soil hydrological properties: Implications for flood mitigation in silvopastoral systems

    Science.gov (United States)

    Lunka, Peter; Patil, Sopan

    2015-04-01

    Compaction of upper soil layers by intensive sheep grazing has been connected with increased local flood risk in silvopastoral systems. A 12 week field study was conducted at the Henfaes Research Station near Bangor, Wales to compare two silvopastoral configurations, trees planted in fenced off clumps and trees planted evenly spaced, in terms of canopy throughfall, soil water infiltration and soil bulk density. The study's aim was to characterize the potential of these tree planting configurations to reduce local flood risk. The study site (Henfaes) was established in 1992 on 14 ha of agricultural land and is part of the Silvopastoral National Network Experiment sites that have been set up across the UK to examine the potential of silvopasture and agroforestry on UK farms. Automated throughfall gauges were installed in each silvopastoral treatment along with a similarly designed control gauge located in the grazed control pasture. Soil water infiltration and bulk density were measured 20 times in a stratified random design for each treatment and the control. Soil infiltration capacity in the clumped configuration was significantly higher than in the even spaced configuration and control pasture. The clumped configuration had mean infiltration capacity 504% greater than the control pasture and 454% greater than the even spaced configuration. Canopy interception was higher in the clumped trees than in the evenly spaced trees. Average canopy interception was 34% in the clumped treatment and 28% in the evenly spaced treatment. Soil bulk density was lower in the clumped configuration than in the control pasture and evenly spaced configuration. Results suggest that in silvopastoral systems the clumped tree configuration is more likely to reduce local flood risk than the evenly spaced tree configuration due to enhanced infiltration and increased canopy interception.

  4. [Time lag characteristics of stem sap flow of common tree species during their growth season in Beijing downtown].

    Science.gov (United States)

    Wang, Hua; Ouyang, Zhi-yun; Zheng, Hua; Wang, Xiao-ke; Ni, Yong-ming; Ren, Yu-fen

    2009-09-01

    From April to September in 2008, the stem sap flow velocity (Js) of several common tree species (Ginkgo biloba, Aesculus chinensis, Magnolia denudata, Robinia pseudoacacia, Pinus tabulaeformis and Cedrus deodara) in Beijing was measured by thermal dissipation method. Crosscorrelation analysis was used to estimate the time lag between the stem sap flow and the driving factors of canopy transpiration among the tree species. The Js of the six tree species was significantly correlated with the total radiation (Rs) and vapor pressure deficit (D), and the Js was lagged behind Rs but ahead of D. The maximum correlation coefficient of Js with Rs (0.74-0.93) was often higher than that of Js with D (0.57-0.79), indicating that the diurnal Js was more dependent on Rs than on D. The sampled tree species except P. tabulaeformis had a shorter time lag of Js with Rs (10-70 min) than with D (47-130 min), and there existed significant differences among R. pseudoacacia, P. tabulaeformis, and C. deodara. The time lag between the Js and the driving factors of canopy transpiration was mainly correlated with the tree features (DBH, tree height, canopy area, and sapwood area) and the nocturnal water recharge, regardless of tree species.

  5. [Time lag characteristics of stem sap flow of common tree species during their growth season in Beijing downtown].

    Science.gov (United States)

    Wang, Hua; Ouyang, Zhi-yun; Zheng, Hua; Wang, Xiao-ke; Ni, Yong-ming; Ren, Yu-fen

    2009-09-01

    From April to September in 2008, the stem sap flow velocity (Js) of several common tree species (Ginkgo biloba, Aesculus chinensis, Magnolia denudata, Robinia pseudoacacia, Pinus tabulaeformis and Cedrus deodara) in Beijing was measured by thermal dissipation method. Crosscorrelation analysis was used to estimate the time lag between the stem sap flow and the driving factors of canopy transpiration among the tree species. The Js of the six tree species was significantly correlated with the total radiation (Rs) and vapor pressure deficit (D), and the Js was lagged behind Rs but ahead of D. The maximum correlation coefficient of Js with Rs (0.74-0.93) was often higher than that of Js with D (0.57-0.79), indicating that the diurnal Js was more dependent on Rs than on D. The sampled tree species except P. tabulaeformis had a shorter time lag of Js with Rs (10-70 min) than with D (47-130 min), and there existed significant differences among R. pseudoacacia, P. tabulaeformis, and C. deodara. The time lag between the Js and the driving factors of canopy transpiration was mainly correlated with the tree features (DBH, tree height, canopy area, and sapwood area) and the nocturnal water recharge, regardless of tree species. PMID:20030130

  6. An Analysis of Overstory Tree Canopy Cover in Sites Occupied by Native and Introduced Cottontails in the Northeastern United States with Recommendations for Habitat Management for New England Cottontail

    OpenAIRE

    Bill Buffum; Thomas J McGreevy; Gottfried, Amy E.; Sullivan, Mary E.; Husband, Thomas P.

    2015-01-01

    The New England cottontail (Sylvilagus transitionalis) is a high conservation priority in the Northeastern United States and has been listed as a candidate species under the Endangered Species Act. Loss of early successional habitat is the most common explanation for the decline of the species, which is considered to require habitat with dense low vegetation and limited overstory tree canopy. Federal and state wildlife agencies actively encourage landowners to create this habitat type by clea...

  7. Region effects influence local tree species diversity.

    Science.gov (United States)

    Ricklefs, Robert E; He, Fangliang

    2016-01-19

    Global patterns of biodiversity reflect both regional and local processes, but the relative importance of local ecological limits to species coexistence, as influenced by the physical environment, in contrast to regional processes including species production, dispersal, and extinction, is poorly understood. Failure to distinguish regional influences from local effects has been due, in part, to sampling limitations at small scales, environmental heterogeneity within local or regional samples, and incomplete geographic sampling of species. Here, we use a global dataset comprising 47 forest plots to demonstrate significant region effects on diversity, beyond the influence of local climate, which together explain more than 92% of the global variation in local forest tree species richness. Significant region effects imply that large-scale processes shaping the regional diversity of forest trees exert influence down to the local scale, where they interact with local processes to determine the number of coexisting species.

  8. Canopy recovery of pedunculate oak, Turkey oak and beech trees after severe defoliation by gypsy moth (Lymantria dispar): Case study from Western Hungary

    OpenAIRE

    Csóka György; Pödör Zoltán; Nagy Gyula; Hirka Anikó

    2015-01-01

    We investigated the canopy recovery of 3 tree species (pedunculate oak, Turkey oak, European beech) at two locations in the Veszprém county (Western Hungary) after severe defoliation by gypsy moth caterpillars in the spring of 2005. The Turkey oak has evidently the best recovery potential, and it almost completely replaced the lost foliage in 4 months. The pedunculate oak and beech needed 2 years to reach the same level of recovery. The pedunculate oak suffered from a heavy infection of Micro...

  9. A tree species inventory in a one-hectare plot at the Batang Gadis National Park, North Sumatra, Indonesia

    Directory of Open Access Journals (Sweden)

    Kuswata Kartawinata

    2003-12-01

    Full Text Available KARTAWINATA, KUSWATA; SAMSOEDIN, ISMAYADI; HERIYANTO, M. AND AFRIASTINI, J. J. 2004. A tree species inventory in a one-hectare plot at the Batang Gadis National Park, North Sumatra, Indonesia. Reinwardtia 12 (2: 145 – 157. The results of the inventory of trees with DBH ≥ 10 cm shows that 184 species in 41 families, represented by 583 individuals with the total basal areas of 40.56 m² occurred in the one-hectare plot sampled. Together with the saplings and shrubs the number of species was 240 belonging to 47 families. The forest is richer in tree species than other lowland forests in North Sumatra, but poorer than those in Borneo and the Malay Peninsula. Dipterocarps constituted 18.42 % of total species with basal area of 18.99 m² or 46.82 % of the total basal area in the plot. The most prominent species was Shorea gibbosa. Hopea nigra, reported to be rare in Bangka and Belitung, occurred here as one of the ten leading species. The species-area curve shows that a considerable number of additional species was encountered more or less steadily up to one hectare and there was no indication of levelling off. A simulated profile diagram shows the forest may be stratified into five layers: (1 emergent layer, (2 upper canopy, (3 middle canopy, (4 lower canopy and (5 ground canopy. Dipterocarps were leading species in the emergent layer, upper canopy and middle canopy. Only 82 species were regenerating as represented by their presence in the sapling stage ranging from 5 to 50 plants/hectare. Macaranga lowii King ex Hook. f. dominated the section which seemed to be previously occupied by gaps.

  10. Statistical mapping of tree species over Europe

    NARCIS (Netherlands)

    Brus, D.J.; Hengeveld, G.M.; Walvoort, D.J.J.; Goedhart, P.W.; Heidema, A.H.; Nabuurs, G.J.; Gunia, K.

    2012-01-01

    In order to map the spatial distribution of twenty tree species groups over Europe at 1 km × 1 km resolution, the ICP-Forest Level-I plot data were extended with the National Forest Inventory (NFI) plot data of eighteen countries. The NFI grids have a much smaller spacing than the ICP grid. In areas

  11. Terrestrial arthropods from tree canopies in the Pantanal of Mato Grosso, Brazil

    Directory of Open Access Journals (Sweden)

    Marinêz Isaac Marques

    2006-06-01

    Full Text Available Terrestrial arthropods from tree canopies in the Pantanal of Mato Grosso, Brazil. This study represents a contribution to the knowledge of the diversity of arthropods associated to the canopy of Vochysia divergens Pohl (Vochysiaceae. Three trees individuals were sampled during two seasonal periods in this region: a by spraying one tree canopy during high water (February; b by fogging two tree canopies during low water (September/October. The 15,744 arthropods (183.2±38.9 individuals/m² obtained from all three trees (86 m² represented 20 taxonomic orders, 87.1% were Insecta, and 12.9% Arachnida. The dominant groups were Hymenoptera (48.5%; 88.9 individuals/m², mostly Formicidae (44.5%; 81.4 individuals/m², followed by Coleoptera (14.0%; 25.5 individuals/m² and Araneae (10.2%; 19.5 individuals/m², together representing 62.5% of the total catch. Fourteen (70% of all orders occurred on three trees. Dermaptera, Isoptera, Neuroptera, Odonata, Plecoptera and Trichoptera were collected from only one tree. Of the total, 2,197 adult Coleoptera collected (25.5±11.3 individuals/m², 99% were assigned to 32 families and 256 morphospecies. Nitidulidae (17.9% of the total catch; 4.6 individuals/m², Anobiidae (16.7%; 4.3 individuals/m², Curculionidae (13.2%; 3.4 individuals/m² and Meloidae (11.4%; 2.9 individuals/m² dominated. The communitiy of adult Coleoptera on V. divergens indicated a dominance of herbivores (37.8% of the total catch, 127 spp. and predators (35.2%, 82 spp., followed by saprophages (16.2%, 32 spp. and fungivores (10.8%, 15 spp.. The influence of the flood pulse on the community of arboreal arthropods in V. divergens is indicated by the seasonal variation in evaluated groups, causing changes in their structure and composition.Artrópodes terrestres associados a copas de árvores no Pantanal de Mato Grosso, Brasil. Este estudo representa uma contribuição ao conhecimento da diversidade de artrópodes associados à copa de Vochysia

  12. Mapping Urban Tree Canopy Coverage and Structure using Data Fusion of High Resolution Satellite Imagery and Aerial Lidar

    Science.gov (United States)

    Elmes, A.; Rogan, J.; Williams, C. A.; Martin, D. G.; Ratick, S.; Nowak, D.

    2015-12-01

    Urban tree canopy (UTC) coverage is a critical component of sustainable urban areas. Trees provide a number of important ecosystem services, including air pollution mitigation, water runoff control, and aesthetic and cultural values. Critically, urban trees also act to mitigate the urban heat island (UHI) effect by shading impervious surfaces and via evaporative cooling. The cooling effect of urban trees can be seen locally, with individual trees reducing home HVAC costs, and at a citywide scale, reducing the extent and magnitude of an urban areas UHI. In order to accurately model the ecosystem services of a given urban forest, it is essential to map in detail the condition and composition of these trees at a fine scale, capturing individual tree crowns and their vertical structure. This paper presents methods for delineating UTC and measuring canopy structure at fine spatial resolution (HVAC benefits from UTC for individual homes, and for assessing the ecosystem services for entire urban areas. Such maps have previously been made using a variety of methods, typically relying on high resolution aerial or satellite imagery. This paper seeks to contribute to this growing body of methods, relying on a data fusion method to combine the information contained in high resolution WorldView-3 satellite imagery and aerial lidar data using an object-based image classification approach. The study area, Worcester, MA, has recently undergone a large-scale tree removal and reforestation program, following a pest eradication effort. Therefore, the urban canopy in this location provides a wide mix of tree age class and functional type, ideal for illustrating the effectiveness of the proposed methods. Early results show that the object-based classifier is indeed capable of identifying individual tree crowns, while continued research will focus on extracting crown structural characteristics using lidar-derived metrics. Ultimately, the resulting fine resolution UTC map will be

  13. Mapping Urban Tree Canopy Coverage and Structure using Data Fusion of High Resolution Satellite Imagery and Aerial Lidar

    Science.gov (United States)

    Elmes, A.; Rogan, J.; Williams, C. A.; Martin, D. G.; Ratick, S.; Nowak, D.

    2015-12-01

    Urban tree canopy (UTC) coverage is a critical component of sustainable urban areas. Trees provide a number of important ecosystem services, including air pollution mitigation, water runoff control, and aesthetic and cultural values. Critically, urban trees also act to mitigate the urban heat island (UHI) effect by shading impervious surfaces and via evaporative cooling. The cooling effect of urban trees can be seen locally, with individual trees reducing home HVAC costs, and at a citywide scale, reducing the extent and magnitude of an urban areas UHI. In order to accurately model the ecosystem services of a given urban forest, it is essential to map in detail the condition and composition of these trees at a fine scale, capturing individual tree crowns and their vertical structure. This paper presents methods for delineating UTC and measuring canopy structure at fine spatial resolution (<1m). These metrics are essential for modeling the HVAC benefits from UTC for individual homes, and for assessing the ecosystem services for entire urban areas. Such maps have previously been made using a variety of methods, typically relying on high resolution aerial or satellite imagery. This paper seeks to contribute to this growing body of methods, relying on a data fusion method to combine the information contained in high resolution WorldView-3 satellite imagery and aerial lidar data using an object-based image classification approach. The study area, Worcester, MA, has recently undergone a large-scale tree removal and reforestation program, following a pest eradication effort. Therefore, the urban canopy in this location provides a wide mix of tree age class and functional type, ideal for illustrating the effectiveness of the proposed methods. Early results show that the object-based classifier is indeed capable of identifying individual tree crowns, while continued research will focus on extracting crown structural characteristics using lidar-derived metrics. Ultimately

  14. Direct vs. Microclimate-Driven Effects of Tree Species Diversity on Litter Decomposition in Young Subtropical Forest Stands

    Science.gov (United States)

    Seidelmann, Katrin N.; Scherer-Lorenzen, Michael; Niklaus, Pascal A.

    2016-01-01

    Effects of tree species diversity on decomposition can operate via a multitude of mechanism, including alterations of microclimate by the forest canopy. Studying such effects in natural settings is complicated by the fact that topography also affects microclimate and thus decomposition, so that effects of diversity are more difficult to isolate. Here, we quantified decomposition rates of standard litter in young subtropical forest stands, separating effects of canopy tree species richness and topography, and quantifying their direct and micro-climate-mediated components. Our litterbag study was carried out at two experimental sites of a biodiversity-ecosystem functioning field experiment in south-east China (BEF-China). The field sites display strong topographical heterogeneity and were planted with tree communities ranging from monocultures to mixtures of 24 native subtropical tree species. Litter bags filled with senescent leaves of three native tree species were placed from Nov. 2011 to Oct. 2012 on 134 plots along the tree species diversity gradient. Topographic features were measured for all and microclimate in a subset of plots. Stand species richness, topography and microclimate explained important fractions of the variations in litter decomposition rates, with diversity and topographic effects in part mediated by microclimatic changes. Tree stands were 2–3 years old, but nevertheless tree species diversity explained more variation (54.3%) in decomposition than topography (7.7%). Tree species richness slowed litter decomposition, an effect that slightly depended on litter species identity. A large part of the variance in decomposition was explained by tree species composition, with the presence of three tree species playing a significant role. Microclimate explained 31.4% of the variance in decomposition, and was related to lower soil moisture. Within this microclimate effect, species diversity (without composition) explained 8.9% and topography 34.4% of

  15. Tree species effects on topsoil properties in an old tropical plantation

    Science.gov (United States)

    Bauters, Marijn; Boeckx, Pascal; Ampoorter, Evy; Verbeeck, Hans; Döetterl, Sebastian; Baert, Geert; Verheyen, Kris

    2016-04-01

    Forest biogeochemistry is strongly linked to the functional strategies of the tree community and the topsoil. Research has long documented that tree species affect soil properties in forests. Our current understanding on this interaction is mainly based on common garden experiments in temperate forest and needs to be extended to other ecosystems if we want to understand this interaction in natural forests worldwide. Using a 77-year-old tropical experimental plantation from central Africa, we examined the relationship between canopy and litter chemical traits and topsoil properties. By the current diversity in this site, the unique setup allowed us to extend the current knowledge from temperate and simplified systems to near-natural tropical forests, and thus bridge the gap between planted monocultures in common gardens, and correlative studies in natural systems. We linked the species-specific leaf and litter chemical traits to the topsoil cation composition, acidity, pH and soil organic matter. We found that average canopy trait values were a better predictor for the topsoil than the litter chemistry. Canopy base cation content positively affected topsoil pH and negatively affected acidity. These, in turn strongly determined the soil organic carbon contents of the topsoil, which ranged a tree-fold in the experiment.

  16. Designing mixed species tree plantations for the tropics: balancing ecological attributes of species with landholder preferences in the Philippines.

    Science.gov (United States)

    Nguyen, Huong; Lamb, David; Herbohn, John; Firn, Jennifer

    2014-01-01

    A mixed species reforestation program known as the Rainforestation Farming system was undertaken in the Philippines to develop forms of farm forestry more suitable for smallholders than the simple monocultural plantations commonly used then. In this study, we describe the subsequent changes in stand structure and floristic composition of these plantations in order to learn from the experience and develop improved prescriptions for reforestation systems likely to be attractive to smallholders. We investigated stands aged from 6 to 11 years old on three successive occasions over a 6 year period. We found the number of species originally present in the plots as trees >5 cm dbh decreased from an initial total of 76 species to 65 species at the end of study period. But, at the same time, some new species reached the size class threshold and were recruited into the canopy layer. There was a substantial decline in tree density from an estimated stocking of about 5000 trees per ha at the time of planting to 1380 trees per ha at the time of the first measurement; the density declined by a further 4.9% per year. Changes in composition and stand structure were indicated by a marked shift in the Importance Value Index of species. Over six years, shade-intolerant species became less important and the native shade-tolerant species (often Dipterocarps) increased in importance. Based on how the Rainforestation Farming plantations developed in these early years, we suggest that mixed-species plantations elsewhere in the humid tropics should be around 1000 trees per ha or less, that the proportion of fast growing (and hence early maturing) trees should be about 30-40% of this initial density and that any fruit tree component should only be planted on the plantation margin where more light and space are available for crowns to develop. PMID:24751720

  17. Detecting forest canopy layering: applying lidar remote sensing to further understand the role of vertical structure in species habitat preference

    Science.gov (United States)

    Whitehurst, A. S.; Dubayah, R.; Swatantran, A.

    2011-12-01

    Full waveform lidar reflects off all forest canopy elements, showing not only height, but also the structure within the canopy from the top to the forest floor, making it an ideal remote sensing technology for research in forest ecosystem dynamics. Vertical stratification or canopy layering has long been noted as an essential element in the forest ecosystem and of importance for species habitat. This project explores the utility of lidar for characterizing forest canopy layering and applying canopy layering information to better understand species habitat preference. Canopy layering will be mapped across the landscape using full-waveform lidar remote sensing data from the NASA Goddard Space Flight Center Laser Vegetation Imaging Sensor (LVIS). Two methods for quantifying layering have been developed from LVIS data collected during the summer of 2009 for Hubbard Brook Experimental Forest, New Hampshire. The two layering datasets (one categorical, one continuous) describe how vertical stratification varies across the forest with canopy height and elevation. The relationships between of canopy layering and avian species habitat preference will also be assessed for bird species within Hubbard Brook Experimental forest. These results will provide ecologically meaningful information and a relevant method for quantifying canopy layering at the landscape scale, which will aid in a better understanding of forest ecosystem dynamics for forest management and species habitat research.

  18. A tree species inventory over Europe

    Science.gov (United States)

    Ambelas Skjøth, C.; Geels, C.; Hvidberg, M.; Hertel, O.; Brandt, J.; Frohn, L. M.; Hansen, K. M.; Hedegaard, G. B.; Christensen, J. H.; Moseholm, L.

    2009-04-01

    Atmospheric transport models are used in studies of atmospheric chemistry as well as aerobiology. Atmospheric transport models in general needs accurate emissions inventories, which includes biogenic emissions such as Volatile Organic Compounds (VOCs) and pollen. Trees are important VOC and pollen sources and a needed requirement is specie distribution which takes into account important species such as Betula and Alnus. We present here a detailed tree species inventory covering Europe, parts of Africa and parts of Asia. Forest inventories have been obtained for each European country, parts of Asia and parts of Africa. The national inventories vary with respect to number of species as well as the number of sub-regions each nation is divided into. The inventories are therefore harmonised within a GIS system and afterwards gridded to the model grid defined by the EMEP model: 50 km x 50 km. The inventory is designed to be used with existing land-use data, which separates forest cover into broad leaved, mixed and conifer forests. This will be exemplified by using two different remote sensing products with different grid resolution such as GLC2000 and CLC2000 in selected areas. The final inventory includes 16 conifer species and 23 broadleaved species that are important for biogenic VOCs or pollen emission calculations. For example: Oak (Quercus), poplar (Populus), pines (Pinus), spruce (Picea), birch (Betula) and alder (Alnus). 774 regions with forest inventories are included, mainly on sub-national level. The coverage of each specie ranges from national to European scale, where the latter includes VOC and allergy relevant species such as Quercus, Alnus and Betula. The inventory is gridded to the model grid defined by the EMEP model, which is also the basis for many emissions inventories throughout Europe. The inventory is therefore prepared for easy implementation into atmospheric transport models by providing an extension to already applied land use data such as the

  19. Influence of tree canopy on N₂ fixation by pasture legumes and soil rhizobial abundance in Mediterranean oak woodlands.

    Science.gov (United States)

    Carranca, C; Castro, I V; Figueiredo, N; Redondo, R; Rodrigues, A R F; Saraiva, I; Maricato, R; Madeira, M A V

    2015-02-15

    Symbiotic N2 fixation is of primordial significance in sustainable agro-forestry management as it allows reducing the use of mineral N in the production of mixed stands and by protecting the soils from degradation. Thereby, on a 2-year basis, N2 fixation was evaluated in four oak woodlands under Mediterranean conditions using a split-plot design and three replicates. (15)N technique was used for determination of N2 fixation rate. Variations in environmental conditions (temperature, rainfall, radiation) by the cork tree canopy as well as the age of stands and pasture management can cause great differences in vegetation growth, legume N2 fixation, and soil rhizobial abundance. In the present study, non-legumes dominated the swards, in particular beneath the tree canopy, and legumes represented only 42% of total herbage. A 2-fold biomass reduction was observed in the oldest sown pasture in relation to the medium-age sward (6 t DW ha(-1)yr(-1)). Overall, competition of pasture growth for light was negligible, but soil rhizobial abundance and symbiotic N2 fixation capacity were highly favored by this environmental factor in the spring and outside the influence of tree canopy. Nitrogen derived from the atmosphere was moderate to high (54-72%) in unsown and sown swards. Inputs of fixed N2 increased from winter to spring due to more favorable climatic conditions (temperature and light intensity) for both rhizobia and vegetation growths. Assuming a constant fixation rate at each seasonal period, N2 fixation capacity increased from about 0.10 kg N ha(-1) per day in the autumn-winter period to 0.15 kg N ha(-1) per day in spring. Belowground plant material contributed to 11% of accumulated N in pasture legumes and was not affected by canopy. Size of soil fixing bacteria contributed little to explain pasture legumes N.

  20. Estimation of dry deposition fluxes of major inorganic species by canopy throughfall approach

    Institute of Scientific and Technical Information of China (English)

    JIN Lei; SHAO Min; ZENG Limin; ZHAO Dawei; TANG Dagang

    2006-01-01

    Dry deposition in China has not yet been intensively studied even though it constitutes an important pathway for acid deposition. The total deposition was monitored at Tieshanping catchment, a regional remote site in Chongqing City. The dry deposition loads of sulphur, calcium and nitrogen are estimated by using a canopy throughfall approach. The results indicate that the annual dry deposition loads of sulphur and calcium at Tieshanping site are much higher than those measured in forestry areas in other countries, while the dry deposition flux of nitrogen is at a comparable level. The dry deposition loads of sulphur, calcium and nitrogen are all higher than the wet deposition loads. Applying a canopy budget model has proven that the routine, simplified canopy throughfall approach may underestimate the dry deposition flux of nitrogen-containing species.

  1. DNA barcoding: species delimitation in tree peonies

    Institute of Scientific and Technical Information of China (English)

    ZHANG JinMei; WANG JianXiu; XIA Tao; ZHOU ShiLiang

    2009-01-01

    Delimitations of species are crucial for correct and precise identification of taxa. Unfortunately "spe-cies" is more a subjective than an objective concept in taxonomic practice due to difficulties in re-vealing patterns of infra- or inter-specific variations. Molecular phylogenetic studies at the population level solve this problem and lay a sound foundation for DNA barcoding. In this paper we exemplify the necessity of adopting a phylogenetic concept of species in DNA barcoding for tree peonies (Paeonia sect. Moutan). We used 40 samples representing all known populations of rare and endangered species and several populations of widely distributed tree peonies. All currently recognized species and majorbvariants have been included in this study. Four chloroplast gene fragments, I.e. ndhF, rps16-trnQ, trnL.F and trnS-G (a total of 5040 characters, 96 variable and 69 parsimony-informative characters) and one variable and single-copy nuclear GPAT gene fragment (2093-2197 bp, 279 variable and 148 parsi-mony-informative characters) were used to construct phylogenetic relationships among the taxa. The evolutionary lineages revealed by the nuclear gene and the chloroplast genes are inconsistent with the current circumscriptions of P. Decomposita, P. Jishanensis, P. Qiui, and P. Rockii based on morphology. The inconsistencies come from (1) significant chloroplast gene divergence but little nuclear GPAT gene divergence among population systems of P. Decomposita + P. Rockii, and (2) well-diverged nuclear GPAT gene but little chloroplast gene divergence between P. Jishanensis and P. Qiui. The incongruence of the phylogenies based on the chloroplast genes and the nuclear GPAT gene is probably due to the chloro-plast capture event in evolutionary history, as no reproductive barriers exist to prevent inter-specific hybridization. We also evaluated the suitability of these genes for use as DNA barcodes for tree peonies. The variability of chloroplast genes among well

  2. Growth strategies of tropical tree species: disentangling light and size effects.

    Directory of Open Access Journals (Sweden)

    Nadja Rüger

    Full Text Available An understanding of the drivers of tree growth at the species level is required to predict likely changes of carbon stocks and biodiversity when environmental conditions change. Especially in species-rich tropical forests, it is largely unknown how species differ in their response of growth to resource availability and individual size. We use a hierarchical bayesian approach to quantify the impact of light availability and tree diameter on growth of 274 woody species in a 50-ha long-term forest census plot in Barro Colorado Island, Panama. Light reaching each individual tree was estimated from yearly vertical censuses of canopy density. The hierarchical bayesian approach allowed accounting for different sources of error, such as negative growth observations, and including rare species correctly weighted by their abundance. All species grew faster at higher light. Exponents of a power function relating growth to light were mostly between 0 and 1. This indicates that nearly all species exhibit a decelerating increase of growth with light. In contrast, estimated growth rates at standardized conditions (5 cm dbh, 5% light varied over a 9-fold range and reflect strong growth-strategy differentiation between the species. As a consequence, growth rankings of the species at low (2% and high light (20% were highly correlated. Rare species tended to grow faster and showed a greater sensitivity to light than abundant species. Overall, tree size was less important for growth than light and about half the species were predicted to grow faster in diameter when bigger or smaller, respectively. Together light availability and tree diameter only explained on average 12% of the variation in growth rates. Thus, other factors such as soil characteristics, herbivory, or pathogens may contribute considerably to shaping tree growth in the tropics.

  3. Quantifying tree mortality in a mixed species woodland using multitemporal high spatial resolution satellite imagery

    Science.gov (United States)

    Garrity, Steven R.; Allen, Craig D.; Brumby, Steven P.; Gangodagamage, Chandana; McDowell, Nate G.; Cai, D. Michael

    2013-01-01

    Widespread tree mortality events have recently been observed in several biomes. To effectively quantify the severity and extent of these events, tools that allow for rapid assessment at the landscape scale are required. Past studies using high spatial resolution satellite imagery have primarily focused on detecting green, red, and gray tree canopies during and shortly after tree damage or mortality has occurred. However, detecting trees in various stages of death is not always possible due to limited availability of archived satellite imagery. Here we assess the capability of high spatial resolution satellite imagery for tree mortality detection in a southwestern U.S. mixed species woodland using archived satellite images acquired prior to mortality and well after dead trees had dropped their leaves. We developed a multistep classification approach that uses: supervised masking of non-tree image elements; bi-temporal (pre- and post-mortality) differencing of normalized difference vegetation index (NDVI) and red:green ratio (RGI); and unsupervised multivariate clustering of pixels into live and dead tree classes using a Gaussian mixture model. Classification accuracies were improved in a final step by tuning the rules of pixel classification using the posterior probabilities of class membership obtained from the Gaussian mixture model. Classifications were produced for two images acquired post-mortality with overall accuracies of 97.9% and 98.5%, respectively. Classified images were combined with land cover data to characterize the spatiotemporal characteristics of tree mortality across areas with differences in tree species composition. We found that 38% of tree crown area was lost during the drought period between 2002 and 2006. The majority of tree mortality during this period was concentrated in piñon-juniper (Pinus edulis-Juniperus monosperma) woodlands. An additional 20% of the tree canopy died or was removed between 2006 and 2011, primarily in areas

  4. Understanding recruitment failure in tropical tree species: Insights from a tree ring study

    NARCIS (Netherlands)

    Vlam, M.; Baker, P.J.; Bunyavejchewin, S.; Mohren, G.M.J.; Zuidema, P.A.

    2014-01-01

    Many tropical tree species have population structures that exhibit strong recruitment failure. While the presence of adult trees indicates that appropriate regeneration conditions occurred in the past, it is often unclear why small individuals are absent. Knowing how, when and where these tree speci

  5. Impacts of tree canopy structure on wind flows and fire propagation simulated with FIRETEC

    OpenAIRE

    Pimont, François; Dupuy, Jean-Luc; Linn, Rodman R.; Dupont, Sylvain

    2011-01-01

    Forest fuel management in the context of fire prevention generally induces heterogeneous spatial patterns of vegetation. However, the impact of the canopy structure on both wind flows and fire behavior is not well understood. Here, a coupled atmosphere wildfire behavior model, HIGRAD/FIRETEC, was used to investigate the effects of canopy treatment on wind field and fire behavior in a typical Mediterranean pine ecosystem. First, the treatment-induced winds were simulated with the model. We obs...

  6. A Study of Ultrasonic Sensors to Intelligent Estimation of Tree Canopy Volumes

    OpenAIRE

    Eskandari, M.; A Hosainpour

    2016-01-01

    Many research projects have been conducted about using ultrasonic sensors to estimate canopy volume. This study investigates using software applications such as artificial neural network (ANN) to improve the estimation of canopy volume by using ultrasonic sensors. A special experimental system was built. The system had three ultrasonic sensors mounted vertically on a wooden pole with an equal distance of 0.6 m. As the wooden pole moves with a constant speed, the ultrasonic sensors measure the...

  7. Simulation of Canopy CO2/H2O Fluxes for a Rubber (Hevea Brasiliensis) Plantation in Central Cambodia: The Effect of the Regular Spacing of Planted Trees

    Energy Technology Data Exchange (ETDEWEB)

    Kumagai, Tomo' omi; Mudd, Ryan; Miyazawa, Yoshiyuki; Liu, Wen; Giambelluca, Thomas; Kobayashi, N.; Lim, Tiva Khan; Jomura, Mayuko; Matsumoto, Kazuho; Huang, Maoyi; Chen, Qi; Ziegler, Alan; Yin, Song

    2013-09-10

    We developed a soil-vegetation-atmosphere transfer (SVAT) model applicable to simulating CO2 and H2O fluxes from the canopies of rubber plantations, which are characterized by distinct canopy clumping produced by regular spacing of plantation trees. Rubber (Hevea brasiliensis Müll. Arg.) plantations, which are rapidly expanding into both climatically optimal and sub-optimal environments throughout mainland Southeast Asia, potentially change the partitioning of water, energy, and carbon at multiple scales, compared with traditional land covers it is replacing. Describing the biosphere-atmosphere exchange in rubber plantations via SVAT modeling is therefore essential to understanding the impacts on environmental processes. The regular spacing of plantation trees creates a peculiar canopy structure that is not well represented in most SVAT models, which generally assumes a non-uniform spacing of vegetation. Herein we develop a SVAT model applicable to rubber plantation and an evaluation method for its canopy structure, and examine how the peculiar canopy structure of rubber plantations affects canopy CO2 and H2O exchanges. Model results are compared with measurements collected at a field site in central Cambodia. Our findings suggest that it is crucial to account for intensive canopy clumping in order to reproduce observed rubber plantation fluxes. These results suggest a potentially optimal spacing of rubber trees to produce high productivity and water use efficiency.

  8. Physiological and foliar symptom response in the crowns of Prunus serotina, Fraxinus americana and Acer rubrum canopy trees to ambient ozone under forest conditions

    International Nuclear Information System (INIS)

    The crowns of five canopy dominant black cherry (Prunus serotina Ehrh.), five white ash (Fraxinus americana L.), and six red maple (Acer rubrum L.) trees on naturally differing environmental conditions were accessed with scaffold towers within a mixed hardwood forest stand in central Pennsylvania. Ambient ozone concentrations, meteorological parameters, leaf gas exchange and leaf water potential were measured at the sites during the growing seasons of 1998 and 1999. Visible ozone-induced foliar injury was assessed on leaves within the upper and lower crown branches of each tree. Ambient ozone exposures were sufficient to induce typical symptoms on cherry (0-5% total affected leaf area, LAA), whereas foliar injury was not observed on ash or maple. There was a positive correlation between increasing cumulative ozone uptake (U) and increasing percent of LAA for cherry grown under drier site conditions. The lower crown leaves of cherry showed more severe foliar injury than the upper crown leaves. No significant differences in predawn leaf water potential (ψL) were detected for all three species indicating no differing soil moisture conditions across the sites. Significant variation in stomatal conductance for water vapor (gwv) was found among species, soil moisture, time of day and sample date. When comparing cumulative ozone uptake and decreased photosynthetic activity (Pn), red maple was the only species to show higher gas exchange under mesic vs. drier soil conditions (P wv and Pn demonstrate the strong influence of heterogeneous environmental conditions within forest canopies. - Within the heterogeneous environment of a mature forest, many factors in addition to soil moisture play a significant role in determining exposure/response relationships to ozone

  9. Assessing the optimal liquid volume to be sprayed on isolated olive trees according to their canopy volumes.

    Science.gov (United States)

    Miranda-Fuentes, A; Llorens, J; Rodríguez-Lizana, A; Cuenca, A; Gil, E; Blanco-Roldán, G L; Gil-Ribes, J A

    2016-10-15

    The application of pesticides to traditional and intensive olive orchards in Southern Spain has led to environmental problems. More specifically, the lack of an accurate, useful criterion to regulate the spray volume in relation to canopy characteristics has led to spray drift and runoff, which are threats to local ecosystems. The aim of this study was to determine the optimal relationship between canopy volume and the spray application volume, called specific spray volume, CV, through laboratory and field trials. In the laboratory trial, 6 specific spray volumes (0.05, 0.08, 0.10, 0.12, 0.15, and 0.20Lm(-3)) were tested in a specially designed structure containing small, live olive trees in order to simulate an intensive plantation system. The model aimed to evaluate the coverage of pesticide application on water sensitive paper (WSP) collectors. In the field trial, the three laboratory specific spray volumes that gave the best coverage values were tested on live, intensively managed trees, whose crown volume was manually measured. Food dye E-102 was used to determine the spray deposition on artificial targets (10×10cm absorbent paper pieces), and WSP was used to evaluate spray coverage. The spray penetration and deposit homogeneity inside the canopy were also evaluated. Weather conditions during the field trial were monitored with a weather station. The results of the laboratory trial showed that the three best specific spray volumes were 0.08, 0.10, and 0.12Lm(-3), resulting in mean coverage values of approximately 30%. The ANOVA of the field trial results showed that the 0.12Lm(-3) was the optimal specific spray volume for isolated olive trees. This specific spray volume gave the highest mean deposits, the best efficiency (as measured by the greatest normalized deposit), the most favourable penetration and homogeneity, and the highest coverage values.

  10. Tree and tree-like species of Mexico: Asteraceae, Leguminosae, and Rubiaceae

    OpenAIRE

    Martin Ricker; Hernández, Héctor M.; Mario Sousa; Helga Ochoterena

    2013-01-01

    Trees or tree-like plants are defined here broadly as perennial, self-supporting plants with a total height of at least 5 m (without ascending leaves or inflorescences), and with one or several erect stems with a diameter of at least 10 cm. We continue our compilation of an updated list of all native Mexican tree species with the dicotyledonous families Asteraceae (36 species, 39% endemic), Leguminosae with its 3 subfamilies (449 species, 41% endemic), and Rubiaceae (134 species, 24% endemic)...

  11. A polynomial time algorithm for calculating the probability of a ranked gene tree given a species tree

    OpenAIRE

    Stadler, Tanja; Degnan, James H

    2012-01-01

    Background The ancestries of genes form gene trees which do not necessarily have the same topology as the species tree due to incomplete lineage sorting. Available algorithms determining the probability of a gene tree given a species tree require exponential computational runtime. Results In this paper, we provide a polynomial time algorithm to calculate the probability of a ranked gene tree topology for a given species tree, where a ranked tree topology is a tree topology with the internal v...

  12. Prioritizing Preferable Locations for Increasing Urban Tree Canopy in New York City

    OpenAIRE

    Dexter H. Locke; J. Morgan Grove; Lu, Jacqueline W.T.; Austin Troy; Jarlath P.M. O'Neil-Dunne; Beck, Brian D.

    2010-01-01

    This paper presents a set of Geographic Information System (GIS) methods for identifying and prioritizing tree planting sites in urban environments. It uses an analytical approach created by a University of Vermont service-learning class called “GIS Analysis of New York City's Ecology” that was designed to provide research support to the MillionTreesNYC tree planting campaign. These methods prioritize tree planting sites based on need (whether or not trees can help address specific issues in ...

  13. Leaf reflectance variation along a vertical crown gradient of two deciduous tree species in a Belgian industrial habitat

    International Nuclear Information System (INIS)

    The reflectometry of leaf asymmetry is a novel approach in the bio-monitoring of tree health in urban or industrial habitats. Leaf asymmetry responds to the degree of environmental pollution and reflects structural changes in a leaf due to environmental pollution. This paper describes the boundary conditions to scale up from leaf to canopy level reflectance, by describing the variability of adaxial and abaxial leaf reflectance, hence leaf asymmetry, along the crown height gradients of two tree species. Our findings open a research pathway towards bio-monitoring based on the airborne remote sensing of tree canopies and their leaf asymmetric properties. - Highlights: • Reflectometry of leaf asymmetry is a novel approach in tree health bio-monitoring. • Leaf asymmetry reflects degrees of structural changes by environmental pollution. • Conditions to scale up from leaf to canopy level reflectance are described. • A research pathway is opened towards airborne pollution bio-assessment. - Tree leaf asymmetry responds to the degree of environmental pollution and reflects leaf structural changes differentially according to species and height in the crown

  14. Effects of the pear tree canopy on photosynthetically active radiation availability

    International Nuclear Information System (INIS)

    The relationships existing between radiant energy and photosynthesis have been extensively investigated on the apple /2/ but not on the other fruit trees, pear included. In addition, such information resists generalization, owing to the remarkable differences underlying tree morphology and physiology of the different species; furthermore, some disagreement arises regarding the terminology and the units used to evaluate the amount of radiant energy useful for the photosynthetic process. In general this evaluation is based on the readouts of illuminance (symbol Ev; unit: lux), in agreement with the photopic curve (fig. 1:A), i.e. with the human eye sensibility to the visible radiation(light). However, the relative response of the chloroplasts to the radiant flux, although included within the same spectral wavebands as the photopic curve, follows a different model (fig.1:B), that is, it has two peaks in connection with the spectral wavelenghts of blue (440–490 nm), and, particularly, of red (620–700 nm). Therefore, according to a number of authors /3/6/8/11/, the correct evaluation of the photosynthetically active radiation should be made using sensors calibrated to measure the photosynthetic photon lux density (symbol: PPFD; unit: μE m-2s-1), and provided with a relative spectral response similar to that of the leaves. (author)

  15. Segmentation and classification of high resolution imagery for mapping individual species in a closed canopy, deciduous forest

    Institute of Scientific and Technical Information of China (English)

    Timothy; A.; Warner; James; B.; McGraw; Rick; Landenberger

    2006-01-01

    In this paper we investigate the use of a shadow-based delineation program for identifying segments in imagery of a closed canopy, deciduous forest, in West Virginia, USA, as a way to reduce the noise associated with per-pixel classification in forested environments. Shadows typically cluster along the boundaries of trees and therefore can be used to provide a network of nodes for the delineation of segments. A minimum cost path algorithm, where cost is defined as the cumulative sum of brightness values traversed along the connecting route, was used to connect shadow clumps. To test this approach, a series of classifications was undertaken using a multispectral digital aerial image of a six hectare test site and a minimum cost path segmentation. Three species were mapped: oaks, red maple and yellow poplar. The accuracy of an aspatial maximum likelihood classification (termed PERPIXEL classification) was 68.5%, compared to 74.0% for classification using the mean vector of the segments identified with the minimum cost path algorithm (MEAN_SEG), and 78% when the most common class present in the segment is assigned to the entire segment (POSTCLASS_SEG). By comparison, multispectral classification of the multispectral data using the field-mapped polygons of individual trees as segments, produced an accuracy of 82.3% when the mean vector of the polygon was used for classification (MEAN_TREE), and 85.7% when the most common class was assigned to the entire polygon (POSTCLASS_TREE). A moving window-based post-classification majority filter (POSTCLASS_MAJ5BY5) produced an intermediate accuracy value, 73.8%. The minimum cost path segmentation algorithm was found to correctly delineate approximately 28% of the trees. The remaining trees were either segmented, aggregated, or a combination of both segmented and aggregated. Varying the threshold that was used to discriminate shadows appeared to have little effect on the number of correctly delineated trees, or on the overall

  16. TREE SPECIES DIRECT SOWING FOR FOREST RESTORATION

    Directory of Open Access Journals (Sweden)

    Robério Anastácio Ferreira

    2007-09-01

    Full Text Available The direct sowing to tropical forest restoration can be viable when the ecological and silvicultural aspects of species areknown. This work evaluated the effect of breaking seed dormancy and a physical protector on the initial growth of riparian treespecies. The experiment was carried out in a randomized blocks design, in a factorial (2x2, with four blocks and four plots for eachtreatment. The treatment to break seed dormancy used were: immersion in sulphuric acid for 20 minutes and washing in water for 1hour plus soaking for 24 hours for Trema micrantha; immersion in boiling water (100oC with following soaking until refreshing for24 hours to Senna multijuga and Senna macranthera and pre-soaking in water for 2 hours for Solanum granuloso-leprosum. Thephysical protector used was a transparent plastic cup (500mL. The breaking seed dormancy used was efficient in laboratory, exceptfor S. macranthera. In field conditions, it was efficient only for S. multijuga and S. macranthera. The physical protector did notpresented any benefit for the studied tree species regarding seedlings emergence and survival, but it provided significant differencesin height and base diameter for S. multijuga and in height for S. macranthera after three months. After 24 months, T. micranthapresented the highest values for height and basal diameter. S. macranthera presented the height relative growth and T. micrantha thehighest basal diameter. The studied species can be recommended for ecological forest restoration, using direct sowing.

  17. Effects of Tree Species Diversity on Insect Herbivory

    OpenAIRE

    Morath, Simon

    2013-01-01

    It is generally believed that tree species growing in mixed forest stands are less susceptible to insect herbivore damage than if grown in monocultures, but previous studies have been largely observational and focussed mainly on tree species richness effects. In this thesis, I examined effects of three components of forest diversity (tree species richness, intraspecific genotypic diversity and functional diversity) on insect herbivores using three long-term forest diversity experiments in Fin...

  18. Cryptococcus neoformans varieties from material under the canopies of eucalyptus trees and pigeon dropping samples from four major cities in Jordan.

    Science.gov (United States)

    Hamasha, Akram Mohammad Saad; Yildiran, Sinasi Taner; Gonlum, Ahmet; Saracli, Mehmet Ali; Doganci, Levent

    2004-08-01

    To our best knowledge, any study related to the ecological distribution of Cryptococcus neoformans in Jordan does not exist in the medical literature. In order to determine the environmental occurrence of both varieties of Cryptococcus neoformans in Jordan, pigeon droppings and material under the canopies of eucalyptus trees were collected from four major cities of this country. For the isolation of Cryptococcus neoformans variety gattii from environmental sources, 500 samples of the mixed soil debris, including tree materials, under the eucalyptus trees from cities of Amman, Irbid, Jerash, and Ajlun were collected. Also, 509 samples of pigeon droppings were collected from the same cities for the isolation of Cryptococcus neoformans variety neoformans. After inoculating the samples onto modified Staib agar medium in Petri dishes, a total of 336 melanoid yeast colonies were picked up during screening process. At the end of serial mycological studies, none of these isolates was identified as Cryptococcus neoformans, but all were Cryptococcus species other than C. neoformans. For determining the exact status, more extensive environmental studies need to be done in the future. PMID:15518348

  19. A Versatile, Production-Oriented Approach to High-Resolution Tree-Canopy Mapping in Urban and Suburban Landscapes Using GEOBIA and Data Fusion

    Directory of Open Access Journals (Sweden)

    Jarlath O'Neil-Dunne

    2014-12-01

    Full Text Available The benefits of tree canopy in urban and suburban landscapes are increasingly well known: stormwater runoff control, air-pollution mitigation, temperature regulation, carbon storage, wildlife habitat, neighborhood cohesion, and other social indicators of quality of life. However, many urban areas lack high-resolution tree canopy maps that document baseline conditions or inform tree-planting programs, limiting effective study and management. This paper describes a GEOBIA approach to tree-canopy mapping that relies on existing public investments in LiDAR, multispectral imagery, and thematic GIS layers, thus eliminating or reducing data acquisition costs. This versatile approach accommodates datasets of varying content and quality, first using LiDAR derivatives to identify aboveground features and then a combination of LiDAR and imagery to differentiate trees from buildings and other anthropogenic structures. Initial tree canopy objects are then refined through contextual analysis, morphological smoothing, and small-gap filling. Case studies from locations in the United States and Canada show how a GEOBIA approach incorporating data fusion and enterprise processing can be used for producing high-accuracy, high-resolution maps for large geographic extents. These maps are designed specifically for practical application by planning and regulatory end users who expect not only high accuracy but also high realism and visual coherence.

  20. Fully Automated Gis-Based Individual Tree Crown Delineation Based on Curvature Values from a LIDAR Derived Canopy Height Model in a Coniferous Plantation

    Science.gov (United States)

    Argamosa, R. J. L.; Paringit, E. C.; Quinton, K. R.; Tandoc, F. A. M.; Faelga, R. A. G.; Ibañez, C. A. G.; Posilero, M. A. V.; Zaragosa, G. P.

    2016-06-01

    The generation of high resolution canopy height model (CHM) from LiDAR makes it possible to delineate individual tree crown by means of a fully-automated method using the CHM's curvature through its slope. The local maxima are obtained by taking the maximum raster value in a 3 m x 3 m cell. These values are assumed as tree tops and therefore considered as individual trees. Based on the assumptions, thiessen polygons were generated to serve as buffers for the canopy extent. The negative profile curvature is then measured from the slope of the CHM. The results show that the aggregated points from a negative profile curvature raster provide the most realistic crown shape. The absence of field data regarding tree crown dimensions require accurate visual assessment after the appended delineated tree crown polygon was superimposed to the hill shaded CHM.

  1. FULLY AUTOMATED GIS-BASED INDIVIDUAL TREE CROWN DELINEATION BASED ON CURVATURE VALUES FROM A LIDAR DERIVED CANOPY HEIGHT MODEL IN A CONIFEROUS PLANTATION

    Directory of Open Access Journals (Sweden)

    R. J. L. Argamosa

    2016-06-01

    Full Text Available The generation of high resolution canopy height model (CHM from LiDAR makes it possible to delineate individual tree crown by means of a fully-automated method using the CHM’s curvature through its slope. The local maxima are obtained by taking the maximum raster value in a 3 m x 3 m cell. These values are assumed as tree tops and therefore considered as individual trees. Based on the assumptions, thiessen polygons were generated to serve as buffers for the canopy extent. The negative profile curvature is then measured from the slope of the CHM. The results show that the aggregated points from a negative profile curvature raster provide the most realistic crown shape. The absence of field data regarding tree crown dimensions require accurate visual assessment after the appended delineated tree crown polygon was superimposed to the hill shaded CHM.

  2. Tree species richness affecting fine root biomass in European forests

    Science.gov (United States)

    Finér, Leena; Domisch, Timo; Vesterdal, Lars; Dawud, Seid M.; Raulund-Rasmussen, Karsten

    2016-04-01

    Fine roots are an important factor in the forest carbon cycle, contributing significantly to below-ground biomass and soil carbon storage. Therefore it is essential to understand the role of the forest structure, indicated by tree species diversity in controlling below-ground biomass and managing the carbon pools of forest soils. We studied how tree species richness would affect fine root biomass and its distribution in the soil profile and biomass above- and below-ground allocation patterns of different tree species. Our main hypothesis was that increasing tree species richness would lead to below-ground niche differentiation and more efficient soil exploitation by the roots, resulting in a higher fine root biomass in the soil. We sampled fine roots of trees and understorey vegetation in six European forest types in Finland, Poland, Germany, Romania, Italy and Spain, representing boreal, temperate and Mediterranean forests, established within the FunDivEUROPE project for studying the effects of tree species diversity on forest functioning. After determining fine root biomasses, we identified the percentages of different tree species in the fine root samples using the near infrared reflectance spectroscopy (NIRS) method. Opposite to our hypothesis we did not find any general positive relationship between tree species richness and fine root biomass. A weak positive response found in Italy and Spain seemed to be related to dry environmental conditions during Mediterranean summers. At the Polish site where we could sample deeper soil layers (down to 40 cm), we found more tree fine roots in the deeper layers under species-rich forests, as compared to the monocultures, indicating the ability of trees to explore more resources and to increase soil carbon stocks. Tree species richness did not affect biomass allocation patterns between above- and below-ground parts of the trees.

  3. Foliar respiration and its temperature sensitivity in trees and lianas: in situ measurements in the upper canopy of a tropical forest.

    Science.gov (United States)

    Slot, Martijn; Wright, S Joseph; Kitajima, Kaoru

    2013-05-01

    Leaf dark respiration (R) and its temperature sensitivity are essential for efforts to model carbon fluxes in tropical forests under current and future temperature regimes, but insufficient data exist to generalize patterns of R in species-rich tropical forests. Here, we tested the hypothesis that R and its temperature sensitivity (expressed as Q10, the proportional increase in R with a 10 °C rise in temperature) vary in relation to leaf functional traits, and among plant functional types (PFTs). We conducted in situ measurements of R of 461 leaves of 26 species of tree and liana in the upper canopy of a tropical forest in Panama. A construction crane allowed repeated non-destructive access to measure leaves kept in the dark since the previous night and equilibrated to the ambient temperature of 23-31 °C in the morning. R at 25 °C (R25) varied among species (mean 1.11 μmol m(-2) s(-1); range 0.72-1.79 μmol m(-2) s(-1)) but did not differ significantly among PFTs. R25 correlated positively with photosynthetic capacity, leaf mass per unit area, concentrations of nitrogen and phosphorus, and negatively with leaf lifespan. Q10 estimated for each species was on average higher than the 2.0 often assumed in coupled climate-vegetation models (mean 2.19; range 1.24-3.66). Early-successional tree species had higher Q10 values than other functional types, but interspecific variation in Q10 values was not correlated with other leaf traits. Similarity in respiration characteristics across PFTs, and relatively strong correlations of R with other leaf functional traits offer potential for trait-based vegetation modeling in species-rich tropical forests. PMID:23592296

  4. STBase: one million species trees for comparative biology.

    Directory of Open Access Journals (Sweden)

    Michelle M McMahon

    Full Text Available Comprehensively sampled phylogenetic trees provide the most compelling foundations for strong inferences in comparative evolutionary biology. Mismatches are common, however, between the taxa for which comparative data are available and the taxa sampled by published phylogenetic analyses. Moreover, many published phylogenies are gene trees, which cannot always be adapted immediately for species level comparisons because of discordance, gene duplication, and other confounding biological processes. A new database, STBase, lets comparative biologists quickly retrieve species level phylogenetic hypotheses in response to a query list of species names. The database consists of 1 million single- and multi-locus data sets, each with a confidence set of 1000 putative species trees, computed from GenBank sequence data for 413,000 eukaryotic taxa. Two bodies of theoretical work are leveraged to aid in the assembly of multi-locus concatenated data sets for species tree construction. First, multiply labeled gene trees are pruned to conflict-free singly-labeled species-level trees that can be combined between loci. Second, impacts of missing data in multi-locus data sets are ameliorated by assembling only decisive data sets. Data sets overlapping with the user's query are ranked using a scheme that depends on user-provided weights for tree quality and for taxonomic overlap of the tree with the query. Retrieval times are independent of the size of the database, typically a few seconds. Tree quality is assessed by a real-time evaluation of bootstrap support on just the overlapping subtree. Associated sequence alignments, tree files and metadata can be downloaded for subsequent analysis. STBase provides a tool for comparative biologists interested in exploiting the most relevant sequence data available for the taxa of interest. It may also serve as a prototype for future species tree oriented databases and as a resource for assembly of larger species phylogenies

  5. Robustness to divergence time underestimation when inferring species trees from estimated gene trees.

    Science.gov (United States)

    DeGiorgio, Michael; Degnan, James H

    2014-01-01

    To infer species trees from gene trees estimated from phylogenomic data sets, tractable methods are needed that can handle dozens to hundreds of loci. We examine several computationally efficient approaches-MP-EST, STAR, STEAC, STELLS, and STEM-for inferring species trees from gene trees estimated using maximum likelihood (ML) and Bayesian approaches. Among the methods examined, we found that topology-based methods often performed better using ML gene trees and methods employing coalescent times typically performed better using Bayesian gene trees, with MP-EST, STAR, STEAC, and STELLS outperforming STEM under most conditions. We examine why the STEM tree (also called GLASS or Maximum Tree) is less accurate on estimated gene trees by comparing estimated and true coalescence times, performing species tree inference using simulations, and analyzing a great ape data set keeping track of false positive and false negative rates for inferred clades. We find that although true coalescence times are more ancient than speciation times under the multispecies coalescent model, estimated coalescence times are often more recent than speciation times. This underestimation can lead to increased bias and lack of resolution with increased sampling (either alleles or loci) when gene trees are estimated with ML. The problem appears to be less severe using Bayesian gene-tree estimates.

  6. Seedling traits determine drought tolerance of tropical tree species

    NARCIS (Netherlands)

    Poorter, L.; Markesteijn, L.

    2008-01-01

    Water availability is the most important factor determining tree species distribution in the tropics, but the underlying mechanisms are still not clear. In this study, we compared functional traits of 38 tropical tree species from dry and moist forest, and quantified their ability to survive drought

  7. Seasonal drought limits tree species across the Neotropics

    NARCIS (Netherlands)

    Esquivel-Muelbert, Adriane; Baker, Timothy R.; Dexter, Kyle G.; Lewis, Simon L.; Steege, ter Hans; Lopez-Gonzalez, Gabriela; Monteagudo Mendoza, Abel; Brienen, Roel; Feldpausch, Ted R.; Pitman, Nigel; Alonso, Alfonso; Heijden, van der Geertje; Peña-Claros, Marielos; Ahuite, Manuel; Alexiaides, Miguel; Álvarez Dávila, Esteban; Murakami, Alejandro Araujo; Arroyo, Luzmila; Aulestia, Milton; Balslev, Henrik; Barroso, Jorcely; Boot, Rene; Cano, Angela; Chama Moscoso, Victor; Comiskey, James A.; Cornejo, Fernando; Dallmeier, Francisco; Daly, Douglas C.; Dávila, Nallarett; Duivenvoorden, Joost F.; Duque Montoya, Alvaro Javier; Erwin, Terry; Fiore, Di Anthony; Fredericksen, Todd; Fuentes, Alfredo; García-Villacorta, Roosevelt; Gonzales, Therany; Guevara Andino, Juan Ernesto; Honorio Coronado, Euridice N.; Huamantupa-Chuquimaco, Isau; Killeen, Timothy J.; Malhi, Yadvinder; Mendoza, Casimiro; Mogollón, Hugo; Jørgensen, Peter Møller; Montero, Juan Carlos; Mostacedo, Bonifacio; Nauray, William; Neill, David; Vargas, Percy Núñez; Palacios, Sonia; Palacios Cuenca, Walter; Pallqui Camacho, Nadir Carolina; Peacock, Julie; Phillips, Juan Fernando; Pickavance, Georgia; Quesada, Carlos Alberto; Ramírez-Angulo, Hirma; Restrepo, Zorayda; Reynel Rodriguez, Carlos; Paredes, Marcos Ríos; Sierra, Rodrigo; Silveira, Marcos; Stevenson, Pablo; Stropp, Juliana; Terborgh, John; Tirado, Milton; Toledo, Marisol; Torres-Lezama, Armando; Umaña, María Natalia; Urrego, Ligia Estela; Vasquez Martinez, Rodolfo; Gamarra, Luis Valenzuela; Vela, César I.A.; Vilanova Torre, Emilio; Vos, Vincent; Hildebrand, von Patricio; Vriesendorp, Corine; Wang, Ophelia; Young, Kenneth R.; Zartman, Charles Eugene; Phillips, Oliver L.

    2016-01-01

    Within the tropics, the species richness of tree communities is strongly and positively associated with precipitation. Previous research has suggested that this macroecological pattern is driven by the negative effect of water-stress on the physiological processes of most tree species. This impli

  8. Continental-scale patterns of canopy tree composition and function across Amazonia

    Science.gov (United States)

    Ter Steege, Hans; Pitman, Nigel C. A.; Phillips, Oliver L.; Chave, Jerome; Sabatier, Daniel; Duque, Alvaro; Molino, Jean-François; Prévost, Marie-Françoise; Spichiger, Rodolphe; Castellanos, Hernán; von Hildebrand, Patricio; Vásquez, Rodolfo

    2006-09-01

    The world's greatest terrestrial stores of biodiversity and carbon are found in the forests of northern South America, where large-scale biogeographic patterns and processes have recently begun to be described. Seven of the nine countries with territory in the Amazon basin and the Guiana shield have carried out large-scale forest inventories, but such massive data sets have been little exploited by tropical plant ecologists. Although forest inventories often lack the species-level identifications favoured by tropical plant ecologists, their consistency of measurement and vast spatial coverage make them ideally suited for numerical analyses at large scales, and a valuable resource to describe the still poorly understood spatial variation of biomass, diversity, community composition and forest functioning across the South American tropics. Here we show, by using the seven forest inventories complemented with trait and inventory data collected elsewhere, two dominant gradients in tree composition and function across the Amazon, one paralleling a major gradient in soil fertility and the other paralleling a gradient in dry season length. The data set also indicates that the dominance of Fabaceae in the Guiana shield is not necessarily the result of root adaptations to poor soils (nodulation or ectomycorrhizal associations) but perhaps also the result of their remarkably high seed mass there as a potential adaptation to low rates of disturbance.

  9. 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.

  10. 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. PMID:26594707

  11. Tree architecture of pillar and standard peach affect canopy transpiration and water use efficiency

    Science.gov (United States)

    The development of productive high density peach orchards is often limited by the excessive vegetative growth of the trees that reduces productivity and quality. Dwarfing rootstocks are not available but upright tree architectures have been developed for high density peach production. The purpose ...

  12. Summertime canopy albedo is sensitive to forest thinning

    OpenAIRE

    Otto, J.; Berveiller, D.; F.-M. Bréon; Delpierre, N.; Geppert, G.; Granier, A.; Jans, W.; Knohl, A; Kuusk, A.; B. Longdoz; Moors, E.; Mund, M.; Pinty, B.; M.-J. Schelhaas; Luyssaert, S.

    2013-01-01

    Despite an emerging body of literature linking canopy albedo to forest management, understanding of the process is still fragmented. We combined a stand-level forest gap model with a canopy radiation transfer model and satellite-derived model parameters to quantify the effects of forest thinning, that is removing trees at a certain time during the forest rotation, on summertime canopy albedo. The effects of different forest species (pine, beech, oak) and four thinning strategies (light to int...

  13. Canopy recovery of pedunculate oak, Turkey oak and beech trees after severe defoliation by gypsy moth (Lymantria dispar: Case study from Western Hungary

    Directory of Open Access Journals (Sweden)

    Csóka György

    2015-09-01

    Full Text Available We investigated the canopy recovery of 3 tree species (pedunculate oak, Turkey oak, European beech at two locations in the Veszprém county (Western Hungary after severe defoliation by gypsy moth caterpillars in the spring of 2005. The Turkey oak has evidently the best recovery potential, and it almost completely replaced the lost foliage in 4 months. The pedunculate oak and beech needed 2 years to reach the same level of recovery. The pedunculate oak suffered from a heavy infection of Microsphaera alphitoides after defoliation and it probably slowed down its recovery. Neither the presence of Agrilus biguttatus in the oak plot nor the appearance of Agrilus viridis in the beech plot was observed during the study period. Population density of the buprestid Coraebus floerentinus showed a considerable increase in the oak plot, but remained under the damage level. Neither other harmful appearance of other pests nor significant tree mortality were observed within 4 years from the defoliation. These results provide information for the evaluation of longer term influences of the gypsy moth defoliation and may support the decisions concerning pest control.

  14. Factors affecting the concordance between orthologous gene trees and species tree in bacteria

    Directory of Open Access Journals (Sweden)

    González Víctor

    2008-10-01

    Full Text Available Abstract Background As originally defined, orthologous genes implied a reflection of the history of the species. In recent years, many studies have examined the concordance between orthologous gene trees and species trees in bacteria. These studies have produced contradictory results that may have been influenced by orthologous gene misidentification and artefactual phylogenetic reconstructions. Here, using a method that allows the detection and exclusion of false positives during identification of orthologous genes, we address the question of whether putative orthologous genes within bacteria really reflect the history of the species. Results We identified a set of 370 orthologous genes from the bacterial order Rhizobiales. Although manifesting strong vertical signal, almost every orthologous gene had a distinct phylogeny, and the most common topology among the orthologous gene trees did not correspond with the best estimate of the species tree. However, each orthologous gene tree shared an average of 70% of its bipartitions with the best estimate of the species tree. Stochastic error related to gene size affected the concordance between the best estimated of the species tree and the orthologous gene trees, although this effect was weak and distributed unevenly among the functional categories. The nodes showing the greatest discordance were those defined by the shortest internal branches in the best estimated of the species tree. Moreover, a clear bias was evident with respect to the function of the orthologous genes, and the degree of divergence among the orthologous genes appeared to be related to their functional classification. Conclusion Orthologous genes do not reflect the history of the species when taken as individual markers, but they do when taken as a whole. Stochastic error affected the concordance of orthologous genes with the species tree, albeit weakly. We conclude that two important biological causes of discordance among

  15. Seasonal drought limits tree species across the Neotropics

    OpenAIRE

    Esquivel Muelbert, Adriane; Baker, Timothy; Dexter, Kyle; Lewis, Simon; Ter Steege, Hans; Lopez-Gonzales, Gabriela; Monteagudo Mendoza, Abel; Brienen, Roel J.W.; Feldpausch, Ted R.; Pitman, Nigel; Alonso, Alfonso; van der Heijden, Geertje M. F.; Pena-Claros, Marielos; Ahuite, Manuel; Alexiaides, Miguel

    2016-01-01

    Within the tropics, the species richness of tree communities is strongly and positively associated with precipitation. Previous research has suggested that this macroecological pattern is driven by the negative effect of water-stress on the physiological processes of most tree species. This process implies that the range limits of taxa are defined by their ability to occur under dry conditions, and thus in terms of species distributions it predicts a nested pattern of taxa distribution from w...

  16. Evidence of tree species' range shifts in a complex landscape.

    Directory of Open Access Journals (Sweden)

    Vicente J Monleon

    Full Text Available Climate change is expected to change the distribution of species. For long-lived, sessile species such as trees, tracking the warming climate depends on seedling colonization of newly favorable areas. We compare the distribution of seedlings and mature trees for all but the rarest tree species in California, Oregon and Washington, United States of America, a large, environmentally diverse region. Across 46 species, the mean annual temperature of the range of seedlings was 0.120°C colder than that of the range of trees (95% confidence interval from 0.096 to 0.144°C. The extremes of the seedling distributions also shifted towards colder temperature than those of mature trees, but the change was less pronounced. Although the mean elevation and mean latitude of the range of seedlings was higher than and north of those of the range of mature trees, elevational and latitudinal shifts run in opposite directions for the majority of the species, reflecting the lack of a direct biological relationship between species' distributions and those variables. The broad scale, environmental diversity and variety of disturbance regimes and land uses of the study area, the large number and exhaustive sampling of tree species, and the direct causal relationship between the temperature response and a warming climate, provide strong evidence to attribute the observed shifts to climate change.

  17. Mycorrhizal networks counteract competitive effects of canopy trees on seedling survival.

    Science.gov (United States)

    Booth, Michael G; Hoeksema, Jason D

    2010-08-01

    The dynamics of forest ecosystems depend largely on the survival of seedlings in their understories, but seedling survival is known to be limited by preemption of light and soil resources by overstory trees. It has been hypothesized that "common mycorrhizal networks," wherein roots of seedlings are linked to overstory trees by symbiotic mycorrhizal fungi, offset some or all of the negative effects of trees on seedlings. Here we report the results of an unambiguous experimental test of this hypothesis in a monodominant Pinus radiata forest. We also tested the hypothesis that adaptive differentiation among plant populations causes local plant genotypes to respond more positively to mycorrhizal networks than nonlocal plant genotypes. Our results demonstrate large positive effects of overstory mycorrhizal networks on seedling survival, along with simultaneous negative effects of tree roots, regardless of whether plant genotypes were locally derived. Physiological and leaf-chemistry measurements suggest that seedlings connected to common mycorrhizal networks benefited from increased access to soil water. The similar magnitude of the positive and negative overstory effects on seedlings and the ubiquity of mycorrhizal networks in forests suggest that mycorrhizal networks fundamentally influence the demographic and community dynamics of forest trees. PMID:20836451

  18. Changes in canopy structure and ant assemblages affect soil ecosystem variables as a foundation species declines

    OpenAIRE

    Ellison, Aaron M.; Kendrick, J.A.; Classen, A.T.; Ribbons, R.R.

    2015-01-01

    The decline of Tsuga canadensis (eastern hemlock) – a foundation tree species – due to infestation by Adelges tsugae (hemlock woolly adelgid) or its complete removal from a stand by salvage logging dramatically affects associated faunal assemblages. Among these assemblages, species composition (richness and abundance) of ants increases rapidly as T. canadensis is lost from the stands. Because ants live and forage at the litter-soil interface, we hypothesized that environmental changes caused ...

  19. The role of exotic tree species in Nordic forestry

    DEFF Research Database (Denmark)

    Kjær, Erik Dahl; Lobo, Albin; Myking, Tor

    2014-01-01

    The selection of suitable tree species is a prerequisite for successful forestry, and the use of exotic species as an alternative to native species is often a relevant option. In this paper, we discuss this option in relation to the present and future wood production in Nordic forestry. We revisi...

  20. Effects of single-tree selection harvesting on hymenopteran and saproxylic insect assemblages in the canopy and understory of northern temperate forests

    Institute of Scientific and Technical Information of China (English)

    Sandy M.Smith; Nurul Islam; M.Isabel Bellocq

    2012-01-01

    Insects respond to changes in microhabitat caused by canopy disturbance,and thus can be used to examine the ecological impacts of harvesting.Single-tree selection harvesting is the most common silvicultural system used to emulate local small-scale natural disturbance and maintain uneven-aged forest structure in temperate forests.Here,we test for differences in richness,abundance,and composition of hymenopteran and saproxylic insect assemblages at four different taxon levels (selected insect orders; and all hymenopteran families,and braconid subfamilies and morphospecies) between the canopy and understory of unharvested and single-tree selection harvested sites in a northern temperate forest from central Canada.Harvesting had no effect on insect assemblage richness,composition or abundance at the three highest taxon levels (order,family and subfamily).Similarly,richness and abundance at the lowest-taxon level (braconid morphospecies) were similar,although composition differed slightly between unharvested and harvested stands.Insect assemblages were vertically stratified,with generally higher abundance (for Diptera,Hymenoptera,some hymenopteran families and braconid subfamilies) and richness (for braconid morphospecies) in the understory than the canopy.In particular,composition of the braconid morphospecies assemblage showed relatively low similarity between the understory and canopy.Single-tree selection harvesting appears to influence wood-associated insect taxa only subtly through small changes in community composition at the lowest taxon level,and thus is recommended as a conservative approach for managing these northern temperate forests.

  1. Indirect interactions among tropical tree species through shared rodent seed predators: a novel mechanism of tree species coexistence

    NARCIS (Netherlands)

    Garzon-Lopez, C.X.; Ballesteros-Mejia, L.; Ordonez, A.; Bohlman, S.A.; Olff, H.; Jansen, P.A.

    2015-01-01

    The coexistence of numerous tree species in tropical forests is commonly explained by negative dependence of recruitment on the conspecific seed and tree density due to specialist natural enemies that attack seeds and seedlings (‘Janzen–Connell’ effects). Less known is whether guilds of shared seed

  2. Indirect interactions among tropical tree species through shared rodent seed predators : A novel mechanism of tree species coexistence

    NARCIS (Netherlands)

    Garzon-Lopez, Carol X; Ballesteros-Mejia, Liliana; Ordoñez, Alejandro; Bohlman, Stephanie A; Olff, Han; Jansen, Patrick A

    2015-01-01

    The coexistence of numerous tree species in tropical forests is commonly explained by negative dependence of recruitment on the conspecific seed and tree density due to specialist natural enemies that attack seeds and seedlings ('Janzen-Connell' effects). Less known is whether guilds of shared seed

  3. Comparative assessment of methods for estimating tree canopy cover across a rural-to-urban gradient in the mid-Atlantic region of the USA.

    Science.gov (United States)

    Riemann, Rachel; Liknes, Greg; O'Neil-Dunne, Jarlath; Toney, Chris; Lister, Tonya

    2016-05-01

    Tree canopy cover significantly affects human and wildlife habitats, local hydrology, carbon cycles, fire behavior, and ecosystem services of all types. In addition, changes in tree canopy cover are both indicators and consequences of a wide variety of disturbances from urban development to climate change. There is growing demand for this information nationwide and across all land uses. The extensive inventory plot system managed by the USDA Forest Service Forest Inventory and Analysis (FIA) offers a unique opportunity for acquiring unbiased tree canopy cover information across broad areas. However, the estimates it produces had not yet been examined for comparative accuracy with other sources. In this study, we compared four different methods readily available and with significant potential for application over broad areas. The first two, field-collected and photointerpreted, are currently acquired by FIA on approximately 44,000 plots annually nationwide. The third method is a stem-mapping approach that models tree canopy cover from variables regularly measured on forested plots and is efficient enough to calculate nationwide. The fourth is a Geographic-Object-Based Image Analysis (GEOBIA) approach that uses both high-resolution imagery and leaf-off LiDAR data and has reported very high accuracies and spatial detail at state-wide levels of application. Differences in the spatial and temporal resolution and coverage of these four datasets suggest that they could provide complementary information if their relationships could be better understood. Plot- and county-level estimates of tree canopy cover derived from each of the four data sources were compared for 11 counties in Maryland, Pennsylvania, and West Virginia across a range of urbanization levels. We found high levels of systematic agreement between field and photointerpreted, stem-mapped and field, photointerpreted and GEOBIA estimates. In several cases, the relationship changed with the level of tree canopy

  4. Comparative assessment of methods for estimating tree canopy cover across a rural-to-urban gradient in the mid-Atlantic region of the USA.

    Science.gov (United States)

    Riemann, Rachel; Liknes, Greg; O'Neil-Dunne, Jarlath; Toney, Chris; Lister, Tonya

    2016-05-01

    Tree canopy cover significantly affects human and wildlife habitats, local hydrology, carbon cycles, fire behavior, and ecosystem services of all types. In addition, changes in tree canopy cover are both indicators and consequences of a wide variety of disturbances from urban development to climate change. There is growing demand for this information nationwide and across all land uses. The extensive inventory plot system managed by the USDA Forest Service Forest Inventory and Analysis (FIA) offers a unique opportunity for acquiring unbiased tree canopy cover information across broad areas. However, the estimates it produces had not yet been examined for comparative accuracy with other sources. In this study, we compared four different methods readily available and with significant potential for application over broad areas. The first two, field-collected and photointerpreted, are currently acquired by FIA on approximately 44,000 plots annually nationwide. The third method is a stem-mapping approach that models tree canopy cover from variables regularly measured on forested plots and is efficient enough to calculate nationwide. The fourth is a Geographic-Object-Based Image Analysis (GEOBIA) approach that uses both high-resolution imagery and leaf-off LiDAR data and has reported very high accuracies and spatial detail at state-wide levels of application. Differences in the spatial and temporal resolution and coverage of these four datasets suggest that they could provide complementary information if their relationships could be better understood. Plot- and county-level estimates of tree canopy cover derived from each of the four data sources were compared for 11 counties in Maryland, Pennsylvania, and West Virginia across a range of urbanization levels. We found high levels of systematic agreement between field and photointerpreted, stem-mapped and field, photointerpreted and GEOBIA estimates. In several cases, the relationship changed with the level of tree canopy

  5. Soil Terpene Emissions in a Subalpine Coniferous Forest: Tree Species, Soil Temperature and Moisture Effects

    Science.gov (United States)

    Asensio, D.; Duhl, T.; Greenberg, J.; Guenther, A. B.; Monson, R. K.

    2010-12-01

    Some studies have shown soils can contribute significantly to the canopy level fluxes of volatile organic compounds (VOCs) in some ecosystem types during some seasons. Yet patterns of soil VOCs fluxes as well as controls are poorly known and so the potential importance of soil VOCs emissions on the total global BVOCs emissions from terrestrial sources remains unclear. We measured soil terpene emission at a high-elevation, mixed conifer, subalpine forest site at the Niwot Ridge Ameriflux Site in Colorado. Given the important role of terpenes on the formation of secondary organic aerosols and given that high amounts of terpenes are produced and stored in coniferous tissues (e. g. roots and litter) we focused only on these compounds in this study. The objectives were to quantify soil terpene flux and its contribution to the canopy level flux and to identify environmental variables controlling soil terpene emissions in this forest, such as tree species, tree species density, total soil organic matter content, soil temperature and soil moisture . During the summer 2009 (August), soil terpene emission rates were measured in soil chambers regularly distributed in a 200 x 200 m area around the flux tower. To test the effect of the tree species on soil emissions, additional chambers were placed on relative pure stands of each one of the representative species. The average total monoterterpene emission rate during August 2009 was 21 μg C m-2 h-1. These emissions represent 9% of the total terpene canopy fluxes reported in this forest during the same period on previous summers (August 2007, 238 μg C m-2 h-1). The range of monoterpene emission was found to be high; emissions went up to 368 μg C m-2 h-1 under specific conditions. Total sesquiterpene emissions were much lower than monoterpenes (0.04 ± 0.01 μg C m-2 h-1). Due to the high variability found, no clear effect of the space distribution was identified. However, soil terpene emissions were significantly affected by

  6. MEDICINAL USES OF ADANSONIA DIGITATA L.: AN ENDANGERED TREE SPECIES

    Directory of Open Access Journals (Sweden)

    Singh Sugandha

    2013-06-01

    Full Text Available Adansonia digitata L. belongs to the Bombacaceae family and is generally known as the African Baobab. It is called “Kalpvriksha” in India and has mythological significance in India and elsewhere. The tree already faces a crisis of survival and is listed as an endangered species in the Red Data Book. It is a massive, deciduous tree up to 25 m in height and may live for hundreds of years. It is considered to be the queen of all carbon storage trees as it absorbs huge quantities of carbon dioxide from the atmosphere. Currently the tree is suffering from drought and desertification and fear has been expressed about its regeneration. It is also reported that baobab seeds have very hard seed coats and germination rate is usually less than 20%. There is lack of awareness by the local population on the need to plant, protect and manage this endangered tree species. Several parts of the tree are reported to have interesting antioxidant and anti-inflammatory properties and are used for healing purposes. For the conservation of such a multipurpose tree species, tissue culture studies are found to be the most lucrative and promising alternative as recently some tissue culture reports are coming up. The conservation strategy under Indian subtropical states will help in studying its medicinal properties for further research. To explore its other pharmacological uses and isolation of bioactive components of this species, cell and suspension culture technology will be the most promising in near future.

  7. Genetic improvement of forest tree species

    Directory of Open Access Journals (Sweden)

    Teotônio Francisco Assis

    2011-01-01

    Full Text Available Brazilian forestry sector is considered one of the most developed in the world, being the base for important industrialsegments which use wood as raw material. Tree breeding has played an important role on improving the competitiveness ofBrazilian forestry-based companies, especially for its positive reflexes on increasing adaptation, forestry productivity and woodquality. In spite of the importance of other forest trees for the economy, such as Schizolobium, Araucaria, Populus and Hevea, themain genera under genetic improvement in the country are Eucalyptus, Pinus, Acacia and Tectona. They are used by industries likepulp and paper, siderurgy, tannin, chips for exportation and lumber, constituting an important source of revenues for the Brazilian’seconomy, besides their positive social and environmental impacts. This paper presents a generic approach to genetic improvementaspects of these four major genera currently undergoing breeding in Brazil.

  8. Schima superba outperforms other tree species by changing foliar chemical composition and shortening construction payback time when facilitated by shrubs.

    Science.gov (United States)

    Liu, Nan; Guo, Qinfeng; Ren, Hai; Sun, Zhongyu

    2016-01-01

    A 3.5-year field experiment was conducted in a subtropical degraded shrubland to assess how a nurse plant, the native shrub Rhodomyrtus tomentosa, affects the growth of the target trees Pinus elliottii, Schima superba, Castanopsis fissa, and Michelia macclurei, and to probe the intrinsic mechanisms from leaf chemical composition, construction cost (CC), and payback time aspects. We compared tree seedlings grown nearby shrub canopy (canopy subplots, CS) and in open space (open subplots, OS). S. superba in CS showed greater growth, while P. elliottii and M. macclurei were lower when compared to the plants grown in the OS. The reduced levels of high-cost compounds (proteins) and increased levels of low-cost compounds (organic acids) caused reduced CC values for P. elliottii growing in CS. While, the levels of both low-cost minerals and high-cost proteins increased in CS such that CC values of S. superba were similar in OS and CS. Based on maximum photosynthetic rates, P. elliottii required a longer payback time to construct required carbon in canopy than in OS, but the opposite was true for S. superba. The information from this study can be used to evaluate the potential of different tree species in the reforestation of subtropical degraded shrublands. PMID:26814426

  9. Slope variation and population structure of tree species from different ecological groups in South Brazil

    Directory of Open Access Journals (Sweden)

    Edmilson Bianchini

    2010-09-01

    Full Text Available Size structure and spatial arrangement of 13 abundant tree species were determined in a riparian forest fragment inParaná State, South Brazil (23"16'S and 51"01'W. The studied species were Aspidosperma polyneuron Müll. Arg., Astronium graveolens Jacq. and Gallesia integrifolia (Spreng Harms (emergent species; Alseis floribunda Schott, Ruprechtia laxiflora Meisn. and Bougainvillea spectabilis Willd. (shade-intolerant canopy species; Machaerium paraguariense Hassl, Myroxylum peruiferum L. and Chrysophyllum gonocarpum (Mart. & Eichler ex Miq. Engl. (shade-tolerant canopy species; Sorocea bonplandii (Baill. Bürger, Trichilia casaretti C. Dc, Trichilia catigua A. Juss. and Actinostemon concolor (Spreng. Müll. Arg. (understory small trees species. Height and diameter structures and basal area of species were analyzed. Spatial patterns and slope correlation were analyzed by Moran's / spatial autocorrelation coefficient and partial Mantel test, respectively. The emergent and small understory species showed the highest and the lowest variations in height, diameter and basal area. Size distribution differed among emergent species and also among canopy shade-intolerant species. The spatial pattern ranged among species in all groups, except in understory small tree species. The slope was correlated with spatial pattern for A. polyneuron, A. graveolens, A. floribunda, R. laxiflora, M. peruiferum and T. casaretti. The results indicated that most species occurredin specific places, suggesting that niche differentiation can be an important factor in structuring the tree community.Visando contribuir para o conhecimento das estratégias devida de espécies em fragmentos florestais, foram determinadas as estruturas de tamanho e espacial de 13 espécies arbóreas do remanescente de floresta ciliar no Estado do Paraná, no Sul do Brasil (23"16'S e 51"01'W. Foram analisadas as espécies: Aspidosperma polyneuron Müll. Arg., Astronium graveolens Jacq. e Gallesia

  10. Effects of location within the tree canopy on carbohydrates, organic acids, amino acids and phenolic compounds in the fruit peel and flesh from three apple (Malus × domestica) cultivars.

    Science.gov (United States)

    Feng, Fengjuan; Li, Mingjun; Ma, Fengwang; Cheng, Lailiang

    2014-01-01

    Fruits from three cultivars of apple (Malus × domestica Borkh.)-'McIntosh', 'Gala' and 'Mutsu'-were harvested from the exterior and interior of the tree canopy. Peel and flesh tissues were sampled separately to determine how the position of the fruit on the tree might affect the levels of the primary and secondary metabolites in the fruit. Fruit from the outer-canopy had a higher fresh weight and a higher soluble solids content compared with inner-canopy fruit. Both the flesh and peel of the outer-canopy fruit had higher concentrations of soluble sugars and sugar alcohols, but lower starch concentrations than the inner-canopy fruit. Canopy position did not significantly affect malic acid concentrations, except in the peel of 'McIntosh' and the flesh of 'Mutsu'. Although levels of ascorbic and succinic acids were higher in the peel of the outer-canopy fruit, the responses of other organic acids to canopy position depended on tissue type and cultivar. Except for histidine, lysine, threonine and glycine, most amino acids accumulated at higher concentrations in the inner-canopy fruit. By contrast, levels of phenolic compounds from both the peel and flesh were significantly higher in the outer-canopy fruit. The significant effects of location within the canopy on both primary metabolites and secondary metabolites demonstrate the importance of light exposure on apple fruit quality. PMID:26504536

  11. Influence of tree species on the herbaceous understory and soil chemical characteristics in a silvopastoral system in semi-arid northeastern Brazil

    Directory of Open Access Journals (Sweden)

    R. S. C. Menezes

    1999-12-01

    Full Text Available Studies from some semi-arid regions of the world have shown the beneficial effect of trees in silvopastoral systems, by promoting the formation of resource islands and increasing the sustainability of the system. No data are available in this respect for tree species of common occurrence in semi-arid Northeastern Brazil. In the present study, conducted in the summer of 1996, three tree species (Zyziphus joazeiro, Spondias tuberosa and Prosopis juliflora: found within Cenchrus ciliaris pastures were selected to evaluate differences on herbaceous understory and soil chemical characteristics between samples taken under the tree canopy and in open grass areas. Transects extending from the tree trunk to open grass areas were established, and soil (0-15 cm and herbaceous understory (standing live biomass in 1 m² plots samples were taken at 0, 25, 50, 100, 150 and 200% of the average canopy radius (average radius was 6.6 ± 0.5, 4.5 ± 0.5, and 5.3 ± 0.8 m for Z. joazeiro, P. juliflora, and S. tuberosa , respectively. Higher levels of soil C, N, P, Ca, Mg, K, and Na were found under the canopies of Z. joazeiro and P. juliflora: trees, as compared to open grass areas. Only soil Mg organic P were higher under the canopies of S. tuberosa trees, as compared to open grass areas. Herbaceous understory biomass was significantly lower under the canopy of S. tuberosa and P. juliflora trees (107 and 96 g m-2, respectively relatively to open grass areas (145 and 194 g m-2. No herbaceous biomass differences were found between Z. joazeiro canopies and open grass areas (107 and 87 g m-2, respectively. Among the three tree species studied, Z. joazeiro was the one that presented the greatest potential for use in a silvopastoral system at the study site, since it had a larger nutrient stock in the soil without negatively affecting herbaceous understory biomass, relatively to open grass areas.

  12. Tree Species Classification By Multiseasonal High Resolution Satellite Data

    Science.gov (United States)

    Elatawneh, Alata; Wallner, Adelheid; Straub, Christoph; Schneider, Thomas; Knoke, Thomas

    2013-12-01

    Accurate forest tree species mapping is a fundamental issue for sustainable forest management and planning. Forest tree species mapping with the means of remote sensing data is still a topic to be investigated. The Bavaria state institute of forestry is investigating the potential of using digital aerial images for forest management purposes. However, using aerial images is still cost- and time-consuming, in addition to their acquisition restrictions. The new space-born sensor generations such as, RapidEye, with a very high temporal resolution, offering multiseasonal data have the potential to improve the forest tree species mapping. In this study, we investigated the potential of multiseasonal RapidEye data for mapping tree species in a Mid European forest in Southern Germany. The RapidEye data of level A3 were collected on ten different dates in the years 2009, 2010 and 2011. For data analysis, a model was developed, which combines the Spectral Angle Mapper technique with a 10-fold- cross-validation. The analysis succeeded to differentiate four tree species; Norway spruce (Picea abies L.), Silver Fir (Abies alba Mill.), European beech (Fagus sylvatica) and Maple (Acer pseudoplatanus). The model success was evaluated using digital aerial images acquired in the year 2009 and inventory point records from 2008/09 inventory. Model results of the multiseasonal RapidEye data analysis achieved an overall accuracy of 76%. However, the success of the model was evaluated only for all the identified species and not for the individual.

  13. Variación florística de especies arbóreas a escala local en un bosque de tierra firme en la Amazonia colombiana Floristic variation of canopy tree species at a local scale on tierra firme forests in colombian Amazonia

    Directory of Open Access Journals (Sweden)

    Juan Sebastian Barreto Silva

    2010-03-01

    Full Text Available El presente estudio se llevó a cabo en cinco hectáreas de una parcela permanente establecida en el Parque Nacional Amacayacu, Amazonia colombiana. En éste, se evaluó el efecto de la variación ambiental y la configuración espacial sobre los patrones florísticos de las especies arbóreas (DAP>10 cm a escala local en un bosque de tierra firme. Se estudió la variación florística y ambiental en cuadrantes de 20x20 m. Adicionalmente, se consideraron diferentes categorías de abundancia (total, alta, media y baja. Se utilizó el Análisis de Correspondencia Linealizado y el Análisis de Correspondencia Canónica, seguido de una partición de la variación, para cuantificar la magnitud a la cual el ambiente y la limitación en dispersión determinan la variación florística. La fracción espacial, representando procesos de autocorrelación como la limitación en dispersión, se analizó mediante dos métodos: Asumiendo un polinomio de tercer grado y por el método de Coordenadas Principales de Matrices Vecinas (PCNM. La diversidad beta de la parcela fue baja. El PCNM aparece como el método de análisis más apropiado para estudios a esta escala. Las diferencias florísticas explicadas a lo largo de la parcela de 5-ha fueron principalmente asociadas con procesos biológicos como la limitación en dispersión. La mayor parte de la variación florística, no obstante, no fue explicada por las variables ambientales o espaciales consideradas. En conclusión, estos resultados sugieren que procesos aleatorios son determinantes esenciales de la variación espacial de las especies arbóreas a escala local en tierra firme en los bosques en el Parque Nacional Amacayacu.This study was carried out in a 5-ha permanent plot established in the Amacayacu National Park, Colombian Amazonia. We assessed the extent at which floristic patterns of tree species were determined by either the environmental variation or the spatial configuration in tierra firme

  14. Impact of tree leaf phenology on growth rates and reproduction in the spring flowering species Trillium erectum (Liliaceae).

    Science.gov (United States)

    Routhier, Marie-Claude; Lapointe, Line

    2002-03-01

    We investigated the impact of overstory tree leaf phenology on growth rates, carbon allocation pattern, and fruit characteristics in the spring flowering species, Trillium erectum (Liliaceae). Air temperature, overstory canopy closure, and T. erectum phenology were monitored at three locations following a latitudinal gradient in Québec, Canada. Northern sugar maple trees leaf out at cooler temperatures than more southern populations, while Trillium development was initiated at the same soil temperature irrespective of the latitude. Therefore, in northern areas, the time between initiation of T. erectum leaf expansion and canopy closure was shorter than in southern areas, which left less time for northern plants to accumulate reserves before canopy closure. Differences in growth patterns were noted between T. erectum populations. From a south-north gradient, investment to reproduction, total plant biomass, and annual growth rate decreased, while specific leaf area and stem height increased, indicating shade acclimation. The length of the high light period in early spring seems to be a determinant for spring flowering plants' growth and reproduction and may explain the northern distribution limit of some of these species. PMID:21665648

  15. Geographical range and local abundance of tree species in China.

    Directory of Open Access Journals (Sweden)

    Haibao Ren

    Full Text Available Most studies on the geographical distribution of species have utilized a few well-known taxa in Europe and North America, with little research in China and its wide range of climate and forest types. We assembled large datasets to quantify the geographic ranges of tree species in China and to test several biogeographic hypotheses: 1 whether locally abundant species tend to be geographically widespread; 2 whether species are more abundant towards their range-centers; and 3 how abundances are correlated between sites. Local abundances of 651 species were derived from four tree plots of 20-25 ha where all individuals ≥1 cm in stem diameter were mapped and identified taxonomically. Range sizes of these species across China were then estimated from over 460,000 geo-referenced records; a Bayesian approach was used, allowing careful measures of error of each range estimate. The log-transformed range sizes had a bell-shaped distribution with a median of 703,000 km(2, and >90% of 651 species had ranges >10(5 km(2. There was no relationship between local abundance and range size, and no evidence for species being more abundant towards their range-centers. Finally, species' abundances were positively correlated between sites. The widespread nature of most tree species in China suggests few are vulnerable to global extinction, and there is no indication of the double-peril that would result if rare species also had narrow ranges.

  16. Fuelwood quality of promising tree species for alkaline soil sites in relation to tree age

    Energy Technology Data Exchange (ETDEWEB)

    Goel, V.L.; Behl, H.M. [National Botanical Research Inst., Lucknow (India). Biomass Research Center

    1996-06-01

    The fuelwood quality of five tree species suitable for afforestation of alkaline soil sites was investigated in relation to tree age for establishing harvest rotation cycles. Prosopis juliflora and Acacia nilotica were found to be the most suitable species for short rotation fuel wood forestry programmes because of their high wood density, biomass yield, low ash and moisture content, and good heat of combustion at the juvenile stage. The performance of other species like Acacia auriculiformis, Terminalia arjuna and Sesbania formosa is discussed. (author)

  17. Germplasm characterization of three jabuticaba tree species

    Directory of Open Access Journals (Sweden)

    Moeses Andrigo Danner

    2011-09-01

    Full Text Available The purpose of this study was to characterize cultivated genotypes of three jabuticaba species (Plinia cauliflora, P. trunciflora, and P. jaboticaba. Phenology and fruit growth, as well as leaf, flower and fruit traits were evaluated. Variability in all traits was observed among genotypes of the three jabuticaba species. The trait peduncle size is indicated for differentiation of the three species under study. The leaf and fruit sizes of the genotypes P. trunciflora 3, P. trunciflora 4, P. trunciflora 5 and P. jaboticaba 1 differ from those described in the literature for these species, indicating the formation of ecotypes. Jabuticaba fruit skin contains high anthocyanin and flavonoid concentrations, with potential use in food and pharmaceutical industries.

  18. Thermal acclimation of leaf respiration of tropical trees and lianas: response to experimental canopy warming, and consequences for tropical forest carbon balance.

    Science.gov (United States)

    Slot, Martijn; Rey-Sánchez, Camilo; Gerber, Stefan; Lichstein, Jeremy W; Winter, Klaus; Kitajima, Kaoru

    2014-09-01

    Climate warming is expected to increase respiration rates of tropical forest trees and lianas, which may negatively affect the carbon balance of tropical forests. Thermal acclimation could mitigate the expected respiration increase, but the thermal acclimation potential of tropical forests remains largely unknown. In a tropical forest in Panama, we experimentally increased nighttime temperatures of upper canopy leaves of three tree and two liana species by on average 3 °C for 1 week, and quantified temperature responses of leaf dark respiration. Respiration at 25 °C (R25 ) decreased with increasing leaf temperature, but acclimation did not result in perfect homeostasis of respiration across temperatures. In contrast, Q10 of treatment and control leaves exhibited similarly high values (range 2.5-3.0) without evidence of acclimation. The decrease in R25 was not caused by respiratory substrate depletion, as warming did not reduce leaf carbohydrate concentration. To evaluate the wider implications of our experimental results, we simulated the carbon cycle of tropical latitudes (24°S-24°N) from 2000 to 2100 using a dynamic global vegetation model (LM3VN) modified to account for acclimation. Acclimation reduced the degree to which respiration increases with climate warming in the model relative to a no-acclimation scenario, leading to 21% greater increase in net primary productivity and 18% greater increase in biomass carbon storage over the 21st century. We conclude that leaf respiration of tropical forest plants can acclimate to nighttime warming, thereby reducing the magnitude of the positive feedback between climate change and the carbon cycle.

  19. Geographical Range and Local Abundance of Tree Species in China

    Science.gov (United States)

    Ren, Haibao; Condit, Richard; Chen, Bin; Mi, Xiangcheng; Cao, Min; Ye, Wanhui; Hao, Zhanqing; Ma, Keping

    2013-01-01

    Most studies on the geographical distribution of species have utilized a few well-known taxa in Europe and North America, with little research in China and its wide range of climate and forest types. We assembled large datasets to quantify the geographic ranges of tree species in China and to test several biogeographic hypotheses: 1) whether locally abundant species tend to be geographically widespread; 2) whether species are more abundant towards their range-centers; and 3) how abundances are correlated between sites. Local abundances of 651 species were derived from four tree plots of 20–25 ha where all individuals ≥1 cm in stem diameter were mapped and identified taxonomically. Range sizes of these species across China were then estimated from over 460,000 geo-referenced records; a Bayesian approach was used, allowing careful measures of error of each range estimate. The log-transformed range sizes had a bell-shaped distribution with a median of 703,000 km2, and >90% of 651 species had ranges >105 km2. There was no relationship between local abundance and range size, and no evidence for species being more abundant towards their range-centers. Finally, species’ abundances were positively correlated between sites. The widespread nature of most tree species in China suggests few are vulnerable to global extinction, and there is no indication of the double-peril that would result if rare species also had narrow ranges. PMID:24130772

  20. Species tree estimation and the historical biogeography of heroine cichlids.

    Science.gov (United States)

    Hulsey, C Darrin; Keck, Benjamin P; Hollingsworth, Phillip R

    2011-01-01

    Heroine cichlids are major components of the fish faunas in both Central America and the Caribbean. To examine the evolutionary patterns of how cichlids colonized both of these regions, we reconstructed the phylogenetic relationships among 23 cichlid lineages. We used three phylogenetically novel nuclear markers (Dystropin b, Myomesin1, and Wnt7b) in combination with sequence data from seven other gene regions (Nd2, Rag1, Enc1, Sreb2, Ptr, Plagl2, and Zic1) to elucidate the species tree of these cichlids. The species examined represent major heroine lineages in South America, Central America, and the Greater Antilles. The individual gene trees of these groups were topologically quite discordant. Therefore, we combined the genetic partitions and inferred the species tree using both concatenation and a coalescent-based Bayesian method. The two resulting phylogenetic topologies were largely concordant but differed in two fundamental ways. First, more nodes in the concatenated tree were supported with substantial or 100% Bayesian posterior support than in the coalescent-based tree. Second, there was a minor, but biogeographically critical, topological difference between the concatenated and coalescent-based trees. Nevertheless, both analyses recovered topologies consistent with the Greater Antillean heroines being phylogenetically nested within the largely Central American heroine radiation. This study suggests that reconstructions of cichlid phylogeny and historical biogeography should account for the vagaries of individual gene histories.

  1. Impact of tree species on silicon cycling in temperate soil-tree systems

    OpenAIRE

    Cornelis, Jean-Thomas

    2010-01-01

    The distribution and origin of silicon (Si) in the soil-tree system has not been thoroughly researched, despite the crucial role of the terrestrial Si cycle in major biogeochemical processes due to its close linkage with other cycles (i.e. N, P and C). The PhD thesis focuses on Si cycling in temperate forest ecosystems to investigate the effect of tree species on Si distribution in soil-tree systems and the relative role of biogenic and litho/pedogenic Si pools in the release of dissolved ...

  2. A Pine Is a Pine and a Spruce Is a Spruce--The Effect of Tree Species and Stand Age on Epiphytic Lichen Communities.

    Science.gov (United States)

    Bäcklund, Sofia; Jönsson, Mari; Strengbom, Joachim; Frisch, Andreas; Thor, Göran

    2016-01-01

    With an increasing demand for forest-based products, there is a growing interest in introducing fast-growing non-native tree species in forest management. Such introductions often have unknown consequences for native forest biodiversity. In this study, we examine epiphytic lichen species richness and species composition on the trunks of non-native Pinus contorta and compare these to the native Pinus sylvestris and Picea abies in managed boreal forests in northern Sweden across a chronosequence of age classes. Overall, we recorded a total of 66,209 lichen occurrences belonging to 57 species in the 96 studied forest stands. We found no difference in species richness of lichens between stands of P. contorta and P. sylvestris, but stands of P. abies had higher total species richness. However, species richness of lichens in stands of P. abies decreased with increasing stand age, while no such age effect was detected for P. contorta and P. sylvestris. Lichen species composition progressively diverged with increasing stand age, and in 30-year-old stands all three tree species showed species-specific assemblages. Epiphytic lichen assemblages in stands of 30-year-old P. contorta were influenced by greater basal area, canopy closure, and average diameter at breast height, P. abies stands by higher branch density and canopy closure, and stands of P. sylvestris by greater bark crevice depth. Differences in lichen species richness and composition were mainly explained by canopy closure and habitat availability, and the greater canopy closure in mature P. abies stands promoted the colonization and growth of calicioid lichen species. Our results indicate that the non-native P. contorta have similar species richness as the native P. sylvestris. The main difference in lichen species richness and composition is between P. abies and Pinus spp. in managed forests of boreal Sweden. PMID:26799558

  3. A Pine Is a Pine and a Spruce Is a Spruce--The Effect of Tree Species and Stand Age on Epiphytic Lichen Communities.

    Directory of Open Access Journals (Sweden)

    Sofia Bäcklund

    Full Text Available With an increasing demand for forest-based products, there is a growing interest in introducing fast-growing non-native tree species in forest management. Such introductions often have unknown consequences for native forest biodiversity. In this study, we examine epiphytic lichen species richness and species composition on the trunks of non-native Pinus contorta and compare these to the native Pinus sylvestris and Picea abies in managed boreal forests in northern Sweden across a chronosequence of age classes. Overall, we recorded a total of 66,209 lichen occurrences belonging to 57 species in the 96 studied forest stands. We found no difference in species richness of lichens between stands of P. contorta and P. sylvestris, but stands of P. abies had higher total species richness. However, species richness of lichens in stands of P. abies decreased with increasing stand age, while no such age effect was detected for P. contorta and P. sylvestris. Lichen species composition progressively diverged with increasing stand age, and in 30-year-old stands all three tree species showed species-specific assemblages. Epiphytic lichen assemblages in stands of 30-year-old P. contorta were influenced by greater basal area, canopy closure, and average diameter at breast height, P. abies stands by higher branch density and canopy closure, and stands of P. sylvestris by greater bark crevice depth. Differences in lichen species richness and composition were mainly explained by canopy closure and habitat availability, and the greater canopy closure in mature P. abies stands promoted the colonization and growth of calicioid lichen species. Our results indicate that the non-native P. contorta have similar species richness as the native P. sylvestris. The main difference in lichen species richness and composition is between P. abies and Pinus spp. in managed forests of boreal Sweden.

  4. Is tree species diversity or tree species identity the most important driver of European forest soil carbon stocks?

    Science.gov (United States)

    Vesterdal, Lars; Muhie Dawud, Seid; Raulund-Rasmussen, Karsten; Finér, Leena; Domisch, Timo

    2016-04-01

    Land management includes the selection of specific tree species and tree species mixtures for European forests. Studies of functional species diversity effects have reported positive effects for aboveground carbon (C) sequestration, but the question remains whether higher soil C stocks could also result from belowground niche differentiation including more efficient root exploitation of soils. We studied topsoil C stocks in tree species diversity gradients established within the FunDivEurope project to explore biodiversity-ecosystem functioning relationships in six European forest types in Finland, Poland, Germany, Romania, Spain and Italy. In the Polish forest type we extended the sampling to also include subsoils. We found consistent but modest effects of species diversity on total soil C stocks (forest floor and 0-20 cm) across the six European forest types. Carbon stocks in the forest floor alone and in the combined forest floor and mineral soil layers increased with increasing tree species diversity. In contrast, there was a strong effect of species identity (broadleaf vs. conifer) and its interaction with site-related factors. Within the Polish forest type we sampled soils down to 40 cm and found that species identity was again the main factor explaining total soil C stock. However, species diversity increased soil C stocks in deeper soil layers (20-40 cm), while species identity influenced C stocks significantly within forest floors and the 0-10 cm layer. Root biomass increased with diversity in 30-40 cm depth, and a positive relationship between C stocks and root biomass in the 30-40 cm layer suggested that belowground niche complementarity could be a driving mechanism for higher root carbon input and in turn a deeper distribution of C in diverse forests. We conclude that total C stocks are mainly driven by tree species identity. However, modest positive diversity effects were detected at the European scale, and stronger positive effects on subsoil C stocks

  5. Influence of tree canopy on N{sub 2} fixation by pasture legumes and soil rhizobial abundance in Mediterranean oak woodlands

    Energy Technology Data Exchange (ETDEWEB)

    Carranca, C., E-mail: corina.carranca@iniav.pt [INIAV, Qta Marquês, 2784-505 Oeiras (Portugal); Castro, I.V.; Figueiredo, N. [INIAV, Qta Marquês, 2784-505 Oeiras (Portugal); Redondo, R. [Laboratorio de Isotopos Estables, Universidade Autonoma, Madrid (Spain); Rodrigues, A.R.F. [Centro de Estudos Florestais, ISA/UL, Tapada Ajuda, 1349-017 Lisboa (Portugal); Saraiva, I.; Maricato, R. [INIAV, Qta Marquês, 2784-505 Oeiras (Portugal); Madeira, M.A.V. [Centro de Estudos Florestais, ISA/UL, Tapada Ajuda, 1349-017 Lisboa (Portugal)

    2015-02-15

    Symbiotic N{sub 2} fixation is of primordial significance in sustainable agro-forestry management as it allows reducing the use of mineral N in the production of mixed stands and by protecting the soils from degradation. Thereby, on a 2-year basis, N{sub 2} fixation was evaluated in four oak woodlands under Mediterranean conditions using a split-plot design and three replicates. {sup 15}N technique was used for determination of N{sub 2} fixation rate. Variations in environmental conditions (temperature, rainfall, radiation) by the cork tree canopy as well as the age of stands and pasture management can cause great differences in vegetation growth, legume N{sub 2} fixation, and soil rhizobial abundance. In the present study, non-legumes dominated the swards, in particular beneath the tree canopy, and legumes represented only 42% of total herbage. A 2-fold biomass reduction was observed in the oldest sown pasture in relation to the medium-age sward (6 t DW ha{sup −1} yr{sup −1}). Overall, competition of pasture growth for light was negligible, but soil rhizobial abundance and symbiotic N{sub 2} fixation capacity were highly favored by this environmental factor in the spring and outside the influence of tree canopy. Nitrogen derived from the atmosphere was moderate to high (54–72%) in unsown and sown swards. Inputs of fixed N2 increased from winter to spring due to more favorable climatic conditions (temperature and light intensity) for both rhizobia and vegetation growths. Assuming a constant fixation rate at each seasonal period, N{sub 2} fixation capacity increased from about 0.10 kg N ha{sup −1} per day in the autumn–winter period to 0.15 kg N ha{sup −1} per day in spring. Belowground plant material contributed to 11% of accumulated N in pasture legumes and was not affected by canopy. Size of soil fixing bacteria contributed little to explain pasture legumes N. - Highlights: • Legumes fixation in oak woodlands was quantified in terms of biomass and N

  6. Where to nest? Ecological determinants of chimpanzee nest abundance and distribution at the habitat and tree species scale.

    Science.gov (United States)

    Carvalho, Joana S; Meyer, Christoph F J; Vicente, Luis; Marques, Tiago A

    2015-02-01

    Conversion of forests to anthropogenic land-uses increasingly subjects chimpanzee populations to habitat changes and concomitant alterations in the plant resources available to them for nesting and feeding. Based on nest count surveys conducted during the dry season, we investigated nest tree species selection and the effect of vegetation attributes on nest abundance of the western chimpanzee, Pan troglodytes verus, at Lagoas de Cufada Natural Park (LCNP), Guinea-Bissau, a forest-savannah mosaic widely disturbed by humans. Further, we assessed patterns of nest height distribution to determine support for the anti-predator hypothesis. A zero-altered generalized linear mixed model showed that nest abundance was negatively related to floristic diversity (exponential form of the Shannon index) and positively with the availability of smaller-sized trees, reflecting characteristics of dense-canopy forest. A positive correlation between nest abundance and floristic richness (number of plant species) and composition indicated that species-rich open habitats are also important in nest site selection. Restricting this analysis to feeding trees, nest abundance was again positively associated with the availability of smaller-sized trees, further supporting the preference for nesting in food tree species from dense forest. Nest tree species selection was non-random, and oil palms were used at a much lower proportion (10%) than previously reported from other study sites in forest-savannah mosaics. While this study suggests that human disturbance may underlie the exclusive arboreal nesting at LCNP, better quantitative data are needed to determine to what extent the construction of elevated nests is in fact a response to predators able to climb trees. Given the importance of LCNP as refuge for Pan t. verus our findings can improve conservation decisions for the management of this important umbrella species as well as its remaining suitable habitats. PMID:25224379

  7. Fine scale spatial genetic structure in Pouteria reticulata (Engl. Eyma (Sapotaceae, a dioecious, vertebrate dispersed tropical rain forest tree species

    Directory of Open Access Journals (Sweden)

    John W. Schroeder

    2014-08-01

    Full Text Available Dioecious tropical tree species often have small flowers and fleshy fruits indicative of small-insect pollination and vertebrate seed dispersal. We hypothesize that seed mediated gene flow should be exceed pollen-mediated gene flow in such species, leading to weak patterns of fine scale spatial genetic structure (SGS. In the present study, we characterize novel microsatellite DNA markers and test for SGS in sapling (N=100 and adult trees (N=99 of the dioecious canopy tree Pouteria reticulata (Sapotaceae in a 50 ha forest dynamics plot on Barro Colorado Island (BCI, Panama. The five genetic markers contained between five and 15 alleles per locus, totaling 51 alleles in the sample population. Significant SGS at local spatial scales (<100m was detected in the sapling (dbh≈1cm and adult (dbh≥20cm size classes, but was stronger in the former (sapling Sp=0.010±0.004, adult Sp=0.006±0.002, suggesting demographic thinning. The degree of SGS was lower than the value expected for non-vertebrate dispersed tropical trees (Sp=0.029, but similar to the average value for vertebrate dispersed tropical trees (Sp=0.009 affirming the dispersal potential of vertebrate dispersed tropical trees in faunally intact forests.

  8. Effects of tree species composition on within-forest distribution of understorey species

    NARCIS (Netherlands)

    Oijen, van D.; Feijen, M.; Hommel, P.W.F.M.; Ouden, den J.; Waal, de R.W.

    2005-01-01

    Question: Do tree species, with different litter qualities, affect the within-forest distribution of forest understorey species on intermediate to base-rich soils? Since habitat loss and fragmentation have caused ancient forest species to decline, those species are the main focus of this study. Loca

  9. Multilocus inference of species trees and DNA barcoding.

    Science.gov (United States)

    Mallo, Diego; Posada, David

    2016-09-01

    The unprecedented amount of data resulting from next-generation sequencing has opened a new era in phylogenetic estimation. Although large datasets should, in theory, increase phylogenetic resolution, massive, multilocus datasets have uncovered a great deal of phylogenetic incongruence among different genomic regions, due both to stochastic error and to the action of different evolutionary process such as incomplete lineage sorting, gene duplication and loss and horizontal gene transfer. This incongruence violates one of the fundamental assumptions of the DNA barcoding approach, which assumes that gene history and species history are identical. In this review, we explain some of the most important challenges we will have to face to reconstruct the history of species, and the advantages and disadvantages of different strategies for the phylogenetic analysis of multilocus data. In particular, we describe the evolutionary events that can generate species tree-gene tree discordance, compare the most popular methods for species tree reconstruction, highlight the challenges we need to face when using them and discuss their potential utility in barcoding. Current barcoding methods sacrifice a great amount of statistical power by only considering one locus, and a transition to multilocus barcodes would not only improve current barcoding methods, but also facilitate an eventual transition to species-tree-based barcoding strategies, which could better accommodate scenarios where the barcode gap is too small or inexistent.This article is part of the themed issue 'From DNA barcodes to biomes'. PMID:27481787

  10. Remote Sensing of Almond and Walnut Tree Canopy Temperatures Using an Inexpensive Infrared Sensor on a Small Unmanned Aerial Vehicle

    Science.gov (United States)

    Crawford, Kellen Ethan

    Improving water use efficiency in agriculture will become increasingly important in the face of decreasing water resources and a growing population. Increasing water use efficiency, or water productivity, has been shown to greatly reduce irrigation water usage in many orchard crops with little to no impact on yield. In some specialty crops, improving water productivity can even lead to a higher value crop. Current irrigation practices depend largely on uniform applications of water over large fields with varying degrees of heterogeneity. As a result, much of the field receives more water than it needs. A system to monitor the needs of each plant or smaller groups of plants within the field would be helpful in distributing irrigation water according to each plant or group of plants' needs. Such a system would help conserve water resources. Stomatal conductance is a good indicator of plant water-based stress, as it is the main response a plant has to limit transpiration-related water losses. The difference between leaf temperature and air temperature, when adjusted for environmental conditions, can give a good indication of stomatal conductance. Recent efforts at UC Davis have employed a handheld sensor suite to measure leaf temperature and other environmental variables like wind speed, air temperature, and humidity in almond and walnut trees. Though effective, this method requires walking or driving through the orchard and measuring several leaves on a given tree, so it is impractical for large-scale monitoring. Satellite and aircraft can measure canopy temperatures remotely, but these applications typically do not have the spatial resolution for precise monitoring or the temporal resolution necessary for irrigation decisions, and they are too expensive and impractical for smaller-scale farms. A smaller unmanned aerial vehicle (UAV) could employ the same methods as satellite and larger aircraft-based systems, but relatively inexpensively and at a scale catered to

  11. Interactions between terrestrial mammals and the fruits of two neotropical rainforest tree species

    Science.gov (United States)

    Camargo-Sanabria, Angela A.; Mendoza, Eduardo

    2016-05-01

    Mammalian frugivory is a distinctive biotic interaction of tropical forests; however, most efforts in the Neotropics have focused on cases of animals foraging in the forest canopy, in particular primates and bats. In contrast much less is known about this interaction when it involves fruits deposited on the forest floor and terrestrial mammals. We conducted a camera-trapping survey to analyze the characteristics of the mammalian ensembles visiting fruits of Licania platypus and Pouteria sapota deposited on the forest floor in a well preserved tropical rainforest of Mexico. Both tree species produce large fruits but contrast in their population densities and fruit chemical composition. In particular, we expected that more species of terrestrial mammals would consume P. sapota fruits due to its higher pulp:seed ratio, lower availability and greater carbohydrate content. We monitored fruits at the base of 13 trees (P. sapota, n = 4 and L. platypus, n = 9) using camera-traps. We recorded 13 mammal species from which we had evidence of 8 consuming or removing fruits. These eight species accounted for 70% of the species of mammalian frugivores active in the forest floor of our study area. The ensemble of frugivores associated with L. platypus (6 spp.) was a subset of that associated with P. sapota (8 spp). Large body-sized species such as Tapirus bairdii, Pecari tajacu and Cuniculus paca were the mammals more frequently interacting with fruits of the focal species. Our results further our understanding of the characteristics of the interaction between terrestrial mammalian frugivores and large-sized fruits, helping to gain a more balanced view of its importance across different tropical forests and providing a baseline to compare against defaunated forests.

  12. Gene trees versus species trees: reassessing life-history evolution in a freshwater fish radiation.

    Science.gov (United States)

    Waters, Jonathan M; Rowe, Diane L; Burridge, Christopher P; Wallis, Graham P

    2010-10-01

    Mechanisms of speciation are best understood in the context of phylogenetic relationships and as such have often been inferred from single gene trees, typically those derived from mitochondrial DNA (mtDNA) markers. Recent studies, however, have noted the potential for phylogenetic discordance between gene trees and underlying species trees (e.g., due to stochastic lineage sorting, introgression, or selection). Here, we employ a variety of nuclear DNA loci to reassess evolutionary relationships within a recent freshwater fish radiation to reappraise modes of speciation. New Zealand's freshwater-limited Galaxias vulgaris complex is thought to have evolved from G. brevipinnis, a widespread migratory species that retains a plesiomorphic marine juvenile phase. A well-resolved tree, based on four mtDNA regions, previously suggested that marine migratory ability has been lost on 3 independent occasions in the evolution of this species flock (assuming that loss of diadromy is irreversible). Here, we use pseudogene (galaxiid Numt: 1801 bp), intron (S: 903 bp), and exon (RAG-1: 1427 bp) markers, together with mtDNA, to reevaluate this hypothesis of parallel evolution. Interestingly, partitioned Bayesian analysis of concatenated nuclear sequences (3141 bp) and concatenated nuclear and mtDNA (4770 bp) both recover phylogenies implying a single loss of diadromy, not three parallel losses as previously inferred from mtDNA alone. This phylogenetic result is reinforced by a multilocus analysis performed using Bayesian estimation of species trees (BEST) software that estimates the posterior distribution of species trees under a coalescent model. We discuss factors that might explain the apparently misleading phylogenetic inferences generated by mtDNA. PMID:20603441

  13. Effects of location within the tree canopy on carbohydrates, organic acids, amino acids and phenolic compounds in the fruit peel and flesh from three apple (Malus × domestica) cultivars

    OpenAIRE

    Fengjuan Feng; Mingjun Li; Fengwang Ma; Lailiang Cheng

    2014-01-01

    Fruits from three cultivars of apple (Malus × domestica Borkh.)—‘McIntosh’, ‘Gala’ and ‘Mutsu’—were harvested from the exterior and interior of the tree canopy. Peel and flesh tissues were sampled separately to determine how the position of the fruit on the tree might affect the levels of the primary and secondary metabolites in the fruit. Fruit from the outer-canopy had a higher fresh weight and a higher soluble solids content compared with inner-canopy fruit. Both the flesh and peel of the ...

  14. tropiTree: an NGS-based EST-SSR resource for 24 tropical tree species.

    Science.gov (United States)

    Russell, Joanne R; Hedley, Peter E; Cardle, Linda; Dancey, Siobhan; Morris, Jenny; Booth, Allan; Odee, David; Mwaura, Lucy; Omondi, William; Angaine, Peter; Machua, Joseph; Muchugi, Alice; Milne, Iain; Kindt, Roeland; Jamnadass, Ramni; Dawson, Ian K

    2014-01-01

    The development of genetic tools for non-model organisms has been hampered by cost, but advances in next-generation sequencing (NGS) have created new opportunities. In ecological research, this raises the prospect for developing molecular markers to simultaneously study important genetic processes such as gene flow in multiple non-model plant species within complex natural and anthropogenic landscapes. Here, we report the use of bar-coded multiplexed paired-end Illumina NGS for the de novo development of expressed sequence tag-derived simple sequence repeat (EST-SSR) markers at low cost for a range of 24 tree species. Each chosen tree species is important in complex tropical agroforestry systems where little is currently known about many genetic processes. An average of more than 5,000 EST-SSRs was identified for each of the 24 sequenced species, whereas prior to analysis 20 of the species had fewer than 100 nucleotide sequence citations. To make results available to potential users in a suitable format, we have developed an open-access, interactive online database, tropiTree (http://bioinf.hutton.ac.uk/tropiTree), which has a range of visualisation and search facilities, and which is a model for the efficient presentation and application of NGS data.

  15. Nitrogen addition enhances drought sensitivity of young deciduous tree species

    Directory of Open Access Journals (Sweden)

    Christoph Dziedek

    2016-07-01

    Full Text Available Understanding how trees respond to global change drivers is central to predict changes in forest structure and functions. Although there is evidence on the mode of nitrogen (N and drought (D effects on tree growth, our understanding of the interplay of these factors is still limited. Simultaneously, as mixtures are expected to be less sensitive to global change as compared to monocultures, we aimed to investigate the combined effects of N addition and D on the productivity of three tree species (Fagus sylvatica, Quercus petraea, Pseudotsuga menziesii in relation to functional diverse species mixtures using data from a four-year field experiment in Northwest Germany. Here we show that species mixing can mitigate the negative effects of combined N fertilization and D events, but the community response is mainly driven by the combination of certain traits rather than the tree species richness of a community. For beech, we found that negative effects of D on growth rates were amplified by N fertilization (i.e. combined treatment effects were non-additive, while for oak and fir, the simultaneous effects of N and D were additive. Beech and oak were identified as most sensitive to combined N+D effects with a strong size-dependency observed for beech, suggesting that the negative impact of N+D becomes stronger with time as beech grows larger. As a consequence, the net biodiversity effect declined at the community level, which can be mainly assigned to a distinct loss of complementarity in beech-oak mixtures. This pattern, however, was not evident in the other species-mixtures, indicating that neighborhood composition (i.e. trait combination, but not tree species richness mediated the relationship between tree diversity and treatment effects on tree growth. Our findings point to the importance of the qualitative role (‘trait portfolio’ that biodiversity play in determining resistance of diverse tree communities to environmental changes. As such, they

  16. Nitrogen Addition Enhances Drought Sensitivity of Young Deciduous Tree Species.

    Science.gov (United States)

    Dziedek, Christoph; Härdtle, Werner; von Oheimb, Goddert; Fichtner, Andreas

    2016-01-01

    Understanding how trees respond to global change drivers is central to predict changes in forest structure and functions. Although there is evidence on the mode of nitrogen (N) and drought (D) effects on tree growth, our understanding of the interplay of these factors is still limited. Simultaneously, as mixtures are expected to be less sensitive to global change as compared to monocultures, we aimed to investigate the combined effects of N addition and D on the productivity of three tree species (Fagus sylvatica, Quercus petraea, Pseudotsuga menziesii) in relation to functional diverse species mixtures using data from a 4-year field experiment in Northwest Germany. Here we show that species mixing can mitigate the negative effects of combined N fertilization and D events, but the community response is mainly driven by the combination of certain traits rather than the tree species richness of a community. For beech, we found that negative effects of D on growth rates were amplified by N fertilization (i.e., combined treatment effects were non-additive), while for oak and fir, the simultaneous effects of N and D were additive. Beech and oak were identified as most sensitive to combined N+D effects with a strong size-dependency observed for beech, suggesting that the negative impact of N+D becomes stronger with time as beech grows larger. As a consequence, the net biodiversity effect declined at the community level, which can be mainly assigned to a distinct loss of complementarity in beech-oak mixtures. This pattern, however, was not evident in the other species-mixtures, indicating that neighborhood composition (i.e., trait combination), but not tree species richness mediated the relationship between tree diversity and treatment effects on tree growth. Our findings point to the importance of the qualitative role ('trait portfolio') that biodiversity play in determining resistance of diverse tree communities to environmental changes. As such, they provide further

  17. Early positive effects of tree species richness on herbivory in a large-scale forest biodiversity experiment influence tree growth

    OpenAIRE

    Schuldt, Andreas; Bruelheide,Helge; Härdtle, Werner; Assmann, Thorsten; Ying LI; Ma, Keping; von Oheimb, Goddert; Zhang, Jiayong

    2015-01-01

    Despite the importance of herbivory for the structure and functioning of species-rich forests, little is known about how herbivory is affected by tree species richness, and more specifically by random vs. non-random species loss. We assessed herbivore damage and its effects on tree growth in the early stage of a large-scale forest biodiversity experiment in subtropical China that features random and non-random extinction scenarios of tree mixtures numbering between one and 24 species. In cont...

  18. Biomass models to estimate carbon stocks for hardwood tree species

    Energy Technology Data Exchange (ETDEWEB)

    Ruiz-Peinado, R.; Montero, G.; Rio, M. del

    2012-11-01

    To estimate forest carbon pools from forest inventories it is necessary to have biomass models or biomass expansion factors. In this study, tree biomass models were developed for the main hardwood forest species in Spain: Alnus glutinosa, Castanea sativa, Ceratonia siliqua, Eucalyptus globulus, Fagus sylvatica, Fraxinus angustifolia, Olea europaea var. sylvestris, Populus x euramericana, Quercus canariensis, Quercus faginea, Quercus ilex, Quercus pyrenaica and Quercus suber. Different tree biomass components were considered: stem with bark, branches of different sizes, above and belowground biomass. For each species, a system of equations was fitted using seemingly unrelated regression, fulfilling the additivity property between biomass components. Diameter and total height were explored as independent variables. All models included tree diameter whereas for the majority of species, total height was only considered in the stem biomass models and in some of the branch models. The comparison of the new biomass models with previous models fitted separately for each tree component indicated an improvement in the accuracy of the models. A mean reduction of 20% in the root mean square error and a mean increase in the model efficiency of 7% in comparison with recently published models. So, the fitted models allow estimating more accurately the biomass stock in hardwood species from the Spanish National Forest Inventory data. (Author) 45 refs.

  19. Tolerance of Four Tropical Tree Species to Heavy Petroleum Contamination

    NARCIS (Netherlands)

    Perez-Hernandez, I.; Ochoa-Gaona, S.; Schroeder, R.H.A.; Rivera-Cruz, M.C.; Geissen, V.

    2013-01-01

    Four species of trees were selected to evaluate the tolerance to heavy crude oil contamination by means of a tolerance index integrating germination, height, biomass and survival as variables. Fresh seeds to Cedrela odorata (tropical cedar), Haematoxylum campechianum (tinto bush), Swietenia macrophy

  20. Initial growth of six forest tree species in differents spacing conditions

    Directory of Open Access Journals (Sweden)

    Daniel Ferreira do Nascimento

    2012-03-01

    Full Text Available This work veriflied the influence of planting spacing on the initial growth of six forest species, at the age of 22 months, in plantations of forest recomposition in the Guandu River Basin. The experiment was installed in the SFE - thermoelectric power plants Barbosa Lima Sobrinho, located in the City of Seropédica-RJ. Forty eight tree species were planted, using the spacings, 1.0 x 1.0, 1.5 x 1.5, 2.0 and 2.0 x 3.0 x 2.0 m, which are the study treatments. At 22 months after planting, it was evaluated the growth in height, diameter at ground level (DNS and area of the canopy for the species, Anadenanthera macrocarpa Benth. Brenan (angico vermelho, Schinus terebinthifolius Raddi (aroeira pimenteira, Schizolobium parahyba Blake (guapuruvu Chorisia speciosa St. Hill (paineira, Cordia sp. (babosa branca and Inga marginata (ingá. It was found that the studied species behaved in a different way in the differents spacing of planting, and that the planting density significantly influenced on the initial growth of all the species. In general, in wider planting spacings, the plants had higher growth.

  1. Floral biology, flowering phenology and floral visitors of five insect-pollinated tree species in a tropical lowland rainforest remnant of Pernambuco, Brazil

    OpenAIRE

    Krause, Leonhard

    2008-01-01

    Reproductive processes of frequent canopy tree species that persisted up to now in the few remnants of the Brazilian Atlantic forest might be thought to be robust. To test this hypothesis, the reproductive biology, flowering phenology, and the floral visitors of Tapirira guinanensis (Anacardiaceae), Ocotea glomerata (Lauraceae), Trichilia lepidota (Meliaceae), Sclerolobium densiflorum (Fabaceae), and Eschweilera ovata (Lecythidaceae) were studied in a 319 ha forest fragment 30 km north of Rec...

  2. Biomass Equations for Tropical Forest Tree Species in Mozambique

    Directory of Open Access Journals (Sweden)

    Rosta Mate

    2014-03-01

    Full Text Available Chanfuta (Afzelia quanzensis Welw., Jambire (Millettia stuhlmannii Taub. and Umbila (Pterocarpus angolensis D.C. are, among others, three of the main tropical tree species producing commercial timber in Mozambique. The present study employed destructive biomass estimation methods at three localities in Mozambique (Inhaminga, Mavume, and Tome to acquire data on the mean diameter at breast height (DBH, and height of trees sampled in 21 stands each of Chanfuta and Jambire, and 15 stands of Umbila. Mean diameter at breast height (DBH (ob for Chanfuta, Jambire, and Umbila was: 33.8 ± 12.6 (range 13.5–61.1, 33.4 ± 7.4 (range 21.0–52.2, and 27.0 ± 9.5 (range 14.0–46.5 cm. The mean total values for biomass (kg of trees of Chanfuta, Jambire, and Umbila trees were 864, 1016, and 321 respectively. The mean percentages of total tree biomass as stem, branch and leaf respectively were 54, 43, and 3 for Chanfuta; 77, 22, and 1 for Jambire; and 46, 51, and 3 for Umbila. The best fit species-specific equation for estimating total above ground biomass (AGB was the power equation with only DBH considered as independent variable yielding coefficient of determination (R2 ranging from 0.89 to 0.97. At stand level, a total mean of 27.3 tons ha−1 biomass was determined of which studied species represented 94.6%. At plot level, total mean biomass for Jambire was 11.8 tons ha−1, Chanfuta and Umbila 9.9 and 4.1 tons ha−1 respectively. The developed power equation fitted total and stem biomass data well and could be used for biomass prediction of the studied species in Mozambique.

  3. Attributes for MRB_E2RF1 Catchments by Major River Basins in the Conterminous United States: NLCD 2001 Tree Canopy

    Science.gov (United States)

    Wieczorek, Michael E.; LaMotte, Andrew E.

    2010-01-01

    This tabular data set represents the mean percent tree canopy from the Canopy Layer of the National Land Cover Dataset 2001 (LaMotte and Wieczorek, 2010), compiled for every MRB_E2RF1 catchment of Major River Basins (MRBs, Crawford and others, 2006). The source data set represents tree canopy percentage for the conterminous United States for 2001. The Canopy Layer of the National Land Cover Data Set for 2001 was produced through a cooperative project conducted by the Multi-Resolution Land Characteristics (MRLC) Consortium. The MRLC Consortium is a partnership of Federal agencies (http://www.mrlc.gov), consisting of the U.S. Geological Survey (USGS), the National Oceanic and Atmospheric Administration (NOAA), the U.S. Environmental Protection Agency (USEPA), the U.S. Department of Agriculture (USDA), the U.S. Forest Service (USFS), the National Park Service (NPS), the U.S. Fish and Wildlife Service (USFWS), the Bureau of Land Management (BLM), and the USDA Natural Resources Conservation Service (NRCS). The MRB_E2RF1 catchments are based on a modified version of the U.S. Environmental Protection Agency's (USEPA) ERF1_2 and include enhancements to support national and regional-scale surface-water quality modeling (Nolan and others, 2002; Brakebill and others, 2011). Data were compiled for every MRB_E2RF1 catchment for the conterminous United States covering New England and Mid-Atlantic (MRB1), South Atlantic-Gulf and Tennessee (MRB2), the Great Lakes, Ohio, Upper Mississippi, and Souris-Red-Rainy (MRB3), the Missouri (MRB4), the Lower Mississippi, Arkansas-White-Red, and Texas-Gulf (MRB5), the Rio Grande, Colorado, and the Great basin (MRB6), the Pacific Northwest (MRB7) river basins, and California (MRB8).

  4. Widespread Discordance of Gene Trees with Species Tree inDrosophila: Evidence for Incomplete Lineage Sorting

    Energy Technology Data Exchange (ETDEWEB)

    Pollard, Daniel A.; Iyer, Venky N.; Moses, Alan M.; Eisen,Michael B.

    2006-08-28

    The phylogenetic relationship of the now fully sequencedspecies Drosophila erecta and D. yakuba with respect to the D.melanogaster species complex has been a subject of controversy. All threepossible groupings of the species have been reported in the past, thoughrecent multi-gene studies suggest that D. erecta and D. yakuba are sisterspecies. Using the whole genomes of each of these species as well as thefour other fully sequenced species in the subgenus Sophophora, we set outto investigate the placement of D. erecta and D. yakuba in the D.melanogaster species group and to understand the cause of the pastincongruence. Though we find that the phylogeny grouping D. erecta and D.yakuba together is the best supported, we also find widespreadincongruence in nucleotide and amino acid substitutions, insertions anddeletions, and gene trees. The time inferred to span the two keyspeciation events is short enough that under the coalescent model, theincongruence could be the result of incomplete lineage sorting.Consistent with the lineage-sorting hypothesis, substitutions supportingthe same tree were spatially clustered. Support for the different treeswas found to be linked to recombination such that adjacent genes supportthe same tree most often in regions of low recombination andsubstitutions supporting the same tree are most enriched roughly on thesame scale as linkage disequilibrium, also consistent with lineagesorting. The incongruence was found to be statistically significant androbust to model and species choice. No systematic biases were found. Weconclude that phylogenetic incongruence in the D. melanogaster speciescomplex is the result, at least in part, of incomplete lineage sorting.Incomplete lineage sorting will likely cause phylogenetic incongruence inmany comparative genomics datasets. Methods to infer the correct speciestree, the history of every base in the genome, and comparative methodsthat control for and/or utilize this information will be

  5. Effects of Tree Canopy Structure and Understory Vegetation on the Effectiveness of Open-Top-Chamber in Manipulating Boreal Forest Microclimate

    Science.gov (United States)

    Teuber, L. M.; Nilsson, M. C.; Wardle, D.; Dorrepaal, E.

    2014-12-01

    Open-top chambers (OTCs) are widely used to passively increase soil and air temperature in various open habitats, such as alpine and arctic tundra, and temperate grasslands. Several studies report warming effects of 1-2 °C in arctic and alpine tundra, and up to 6 °C in temperate grasslands. The variation between studies can be mostly attributed to differences in the abiotic environment, such as snow cover and solar irradiance. Vegetation height and openness affects the amount of irradiance that reaches the ground and may therefore indirectly impact the effectiveness of OTCs. The use of OTCs in forested ecosystems might therefore be limited by reduced canopy openness, while their effect on changes in soil temperature and soil moisture content might additionally be affected by the understory vegetation type and cover. Nevertheless, OTC's are an immensely useful tool in climate-change studies, and could benefit research in forest ecosystems. In this study we therefore investigated whether OTCs can be used to manipulate microclimate in the northern boreal forest and how tree canopy cover and understory vegetation influence OTC effects on air and soil temperature and on soil moisture content.We compared OTC effects at ten sites that were situated along a fire chronosequence in the northern boreal forest in Sweden. Sites were dominated by Pinus sylvestris and Picea abies, and time since the last fire ranged from 47-367 years, resulting in varying degrees of tree canopy openness. We applied full factorial combinations of OTC warming and dwarf shrub removal and moss removal at each site. We measured canopy cover using hemispherical photography; air and soil temperature as well as soil moisture were measured hourly from June until September. Preliminary analyses indicate that OTCs increased monthly mean air temperatures by up to 0.9 °C across all treatments and forest stands. However, the degree of warming showed clear relations with the presence or absence of the

  6. A multigene species tree for Western Mediterranean painted frogs (Discoglossus).

    Science.gov (United States)

    Pabijan, Maciej; Crottini, Angelica; Reckwell, Dennis; Irisarri, Iker; Hauswaldt, J Susanne; Vences, Miguel

    2012-09-01

    Painted frogs (Discoglossus) are an anuran clade that originated in the Upper Miocene. Extant species are morphologically similar and have a circum-Mediterranean distribution. We assembled a multilocus dataset from seven nuclear and four mitochondrial genes for several individuals of all but one of the extant species and reconstructed a robust phylogeny by applying a coalescent-based species-tree method and a concatenation approach, both of which gave congruent results. The earliest phylogenetic split within Discoglossus separates D. montalentii from a clade comprising all other species. Discoglossus montalentii is monophyletic for haplotype variation at all loci and has distinct morphological, bioacoustic and karyotypic characters. We find moderate support for a sister-group relationship between the Iberian taxa and the Moroccan D. scovazzi, and high support for a D. pictus -D. sardus clade distributed around the Tyrrhenian basin. Topological discordance among gene trees during the speciation of D. galganoi, D. scovazzi, D. pictus and D. sardus is interpreted as the consequence of nearly simultaneous, vicariant diversification. The timing of these events is unclear, but possibly coincided with the final geotectonic rearrangement of the Western Mediterranean in the Middle Miocene or later during the Messinian salinity crisis. The Iberian taxa D. galganoi galganoi and D. g. jeanneae are reciprocally monophyletic in mitochondrial DNA but not in nuclear gene trees, and are therefore treated as subspecies of D. galganoi. PMID:22641173

  7. Diversification rates and species richness across the Tree of Life.

    Science.gov (United States)

    Scholl, Joshua P; Wiens, John J

    2016-09-14

    Species richness varies dramatically among clades across the Tree of Life, by over a million-fold in some cases (e.g. placozoans versus arthropods). Two major explanations for differences in richness among clades are the clade-age hypothesis (i.e. species-rich clades are older) and the diversification-rate hypothesis (i.e. species-rich clades diversify more rapidly, where diversification rate is the net balance of speciation and extinction over time). Here, we examine patterns of variation in diversification rates across the Tree of Life. We address how rates vary across higher taxa, whether rates within higher taxa are related to the subclades within them, and how diversification rates of clades are related to their species richness. We find substantial variation in diversification rates, with rates in plants nearly twice as high as in animals, and rates in some eukaryotes approximately 10-fold faster than prokaryotes. Rates for each kingdom-level clade are then significantly related to the subclades within them. Although caution is needed when interpreting relationships between diversification rates and richness, a positive relationship between the two is not inevitable. We find that variation in diversification rates seems to explain most variation in richness among clades across the Tree of Life, in contrast to the conclusions of previous studies. PMID:27605507

  8. Diversification rates and species richness across the Tree of Life.

    Science.gov (United States)

    Scholl, Joshua P; Wiens, John J

    2016-09-14

    Species richness varies dramatically among clades across the Tree of Life, by over a million-fold in some cases (e.g. placozoans versus arthropods). Two major explanations for differences in richness among clades are the clade-age hypothesis (i.e. species-rich clades are older) and the diversification-rate hypothesis (i.e. species-rich clades diversify more rapidly, where diversification rate is the net balance of speciation and extinction over time). Here, we examine patterns of variation in diversification rates across the Tree of Life. We address how rates vary across higher taxa, whether rates within higher taxa are related to the subclades within them, and how diversification rates of clades are related to their species richness. We find substantial variation in diversification rates, with rates in plants nearly twice as high as in animals, and rates in some eukaryotes approximately 10-fold faster than prokaryotes. Rates for each kingdom-level clade are then significantly related to the subclades within them. Although caution is needed when interpreting relationships between diversification rates and richness, a positive relationship between the two is not inevitable. We find that variation in diversification rates seems to explain most variation in richness among clades across the Tree of Life, in contrast to the conclusions of previous studies.

  9. TREE SPECIES COMMUNITY SPATIAL PARTITION IN FUNCTION OF SOIL DRAINAGE IN AN ARAUCARIA FOREST FRAGMENT IN SOUTHERN BRAZIL

    Directory of Open Access Journals (Sweden)

    Pedro Higuchi

    2014-06-01

    Full Text Available http://dx.doi.org/10.5902/1980509814580The relationship vegetation-soil can contribute to understand the forest structure, supporting biodiversity conservation. Thus, the aim of the present study was to verify the existence of spatial partition of the tree species community in an Araucaria forest fragment in function of soil drainage. For this sake, an environmental characterization (soil drainage, physical and chemical soil properties, topography, compression of soil, depth of soil and canopy cover was realized in 25 plots of 20 x 20m, where tree individuals, with circumference at breast height ≥15.7 cm were previously counted, measured and identified. The data were analysed by Mann-Withney test, non-parametric multivariate ANOVA (NPMANOVA, multivariate analysis (NMDS and indicator species analysis. In this small spatial scale there were two drainage classes, corresponding to well and moderately-drained soils, with environmental differences that determined the richness, the spatial partition of the tree community and the occurrence of indicator species. Thus, we conclude that in the study forest fragment soil drainage spatial variations were determinant in the floristic-structural heterogeneity observed in tree community. 

  10. Mapping the geographic distribution of canopy species communities in lowland Amazon rainforest with CAO-AToMS (Invited)

    Science.gov (United States)

    Feret, J.; Asner, G. P.

    2013-12-01

    Mapping regional canopy diversity will greatly advance our understanding as well as the conservation of tropical rainforests. Changes in species composition across space and time are particularly important to understand the influence of climate, human activity and environmental factors on these ecosystems, but to date such monitoring is extremely challenging and is facing a scale gap between small-scale, highly detailed field studies and large-scale, low-resolution satellite observations. Advances were recently made in the field of spectroscopic imagery for the estimation of canopy alpha-diversity, and an original approach based on the segmentation of the spectral space proved its ability to estimate Shannon diversity index with unprecedented accuracy. We adapted this method in order to estimate spectral dissimilarity across landscape as a proxy for changes in species composition. We applied this approach and mapped species composition over four sites located in lowland rainforest of Peruvian Amazon. This study was based on spectroscopic imagery acquired using the Carnegie Airborne Observatory (CAO) Airborne Taxonomic Mapping System (AToMS), operating a unique sensor combining the fine spectral and spatial resolution required for such task. We obtained accurate estimation of Bray-Curtis distance between pairs of plots, which is the most commonly used metric to estimate dissimilarity in species composition (n=497 pairs, r=0.63). The maps of species composition were then compared to topo-hydrographic properties. Our results indicated a strong shift in species composition and community diversity between floodplain and terra firme terrain conditions as well as a significantly higher diversity of species communities within Amazonian floodplains. These results pave the way for global mapping of tropical canopy diversity at fine geographic resolution.

  11. Litter Fall and Its Decomposition in Sapium sebiferum Roxb.: An Invasive Tree Species in Western Himalaya

    Directory of Open Access Journals (Sweden)

    Vikrant Jaryan

    2014-01-01

    Full Text Available Recognizing that high litter fall and its rapid decomposition are key traits of invasive species, litter fall and its decay in Sapium sebiferum Roxb. were studied in Palampur. For this, litter traps of dimension 50 × 50 × 50 cm3 were placed in under-canopy and canopy gap of the species. Litter fall was monitored monthly and segregated into different components. For litter decay studies, litter bags of dimension 25 × 20 cm2 with a mesh size 2 mm were used and the same were analyzed on a fortnightly basis. Litter fall in both under-canopy and canopy gap was highest in November (1.16 Mg ha−1 y−1 in under-canopy and 0.38 Mg ha−1 y−1 in canopy gap and lowest during March. Litter production in under-canopy and canopy gap was 4.04 Mg ha−1 y−1 and 1.87 Mg ha−1 y−1, respectively. These values are comparable to sal forest (1.7 t C ha−1 y−1, chir pine-mixed forest (2.1 t C ha−1 y−1, and mixed oak-conifer forest (2.8 t C ha−1 y−1 of the Western Himalaya. The decay rate, 0.46% day−1 in under-canopy and 0.48% day−1 in canopy gap, was also fast. Owing to this the species may be able to modify the habitats to its advantage, as has been reported elsewhere.

  12. Firewood properties of some Indian mountain tree and shrub species

    Energy Technology Data Exchange (ETDEWEB)

    Bhatt, B.P.; Tomar, J.M.S. [ICAR Research Complex for NEH Region, Agroforestry Div., Meghalaya (India)

    2002-10-01

    Quantitative analysis of 26 indigenous mountain fuelwood species of North-Eastern Himalayan region was carried out to identify trees with potential for fuelwood production. A fuelwood value index (FYI) was defined as calorific value x density/ash content. Betula nitida, Machilus bombycina, Itea macrophylla, Cryptomeria japonica, Gmelina arborea, Simingtonia populnea, Macaranga denticulata and Schima wallichii were shown to have promising firewood production. (Author)

  13. Community organization of tree species along soil gradients in a north-eastern USA forest

    NARCIS (Netherlands)

    Bigalow, S.W.; Canham, C.D.

    2002-01-01

    1 A study was carried out in oak-northern hardwood forest in NW Connecticut USA involving measurements of growth, light and soil environment of saplings of six canopy trees that are strongly associated with particular soil types as adults. The objectives were to determine patterns of growth response

  14. Methodology to evaluate the insecticide potential of forest tree species

    International Nuclear Information System (INIS)

    The flora diversity of Colombia has an enormous potential in the rational use of its forest resources. Trees with biocidal effects to control pests and diseases need to be investigated. The objective of this research was to develop a methodology with low costs, easy application and quick results. The methodology employed was as follows: selection of tree species based on bibliography, ancestral reports and personal observations. The process was as follows: field collection of plants, preparation of plants extracts and test with Artemia salina Leach to detect biological activity of the extracts using LC50. Bioassays with those extract more promising (LC50 less than 1000 ppm) Determination of active compounds. The methodology was employed with 5 forest tree species: guarea guidonia (L) Sleumer and trichia hirta L. (Meliaceae), Machaerium Moritzianum Benth. (Fabaceae), Swinglea glutinosa Merrill (rutaceae) and Mammea americana L. (Clusiaceae). Using Artemia salina Leach as indicator of biocidal potential, two species were selected as the most promising, those were: Swinglea glutinosa Merril and Machaerium moritzianum Benth. In addition bioassays were made to evaluate fagoinhibition on Atta cephalotes (L.) (Hym: Formicidae) and control of Alconeura. This methodology is recommended for this kind of research

  15. Fuelwood characteristics of selected indigenous tree species from central India

    Energy Technology Data Exchange (ETDEWEB)

    Jain, R.K.; Singh, B. [National Botanical Research Institute, Lucknow (India)

    1999-06-01

    Thirty tree species indigenously growing in their natural habitat in subtropical forest of central India were collected and fuelwood properties viz, moisture, silica, ash, density, carbon, nitrogen, volatile matter, calorific value and fuel value index (FVI) calculated to screen desirable species for potential production of fuelwood in these areas. The present study revealed that Acer oblongum, Betula alonoides, Grevillea robusta, Limonia acidissima, Lyonia ovalifolia, Madhuca indica, Melia azedarch, Morinda tinctoria, Myrica sapida, Prunus cornuta, Pyrus pashia, Quercus langinosa, Rhamnus triqueter and Stereospermum xylocarpum possess excellent fuelwood qualities. (Author)

  16. Mapping Species Composition of Forests and Tree Plantations in Northeastern Costa Rica with an Integration of Hyperspectral and Multitemporal Landsat Imagery

    Science.gov (United States)

    Fagan, Matthew E.; Defries, Ruth S.; Sesnie, Steven E.; Arroyo-Mora, J. Pablo; Soto, Carlomagno; Singh, Aditya; Townsend, Philip A.; Chazdon, Robin L.

    2015-01-01

    An efficient means to map tree plantations is needed to detect tropical land use change and evaluate reforestation projects. To analyze recent tree plantation expansion in northeastern Costa Rica, we examined the potential of combining moderate-resolution hyperspectral imagery (2005 HyMap mosaic) with multitemporal, multispectral data (Landsat) to accurately classify (1) general forest types and (2) tree plantations by species composition. Following a linear discriminant analysis to reduce data dimensionality, we compared four Random Forest classification models: hyperspectral data (HD) alone; HD plus interannual spectral metrics; HD plus a multitemporal forest regrowth classification; and all three models combined. The fourth, combined model achieved overall accuracy of 88.5%. Adding multitemporal data significantly improved classification accuracy (p less than 0.0001) of all forest types, although the effect on tree plantation accuracy was modest. The hyperspectral data alone classified six species of tree plantations with 75% to 93% producer's accuracy; adding multitemporal spectral data increased accuracy only for two species with dense canopies. Non-native tree species had higher classification accuracy overall and made up the majority of tree plantations in this landscape. Our results indicate that combining occasionally acquired hyperspectral data with widely available multitemporal satellite imagery enhances mapping and monitoring of reforestation in tropical landscapes.

  17. Schima superba outperforms other tree species by changing foliar chemical composition and shortening construction payback time when facilitated by shrubs

    OpenAIRE

    Nan Liu; Qinfeng Guo; Hai Ren; Zhongyu Sun

    2016-01-01

    A 3.5-year field experiment was conducted in a subtropical degraded shrubland to assess how a nurse plant, the native shrub Rhodomyrtus tomentosa, affects the growth of the target trees Pinus elliottii, Schima superba, Castanopsis fissa, and Michelia macclurei, and to probe the intrinsic mechanisms from leaf chemical composition, construction cost (CC), and payback time aspects. We compared tree seedlings grown nearby shrub canopy (canopy subplots, CS) and in open space (open subplots, OS). S...

  18. Change in hydraulic properties and leaf traits of a tall rainforest tree species subjected to long-term throughfall exclusion in the perhumid tropics

    Directory of Open Access Journals (Sweden)

    B. Schuldt

    2010-11-01

    Full Text Available In a throughfall displacement experiment on Sulawesi, Indonesia, three 0.16 ha stands of a premontane perhumid rainforest were exposed to a two-year soil desiccation period that reduced the soil moisture in the upper soil layers beyond the conventional wilting point. About 25 variables, including leaf morphological and chemical traits, stem diameter growth and hydraulic properties of the xylem in the trunk and terminal twigs, were investigated in trees of the tall-growing tree species Castanopsis acuminatissima (Fagaceae by comparing desiccated roof plots with nearby control plots. We tested the hypotheses that this tall and productive species is particularly sensitive to drought, and the exposed upper sun canopy is more affected than the shade canopy. Hydraulic conductivity in the xylem of terminal twigs normalised to vessel lumen area was reduced by 25%, leaf area-specific conductivity by 10–33% during the desiccation treatment. Surprisingly, the leaves present at the end of the drought treatment were significantly larger, but not smaller in the roof plots, though reduced in number (about 30% less leaves per unit of twig sapwood area, which points to a drought effect on the leaf bud formation while the remaining leaves may have profited from a surplus of water. Mean vessel diameter and axial conductivity in the outermost xylem of the trunk were significantly reduced and wood density increased, while annual stem diameter increment decreased by 26%. In contradiction to our hypotheses, (i we found no signs of major damage to the C. acuminatissima trees nor to any other drought sensitivity of tall trees, and (ii the exposed upper canopy was not more drought susceptible than the shade canopy.

  19. Carbon and nitrogen in forest floor and mineral soil under six common European tree species

    DEFF Research Database (Denmark)

    Vesterdal, Lars; Schmidt, Inger K.; Callesen, Ingeborg;

    2007-01-01

    The knowledge of tree species effects on soil C and N pools is scarce, particularly for European deciduous tree species. We studied forest floor and mineral soil carbon and nitrogen under six common European tree species in a common garden design replicated at six sites in Denmark. Three decades...

  20. Analyzing lead concentration in the sycamore tree species in high- and low-traffic areas of Rasht, Iran.

    Science.gov (United States)

    Hashemi, Seyed Armin; Alinejad, Farzaneh; FallahChay, Mozaffar

    2015-06-01

    Important heavy metals such as lead and cadmium are part of the pollutants produced by cars and are spread in the urban environment by traffic flow. In order to study the amount of contamination in the trees along the streets and to determine the traffic parameters that affect the lead content in sycamore leaves in Rasht, four stations on the margins of the city streets were selected for this case study in terms of traffic volume (low or high). Traffic parameters including three high-traffic stations considering daily and monthly traffic volumes and one low-traffic station were selected. First, 32 sycamore bases were randomly chosen at the intervals of 10-15 m from the whole range of tree canopy in order to determine the absorption of lead; and then, 20 g of each sample were tested to determine the amount of lead absorption. The results of this study, on the amount of lead absorption by the sycamore tree species at three high-traffic and one control station, showed that Takhti station had the highest amount of lead absorption (37.19 ppm) compared with other three stations. Therefore, the sycamore tree species can be an appropriate one for the margins of urban streets.

  1. Determinations of Urban Political Ecology: The Distribution Pattern Canopy Cover of Tree and Spatial inequality in Tehran

    Directory of Open Access Journals (Sweden)

    T. Karami

    2012-01-01

    kind of social production whose imagination and change are influenced by political economy, dominant pattern of public and private ownership in society (Heynen, Perkins and Roy, 2006: 3. The aforementioned perspective clearly states that urban material conditions which includes urban environment too are controlled and manipulated by the elite and city experts to serve their interests. This issue is conducive to make some of the urban social groups marginalized and deprived from natural riches and urban environmental artifacts. As a result, the quality of urban environment (physically and socially increases in some neighborhoods and decreases in others (Heynen, Kaika and Swyngedouw, 2006: 1-15. Since unequal greenery distribution with creating imbalanced ecological conditions often plays its role in a feedback cycle on environment quality and intensification of inequalities within urban life environment, the present study uses pattern of canopy distribution located in areas of residential uses (private and public to reveal social, economic and spatial inequalities in Tehran. 3- DiscussionThe results of this research in relation to Tehran city confirm the determining position of urban political ecology in forming distribution pattern and density of trees canopy located in areas of Tehran. This is a subject which is confirmed by studies conducted on urban green space (including public and private in the cities such as San Diego, Toronto (by Perkins, Heynen and Wilson 2004, Scobedo and colleagues 2005, Heynen, Perkins and Roy 2006 and Conway, Shakeel and Atallah 2011. Also, so far many researchers on the urban issues of Tehran city (such as Madanipoor 2005, Horkad 2009 have emphasized the conformity of natural topography over social topography in Tehran. The result f this attempt, while confirming aforementioned perspectives, indicated that the distribution pattern of canopy density in residential areas(private urban green space has a greater capability to portray social

  2. Semi-supervised SVM for individual tree crown species classification

    Science.gov (United States)

    Dalponte, Michele; Ene, Liviu Theodor; Marconcini, Mattia; Gobakken, Terje; Næsset, Erik

    2015-12-01

    In this paper a novel semi-supervised SVM classifier is presented, specifically developed for tree species classification at individual tree crown (ITC) level. In ITC tree species classification, all the pixels belonging to an ITC should have the same label. This assumption is used in the learning of the proposed semi-supervised SVM classifier (ITC-S3VM). This method exploits the information contained in the unlabeled ITC samples in order to improve the classification accuracy of a standard SVM. The ITC-S3VM method can be easily implemented using freely available software libraries. The datasets used in this study include hyperspectral imagery and laser scanning data acquired over two boreal forest areas characterized by the presence of three information classes (Pine, Spruce, and Broadleaves). The experimental results quantify the effectiveness of the proposed approach, which provides classification accuracies significantly higher (from 2% to above 27%) than those obtained by the standard supervised SVM and by a state-of-the-art semi-supervised SVM (S3VM). Particularly, by reducing the number of training samples (i.e. from 100% to 25%, and from 100% to 5% for the two datasets, respectively) the proposed method still exhibits results comparable to the ones of a supervised SVM trained with the full available training set. This property of the method makes it particularly suitable for practical forest inventory applications in which collection of in situ information can be very expensive both in terms of cost and time.

  3. Tree Species and Their Space Requirements in Six Urban Environments Worldwide

    OpenAIRE

    Jens Dahlhausen; Peter Biber; Thomas Rötzer; Enno Uhl; Hans Pretzsch

    2016-01-01

    Urban trees have gained in importance during recent decades, but little is known about the temporal dynamic of tree growth in urban areas. The present study investigated the allometric relationships of stem diameter, tree height, and crown radius for six different tree species in six metropolises worldwide. Increment cores of the trees were used for identifying the relationship of basal area and basal area increment and for extrapolating the temporal dynamics for each species in relation to t...

  4. Post-breeding bird responses to canopy tree retention, stand size, and edge in regenerating Appalachian hardwood stands

    Science.gov (United States)

    McDermott, M.E.; Wood, P.B.

    2011-01-01

    Avian use of even-aged timber harvests is likely affected by stand attributes such as size, amount of edge, and retained basal area, all characteristics that can easily be manipulated in timber harvesting plans. However, few studies have examined their effects during the post-breeding period. We studied the impacts of clearcut, low-leave two-age, and high-leave two-age harvesting on post-breeding birds using transect sampling and mist-netting in north-central West Virginia. In our approach, we studied the effects of these harvest types as well as stand size and edge on species characteristic of both early-successional and mature forest habitats. In 2005-2006, 13 stands ranging from 4 to 10. years post-harvest and 4-21. ha in size were sampled from late June through mid-August. Capture rates and relative abundance were similar among treatments for generalist birds. Early-successional birds had the lowest capture rates and fewer species (~30% lower), and late-successional birds reached their highest abundance and species totals (double the other treatments) in high-leave two-age stands. Area sensitivity was evident for all breeding habitat groups. Both generalist and late-successional bird captures were negatively related to stand size, but these groups showed no clear edge effects. Mean relative abundance decreased to nearly zero for the latter group in the largest stands. In contrast, early-successional species tended to use stand interiors more often and responded positively to stand size. Capture rates for this group tripled as stand size increased from 4 to 21. ha. Few birds in the forest periphery responded to harvest edge types despite within-stand edge effects evident for several species. To create suitable habitat for early-successional birds, large, non-linear openings with a low retained basal area are ideal, while smaller harvests and increased residual tree retention would provide habitat for more late-successional birds post-breeding. Although our study

  5. Trade-offs and spatial variation of functional traits of tree species in a subtropical forest in southern Brazil

    Directory of Open Access Journals (Sweden)

    Missio FF

    2016-07-01

    Full Text Available Plant functional traits have been recognized as important factors related to the ecological strategies of species in forest ecosystems. We examined the relationships between functional traits and both tree species performance and environmental conditions in a subtropical forest in Brazil. Over four years (2008-2012, we investigated how demographic rates were related to functional traits (wood density, leaf area and tree height of 20 species sampled within 50 plots of 10 × 20 m, which had previously evaluated as to environmental conditions. Non-metric multidimensional scaling was used to order the species by their functional traits. The demographic rates were fit a posteriori to the ordination, with significant rates (p < 0.05 plotted as vectors. The relationships between environmental conditions and the community-weighted means (CWMs of trait values were verified using redundancy analysis. CWM wood density was positively correlated with soil pH. CWM leaf area and CWM maximum tree height were both negatively correlated with altitude and positively correlated with soil magnesium (Mg content. The taller species with lower wood density, which occupied the forest canopy, had a greater diameter increment and lower recruitment than did the shortest species with higher wood density. The shorter species with higher wood density, which occupied the understory, had greater recruitment and a greater increase in abundance than did the taller/lower-wood-density species. Our study (i revealed changes in the forest related to the light environment, with an increase in the relative participation of shade-tolerant species with higher wood densities, and (ii detected small-scale spatial variation in community traits as a response to variations in soil chemical properties and topography.

  6. Lianas suppress seedling growth and survival of 14 tree species in a Panamanian tropical forest.

    Science.gov (United States)

    Martínez-Izquierdo, Laura; García, María M; Powers, Jennifer S; Schnitzer, Stefan A

    2016-01-01

    Lianas are a common plant growth form in tropical forests, where they compete intensely with trees, decreasing tree recruitment, growth, and survival. If the detrimental effects of lianas vary significantly with tree species identity, as is often assumed, then lianas may influence tree species diversity and community composition. Furthermore, recent studies have shown that liana abundance and biomass are increasing relative to trees in neotropical forests, which will likely magnify the detrimental effects of lianas and may ultimately alter tree species diversity, relative abundances, and community composition. Few studies, however, have tested the responses of multiple tree species to the presence of lianas in robust, well-replicated experiments. We tested the hypotheses that lianas reduce tree seedling growth and survival, and that the effect of lianas varies with tree species identity. We used a large-scale liana removal experiment in Central Panama in which we planted 14 replicate seedlings of 14 different tree species that varied in shade tolerance in each of 16 80 x 80 m plots (eight liana-removal and eight unmanipulated controls; 3136 total seedlings). Over a nearly two-yr period, we found that tree seedlings survived 75% more, grew 300% taller, and had twice the aboveground biomass in liana-removal plots than seedlings in control plots, consistent with strong competition between lianas and tree seedlings. There were no significant differences in the response of tree species to liana competition (i.e., there was no species by treatment interaction), indicating that lianas had a similar negative effect on all 14 tree species. Furthermore, the effect of lianas did not vary with tree species shade tolerance classification, suggesting that the liana effect was not solely based on light. Based on these findings, recently observed increases in liana abundance in neotropical forests will substantially reduce tree regeneration, but will not significantly alter

  7. DNA barcoding:species delimitation in tree peonies

    Institute of Scientific and Technical Information of China (English)

    2009-01-01

    Delimitations of species are crucial for correct and precise identification of taxa.Unfortunately "spe-cies" is more a subjective than an objective concept in taxonomic practice due to difficulties in revealing patterns of infra-or inter-specific variations.Molecular phylogenetic studies at the population level solve this problem and lay a sound foundation for DNA barcoding.In this paper we exemplify the necessity of adopting a phylogenetic concept of species in DNA barcoding for tree peonies(Paeonia sect.Moutan).We used 40 samples representing all known populations of rare and endangered species and several populations of widely distributed tree peonies.All currently recognized species and major variants have been included in this study.Four chloroplast gene fragments,i.e.ndhF,rps16-trnQ,trnL-F and trnS-G(a total of 5040 characters,96 variable and 69 parsimony-informative characters) and one variable and single-copy nuclear GPAT gene fragment(2093?2197 bp,279 variable and 148 parsi-mony-informative characters) were used to construct phylogenetic relationships among the taxa.The evolutionary lineages revealed by the nuclear gene and the chloroplast genes are inconsistent with the current circumscriptions of P.decomposita,P.jishanensis,P.qiui,and P.rockii based on morphology.The inconsistencies come from(1) significant chloroplast gene divergence but little nuclear GPAT gene divergence among population systems of P.decomposita + P.rockii,and(2) well-diverged nuclear GPAT gene but little chloroplast gene divergence between P.jishanensis and P.qiui.The incongruence of the phylogenies based on the chloroplast genes and the nuclear GPAT gene is probably due to the chloro-plast capture event in evolutionary history,as no reproductive barriers exist to prevent inter-specific hybridization.We also evaluated the suitability of these genes for use as DNA barcodes for tree peonies.The variability of chloroplast genes among well-defined species or population systems of a

  8. The Impact of Missing Data on Species Tree Estimation.

    Science.gov (United States)

    Xi, Zhenxiang; Liu, Liang; Davis, Charles C

    2016-03-01

    Phylogeneticists are increasingly assembling genome-scale data sets that include hundreds of genes to resolve their focal clades. Although these data sets commonly include a moderate to high amount of missing data, there remains no consensus on their impact to species tree estimation. Here, using several simulated and empirical data sets, we assess the effects of missing data on species tree estimation under varying degrees of incomplete lineage sorting (ILS) and gene rate heterogeneity. We demonstrate that concatenation (RAxML), gene-tree-based coalescent (ASTRAL, MP-EST, and STAR), and supertree (matrix representation with parsimony [MRP]) methods perform reliably, so long as missing data are randomly distributed (by gene and/or by species) and that a sufficiently large number of genes are sampled. When data sets are indecisive sensu Sanderson et al. (2010. Phylogenomics with incomplete taxon coverage: the limits to inference. BMC Evol Biol. 10:155) and/or ILS is high, however, high amounts of missing data that are randomly distributed require exhaustive levels of gene sampling, likely exceeding most empirical studies to date. Moreover, missing data become especially problematic when they are nonrandomly distributed. We demonstrate that STAR produces inconsistent results when the amount of nonrandom missing data is high, regardless of the degree of ILS and gene rate heterogeneity. Similarly, concatenation methods using maximum likelihood can be misled by nonrandom missing data in the presence of gene rate heterogeneity, which becomes further exacerbated when combined with high ILS. In contrast, ASTRAL, MP-EST, and MRP are more robust under all of these scenarios. These results underscore the importance of understanding the influence of missing data in the phylogenomics era. PMID:26589995

  9. 图像拼接重建苹果树冠层器官三维形态%Image mosaics reconstruction of canopy organ morphology of apple trees

    Institute of Scientific and Technical Information of China (English)

    马晓丹; 孟庆宽; 张丽娇; 刘刚; 周薇

    2014-01-01

    为重建苹果树年生长期冠层器官三维形态,以休眠期、疏花期、成熟期苹果树冠层为研究对象,分别针对基于光合混合探测技术(photonicmixerdetector,PMD)的摄像机与彩色摄像机获取的强度图像与彩色图像开展冠层图像拼接技术研究。利用Scaleinvariantfeaturetransform算法的尺度不变特征,并结合Randomsampleconsensus算法精确确定图像映射模型,避免了果园非结构光及图像尺度变换的影响。以此为基础,应用拉普拉斯金字塔分解与重构算法、分层确定融合规则,实现了不同生长期的冠层图像拼接,有效克服了传统融合算法反映细节信息能力差、拼接痕迹明显等缺点。果园不同环境下(晴天顺光、晴天逆光、阴天)的试验表明:提出的拼接方法适合于苹果树年生长期的冠层器官图像拼接,且算法的鲁棒性、速度及拼接精度均能满足冠层三维重建工作的要求,研究成果对提升剪枝、疏花、测产、采摘等果园管理的信息化水平具有重要意义。%Annual growth cycle of fruit trees is the whole process of life activities with specific laws, including flower thing period and mature period. For a long time, how to construct the three-dimensional shape of an apple tree canopy with color information in different growth stages of fruit tree, has been always a research priority. At present, three methods are usually used to reconstruct 3D shape including stereo vision technology, laser scanner, and three-dimensional digitizer. The stereo vision technology is vulnerable to unstructured outdoor light. The use of a laser scanner can overcome the disadvantages above, but with slow speed to access information. The three-dimensional digitizer requires strict conditions of the external environment, and cannot obtain color information of objects. Photonic Mixer Device (PMD) is a three-dimensional imaging device based on time of flight

  10. Species selection in hardwoods research: variations in baseline physiological responses of select temperate hardwood tree species

    Institute of Scientific and Technical Information of China (English)

    Shaneka S.Lawson; Paula M.Pijut; Charles H.Michler

    2013-01-01

    Drought periods are becoming more extreme worldwide and the ability of plants to contribute towards atmospheric flux is being compromised.Properly functioning stomata provide an exit for water that has been absorbed by the roots,funneled into various cell parts,and eventually released into the atmosphere via transpiration.By observing the effects that weather conditions such as climate change may have on stomatal density,distribution,and functioning,it may be possible to elucidate a portion of the mechanisms trees use to survive longer periods of water stress.This study analyzed stomatal density (SD),stomatal conductance (gs),CO2 assimilation (A),instantaneous water-use efficiency (WUEi,and transpiration (E) rates in six native tree species in the Midwestern USA and showed that trees within the same ecotype followed similar trends,but that trees within the same family did not when exposed to identical greenhouse conditions.Naturally drought tolerant tree species demonstrated lower gs and higher WUEi,while intolerant species had higher SD.This study showed negative or no correlation between SD and gs,A,E,and WUEi and positive correlations between E and A and gs and E.

  11. Disassociating tree species associations in the eastern United States

    Directory of Open Access Journals (Sweden)

    Hanberry BB

    2014-08-01

    Full Text Available Ecologists have a long history of describing species associations including oak-hickory, one of the predominant associations in the eastern United States. But historically, oak composition did not appear particularly related to hickory composition. I assessed the relevance of the oak-hickory association and other associations using older and recent (c. 1981 and 2007 USDA Forest Service surveys. For common hickory and oak species, I determined percent composition (i.e., percent of total stems ≥12.7 cm in diameter, relative density or abundance in ecological subsections, changes in composition throughout ranges, and compared composition of oaks and hickories and other potential associations using correlation and ordination. Oaks were among the most abundant species while hickories were minor species. Hickory composition was stable while the trajectory of oak continued to decrease during the survey intervals from presettlement dominance. Rank-order correlation between oaks and hickories throughout their ranges was about the maximum as for other species (0.55 and 0.42 during the two survey periods and in the Oak-Hickory forest region, correlation between oaks and hickories was 0.04 (older surveys and 0.16 (recent surveys. Oaks were not associated with hickory in the “oak-hickory” forests of Missouri during the mid-1800s, nor were oaks associated with hickory more recently beyond correlations that occur between other eastern forest species. Oak-hickory association in particular is not an informative term for either historical open oak ecosystems or current eastern broadleaf forests. Mixed mesophytic associations, perhaps not best termed as an association, are eastern broadleaf forests where many tree species dominate forested ecosystems in the absence of filtering disturbance. Associations, even if species share similar traits, generally are not strong, stable in time, or extensive in space; differences between species result in different and

  12. Nitrogen and phosphorus additions negatively affect tree species diversity in tropical forest regrowth trajectories.

    Science.gov (United States)

    Siddique, Ilyas; Vieira, Ima Célia Guimarães; Schmidt, Susanne; Lamb, David; Carvalho, Cláudio José Reis; Figueiredo, Ricardo de Oliveira; Blomberg, Simon; Davidson, Eric A

    2010-07-01

    Nutrient enrichment is increasingly affecting many tropical ecosystems, but there is no information on how this affects tree biodiversity. To examine dynamics in vegetation structure and tree species biomass and diversity, we annually remeasured tree species before and for six years after repeated additions of nitrogen (N) and phosphorus (P) in permanent plots of abandoned pasture in Amazonia. Nitrogen and, to a lesser extent, phosphorus addition shifted growth among woody species. Nitrogen stimulated growth of two common pioneer tree species and one common tree species adaptable to both high- and low-light environments, while P stimulated growth only of the dominant pioneer tree Rollinia exsucca (Annonaceae). Overall, N or P addition reduced tree assemblage evenness and delayed tree species accrual over time, likely due to competitive monopolization of other resources by the few tree species responding to nutrient enrichment with enhanced establishment and/or growth rates. Absolute tree growth rates were elevated for two years after nutrient addition. However, nutrient-induced shifts in relative tree species growth and reduced assemblage evenness persisted for more than three years after nutrient addition, favoring two nutrient-responsive pioneers and one early-secondary tree species. Surprisingly, N + P effects on tree biomass and species diversity were consistently weaker than N-only and P-only effects, because grass biomass increased dramatically in response to N + P addition. The resulting intensified competition probably prevented an expected positive N + P synergy in the tree assemblage. Thus, N or P enrichment may favor unknown tree functional response types, reduce the diversity of coexisting species, and delay species accrual during structurally and functionally complex tropical rainforest secondary succession. PMID:20715634

  13. Two decades of historical phenology observations of African tropical tree species: exploring the past to predict the futur

    Science.gov (United States)

    Hufkens, K.; Kosmala, M.; Ewango, C.; Richardson, A. D.; Beeckman, H.

    2015-12-01

    African tropical forests cover ~630 million ha, store up to 66 Pg of carbon and represent a significant carbon sink (0.34Pg C yr-1 ). As such African tropical forests provide an important negative feedback to the global carbon cycle. Unlike temperate forests, tropical forests lack sharp temperature and photoperiod cues to constrain phenology and growth. Therefore, events such as seasonal leaf abscission and reproductive life cycles are often driven by changes in water availability. With future climate predictions expecting a warmer, and especially drier tropical Africa, it is likely we will see concomitant changes in tree growth and phenology.As tropical trees show a high degree of phenological plasticity depending on the severity of the dry season, intermittent water stress or the location of an individual in the canopy structure. As such, frequent and long term observations are key to characterize tropical tree phenology. Here I use two long term historical phenology records of weekly observations, some digitized within the context of a citizen science project (http://junglerhythms.org/), to explore differences in tree phenology between two sites (Luki and Yangambi, DR Congo) with contrasting climate regimes within the Congo basin. I describe variation in leaf, flower and fruit phenology across similar species at both locations in relation to complementary historical climatological observations. I further discuss the potential implications of changing phenology under future climate conditions as phenological changes could alter both ecosystem demography and growing season length providing important feedbacks to the climate system.

  14. Consistency and inconsistency of consensus methods for inferring species trees from gene trees in the presence of ancestral population structure.

    Science.gov (United States)

    DeGiorgio, Michael; Rosenberg, Noah A

    2016-08-01

    In the last few years, several statistically consistent consensus methods for species tree inference have been devised that are robust to the gene tree discordance caused by incomplete lineage sorting in unstructured ancestral populations. One source of gene tree discordance that has only recently been identified as a potential obstacle for phylogenetic inference is ancestral population structure. In this article, we describe a general model of ancestral population structure, and by relying on a single carefully constructed example scenario, we show that the consensus methods Democratic Vote, STEAC, STAR, R(∗) Consensus, Rooted Triple Consensus, Minimize Deep Coalescences, and Majority-Rule Consensus are statistically inconsistent under the model. We find that among the consensus methods evaluated, the only method that is statistically consistent in the presence of ancestral population structure is GLASS/Maximum Tree. We use simulations to evaluate the behavior of the various consensus methods in a model with ancestral population structure, showing that as the number of gene trees increases, estimates on the basis of GLASS/Maximum Tree approach the true species tree topology irrespective of the level of population structure, whereas estimates based on the remaining methods only approach the true species tree topology if the level of structure is low. However, through simulations using species trees both with and without ancestral population structure, we show that GLASS/Maximum Tree performs unusually poorly on gene trees inferred from alignments with little information. This practical limitation of GLASS/Maximum Tree together with the inconsistency of other methods prompts the need for both further testing of additional existing methods and development of novel methods under conditions that incorporate ancestral population structure.

  15. Consistency and inconsistency of consensus methods for inferring species trees from gene trees in the presence of ancestral population structure.

    Science.gov (United States)

    DeGiorgio, Michael; Rosenberg, Noah A

    2016-08-01

    In the last few years, several statistically consistent consensus methods for species tree inference have been devised that are robust to the gene tree discordance caused by incomplete lineage sorting in unstructured ancestral populations. One source of gene tree discordance that has only recently been identified as a potential obstacle for phylogenetic inference is ancestral population structure. In this article, we describe a general model of ancestral population structure, and by relying on a single carefully constructed example scenario, we show that the consensus methods Democratic Vote, STEAC, STAR, R(∗) Consensus, Rooted Triple Consensus, Minimize Deep Coalescences, and Majority-Rule Consensus are statistically inconsistent under the model. We find that among the consensus methods evaluated, the only method that is statistically consistent in the presence of ancestral population structure is GLASS/Maximum Tree. We use simulations to evaluate the behavior of the various consensus methods in a model with ancestral population structure, showing that as the number of gene trees increases, estimates on the basis of GLASS/Maximum Tree approach the true species tree topology irrespective of the level of population structure, whereas estimates based on the remaining methods only approach the true species tree topology if the level of structure is low. However, through simulations using species trees both with and without ancestral population structure, we show that GLASS/Maximum Tree performs unusually poorly on gene trees inferred from alignments with little information. This practical limitation of GLASS/Maximum Tree together with the inconsistency of other methods prompts the need for both further testing of additional existing methods and development of novel methods under conditions that incorporate ancestral population structure. PMID:27086043

  16. The complex biogeographic history of a widespread tropical tree species.

    Science.gov (United States)

    Dick, Christopher W; Heuertz, Myriam

    2008-11-01

    Many tropical forest tree species have broad geographic ranges, and fossil records indicate that population disjunctions in some species were established millions of years ago. Here we relate biogeographic history to patterns of population differentiation, mutational and demographic processes in the widespread rainforest tree Symphonia globulifera using ribosomal (ITS) and chloroplast DNA sequences and nuclear microsatellite (nSSR) loci. Fossil records document sweepstakes dispersal origins of Neotropical S. globulifera populations from Africa during the Miocene. Despite historical long-distance gene flow, nSSR differentiation across 13 populations from Costa Rica, Panama, Ecuador (east and west of Andes) and French Guiana was pronounced (F(ST)= 0.14, R(ST)= 0.39, P F(ST)) to the divergences between cis- and trans-Andean populations. Both DNA sequence and nSSR data reflect contrasting demographic histories in lower Mesoamerica and Amazonia. Amazon populations show weak phylogeographic structure and deviation from drift-mutation equilibrium indicating recent population expansion. In Mesoamerica, genetic drift was strong and contributed to marked differentiation among populations. The genetic structure of S. globulifera contains fingerprints of drift-dispersal processes and phylogeographic footprints of geological uplifts and sweepstakes dispersal. PMID:18764917

  17. Boron toxicity characteristics of four northern California endemic tree species

    Energy Technology Data Exchange (ETDEWEB)

    Glaubig, B.A.; Bingham, F.T.

    A greenhouse study was undertaken to determine the characteristics of soil B toxicity for four tree species endemic to The Geysers area in northern California: digger pine (Pinus sabiniana Dougl. ex D. Don), California laurel (or, California bay) (Umbellularia californica (Hoo. and Arn. Nutt.)), madrone (Arbutus menziesii Pursh), and bigleaf maple (Acer macrophyllum Pursh). Significant exponential relationships were found between soil B concentration and relative growth, and between tissue B concentration and relative growth for the four species. Significant linear relationships were found between both soil and tissue B concentration and foliar damage for the four species. Foliar damages over 25% of the leaf or needle area on digger pine, California laurel, madrone, and bigleaf maple, respectively, occurred at saturated soil extract concentrations (mmol B/L) of 1.2, 0.4, 0.5, and 0.08. Twenty-five percent foliar damage was associated with leaf or needle tissue concentrations (mmol B/kg) of 115, 100, 50, and 30 for the digger pine, California laurel, madrone, and bigleaf maple, respectively. Growth decrements of 25% occurred at saturated soil extract concentrations (mmol B/L) of 1.6, 0.3, 0.2, 0.5 for the digger pine, California laurel, madrone, and bigleaf maple, respectively. Twenty-five percent growth decrements were associated with leaf or needle tissue concentrations (mmol B/kg) of 140, 100, 20, and 7 for the digger pine, California laurel, madrone, and bigleaf maple, respectively. By comparison with two agronomic crops - cotton (Gossypium hirsutum L.) and cowpea (Vigna unguiculata L.) - the four tree species were placed into one of six B tolerance classes.

  18. 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

  19. Elevated stream inorganic nitrogen impacts on a dominant riparian tree species: Results from an experimental riparian stream system

    Science.gov (United States)

    Hultine, K. R.; Jackson, T. L.; Burtch, K. G.; Schaeffer, S. M.; Ehleringer, J. R.

    2008-12-01

    The release of inorganic nitrogen from intensive agricultural practices and urbanization has resulted in significant alterations of the aquatic nitrogen cycle in riparian ecosystems. Nevertheless, impacts of stream nitrogen inputs on the terrestrial nitrogen cycle and the water and carbon cycles are unclear. Information on terrestrial ecosystem responses to stream N loading is largely absent in part because of the difficulty in controlling for temporal and spatial variation in streamflow, geomorphology, climate, and vegetation. To address these issues, we constructed a dual-plot artificial stream riparian system within a 10-year-old plantation of a dominant riparian tree species, box elder (Acer negundo). The dual-plot design allowed for different concentrations of stream inorganic nitrogen between plots while controlling for ecohydrologic and geohydrologic variability. The system was used to investigate elevated inorganic stream nitrogen impacts on water use patterns, above-ground productivity, and leaf chemistry of streamside box elder trees over two consecutive growing seasons (2006 and 2007). One plot received inorganic soluble fertilizer that brought the NO3 concentration of stream water from 5 μmol l-1 to about 100 μmol l-1, while the second plot received no additional nitrogen. Relative stem sap flux density (Js) did not vary between plots until near the conclusion of the 2006 growing season, when trees in the fertilized plot showed a steep upswing in Js relative to trees in the control plot. Sap flux in 2007 increased consistently by 0.4% day-1 in the fertilized plot relative to the control plot over a 75-day period, before leveling off near the conclusion of the growing season. At the onset of the experiment, leaf nitrogen per unit mass and leaf nitrogen per unit area were significantly higher in the control plot, and leaf C:N ratios were lower. In 2007, however, differences in leaf chemistry disappeared, suggesting that leaf nitrogen increased in the

  20. Effects of tree species on soil properties in a forest of the northeastern United States

    OpenAIRE

    F. A. Dijkstra

    2001-01-01

    Large differences in soil pH and available Ca in the surface soil exist among tree species growing in a mixed hardwood forest in northwestern Connecticut. The observed association between tree species and specific soil chemical properties within mixed-species stands implies that changes in the distribution and abundance of tree species alter the spatial and temporal pattern of soil acidity and Ca cycling in this forest. With continuing stress of acid atmospheric deposition, these alterations ...

  1. Tree Species Traits Influence Soil Physical, Chemical, and Biological Properties in High Elevation Forests

    OpenAIRE

    Ayres, Edward; Steltzer, Heidi; Berg, Sarah; Wallenstein, Matthew D.; Simmons, Breana L.; Wall, Diana H

    2009-01-01

    Background Previous studies have shown that plants often have species-specific effects on soil properties. In high elevation forests in the Southern Rocky Mountains, North America, areas that are dominated by a single tree species are often adjacent to areas dominated by another tree species. Here, we assessed soil properties beneath adjacent stands of trembling aspen, lodgepole pine, and Engelmann spruce, which are dominant tree species in this region and are distributed widely in North Amer...

  2. Regeneration dynamics of dominant tree species along an altitudinal gradient in moist temperate valley slopes of the Garhwal Himalaya

    Institute of Scientific and Technical Information of China (English)

    Sumeet Gairola; C.M.Sharma; S.K.Ghildiyal; Sarvesh Suyal

    2012-01-01

    The present study was undertaken in moist temperate forest of Mandal-Chopta area in the Garhwal region of Uttarakhand,India.The aim of the present study was to understand the regeneration dynamics of the dominant tree species along an altitudinal gradient in naturally regenerating,restricted access forest.The overall regeneration status was fairly high in the study area.Most of the native canopy and undercanopy dominants had frequent reproduction and expanding populations,which suggests the stability of forest structure/composition and further expansion of dominant species.The overall regeneration of trees in the forest had a greater contribution of middle and understorey species.Because of infrequent reproduction and declining populations of some of the dominant native species viz.,Abies pindrow,Alnus nepalensis and Betula alnoides,structural/compositional changes in the future are expected in respective forests dominated by them.Abies pindrow and Taxus baccata need immediate attention by forest managers for their survival in the area.Seedlings were found to be more prone to competition from herb and shrubs than saplings.

  3. Changes in canopy structure and ant assemblages affect soil ecosystem variables as a foundation species declines:Ecosphere

    OpenAIRE

    Kendrick, Joseph A.; Ribbons, Relena Rose; Classen, Aimee Taylor; Ellison, Aaron M.

    2015-01-01

    The decline of Tsuga canadensis (eastern hemlock)?a foundation tree species?due to infestation by Adelges tsugae (hemlock woolly adelgid) or its complete removal from a stand by salvage logging dramatically affects associated faunal assemblages. Among these assemblages, species composition (richness and abundance) of ants increases rapidly as T. canadensis is lost from the stands. Because ants live and forage at the litter-soil interface, we hypothesized that environmental changes caused by h...

  4. Seasonal and Inter-annual Variation in Wood Production in Tropical Trees on Barro Colorado Island, Panama, is Related to Local Climate and Species Functional Traits

    Science.gov (United States)

    Cushman, K.; Muller-Landau, H. C.; Kellner, J. R.; Wright, S. J.; Condit, R.; Detto, M.; Tribble, C. M.

    2015-12-01

    Tropical forest carbon budgets play a major role in global carbon dynamics, but the responses of tropical forests to current and future inter-annual climatic variation remains highly uncertain. Better predictions of future tropical forest carbon fluxes require an improved understanding of how different species of tropical trees respond to changes in climate at seasonal and inter-annual temporal scales. We installed dendrometer bands on a size-stratified sample of 2000 trees in old growth forest on Barro Colorado Island, Panama, a moist lowland forest that experiences an annual dry season of approximately four months. Tree diameters were measured at the beginning and end of the rainy season since 2008. Additionally, we recorded the canopy illumination level, canopy intactness, and liana coverage of all trees during each census. We used linear mixed-effects models to evaluate how tree growth was related to seasonal and interannual variation in local climate, tree condition, and species identity, and how species identity effects related to tree functional traits. Climatic variables considered included precipitation, solar radiation, soil moisture, and climatological water deficit, and were all calculated from high-quality on-site measurements. Functional traits considered included wood density, maximum adult stature, deciduousness, and drought tolerance. We found that annual wood production was positively related to water availability, with higher growth in wetter years. Species varied in their response to seasonal water availability, with some species showing more pronounced reduction of growth during the dry season when water availability is limited. Interspecific variation in seasonal and interannual growth patterns was related to life-history strategies and species functional traits. The finding of higher growth in wetter years is consistent with previous tree ring studies conducted on a small subset of species with reliable annual rings. Together with previous

  5. A new species of parasitic wasp Neastymachus Girault (Hymenoptera: Chalcidoidea: Encyrtidae collected by fogging Vateria indic a L. (Dipterocarpaceae canopy in the Western Ghats of India

    Directory of Open Access Journals (Sweden)

    S. Singh

    2012-08-01

    Full Text Available A new species of the encyrtid genus Neastymachus (N. punctatiscutellum Singh, sp. nov. is described from a female specimen collected from the Western Ghats of India. It was collected by fogging the canopy of Vateria indica L. (Dipterocarpaceae. A key to the females of the Afrotropical, Australian and Oriental species is also given.

  6. Tree Growth Prediction in Relation to Simple Set of Site Quality Indicators for Six Native Tree Species in the Philippines

    Directory of Open Access Journals (Sweden)

    F. Santos Martin

    2010-01-01

    Full Text Available The gain in precision to explain the variation on tree growth performance as a function of a set of site indicators was analysed in a stepwise form, increasing its complexity and costs. Six native timber tree species were commonly found on farmer's fields and planted under different types of agroforestry systems. Localization of trees to be used for measurement was achieved through individual interviews to assess timing of introduction of trees. Results proved that native tree species planted on farmers' fields have similar growth rate other exotic timber species as Swietenia macrophylla that are widely spread in the Philippines. Nevertheless, the large fraction of the variation in tree performance that could not be explained by the biophysical site indicators measured implies that farmers take considerable risk in planting trees on the basis of current “scientific” knowledge. The complement of “site characteristics” is probably “management”, and the low determination of tree growth by site properties may in fact be good news for the farmers.

  7. Biogenic volatile organic compound emissions from nine tree species used in an urban tree-planting program

    Science.gov (United States)

    Curtis, A. J.; Helmig, D.; Baroch, C.; Daly, R.; Davis, S.

    2014-10-01

    The biogenic volatile organic compound (BVOC) emissions of nine urban tree species were studied to assess the air quality impacts from planting a large quantity of these trees in the City and County of Denver, Colorado, through the Mile High Million tree-planting initiative. The deciduous tree species studied were Sugar maple, Ohio buckeye, northern hackberry, Turkish hazelnut, London planetree, American basswood, Littleleaf linden, Valley Forge elm, and Japanese zelkova. These tree species were selected using the i-Tree Species Selector (itreetools.org). BVOC emissions from the selected tree species were investigated to evaluate the Species Selector data under the Colorado climate and environmental growing conditions. Individual tree species were subjected to branch enclosure experiments in which foliar emissions of BVOC were collected onto solid adsorbent cartridges. The cartridge samples were analyzed for monoterpenes (MT), sesquiterpenes (SQT), and other C10-C15 BVOC using thermal desorption-gas chromatography-flame ionization detection/mass spectroscopy (GC-FID/MS). Individual compounds and their emission rates (ER) were identified. MT were observed in all tree species, exhibiting the following total MT basal emission rates (BER; with a 1-σ lower bound, upper bound uncertainty window): Sugar maple, 0.07 (0.02, 0.11) μg g-1 h-1; London planetree, 0.15 (0.02, 0.27) μg g-1 h-1; northern hackberry, 0.33 (0.09, 0.57) μg g-1 h-1; Japanese zelkova, 0.42 (0.26, 0.58) μg g-1 h-1; Littleleaf linden, 0.71 (0.33, 1.09) μg g-1 h-1; Valley Forge elm, 0.96 (0.01, 1.92) μg g-1 h-1; Turkish hazelnut, 1.30 (0.32, 2.23) μg g-1 h-1; American basswood, 1.50 (0.40, 2.70) μg g-1 h-1; and Ohio buckeye, 6.61 (1.76, 11.47) μg g-1 h-1. SQT emissions were seen in five tree species with total SQT BER of: London planetree, 0.11 (0.01, 0.20) μg g-1 h-1; Japanese zelkova, 0.11 (0.05, 0.16) μg g-1 h-1; Littleleaf linden, 0.13 (0.06, 0.21) μg g-1 h-1; northern hackberry, 0.20 (0

  8. Litter Fall and Its Decomposition in Sapium sebiferum Roxb.: An Invasive Tree Species in Western Himalaya

    OpenAIRE

    Vikrant Jaryan; Sanjay Kr. Uniyal; Gupta, R. C.; Singh, R.D.

    2014-01-01

    Recognizing that high litter fall and its rapid decomposition are key traits of invasive species, litter fall and its decay in Sapium sebiferum Roxb. were studied in Palampur. For this, litter traps of dimension 50 × 50 × 50 cm3 were placed in under-canopy and canopy gap of the species. Litter fall was monitored monthly and segregated into different components. For litter decay studies, litter bags of dimension 25 × 20 cm2 with a mesh size 2 mm were used and the same were analyzed on a fortni...

  9. Vertical stratification of beetles (Coleoptera) and flies (Diptera) in temperate forest canopies.

    Science.gov (United States)

    Maguire, Dorothy Y; Robert, Katleen; Brochu, Kristen; Larrivée, Maxim; Buddle, Christopher M; Wheeler, Terry A

    2014-02-01

    Forest canopies support high arthropod biodiversity, but in temperate canopies, little is known about the spatial distribution of these arthropods. This is an important first step toward understanding ecological roles of insects in temperate canopies. The objective of this study was to assess differences in the species composition of two dominant and diverse taxa (Diptera and Coleoptera) along a vertical gradient in temperate deciduous forest canopies. Five sugar maple trees from each of three deciduous forest sites in southern Quebec were sampled using a combination of window and trunk traps placed in three vertical strata (understory, mid-canopy, and upper-canopy) for three sampling periods throughout the summer. Coleoptera species richness and abundance did not differ between canopy heights, but more specimens and species of Diptera were collected in the upper-canopy. Community composition of Coleoptera and Diptera varied significantly by trap height. Window traps collected more specimens and species of Coleoptera than trunk traps, although both trap types should be used to maximize representation of the entire Coleoptera community. There were no differences in abundance, diversity, or composition of Diptera collected between trap types. Our data confirm the relevance of sampling all strata in a forest when studying canopy arthropod biodiversity. PMID:24472199

  10. Vertical stratification of beetles (Coleoptera) and flies (Diptera) in temperate forest canopies.

    Science.gov (United States)

    Maguire, Dorothy Y; Robert, Katleen; Brochu, Kristen; Larrivée, Maxim; Buddle, Christopher M; Wheeler, Terry A

    2014-02-01

    Forest canopies support high arthropod biodiversity, but in temperate canopies, little is known about the spatial distribution of these arthropods. This is an important first step toward understanding ecological roles of insects in temperate canopies. The objective of this study was to assess differences in the species composition of two dominant and diverse taxa (Diptera and Coleoptera) along a vertical gradient in temperate deciduous forest canopies. Five sugar maple trees from each of three deciduous forest sites in southern Quebec were sampled using a combination of window and trunk traps placed in three vertical strata (understory, mid-canopy, and upper-canopy) for three sampling periods throughout the summer. Coleoptera species richness and abundance did not differ between canopy heights, but more specimens and species of Diptera were collected in the upper-canopy. Community composition of Coleoptera and Diptera varied significantly by trap height. Window traps collected more specimens and species of Coleoptera than trunk traps, although both trap types should be used to maximize representation of the entire Coleoptera community. There were no differences in abundance, diversity, or composition of Diptera collected between trap types. Our data confirm the relevance of sampling all strata in a forest when studying canopy arthropod biodiversity.

  11. Household Tree Planting in Tigrai, Northern Ethiopia: Tree Species, Purposes, and Determinants

    OpenAIRE

    Gebreegziabher, Zenebe; Mekonnen, Alemu; Kassie, Menale; Köhlin, Gunnar

    2010-01-01

    Trees have multiple purposes in rural Ethiopia, providing significant economic and ecological benefits. Planting trees supplies rural households with wood products for their own consumption, as well for sale, and decreases soil degradation. We used cross-sectional household-level data to analyze the determinants of household tree planting and explored the most important tree attributes or purpose(s) that enhance the propensity to plant trees. We set up a sample selection framework that simult...

  12. Iodine uptake and distribution in horticultural and fruit tree species

    Directory of Open Access Journals (Sweden)

    Alessandra Caffagni

    2012-07-01

    Full Text Available Iodine is an essential microelement for humans and iodine deficiency disorder (IDD is one of the most widespread nutrient-deficiency diseases in the world. Iodine biofortification of plants provides an attractive opportunity to increase iodine intake in humans and to prevent and control IDD. This study was conducted to investigate the iodine uptake and accumulation in edible portion of two fruit trees: plum and nectarine, and two horticultural crops: tomato and potato. Two type of iodine treatments (soil and foliar spray application, and, for fresh market tomato, two production systems (open field and greenhouse hydroponic culture were tested. The distribution of iodine in potato stem and leaves, and in plum tree fruits, leaves, and branches was investigated. Iodine content of potato tubers after postharvest storage and processing (cooking, and iodine content of nectarine fruits after postharvest storage and processing (peeling were also determined. Differences in iodine accumulation were observed among the four crops, between applications, and between production systems. In open field, the maximum iodine content ranged from 9.5 and 14.3 μg 100 g−1 for plum and nectarine fruit, to 89.4 and 144.0 μg 100 g−1 for potato tuber and tomato fruit, respectively. These results showed that nectarine and plum tree accumulated significantly lower amounts of iodine in their edible tissues, in comparison with potato and tomato. The experiments also indicated hydroponic culture as the most efficient system for iodine uptake in tomato, since its fresh fruits accumulated up to 2423 μg 100 g−1 of iodine. Iodine was stored mainly in the leaves, in all species investigated. Only a small portion of iodine was moved to plum tree branches and fruits, and to potato stems and tubers. No differences in iodine content after fruit peeling was observed. A significant increase in iodine content of potato was observed after baking, whereas a significant decrease was

  13. Effects of tree species on soil properties in a forest of the northeastern United States

    NARCIS (Netherlands)

    Dijkstra, F.A.

    2001-01-01

    Large differences in soil pH and available Ca in the surface soil exist among tree species growing in a mixed hardwood forest in northwestern Connecticut. The observed association between tree species and specific soil chemical properties within mixed-species stands implies that changes in the distr

  14. Water loss estimates for five recently transplanted landscape tree species in a semi-arid climate

    OpenAIRE

    Montague, Thayne; Kjelgren, Roger; Allen, Rick; Wester, David

    2004-01-01

    Over three growing seasons (1994-1996), water loss of five recently transplanted, balled and burlaped (B&B) tree species was investigated using below-ground, electronic weighing lysimeters. For each species, actual tree water loss was correlated with reference evapotranspiration (ETo) to create a water loss multiplier. At the beginning of each growing season a single tree was planted into each lysimeter. Selected species were London planetree (Platanus x acerifolia 'Bloodgood'), corkscrew ...

  15. Tree species diversity effects on soil microbial biomass, diversity and activity across European forest types

    OpenAIRE

    Carnol, Monique; Baeten, Lander; Bosman, Bernard; De Wandeler, Hans; Muys, Bart

    2014-01-01

    Increasing tree species diversity in forests might contribute to ecosystem-service maintenance, as well as to the reconciliation of regulating, provisioning and supporting services within the frame of multifunctional and sustainable forestry. Individual tree species influence biogeochemical cycling through element deposition (throughfall, litterfall), and through microbial activities in the soil. Yet, the influence of mixing tree species on these ecosystem processes is unclear, in particular ...

  16. Growth analysis on dominant tree species in Guniujiang nature reserve%牯牛降自然保护区优势树种生长分析

    Institute of Scientific and Technical Information of China (English)

    程希平; 杨晓军; 巩合德; 马月伟; 吴利华

    2013-01-01

    [Objective]The study researched the ecological characteristics and growth dynamics of dominant tree species in Guniujiang nature reserve in order to provide reference for the ecological characteristics research and dominant tree species management methods for P. massoniana and C. lanceolata tree species. [ Method ] Based on the establishment of permanent plots, the relationships between diameter class structure, DBH, tree height, and diameter growth rings of dominant tree species P. massoniana and C. lanceolata were investigated and analyzed. [ Result ] Results showed that P. massoniana dominated the canopy layer, but P. massoniana sapling was rare, overall distribution C. lanceolata was considered to be the subdominant tree species in the forest distribution scale. Tree rings showed that the age of two dominant species were similar, but the DBH growth increment in P. massoniana was greater than that in C. lanceolata; also, the tree height growth of P. massoniana was greater than that of C. lanceolata. [Conclusion]In the current mature forest canopy occupancy , the dominance of P. massoniana will be reduced while the dominance of C. lanceolata will gradually increase.%[目的]研究牯牛降自然保护区优势树种的生态特征与生长动态,为探究马尾松—杉木优势树种的生态特征林分管理方法提供参考依据.[方法]在设立固定样地的基础上,调查并分析了优势树种马尾松、杉木的径级结构、胸径生长、年轮、树高和胸径关系.[结果]调查样地内的马尾松为第一优势种,但幼树较稀少,林冠下实生与萌芽大量分布的杉木为亚优势种;树木年轮显示出两优势树种的树龄相近,但马尾松的胸径生长量大于杉木,树高生长量也比杉木大.[结论]成熟林林冠层马尾松在牯牛降自然保护区的优势地位会降低,而杉木的优势地位会逐渐扩大.

  17. Prospect of Milicia excelsa (Welw. C. Berg for Multi-Tree Species Agroforestry

    Directory of Open Access Journals (Sweden)

    Alfred Ossai Onefeli

    2015-11-01

    Full Text Available Background and Purpose: The population of most of our economically indigenous tree species in Nigeria is declining. Human activities and agricultural practices have been the ultimate contributors to this decrease. In order to ameliorate the conflict between agriculture and forestry, agroforestry was introduced. However, most of the practiced agroforestry is based on single tree species. Agroforestry practiced using single tree species have been reported to be ecologically staggered and therefore it is pertinent that phytosociology of trees with agroforestry potential is studied in order to improve the sustainability of human livelihood. Materials and Methods: This study was carried out in the University of Ibadan’s campus forest. The data were collected on Milicia excelsa (Welw. C. Berg by enumerating the tree species and also by identifying and enumerating the tree species associated with the subject tree (Milicia excelsa. Statistical analysis was done using percentages, Chi-square and charts. Results: A total of 49 individual Milicia excelsa were encountered in the study area. The results show 31 woody tree species associated with Milicia excelsa. Of all the associates Azadirachta indica A.Juss. happened to be the best one, having an average distance of 5.4 m to the subject tree. The sex ratio of Milicia excelsa was discovered to be approximately 1:1. Conclusions: Based on the obtained results of this research it may be concluded that Milicia excelsa has the prospect of being used in agroforestry in multi-tree species systems.

  18. Temporal changes of soil respiration under different tree species.

    Science.gov (United States)

    Akburak, Serdar; Makineci, Ender

    2013-04-01

    Soil respiration rates were measured monthly (from April 2007 to March 2008) under four adjacent coniferous plantation sites [Oriental spruce (Picea orientalis L.), Austrian pine (Pinus nigra Arnold), Turkish fir (Abies bornmulleriana L.), and Scots pine (Pinus sylvestris L.)] and adjacent natural Sessile oak forest (Quercus petraea L.) in Belgrad Forest-Istanbul/Turkey. Also, soil moisture, soil temperature, and fine root biomass were determined to identify the underlying environmental variables among sites which are most likely causing differences in soil respiration. Mean annual soil moisture was determined to be between 6.3 % and 8.1 %, and mean annual temperature ranged from 13.0°C to 14.2°C under all species. Mean annual fine root biomass changed between 368.09 g/m(2) and 883.71 g/m(2) indicating significant differences among species. Except May 2007, monthly soil respiration rates show significantly difference among species. However, focusing on tree species, differences of mean annual respiration rates did not differ significantly. Mean annual soil respiration ranged from 0.56 to 1.09 g C/m(2)/day. The highest rates of soil respiration reached on autumn months and the lowest rates were determined on summer season. Soil temperature, soil moisture, and fine root biomass explain mean annual soil respiration rates at the highest under Austrian pine (R (2) = 0.562) and the lowest (R (2) = 0.223) under Turkish fir. PMID:22828980

  19. Relationships between MODIS black-sky shortwave albedo and airborne lidar based forest canopy structure

    Science.gov (United States)

    Korhonen, Lauri; Rautiainen, Miina; Arumäe, Tauri; Lang, Mait; Flewelling, James; Tokola, Timo; Stenberg, Pauline

    2016-04-01

    Albedo is one of the essential climate variables affecting the Earth's radiation balance. It is however not well understood how changes in forest canopy structure influence the albedo. Canopy structure can be mapped consistently for fairly large areas using airborne lidar sensors. Our objective was to study the relationships between MODIS shortwave black sky albedo product and lidar-based estimates of canopy structure in different biomes ranging from arctic to tropical. Our study is based on six structurally different forest sites located in Finland, Estonia, USA and Laos. Lidar-based mean height of the canopy, canopy cover and their transformations were used as predictor variables to describe the canopy structure. Tree species composition was also included for the three sites where it was available. We noticed that the variables predicting albedo best were different in open and closed canopy forests. In closed canopy forests, the species information was more important than canopy structure variables (R2=0.31-0.32) and using only structural variables resulted in poor R2 (0.13-0.15). If the 500 m MODIS pixel contained a mixture of forests and other land cover types, the albedo was strongly related to the forest area percent. In open canopy forests, structural variables such as canopy cover or height explained albedo well, but species information still improved the models (R2=0.27-0.52). We obtained the highest R2=0.52 using only structural variables in Laos on a partially degraded tropical forest with large variation in canopy cover. The different canopy structure variables were often correlated and the one that provided the best model changed from site to site.

  20. Object-based Analysis for Extraction of Dominant Tree Species

    Institute of Scientific and Technical Information of China (English)

    Meiyun; SHAO; Xia; JING; Lu; WANG

    2015-01-01

    As forest is of great significance for our whole development and the sustainable plan is so focus on it. It is very urgent for us to have the whole distribution,stock volume and other related information about that. So the forest inventory program is on our schedule. Aiming at dealing with the problem in extraction of dominant tree species,we tested the highly hot method-object-based analysis. Based on the ALOS image data,we combined multi-resolution in e Cognition software and fuzzy classification algorithm. Through analyzing the segmentation results,we basically extract the spruce,the pine,the birch and the oak of the study area. Both the spectral and spatial characteristics were derived from those objects,and with the help of GLCM,we got the differences of each species. We use confusion matrix to do the Classification accuracy assessment compared with the actual ground data and this method showed a comparatively good precision as 87% with the kappa coefficient 0. 837.

  1. Contrasting effects of sampling scale on insect herbivores distribution in response to canopy structure.

    Science.gov (United States)

    Neves, Frederico S; Sperber, Carlos F; Campos, Ricardo I; Soares, Janaína P; Ribeiro, Sérvio P

    2013-03-01

    Species diversity of insect herbivores associated to canopy may vary local and geographically responding to distinct factors at different spatial scales. The aim of this study was to investigate how forest canopy structure affects insect herbivore species richness and abundance depending on feeding guilds' specificities. We tested the hypothesis that habitat structure affects insect herbivore species richness and abundance differently to sap-sucking and chewing herbivore guilds. Two spatial scales were evaluated: inside tree crowns (fine spatial cale) and canopy regions (coarse spatial scale). In three sampling sites we measured 120 tree crowns, grouped n five points with four contiguous tree crowns. Insects were sampled by beating method from each crown and data were summed up for analyzing each canopy region. In crowns (fine spatial scale) we measured habitat tructure: trunk circumference, tree height, canopy depth, number of ramifications and maximum ramification level. In each point, defined as a canopy region (coarse spatial scale), we measured habitat structure using a vertical cylindrical transect: tree species richness, leaf area, sum of strata heights and maximum canopy height. A principal component analysis based on the measured variables for each spatial scale was run to estimate habitat structure parameters. To test the effects of habitat structure upon herbivores, different general linear models were adjusted using the first two principal components as explanatory variables. Sap-sucking insect species richness and all herbivore abundances increased with size of crown at fine spatial scale. On the other hand, chewer species richness and abundance increased with resource quantity at coarse scale. Feeding specialization, resources availability, and agility are discussed as ecological causes of the found pattern.

  2. Species tree estimation for the late blight pathogen, Phytophthora infestans, and close relatives.

    Directory of Open Access Journals (Sweden)

    Jaime E Blair

    Full Text Available To better understand the evolutionary history of a group of organisms, an accurate estimate of the species phylogeny must be known. Traditionally, gene trees have served as a proxy for the species tree, although it was acknowledged early on that these trees represented different evolutionary processes. Discordances among gene trees and between the gene trees and the species tree are also expected in closely related species that have rapidly diverged, due to processes such as the incomplete sorting of ancestral polymorphisms. Recently, methods have been developed for the explicit estimation of species trees, using information from multilocus gene trees while accommodating heterogeneity among them. Here we have used three distinct approaches to estimate the species tree for five Phytophthora pathogens, including P. infestans, the causal agent of late blight disease in potato and tomato. Our concatenation-based "supergene" approach was unable to resolve relationships even with data from both the nuclear and mitochondrial genomes, and from multiple isolates per species. Our multispecies coalescent approach using both Bayesian and maximum likelihood methods was able to estimate a moderately supported species tree showing a close relationship among P. infestans, P. andina, and P. ipomoeae. The topology of the species tree was also identical to the dominant phylogenetic history estimated in our third approach, Bayesian concordance analysis. Our results support previous suggestions that P. andina is a hybrid species, with P. infestans representing one parental lineage. The other parental lineage is not known, but represents an independent evolutionary lineage more closely related to P. ipomoeae. While all five species likely originated in the New World, further study is needed to determine when and under what conditions this hybridization event may have occurred.

  3. Early impacts of biological control on canopy cover and water use of the invasive saltcedar tree (Tamarix spp.) in western Nevada, USA

    Science.gov (United States)

    Pattison, R.R.; D'Antonio, C. M.; Dudley, T.L.; Allander, K.K.; Rice, B.

    2011-01-01

    The success of biological control programs is rarely assessed beyond population level impacts on the target organism. The question of whether a biological control agent can either partially or completely restore ecosystem services independent of population level control is therefore still open to discussion. Using observational and experimental approaches, we investigated the ability of the saltcedar leaf beetle [Diorhabda carinulata (Brull??) (Coleoptera: Chrysomelidae)] to reduce the water use of saltcedar trees (Tamarix ramosissima Ledeb.) in two sites (Humboldt and Walker Rivers) in Nevada, USA. At these sites D. carinulata defoliated the majority of trees within 25 and 9 km, respectively, of the release location within 3 years. At the Humboldt site, D. carinulata reduced the canopy cover of trees adjacent to the release location by >90%. At a location 4 km away during the first year of defoliation, D. carinulata reduced peak (August) stem water use by 50-70% and stand transpiration (July to late September) by 75% (P = 0. 052). There was, however, no reduction in stem water use and stand transpiration during the second year of defoliation due to reduced beetle abundances at that location. At the Walker site, we measured stand evapotranspiration (ET) in the center of a large saltcedar stand and found that ET was highest immediately prior to D. carinulata arrival, dropped dramatically with defoliation, and remained low through the subsequent 2 years of the study. In contrast, near the perimeter of the stand, D. carinulata did not reduce sap flow, partly because of low rates of defoliation but also because of increased water use per unit leaf area in response to defoliation. Taken together, our results provide evidence that in the early stages of population expansion D. carinulata can lead to substantial declines in saltcedar water use. The extent of these declines varies spatially and temporally and is dependent on saltcedar compensatory responses along with D

  4. Landscape variation in tree species richness in northern Iran forests.

    Directory of Open Access Journals (Sweden)

    Charles P-A Bourque

    Full Text Available Mapping landscape variation in tree species richness (SR is essential to the long term management and conservation of forest ecosystems. The current study examines the prospect of mapping field assessments of SR in a high-elevation, deciduous forest in northern Iran as a function of 16 biophysical variables representative of the area's unique physiography, including topography and coastal placement, biophysical environment, and forests. Basic to this study is the development of moderate-resolution biophysical surfaces and associated plot-estimates for 202 permanent sampling plots. The biophysical variables include: (i three topographic variables generated directly from the area's digital terrain model; (ii four ecophysiologically-relevant variables derived from process models or from first principles; and (iii seven variables of Landsat-8-acquired surface reflectance and two, of surface radiance. With symbolic regression, it was shown that only four of the 16 variables were needed to explain 85% of observed plot-level variation in SR (i.e., wind velocity, surface reflectance of blue light, and topographic wetness indices representative of soil water content, yielding mean-absolute and root-mean-squared error of 0.50 and 0.78, respectively. Overall, localised calculations of wind velocity and surface reflectance of blue light explained about 63% of observed variation in SR, with wind velocity accounting for 51% of that variation. The remaining 22% was explained by linear combinations of soil-water-related topographic indices and associated thresholds. In general, SR and diversity tended to be greatest for plots dominated by Carpinus betulus (involving ≥ 33% of all trees in a plot, than by Fagus orientalis (median difference of one species. This study provides a significant step towards describing landscape variation in SR as a function of modelled and satellite-based information and symbolic regression. Methods in this study are sufficiently

  5. The influence of the forest canopy on nutrient cycling.

    Science.gov (United States)

    Prescott, Cindy E

    2002-11-01

    Rates of key soil processes involved in recycling of nutrients in forests are governed by temperature and moisture conditions and by the chemical and physical nature of the litter. The forest canopy influences all of these factors and thus has a large influence on nutrient cycling. The increased availability of nutrients in soil in clearcuts illustrates how the canopy retains nutrients (especially N) on site, both by storing nutrients in foliage and through the steady input of available C in litter. The idea that faster decomposition is responsible for the flush of nitrate in clearcuts has not been supported by experimental evidence. Soil N availability increases in canopy gaps as small as 0.1 ha, so natural disturbances or partial harvesting practices that increase the complexity of the canopy by creating gaps will similarly increase the spatial variability in soil N cycling and availability within the forest. Canopy characteristics affect the amount and composition of leaf litter produced, which largely determines the amount of nutrients to be recycled and the resulting nutrient availability. Although effects of tree species on soil nutrient availability were thought to be brought about largely through differences in the decomposition rate of their foliar litter, recent studies indicate that the effect of tree species can be better predicted from the mass and nutrient content of litter produced, hence total nutrient return, than from litter decay rate. The greater canopy complexity in mixed species forests creates similar heterogeneity in nutritional characteristics of the forest floor. Site differences in slope position, parent material and soil texture lead to variation in species composition and productivity of forests, and thus in the nature and amount of litter produced. Through this positive feedback, the canopy accentuates inherent differences in site fertility. PMID:12414379

  6. The relationship between canopy cover and colony size of the wood ant Formica lugubris--implications for the thermal effects on a keystone ant species.

    Directory of Open Access Journals (Sweden)

    Yi-Huei Chen

    Full Text Available Climate change may affect ecosystems and biodiversity through the impacts of rising temperature on species' body size. In terms of physiology and genetics, the colony is the unit of selection for ants so colony size can be considered the body size of a colony. For polydomous ant species, a colony is spread across several nests. This study aims to clarify how climate change may influence an ecologically significant ant species group by investigating thermal effects on wood ant colony size. The strong link between canopy cover and the local temperatures of wood ant's nesting location provides a feasible approach for our study. Our results showed that nests were larger in shadier areas where the thermal environment was colder and more stable compared to open areas. Colonies (sum of nests in a polydomous colony also tended to be larger in shadier areas than in open areas. In addition to temperature, our results supported that food resource availability may be an additional factor mediating the relationship between canopy cover and nest size. The effects of canopy cover on total colony size may act at the nest level because of the positive relationship between total colony size and mean nest size, rather than at the colony level due to lack of link between canopy cover and number of nests per colony. Causal relationships between the environment and the life-history characteristics may suggest possible future impacts of climate change on these species.

  7. The description of Paramblynotus delaneyi (Hymenoptera: Liopteridae), a new species from Joshua Tree National Park

    Science.gov (United States)

    A new species, Paramblynotus delaneyi (Hymenoptera: Liopteridae), is described and characters separating it from the Nearctic species P. zonatus Weld and P. virginianus Liu are discussed. A discussion of the insect biodiversity survey at Joshua Tree National Park is provided....

  8. Inferring duplications, losses, transfers and incomplete lineage sorting with nonbinary species trees

    OpenAIRE

    Stolzer, Maureen; Lai, Han; Xu, Minli; Sathaye, Deepa; Vernot, Benjamin; Durand, Dannie

    2012-01-01

    Motivation: Gene duplication (D), transfer (T), loss (L) and incomplete lineage sorting (I) are crucial to the evolution of gene families and the emergence of novel functions. The history of these events can be inferred via comparison of gene and species trees, a process called reconciliation, yet current reconciliation algorithms model only a subset of these evolutionary processes. Results: We present an algorithm to reconcile a binary gene tree with a nonbinary species tree under a DTLI par...

  9. Classification of savanna tree species, in the Greater Kruger National Park region, by integrating hyperspectral and LiDAR data in a Random Forest data mining environment

    Science.gov (United States)

    Naidoo, L.; Cho, M. A.; Mathieu, R.; Asner, G.

    2012-04-01

    The accurate classification and mapping of individual trees at species level in the savanna ecosystem can provide numerous benefits for the managerial authorities. Such benefits include the mapping of economically useful tree species, which are a key source of food production and fuel wood for the local communities, and of problematic alien invasive and bush encroaching species, which can threaten the integrity of the environment and livelihoods of the local communities. Species level mapping is particularly challenging in African savannas which are complex, heterogeneous, and open environments with high intra-species spectral variability due to differences in geology, topography, rainfall, herbivory and human impacts within relatively short distances. Savanna vegetation are also highly irregular in canopy and crown shape, height and other structural dimensions with a combination of open grassland patches and dense woody thicket - a stark contrast to the more homogeneous forest vegetation. This study classified eight common savanna tree species in the Greater Kruger National Park region, South Africa, using a combination of hyperspectral and Light Detection and Ranging (LiDAR)-derived structural parameters, in the form of seven predictor datasets, in an automated Random Forest modelling approach. The most important predictors, which were found to play an important role in the different classification models and contributed to the success of the hybrid dataset model when combined, were species tree height; NDVI; the chlorophyll b wavelength (466 nm) and a selection of raw, continuum removed and Spectral Angle Mapper (SAM) bands. It was also concluded that the hybrid predictor dataset Random Forest model yielded the highest classification accuracy and prediction success for the eight savanna tree species with an overall classification accuracy of 87.68% and KHAT value of 0.843.

  10. Indicator species of essential forest tree species in the Burdur district.

    Science.gov (United States)

    Negiz, Mehmet Güvenç; Eser, Yunus; Kuzugüdenll, Emre; Izkan, Kürşad

    2015-01-01

    The forests of Burdur district for long have been subjected to over grazing and individual selection. As a result of this, majority of the forest areas in the district were degraded. In the district, afforestation efforts included majority of forestry implementations. It is well known that selecting suitable species plays an important role for achieving afforestation efforts. In this context, knowing the indicator species among the target species would be used in afforestation efforts, studies on the interrelationships between environmental factors and target species distribution is vital for selecting suitable species for a given area. In this study, Anatolian Black pine (Pinus nigra), Red pine (Pinus brutia), Crimean juniper (Juniperus excelsa) and Taurus cedar (Cedrus libani), essential tree species, were considered as target species. The data taken from 100 sample plots in Burdur district was used. Interspecific correlation analysis was performed to determine the positive and negative indicator species among each of the target species. As a result of ICA, 2 positive (Berberis crataegina, Juniperus oxycedrus), 2 negative (Phillyrea latifolia, Quercus coccifera) for Crimean Juniper, I positive (Juniperus oxycedrus), 3 negative (Onopordium acanthium, Fraxinus ornus, Phillyrea latifolia) for Anatolian black pine, 3 positive (Paliurus spina-christi, Quercus coccifer, Crataegus orientalis), 2 negative (Berberis crataegina, Astragalus nanus) for Red pine and 3 positive (Berberis crataegina, Rhamnus oleoides, Astragalus prusianus) 2 negative (Paliurus spina-christi, Quercus cerris) for Taurus cedarwere defined as indicator plant species. In this way, practical information was obtained for selecting the most suitable species, among the target species, for afforestation efforts in Burdur district. PMID:26591889

  11. Calcium weathering in forested soils and the effedt of different tree species

    NARCIS (Netherlands)

    Dijkstra, F.A.; Breemen, van N.; Jongmans, A.G.; Davies, G.R.; Likens, G.E.

    2003-01-01

    Soil weathering can be an important mechanism to neutralize acidity in forest soils. Tree species may differ in their effect on or response to soil weathering. We used soil mineral data and the natural strontium isotope ratio Sr-87/Sr-86 as a tracer to identify the effect of tree species on the Ca w

  12. Tree species is the major factor explaining C:N ratios in European forest soils

    DEFF Research Database (Denmark)

    Cools, Nathalie; Vesterdal, Lars; De Vos, Bruno;

    2014-01-01

    mineral soil layers it was the humus type. Deposition and climatic variables were of minor importance at the European scale. Further analysis for eight main forest tree species individually, showed that the influence of environmental variables on C:N ratios was tree species dependent. For Aleppo pine...

  13. Spatial Distribution Patterns in the Very Rare and Species-Rich Picea chihuahuana Tree Community (Mexico).

    Science.gov (United States)

    Wehenkel, Christian; Brazão-Protázio, João Marcelo; Carrillo-Parra, Artemio; Martínez-Guerrero, José Hugo; Crecente-Campo, Felipe

    2015-01-01

    The very rare Mexican Picea chihuahuana tree community covers an area of no more than 300 ha in the Sierra Madre Occidental. This special tree community has been the subject of several studies aimed at learning more about the genetic structure and ecology of the species and the potential effects of climate change. The spatial distribution of trees is a result of many ecological processes and can affect the degree of competition between neighbouring trees, tree density, variability in size and distribution, regeneration, survival, growth, mortality, crown formation and the biological diversity within forest communities. Numerous scale-dependent measures have been established in order to describe spatial forest structure. The overall aim of most of these studies has been to obtain data to help design preservation and conservation strategies. In this study, we examined the spatial distribution pattern of trees in the P. chihuahuana tree community in 12 localities, in relation to i) tree stand density, ii) diameter distribution (vertical structure), iii) tree species diversity, iv) geographical latitude and v) tree dominance at a fine scale (in 0.25 ha plots), with the aim of obtaining a better understanding of the complex ecosystem processes and biological diversity. Because of the strongly mixed nature of this tree community, which often produces low population densities of each tree species and random tree fall gaps caused by tree death, we expect aggregated patterns in individual Picea chihuahuana trees and in the P. chihuahuana tree community, repulsive Picea patterns to other tree species and repulsive patterns of young to adult trees. Each location was represented by one plot of 50 x 50 m (0.25 ha) established in the centre of the tree community. The findings demonstrate that the hypothesis of aggregated tree pattern is not applicable to the mean pattern measured by Clark-Evans index, Uniform Angle index and Mean Directional index of the uneven-aged P

  14. Spatial Distribution Patterns in the Very Rare and Species-Rich Picea chihuahuana Tree Community (Mexico.

    Directory of Open Access Journals (Sweden)

    Christian Wehenkel

    Full Text Available The very rare Mexican Picea chihuahuana tree community covers an area of no more than 300 ha in the Sierra Madre Occidental. This special tree community has been the subject of several studies aimed at learning more about the genetic structure and ecology of the species and the potential effects of climate change. The spatial distribution of trees is a result of many ecological processes and can affect the degree of competition between neighbouring trees, tree density, variability in size and distribution, regeneration, survival, growth, mortality, crown formation and the biological diversity within forest communities. Numerous scale-dependent measures have been established in order to describe spatial forest structure. The overall aim of most of these studies has been to obtain data to help design preservation and conservation strategies. In this study, we examined the spatial distribution pattern of trees in the P. chihuahuana tree community in 12 localities, in relation to i tree stand density, ii diameter distribution (vertical structure, iii tree species diversity, iv geographical latitude and v tree dominance at a fine scale (in 0.25 ha plots, with the aim of obtaining a better understanding of the complex ecosystem processes and biological diversity. Because of the strongly mixed nature of this tree community, which often produces low population densities of each tree species and random tree fall gaps caused by tree death, we expect aggregated patterns in individual Picea chihuahuana trees and in the P. chihuahuana tree community, repulsive Picea patterns to other tree species and repulsive patterns of young to adult trees. Each location was represented by one plot of 50 x 50 m (0.25 ha established in the centre of the tree community. The findings demonstrate that the hypothesis of aggregated tree pattern is not applicable to the mean pattern measured by Clark-Evans index, Uniform Angle index and Mean Directional index of the uneven

  15. Spatial Distribution Patterns in the Very Rare and Species-Rich Picea chihuahuana Tree Community (Mexico)

    Science.gov (United States)

    Wehenkel, Christian; Brazão-Protázio, João Marcelo; Carrillo-Parra, Artemio; Martínez-Guerrero, José Hugo; Crecente-Campo, Felipe

    2015-01-01

    The very rare Mexican Picea chihuahuana tree community covers an area of no more than 300 ha in the Sierra Madre Occidental. This special tree community has been the subject of several studies aimed at learning more about the genetic structure and ecology of the species and the potential effects of climate change. The spatial distribution of trees is a result of many ecological processes and can affect the degree of competition between neighbouring trees, tree density, variability in size and distribution, regeneration, survival, growth, mortality, crown formation and the biological diversity within forest communities. Numerous scale-dependent measures have been established in order to describe spatial forest structure. The overall aim of most of these studies has been to obtain data to help design preservation and conservation strategies. In this study, we examined the spatial distribution pattern of trees in the P. chihuahuana tree community in 12 localities, in relation to i) tree stand density, ii) diameter distribution (vertical structure), iii) tree species diversity, iv) geographical latitude and v) tree dominance at a fine scale (in 0.25 ha plots), with the aim of obtaining a better understanding of the complex ecosystem processes and biological diversity. Because of the strongly mixed nature of this tree community, which often produces low population densities of each tree species and random tree fall gaps caused by tree death, we expect aggregated patterns in individual Picea chihuahuana trees and in the P. chihuahuana tree community, repulsive Picea patterns to other tree species and repulsive patterns of young to adult trees. Each location was represented by one plot of 50 x 50 m (0.25 ha) established in the centre of the tree community. The findings demonstrate that the hypothesis of aggregated tree pattern is not applicable to the mean pattern measured by Clark-Evans index, Uniform Angle index and Mean Directional index of the uneven-aged P

  16. Spatial Distribution Patterns in the Very Rare and Species-Rich Picea chihuahuana Tree Community (Mexico).

    Science.gov (United States)

    Wehenkel, Christian; Brazão-Protázio, João Marcelo; Carrillo-Parra, Artemio; Martínez-Guerrero, José Hugo; Crecente-Campo, Felipe

    2015-01-01

    The very rare Mexican Picea chihuahuana tree community covers an area of no more than 300 ha in the Sierra Madre Occidental. This special tree community has been the subject of several studies aimed at learning more about the genetic structure and ecology of the species and the potential effects of climate change. The spatial distribution of trees is a result of many ecological processes and can affect the degree of competition between neighbouring trees, tree density, variability in size and distribution, regeneration, survival, growth, mortality, crown formation and the biological diversity within forest communities. Numerous scale-dependent measures have been established in order to describe spatial forest structure. The overall aim of most of these studies has been to obtain data to help design preservation and conservation strategies. In this study, we examined the spatial distribution pattern of trees in the P. chihuahuana tree community in 12 localities, in relation to i) tree stand density, ii) diameter distribution (vertical structure), iii) tree species diversity, iv) geographical latitude and v) tree dominance at a fine scale (in 0.25 ha plots), with the aim of obtaining a better understanding of the complex ecosystem processes and biological diversity. Because of the strongly mixed nature of this tree community, which often produces low population densities of each tree species and random tree fall gaps caused by tree death, we expect aggregated patterns in individual Picea chihuahuana trees and in the P. chihuahuana tree community, repulsive Picea patterns to other tree species and repulsive patterns of young to adult trees. Each location was represented by one plot of 50 x 50 m (0.25 ha) established in the centre of the tree community. The findings demonstrate that the hypothesis of aggregated tree pattern is not applicable to the mean pattern measured by Clark-Evans index, Uniform Angle index and Mean Directional index of the uneven-aged P

  17. 激光测距在果树冠层三维重构中的应用%The Application on 3-D Construction of Fruit tree Canopy Using Laser Ranging

    Institute of Scientific and Technical Information of China (English)

    刘华; 姚耀华

    2012-01-01

      随着计算机技术的发展和果园果树精细管理的现实需求,果树冠层的三维重构问题成为研究热点。本文采用激光传感器在不同高度对果树靶标冠层进行水平扫描测距;将从果树不同方位测得的探测点坐标进行坐标转换,得到同一坐标系下的果树冠层三维点云;采用插值法重构模型树冠层三维轮廓。试验结果表明重构的冠层轮廓较为准确地反映了果树的外形轮廓。本文研究为采用激光传感器测距技术进行果树冠层三维重构与体积测量提供了前期研究基础。%  With the development of computer technology and the practical needs of the orchard management, so that three-dimensional reconstruction of tree canopy issue has become hot topic.In this paper,laser sensor was used to scan fruit tree canopy in a horizontal level plane at different heights; the three-dimensional point cloud of fruit tree canopy were getted through coordiante system transform that converted the measuring points coordinate getting from different measuring direction into the same coordinate system; the three dimensional of fruit tree canopy was constructed using interpolation method. The experiment result show that reconstruction of the canopy profile more accurately reflects the contour of the fruit tree. The study in this paper provides preliminary studies for three-dimensional reconstruction and volume measurements of fruit tree canopy using the laser ranging.

  18. Properties and flammability of major tree species in the Beijing area

    Institute of Scientific and Technical Information of China (English)

    Xiaoli WANG; Shukui NIU; Zhenguo KAN

    2009-01-01

    In order to examine correlations among the properties of tree species and to quantify the relationships between these properties and flammability, the properties of 20 tree species, consisting of heat of combustion, extractive contents, ash content, moisture content and basic density, were measured via experimental methods. In the first instance, the results show that, there are significant correlations between heat of combustion and extractive contents, ash content and basic density. Second, heat of combustion can be presented effectively in terms of linear regression models with extractive contents and ash content as independent variables. Third, a flammable model was developed based on four properties of tree species as independent variables, i.e., heat of combustion, extractive contents, ash content and moisture content. Finally, the flammability of 20 tree species is compared, ordered and ranked based on this flammable model. The conclusion is that flammability can be predicted from properties of tree species, which are significantly correlated among themselves.

  19. Weed community and growth under the canopy of trees adapted to the brazilian semi-arid region Comunidade e crescimento de plantas daninhas sob a copa de árvores adaptadas ao semi-árido brasileiro

    Directory of Open Access Journals (Sweden)

    P.S.L. Silva

    2010-01-01

    Full Text Available The objectives of this work were to evaluate the floristic composition and dry biomass of weeds under the canopy of seven perennial species adapted to the Semi-Arid region of Brazil, and correlate these characteristics with growth traits of the perennial species. The following perennial species were evaluated in two experiments (E1 and E2: mesquite (Prosopis juliflora, jucá (Caesalpinia ferrea, white popinac (Leucaena leucocephala, mofumbo (Combretum leprosum, neem (Azadirachata indica, sabiá (Mimosa caesalpiniaefolia and tamarind (Tamarindus indica. In E1, the seven species were evaluated in a random block design with four replicates and nine plants per plot. In E2, evaluation comprised four species (mesquite, jucá, white popinac, and tamarind in a random block design with eight replicates and nine plants per plot. A circle with an area of 1.77 m² was established around the trunk of each plant, two years after they were transplanted to the permanent location. The weeds collected within this circle were cut even with the ground, classified and weighed. At this time, plant height, and crown and stem diameters were evaluated in all trees of each plot. In E1 there were no differences between tree species as to weed frequency under their canopies; however, weed growth was smaller under the canopy of sabiá trees. Mesquite and sabiá had the greatest plant height and crown diameter means, but only sabiá had the greatest stem diameter. In E2, the perennial species were not different with regard to weed frequency and growth under their canopies, but mesquite had the greatest growth, as measured by plant height (with significant results for jucá as well and crown and stem diameter.Os objetivos deste trabalho foram avaliar a composição florística e a biomassa de plantas daninhas sob a copa de sete espécies perenes adaptadas à região semi-árida do Brasil, e correlacionar essas características com características do crescimento das esp

  20. Species-specific effects on throughfall kinetic energy below 12 subtropical tree species are related to leaf traits and tree architecture

    Science.gov (United States)

    Goebes, Philipp; Seitz, Steffen; Kühn, Peter; Kröber, Wenzel; Bruelheide, Helge; Li, Ying; von Oheimb, Goddert; Scholten, Thomas

    2015-04-01

    Soil erosion impacts environmental systems widely, especially in subtropical China where high erosion rates occur. The comprehension about the mechanisms that induce soil erosion on agricultural land is broad, but erosion processes below forests are only rarely understood. Especially throughfall kinetic energy (TKE) is influenced by forests and their structure as well as their succession in many ways. Today, many forests are monoculture tree stands due to economic reasons by providing timber, fuel and pulp wood. Therefore, this study investigates the role of different monoculture forest stands on TKE that were afforestated in 2008. The main questions are: Is TKE species-specific? What are characteristic leaf traits and tree architectural parameters that induce a species-specific effect on TKE and by what extend do they contribute to a mediation of species-specific effects on TKE? We measured TKE of 12 different species in subtropical China using sand-filled splash cups during five rainfall events in summer 2013. In addition, 14 leaf traits and tree architectural parameters were registered to link species-specific effects on TKE to vegetation parameters. Our results show that TKE is highly species-specific. Highest TKE was found below Choerospondias axillaris and Sapindus mukorossi, while Schima superba showed lowest TKE. The latter species can be regarded as key species for reduced erosion occurrence. This species effect is mediated by leaf habit, leaf area, leaf pinnation, leaf margin, tree ground diameter, crown base height, tree height, number of branches and LAI as biotic factors and rainfall amount as abiotic factor. Moreover, leaf habit, tree height and LA show high effect sizes on TKE and can be considered as major drivers evoking TKE differences below vegetation.

  1. Species tree discordance traces to phylogeographic clade boundaries in North American fence lizards (Sceloporus).

    Science.gov (United States)

    Leaché, Adam D

    2009-12-01

    I investigated the impacts of phylogeographic sampling decisions on species tree estimation in the Sceloporus undulatus species group, a recent radiation of small, insectivorous lizards connected by parapatric and peripatric distribution across North America, using a variety of species tree inference methods (Bayesian estimation of species trees, Bayesian untangling of concordance knots, and minimize deep coalescences). Phylogenetic analyses of 16 specimens representing 4 putative species within S. "undulatus" using complete (8 loci, >5.5 kb) and incomplete (29 loci, >23.6 kb) nuclear data sets result in species trees that share features with the mitochondrial DNA (mtDNA) genealogy at the phylogeographic level but provide new insights into the evolutionary history of the species group. The concatenated nuclear data and mtDNA data both recover 4 major clades connecting populations across North America; however, instances of discordance are localized at the contact zones between adjacent phylogeographic groups. A random sub-sampling experiment designed to vary the phylogeographic samples included across hundreds of replicate species tree inferences suggests that inaccurate species assignments can result in inferred phylogenetic relationships that are dependent upon which particular populations are used as exemplars to represent species and can lead to increased estimates of effective population size. For the phylogeographic data presented here, reassigning specimens with introgressed mtDNA genomes to their prospective species, or excluding them from the analysis altogether, produces species tree topologies that are distinctly different from analyses that utilize mtDNA-based species assignments. Evolutionary biologists working at the interface of phylogeography and phylogenetics are likely to encounter multiple processes influencing gene trees congruence, which increases the relevance of estimating species trees with multilocus nuclear data and models that accommodate

  2. Quantitative Analysis of Tree Species Diversity in Different Oak (Quercus spp.) Dominated Forests in Garhwal Himalaya, India

    OpenAIRE

    Gajendra SINGH; Gopal S. RAWAT

    2012-01-01

    Himalayan broad-leaved forests are mainly dominated by oak (Quercus spp.) species. Oak species with other tree species provide numerous ecosystem services and serve as lifeline for local inhabitants. Overall tree diversity and their status in different oak dominated forests viz., Quercus leucotrichophora (1500-2200 m), Q. floribunda (2201-2700 m) and Q. semecarpifolia (2701-3300 m) were studied in Garhwal, Himalaya. A total of 54 tree species (40 genera) in Q. leucotrichophora, 43 tree specie...

  3. Genetic variation in a tropical tree species influences the associated epiphytic plant and invertebrate communities in a complex forest ecosystem

    OpenAIRE

    Zytynska, Sharon E.; Fay, Michael F.; Penney, David; Preziosi, Richard F.

    2011-01-01

    Genetic differences among tree species, their hybrids and within tree species are known to influence associated ecological communities and ecosystem processes in areas of limited species diversity. The extent to which this same phenomenon occurs based on genetic variation within a single tree species, in a diverse complex ecosystem such as a tropical forest, is unknown. The level of biodiversity and complexity of the ecosystem may reduce the impact of a single tree species on associated commu...

  4. Soil respiration and rates of soil carbon turnover differ among six common European tree species

    DEFF Research Database (Denmark)

    Vesterdal, Lars; Elberling, Bo; Christiansen, Jesper Riis;

    2012-01-01

    The knowledge of tree species effects on soil organic carbon (C) turnover based on rigorous experimental designs is limited for common European deciduous tree species. We assessed soil respiration, and rates of C turnover in six tree species in a more than 30-year-old common garden experiment...... turnover indices that integrated the forest floor. The results suggests that specific traits of Norway spruce and these five common broadleaf forest species should be taken into account in the modelling of soil C stock dynamics over decades....

  5. Alien Plant Species Mountain Endemic Tree Species in Gunung Gede Pangrango National Park

    Directory of Open Access Journals (Sweden)

    Budi Utomo

    2012-09-01

    Full Text Available 800x600 Up to now, montane rain forest of Gunung Gede-Pangrango National Park, faces problem in the form of invasion of exotic plant species into the area.  Location of the area that borders with various land uses, such as Botanical Garden and agricultural land, make it very susceptible toward invasion of plant species from outside the area.  The collapse of large trees which normally constitute a mechanism of natural regeneration, was in fact stimulating the development of exotic species, particularly those which were invasive, inside the area. The objective of this research was to test the competitive ability of endemic species, which in this case was represented by Cleystocalyx operculata and Mischocarpus pentapetalus, toward exotic plant species, represented by Austroeupatoriun inulaefolium and Passiflora ligularis, during 5 months of study.  Growth rate of exotic plant species, as well as the dry weight biomass, were larger than those of endemic species.  Indirect estimation of competitive ability showed that competitive ability (β of endemic species were 4-5 times less, namely 0.0274 (for C. operculata and 0.0251 (for M. pentapetalus; as compared with those of exotic species, namely 0.125 (for P. ligularis and 0.1104 (for A. inulaefolium.  Direct test also proved that competitive ability (β of endemic species was lower than that of exotic species, as shown by relative crowding value   Estimation of future competitive ability, using diagram of input/ output ratio, showed also the disability of endemic species to compete with exotic species, where position of input/output ratio points were parallel with equilibrium line y=x. Considering those facts, there is urgent need for controlling these invasive exotic species inside the National Park area to maintain the sustainability of biodiversity and regeneration of endemic species in montane rain forest of Gunung Gede–Pangrango National Park.    Keywords: endemic, exotic, invasion

  6. Effect of Salt Stress on Transpiration and Ion Distribution in Seedlings of Four Tree Species

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    Transpiration rate and ion distribution of pagoda tree, walnut, velvet ash and poplar seedlings treated by NaCl solution of 0, 50, 100, 200 mmol·L-1 were studied. The results showed that there were significant differences in the response to NaCl among the four tree species. Na+ exclusion capacity of pagoda tree was the largest among the four species. The Na+ exclusion capacity of velvet ash was less than that of pagoda tree. Salt excretion capacity of velvet ash was limited. Its salt-tolerance was bigge...

  7. From natural forest to tree crops, co-domestication of forests and tree species: an overview.

    NARCIS (Netherlands)

    Wiersum, K.F.

    1997-01-01

    The process of domestication of tree crops has only been given limited attention. This process starts with the protection of natural forests and ends with the cultivation of domesticated tree crops. In this evolutionary process three types of human-influenced forest environments may be distinguished

  8. Soil magnetic susceptibility reflects soil moisture regimes and the adaptability of tree species to these regimes

    Science.gov (United States)

    Wang, J.-S.; Grimley, D.A.; Xu, C.; Dawson, J.O.

    2008-01-01

    Flooded, saturated or poorly drained soils are frequently anaerobic, leading to dissolution of the strongly magnetic minerals, magnetite and maghemite, and a corresponding decrease in soil magnetic susceptibility (MS). In this study of five temperate deciduous forests in east-central Illinois, USA, mean surface soil MS was significantly higher adjacent to upland tree species (31 ?? 10-5 SI) than adjacent to floodplain or lowland tree species (17 ?? 10-5 SI), when comparing regional soils with similar parent material of loessal silt. Although the sites differ in average soil MS for each tree species, the relative order of soil MS means for associated tree species at different locations is similar. Lowland tree species, Celtis occidentalis L., Ulmus americana L., Acer saccharinum L., Carya laciniosa (Michx. f.) Loud., and Fraxinus pennsylvanica Marsh. were associated with the lowest measured soil MS mean values overall and at each site. Tree species' flood tolerance rankings increased significantly, as soil MS values declined, the published rankings having significant correlations with soil MS values for the same species groups. The three published classifications of tree species' flood tolerance were significantly correlated with associated soil MS values at all sites, but most strongly at Allerton Park, the site with the widest range of soil drainage classes and MS values. Using soil MS measurements in forests with soil parent material containing similar initial levels of strongly magnetic minerals can provide a simple, rapid and quantitative method to classify soils according to hydric regimes, including dry conditions, and associated plant composition. Soil MS values thus have the capacity to quantify the continuum of hydric tolerances of tree species and guide tree species selection for reforestation. ?? 2007 Elsevier B.V. All rights reserved.

  9. Variation in leaf litter production and resorption of nutrients in abundant tree species in Nyungwe tropical montane rainforest in Rwanda

    Science.gov (United States)

    Nyirambangutse, Brigitte; Mirindi Dusenge, Eric; Nsabimana, Donat; Bizuru, Elias; Pleijel, Håkan; Uddling, Johan; Wallin, Göran

    2014-05-01

    African tropical rainforests play many roles from local to global scale as providers of resources and ecosystem services. Although covering 30% of the global rainforest, only few studies aiming to better understand the storage and fluxes of carbon and nutrients in these forests have been conducted. To answer questions related to these issues, we have established 15 permanent 0.5 ha plots where we compare carbon and nutrient fluxes of primary and secondary forest tree communities in a tropical montane forest in central Africa. The studies are conducted in Nyungwe montane tropical rain forest gazetted as a National Park to protect its extensive floral and faunal diversity covering an area of 970 km2. Nyungwe is located in Southwest Rwanda (2o17'-2o50'S, 29o07'-29o26A'E). The forest is ranging between 1600-2950 m.a.s.l. and is one of the most biologically important rainforest in Albertine Rift region in terms of Biodiversity. Nyungwe consists of a mixture of primary and secondary forest communities supporting a richness of plant and animal life. More than 260 species of trees and shrubs have been found in Nyungwe, including species endemic to the Albertine Rift. The forest has a climate with a mean annual temperature of 15.5oC and annual rainfall of ca 1850 mm yr-1, with July and August being the only months when rainfall drops. A part of this study is focusing on the dynamics of nutrients through leaf turnover. This turnover of leaves is regulated to maximize the carbon gain through canopy photosynthesis and resource-use efficiency of the plant. It is known that about half of leaf nitrogen is invested in photosynthetic apparatus and that there normally is a strong correlation between the photosynthetic capacity and leaf nitrogen per unit area. Hence leaf nitrogen is an important factor for canopy photosynthesis. However, leaves are produced, senesce and fall. Some nitrogen in the leaf is lost when leaves senesce but other is resorbed. The resorption of nitrogen

  10. CHARACTERIZATION OF FAST GROWING TREES SPECIES FOR ETHANOL PRODUCTION

    Directory of Open Access Journals (Sweden)

    P. V. ANBU*, K. T. PARTHIBAN1, I. SEKAR U. SIVAKUMAR3,S.UMESHKANNA1 ,V. SARAVANA P. DURAIRASU1

    2014-09-01

    Full Text Available The fast growing trees were had the acceptable growth, chemical composition and morphological properties that make it suitable for ethanol recovery. The growth attained average level from 1.57m to 3.73m at the end of ninth month. The chemical composition such as higher proportion of holocellulose and lower content of lignin of the fast growing trees expected the more ethanol recovery with minimum recalcitrant. Due to long fiber length, wider fiber width, and wide lumen diameter with thin cell wall thickness of the fast growing trees were preferable for ethanol conversion.

  11. Bioclimate and reproductive potential at the cold limit of European deciduous tree species

    OpenAIRE

    Kollas, Chris

    2013-01-01

    This thesis assessed factors that contribute to the explantion of the upper elevational and latitudinal limits of European broad-leaved tree species by using a set of ecological analysis, including in situ temperature measurements, a transplant experiment and a survey of the reproductive cycle and demography at the species limits. The following key questions were answered in five chapters: Do the elevational thermal limits of broad-leaved tree species correspond to their latitudinal t...

  12. Tree species of South America central savanna: endemism, marginal areas and the relationship with other biomes

    OpenAIRE

    Renata D. Françoso; Ricardo F. Haidar; Machado, Ricardo B.

    2016-01-01

    Biological knowledge is important for guidance of conservation polices. In the Cerrado, an extremely diverse biome, the last synthesis of floristic knowledge has more than ten years. To understand the progress on the information, our aim was quantify the tree species of the Cerrado, and assess their distribution. We compiled 167 inventories and rapid surveys of tree species, corresponding to 625 sites. We accessed the species distributions in the Brazilian biomes, and estimated the number of ...

  13. Local Distribution and coexistence of prevalent tree species in peat swamp forests of Central Kalimantan

    OpenAIRE

    Herwint Simbolon

    2009-01-01

    SIMBOLON, H. 2009. Local Distribution and coexistence of prevalent tree species in peat swamp forests of Central Kalimantan. Reinwardtia 12(5): 373–382. ⎯ A study on the distribution and coexistence of prevalent tree species in peat swamp forests was conducted at Lahei and Kelampangan, Central Kalimantan. The prevalent species in both sites were Calophyllum canum, Combretocarpus rotundatus, Cratoxylum glaucum, Ctenolophon parvifolius, Elaeocarpus petiolatus, with Palaquium cochleariifolium at...

  14. Identifying priority areas for Conservation in Mexican Tropical deciduous forest based on Tree Species

    OpenAIRE

    Eva M. Cué Bär; José Luis Villaseñor; Juan J. Monrroe; Guillermo Ibarra-Manríquez

    2006-01-01

    The main objective was to identify and rank areas for the conservation of exclusive, or nearly exclusive, tree species of the tropical deciduous forest in Mexico, a land cover type greatly endangered worldwide. A list of 425 tree species (67.5% endemic to Mexico), including 56 families and 185 genera registered at the state level, was compiled from an exhaustive revision of specialized floristic literature. The conservation status of these species was assessed by registering their presence in...

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

    OpenAIRE

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

    2003-01-01

    Aim: Tropical rain forests are often regarded as pristine and undisturbed by humans. In Central Africa, community-wide disturbances by natural causes are rare and therefore current theory predicts that natural gap phase dynamics structure tree species composition and diversity. However, the dominant tree species in many African forests recruit poorly, despite the presence of gaps. To explain this, we studied the disturbance history of a species-rich and structurally complex rain forest. Locat...

  16. CONSUMER'S SPECIE KNOWLEDGE AND THE VALUES OF NATURAL CHRISTMAS TREE CHARACTERISTICS

    OpenAIRE

    Davis, George C.

    1993-01-01

    Consumers' willingness to pay for natural Christmas tree characteristics are estimated. Differences in willingness to pay for characteristics by specie knowledge and lack of specie knowledge are tested. Differences in willingness to pay for characteristics by specie are also tested. The results suggests that willingness to pay measures differ by these separations of the sample and, ceteris paribus, sellers of natural Christmas trees could benefit by altering characteristics in accordance with...

  17. Seven new species of the Botryosphaeriaceae from baobab and other native trees in Western Australia.

    Science.gov (United States)

    Pavlic, Draginja; Wingfield, Michael J; Barber, Paul; Slippers, Bernard; Hardy, Giles E St J; Burgess, Treena I

    2008-01-01

    In this study seven new species of the Botryosphaeriaceae are described from baobab (Adansonia gibbosa) and surrounding endemic tree species growing in the Kimberley region of northwestern Australia. Members of the Botryosphaeriaceae were predominantly endophytes isolated from apparently healthy sapwood and bark of endemic trees; others were isolated from dying branches. Phylogenetic analyses of ITS and EF1-alpha sequence data revealed seven new species: Dothiorella longicollis, Fusicoccum ramosum, Lasiodiplodia margaritacea, Neoscytalidium novaehollandiae, Pseudofusicoccum adansoniae, P. ardesiacum and P. kimberleyense. PMID:19202840

  18. Hybrid-Lambda: simulation of multiple merger and Kingman gene genealogies in species networks and species trees

    OpenAIRE

    Zhu, Sha; Degnan, James H; Eldon, Bjarki

    2013-01-01

    Hybrid-Lambda is a software package that simulates gene trees under Kingman or two Lambda-coalescent processes within species networks or species trees. It is written in C++, and re- leased under GNU General Public License (GPL) version 3. Users can modify and make new dis- tribution under the terms of this license. For details of this license, visit http://www.gnu.org/licenses/. Hybrid Lambda is available at https://code.google.com/p/hybrid-lambda.

  19. Tree species as hosts for arbuscular mycorrhizal and dark septate endophyte fungi

    Institute of Scientific and Technical Information of China (English)

    E.Uma; K.Sathiyadash; J.Loganathan; T.Muthukumar

    2012-01-01

    A survey of 35 tree species (belonging to 28 genera in 19families) in Aliyar,South India was carried out to ascertain their arbuscular mycorrhizal (AM) and dark septate endophyte (DSE) fungal status.All the tree species examined had AM association.AM and DSE colonization is reported for the first time in 20 and 14 species respectively.Cooccurrence of AM and DSE was observed in 14 (40%) tree species.The extent of DSE colonization was inversely related to the extent of AM fungal colonization.Six tree species had Arum-type,18 had intermediatetype and 1l had typical Paris-type AM morphology.AM fungal spore morphotypes belonging to 11 species in two genera were isolated from the rhizosphere soil.AM fungal spore numbers were not related to the extent of AM colonization and Glomus dominated spore diversity.AM association individually and along with DSE were found respectively in the 63% and 44% of the economically important tree species.The occurrence of AM and DSE fungal association in economically important indigenous tree species indicates the possibility of exploiting this association in future conservation programmes of these species.

  20. Changes in canopy structure and ant assemblages affect soil ecosystem variables as a foundation species declines

    DEFF Research Database (Denmark)

    Kendrick, Joseph A.; Ribbons, Relena Rose; Classen, Aimee Taylor;

    2015-01-01

    in ant species composition would interact to alter soil ecosystem variables. In the Harvard Forest Hemlock Removal Experiment (HF-HeRE), established in 2003, T. canadensis in large plots were killed in place or logged and removed to mimic adelgid infestation or salvage harvesting, respectively. In 2006...... (richness and abundance) of ants increases rapidly as T. canadensis is lost from the stands. Because ants live and forage at the litter-soil interface, we hypothesized that environmental changes caused by hemlock loss (e.g., increased light and warmth at the forest floor, increased soil pH) and shifts...

  1. Soil carbon accumulation and nitrogen retention traits of four tree species grown in common gardens

    DEFF Research Database (Denmark)

    Gurmesa, Geshere Abdisa; Schmidt, Inger Kappel; Gundersen, Per;

    2013-01-01

    Tree species effects on soil carbon (C) accumulation are uncertain, especially with respect to the mineral soil C, and the consistency of such effects across soil types is not known. The interaction between C accumulation and nitrogen (N) retention among common tree species has also been little...... explored. Effects of four tree species on soil C and N stocks and soil water nitrate concentration below the root zone were evaluated in a common garden design replicated at eight sites in Denmark. The tree species were beech (Fagus sylvatica L.), oak (Quercus robur L.), larch (Larix leptolepis Kaempf......), and Norway spruce (Picea abies (L) Karst.). After four decades, there were significant differences in forest floor C stocks among all four species, and C stocks increased consistently in the order oak

  2. Conspecific plant-soil feedbacks of temperate tree species in the southern Appalachians, USA.

    Directory of Open Access Journals (Sweden)

    Kurt O Reinhart

    Full Text Available Many tree species have seedling recruitment patterns suggesting that they are affected by non-competitive distance-dependent sources of mortality. We conducted an experiment, with landscape-level replication, to identify cases of negative distance-dependent effects and whether variation in these effects corresponded with tree recruitment patterns in the southern Appalachian Mountains region. Specifically, soil was collected from 14 sites and used as inocula in a 62 day growth chamber experiment determining whether tree seedling growth was less when interacting with soil from conspecific (like than heterospecific (other tree species. Tests were performed on six tree species. Three of the tree species had been previously described as having greater recruitment around conspecifics (i.e. facilitator species group compared to the other half (i.e. inhibitor species group. We were then able to determine whether variation in negative distance-dependent effects corresponded with recruitment patterns in the field. Across the six species, none were negatively affected by soil inocula from conspecific relative to heterospecific sources. Most species (four of six were unaffected by soil source. Two species (Prunus serotina and Tsuga canadensis had enhanced growth in pots inoculated with soil from conspecific trees vs. heterospecifics. Species varied in their susceptibility to soil pathogens, but trends across all species revealed that species classified as inhibitors were not more negatively affected by conspecific than heterospecific soil inocula or more susceptible to pathogenic effects than facilitators. Although plant-soil biota interactions may be important for individual species and sites, it may be difficult to scale these interactions over space or levels of ecological organization. Generalizing the importance of plant-soil feedbacks or other factors across regional scales may be especially problematic for hyperdiverse temperate forests where

  3. Increasing the realism of projected tree species ranges by incorporating migration potential: an eastern US case study

    Science.gov (United States)

    Rogers, B. M.; Jantz, P.; Goetz, S. J.

    2015-12-01

    Models of vegetation distributions are used for a wide variety of purposes, from global assessments of biome shifts and biogeochemical feedbacks to local management planning. Dynamic vegetation models, mostly mechanistic in origin, are valuable for regional to global studies but remain limited for more local-scale applications, especially those that require species-specific responses to climate change. Species distribution models (SDMs) are broadly used for such applications, but these too have several outstanding limitations, one of the most prominent being a lack of dispersal and migration. Several hybrid models have recently been developed, but these generally require detailed parameterization of species-level attributes that may not be known. Here we present an approach to couple migration potential with SDM output for a large number of species in order to more realistically project future range shifts. We focus on 40 tree species in the eastern US of potential management concern, either because of their canopy dominance, ecosystem functions, or potential for utilizing future climates. Future climates were taken from a CMIP5 model ensemble average using RCP 4.5 and 8.5 scenarios. We used Random Forests to characterize current and future environmental suitability, and modeled migration as a negative exponential kernel that is affected by forest fragmentation and the density of current seed sources. We present results in a vulnerability framework relevant for a number of ongoing management activities in the region. We find an overarching pattern of northward and eastward range shifts, with high-elevation and northern species being the most adversely impacted. Because of limitations to migration, many newly suitable areas could not be utilized without active intervention. Only a few areas exhibited consistently favorable conditions that could be utilized by the relevant species, including the central Appalachian foothills and the Florida panhandle. We suggest that

  4. Characterization of Rosaceae tree species in a young Turkey oak-dominated coppice forest

    Directory of Open Access Journals (Sweden)

    Giulietti V

    2009-09-01

    Full Text Available First results of a trial carried out in an experimental area (“Comunità Montana Colline Metallifere”, Tuscany. After coppicing (winter 1998-1999, 77 Sorbus torminalis, Sorbus domestica and others valuable tree species were released on the whole of 220 standard trees per hectare. Aim of the present study was to estimate the opportunity to produce valuable timber from standards of sporadic tree species living into coppice forests. A research trial aimed at evaluating stem and crown quality as well as radial growth of standards after coppicing was carried out in an area 3 hectares wide. Wild service tree, Service tree and Turkey oak trees were analysed. Seven years after coppicing, the growth pattern of the different species, was also analysed by means of two structural transects. In the early phase after coppicing, root and stump suckers of both Sorbus species (especially Service tree are able to compete with Turkey oak sprouts as for height growth. In the following stage, the social regression of Sorbus trees is easily foreseeible because of the high competitive ability of Quercus. The good stem and crown shaping showed to be characters owned by a few Sorbus standards only. These were characterized as the largest-sized and early well-crown shaped trees. The same trees showed the highest dbh growth and developed few epicormic branches. A better targeted selection rule of valuable timber tree species to build up the standards’ stock is the recommended practice to improve forest biodiversity, as well as to create an economically important additional option to firewood, usually produced in these coppice forests.

  5. Is Tree Species Diversity or Species Identity the More Important Driver of Soil Carbon Stocks, C/N Ratio, and pH?

    DEFF Research Database (Denmark)

    Dawud, Seid Muhie; Raulund-Rasmussen, Karsten; Domisch, Timo;

    2016-01-01

    We explored tree species diversity effects on soil C stock, C/N ratio, and pH as compared with effects of tree species identity. We sampled forest floors and mineral soil (0–40 cm) in a diversity gradient of 1–5 tree species composed of conifers and broadleaves in Białowieża Forest, Poland. Diver...

  6. Modeling of forest canopy BRDF using DIRSIG

    Science.gov (United States)

    Rengarajan, Rajagopalan; Schott, John R.

    2016-05-01

    The characterization and temporal analysis of multispectral and hyperspectral data to extract the biophysical information of the Earth's surface can be significantly improved by understanding its aniosotropic reflectance properties, which are best described by a Bi-directional Reflectance Distribution Function (BRDF). The advancements in the field of remote sensing techniques and instrumentation have made hyperspectral BRDF measurements in the field possible using sophisticated goniometers. However, natural surfaces such as forest canopies impose limitations on both the data collection techniques, as well as, the range of illumination angles that can be collected from the field. These limitations can be mitigated by measuring BRDF in a virtual environment. This paper presents an approach to model the spectral BRDF of a forest canopy using the Digital Image and Remote Sensing Image Generation (DIRSIG) model. A synthetic forest canopy scene is constructed by modeling the 3D geometries of different tree species using OnyxTree software. The field collected spectra from the Harvard forest is used to represent the optical properties of the tree elements. The canopy radiative transfer is estimated using the DIRSIG model for specific view and illumination angles to generate BRDF measurements. A full hemispherical BRDF is generated by fitting the measured BRDF to a semi-empirical BRDF model. The results from fitting the model to the measurement indicates a root mean square error of less than 5% (2 reflectance units) relative to the forest's reflectance in the VIS-NIR-SWIR region. The process can be easily extended to generate a spectral BRDF library for various biomes.

  7. Tree diversity and species identity effects on soil fungi, protists and animals are context dependent.

    Science.gov (United States)

    Tedersoo, Leho; Bahram, Mohammad; Cajthaml, Tomáš; Põlme, Sergei; Hiiesalu, Indrek; Anslan, Sten; Harend, Helery; Buegger, Franz; Pritsch, Karin; Koricheva, Julia; Abarenkov, Kessy

    2016-02-01

    Plant species richness and the presence of certain influential species (sampling effect) drive the stability and functionality of ecosystems as well as primary production and biomass of consumers. However, little is known about these floristic effects on richness and community composition of soil biota in forest habitats owing to methodological constraints. We developed a DNA metabarcoding approach to identify the major eukaryote groups directly from soil with roughly species-level resolution. Using this method, we examined the effects of tree diversity and individual tree species on soil microbial biomass and taxonomic richness of soil biota in two experimental study systems in Finland and Estonia and accounted for edaphic variables and spatial autocorrelation. Our analyses revealed that the effects of tree diversity and individual species on soil biota are largely context dependent. Multiple regression and structural equation modelling suggested that biomass, soil pH, nutrients and tree species directly affect richness of different taxonomic groups. The community composition of most soil organisms was strongly correlated due to similar response to environmental predictors rather than causal relationships. On a local scale, soil resources and tree species have stronger effect on diversity of soil biota than tree species richness per se. PMID:26172210

  8. Coordination between water transport capacity, biomass growth, metabolic scaling and species stature in co-occurring shrub and tree species.

    Science.gov (United States)

    Smith, Duncan D; Sperry, John S

    2014-12-01

    The significance of xylem function and metabolic scaling theory begins from the idea that water transport is strongly coupled to growth rate. At the same time, coordination of water transport and growth seemingly should differ between plant functional types. We evaluated the relationships between water transport, growth and species stature in six species of co-occurring trees and shrubs. Within species, a strong proportionality between plant hydraulic conductance (K), sap flow (Q) and shoot biomass growth (G) was generally supported. Across species, however, trees grew more for a given K or Q than shrubs, indicating greater growth-based water-use efficiency (WUE) in trees. Trees also showed slower decline in relative growth rate (RGR) than shrubs, equivalent to a steeper G by mass (M) scaling exponent in trees (0.77-0.98). The K and Q by M scaling exponents were common across all species (0.80, 0.82), suggesting that the steeper G scaling in trees reflects a size-dependent increase in their growth-based WUE. The common K and Q by M exponents were statistically consistent with the 0.75 of ideal scaling theory. A model based upon xylem anatomy and branching architecture consistently predicted the observed K by M scaling exponents but only when deviations from ideal symmetric branching were incorporated.

  9. Coordination between water transport capacity, biomass growth, metabolic scaling and species stature in co-occurring shrub and tree species.

    Science.gov (United States)

    Smith, Duncan D; Sperry, John S

    2014-12-01

    The significance of xylem function and metabolic scaling theory begins from the idea that water transport is strongly coupled to growth rate. At the same time, coordination of water transport and growth seemingly should differ between plant functional types. We evaluated the relationships between water transport, growth and species stature in six species of co-occurring trees and shrubs. Within species, a strong proportionality between plant hydraulic conductance (K), sap flow (Q) and shoot biomass growth (G) was generally supported. Across species, however, trees grew more for a given K or Q than shrubs, indicating greater growth-based water-use efficiency (WUE) in trees. Trees also showed slower decline in relative growth rate (RGR) than shrubs, equivalent to a steeper G by mass (M) scaling exponent in trees (0.77-0.98). The K and Q by M scaling exponents were common across all species (0.80, 0.82), suggesting that the steeper G scaling in trees reflects a size-dependent increase in their growth-based WUE. The common K and Q by M exponents were statistically consistent with the 0.75 of ideal scaling theory. A model based upon xylem anatomy and branching architecture consistently predicted the observed K by M scaling exponents but only when deviations from ideal symmetric branching were incorporated. PMID:25041417

  10. Assessing the potential of native tree species for carbon sequestration forestry in Northeast China.

    Science.gov (United States)

    Thomas, S C; Malczewski, G; Saprunoff, M

    2007-11-01

    Although the native forests of China are exceptionally diverse, only a small number of tree species have been widely utilized in forest plantations and reforestation efforts. We used dendrochronological sampling methods to assess the potential growth and carbon sequestration of native tree species in Jilin Province, Northeast China. Trees were sampled in and near the Changbaishan Biosphere Reserve, with samples encompassing old-growth, disturbed forest, and plantations. To approximate conditions for planted trees, sampling focused on trees with exposed crowns (dominant and co-dominant individuals). A log-linear relationship was found between diameter increment and tree diameter, with a linear decrease in increment with increasing local basal area; no significant differences in these patterns between plantations and natural stands were detected for two commonly planted species (Pinus koraiensis and Larix olgensis). A growth model that incorporates observed feedbacks with individual tree size and local basal area (in conjunction with allometric models for tree biomass), was used to project stand-level biomass increment. Predicted growth trajectories were then linked to the carbon process model InTEC to provide estimates of carbon sequestration potential. Results indicate substantial differences among species, and suggest that certain native hardwoods (in particular Fraxinus mandshurica and Phellodendron amurense), have high potential for use in carbon forestry applications. Increased use of native hardwoods in carbon forestry in China is likely to have additional benefits in terms of economic diversification and enhanced provision of "ecosystem services", including biodiversity protection. PMID:17188419

  11. Species-Level Differences in Hyperspectral Metrics among Tropical Rainforest Trees as Determined by a Tree-Based Classifier

    Directory of Open Access Journals (Sweden)

    Dar A. Roberts

    2012-06-01

    Full Text Available This study explores a method to classify seven tropical rainforest tree species from full-range (400–2,500 nm hyperspectral data acquired at tissue (leaf and bark, pixel and crown scales using laboratory and airborne sensors. Metrics that respond to vegetation chemistry and structure were derived using narrowband indices, derivative- and absorption-based techniques, and spectral mixture analysis. We then used the Random Forests tree-based classifier to discriminate species with minimally-correlated, importance-ranked metrics. At all scales, best overall accuracies were achieved with metrics derived from all four techniques and that targeted chemical and structural properties across the visible to shortwave infrared spectrum (400–2500 nm. For tissue spectra, overall accuracies were 86.8% for leaves, 74.2% for bark, and 84.9% for leaves plus bark. Variation in tissue metrics was best explained by an axis of red absorption related to photosynthetic leaves and an axis distinguishing bark water and other chemical absorption features. Overall accuracies for individual tree crowns were 71.5% for pixel spectra, 70.6% crown-mean spectra, and 87.4% for a pixel-majority technique. At pixel and crown scales, tree structure and phenology at the time of image acquisition were important factors that determined species spectral separability.

  12. 红皮梨新品种高接换种最佳树形的筛选研究%Study on Optimum Tree Canopy Type Selection in High Position Grafted New Red Peeled Pear Cultivars

    Institute of Scientific and Technical Information of China (English)

    申仲妹; 马光跃; 陈红玉; 张金梅

    2011-01-01

    Three tree canopy types, of the modified open centre tree shape, crown canopy and over crown canopy respectively, of high position grafted new red peeled pear cultivars were studied with the method of division in canopy to compare the total scion number, mass growth rate and occupation ratio of scion at all tiers of the three tree canopy types in the growing season. The results showed that the optimum tree canopy type was the modified open centre tree shape after high position grafted new red peeled pear cultivar, in which there were more than 100 scions, shoots mass growth of 53.17 cm and shoots thickness 1.14 cm. For the horizontal, the occupation ratio of the scion was the highest 69.16% between 51 ~ 100 cm. As for the canopy height, the occupation ratio of the scion was 55.14% between 101 ~ 150 cm. The relative light intensity in canopy volume in the modified open centre tree shape was the lowest 36.0%, and the rest parts could accept better light except 0 ~ 50 cm of the horizontal in 50 ~ 100 cm of high position.%红皮梨新品种高接换种采用3种树形,分别为高干开心形、篱壁形、疏散分层形,应用树冠分格方法,在萌芽前对3种树形的接穗总数、不同层次接穗生长量及占有率进行对比研究,并在生长季研究3种树形不同层次相对光照强度的差异.结果表明:高干开心形为红皮梨新品种高接换种最佳树形,该树形接穗总数大于100个,新梢生长量为53.17cm,粗度为1.14cm.从水平位置看,位于51~100cm处接穗占有率最高,为69.16%;从高度位置看,位于101~150cm处接穗占有率为55.14%.相对光照低于30%的占树冠体积空间最小的是高干开心形,为36.0%,高干开心形树体除50~100cm处内膛受光较弱外,其余部位接受光照良好.

  13. Application of Native Tree Species to Urban Forest

    Institute of Scientific and Technical Information of China (English)

    ZHOUZaohong; GUOMeifeng; WUGuoxun

    2004-01-01

    Native trees play important roles in urban forestry, such as a deep cultural background, a strong ecological adaptability, a high performance-cost ratio and a convenient management. But now there are some difficulties in native trees' utilization and popularization due to few study on landscape plant. In order to seek an abnormal and artificial landscaping and to produce an effective result as soon as possible, native and foreign plants can be properly used as an available resource by improving their technological level and emphasizing natural balance. Then Chinese classic culture and green economics can be combined with beautiful forestry by implementing urban sustainable development.

  14. New flux based dose-response relationships for ozone for European forest tree species.

    Science.gov (United States)

    Büker, P; Feng, Z; Uddling, J; Briolat, A; Alonso, R; Braun, S; Elvira, S; Gerosa, G; Karlsson, P E; Le Thiec, D; Marzuoli, R; Mills, G; Oksanen, E; Wieser, G; Wilkinson, M; Emberson, L D

    2015-11-01

    To derive O3 dose-response relationships (DRR) for five European forest trees species and broadleaf deciduous and needleleaf tree plant functional types (PFTs), phytotoxic O3 doses (PODy) were related to biomass reductions. PODy was calculated using a stomatal flux model with a range of cut-off thresholds (y) indicative of varying detoxification capacities. Linear regression analysis showed that DRR for PFT and individual tree species differed in their robustness. A simplified parameterisation of the flux model was tested and showed that for most non-Mediterranean tree species, this simplified model led to similarly robust DRR as compared to a species- and climate region-specific parameterisation. Experimentally induced soil water stress was not found to substantially reduce PODy, mainly due to the short duration of soil water stress periods. This study validates the stomatal O3 flux concept and represents a step forward in predicting O3 damage to forests in a spatially and temporally varying climate.

  15. Herbs versus Trees: Influences on Teenagers' Knowledge of Plant Species

    Science.gov (United States)

    Lückmann, Katrin; Menzel, Susanne

    2014-01-01

    The study reports on species knowledge among German adolescents (n = 507) as: (1) self-assessed evaluation of one's species knowledge; and (2) factual knowledge about popular local herbs and trees. Besides assessing species knowledge, we were interested in whether selected demographic factors, environmental attitude (as measured through the…

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

    Directory of Open Access Journals (Sweden)

    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.

  17. Species-specific Variation in the Importance of the Spectral Quality Gradient in Canopies as a Signal for Photosynthetic Resource Partitioning

    OpenAIRE

    Pons, Thijs L.; de JONG-VAN BERKEL, YVONNE E. M.

    2004-01-01

    • Background and Aims Plants adjust the distribution of photosynthetic capacity and chlorophyll to canopy density. The importance of the gradient in the red : far-red ratio (R : FR) relative to the irradiance gradient was studied for its perception with respect to this partitioning of photosynthetic resources. Whether the relative importance of these two signals varied between six species of different growth habit (Phaseolus vulgaris, Lysimachia vulgaris, Hedera helix, Ficus benjamina, Carex ...

  18. The Silvics of Some East European and Siberian Boreal Forest Tree Species

    OpenAIRE

    Korzukin, M.D.; Rubinina, A.E.; G. B. Bonan; Solomon, A.M.; Antonovsky, M.Y.

    1989-01-01

    In recent years, the boreal forest has received increased scientific attention in light of projected climatic warming to boreal regions from increased concentrations of atmospheric carbon dioxide. The ecological consequences of such a warming could be significant. However, before the consequences of climatic change can be properly investigated, the ecology of boreal forest tree species must be adequately understood. Though the life-histories of many North American boreal forest tree species a...

  19. Demography of exploited tree species in the Bolivian Amazon

    NARCIS (Netherlands)

    Zuidema, P.A.

    2001-01-01

    Tropical forests are threatened world-wide. Therefore, there is a search for ways to use the forests in a sustainable way, as this could assist in the conservation of these special ecosystems. Non-timber products collected from trees in tropical forests are often mentioned as examples of sustaina

  20. Architecture of 54 moist-forest species: traits, trade-offs, and functional groups

    NARCIS (Netherlands)

    Poorter, L.; Bongers, L.; Bongers, F.J.J.M.

    2006-01-01

    Tree architecture is an important determinant of the height extension, light capture, and mechanical stability of trees, and it allows species to exploit the vertical height gradient in the forest canopy and horizontal light gradients at the forest floor. Tropical tree species partition these gradie

  1. Tree species diversity in the Eastern Ghats of northern Andhra Pradesh, India

    Directory of Open Access Journals (Sweden)

    M. Tarakeswara Naidu

    2015-06-01

    Full Text Available The present study was conducted to analyze tree species diversity in the tropical forests of the Eastern Ghats of northern Andhra Pradesh, India.  A total of 270 species of trees (≥15cm girth at breast height pertaining to 177 genera belonging to 55 families were recorded.  Among the 270 species, 141 species were observed to be common, 78 were occasional and 51 species were rare in the study area.  Fabaceae was the dominant family with 33 species followed by Rubiaceae with 15 species and Malvaceae, Moraceae and Phyllanthaceae with 13 species each.  The genera with the highest number of species include Ficus (12 species, Diospyros (8 species, Albizia and Grewia (6 species each, Acacia and Bauhinia (5 species each.  Forty-five percent of the species were indigenous. This illustrates the diversity of the tree species in the studied area of the Eastern Ghats and also emphasizes the need for their conservation. 

  2. The natural abundance of 15N in litter and soil profiles under six temperate tree species: N cycling depends on tree species traits and site fertility

    DEFF Research Database (Denmark)

    Callesen, Ingeborg; Nilsson, Lars Ola; Schmidt, Inger Kappel;

    2013-01-01

    for these N variables and for the litter δ15N and enrichment factor. Litter from ash and sycamore maple with high N status and low fungal mycelia activity was enriched in 15N (+0.9 delta units) relative to other tree species (European beech, pedunculate oak, lime and Norway spruce) even though the latter...

  3. Inter- and intra-specific variation in stemflow for evergreen species and deciduous tree species in a subtropical forest

    Science.gov (United States)

    Su, Lei; Xu, Wenting; Zhao, Changming; Xie, Zongqiang; Ju, Hua

    2016-06-01

    Quantification of stemflow is necessary for the assessment of forest ecosystem hydrological effects. Nevertheless, variation of stemflow among plant functional groups is currently not well understood. Stemflow production of co-occurring evergreen broadleaved trees (Cyclobalanopsis multinervis and Cyclobalanopsis oxyodon) and deciduous broadleaved trees (Fagus engleriana and Quercus serrata var. brevipetiolata) was quantified through field observations in a mixed evergreen and deciduous broadleaved forest. The research results revealed that stemflow increased linearly with increasing rainfall magnitude, with precipitation depths of 6.9, 7.2, 10.0 and 14.8 mm required for the initiation of stemflow for C. multinervis, C. oxyodon, F. engleriana and Q. serrata, respectively. Stemflow percentage and funneling ratio (FR) increased with increasing rainfall in a logarithmic fashion. Stemflow percentage and FR tended to grow rapidly with increasing rainfall magnitude up to a rainfall threshold of 50 mm, above which, further rainfall increases brought about only small increases. For C. multinervis, C. oxyodon, F. engleriana and Q. serrata, FR averaged 19.8, 14.8, 8.9 and 2.8, respectively. The stemflow generating rainfall thresholds for evergreen species were smaller than for deciduous species. Furthermore, stemflow percentage and FR of the former was greater than the latter. For both evergreen species and deciduous species, overall funneling ratio (FRs) decreased with increasing basal area. We concluded that: (1) although stemflow partitioning represented a fairly low percentage of gross rainfall in mixed evergreen and deciduous broadleaved forests, it was capable of providing substantial amount of rainwater to tree boles; (2) the evergreen species were more likely to generate stemflow than deciduous species, and directed more intercepted rainwater to the root zone; (3) small trees were more productive in funneling stemflow than larger trees, which may provide a favorable

  4. Tree Species and Their Space Requirements in Six Urban Environments Worldwide

    Directory of Open Access Journals (Sweden)

    Jens Dahlhausen

    2016-05-01

    Full Text Available Urban trees have gained in importance during recent decades, but little is known about the temporal dynamic of tree growth in urban areas. The present study investigated the allometric relationships of stem diameter, tree height, and crown radius for six different tree species in six metropolises worldwide. Increment cores of the trees were used for identifying the relationship of basal area and basal area increment and for extrapolating the temporal dynamics for each species in relation to the allometric parameters and growth extensions. Space limitation and its direct influence on growth were quantified, as well as the aboveground woody biomass and the carbon storage capacity. The results show that, among the investigated species, Quercus nigra and Khaya senegalensis have the highest growth rates for stem diameter and crown radius, whereas Tilia cordata and Aesculus hippocastanum remain on a lower level. A significant reduction of tree growth due to restricted non-paved area was found for Aesculus hippocastanum and Khaya senegalensis. Estimations of aboveground biomass were highest for Quercus nigra and lowest for Tilia cordata. These results show the species-specific allometries of urban trees over a projected time period. Thus, the data set is highly relevant for planners and urban green managers.

  5. Do ectomycorrhizal and arbuscular mycorrhizal temperate tree species systematically differ in root order-related fine root morphology and biomass?

    OpenAIRE

    Kubisch, Petra; Hertel, Dietrich; Leuschner, Christoph

    2015-01-01

    While most temperate broad-leaved tree species form ectomycorrhizal (EM) symbioses, a few species have arbuscular mycorrhizas (AM). It is not known whether EM and AM tree species differ systematically with respect to fine root morphology, fine root system size and root functioning. In a species-rich temperate mixed forest, we studied the fine root morphology and biomass of three EM and three AM tree species from the genera Acer, Carpinus, Fagus, Fraxinus, and Tilia searching for principal dif...

  6. Tree species traits influence soil physical, chemical, and biological properties in high elevation forests.

    Directory of Open Access Journals (Sweden)

    Edward Ayres

    Full Text Available BACKGROUND: Previous studies have shown that plants often have species-specific effects on soil properties. In high elevation forests in the Southern Rocky Mountains, North America, areas that are dominated by a single tree species are often adjacent to areas dominated by another tree species. Here, we assessed soil properties beneath adjacent stands of trembling aspen, lodgepole pine, and Engelmann spruce, which are dominant tree species in this region and are distributed widely in North America. We hypothesized that soil properties would differ among stands dominated by different tree species and expected that aspen stands would have higher soil temperatures due to their open structure, which, combined with higher quality litter, would result in increased soil respiration rates, nitrogen availability, and microbial biomass, and differences in soil faunal community composition. METHODOLOGY/PRINCIPAL FINDINGS: We assessed soil physical, chemical, and biological properties at four sites where stands of aspen, pine, and spruce occurred in close proximity to one-another in the San Juan Mountains, Colorado. Leaf litter quality differed among the tree species, with the highest nitrogen (N concentration and lowest lignin:N in aspen litter. Nitrogen concentration was similar in pine and spruce litter, but lignin:N was highest in pine litter. Soil temperature and moisture were highest in aspen stands, which, in combination with higher litter quality, probably contributed to faster soil respiration rates from stands of aspen. Soil carbon and N content, ammonium concentration, and microbial biomass did not differ among tree species, but nitrate concentration was highest in aspen soil and lowest in spruce soil. In addition, soil fungal, bacterial, and nematode community composition and rotifer, collembolan, and mesostigmatid mite abundance differed among the tree species, while the total abundance of nematodes, tardigrades, oribatid mites, and prostigmatid

  7. Seedling transplants reveal species-specific responses of high-elevation tropical treeline trees to climate change.

    Science.gov (United States)

    Rehm, Evan M; Feeley, Kenneth J

    2016-08-01

    The elevations at which tropical treelines occur are believed to represent the point where low mean temperatures limit the growth of upright woody trees. Consequently, tropical treelines are predicted to shift to higher elevations with global warming. However, treelines throughout the tropics have remained stationary despite increasing global mean temperatures. The goal of the study reported here was to build a more comprehensive understanding of the effects of mean temperature, low-temperature extremes, shading, and their interactions on seedling survival at tropical treelines. We conducted a seedling transplant study using three dominant canopy-forming treeline species in the southern tropical Andes. We found species-specific differences and contrasting responses in seedling survival to changes in mean temperature. The most abundant naturally occurring species at the seedling stage outside the treeline, Weinmannia fagaroides, showed a negative relationship between the survival of transplanted seedlings and mean temperature, the opposite of a priori expectations. Conversely, Clethra cuneata showed increased survival at higher mean temperatures, but survival also increased with higher absolute low temperatures and the presence of shade. Finally, the survival of Gynoxys nitida seedlings was insensitive to temperature but increased under shade. These findings show that multiple factors can determine the upper distributional limit of species forming the current tropical treeline. As such, predictions of future local and regional tropical treeline shifts may need to consider several factors beyond changes in mean temperature. If the treeline remains stationary and cloud forests are unable to expand into higher elevations, there may be severe species loss in this biodiversity hotspot. PMID:27071667

  8. Seasonal and yearly variations in light use and nitrogen use by seedlings of four deciduous broad-leaved tree species invading larch plantations.

    Science.gov (United States)

    Kitaoka, Satoshi; Koike, Takayoshi

    2005-04-01

    Several deciduous broad-leaved tree species, differing in leaf phenology, invade larch (Larix kaempferii (Lamb.) Carrière) plantations in Japan. The understory light environment of larch forests changes drastically between the leafy and leafless periods. To determine how the invading seedlings exploit the changing light environment, and if phenological differences reflect the light- and nitrogen-use traits of the seedlings, we measured leaf phenology, seasonal changes in light-saturated photosynthetic rate (P(sat)), leaf nitrogen (N) content (N(area)), chlorophyll/nitrogen ratio (Chl/N), specific leaf area (SLA) and N remobilization rate (NRMR) over 3 years. The mid-successional or gap-phase species, Magnolia hypoleuca Siebold & Zucc., had a short leafy period and high P(sat) and NRMR. In contrast, two late-successional tree species, Prunus ssiori Friedr. Schmidt, which undergoes leaf flush before larch, and Carpinus cordata Blume, which maintains green leaves until frost, both had low P(sat) and NRMR but exploited the opportunity for growth during the period when the larch canopy trees were leafless. Quercus mongolica Fisch. ex Ledeb. var. crispula (Blume) Ohashi, a mid-late-successional species that underwent leaf flush at the same time as the overstory larch, had values of photosynthetic parameters between those of the gap-phase and late-successional species. Among species, M. hypoleuca and Q. mongolica had higher photosynthetic rates and photosynthetic N-use efficiencies. In all species, the relationship between N(area) and P(sat) showed species-specific yearly fluctuations; however, there was no yearly fluctuation in the relationship between N(area) and P(sat) at CO2 saturation. Yearly fluctuations in the N(area)-P(sat) relationship appeared to be induced by changes in SLA and N-use characteristics, which in turn are affected by climatic variations.

  9. Water consumption of a single tree from the main afforestation tree species in Western Shanxi Province, a loess area

    Institute of Scientific and Technical Information of China (English)

    Xiaoming ZHANG; Xinxiao YU; Wenhong CAO; Huifang LIU

    2008-01-01

    Water is the key factor in vegetation growth in a loess area. Researchers have been keen on the study of tree transpiration for a long time. To provide a scientific basis and practical instruction for vegetation reconstruction and recovery in a loess area, the paper measured and calculated the water consumption of potted Platycladus orientalis, Robinia pseudoacacia, Armeniaca vulgaris and Pyrus hopeiensis separately during the growing season (from Apr. to Nov,). The four were the main afforestation species in a loess area of western Shanxi based on the principle of water balance. Using data on soil water dynamics and the range of available moisture on potted mature trees, the relationship between water supply and consumption and soil moisture availability and deficit state were analyzed. Several conclusions are listed as follows: 1) In the dry year (2002), during the growing season the precipitation was 430.7 mm and the water consumption of potted trees was from 430 to 490 mm. More water consumption and less available water supply occurred, showing a serious water deficiency. In the rainfall-rich year (2003), during the growing season the precipitation was 870.2 mm and the water consumption of potted trees was from 480 to 515 mm. Due to the uneven distribution of rainfall, the water budget balance was slightly affected in May and November. 2) The curves of soil water content of different species had similar annual changes, although the trends were different in the same month, and those of the same tree species in different test plots also had different trends in the same month. 3) Non-available soil water content of Platycladus orien-talis, Robinia pseudoacacia, Armeniaca vulgaris and Pyrus hopeiensis was less than 8.0%, 8.4%, 9.2% and 9.7% respectively, which indicated that Pyrus orentalis used water more efficiently than the others. In the dry year (2002), for several months, soil water content of potted trees was lower than its threshold value for non

  10. Ecological impact of Prosopis species invasion in Turkwel riverine forest, Kenya

    NARCIS (Netherlands)

    Muturi, G.M.; Poorter, L.; Mohren, G.M.J.; Kigomo, B.N.

    2013-01-01

    The impact of Prosopis species invasion in the Turkwel riverine forest in Kenya was investigated under three contrasting: Acacia, Prosopis and Mixed species (Acacia and Prosopis) canopies. Variation amongst canopies was assessed through soil nutrients and physical properties, tree characteristics an

  11. Temporal and Spatial Dynamics of Tree Species Composition in Temperate Mountains of South Korea

    Science.gov (United States)

    Lee, Boknam; Park, Juhan; Cho, Sungsik; Ryu, Daun; Zaw Wynn, Khine; Park, Minji; Cho, Sunhee; Yoon, Jongguk; Park, Jongyoung; Kim, Hyun Seok

    2015-04-01

    Long term studies on vegetation dynamics are important to identify changes of ecosystem-level responses to climate change. To learn how tree species composition and stand structure change across temperate mountains, the temporal and spatial variations in tree species diversity and structure were investigated using the species composition and DBH size collected over the fourteen-year period across 134 sites in Jiri and Baekoon Mountains, South Korea. The overall temporal changes over fourteen years showed significant increase in stand density, species diversity and evenness according to the indices of Shannon-Weiner diversity, Bray-Curtis dissimilarity, and Pielou's evenness, contributing to the increase of basal area and biomass growth. The change of tree species composition could be categorized into five species communities, representing gradual increase or decrease, establishment, extinction, fluctuation of species population. However, in general, the change in species composition appeared to have consistent and directional patterns of increase in the annual rate of change in the mean species traits including species richness, pole growth rate, adult growth rate, and adult stature with five common dominant species (Quercus mongolica, Quercus variabilis, Quercus serrata, Carpinus laxiflora, and Styrax japonicus). The spatial patterns of species composition appeared to have a higher stand density and species diversity along with the low latitude and high slope ecosystem. The climate change was another main driver to vary the distribution of species abundance. Overall, both temporal and spatial changes of composition in tree species community was clear and further analysis to clarify the reasons for such fast and species-specific changes is underway especially to separate the effect of successional change and climate change. Keywords species composition; climate change; temporal and spatial variation ; forest structure; temperate forest

  12. [Effects of sampling plot number on tree species distribution prediction under climate change].

    Science.gov (United States)

    Liang, Yu; He, Hong-Shi; Wu, Zhi-Wei; Li, Xiao-Na; Luo, Xu

    2013-05-01

    Based on the neutral landscapes under different degrees of landscape fragmentation, this paper studied the effects of sampling plot number on the prediction of tree species distribution at landscape scale under climate change. The tree species distribution was predicted by the coupled modeling approach which linked an ecosystem process model with a forest landscape model, and three contingent scenarios and one reference scenario of sampling plot numbers were assumed. The differences between the three scenarios and the reference scenario under different degrees of landscape fragmentation were tested. The results indicated that the effects of sampling plot number on the prediction of tree species distribution depended on the tree species life history attributes. For the generalist species, the prediction of their distribution at landscape scale needed more plots. Except for the extreme specialist, landscape fragmentation degree also affected the effects of sampling plot number on the prediction. With the increase of simulation period, the effects of sampling plot number on the prediction of tree species distribution at landscape scale could be changed. For generalist species, more plots are needed for the long-term simulation.

  13. Carbon and Nitrogen dynamics in forest soils depending on light conditions and tree species

    Science.gov (United States)

    Veselinovic, Bojana; Hager, Herbert

    2013-04-01

    Climate change mitigation actions under the Kyoto Protocol apply among other decreases of CO2-emissions and/or increases of carbon (C) stocks. As soils represent the second biggest C-reservoir on Earth, an exact estimation of the stocks and reliable knowledge on C-dynamics in forest soils is of high importance. Anyhow, here, the accurate GHG-accounting, emission reductions and increase in C stocks is hampered due to lack of reliable data and solid statistical methods for the factors which influence C-sequestration in and its release from these systems. In spite of good progress in the scientific research, these factors are numerous and diverse in their interactions. This work focuses on influence of the economically relevant tree species - Picea abies, Fagus sylvatica and Quercus spp. - and light conditions on forest floor and mineral soil C and N dynamics in forest soils. Spruce monocultures have been widely used management practices in central European forests during the past century. Such stands are in lower altitudes and on heavy and water logged soils unstable and prone to disturbances, especially to windthrows. We hypothesize that windthrow areas loose C & N and that the establishment of the previous nutrient stocks is, if at all, only possible to be reached over the longer periods of time. We research also how the increased OM depletion affects the change of C & N stocks in forest floor vs. mineral soil. Conversion of such secondary spruce monocultures to site adequate beech and oak forests may enable higher stocks allocated predominantly as stable organic carbon and as plant available nitrogen. For this purpose sites at 300-700 m altitude with planosols were chosen in the region of the Northern Alpine Foothills. A false chronosequence approach was used in order to evaluate the impacts of the tree species and change in light conditions on dynamic of C & N in the forest floor and mineral soil, over the period 0-100 (for oak 120 y.) years. The C- and N

  14. Quantification of potential lignocellulosic biomass in fruit trees grown in Mediterranean regions

    Directory of Open Access Journals (Sweden)

    Harald Fernández-Puratich

    2013-02-01

    Full Text Available This research was based on three species: Citrus sinensis (orange, Olea europaea (olive, and Prunus amygdalus (almond. The biomass was determined for a complete tree without roots, but including stem, branches, and canopy or crown. The obtained results demonstrate that the stem volume is slightly higher for almond trees (0.035 m3/tree than for olive trees (0.027 m3/tree. In comparison, the average stem volume of orange trees is lower (0.006 m3/tree. On the other hand, the total biomass volume including canopy branches is similar in all three species: 0.043 m3/tree for orange tree, 0.066 m3/tree for olive tree, and 0.040 m3/tree for almond tree. The new practical quantification model for these Mediterranean agricultural crops is based on total biomass calculations normally used in forestry stands. So, the obtained values were used to develop models for biomass of the stem, branches, and canopy, relating them with the diameter and volume stem. The regression analysis shows a significant correlation with minimized estimation errors. This allows a practical use of this model in biomass calculation in standing trees, both for total tree biomass and also for pruning material.

  15. Experimental canopy removal enhances diversity of vernal pond amphibians.

    Science.gov (United States)

    Skelly, David K; Bolden, Susan R; Freidenburg, L Kealoha

    2014-03-01

    Vernal ponds are often treated as protected environments receiving special regulation and management. Within the landscapes where they are found, forest vegetation frequently dominates surrounding uplands and can grow to overtop and shade pond basins. Two bodies of research offer differing views of the role of forest canopy for vernal pond systems. Studies of landscape conversion suggest that removing forest overstory within uplands can cause local extinctions of amphibians by altering terrestrial habitat or hindering movement. Studies of canopy above pond basins imply an opposite relationship; encroachment of overstory vegetation can be associated with local extinctions potentially via changes in light, thermal, and food resource environments. Unresolved uncertainties about the role of forest canopy reveal significant gaps in our understanding of wetland species distributions and dynamics. Any misunderstanding of canopy influences is simultaneously important to managers because current practices emphasize promoting or conserving vegetation growth particularly within buffers immediately adjacent to ponds. We evaluated this apparent contradiction by conducting a landscape-scale, long-term experiment using 14 natural vernal ponds. Tree felling at six manipulated ponds was limited in spatial scope but was nevertheless effective in increasing water temperature. Compared with eight control ponds, manipulated ponds maintained more amphibian species during five years post-manipulation. There was little evidence that any species was negatively influenced, and the reproductive effort of species for which we estimated egg inputs maintained pretreatment population densities in manipulated compared with control ponds. Overall, our experiment shows that a carefully circumscribed reduction of overhead forest canopy can enhance the capacity of vernal ponds to support wildlife diversity and suggests a scale dependence of canopy influences on amphibians. These findings have

  16. Experimental canopy removal enhances diversity of vernal pond amphibians.

    Science.gov (United States)

    Skelly, David K; Bolden, Susan R; Freidenburg, L Kealoha

    2014-03-01

    Vernal ponds are often treated as protected environments receiving special regulation and management. Within the landscapes where they are found, forest vegetation frequently dominates surrounding uplands and can grow to overtop and shade pond basins. Two bodies of research offer differing views of the role of forest canopy for vernal pond systems. Studies of landscape conversion suggest that removing forest overstory within uplands can cause local extinctions of amphibians by altering terrestrial habitat or hindering movement. Studies of canopy above pond basins imply an opposite relationship; encroachment of overstory vegetation can be associated with local extinctions potentially via changes in light, thermal, and food resource environments. Unresolved uncertainties about the role of forest canopy reveal significant gaps in our understanding of wetland species distributions and dynamics. Any misunderstanding of canopy influences is simultaneously important to managers because current practices emphasize promoting or conserving vegetation growth particularly within buffers immediately adjacent to ponds. We evaluated this apparent contradiction by conducting a landscape-scale, long-term experiment using 14 natural vernal ponds. Tree felling at six manipulated ponds was limited in spatial scope but was nevertheless effective in increasing water temperature. Compared with eight control ponds, manipulated ponds maintained more amphibian species during five years post-manipulation. There was little evidence that any species was negatively influenced, and the reproductive effort of species for which we estimated egg inputs maintained pretreatment population densities in manipulated compared with control ponds. Overall, our experiment shows that a carefully circumscribed reduction of overhead forest canopy can enhance the capacity of vernal ponds to support wildlife diversity and suggests a scale dependence of canopy influences on amphibians. These findings have

  17. Evolutionary patterns of range size, abundance and species richness in Amazonian angiosperm trees

    Science.gov (United States)

    Chave, Jérôme

    2016-01-01

    Amazonian tree species vary enormously in their total abundance and range size, while Amazonian tree genera vary greatly in species richness. The drivers of this variation are not well understood. Here, we construct a phylogenetic hypothesis that represents half of Amazonian tree genera in order to contribute to explaining the variation. We find several clear, broad-scale patterns. Firstly, there is significant phylogenetic signal for all three characteristics; closely related genera tend to have similar numbers of species and similar mean range size and abundance. Additionally, the species richness of genera shows a significant, negative relationship with the mean range size and abundance of their constituent species. Our results suggest that phylogenetically correlated intrinsic factors, namely traits of the genera themselves, shape among lineage variation in range size, abundance and species richness. We postulate that tree stature may be one particularly relevant trait. However, other traits may also be relevant, and our study reinforces the need for ambitious compilations of trait data for Amazonian trees. In the meantime, our study shows how large-scale phylogenies can help to elucidate, and contribute to explaining, macroecological and macroevolutionary patterns in hyperdiverse, yet poorly understood regions like the Amazon Basin. PMID:27651991

  18. Comparative locomotor ecology of gibbons and macaques: selection of canopy elements for crossing gaps.

    Science.gov (United States)

    Cannon, C H; Leighton, M

    1994-04-01

    To examine functional questions of arboreal locomotor ecology, the selection of canopy elements by Bornean agile gibbons (Hylobates agilis) and long-tailed macaques (Macaca fascicularis) was contrasted, and related to locomotor behaviors. The two species, and in some cases, the macaque sexes, varied in their use of most structural elements. Although both species traveled most frequently in the main canopy layer (macaques: 56%, gibbons: 48%), the gibbons strongly preferred the emergent canopy layer and traveled higher than the macaques (31 vs. 23 m above ground) in larger trees (48 vs. 26 cm dbh). Macaques preferred to cross narrower gaps (50% were in the class 0.1-0.5 m wide) than gibbons (42% were 1.6-3.0 m wide), consistent with the maximum gap width each crossed (3.5 m for macaques, 9 m for gibbons). Macaques could cross only 12% of the gaps encountered in the main canopy, and < 5% of the gaps in each of the other four layers. In contrast, all layers appear relatively continuous for gibbons. Specialized locomotor modes were used disproportionately at the beginning and end of travel segments, further indicating that behavior was organized around gap crossings. A model is defined, the Perceived Continuity Index (PCI), which predicts the relative use of canopy strata for each species, based on the percentage of gaps a species can cross, the frequency of gaps, and median length of continuous canopy structure in each canopy layer. The results support the hypothesis that locomotor behaviors, and strategies of selecting canopy strata for travel, are strongly constrained by wide gaps between trees and are ultimately based on selection for efficient direct line travel between distant points. PMID:8048471

  19. Ambrosia Beetle (Coleoptera: Scolytidae) Species, Flight, and Attack on Living Eastern Cottonwood Trees.

    Energy Technology Data Exchange (ETDEWEB)

    Coyle, D R; D.C. Booth: M.S. Wallace

    2005-12-01

    ABSTRACT In spring 2002, ambrosia beetles (Coleoptera: Scolytidae) infested an intensively managed 22-ha tree plantation on the upper coastal plain of South Carolina. Nearly 3,500 scolytids representing 28 species were captured in ethanol-baited traps from 18 June 2002 to 18 April 2004. More than 88% of total captures were exotic species. Five species [Dryoxylon onoharaensum (Murayama), Euwallacea validus (Eichhoff), Pseudopityophthorus minutissimus (Zimmermann), Xyleborus atratus Eichhoff, and Xyleborus impressus Eichhoff]) were collected in South Carolina for the first time. Of four tree species in the plantation, eastern cottonwood, Populus deltoides Bartram, was the only one attacked, with nearly 40% of the trees sustaining ambrosia beetle damage. Clone ST66 sustained more damage than clone S7C15. ST66 trees receiving fertilization were attacked more frequently than trees receiving irrigation, irrigation_fertilization, or controls, although the number of S7C15 trees attacked did not differ among treatments. The study location is near major shipping ports; our results demonstrate the necessity for intensive monitoring programs to determine the arrival, spread, ecology, and impact of exotic scolytids.

  20. Effect of tree species and soil properties on nutrient immobilization in the forest floor

    DEFF Research Database (Denmark)

    Raulund-Rasmussen, Karsten; Vejre, Henrik

    1995-01-01

    To investigate the effect of tree species and soil properties on organic matter accumulation and associated nutrients, an area-based sampling of the forest floor was carried out in a 28 years old species trial including Norway spruce, Douglas fir, beech, and common oak at two sites, a poor and sa...

  1. Spatial distributions of tropical tree species in northern Vietnam under environmentally variable site conditions

    Institute of Scientific and Technical Information of China (English)

    Nguyen Hong Hai; Kerstin Wiegand; Stephan Getzin

    2014-01-01

    Ecological interactions of species and thus their spatial pat-terns may differ between homogeneous and heterogeneous forests. To account for this, techniques of point pattern analysis were implemented on mapped locations of tree individuals from two 1-ha tropicalforest plots in Vietnam. We analyzed the effect of environmental heterogeneity on tree distributions; spatial distribution patterns of dominant species;inter-specific associations; and conspecific associations between life stages. Our analyses showed that:environmental conditions were homo-geneous at plot 1 but heterogeneous at plot 2;in both plots, all six domi-nant species were aggregated at various scales up to 30 m, and tree spe-cies were aggregated at larger scales in the homogeneous site than in the heterogeneous site; attraction between pairs of species was remarkably higher at the homogeneous site while negative associations were more frequent in the heterogeneous site; some species, H. kurzii, T. ilicifolia (homogeneous plot) and D. sylvatica, S. wightianum (heterogeneous plot), showed a lack of early life-stage individuals near conspecific adults. Moreover, additional clustering of young individuals was independent from conspecific adults, except D. sylvatica in both sites. These findings are consistent with the Janzen-Connell hypothesis. Overall, habitat het-erogeneity influences spatial patterns and inter-specific associations of the tree species and evidences of self-thinning are shown in most species.

  2. Barriopsis iraniana and Phaeobotryon cupressi: two new species of the Botryosphaeriaceae from trees in Iran

    NARCIS (Netherlands)

    Abdollahzadeh, J.; Mohammadi Goltapeh, E.; Javadi, A.; Shams-bakhsh, M.; Zare, R.; Phillips:, A.J.L.

    2009-01-01

    Species in the Botryosphaeriaceae are well known as pathogens and saprobes of woody hosts, but little is known about the species that occur in Iran. In a recent survey of this family in Iran two fungi with diplodia-like anamorphs were isolated from various tree hosts. These two fungi were fully char

  3. Selective logging in tropical forests decreases the robustness of liana-tree interaction networks to the loss of host tree species.

    Science.gov (United States)

    Magrach, Ainhoa; Senior, Rebecca A; Rogers, Andrew; Nurdin, Deddy; Benedick, Suzan; Laurance, William F; Santamaria, Luis; Edwards, David P

    2016-03-16

    Selective logging is one of the major drivers of tropical forest degradation, causing important shifts in species composition. Whether such changes modify interactions between species and the networks in which they are embedded remain fundamental questions to assess the 'health' and ecosystem functionality of logged forests. We focus on interactions between lianas and their tree hosts within primary and selectively logged forests in the biodiversity hotspot of Malaysian Borneo. We found that lianas were more abundant, had higher species richness, and different species compositions in logged than in primary forests. Logged forests showed heavier liana loads disparately affecting slow-growing tree species, which could exacerbate the loss of timber value and carbon storage already associated with logging. Moreover, simulation scenarios of host tree local species loss indicated that logging might decrease the robustness of liana-tree interaction networks if heavily infested trees (i.e. the most connected ones) were more likely to disappear. This effect is partially mitigated in the short term by the colonization of host trees by a greater diversity of liana species within logged forests, yet this might not compensate for the loss of preferred tree hosts in the long term. As a consequence, species interaction networks may show a lagged response to disturbance, which may trigger sudden collapses in species richness and ecosystem function in response to additional disturbances, representing a new type of 'extinction debt'.

  4. Selective logging in tropical forests decreases the robustness of liana-tree interaction networks to the loss of host tree species.

    Science.gov (United States)

    Magrach, Ainhoa; Senior, Rebecca A; Rogers, Andrew; Nurdin, Deddy; Benedick, Suzan; Laurance, William F; Santamaria, Luis; Edwards, David P

    2016-03-16

    Selective logging is one of the major drivers of tropical forest degradation, causing important shifts in species composition. Whether such changes modify interactions between species and the networks in which they are embedded remain fundamental questions to assess the 'health' and ecosystem functionality of logged forests. We focus on interactions between lianas and their tree hosts within primary and selectively logged forests in the biodiversity hotspot of Malaysian Borneo. We found that lianas were more abundant, had higher species richness, and different species compositions in logged than in primary forests. Logged forests showed heavier liana loads disparately affecting slow-growing tree species, which could exacerbate the loss of timber value and carbon storage already associated with logging. Moreover, simulation scenarios of host tree local species loss indicated that logging might decrease the robustness of liana-tree interaction networks if heavily infested trees (i.e. the most connected ones) were more likely to disappear. This effect is partially mitigated in the short term by the colonization of host trees by a greater diversity of liana species within logged forests, yet this might not compensate for the loss of preferred tree hosts in the long term. As a consequence, species interaction networks may show a lagged response to disturbance, which may trigger sudden collapses in species richness and ecosystem function in response to additional disturbances, representing a new type of 'extinction debt'. PMID:26936241

  5. Comparative measurements of transpiration an canopy conductance in two mixed deciduous woodlands differing in structure and species composition

    DEFF Research Database (Denmark)

    Herbst, Mathias; Rosier, Paul T.W.; Morecroft, Michael D.;

    2008-01-01

    a continuous hazel (Corylus avellana L.) understory. Wytham Woods, which had an LAI of 3.6, was dominated by ash (Fraxinus excelsior L.) and sycamore (Acer pseudoplatanus L.) and had only a sparse understory. Annual canopy transpiration was 367 mm for Grimsbury Wood and 397 mm for Wytham Woods. These values...

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

    Directory of Open Access Journals (Sweden)

    Guoyu Lan

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

  7. Rhizosphere soil microbial index of tree species in a coal mining ecosystem

    Energy Technology Data Exchange (ETDEWEB)

    Sinha, S.; Masto, R.E.; Ram, L.C.; Selvi, V.A.; Srivastava, N.K.; Tripathi, R.C.; George, J. [Central Institute of Mining & Fuel Research, Dhanbad (India)

    2009-09-15

    Microbial characterization of the tree rhizosphere provides important information relating to the screening of tree species for re-vegetation of degraded land. Rhizosphere soil samples collected from a few predominant tree species growing in the coal mining ecosystem of Dhanbad, India, were analyzed for soil organic carbon (SOC), mineralizable N, microbial biomass carbon (MBC), active microbial biomass carbon (AMBC), basal soil respiration (BSR), and soil enzyme activities (dehydrogenase, urease, catalase, phenol oxidase, and peroxidase). Principal component analysis was employed to derive a rhizosphere soil microbial index (RSMI) and accordingly, dehydrogenase, BSR/MBC, MBC/SOC, EC, phenol oxidase and AMBC were found to be the most critical properties. The observed values for the above properties were converted into a unitless score (0-1.00) and the scores were integrated into RSMI. The tree species could be arranged in decreasing order of the RSMI as: A. marmelos (0.718), A. indica (0.715), Bauhinia bauhinia (0.693), B. monosperma (0.611), E. jambolana (0.601), Moringa oleifera (0.565), Dalbergia sissoo (0.498), T indica (0.488), Morus alba (0.415), F religiosa (0.291), Eucalyptus sp. (0.232) and T grandis (0.181). It was concluded that tree species in coal mining areas had diverse effects on their respective rhizosphere microbial processes, which could directly or indirectly determine the survival and performance of the planted tree species in degraded coal mining areas. Tree species with higher RSMI values could be recommended for re-vegetation of degraded coal mining area.

  8. Early establishment of trees at the alpine treeline: idiosyncratic species responses to temperature-moisture interactions.

    Science.gov (United States)

    Loranger, Hannah; Zotz, Gerhard; Bader, Maaike Y

    2016-01-01

    On a global scale, temperature is the main determinant of arctic and alpine treeline position. However on a local scale, treeline form and position vary considerably due to other climatic factors, tree species ecology and life-stage-dependent responses. For treelines to advance poleward or uphill, the first steps are germination and seedling establishment. These earliest life stages may be major bottlenecks for treeline tree populations and will depend differently on climatic conditions than adult trees. We investigated the effect of soil temperature and moisture on germination and early seedling survival in a field experiment in the French Alps near the local treeline (2100 m a.s.l.) using passive temperature manipulations and two watering regimes. Five European treeline tree species were studied: Larix decidua, Picea abies, Pinus cembra, Pinus uncinata and Sorbus aucuparia In addition, we monitored the germination response of three of these species to low temperatures under controlled conditions in growth chambers. The early establishment of these trees at the alpine treeline was limited either by temperature or by moisture, the sensitivity to one factor often depending on the intensity of the other. The results showed that the relative importance of the two factors and the direction of the effects are highly species-specific, while both factors tend to have consistent effects on both germination and early seedling survival within each species. We show that temperature and water availability are both important contributors to establishment patterns of treeline trees and hence to species-specific forms and positions of alpine treelines. The observed idiosyncratic species responses highlight the need for studies including several species and life-stages to create predictive power concerning future treeline dynamics. PMID:27402618

  9. Vegetative and reproductive phenology of a floodplain tree species Barringtonia acutangula from North East India.

    Science.gov (United States)

    Nath, Shikhasmita; Nath, Arun Jyoti; Das, Ashesh Kumar

    2016-03-01

    Vegetative and reproductive phenology of Barringtonia acutangula, a floodplain tree species was studied at Chatla floodplain, Assam North East India with the aim to investigate vegetative and reproductive phenology under stressful environment of seasonal submergence and to assess the impact of environmental variables (temperature and precipitation) on tree phenophases. Quantitative assessment was made at 15 day interval for all the phenophases (leaf initiation, leaf-fall, flowering and fruiting) by tagging 40 (forty) trees over aperiod of two years (2012-14).To test seasonal influence on the phenology of Barringtonia acutangula different phenophases were correlated with environmental variables and statistical spearman's rank correlation coefficient was employed. Aridity index was computed that delineate influence of rainfall and temperature together on any phenophases. Leaf initiation showed positively significant correlation with temperature (r(s) = 0.601, p = climate change, might have profound effect on phenophases of this tree species.

  10. Vegetative and reproductive phenology of a floodplain tree species Barringtonia acutangula from North East India.

    Science.gov (United States)

    Nath, Shikhasmita; Nath, Arun Jyoti; Das, Ashesh Kumar

    2016-03-01

    Vegetative and reproductive phenology of Barringtonia acutangula, a floodplain tree species was studied at Chatla floodplain, Assam North East India with the aim to investigate vegetative and reproductive phenology under stressful environment of seasonal submergence and to assess the impact of environmental variables (temperature and precipitation) on tree phenophases. Quantitative assessment was made at 15 day interval for all the phenophases (leaf initiation, leaf-fall, flowering and fruiting) by tagging 40 (forty) trees over aperiod of two years (2012-14).To test seasonal influence on the phenology of Barringtonia acutangula different phenophases were correlated with environmental variables and statistical spearman's rank correlation coefficient was employed. Aridity index was computed that delineate influence of rainfall and temperature together on any phenophases. Leaf initiation showed positively significant correlation with temperature (r(s) = 0.601, p = acutangula and any changes in these variables in future due to climate change, might have profound effect on phenophases of this tree species. PMID:27097440

  11. Groundlayer vegetation gradients across oak woodland canopy gaps

    Science.gov (United States)

    Pavlovic, N.B.; Grundel, R.; Sluis, W.

    2006-01-01

    Frequency of groundlayer plants was measured across oak woodland canopy gaps at three sites in northwest Indiana to examine how vegetation varied with gap size, direction along the gap edge, and microhabitat. Microhabitats were defined as under the canopy adjacent to the gap, along the gap edge, and within the gap. Gap-sites consisted of gaps plus adjacent tree canopy. Gaps were classified as small (16 ± 1 m2), medium (97 ± 8), and large (310 ± 32). Neither richness nor diversity differed among microhabitats, gap sizes, or edges. Similarity between microhabitats wthin a gap-site increased as the distance between plots decreased and as the difference in PAR decreased, the latter explaining twice the variation in percent dissimilarity compared to Mg concentration, A horizon depth, and litter cover. Diervilla lonicera, Frageria virginiana, Helianthus divaricatus, Polygonatum pubescens, Quercus velutina, Smilacena stellata, and Tradescantia ohiensis decreased, whileTephrosia virginiana and legumes increased in frequency, from canopy to gap, and C4 grasses peaked at the gap edge, independent of gap size. Additional species frequency varied across the microhabitat gradient within specific sites. Sorghastrum nutans was three times more frequent in gaps at large sites than elsewhere. The vegetation in medium-sized gap-sites was more variable than within small and large gap-sites, suggesting greater environmental heterogeneity at that scale. Within gap-sites, vegetation was more heterogeneous within edges and canopies than in gaps. Edges were more similar in composition to gaps than to canopy groundlayer within gap-sites. Few species varied significantly in frequency around the gap edge. The oak woodland groundlayer on sandy substrates can be characterized as a mosaic of forb dominated vegetation that varies across light gradients associated with canopy gaps, transitioning to islands of grassland vegetation when gaps exceed 160 m2.

  12. [Effects of temperature on CH4 emission from subtropical common tree species leaves].

    Science.gov (United States)

    Yang, Yan-Hua; Yi, Li-Ming; Xie, Jin-Sheng; Yang, Zhi-Jie; Jiang, Jun; Xu, Chao; Yang, Yu-Sheng

    2013-06-01

    Laboratory incubation test was conducted to study the effects of temperature on the CH4 emission from the leaves of subtropical common tree species Castanopsis carlesii, Schima superb, Cinnamomum chekiangense, Castsanopsis fabri, Cunninghamia lanceolata, and Citrus reticulata. Among the six tree species, only S. superb, C. reticulate, and C. fabri emitted CH4 at 10 degrees C. At above 20 degrees C, all the six species emitted CH4, and the average CH4 emission rate at above 30 degrees C (1.010 ng CH4 x g(-1) DM x h(-1)) was 2.96 times higher than that at 10-30 degrees C (0.255 ng CH4 x g(-1) DM x h(-1)). Moreover, increasing temperature had much more effects on the CH4 emission rate of C. reticulata and C. lanceolata than on that of the other four tree species. Incubation time affected the CH4 emission rate of all test tree species significantly, suggesting that the effects of temperature stress on the CH4 emission could be controlled by plant activity. Dry leaves could not emit CH4 no matter the temperature was very high or low. It was suggested that high temperature stress had important effects on the CH4 emission from subtropical tree leaves, and global warming could increase the CH4 emission from plants. PMID:24066538

  13. Discrimination of Deciduous Tree Species from Time Series of Unmanned Aerial System Imagery.

    Directory of Open Access Journals (Sweden)

    Jonathan Lisein

    Full Text Available Technology advances can revolutionize Precision Forestry by providing accurate and fine forest information at tree level. This paper addresses the question of how and particularly when Unmanned Aerial System (UAS should be used in order to efficiently discriminate deciduous tree species. The goal of this research is to determine when is the best time window to achieve an optimal species discrimination. A time series of high resolution UAS imagery was collected to cover the growing season from leaf flush to leaf fall. Full benefit was taken of the temporal resolution of UAS acquisition, one of the most promising features of small drones. The disparity in forest tree phenology is at the maximum during early spring and late autumn. But the phenology state that optimized the classification result is the one that minimizes the spectral variation within tree species groups and, at the same time, maximizes the phenologic differences between species. Sunlit tree crowns (5 deciduous species groups were classified using a Random Forest approach for monotemporal, two-date and three-date combinations. The end of leaf flushing was the most efficient single-date time window. Multitemporal datasets definitely improve the overall classification accuracy. But single-date high resolution orthophotomosaics, acquired on optimal time-windows, result in a very good classification accuracy (overall out of bag error of 16%.

  14. Inferring duplications, losses, transfers and incomplete lineage sorting with nonbinary species trees

    Science.gov (United States)

    Stolzer, Maureen; Lai, Han; Xu, Minli; Sathaye, Deepa; Vernot, Benjamin; Durand, Dannie

    2012-01-01

    Motivation: Gene duplication (D), transfer (T), loss (L) and incomplete lineage sorting (I) are crucial to the evolution of gene families and the emergence of novel functions. The history of these events can be inferred via comparison of gene and species trees, a process called reconciliation, yet current reconciliation algorithms model only a subset of these evolutionary processes. Results: We present an algorithm to reconcile a binary gene tree with a nonbinary species tree under a DTLI parsimony criterion. This is the first reconciliation algorithm to capture all four evolutionary processes driving tree incongruence and the first to reconcile non-binary species trees with a transfer model. Our algorithm infers all optimal solutions and reports complete, temporally feasible event histories, giving the gene and species lineages in which each event occurred. It is fixed-parameter tractable, with polytime complexity when the maximum species outdegree is fixed. Application of our algorithms to prokaryotic and eukaryotic data show that use of an incomplete event model has substantial impact on the events inferred and resulting biological conclusions. Availability: Our algorithms have been implemented in Notung, a freely available phylogenetic reconciliation software package, available at http://www.cs.cmu.edu/~durand/Notung. Contact: mstolzer@andrew.cmu.edu PMID:22962460

  15. Fruit availability, frugivore satiation and seed removal in 2 primate-dispersed tree species.

    Science.gov (United States)

    Ratiarison, Sandra; Forget, Pierre-Michel

    2011-09-01

    During a mast-fruiting event we investigated spatial variability in fruit availability, consumption, and seed removal at two sympatric tree species, Manilkara bidentata and M. huberi (Sapotaceae) at Nouragues Natural Reserve, French Guiana. We addressed the question of how Manilkara density and fruits at the community level might be major causes of variability in feeding assemblages between tree species. We thus explored how the frugivore assemblages differed between forest patches with contrasting relative Manilkara density and fruiting context. During the daytime, Alouatta seniculus was more often observed in M. huberi crowns at Petit Plateau (PP) with the greatest density of Manilkara spp. and the lowest fruit diversity and availability, whereas Cebus apella and Saguinus midas were more often observed in M. bidentata crowns at both Grand Plateau (GP), with a lowest density of M. bidentata and overall greater fruit supply, and PP. Overall, nearly 53% and 15% of the M. bidentata seed crop at GP and PP, respectively, and about 47% of the M. huberi seed crop were removed, otherwise either spit out or defecated beneath trees, or dropped in fruits. Small-bodied primates concentrated fallen seeds beneath parent trees while large-bodied primate species removed and dispersed more seeds away from parents. However, among the latter, satiated A. seniculus wasted seeds under conspecific trees at PP. Variations in feeding assemblages, seed removal rates and fates possibly reflected interactions with extra-generic fruit species at the community level, according to feeding choice, habitat preferences and ranging patterns of primate species. PMID:21910838

  16. O factor de coberto vegetal, para árvores e Arbustos, em modelos de erosão hídrica The vegetation cover factor, for tree and bush canopies, in models of water erosion

    Directory of Open Access Journals (Sweden)

    Carla Rolo Antunes

    2011-07-01

    Full Text Available O objectivo primordial do presente trabalho consiste na análise do comportamento de cobertos arbóreos e arbustivos, em termos do processo de intercepção da precipitação, designadamente, retenção e gotejo, e no estabelecimento de uma componente a incluir em modelos de erosão, que permita quantificar o factor de coberto vegetal em caso de ocupação do solo por estes cobertos, associados a culturas arvenses, em subcoberto, particularmente, na Equação Universal da Perda de Solo Revista (RUSLE. O trabalho experimental utilizou um simulador de chuva, tendo-se obtido valores do diâmetro das gotas (gotejo das folhas de espécies características dos sistemas de uso do solo mais comuns no Sul de Portugal, nomeadamente sobreiro (Quercus suber L., azinheira (Quercus ilex L. ssp. rotundifolia Lam e carrasco (Quercus coccifera L., e quantificado valores de retenção nas folhas. A partir dos resultados obtidos estimou-se a energia cinética para diferentes alturas de queda e, consequentemente, valores correctivos a aplicar aos valores de C tradicionalmente considerados, relativos às culturas agrícolas.The main objective of this work consists on the analyzes of tree and bush canopies behavior, in terms of the rainfall interception process, namely, leave retention, and dripping, and the establishment of a erosion model component to include in to quantify the cover factor (C of the Revised Universal Soil Loss Equation (RUSLE for mixed land covered systems with arable crops, in association with trees and bushes. In the experimental work a rainfall simulator was used and the characteristic values for the diameter of the dripping drops and retention of the leaves from characteristic species of the more common mixed land-use systems in Southern of Portugal, particularly with Cork oak (Quercus suber L., Holm or evergreen oak (Quercus ilex L. ssp. rotundifolia Lam and Kermes or wild oak (Quercus coccifera L., were obtained. From the obtained results

  17. High-throughput transcriptome sequencing and preliminary functional analysis in four Neotropical tree species

    OpenAIRE

    Brousseau, Louise; Tinaut, Alexandra; Duret, Caroline; Lang, Tiange; Garnier-Gere, Pauline; Scotti, Ivan

    2014-01-01

    Background The Amazonian rainforest is predicted to suffer from ongoing environmental changes. Despite the need to evaluate the impact of such changes on tree genetic diversity, we almost entirely lack genomic resources. Results In this study, we analysed the transcriptome of four tropical tree species (Carapa guianensis, Eperua falcata, Symphonia globulifera and Virola michelii) with contrasting ecological features, belonging to four widespread botanical families (respectively Meliaceae, Fab...

  18. Growth and Physiology of Several Urban Tree Species in Soils Disturbed by Construction Fill or Compaction

    OpenAIRE

    Day, Susan Downing

    1999-01-01

    Experiments were conducted to determine the effects of applying fill soil around existing trees and mechanisms for species tolerance to soil compaction, both common site disturbances in urban forestry. Groups of 22-year-old white oak (Quercus alba) and 13-year-old sweetgum (Liquidambar styraciflua) were subjected to one of three treatments: a control, fill (20 cm of subsoil spread over the root zones), and compacted fill (same as fill soil, but compacted). Additionally, individual trees had t...

  19. Physiological characteristics of tropical rain forest tree species: A basis for the development of silvicultural technology

    OpenAIRE

    SASAKI, Satohiko

    2008-01-01

    The physiological characteristics of the dominant tree species in the tropical rain forest mainly belonging to dipterocarps as well as the environmental conditions especially for the light in the forest were studied to establish the silvicultural system for the forest regeneration in the tropical South Asia. The flowering patterns of the dipterocarp trees are usually irregular and unpredictable, which make difficult to collect sufficient seeds for raising the seedlings. The field survey revea...

  20. Fast demographic traits promote high diversification rates of Amazonian trees

    OpenAIRE

    Baker, Timothy R.; Pennington, R. Toby; Magallon, Susana; Gloor, Emanuel; Laurance, William F.; Alexiades, Miguel; Alvarez, Esteban; Araujo, Alejandro; Arets, Eric J. M. M.; Aymard, Gerardo; de Oliveira, Atila Alves; Amaral, Iêda; Arroyo, Luzmila; Bonal, Damien; Roel J.W. Brienen

    2014-01-01

    The Amazon rain forest sustains the world's highest tree diversity, but it remains unclear why some clades of trees are hyperdiverse, whereas others are not. Using dated phylogenies, estimates of current species richness and trait and demographic data from a large network of forest plots, we show that fast demographic traits - short turnover times - are associated with high diversification rates across 51 clades of canopy trees. This relationship is robust to assuming that diversification rat...

  1. Canopy and leaf composition drive patterns of nutrient release from pruning residues in a coffee agroforest.

    Science.gov (United States)

    Tully, Katherine L; Lawrence, Deborah

    2012-06-01

    In a coffee agroforest, the crop is cultivated under the shade of fruit-bearing and nitrogen (N)-fixing trees. These trees are periodically pruned to promote flowering and fruiting as well as to make nutrients stored in tree biomass available to plants. We investigated the effect of canopy composition and substrate quality on decomposition rates and patterns of nutrient release from pruning residues in a coffee agroforest located in Costa Rica's Central Valley. Initial phosphorus (P) release was enhanced under a canopy composed solely of N-fixing, Erythrina poeppigiana compared to a mixed canopy of Erythrina and Musa acuminata (banana). Both initial and final N release were similar under the two canopy types. However, after five months of decomposition, a higher proportion of initial N had been released under the single canopy. Although patterns of decomposition and nutrient release were not predicted by initial substrate quality, mass loss in leaf mixtures rates were well predicted by mean mass loss of their component species. This study identifies specific pruning regimes that may regulate N and P release during crucial growth periods, and it suggests that strategic pruning can enhance nutrient availability. For example, during the onset of rapid fruit growth, a two-species mixture may release more P than a three-species mixture. However, by the time of the harvest, the two- and three-species mixtures have released roughly the same amount of N and P. These nutrients do not always follow the same pattern, as N release can be maximized in single-species substrates, while P release is often facilitated in species mixtures. Our study indicates the importance of management practices in mediating patterns of nutrient release. Future research should investigate how canopy composition and farm management can also mediate on-farm nutrient losses.

  2. Canopy and leaf composition drive patterns of nutrient release from pruning residues in a coffee agroforest.

    Science.gov (United States)

    Tully, Katherine L; Lawrence, Deborah

    2012-06-01

    In a coffee agroforest, the crop is cultivated under the shade of fruit-bearing and nitrogen (N)-fixing trees. These trees are periodically pruned to promote flowering and fruiting as well as to make nutrients stored in tree biomass available to plants. We investigated the effect of canopy composition and substrate quality on decomposition rates and patterns of nutrient release from pruning residues in a coffee agroforest located in Costa Rica's Central Valley. Initial phosphorus (P) release was enhanced under a canopy composed solely of N-fixing, Erythrina poeppigiana compared to a mixed canopy of Erythrina and Musa acuminata (banana). Both initial and final N release were similar under the two canopy types. However, after five months of decomposition, a higher proportion of initial N had been released under the single canopy. Although patterns of decomposition and nutrient release were not predicted by initial substrate quality, mass loss in leaf mixtures rates were well predicted by mean mass loss of their component species. This study identifies specific pruning regimes that may regulate N and P release during crucial growth periods, and it suggests that strategic pruning can enhance nutrient availability. For example, during the onset of rapid fruit growth, a two-species mixture may release more P than a three-species mixture. However, by the time of the harvest, the two- and three-species mixtures have released roughly the same amount of N and P. These nutrients do not always follow the same pattern, as N release can be maximized in single-species substrates, while P release is often facilitated in species mixtures. Our study indicates the importance of management practices in mediating patterns of nutrient release. Future research should investigate how canopy composition and farm management can also mediate on-farm nutrient losses. PMID:22827139

  3. Uptake and Translocation of Manganese by Native Tree Species in a Constructed Wetland Treating Landfill Leachates

    Directory of Open Access Journals (Sweden)

    A. Snow

    2007-01-01

    Full Text Available A surface flow constructed wetland was used to treat stormwater runoff from surrounding watersheds which are comprised primarily of commercial properties and two former landfills. The uptake of manganese by red maple, white birch and red spruce trees growing under flooded soil conditions in the constructed wetland was compared to that of the same trees growing under well drained soil conditions in a nearby reference site. The seasonal variability of manganese and its distribution in different compartments of these trees (leaves, twigs, branches, trunk wood, trunk bark and roots were studied. The average manganese concentrations in the aboveground compartments of red maple, white birch and red spruce trees were within the range of manganese concentrations reported in the literature for these trees. The concentrations of manganese in the aboveground compartments of red maple, white birch and red spruce trees in the reference site were significantly greater than those in the constructed wetland (with the exception of manganese concentrations in the trunk wood of red maple trees because of the acidic soil conditions of the reference site. The percent distribution of manganese in the aboveground compartments of trees did not vary during the growing season. Higher concentrations of manganese were present in the trunk bark and either the leaves or twigs of species on both the constructed wetland and the reference site regardless of the sampling date.

  4. Estimating tree bole volume using artificial neural network models for four species in Turkey.

    Science.gov (United States)

    Ozçelik, Ramazan; Diamantopoulou, Maria J; Brooks, John R; Wiant, Harry V

    2010-01-01

    Tree bole volumes of 89 Scots pine (Pinus sylvestris L.), 96 Brutian pine (Pinus brutia Ten.), 107 Cilicica fir (Abies cilicica Carr.) and 67 Cedar of Lebanon (Cedrus libani A. Rich.) trees were estimated using Artificial Neural Network (ANN) models. Neural networks offer a number of advantages including the ability to implicitly detect complex nonlinear relationships between input and output variables, which is very helpful in tree volume modeling. Two different neural network architectures were used and produced the Back propagation (BPANN) and the Cascade Correlation (CCANN) Artificial Neural Network models. In addition, tree bole volume estimates were compared to other established tree bole volume estimation techniques including the centroid method, taper equations, and existing standard volume tables. An overview of the features of ANNs and traditional methods is presented and the advantages and limitations of each one of them are discussed. For validation purposes, actual volumes were determined by aggregating the volumes of measured short sections (average 1 meter) of the tree bole using Smalian's formula. The results reported in this research suggest that the selected cascade correlation artificial neural network (CCANN) models are reliable for estimating the tree bole volume of the four examined tree species since they gave unbiased results and were superior to almost all methods in terms of error (%) expressed as the mean of the percentage errors. PMID:19880241

  5. Identification and Mapping of Tree Species in Urban Areas Using WORLDVIEW-2 Imagery

    Science.gov (United States)

    Mustafa, Y. T.; Habeeb, H. N.; Stein, A.; Sulaiman, F. Y.

    2015-10-01

    Monitoring and mapping of urban trees are essential to provide urban forestry authorities with timely and consistent information. Modern techniques increasingly facilitate these tasks, but require the development of semi-automatic tree detection and classification methods. In this article, we propose an approach to delineate and map the crown of 15 tree species in the city of Duhok, Kurdistan Region of Iraq using WorldView-2 (WV-2) imagery. A tree crown object is identified first and is subsequently delineated as an image object (IO) using vegetation indices and texture measurements. Next, three classification methods: Maximum Likelihood, Neural Network, and Support Vector Machine were used to classify IOs using selected IO features. The best results are obtained with Support Vector Machine classification that gives the best map of urban tree species in Duhok. The overall accuracy was between 60.93% to 88.92% and κ-coefficient was between 0.57 to 0.75. We conclude that fifteen tree species were identified and mapped at a satisfactory accuracy in urban areas of this study.

  6. Trees

    Science.gov (United States)

    Al-Khaja, Nawal

    2007-01-01

    This is a thematic lesson plan for young learners about palm trees and the importance of taking care of them. The two part lesson teaches listening, reading and speaking skills. The lesson includes parts of a tree; the modal auxiliary, can; dialogues and a role play activity.

  7. Novel Phaeoacremonium species associated with necrotic wood of Prunus trees.

    Science.gov (United States)

    Damm, U; Mostert, L; Crous, P W; Fourie, P H

    2008-06-01

    The genus Phaeoacremonium is associated with opportunistic human infections, as well as stunted growth and die-back of various woody hosts, especially grapevines. In this study, Phaeoacremonium species were isolated from necrotic woody tissue of Prunus spp. (plum, peach, nectarine and apricot) from different stone fruit growing areas in South Africa. Morphological and cultural characteristics as well as DNA sequence data (5.8S rDNA, ITS1, ITS2, beta-tubulin, actin and 18S rDNA) were used to identify known, and describe novel species. From the total number of wood samples collected (257), 42 Phaeoacremonium isolates were obtained, from which 14 species were identified. Phaeoacremonium scolyti was most frequently isolated, and present on all Prunus species sampled, followed by Togninia minima (anamorph: Pm. aleophilum) and Pm. australiense. Almost all taxa isolated represent new records on Prunus. Furthermore, Pm. australiense,Pm. iranianum, T. fraxinopennsylvanica and Pm. griseorubrum represent new records for South Africa, while Pm. griseorubrum, hitherto only known from humans, is newly reported from a plant host. Five species are newly described, two of which produce a Togninia sexual state. Togninia africana, T. griseo-olivacea and Pm. pallidum are newly described from Prunus armeniaca, while Pm. prunicolum and Pm. fuscum are described from Prunus salicina.

  8. Tree Species Detection Accuracies Using Discrete Point Lidar and Airborne Waveform Lidar

    OpenAIRE

    Turnblom, Eric C.; L. Monika Moskal; Vaughn, Nicholas R.

    2012-01-01

    Species information is a key component of any forest inventory. However, when performing forest inventory from aerial scanning Lidar data, species classification can be very difficult. We investigated changes in classification accuracy while identifying five individual tree species (Douglas-fir, western redcedar, bigleaf maple, red alder, and black cottonwood) in the Pacific Northwest United States using two data sets: discrete point Lidar data alone and discrete point data in combination wit...

  9. The effect of canopy closure on chimpanzee nest abundance in Lagoas de Cufada National Park, Guinea-Bissau.

    Science.gov (United States)

    Sousa, Joana; Casanova, Catarina; Barata, André V; Sousa, Cláudia

    2014-04-01

    The present study aimed to gather baseline information about chimpanzee nesting and density in Lagoas de Cufada Natural Park (LCNP), in Guinea-Bissau. Old and narrow trails were followed to estimate chimpanzee density through marked-nest counts and to test the effect of canopy closure (woodland savannah, forest with a sparse canopy, and forest with a dense canopy) on nest distribution. Chimpanzee abundance was estimated at 0.79 nest builders/km(2), the lowest among the areas of Guinea-Bissau with currently studied chimpanzee populations. Our data suggest that sub-humid forest with a dense canopy accounts for significantly higher chimpanzee nest abundance (1.50 nests/km of trail) than sub-humid forest with a sparse canopy (0.49 nests/km of trail) or woodland savannah (0.30 nests/km of trail). Dense-canopy forests play an important role in chimpanzee nesting in the patchy and highly humanized landscape of LCNP. The tree species most frequently used for nesting are Dialium guineense (46 %) and Elaeis guineensis (28 %). E. guineensis contain nests built higher in the canopy, while D. guineense contain nests built at lower heights. Nests observed during baseline sampling and replications suggest seasonal variations in the tree species used for nest building. PMID:24408762

  10. Warming effects on photosynthesis of subtropical tree species: a translocation experiment along an altitudinal gradient.

    Science.gov (United States)

    Li, Yiyong; Liu, Juxiu; Zhou, Guoyi; Huang, Wenjuan; Duan, Honglang

    2016-01-01

    Ongoing climate warming induced by human activities may have great impacts on trees, yet it remains unresolved how subtropical tree species respond to rising temperature in the field. Here, we used downward translocation to investigate the effects of climate warming on leaf photosynthesis of six common tree species in subtropical China. During the experimental period between 2012 and 2014, the mean average photosynthetic rates (Asat) under saturating light for Schima superba, Machilus breviflora, Pinus massoniana and Ardisia lindleyana in the warm site were7%, 19%, 20% and 29% higher than those in the control site. In contrast, seasonal Asat for Castanopsis hystrix in the warm site were lower compared to the control site. Changes in Asat in response to translocation were mainly associated with those in leaf stomatal conductance (gs) and photosynthetic capacity (RuBP carboxylation, RuBP regeneration capacity). Our results imply that climate warming could have potential impacts on species composition and community structure in subtropical forests. PMID:27102064

  11. THE IMPORTANCE OF USING FRUIT TREE SPECIES WITH ORNAMENTAL ROLE IN RUSTIC GARDENS LANDSCAPING

    Directory of Open Access Journals (Sweden)

    Roxana Negrea

    2012-04-01

    Full Text Available Ornamental fruit trees are suitable for rustic gardens, although "rustic" is translated to us especially by "poverty" or "obsolete", in much broader terms refers to "something else " meaning return to nature, respect, tradition and even a certain social status. It is therefore essential that in the woody vegetation campestre gardens to find rustic tree species, which by their habitus and color bring moredynamism and candor to any type of garden, especially rustic garden type. These species can be introduced into the composition either as individual parts or grups, decorating the trees in the same visualcharacter (class, habitus, foliage, flowers, also providing the desired fruit. The great advantage of these species is that in addition to their great capacity to make the area in which they are positioned beautiful, by the beauty of the flowers, leaves or even the different colors every season, offers real taste delights through the fruit they produce.

  12. Influences of forest structure, climate and species composition on tree mortality across the eastern US.

    Science.gov (United States)

    Lines, Emily R; Coomes, David A; Purves, Drew W

    2010-10-13

    Few studies have quantified regional variation in tree mortality, or explored whether species compositional changes or within-species variation are responsible for regional patterns, despite the fact that mortality has direct effects on the dynamics of woody biomass, species composition, stand structure, wood production and forest response to climate change. Using bayesian analysis of over 430,000 tree records from a large eastern US forest database we characterised tree mortality as a function of climate, soils, species and size (stem diameter). We found (1) mortality is U-shaped vs. stem diameter for all 21 species examined; (2) mortality is hump-shaped vs. plot basal area for most species; (3) geographical variation in mortality is substantial, and correlated with several environmental factors; and (4) individual species vary substantially from the combined average in the nature and magnitude of their mortality responses to environmental variation. Regional variation in mortality is therefore the product of variation in species composition combined with highly varied mortality-environment correlations within species. The results imply that variation in mortality is a crucial part of variation in the forest carbon cycle, such that including this variation in models of the global carbon cycle could significantly narrow uncertainty in climate change predictions.

  13. Influences of forest structure, climate and species composition on tree mortality across the eastern US.

    Directory of Open Access Journals (Sweden)

    Emily R Lines

    Full Text Available Few studies have quantified regional variation in tree mortality, or explored whether species compositional changes or within-species variation are responsible for regional patterns, despite the fact that mortality has direct effects on the dynamics of woody biomass, species composition, stand structure, wood production and forest response to climate change. Using bayesian analysis of over 430,000 tree records from a large eastern US forest database we characterised tree mortality as a function of climate, soils, species and size (stem diameter. We found (1 mortality is U-shaped vs. stem diameter for all 21 species examined; (2 mortality is hump-shaped vs. plot basal area for most species; (3 geographical variation in mortality is substantial, and correlated with several environmental factors; and (4 individual species vary substantially from the combined average in the nature and magnitude of their mortality responses to environmental variation. Regional variation in mortality is therefore the product of variation in species composition combined with highly varied mortality-environment correlations within species. The results imply that variation in mortality is a crucial part of variation in the forest carbon cycle, such that including this variation in models of the global carbon cycle could significantly narrow uncertainty in climate change predictions.

  14. Separation of the bioclimatic spaces of Himalayan tree rhododendron species predicted by ensemble suitability models

    Directory of Open Access Journals (Sweden)

    Sailesh Ranjitkar

    2014-08-01

    Full Text Available The tree rhododendrons include the most widely distributed Himalayan Rhododendron species belonging to the subsection Arborea. Distributions of two members of this sub-species were modelled using bioclimatic data for current conditions (1950–2000. A subset of the least correlated bioclimatic variables was used for ecological niche modelling (ENM. We used an ENM ensemble method in the BiodiversityR R-package to map the suitable climatic space for tree rhododendrons based on 217 point location records. Ensemble bioclimatic models for tree rhododendrons had high predictive power with bioclimatic variables, which also separated the climatic spaces for the two species. Tree rhododendrons were found occurring in a wide range of climate and the distributional limits were associated with isothermality, temperature ranges, temperature of the wettest quarter, and precipitation of the warmest quarter of the year. The most suitable climatic space for tree rhododendrons was predicted to be in western Yunnan, China, with suitability declining towards the west and east. Its occurrence in a wide range of climatic settings with highly dissected habitats speaks to the adaptive capacity of the species, which might open up future options for their conservation planning in regions where they are listed as threatened.

  15. Toward more accurate ancestral protein genotype-phenotype reconstructions with the use of species tree-aware gene trees.

    Science.gov (United States)

    Groussin, Mathieu; Hobbs, Joanne K; Szöllősi, Gergely J; Gribaldo, Simonetta; Arcus, Vickery L; Gouy, Manolo

    2015-01-01

    The resurrection of ancestral proteins provides direct insight into how natural selection has shaped proteins found in nature. By tracing substitutions along a gene phylogeny, ancestral proteins can be reconstructed in silico and subsequently synthesized in vitro. This elegant strategy reveals the complex mechanisms responsible for the evolution of protein functions and structures. However, to date, all protein resurrection studies have used simplistic approaches for ancestral sequence reconstruction (ASR), including the assumption that a single sequence alignment alone is sufficient to accurately reconstruct the history of the gene family. The impact of such shortcuts on conclusions about ancestral functions has not been investigated. Here, we show with simulations that utilizing information on species history using a model that accounts for the duplication, horizontal transfer, and loss (DTL) of genes statistically increases ASR accuracy. This underscores the importance of the tree topology in the inference of putative ancestors. We validate our in silico predictions using in vitro resurrection of the LeuB enzyme for the ancestor of the Firmicutes, a major and ancient bacterial phylum. With this particular protein, our experimental results demonstrate that information on the species phylogeny results in a biochemically more realistic and kinetically more stable ancestral protein. Additional resurrection experiments with different proteins are necessary to statistically quantify the impact of using species tree-aware gene trees on ancestral protein phenotypes. Nonetheless, our results suggest the need for incorporating both sequence and DTL information in future studies of protein resurrections to accurately define the genotype-phenotype space in which proteins diversify.

  16. Diversity and utilization of tree species in Meitei homegardens of Barak Valley, Assam.

    Science.gov (United States)

    Devi, N Linthoingambi; Das, Ashesh Kumar

    2013-03-01

    An inventory of tree diversity in traditional homegardens of Meitei community was conducted in a Bontarapur village in Cachar district of Barak Valley, Assam. Meitei homegarden locally called Ingkhol exhibits a wide diversity in size, shape, location and composition. Seventy one tree species were enumerated from 50 homegardens belonging to 60 genus and 35 families. Among the families encountered, Rutaceae was the dominant family (4 genus and 7 species) followed by Meliaceae (5 genus and 5 species), Arecaceae (4 genus and 4 species) and Moraceae (3 genus and 5 species). Total 7946 tree individuals were recorded, with the density of 831 No ha(-1) of and total basal area of 9.54 m2 ha(-1). Areco catechu was the dominant species with the maximum number of individuals. Other dominant trees include Mangifera indica, Artocarpus heterophyllus, Citrus grandis, Parkia timoriana, Syzygium cumini and Psidium guajava. Being a cash crop, the intensification of betel nut has been preferred in many homegardens. Homegardens form an important component of land use of Meitei community which fulfills the socio-cultural and economic needs of the family and helps in conserving plant diversity through utilization.

  17. The role of selected tree species in industrial sewage sludge/flotation tailing management.

    Science.gov (United States)

    Mleczek, Mirosław; Rutkowski, Paweł; Niedzielski, Przemysław; Goliński, Piotr; Gąsecka, Monika; Kozubik, Tomisław; Dąbrowski, Jędrzej; Budzyńska, Sylwia; Pakuła, Jarosław

    2016-11-01

    The aim of the study was to estimate the ability of ten tree and bush species to tolerate and accumulate Cd, Cu, Pb, Zn, and As species [As(III), As(V), and total organic arsenic] in industrial sewage sludge extremely contaminated with arsenic (almost 27.5 g kg(-1)) in a pot experiment. The premise being that it will then be possible to select the most promising tree/bush species, able to grow in the vicinity of dams where sewage sludge/flotation tailings are used as landfill. Six of the ten tested tree species were able to grow on the sludge. The highest content of total As was observed in Betula pendula roots (30.0 ± 1.3 mg kg(-1) DW), where the dominant As species was the toxic As(V). The highest biomass of Quercus Q1 robur (77.3 § 2.6 g) and Acer platanoides (76.0 § 4.9 g) was observed. A proper planting of selected tree species that are able to thrive on sewage sludge/flotation tailings could be an interesting and promising way to protect dams. By utilizing differences in their root systems and water needs, we will be able to reduce the risk of fatal environmental disasters. PMID:27348264

  18. Toward a better understanding of the subtropical Atlantic Forest in the state of Santa Catarina, Brazil: tree sampling accuracy, species richness and frequency of rare species

    OpenAIRE

    Vanessa Leite Rezende; Eisenlohr, Pedro V.; André Luís de Gasper; Alexander Christian Vibrans; Ary Teixeira de Oliveira-Filho

    2014-01-01

    Accurate knowledge of floristic composition is crucial when planning and designing research projects and public policies. In this study, our goal was to assess tree sampling accuracy and to identify sites with higher concentrations of rare tree species, as well as those with the highest tree species richness, in the state of Santa Catarina, Brazil. We determined sampling accuracy using the first-order jackknife and Chao 2 estimators, calculated the number of rare species (singletons and doubl...

  19. Novel Phaeoacremonium species associated with necrotic wood of Prunus trees

    NARCIS (Netherlands)

    Damm, U.; Mostert, L.; Crous, P.W.; Fourie, P.H.

    2008-01-01

    The genus Phaeoacremonium is associated with opportunistic human infections, as well as stunted growth and die-back of various woody hosts, especially grapevines. In this study, Phaeoacremonium species were isolated from necrotic woody tissue of Prunus spp. (plum, peach, nectarine and apricot) from

  20. 林木种间的化感作用%Effects of Allelopathy Among Tree Species

    Institute of Scientific and Technical Information of China (English)

    林文欢; 詹潮安; 陈红跃

    2011-01-01

    Effects of allelopathy among plants are a common phenomenon in natural world.Allelopathic effects play important roles on crop cultivation,weed control,pest control and plantation building.Collocation of tree species is a key factor in mixed plantation building.Effects of allelopathy among tree species play a crucial role in selection of tree species.The paper reviewed the research advances on allelopathic effects among the common tree species in mixed plantation in terms of collection and extraction of allelochemicals,authentication of allelochemicals and expressions of allelopathic effects.The research on the allelopathic effects among the tree species was aimed at providing scientific basis for tree species composition of plantation and giving service support to non-commercial forest.%植物化感作用是自然界普遍存在的一种现象,在农作物耕作、杂草控制、病虫害防治以及林木营造等方面发挥着重要作用。树种搭配是成功营造人工混交林的关键,林木种间的化感作用在混交树种的选择上起着重要作用。文中从化感物质的收集与提取、化感物质的鉴定以及化感作用的表达等方面,对人工混交林常见树种间化感作用的研究情况和成果进行综述,以期为混交林选择树种组合提供科学依据,为生态公益林建设服务。

  1. Effects of pioneer tree species hyperabundance on forest fragments in northeastern Brazil.

    Science.gov (United States)

    Tabarelli, Marcelo; Aguiar, Antonio V; Girão, Luciana C; Peres, Carlos A; Lopes, Ariadna V

    2010-12-01

    Despite many studies on fragmentation of tropical forests, the extent to which plant and animal communities are altered in small, isolated forest fragments remains obscure if not controversial. We examined the hypothesis that fragmentation alters the relative abundance of tree species with different vegetative and reproductive traits. In a fragmented landscape (670 km(2) ) of the Atlantic Forest of northeastern Brazil, we categorized 4056 trees of 182 species by leafing pattern, reproductive phenology, and morphology of seeds and fruit. We calculated relative abundance of traits in 50 1-ha plots in three types of forest configurations: forest edges, small forest fragments (3.4-83.6 ha), and interior of the largest forest fragment (3500 ha, old growth). Although evergreen species were the most abundant across all configurations, forest edges and small fragments had more deciduous and semideciduous species than interior forest. Edges lacked supra-annual flowering and fruiting species and had more species and stems with drupes and small seeds than small forest fragments and forest interior areas. In an ordination of species similarity and life-history traits, the three types of configurations formed clearly segregated clusters. Furthermore, the differences in the taxonomic and functional (i.e., trait-based) composition of tree assemblages we documented were driven primarily by the higher abundance of pioneer species in the forest edge and small forest fragments. Our work provides strong evidence that long-term transitions in phenology and seed and fruit morphology of tree functional groups are occurring in fragmented tropical forests. Our results also suggest that edge-induced shifts in tree assemblages of tropical forests can be larger than previously documented.

  2. Complementary models of tree species-soil relationships in old-growth temperate forests

    Science.gov (United States)

    Cross, Alison; Perakis, Steven S.

    2011-01-01

    Ecosystem level studies identify plant soil feed backs as important controls on soil nutrient availability,particularly for nitrogen and phosphorus. Although site and species specific studies of tree species soil relationships are relatively common,comparatively fewer studies consider multiple coexisting speciesin old-growth forests across a range of sites that vary underlying soil fertility. We characterized patterns in forest floor and mineral soil nutrients associated with four common tree species across eight undisturbed old-growth forests in Oregon, USA, and used two complementary conceptual models to assess tree species soil relationships. Plant soil feedbacks that could reinforce sitelevel differences in nutrient availability were assessed using the context dependent relationships model, where by relative species based differences in each soil nutrient divergedorconvergedas nutrient status changed across sites. Tree species soil relationships that did not reflect strong feedbacks were evaluated using a site independent relationships model, where by forest floor and surface mineral soil nutrient tools differed consistently by tree species across sites,without variation in deeper mineral soils. We found that theorganically cycled elements carbon, nitrogen, and phosphorus exhibited context-dependent differences among species in both forest floor and mineral soil, and most of ten followed adivergence model,where by species differences were greatest at high-nutrient sites. These patterns are consistent with the oryemphasizing biotic control of these elements through plant soil feedback mechanisms. Site independent species differences were strongest for pool so if the weather able cations calcium, magnesium, potassium,as well as phosphorus, in mineral soils. Site independent species differences in forest floor nutrients we reattributable too nespecies that displayed significant greater forest floor mass accumulation. Our finding confirmed that site-independent and

  3. The Exotic Legume Tree Species Acacia holosericea Alters Microbial Soil Functionalities and the Structure of the Arbuscular Mycorrhizal Community▿

    OpenAIRE

    Remigi, P.; Faye, A; A. Kane; Deruaz, M.; Thioulouse, J.; Cissoko, M.; Prin, Y.; Galiana, A; Dreyfus, B.; Duponnois, R.

    2008-01-01

    The response of microbial functional diversity as well as its resistance to stress or disturbances caused by the introduction of an exotic tree species, Acacia holosericea, ectomycorrhized or not with Pisolithus albus, was examined. The results show that this ectomycorrhizal fungus promotes drastically the growth of this fast-growing tree species in field conditions after 7 years of plantation. Compared to the crop soil surrounding the A. holosericea plantation, this exotic tree species, asso...

  4. The effect of drought on forest tree species' nourishment: the chosen path of phosphorus cycling

    OpenAIRE

    Marfo, Theodore Danso

    2015-01-01

    This research sought to evaluate the effect of drought on forest tree species with emphasis on bio-available phosphorus obtained via phosphorus cycling. Soil samples were collected at root zone depth from areas of varied altitudes and tree species thus H-horizon soils from the mountain Spruce forest at Bily Kriz, A-horizon soils from both the young Spruce monoculture at Rajec and Beech forest at Stitna. Acid phosphatase activity of the various soil samples was measured in optimal conditions o...

  5. Association of dominated tree species in lowland tropical forest of Tangkoko Nature Reserve, Bitung, North Sulawesi

    Directory of Open Access Journals (Sweden)

    AGUNG KURNIAWAN

    2008-07-01

    Full Text Available The study aimed to gain information about tree species domination and association was conducted in lowland tropical forest of Tangkoko Nature Reserve. The tree with ≥10 cm dbh censused with quarter method. The result showed that Palaquium sp. having the highest domination species with Index Importance Value 21.05, as well as Cananga odorata Hook.f. & Thoms. and Dracontomelon dao (Blanco Merril & Rolfe. There was one couple species that had positive association among seven main species composition in area study, that was C. odorata with kayu kapur. Generally, the other couples species had negative association, so there was no tolerance to exist in the same area and no mutualism interrelationship especially in habitat grouping.

  6. Estimation of Chlorophyll Content in Apple Tree Canopy Based on Hyperspectral Parameters%利用高光谱植被指数估测苹果树冠层叶绿素含量

    Institute of Scientific and Technical Information of China (English)

    潘蓓; 赵庚星; 朱西存; 刘海腾; 梁爽; 田大德

    2013-01-01

    叶绿素含量是反映植物生长状况的重要参数.利用ASD FieldSpec 3光谱仪,测定春梢停止生长期苹果冠层高光谱反射率,对原始光谱进行微分变换,与苹果叶绿素含量进行相关分析确定敏感波段,通过分析敏感区域400~1 350nm范围内所有两波段组合的植被指数,选择最佳植被指数并建立苹果冠层叶绿素含量估测模型.结果表明:(1)苹果冠层叶绿素含量的敏感波段区域为400~1 350nm.(2)利用筛选得到的植被指数CCI (D794/D763)构建的估测模型能较好的估测苹果冠层叶绿素含量.(3)以CCI (D794/D763)指数为自变量的估测模型CCC=6.409+1.89R3+1.587R2-7.779R预测效果最佳.因此,利用高光谱技术能够较快速、精确的对苹果冠层叶绿素含量进行定量化反演,为苹果长势的遥感监测提供理论依据.%The hyperspectral reflectance of apple tree canopy during spring shoots stopping growth period was measured using ASD FieldSpec3 field spectrometer.Original spectral data were processed in deviation forms,and significant spectrum parameters correlated with chlorophyll content were found out with correlation analysis.The best vegetation indices were chosen and the apple canopy chlorophyll content estimation model was established by analyzing vegetation index of two-band combination in the sensitive region 400~1 350 nm.The result showed that (1) The sensitive band region of apple canopy chlorophyll content is 400 ~ 1 350 rm.(2) The vegetation index CCI(D794/D763)can commendably estimate the apple canopy chlorophyll content.(3) The model with CCI(D794/D763)as the independent variables was determined to be the best for chlorophyll content prediction of apple tree canopy.Therefore,using hyperspectral technology can estimate apple canopy chlorophyll content more rapidly and accurately,and provides a theoretical basis for rapid apple tree canopy nutrition diagnosis and growth monitoring.

  7. Detecting phylogenetic breakpoints and discordance from genome-wide alignments for species tree reconstruction.

    Science.gov (United States)

    Ané, Cécile

    2011-01-01

    With the easy acquisition of sequence data, it is now possible to obtain and align whole genomes across multiple related species or populations. In this work, I assess the performance of a statistical method to reconstruct the whole distribution of phylogenetic trees along the genome, estimate the proportion of the genome for which a given clade is true, and infer a concordance tree that summarizes the dominant vertical inheritance pattern. There are two main issues when dealing with whole-genome alignments, as opposed to multiple genes: the size of the data and the detection of recombination breakpoints. These breakpoints partition the genomic alignment into phylogenetically homogeneous loci, where sites within a given locus all share the same phylogenetic tree topology. To delimitate these loci, I describe here a method based on the minimum description length (MDL) principle, implemented with dynamic programming for computational efficiency. Simulations show that combining MDL partitioning with Bayesian concordance analysis provides an efficient and robust way to estimate both the vertical inheritance signal and the horizontal phylogenetic signal. The method performed well both in the presence of incomplete lineage sorting and in the presence of horizontal gene transfer. A high level of systematic bias was found here, highlighting the need for good individual tree building methods, which form the basis for more elaborate gene tree/species tree reconciliation methods. PMID:21362638

  8. Stem CO2 efflux in six co-occurring tree species: underlying factors and ecological implications.

    Science.gov (United States)

    Rodríguez-Calcerrada, Jesús; López, Rosana; Salomón, Roberto; Gordaliza, Guillermo G; Valbuena-Carabaña, María; Oleksyn, Jacek; Gil, Luis

    2015-06-01

    Stem respiration plays a role in species coexistence and forest dynamics. Here we examined the intra- and inter-specific variability of stem CO2 efflux (E) in dominant and suppressed trees of six deciduous species in a mixed forest stand: Fagus sylvatica L., Quercus petraea [Matt.] Liebl, Quercus pyrenaica Willd., Prunus avium L., Sorbus aucuparia L. and Crataegus monogyna Jacq. We conducted measurements in late autumn. Within species, dominants had higher E per unit stem surface area (Es ) mainly because sapwood depth was higher than in suppressed trees. Across species, however, differences in Es corresponded with differences in the proportion of living parenchyma in sapwood and concentration of non-structural carbohydrates (NSC). Across species, Es was strongly and NSC marginally positively related with an index of drought tolerance, suggesting that slow growth of drought-tolerant trees is related to higher NSC concentration and Es . We conclude that, during the leafless period, E is indicative of maintenance respiration and is related with some ecological characteristics of the species, such as drought resistance; that sapwood depth is the main factor explaining variability in Es within species; and that the proportion of NSC in the sapwood is the main factor behind variability in Es among species. PMID:25292455

  9. The Right Tree for the Job? Perceptions of Species Suitability for the Provision of Ecosystem Services

    Science.gov (United States)

    Smaill, Simeon J.; Bayne, Karen M.; Coker, Graham W. R.; Paul, Thomas S. H.; Clinton, Peter W.

    2014-04-01

    Stakeholders in plantation forestry are increasingly aware of the importance of the ecosystem services and non-market values associated with forests. In New Zealand, there is significant interest in establishing species other than Pinus radiata D. Don (the dominant plantation species) in the belief that alternative species are better suited to deliver these services. Significant risk is associated with this position as there is little objective data to support these views. To identify which species were likely to be planted to deliver ecosystem services, a survey was distributed to examine stakeholder perceptions. Stakeholders were asked which of 15 tree attributes contributed to the provision of five ecosystem services (amenity value, bioenergy production, carbon capture, the diversity of native habitat, and erosion control/water quality) and to identify which of 22 candidate tree species possessed those attributes. These data were combined to identify the species perceived most suitable for the delivery of each ecosystem service. Sequoia sempervirens (D.Don) Endl. closely matched the stakeholder derived ideotypes associated with all five ecosystem services. Comparisons to data from growth, physiological and ecological studies demonstrated that many of the opinions held by stakeholders were inaccurate, leading to erroneous assumptions regarding the suitability of most candidate species. Stakeholder perceptions substantially influence tree species selection, and plantations established on the basis of inaccurate opinions are unlikely to deliver the desired outcomes. Attitudinal surveys associated with engagement campaigns are essential to improve stakeholder knowledge, advancing the development of fit-for-purpose forest management that provides the required ecosystem services.

  10. Effects of nurse trees, spacing, and tree species on biomass production in mixed forest plantations

    DEFF Research Database (Denmark)

    Nord-Larsen, Thomas; Meilby, Henrik

    2016-01-01

    in the longterm leading to deciduous stands that are believed to better meet the demands for other ecosystem services. Ten different species combinations were planted, with two different stocking densities, at three different sites in Denmark. Significant differences, with regard to biomass production, were...

  11. Convergent elevation trends in canopy chemical traits of tropical forests.

    Science.gov (United States)

    Asner, Gregory P; Martin, Roberta E

    2016-06-01

    The functional biogeography of tropical forests is expressed in foliar chemicals that are key physiologically based predictors of plant adaptation to changing environmental conditions including climate. However, understanding the degree to which environmental filters sort the canopy chemical characteristics of forest canopies remains a challenge. Here, we report on the elevation and soil-type dependence of forest canopy chemistry among 75 compositionally and environmentally distinct forests in nine regions, with a total of 7819 individual trees representing 3246 species collected, identified and assayed for foliar traits. We assessed whether there are consistent relationships between canopy chemical traits and both elevation and soil type, and evaluated the general role of phylogeny in mediating patterns of canopy traits within and across communities. Chemical trait variation and partitioning suggested a general model based on four interconnected findings. First, geographic variation at the soil-Order level, expressing broad changes in fertility, underpins major shifts in foliar phosphorus (P) and calcium (Ca). Second, elevation-dependent shifts in average community leaf dry mass per area (LMA), chlorophyll, and carbon allocation (including nonstructural carbohydrates) are most strongly correlated with changes in foliar Ca. Third, chemical diversity within communities is driven by differences between species rather than by plasticity within species. Finally, elevation- and soil-dependent changes in N, LMA and leaf carbon allocation are mediated by canopy compositional turnover, whereas foliar P and Ca are driven more by changes in site conditions than by phylogeny. Our findings have broad implications for understanding the global ecology of humid tropical forests, and their functional responses to changing climate.

  12. Convergent elevation trends in canopy chemical traits of tropical forests.

    Science.gov (United States)

    Asner, Gregory P; Martin, Roberta E

    2016-06-01

    The functional biogeography of tropical forests is expressed in foliar chemicals that are key physiologically based predictors of plant adaptation to changing environmental conditions including climate. However, understanding the degree to which environmental filters sort the canopy chemical characteristics of forest canopies remains a challenge. Here, we report on the elevation and soil-type dependence of forest canopy chemistry among 75 compositionally and environmentally distinct forests in nine regions, with a total of 7819 individual trees representing 3246 species collected, identified and assayed for foliar traits. We assessed whether there are consistent relationships between canopy chemical traits and both elevation and soil type, and evaluated the general role of phylogeny in mediating patterns of canopy traits within and across communities. Chemical trait variation and partitioning suggested a general model based on four interconnected findings. First, geographic variation at the soil-Order level, expressing broad changes in fertility, underpins major shifts in foliar phosphorus (P) and calcium (Ca). Second, elevation-dependent shifts in average community leaf dry mass per area (LMA), chlorophyll, and carbon allocation (including nonstructural carbohydrates) are most strongly correlated with changes in foliar Ca. Third, chemical diversity within communities is driven by differences between species rather than by plasticity within species. Finally, elevation- and soil-dependent changes in N, LMA and leaf carbon allocation are mediated by canopy compositional turnover, whereas foliar P and Ca are driven more by changes in site conditions than by phylogeny. Our findings have broad implications for understanding the global ecology of humid tropical forests, and their functional responses to changing climate. PMID:26582427

  13. Genetic variation in a tropical tree species influences the associated epiphytic plant and invertebrate communities in a complex forest ecosystem.

    Science.gov (United States)

    Zytynska, Sharon E; Fay, Michael F; Penney, David; Preziosi, Richard F

    2011-05-12

    Genetic differences among tree species, their hybrids and within tree species are known to influence associated ecological communities and ecosystem processes in areas of limited species diversity. The extent to which this same phenomenon occurs based on genetic variation within a single tree species, in a diverse complex ecosystem such as a tropical forest, is unknown. The level of biodiversity and complexity of the ecosystem may reduce the impact of a single tree species on associated communities. We assessed the influence of within-species genetic variation in the tree Brosimum alicastrum (Moraceae) on associated epiphytic and invertebrate communities in a neotropical rainforest. We found a significant positive association between genetic distance of trees and community difference of the epiphytic plants growing on the tree, the invertebrates living among the leaf litter around the base of the tree, and the invertebrates found on the tree trunk. This means that the more genetically similar trees are host to more similar epiphyte and invertebrate communities. Our work has implications for whole ecosystem conservation management, since maintaining sufficient genetic diversity at the primary producer level will enhance species diversity of other plants and animals.

  14. Radial variation in sap flow in five laurel forest tree species in Tenerife, Canary Islands.

    Science.gov (United States)

    Jiménez, M. Soledad; Nadezhdina, Nadezhda; Cermák, Jan; Morales, Domingo

    2000-11-01

    Variations in radial patterns of xylem water content and sap flow rate were measured in five laurel forest tree species (Laurus azorica (Seub.) Franco, Persea indica (L.) Spreng., Myrica faya Ait., Erica arborea L. and Ilex perado Ait. ssp. platyphylla (Webb & Berth.) Tutin) growing in an experimental plot at Agua García, Tenerife, Canary Islands. Measurements were performed around midday during warm and sunny days by the heat field deformation method. In all species, water content was almost constant (around 35% by volume) over the whole xylem cross-sectional area. There were no differences in wood color over the whole cross-sectional area of the stem in most species with the exception of E. arborea, whose wood became darker in the inner layers. Radial patterns of sap flow were highly variable and did not show clear relationships with tree diameter or species. Sap flow occurred over the whole xylem cross-sectional area in some species, whereas it was limited to the outer xylem layers in others. Sap flow rate was either similar along the xylem radius or exhibited a peak in the outer part of the xylem area. Low sap flow rates with little variation in radial pattern were typical for shaded suppressed trees, whereas dominant trees exhibited high sap flow rates with a peak in the radial pattern. Stem damage resulted in a significant decrease in sap flow rate in the outer xylem layers. The outer xylem is more important for whole tree water supply than the inner xylem because of its larger size. We conclude that measurement of radial flow pattern provides a reliable method of integrating sap flow from individual measuring points to the whole tree.

  15. A Section-based Method For Tree Species Classification Using Airborne LiDAR Discrete Points In Urban Areas

    Science.gov (United States)

    Chunjing, Y. C.; Hui, T.; Zhongjie, R.; Guikai, B.

    2015-12-01

    As a new approach to forest inventory utilizing, LiDAR remote sensing has become an important research issue in the past. Lidar researches initially concentrate on the investigation for mapping forests at the tree level and identifying important structural parameters, such as tree height, crown size, crown base height, individual tree species, and stem volume etc. But for the virtual city visualization and mapping, the traditional methods of tree classification can't satisfy the more complex conditions. Recently, the advanced LiDAR technology has generated new full waveform scanners that provide a higher point density and additional information about the reflecting characteristics of trees. Subsequently, it was demonstrated that it is feasible to detect individual overstorey trees in forests and classify species. But the important issues like the calibration and the decomposition of full waveform data with a series of Gaussian functions usually take a lot of works. What's more, the detection and classification of vegetation results relay much on the prior outcomes. From all above, the section-based method for tree species classification using small footprint and high sampling density lidar data is proposed in this paper, which can overcome the tree species classification issues in urban areas. More specific objectives are to: (1)use local maximum height decision and four direction sections certification methods to get the precise locations of the trees;(2) develop new lidar-derived features processing techniques for characterizing the section structure of individual tree crowns;(3) investigate several techniques for filtering and analyzing vertical profiles of individual trees to classify the trees, and using the expert decision skills based on percentile analysis;(4) assess the accuracy of estimating tree species for each tree, and (5) investigate which type of lidar data, point frequency or intensity, provides the most accurate estimate of tree species

  16. Air pollution and the respiration of certain tree species

    Energy Technology Data Exchange (ETDEWEB)

    Makedonska, T.; Slavova, V.

    1973-01-01

    These studies are conducted to compare the effects of air pollution on horse chestnut (Aesculus hippocastanum L.), London plane (Platanus acerifolia Milld.) ash-leaved maple (Acer negundo L.) and European birch (Betula alba L.). With increasing concentrations of air pollution these species react by increasing the intensity of respiration, as in separate cases the increase reaches up to 40%. Most sensitive to air pollution is the horse chestnut, followed by birch and ash-leaved maple; least sensitive is London plane. With respect to gas resistance birch and ash-leaved maple rank close to the horse chestnut but are more resistant than the horse chestnut and less sensitive than London plane.

  17. Certified and Uncertified Logging Concessions Compared in Gabon: Changes in Stand Structure, Tree Species, and Biomass

    Science.gov (United States)

    Medjibe, V. P.; Putz, Francis E.; Romero, Claudia

    2013-03-01

    Forest management certification is assumed to promote sustainable forest management, but there is little field-based evidence to support this claim. To help fill this gap, we compared a Forest Stewardship Council (FSC)-certified with an adjacent uncertified, conventionally logged concession (CL) in Gabon on the basis of logging damage, above-ground biomass (AGB), and tree species diversity and composition. Before logging, we marked, mapped, and measured all trees >10 cm dbh in 20 and twelve 1-ha permanent plots in the FSC and CL areas, respectively. Soil and tree damage due to felling, skidding, and road-related activities was then assessed 2-3 months after the 508 ha FSC study area and the 200 ha CL study area were selectively logged at respective intensities of 5.7 m3/ha (0.39 trees/ha) and 11.4 m3/ha (0.76 trees/ha). For each tree felled, averages of 9.1 and 20.9 other trees were damaged in the FSC and CL plots, respectively; when expressed as the impacts per timber volume extracted, the values did not differ between the two treatments. Skid trails covered 2.9 % more of the CL surface, but skid trail length per unit timber volume extracted was not greater. Logging roads were wider in the CL than FSC site and disturbed 4.7 % more of the surface. Overall, logging caused declines in AGB of 7.1 and 13.4 % at the FSC and CL sites, respectively. Changes in tree species composition were small but greater for the CL site. Based on these findings and in light of the pseudoreplicated study design with less-than perfect counterfactual, we cautiously conclude that certification yields environmental benefits even after accounting for differences in logging intensities.

  18. Patterns of tree buttressing at Lawachara National Park, Bangladesh

    Institute of Scientific and Technical Information of China (English)

    Md. Abu Hanifa Mehedi; Chandan Kundu; Md. Qumruzzaman Chowdhury

    2012-01-01

    We describe patterns of buttress formation and development in eleven tree species at Lawachara National Park,Bangladesh.Forty-five percent of trees of these 11 species had buttresses.Artocarpus chaplasha Roxb.showed maximum (87%) buttress formation,whereas Alstonia scholaris (L.) R.Br.did not show any buttress.Buttresses were recorded in 20%-40% of trees of six species and 40%-60% of trees in three species.Mean length and height of buttress varied among the species and ranged from 0.37-1.37 m and 0.71-2.13 m,respectively.Buttress height,mean buttress length,total buttress length,and total length plus length of secondaries increased with DBH (diameter at breast height) and tree height.Buttress number did not increase with DBH or tree height.Under-storey and mid-canopy trees produced less developed buttresses than did emergent trees (p<0.01).Wood density showed moderate effects on buttress characters (p<0.05),while the slope of the land did not.Canopy category was a primary regulating factor for tree buttressing,suggesting that buttresses are mechanical adaptations of trees to counter physical stresses.

  19. Tree species specific soil moisture patterns and dynamics through the seasons

    Science.gov (United States)

    Heidbüchel, Ingo; Dreibrodt, Janek; Simard, Sonia; Güntner, Andreas; Blume, Theresa

    2015-04-01

    Soil moisture patterns in the landscape are largely controlled by soil types (pore size distributions) and landscape position. But how strong is the influence of vegetation on patterns within a single soil type? While we would envision a clear difference in soil moisture patterns and responses between for example bare soil, a pasture and a forest, our conceptual images start to become less clear when we move on to different forest stands. Do different tree species cause different moisture patterns to emerge? Could it be possible to identify the dominant tree species of a site by classifying its soil moisture pattern? To investigate this question we analyzed data from 15 sensor clusters in the lowlands of north-eastern Germany (within the TERENO observatory) which were instrumented with soil moisture sensors (5 profiles per site), tensiometers, sap flow sensors, throughfall and stemflow gages. Data has been collected at these sites since May 2014. While the summer data has already been analyzed, the analysis of the winter data and thus the possible seasonal shifts in patterns will be carried out in the coming months. Throughout the last summer we found different dynamics of soil moisture patterns under pine trees compared to beech trees. While the soils under beech trees were more often relatively wet and more often relatively dry, the soils under pine trees showed less variability and more often average soil moisture. These differences are most likely due to differences in both throughfall patterns as well as root water uptake. Further analysis includes the use of throughfall and stemflow data as well as stable water isotope samples that were taken at different depths in the soil, in the groundwater and from the sapwood. The manifestation of tree species differences in soil moisture patterns and dynamics is likely to have implications for groundwater recharge, transit times and hydrologic partitioning.

  20. Influences of calcium availability and tree species on Ca isotope fractionation in soil and vegetation

    Science.gov (United States)

    Page, B.D.; Bullen, T.D.; Mitchell, M.J.

    2008-01-01

    The calcium (Ca) isotope system is potentially of great use for understanding biogeochemical processes at multiple scales in forest ecosystems, yet remains largely unexplored for this purpose. In order to further our understanding of Ca behavior in forests, we examined two nearly adjacent hardwood-dominated catchments with differing soil Ca concentrations, developed from crystalline bedrock, to determine the variability of 44Ca/ 40Ca ratios (expressed as ??44Ca) within soil and vegetation pools. For both sugar maple and American beech, the Ca isotope compositions of the measured roots and calculated bulk trees were considerably lighter than those of soil pools at these sites, suggesting that the trees were able to preferentially take up light Ca at the root-soil interface. The Ca isotope compositions of three of four root samples were among the lightest values yet reported for terrestrial materials (??44Ca ???-3.95???). Our results further indicate that Ca isotopes were fractionated along the transpiration streams of both tree species with roots having the least ??44Ca values and leaf litter the greatest. An approximately 2??? difference in ??44Ca values between roots and leaf litter of both tree species suggests a persistent fractionation mechanism along the transpiration stream, likely related to Ca binding in wood tissue coupled with internal ion exchange. Finally, our data indicate that differing tree species demand for Ca and soil Ca concentrations together may influence Ca isotope distribution within the trees. Inter-catchment differences in Ca isotope distributions in soils and trees were minor, indicating that the results of our study may have broad transferability to studies of forest ecosystems in catchments developed on crystalline substrates elsewhere. ?? 2008 Springer Science+Business Media B.V.

  1. Patterns of tree species diversity in relation to climatic factors on the Sierra Madre Occidental, Mexico.

    Directory of Open Access Journals (Sweden)

    Ramón Silva-Flores

    Full Text Available Biological diversity can be defined as variability among living organisms from all sources, including terrestrial organisms, marine and other aquatic ecosystems, and the ecological complexes which they are part of. This includes diversity within species, between species, and of ecosystems. Numerous diversity indices combine richness and evenness in a single expression, and several climate-based explanations have been proposed to explain broad-scale diversity patterns. However, climate-based water-energy dynamics appears to be an essential factor that determines patterns of diversity. The Mexican Sierra Madre Occidental occupies an area of about 29 million hectares and is located between the Neotropical and Holarctic ecozones. It shelters a high diversity of flora, including 24 different species of Pinus (ca. 22% on the whole, 54 species of Quercus (ca. 9-14%, 7 species of Arbutus (ca. 50% and many other trees species. The objectives of this study were to model how tree species diversity is related to climatic and geographic factors and stand density and to test the Metabolic Theory, Productivity-Diversity Hypothesis, Physiological Tolerance Hypothesis, Mid-Domain Effect, and the Water-Energy Dynamic Theory on the Sierra Madre Occidental, Durango. The results supported the Productivity-Diversity Hypothesis, Physiological Tolerance Hypothesis and Water-Energy Dynamic Theory, but not the Mid-Domain Effect or Metabolic Theory. The annual aridity index was the variable most closely related to the diversity indices analyzed. Contemporary climate was found to have moderate to strong effects on the minimum, median and maximum tree species diversity. Because water-energy dynamics provided a satisfactory explanation for the patterns of minimum, median and maximum diversity, an understanding of this factor is critical to future biodiversity research. Quantile regression of the data showed that the three diversity parameters of tree species are generally

  2. Woody species recruitment under monospecific plantations of pioneer trees - facilitation or inhibition?

    Directory of Open Access Journals (Sweden)

    Trindade DFV

    2012-02-01

    Full Text Available The successional model of forest restoration is based on the facilitation process, in which the establishment of pioneer tree species favors the late successional tree species. We tested the hypothesis of facilitation through a case study, comparing tree species diversity in the understory of two Neotropical native tree species plantations, Trema micrantha (L. Blüme (Cannabaceae and Schinus molle L. (Anacardiaceae. Results obtained under the plantations were compared with an adjacent area under spontaneous secondary succession, analyzing the ligneous plant diversity, soil physic-chemistry and shading. Additionally, the seed rain under the two plantations was analyzed. The area of spontaneous secondary succession and the area with T. micrantha had the highest ligneous plant diversity. The understory of T. micrantha plantation had the lowest light intensity and higher late successional species abundance. In addition, T. micrantha had higher plant diversity than S. molle, which could be explained at least partially by higher diversity in the seed rain. Higher litterfall and mineral content of leaves and twigs of T. micrantha did not coincide with higher topsoil mineral content under that species. Instead, soil under S. molle had higher level of P than the soil under T. micrantha. Data suggest that a high diversity of ligneous plants could be thrived by the spontaneous succession. On the other hand, T. micrantha had promoted a higher richness and abundance of late successional species, which could be related to a more pronounced shade effect, in agreement with the facilitation conception. The lowest diversity and density of ligneous plant species under S. molle characterizes an inhibition effect. T. micrantha could be included in restoration plans assembled with other species or combined with areas without intervention, whenever the spontaneous regeneration is possible.

  3. Environmental niche and distribution of six deciduous tree species in the Spanish Atlantic region

    Directory of Open Access Journals (Sweden)

    Roces-Díaz JV

    2015-04-01

    Full Text Available Understanding the influence of environmental factors on the distribution of tree species is essential for developing management actions at regional level. We computed species distribution models for six European tree species to determine their potential niche in the Spanish Atlantic region, where deciduous forests are relatively well preserved. We used data from the national Forest Inventory and topo-climatic and soil variables to construct distribution models by the Generalized Linear Model procedure. The main factors found to determine the presence of the selected species were minimum winter temperature and mineral fertility of soils. Suitable habitats for Quercus petraea and F. sylvatica were mainly high-altitude areas with low minimum temperatures. In contrast, Q. robur and C. sativa were restricted to low altitudes and warmer conditions. Betula pubescens was not influenced by the elevation, probably because it is adapted to Atlantic conditions, and distribution of this species was associated with low fertility soils. Although the submediterranean Q. pyrenaica was positively influenced by the slope, model performance was poor for this species, possibly because of the truncated environmental range of the species in the study area. The findings suggest that temperature rather than moisture is shaping the distribution of deciduous trees at the southern limit of the Atlantic biogeographic region. We also note that the strong elevational difference between the warm coast and the cold mountains may determine the geographical disjunction between Q. robur and Q. petraea in southern Europe.

  4. Data concatenation, Bayesian concordance and coalescent-based analyses of the species tree for the rapid radiation of Triturus newts.

    Directory of Open Access Journals (Sweden)

    Ben Wielstra

    Full Text Available The phylogenetic relationships for rapid species radiations are difficult to disentangle. Here we study one such case, namely the genus Triturus, which is composed of the marbled and crested newts. We analyze data for 38 genetic markers, positioned in 3-prime untranslated regions of protein-coding genes, obtained with 454 sequencing. Our dataset includes twenty Triturus newts and represents all nine species. Bayesian analysis of population structure allocates all individuals to their respective species. The branching patterns obtained by data concatenation, Bayesian concordance analysis and coalescent-based estimations of the species tree differ from one another. The data concatenation based species tree shows high branch support but branching order is considerably affected by allele choice in the case of heterozygotes in the concatenation process. Bayesian concordance analysis expresses the conflict between individual gene trees for part of the Triturus species tree as low concordance factors. The coalescent-based species tree is relatively similar to a previously published species tree based upon morphology and full mtDNA and any conflicting internal branches are not highly supported. Our findings reflect high gene tree discordance due to incomplete lineage sorting (possibly aggravated by hybridization in combination with low information content of the markers employed (as can be expected for relatively recent species radiations. This case study highlights the complexity of resolving rapid radiations and we acknowledge that to convincingly resolve the Triturus species tree even more genes will have to be consulted.

  5. Global to local genetic diversity indicators of evolutionary potential in tree species within and outside forests

    DEFF Research Database (Denmark)

    Graudal, Lars; Aravanopoulos, Filippos; Bennadji, Zohra;

    2014-01-01

    -monitoring schemes. Here, we provide a review and an assessment of the different attempts made to provide such indicators for tree genetic diversity from the global level down to the level of the management unit. So far, no generally accepted indicators have been provided as international standards, nor tested...... distributions (patterns of genetic variation of key adaptive traits in the ecological space) of selected species is a realistic way of assessing the trend of intra-specific variation, and thus provides a state indicator of tree genetic diversity also able to reflect possible pressures threatening genetic...... independently of state indicators. A coherent set of indicators covering diversity-productivity-knowledge-management based on the genecological approach is proposed for application on appropriate groups of tree species in the wild and in cultivation worldwide. These indicators realistically reflect the state...

  6. Fine-scale spatial genetic structure of eight tropical tree species as analysed by RAPDs.

    Science.gov (United States)

    Degen, B; Caron, H; Bandou, E; Maggia, L; Chevallier, M H; Leveau, A; Kremer, A

    2001-10-01

    The fine-scale spatial genetic structure of eight tropical tree species (Chrysophyllum sanguinolentum, Carapa procera, Dicorynia guianensis, Eperua grandiflora, Moronobea coccinea, Symphonia globulifera, Virola michelii, Vouacapoua americana) was studied in populations that were part of a silvicultural trial in French Guiana. The species analysed have different spatial distribution, sexual system, pollen and seed dispersal agents, flowering phenology and environmental demands. The spatial position of trees and a RAPD data set for each species were combined using a multivariate genetic distance method to estimate spatial genetic structure. A significant spatial genetic structure was found for four of the eight species. In contrast to most observations in temperate forests, where spatial structure is not usually detected at distances greater than 50 m, significant genetic structure was found at distances up to 300 m. The relationships between spatial genetic structure and life history characteristics are discussed. PMID:11737299

  7. Calorific values of twelve forest tree species growing in Sri Lanka

    Energy Technology Data Exchange (ETDEWEB)

    Steinbeck, K.; Wijesinghe, M.T.J.P.

    1985-01-01

    Calorific values were determined on 1-g samples taken from each of 2 increment cores collected from 3 trees of each species in Oct-Nov 1981. Most trees were growing in plantations and varied in age from 7 to 25 yr. The average calorific content varied by less than 11% between species, ranging from 4683 cal/g for Eucalyptus alba to 5225 cal/g for Pinus caribaea. Calorific contents in the 12 species decreased in the following order: P. caribaea, Tectona grandis, Cupressus macrocarpa, Gmelina arborea, E. microcorys, E. tereticornis, Casuarina equisetifolia, E. grandis, E. camaldulensis, Acacia decurrens, Albizia moluccana and E. alba. It is concluded that there is little value in choosing appropriate species for fuelwood plantations based on wood calorific values. 4 references.

  8. 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.

  9. Dominance and diversity studies of tree species in lesser Himalayan forest of Uttarakhand, India

    Directory of Open Access Journals (Sweden)

    A.S. BISHT

    2016-04-01

    Full Text Available Abstract. Bisht AS, Bhatt AB. 2016. Dominance and diversity studies of tree species in lesser Himalayan forest of Uttarakhand, India. Biodiversitas 17: 70-77. For the present investigation single mountain, approach was applied. This is a supplement the basic approach and extends the gradients further downward in to the forest belt. Vegetational analysis of nine stands covering all the four aspects of the study site of Pauri Garhwal district of Uttarakhand, India has been undertaken. In seven trees, species were encountered. East aspect is characteristics by highest density of Cupressus torulosa while west aspect comprised of Cedrus deodara, Myrica esculenta, Pinus. roxbugrhii, Quercus. leucotrichophora and Rhododendron arboreum, i.e. high diversity with low dominance Cupressus torulosa and Cedrus deodara dominated the north aspect. In general, influence of higher anthropogenic pressure on Quercus species is an important factor for leads to gradual replacement of oak species by Pinus roxburghii in all the aspects.

  10. Disturbance Level Determines the Regeneration of Commercial Tree Species in the Eastern Amazon

    NARCIS (Netherlands)

    Schwartz, G.; Lopes, J.C.; Kanashiro, M.; Mohren, G.M.J.; Pena Claros, M.

    2014-01-01

    The effects of reduced-impact logging (RIL) on the regeneration of commercial tree species were investigated, as long-term timber yields depend partly on the availability of seedlings in a managed forest. On four occasions during a 20-month period in the Tapajós National Forest (Eastern Amazon, Braz

  11. Leaf traits and herbivory rates of tropical tree species differing in successional status.

    NARCIS (Netherlands)

    Poorter, L.; Plassche, van de M.; Willems, S.; Boot, R.G.A.

    2004-01-01

    We evaluated leaf characteristics and herbivory intensities for saplings of fifteen tropical tree species differing in their successional position. Eight leaf traits were selected, related to the costs of leaf display (specific leaf area [SLA], water content), photosynthesis (N and P concentration p

  12. Response of seedlings of different tree species to elevated C02 in Changbai Mountain

    Institute of Scientific and Technical Information of China (English)

    DAILi-min; JILan-zhu; WANGMiao; LIQiu-rong

    2003-01-01

    Eco-physiological responses of seedlings of eight species, Pinus koraiensis, Picea koraiensis, Lanx olgensis,Populus ussuriensis, Betula platyphylla, Tilia amurensis, Traxinus mandshurica and Acer mono from broadleaved/Korean pine forest, to elevated CO2 were studied by using open-top chambers under natural sunlight in Changbai Mountain, China in two growing seasons (1998-1999). Two concentrations of CO2 were designed: elevated CO2 (700 pmol· mol-1) and ambient CO2 (400μmol· mol-1). The study results showed that the height growth of the tree seedlings grown at elevated CO2 increased by about 10%-40% compared to those grown at ambient CO2. And the water using efficiency of seedlings also followed the same tendency. However, the responses of seedlings in transpiration and chlorophyll content to elevated CO2 varied with tree species.The broad-leaf tree species were more sensitive to the elevated CO2than conifer tree species. All seedlings showed a photo-synthetic acclimation to Iong-term elevated CO2.

  13. Morphological Characterization of African Bush Mango trees (Irvingia species) in the Dahomey Gap (West Africa)

    NARCIS (Netherlands)

    Vihotogbe, R.; Berg, van den R.G.; Sosef, M.S.M.

    2013-01-01

    The variation of the morphological characters of bitter and sweet African bush mango trees (Irvingia species) was investigated in the Dahomey Gap which is the West African savannah woodland area separating the Upper and the Lower Guinean rain forest blocks. African bush mangoes have been rated as th

  14. Estimating the global conservation status of more than 15,000 Amazonian tree species

    DEFF Research Database (Denmark)

    ter Steege, Hans; Pitman, Nigel C. A.; Killeen, Timothy J.;

    2015-01-01

    Estimates of extinction risk for Amazonian plant and animal species are rare and not often incorporated into land-use policy and conservation planning. We overlay spatial distribution models with historical and projected deforestation to show that at least 36% and up to 57% of all Amazonian tree ...

  15. Coniochaeta (Lecythophora), Collophora gen. nov and Phaeomoniella species associated with wood necroses of Prunus trees

    NARCIS (Netherlands)

    Damm, U.; Fourie, P.H.; Crous, P.W.

    2010-01-01

    Species of the genus Coniochaeta (anamorph: Lecythophora) are known as pathogens of woody hosts, but can also cause opportunistic human infections. Several fungi with conidial stages resembling Lecythophora were isolated from necrotic wood samples of Prunus trees in South Africa. In order to reveal

  16. Coniochaeta (Lecythophora), Collophora gen. nov. And Phaeomoniella species associated with wood necroses of Prunus trees

    NARCIS (Netherlands)

    Damm, U.; Fourie, P.H.; Crous, P.W.

    2010-01-01

    Species of the genus Coniochaeta (anamorph: Lecythophora) are known as pathogens of woody hosts, but can also cause opportunistic human infections. Several fungi with conidial stages resembling Lecythophora were isolated from necrotic wood samples of Prunus trees in South Africa. In order to reveal

  17. Coniochaeta (Lecythophora), Collophora gen. nov. and Phaeomoniella species associated with wood necroses of Prunus trees

    NARCIS (Netherlands)

    Damm, U.; Fourie, P.H.; Crous, P.W.

    2010-01-01

    Species of the genus Coniochaeta (anamorph: Lecythophora) are known as pathogens of woody hosts, but can also cause opportunistic human infections. Several fungi with conidial stages resembling Lecythophora were isolated from necrotic wood samples of Prunus trees in South Africa. In order to reveal

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

    NARCIS (Netherlands)

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

    2003-01-01

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

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

    NARCIS (Netherlands)

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

    2003-01-01

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

  20. Functional traits, drought performance, and the distribution of tree species in tropical forests of Ghana

    NARCIS (Netherlands)

    Amissah, L.

    2014-01-01

      Tropical forests occur along a rainfall gradient where annual amount, the length and intensity of dry season vary and water availability shapes therefore strongly the distribution of tree species. Annual rainfall in West Africa has declined at a rate of 4% per decade, and climate change model

  1. New flux based dose-response relationships for ozone for European forest tree species.

    Science.gov (United States)

    Büker, P; Feng, Z; Uddling, J; Briolat, A; Alonso, R; Braun, S; Elvira, S; Gerosa, G; Karlsson, P E; Le Thiec, D; Marzuoli, R; Mills, G; Oksanen, E; Wieser, G; Wilkinson, M; Emberson, L D

    2015-11-01

    To derive O3 dose-response relationships (DRR) for five European forest trees species and broadleaf deciduous and needleleaf tree plant functional types (PFTs), phytotoxic O3 doses (PODy) were related to biomass reductions. PODy was calculated using a stomatal flux model with a range of cut-off thresholds (y) indicative of varying detoxification capacities. Linear regression analysis showed that DRR for PFT and individual tree species differed in their robustness. A simplified parameterisation of the flux model was tested and showed that for most non-Mediterranean tree species, this simplified model led to similarly robust DRR as compared to a species- and climate region-specific parameterisation. Experimentally induced soil water stress was not found to substantially reduce PODy, mainly due to the short duration of soil water stress periods. This study validates the stomatal O3 flux concept and represents a step forward in predicting O3 damage to forests in a spatially and temporally varying climate. PMID:26164201

  2. White Birch Trees as Resource Species of Russia : Their Distribution, Ecophysiological Features, Multiple Utilizations

    OpenAIRE

    Zyryanova, Olga A.; TERAZAWA, Minoru; KOIKE, TAKAYOSHI; Zyryanov, Vyacheslav I.

    2010-01-01

    Four birch tree species (Betula costata, B. pendula, B. platyphylla, B. pubescens) are traditionally important resource species in Russia. In the article, we discuss their spatial and ecophysiological features, biochemical constituents of the living tissues of the birches such as the wood, outer and inner bark, twigs, leaves, buds, roots. The exudation, tapping periods and sap productivity, exudated birch sap and derived birch tar are also reviewed. We show numerous useful wooden, medicinal, ...

  3. Estimating the global conservation status of more than 15,000 Amazonian tree species

    OpenAIRE

    H. ter Steege; Pitman, NC; Killeen, TJ; Laurance, WF; Peres, CA; Guevara, JE; Salomão, RP; Castilho, CV; Amaral, IL; de Almeida Matos, FD; de Souza Coelho, L; Magnusson, WE; Phillips, OL; de Andrade Lima Filho, D; de Jesus Veiga Carim, M

    2015-01-01

    Estimates of extinction risk for Amazonian plant and animal species are rare and not often incorporated into land-use policy and conservation planning. We overlay spatial distribution models with historical and projected deforestation to show that at least 36% and up to 57% of all Amazonian tree species are likely to qualify as globally threatened under International Union for Conservation of Nature (IUCN) Red List criteria. If confirmed, these results would increase the number of threatened ...

  4. Estimating the global conservation status of more than 15,000 Amazonian tree species.

    OpenAIRE

    H. ter Steege; Pitman, NC; Killeen, TJ; Laurance, WF; Peres, CA; Guevara, JE; Salomão, RP; Castilho, CV; Amaral, IL; de Almeida Matos, FD; de Souza Coelho, L; Magnusson, WE; Phillips, OL; de Andrade Lima Filho, D; de Jesus Veiga Carim, M

    2015-01-01

    Estimates of extinction risk for Amazonian plant and animal species are rare and not often incorporated into land-use policy and conservation planning. We overlay spatial distribution models with historical and projected deforestation to show that at least 36% and up to 57% of all Amazonian tree species are likely to qualify as globally threatened under International Union for Conservation of Nature (IUCN) Red List criteria. If confirmed, these results would increase the number of threatened ...

  5. Early Growth Assessment of Selected Exotic and Indigenous Tree Species in Nigeria

    Directory of Open Access Journals (Sweden)

    Alfred Ossai Onefeli

    2014-06-01

    Full Text Available Background and Purpose: Nigeria is greatly endowed with numerous tree species of which majority of them are native while few are exotic. Report shows that high percentage of man-made forests in the country is dominated with exotic species. This culminated from the assumption that exotic trees are fast growing. However, this study investigated the growth of indigenous trees in tandem with that of exotic species with a purpose to clarify the assumption about the growth and conservation of indigenous species in natural forests. Materials and Methods: The study was conducted at the nursery unit of the Department of Forest Resources Management, University of Ibadan, Nigeria. Five (5 different one year old tree species seedlings were used for the study. Two of the species (Tectona grandis and Gmelina arborea are exotic while the other three species (Khaya senegalensis, Khaya grandifolia and Afzelia africana are native to Nigeria. They were planted on the field in a completely random design and then replicated eight times. Data were collected every month on their height growth, collar diameter and leaf number. Data obtained were subsequently analyzed with ANOVA. Results and Conclusions: Results show that K. grandifolia (45.39 cm grew significantly better (p<0.05 in height than G. arborea (38.11 cm and T. grandis (22.36 cm, while A. africana (40.03 cm closely followed K. grandifolia. Based on the results, the selected indigenous species displayed promising potentials for conservation purpose. Hence, further research in this aspect is encouraged to confirm the findings.

  6. A new species in the tree genus Polyceratocarpus (Annonaceae) from the Udzungwa Mountains of Tanzania

    OpenAIRE

    Marshall, Andrew R.; Couvreur, Thomas L. P.; Summers, Abigail L.; Deere, Nicolas J.; Luke, W.R. Quentin; Ndangalasi, Henry J.; Sparrow, Sue; Johnson, David M.

    2016-01-01

    Polyceratocarpus askhambryan-iringae, an endemic tree species of Annonaceae from the Udzungwa Mountains of Tanzania, is described and illustrated. The new species is identified as a member of the genus Polyceratocarpus by the combination of staminate and bisexual flowers, axillary inflorescences, subequal outer and inner petals, and multi-seeded monocarps with pitted seeds. From P. scheffleri, with which it has previously been confused, it differs in the longer pedicels, smaller and thinner p...

  7. Narrowing historical uncertainty: probabilistic classification of ambiguously identified tree species in historical forest survey data

    Science.gov (United States)

    2002-01-01

    Historical data have increasingly become appreciated for insight into the past conditions of ecosystems. Uses of such data include assessing the extent of ecosystem change; deriving ecological baselines for management, restoration, and modeling; and assessing the importance of past conditions on the composition and function of current systems. One historical data set of this type is the Public Land Survey (PLS) of the United States General Land Office, which contains data on multiple tree species, sizes, and distances recorded at each survey point, located at half-mile (0.8 km) intervals on a 1-mi (1.6 km) grid. This survey method was begun in the 1790s on US federal lands extending westward from Ohio. Thus, the data have the potential of providing a view of much of the US landscape from the mid-1800s, and they have been used extensively for this purpose. However, historical data sources, such as those describing the species composition of forests, can often be limited in the detail recorded and the reliability of the data, since the information was often not originally recorded for ecological purposes. Forest trees are sometimes recorded ambiguously, using generic or obscure common names. For the PLS data of northern Wisconsin, USA, we developed a method to classify ambiguously identified tree species using logistic regression analysis, using data on trees that were clearly identified to species and a set of independent predictor variables to build the models. The models were first created on partial data sets for each species and then tested for fit against the remaining data. Validations were conducted using repeated, random subsets of the data. Model prediction accuracy ranged from 81% to 96% in differentiating congeneric species among oak, pine, ash, maple, birch, and elm. Major predictor variables were tree size, associated species, landscape classes indicative of soil type, and spatial location within the study region. Results help to clarify ambiguities

  8. The Trichoptera barcode initiative: a strategy for generating a species-level Tree of Life.

    Science.gov (United States)

    Zhou, Xin; Frandsen, Paul B; Holzenthal, Ralph W; Beet, Clare R; Bennett, Kristi R; Blahnik, Roger J; Bonada, Núria; Cartwright, David; Chuluunbat, Suvdtsetseg; Cocks, Graeme V; Collins, Gemma E; deWaard, Jeremy; Dean, John; Flint, Oliver S; Hausmann, Axel; Hendrich, Lars; Hess, Monika; Hogg, Ian D; Kondratieff, Boris C; Malicky, Hans; Milton, Megan A; Morinière, Jérôme; Morse, John C; Mwangi, François Ngera; Pauls, Steffen U; Gonzalez, María Razo; Rinne, Aki; Robinson, Jason L; Salokannel, Juha; Shackleton, Michael; Smith, Brian; Stamatakis, Alexandros; StClair, Ros; Thomas, Jessica A; Zamora-Muñoz, Carmen; Ziesmann, Tanja; Kjer, Karl M

    2016-09-01

    DNA barcoding was intended as a means to provide species-level identifications through associating DNA sequences from unknown specimens to those from curated reference specimens. Although barcodes were not designed for phylogenetics, they can be beneficial to the completion of the Tree of Life. The barcode database for Trichoptera is relatively comprehensive, with data from every family, approximately two-thirds of the genera, and one-third of the described species. Most Trichoptera, as with most of life's species, have never been subjected to any formal phylogenetic analysis. Here, we present a phylogeny with over 16 000 unique haplotypes as a working hypothesis that can be updated as our estimates improve. We suggest a strategy of implementing constrained tree searches, which allow larger datasets to dictate the backbone phylogeny, while the barcode data fill out the tips of the tree. We also discuss how this phylogeny could be used to focus taxonomic attention on ambiguous species boundaries and hidden biodiversity. We suggest that systematists continue to differentiate between 'Barcode Index Numbers' (BINs) and 'species' that have been formally described. Each has utility, but they are not synonyms. We highlight examples of integrative taxonomy, using both barcodes and morphology for species description.This article is part of the themed issue 'From DNA barcodes to biomes'. PMID:27481793

  9. Tree and tree-like species of Mexico: gymnosperms, monocotyledons, and tree ferns Especies arbóreas y arborescentes de México: gimnospermas, monocotiledóneas y helechos arborescentes

    OpenAIRE

    Martin Ricker; Hernández, Héctor M.

    2010-01-01

    Trees or tree-like plants are defined here broadly as perennial, self-supporting plants with an adult height of at least 5 m (without ascending leaves or inflorescences), and with 1 or several erect stems with a diameter of at least 10 cm. We present an updated list of all Mexican tree species under that definition in the Gymnospermae (86 species, 38% endemic to Mexico), Monocotyledonae (75 species, 55% endemic), and Pteridophyta (9 species, none endemic). The list contains a total of 170 spe...

  10. Large difference of inhibitive effect of nitrogen deposition on soil methane oxidation between plantations with N-fixing tree species and non-N-fixing tree species

    Science.gov (United States)

    Zhang, Wei; Zhu, Xiaomin; Liu, Lei; Fu, Shenglei; Chen, Hao; Huang, Juan; Lu, Xiankai; Liu, Zhanfeng; Mo, Jiangming

    2012-12-01

    The responses of soil methane (CH4) net fluxes to nitrogen (N) addition in a N-fixing tree species (Acacia auriculiformis (AA)) and a non-N-fixing tree species (Eucalyptus citriodora (EU)) plantation were studied in southern China. Treatments were conducted at each plantation with three N levels (0, 50, and 100 kg N ha-1 yr-1 for control, medium-N, and high-N treatment, respectively, abbreviated as C, MN, and HN). From August 2010 to July 2011, CH4 flux was measured biweekly using a static chamber and gas chromatography technique. The soils of both sites acted as sink of atmospheric CH4. The CH4 uptake rate in control of the AA site (36.3 ± 3.2 μg CH4-C m-2 h-1) was greater than that of the EU plantation (29.9 ± 0.9 μg CH4-C m-2 h-1). In the AA plantation, the averaged rates of CH4 uptake for the MN (28.6 ± 2.3 μg CH4-C m-2 h-1) and HN treatment (23.8 ± 2.8 μg CH4-C m-2 h-1) were decreased by 21% and 35%, respectively, compared to the control. However, there was no change of soil CH4 uptake between N-treated plots and the controls in the EU site. Our results indicated that there might be large difference of inhibitive effect of N deposition on soil CH4 oxidation between the AA and EU plantations. The projected increase of N deposition would weaken the capability of N-fixing tree species plantations for atmospheric CH4 sink in tropical and subtropical regions.

  11. Variable conductivity and embolism in roots and branches of four contrasting tree species and their impacts on whole-plant hydraulic performance under future atmospheric CO{sub 2} concentration

    Energy Technology Data Exchange (ETDEWEB)

    Domec, J.C. [Duke Univ., Durham, NC (United States). Nicholas School of the Environment and Earth Sciences; North Carolina State Univ., Raleigh, NC (United States). Dept. of Forestry and Environmental Resources; Schafer, K. [Rutgers Univ., Newark, NJ (United States). Federated Dept. of Biological Sciences; Oren, R.; Kim, H.S. [Duke Univ., Durham, NC (United States). Nicholas School of the Environment and Earth Sciences; McCarthy, H.R. [California Univ., Irvine, CA (United States). Dept. of Earth Sciences

    2010-08-15

    Tree growth and wood quality are being affected by changes in atmospheric carbon dioxide (CO{sub 2}) concentrations and precipitation regimes. Plant photosynthesis is likely to be higher under elevated atmospheric CO{sub 2} concentrations, thereby increasing the availability of carbohydrates for growth. This study quantified the effect of elevated CO{sub 2} concentration on anatomical and functional traits related to water transport, gas exchange, water economy and drought tolerance. The conditions under which embolism in the xylem of roots and branches are most likely to occur were investigated on 4 tree species at the Duke Forest free-air CO{sub 2} enrichment (FACE) facility. The trees occupied different canopy strata and represented different xylem types. The study determined whether different xylem anatomies result in a wide range of hydraulic conductance and difference in resistance to cavitation. The link between liquid and gas-phase transport and how it is affected by elevated CO{sub 2} was then quantified. Physiological changes observed under elevated CO{sub 2} were not clearly related to structural change in the xylem of any of the species. The study showed that in some species, elevated CO{sub 2} changed the hydraulic pathways, most likely structurally, thereby affecting the liquid phase transport and reducing stomatal conductance. The results provided a better understanding of the physiological and anatomical mechanisms that determine the responses of tree species to drought, and more generally to global change. 96 refs., 3 tabs., 8 figs.

  12. The ratio of K to Ca in thalli of several species of lichens occurring on various trees

    Directory of Open Access Journals (Sweden)

    Stanisława Kuziel

    2015-05-01

    Full Text Available The per cent contents of K and Ca in 7 species of lichens and in the bark: of trees and extracts from this bark were determined. The ratio K : Ca was calculated. In the particular species of lichens collected from the tree the K : Ca ratio varies from 0.05 to 4.93. In the thalli of one species collected from various species of trees the content of cations varies, but the K: Ca ratio is more or less constant in particular species.

  13. 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. PMID:21302839

  14. Impacts of the Brown Tree Snake: Patterns of Decline and Species Persistence in Guam's Avifauna

    Science.gov (United States)

    Wiles, G.J.; Bart, J.; Beck, R.E., Jr.; Aguon, C.F.

    2003-01-01

    Predation by brown tree snakes (Boiga irregularis) devastated the avifauna of Guam in the Mariana Islands during the last half of the twentieth century, causing the extirpation or serious reduction of most of the island's 25 resident bird species. Past studies have provided qualitative descriptions of the decline of native forest birds but have not considered all species or presented quantitative analyses. We analyzed two sets of survey data gathered in northern Guam between 1976 and 1998 and reviewed unpublished sources to provide a comprehensive account of the impact of brown tree snakes on the island's birds. Our results indicate that 22 species, including 17 of 18 native species, were severely affected by snakes. Twelve species were likely extirpated as breeding residents on the main island, 8 others experienced declines of ???90% throughout the island or at least in the north, and 2 were kept at reduced population levels during all or much of the study. Declines of ???90% occurred rapidly, averaging just 8.9 years along three roadside survey routes combined and 1.6 years at a 100-ha forested study site. Declines in northern Guam were also relatively synchronous and occurred from about 1976 to 1986 for most species. The most important factor predisposing a species to coexistence with brown tree snakes was its ability to nest and roost at locations where snakes were uncommon. Large clutch size and large body size were also related to longer persistence times, although large body size appeared to delay, but not prevent, extirpation. Our results draw attention to the enormous detrimental impact that brown tree snakes are likely to have upon invading new areas. Increased containment efforts on Guam are needed to prevent further colonizations, but a variety of additional management efforts would also benefit the island's remaining bird populations.

  15. Allometric models for aboveground biomass of ten tree species in northeast China

    Directory of Open Access Journals (Sweden)

    Shuo Cai

    2013-07-01

    Full Text Available China contains 119 million hectares of natural forest, much of which is secondary forest. An accurate estimation of the biomass of these forests is imperative because many studies conducted in northeast China have only used primary forest and this may have resulted in biased estimates. This study analyzed secondary forest in the area using information from a forest inventory to develop allometric models of the aboveground biomass (AGB. The parameter values of the diameter at breast height (DBH, tree height (H, and crown length (CL were derived from a forest inventory of 2,733 trees in a 3.5 ha plot. The wood-specific gravity (WSG was determined for 109 trees belonging to ten species. A partial sampling method was also used to determine the biomass of branches (including stem, bark and foliage in 120 trees, which substantially easy the field works. The mean AGB was 110,729 kg ha–1. We developed four allometric models from the investigation and evaluated the utility of other 19 published ones for AGB in the ten tree species. Incorporation of full range of variables with WSG-DBH-H-CL, significantly improved the precision of the models. Some of models were chosen that best fitted each tree species with high precision (R2 = 0.939, SEE 0.167. At the latitude level, the estimated AGBof secondary forest was lower than that in mature primary forests, but higher than that in primary broadleaf forest and the average level in other types of forest likewise. 

  16. Allometric models for aboveground biomass of ten tree species in northeast China

    Directory of Open Access Journals (Sweden)

    Shuo Cai

    2013-05-01

    Full Text Available China contains 119 million hectares of natural forest, much of whichis secondary forest. An accurate estimation of the biomass of these forests is imperative because many studies conducted in northeast China have only used primary forest and this may have resulted in biased estimates. This study analyzed secondary forest in the area using information from a forest inventory to develop allometric models of the aboveground biomass (AGB. The parameter values of the diameter at breast height (DBH, tree height (H, and crown length (CL were derived from a forest inventory of 2,733 trees in a 3.5 ha plot. The wood-specific gravity (WSG was determined for 109 trees belonging to ten species. A partial sampling method was also used to determine the biomass of branches (including stem, bark and foliage in 120 trees, which substantially ease the field works. The mean AGB was110,729 kg ha–1. We developed four allometric models from the investigation and evaluated the utility of other 19 published ones for AGB in the ten tree species. Incorporation of full range of variables with WSG-DBH-H-CL, significantly improved the precision of the models. Some of models were chosen that best fitted each tree species with high precision (R2 ≥ 0.939, SEE 0.167. At the latitude level, the estimated AGB of secondary forest was lower than that in mature primary forests, but higher than that in primary broadleaf forest and the average level in other types of forest likewise.

  17. Hydraulic redistribution study in two native tree species of agroforestry parklands of West African dry savanna

    Science.gov (United States)

    Bayala, Jules; Heng, Lee Kheng; van Noordwijk, Meine; Ouedraogo, Sibiri Jean

    2008-11-01

    Hydraulic redistribution (HR) in karité ( Vitellaria paradoxa) and néré ( Parkia biglobosa) tree species was studied by monitoring the soil water potential ( ψs) using thermocouple psychrometers at four compass directions, various distances from trees and at different soil depths (max depth 80 cm) during the dry seasons of 2004 and 2005. A modified WaNuLCAS model was then used to infer the amount of water redistribued based on ψs values. Tree transpiration rate was also estimated from sap velocity using thermal dissipative probes (TDP) and sapwood area, and the contribution of hydraulically redistributed water in tree transpiration was determined. The results revealed on average that 46% of the psychrometer readings under karité and 33% under néré showed the occurrence of HR for the two years. Soil under néré displayed significantly lower fluctuations of ψs (0.16 MPa) compared to soil under karité (0.21 MPa). The results of this study indicated that the existence of HR leads to a higher ψs in the plant rhizosphere and hence is important for soil water dynamics and plant nutrition by making more accessible the soluble elements. The simulation showed that the amount of water redistributed would be approximately 73.0 L and 247.1 L per tree per day in 2005 for karité and néré, and would represent respectively 60% and 53% of the amount transpired a day. Even though the model has certainly overestimated the volume of water hydraulically redistributed by the two species, this water may play a key role in maintaining fine root viability and ensuring the well adaptation of these species to the dry areas. Therefore, knowledge of the extent of such transfers and of the seasonal patterns is required and is of paramount importance in parkland systems both for trees and associated crops.

  18. Drought stress limits the geographic ranges of two tree species via different physiological mechanisms.

    Science.gov (United States)

    Anderegg, Leander D L; HilleRisLambers, Janneke

    2016-03-01

    Range shifts are among the most ubiquitous ecological responses to anthropogenic climate change and have large consequences for ecosystems. Unfortunately, the ecophysiological forces that constrain range boundaries are poorly understood, making it difficult to mechanistically project range shifts. To explore the physiological mechanisms by which drought stress controls dry range boundaries in trees, we quantified elevational variation in drought tolerance and in drought avoidance-related functional traits of a widespread gymnosperm (ponderosa pine - Pinus ponderosa) and angiosperm (trembling aspen - Populus tremuloides) tree species in the southwestern USA. Specifically, we quantified tree-to-tree variation in growth, water stress (predawn and midday xylem tension), drought avoidance traits (branch conductivity, leaf/needle size, tree height, leaf area-to-sapwood area ratio), and drought tolerance traits (xylem resistance to embolism, hydraulic safety margin, wood density) at the range margins and range center of each species. Although water stress increased and growth declined strongly at lower range margins of both species, ponderosa pine and aspen showed contrasting patterns of clinal trait variation. Trembling aspen increased its drought tolerance at its dry range edge by growing stronger but more carbon dense branch and leaf tissues, implying an increased cost of growth at its range boundary. By contrast, ponderosa pine showed little elevational variation in drought-related traits but avoided drought stress at low elevations by limiting transpiration through stomatal closure, such that its dry range boundary is associated with limited carbon assimilation even in average climatic conditions. Thus, the same climatic factor (drought) may drive range boundaries through different physiological mechanisms - a result that has important implications for process-based modeling approaches to tree biogeography. Further, we show that comparing intraspecific patterns of

  19. The effect of organic acids on base cation leaching from the forest floor under six North American tree species

    NARCIS (Netherlands)

    Dijkstra, F.A.; Geibe, C.; Holmstrom, S.; Lundstrom, U.S.; Breemen, van N.

    2001-01-01

    Organic acidity and its degree of neutralization in the forest floor can have large consequences for base cation leaching under different tree species. We investigated the effect of organic acids on base cation leaching from the forest floor under six common North American tree species. Forest floor

  20. Status of chemical elements in Atlantic Forest tree species near an industrial complex

    International Nuclear Information System (INIS)

    Environmental quality assessment studies have been conducted with tree species largely distributed in the Atlantic Forest. Leaf and soil samples were collected in the conservation unit Parque Estadual da Serra do Mar (PESM) nearby the industrial complex of Cubatao, Sao Paulo State, Brazil, and analyzed for chemical elements by instrumental neutron activation analysis. Results were compared to background values obtained in the Parque Estadual Carlos Botelho (PECB). The higher As, Fe, Hg and Zn mass fractions in the tree leaves of PESM indicated anthropogenic influence on this conservation unit. (author)

  1. Different tree species affect soil respiration spatial distribution in a subtropical forest of southern Taiwan

    Science.gov (United States)

    Chiang, Po-Neng; Yu, Jui-Chu; Wang, Ya-nan; Lai, Yen-Jen

    2014-05-01

    Global forests contain 69% of total carbon stored in forest soil and litter. But the carbon storage ability and release rate of warming gases of forest soil also affect global climate change. Soil carbon cycling processes are paid much attention by ecological scientists and policy makers because of the possibility of carbon being stored in soil via land use management. Soil respiration contributed large part of terrestrial carbon flux, but the relationship of soil respiration and climate change was still obscurity. Most of soil respiration researches focus on template and tropical area, little was known that in subtropical area. Afforestation is one of solutions to mitigate CO2 increase and to sequestrate CO2 in tree and soil. Therefore, the objective of this study is to clarify the relationship of tree species and soil respiration distribution in subtropical broad-leaves plantation in southern Taiwan. The research site located on southern Taiwan was sugarcane farm before 2002. The sugarcane was removed and fourteen broadleaved tree species were planted in 2002-2005. Sixteen plots (250m*250m) were set on 1 km2 area, each plot contained 4 subplots (170m2). The forest biomass (i.e. tree height, DBH) understory biomass, litter, and soil C were measured and analyzed at 2011 to 2012. Soil respiration measurement was sampled in each subplot in each month. The soil belongs to Entisol with over 60% of sandstone. The soil pH is 5.5 with low base cations because of high sand percentage. Soil carbon storage showed significantly negative relationship with soil bulk density (p<0.001) in research site. The differences of distribution of live tree C pool among 16 plots were affected by growth characteristic of tree species. Data showed that the accumulation amount of litterfall was highest in December to February and lowest in June. Different tree species planted in 16 plots, resulting in high spatial variation of litterfall amount. It also affected total amount of litterfall

  2. SimPhy: Phylogenomic Simulation of Gene, Locus, and Species Trees

    Science.gov (United States)

    Mallo, Diego; De Oliveira Martins, Leonardo; Posada, David

    2016-01-01

    We present a fast and flexible software package—SimPhy—for the simulation of multiple gene families evolving under incomplete lineage sorting, gene duplication and loss, horizontal gene transfer—all three potentially leading to species tree/gene tree discordance—and gene conversion. SimPhy implements a hierarchical phylogenetic model in which the evolution of species, locus, and gene trees is governed by global and local parameters (e.g., genome-wide, species-specific, locus-specific), that can be fixed or be sampled from a priori statistical distributions. SimPhy also incorporates comprehensive models of substitution rate variation among lineages (uncorrelated relaxed clocks) and the capability of simulating partitioned nucleotide, codon, and protein multilocus sequence alignments under a plethora of substitution models using the program INDELible. We validate SimPhy's output using theoretical expectations and other programs, and show that it scales extremely well with complex models and/or large trees, being an order of magnitude faster than the most similar program (DLCoal-Sim). In addition, we demonstrate how SimPhy can be useful to understand interactions among different evolutionary processes, conducting a simulation study to characterize the systematic overestimation of the duplication time when using standard reconciliation methods. SimPhy is available at https://github.com/adamallo/SimPhy, where users can find the source code, precompiled executables, a detailed manual and example cases. PMID:26526427

  3. Mechanism Underlying the Spatial Pattern Formation of Dominant Tree Species in a Natural Secondary Forest.

    Directory of Open Access Journals (Sweden)

    Guodong Jia

    Full Text Available Studying the spatial pattern of plant species may provide significant insights into processes and mechanisms that maintain stand stability. To better understand the dynamics of naturally regenerated secondary forests, univariate and bivariate Ripley's L(r functions were employed to evaluate intra-/interspecific relationships of four dominant tree species (Populus davidiana, Betula platyphylla, Larix gmelinii and Acer mono and to distinguish the underlying mechanism of spatial distribution. The results showed that the distribution of soil, water and nutrients was not fragmented but presented clear gradients. An overall aggregated distribution existed at most distances. No correlation was found between the spatial pattern of soil conditions and that of trees. Both positive and negative intra- and interspecific relationships were found between different DBH classes at various distances. Large trees did not show systematic inhibition of the saplings. By contrast, the inhibition intensified as the height differences increased between the compared pairs. Except for Larix, universal inhibition of saplings by upper layer trees occurred among other species, and this reflected the vertical competition for light. Therefore, we believe that competition for light rather than soil nutrients underlies the mechanism driving the formation of stand spatial pattern in the rocky mountainous areas examined.

  4. Mechanism Underlying the Spatial Pattern Formation of Dominant Tree Species in a Natural Secondary Forest.

    Science.gov (United States)

    Jia, Guodong; Yu, Xinxiao; Fan, Dengxing; Jia, Jianbo

    2016-01-01

    Studying the spatial pattern of plant species may provide significant insights into processes and mechanisms that maintain stand stability. To better understand the dynamics of naturally regenerated secondary forests, univariate and bivariate Ripley's L(r) functions were employed to evaluate intra-/interspecific relationships of four dominant tree species (Populus davidiana, Betula platyphylla, Larix gmelinii and Acer mono) and to distinguish the underlying mechanism of spatial distribution. The results showed that the distribution of soil, water and nutrients was not fragmented but presented clear gradients. An overall aggregated distribution existed at most distances. No correlation was found between the spatial pattern of soil conditions and that of trees. Both positive and negative intra- and interspecific relationships were found between different DBH classes at various distances. Large trees did not show systematic inhibition of the saplings. By contrast, the inhibition intensified as the height differences increased between the compared pairs. Except for Larix, universal inhibition of saplings by upper layer trees occurred among other species, and this reflected the vertical competition for light. Therefore, we believe that competition for light rather than soil nutrients underlies the mechanism driving the formation of stand spatial pattern in the rocky mountainous areas examined. PMID:27028757

  5. Drivers of Tree Growth, Mortality and Harvest Preferences in Species-Rich Plantations for Smallholders and Communities in the Tropics

    Science.gov (United States)

    Nguyen, Huong; Vanclay, Jerome; Herbohn, John; Firn, Jennifer

    2016-01-01

    There is growing interest in multi-species tropical plantations but little information exists to guide their design and silviculture. The Rainforestation Farming system is the oldest tropical polyculture planting system in the Philippines and provides a unique opportunity to understand the underlying processes affecting tree performance within diverse plantings. Data collected from 85 plots distributed across the 18 mixed-species plantations in the Philippines was used to identify the factors influencing growth, probability of harvest, and death of trees in these complex plantings. The 18 sites (aged from 6 to 11 years at time of first measurement) were measured on three occasions over a 6-year period. We used data from the first period of data collection to develop models predicting harvesting probability and growth of trees in the second period. We found little evidence that tree species diversity had an effect on tree growth and tree loss at the community level, although a negative effect was found on tree growth of specific species such as Parashorea plicata and Swietenia macrophylla. While tree density of stands at age 10+ years (more than 1000 trees/ha with diameter > 5cm) did not have an impact on growth, growth rates were decreasing in stands with a high basal area. Tree size in the first period of measure was a good predictor for both tree growth and tree status in the next period, with larger trees tending to grow faster and having a greater chance of being harvested, and a lower possibility of mortality than smaller trees. Shade-intolerant trees were both more likely to be harvested, and had a higher probability of death, than shade-tolerant individuals. Native species and exotic species were equally likely to have been lost from the plots between measurement periods. However, shade-tolerant native trees were likely to grow faster than the others at age 10+ years. Our findings suggest that species traits (e.g. shade tolerance) could play an important

  6. Estimating the global conservation status of more than 15,000 Amazonian tree species

    Science.gov (United States)

    ter Steege, Hans; Pitman, Nigel C. A.; Killeen, Timothy J.; Laurance, William F.; Peres, Carlos A.; Guevara, Juan Ernesto; Salomão, Rafael P.; Castilho, Carolina V.; Amaral, Iêda Leão; de Almeida Matos, Francisca Dionízia; de Souza Coelho, Luiz; Magnusson, William E.; Phillips, Oliver L.; de Andrade Lima Filho, Diogenes; de Jesus Veiga Carim, Marcelo; Irume, Mariana Victória; Martins, Maria Pires; Molino, Jean-François; Sabatier, Daniel; Wittmann, Florian; López, Dairon Cárdenas; da Silva Guimarães, José Renan; Mendoza, Abel Monteagudo; Vargas, Percy Núñez; Manzatto, Angelo Gilberto; Reis, Neidiane Farias Costa; Terborgh, John; Casula, Katia Regina; Montero, Juan Carlos; Feldpausch, Ted R.; Honorio Coronado, Euridice N.; Montoya, Alvaro Javier Duque; Zartman, Charles Eugene; Mostacedo, Bonifacio; Vasquez, Rodolfo; Assis, Rafael L.; Medeiros, Marcelo Brilhante; Simon, Marcelo Fragomeni; Andrade, Ana; Camargo, José Luís; Laurance, Susan G. W.; Nascimento, Henrique Eduardo Mendonça; Marimon, Beatriz S.; Marimon, Ben-Hur; Costa, Flávia; Targhetta, Natalia; Vieira, Ima Célia Guimarães; Brienen, Roel; Castellanos, Hernán; Duivenvoorden, Joost F.; Mogollón, Hugo F.; Piedade, Maria Teresa Fernandez; Aymard C., Gerardo A.; Comiskey, James A.; Damasco, Gabriel; Dávila, Nállarett; García-Villacorta, Roosevelt; Diaz, Pablo Roberto Stevenson; Vincentini, Alberto; Emilio, Thaise; Levis, Carolina; Schietti, Juliana; Souza, Priscila; Alonso, Alfonso; Dallmeier, Francisco; Ferreira, Leandro Valle; Neill, David; Araujo-Murakami, Alejandro; Arroyo, Luzmila; Carvalho, Fernanda Antunes; Souza, Fernanda Coelho; do Amaral, Dário Dantas; Gribel, Rogerio; Luize, Bruno Garcia; Pansonato, Marcelo Petrati; Venticinque, Eduardo; Fine, Paul; Toledo, Marisol; Baraloto, Chris; Cerón, Carlos; Engel, Julien; Henkel, Terry W.; Jimenez, Eliana M.; Maas, Paul; Mora, Maria Cristina Peñuela; Petronelli, Pascal; Revilla, Juan David Cardenas; Silveira, Marcos; Stropp, Juliana; Thomas-Caesar, Raquel; Baker, Tim R.; Daly, Doug; Paredes, Marcos Ríos; da Silva, Naara Ferreira; Fuentes, Alfredo; Jørgensen, Peter Møller; Schöngart, Jochen; Silman, Miles R.; Arboleda, Nicolás Castaño; Cintra, Bruno Barçante Ladvocat; Valverde, Fernando Cornejo; Di Fiore, Anthony; Phillips, Juan Fernando; van Andel, Tinde R.; von Hildebrand, Patricio; Barbosa, Edelcilio Marques; de Matos Bonates, Luiz Carlos; de Castro, Deborah; de Sousa Farias, Emanuelle; Gonzales, Therany; Guillaumet, Jean-Louis; Hoffman, Bruce; Malhi, Yadvinder; de Andrade Miranda, Ires Paula; Prieto, Adriana; Rudas, Agustín; Ruschell, Ademir R.; Silva, Natalino; Vela, César I. A.; Vos, Vincent A.; Zent, Eglée L.; Zent, Stanford; Cano, Angela; Nascimento, Marcelo Trindade; Oliveira, Alexandre A.; Ramirez-Angulo, Hirma; Ramos, José Ferreira; Sierra, Rodrigo; Tirado, Milton; Medina, Maria Natalia Umaña;