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Sample records for deciduous tree leaves

  1. Ecophysiological and seasonal variations in Cd, Pb, Zn, and Ni concentrations in the leaves of urban deciduous trees in Istanbul

    International Nuclear Information System (INIS)

    Baycu, Guelriz; Tolunay, Doganay; Ozden, Hakan; Guenebakan, Suereyya

    2006-01-01

    The concentrations of Cd, Pb, Zn and Ni were measured in the leaves of 7 species of deciduous trees, from the urban sites of Istanbul, in both the Spring and Autumn seasons. We detected some differences in the heavy metal concentrations of the control and urban site samples of identical species. Highest concentrations of Cd were detected in Populus, Pb in Aesculus and Robinia, Zn in Populus, and Ni in Robinia and Fraxinus. Lowest chlorophyll content and highest peroxidase (POD) activity was found in the urban site samples of Acer. We have found a positive correlation between the increase in the POD activity and the Pb concentration in Populus. Generally, the tree species investigated in this study, are considered to have different tolerance levels to heavy metal pollution. The data obtained show that the chlorophyll content and the POD activity may be used as heavy metal stress biomarkers in the urban trees. - Ecophysiological changes in the urban trees may be used as heavy metal stress biomarkers

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

    Science.gov (United States)

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

    2012-06-01

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

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

    Science.gov (United States)

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

    2014-02-01

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

  4. Compartment model for long-term contamination prediction in deciduous fruit trees after a nuclear accident

    International Nuclear Information System (INIS)

    Antonopoulos-Domis, M.; Clouvas, A.; Gagianas, A.

    1990-01-01

    Radiocesium contamination from the Chernobyl accident of different parts (fruits, leaves, and shoots) of selected apricot trees in North Greece was systematically measured in 1987 and 1988. The results are presented and discussed in the framework of a simple compartment model describing the long-term contamination uptake mechanism of deciduous fruit trees after a nuclear accident

  5. Simulating carbon dioxide exchange rates of deciduous tree species: evidence for a general pattern in biochemical changes and water stress response.

    Science.gov (United States)

    Reynolds, Robert F; Bauerle, William L; Wang, Ying

    2009-09-01

    Deciduous trees have a seasonal carbon dioxide exchange pattern that is attributed to changes in leaf biochemical properties. However, it is not known if the pattern in leaf biochemical properties - maximum Rubisco carboxylation (V(cmax)) and electron transport (J(max)) - differ between species. This study explored whether a general pattern of changes in V(cmax), J(max), and a standardized soil moisture response accounted for carbon dioxide exchange of deciduous trees throughout the growing season. The model MAESTRA was used to examine V(cmax) and J(max) of leaves of five deciduous trees, Acer rubrum 'Summer Red', Betula nigra, Quercus nuttallii, Quercus phellos and Paulownia elongata, and their response to soil moisture. MAESTRA was parameterized using data from in situ measurements on organs. Linking the changes in biochemical properties of leaves to the whole tree, MAESTRA integrated the general pattern in V(cmax) and J(max) from gas exchange parameters of leaves with a standardized soil moisture response to describe carbon dioxide exchange throughout the growing season. The model estimates were tested against measurements made on the five species under both irrigated and water-stressed conditions. Measurements and modelling demonstrate that the seasonal pattern of biochemical activity in leaves and soil moisture response can be parameterized with straightforward general relationships. Over the course of the season, differences in carbon exchange between measured and modelled values were within 6-12 % under well-watered conditions and 2-25 % under water stress conditions. Hence, a generalized seasonal pattern in the leaf-level physiological change of V(cmax) and J(max), and a standardized response to soil moisture was sufficient to parameterize carbon dioxide exchange for large-scale evaluations. Simplification in parameterization of the seasonal pattern of leaf biochemical activity and soil moisture response of deciduous forest species is demonstrated. This

  6. Lead and cadmium in leaves of deciduous trees in Beijing, China: Development of a metal accumulation index (MAI)

    International Nuclear Information System (INIS)

    Liu Yanju; Zhu Yongguan; Ding Hui

    2007-01-01

    Lead and cadmium uptake was investigated for common deciduous street trees in Beijing in this study. Species having Cd accumulation included Populus tomentosa, Sophora japonica and Catalpa speciosa. P. tomentosa had the highest ratios between leaf and soil Cd (0.848), followed by S. japonica (0.536), C. speciosa (0.493), Paulownia tomentosa (0.453) and Juglans regia (0.415). Pb levels were high in leaves of C. speciosa, J. regia and Pa. tomentosa. S. japonica had the highest ratio between leaf Pb and soil Pb (0.146), followed by Pa. tomentosa (0.143), Ginko biloba (0.103) and C. speciosa (0.095). A predictive foliar metal accumulation index (MAI) was developed and C. speciosa was calculated to have the highest MAI value (53.8). This suggests that C. speciosa would be a good choice for planting in areas of Beijing where soil contamination with Cd and Pb may be a problem. - Catalpa speciosa had the highest MAI value

  7. Vertical and horizontal distribution of radiocesium around trees in forest soil of deciduous forests, Fukushima, Japan

    Energy Technology Data Exchange (ETDEWEB)

    Takada, Mono; Oba, Yurika; Nursal, Wim I.; Yamada, Toshihiro; Okuda, Toshinori [Graduate School of Integrated Arts and Sciences, Hiroshima University, 1-7-1 Kagamiyama, Higashi- Hiroshima 739-8521 (Japan); Shizuma, Kiyoshi [Graduate School of Engineering, Hiroshima University, 1-4-1 Kagamiyama, Higashi-Hiroshima 739-8527 (Japan)

    2014-07-01

    After the 2011 Nuclear Power Plant accident in Japan, large amount of radionuclides were deposited and remains in the forest land of Fukushima region, yet still uncertain how much deposition stays in the forest. This region is mostly covered by the secondary deciduous forest which sporadically includes Japanese fir (Abies firma). As the leaves of all deciduous trees were shed, we hypothesized that the amounts of deposition radionuclides will be exhibit difference between the conifer trees (Japanese fir) and the other deciduous trees. As these trees inhabit on steep slopes, we also hypothesized there are differences in the radionuclides deposition in soils in relation to the position around tree trunk base (upper side, lower side and mid side at the foot of trees), tree species and slope angles. Study site and method: our study was conducted in deciduous forest of Fukushima region in August 2013, two and a half years after the accident. Samples of litter layer and two soil layers (0 - 5, 5 - 10 cm) were collected under Abies firma and eight deciduous tree species. In total 23 trees in eight forest stands were investigated. Under one tree, samples were taken from four pints (upper side, lower side and mid sides at the foot of trees) around a tree trunk within a radius of one meter from the base of tree trunks. Angle of slope at each tree was also checked. The samples were dried (70 deg. C, 48 hr) and radiocesium and potassium-40 was determined by a germanium detector (GEM Series HPGe Coaxial Detector System) (measurement time 300 - 30000 sec). Results and discussion: we found that radiocesium contained in litter layer accounts for more than 80% of total amount (within litter layer to 10 cm depth from the surface), and almost all the radiocesium exists within litter layer up to 5 cm depth. Although it is well known that cesium shows similar movement to potassium in a plant body, soil contained much more amount of potassium-40 than litter layer. We predicted that

  8. Distribution and trends of mercury in deciduous tree cores

    International Nuclear Information System (INIS)

    Siwik, Eden I.H.; Campbell, Linda M.; Mierle, Gregory

    2010-01-01

    The distribution of total mercury (THg) within common deciduous trees and the applicability of tree cores as biomonitors of historical environmental THg trends were assessed for both contaminated and reference sites around Kingston, Ontario. Samples were collected from Acer spp., Quercus spp. Populus spp. and Salix spp. Bark and wood THg concentrations were found to be highly correlated whereas soil and wood THg concentrations were not. There were no temporal relationships for THg in dated tree rings corresponding with any other known environmental Hg trends. The shoreline speciess, Populus and Salix spp., had the greatest bark and wood Hg concentrations reaching 18 ng/g, significantly higher than for inland trees Quercus and Acer spp. with maximum values of 7 and 1.2 ng/g for bark and wood respectively. While tree cores cannot be reliably used as temporal THg biomonitors, there is promise for tree species such as Populus spp and Salix spp as spatial indicators of local long-term Hg contamination. - Total mercury trends in several deciduous trees did not follow expected environmental trends. Shoreline species (willow and popular) had higher wood THg than inland species (oak and maple).

  9. Deciduous trees are a large and overlooked sink for snowmelt water in the boreal forest

    Science.gov (United States)

    Young, Jessica; Bolton, W. Robert; Bhatt, Uma; Cristobal, Jordi; Thoman, Richard

    2016-01-01

    The terrestrial water cycle contains large uncertainties that impact our understanding of water budgets and climate dynamics. Water storage is a key uncertainty in the boreal water budget, with tree water storage often ignored. The goal of this study is to quantify tree water content during the snowmelt and growing season periods for Alaskan and western Canadian boreal forests. Deciduous trees reached saturation between snowmelt and leaf-out, taking up 21–25% of the available snowmelt water, while coniferous trees removed <1%. We found that deciduous trees removed 17.8–20.9 billion m3 of snowmelt water, which is equivalent to 8.7–10.2% of the Yukon River’s annual discharge. Deciduous trees transpired 2–12% (0.4–2.2 billion m3) of the absorbed snowmelt water immediately after leaf-out, increasing favorable conditions for atmospheric convection, and an additional 10–30% (2.0–5.2 billion m3) between leaf-out and mid-summer. By 2100, boreal deciduous tree area is expected to increase by 1–15%, potentially resulting in an additional 0.3–3 billion m3 of snowmelt water removed from the soil per year. This study is the first to show that deciduous tree water uptake of snowmelt water represents a large but overlooked aspect of the water balance in boreal watersheds.

  10. The interaction between freezing tolerance and phenology in temperate deciduous trees

    Directory of Open Access Journals (Sweden)

    Yann eVitasse

    2014-10-01

    Full Text Available Temperate climates are defined by a distinct temperature seasonality with large and often unpredictable weather during any of the four seasons. To thrive in such climates, trees have to withstand a cold winter and the stochastic occurrence of freeze events during any time of the year. The physiological mechanisms trees adopt to escape, avoid and tolerate freezing temperatures include a cold acclimation in autumn, a dormancy period during winter (leafless in deciduous trees, and the maintenance of a certain freezing tolerance during dehardening in early spring. The change from one phase to the next is mediated by complex interactions between temperature and photoperiod. This review aims at providing an overview of the interplay between phenology of leaves and species-specific freezing resistance. First, we address the long-term evolutionary responses that enabled temperate trees to tolerate certain low temperature extremes. We provide evidence that short term acclimation of freezing resistance plays a crucial role both in dormant and active buds, including re-acclimation to cold conditions following warm spells. This ability declines to almost zero during leaf emergence. Second, we show that the risk that native temperate trees encounter freeze injuries is low and is confined to spring and underline that this risk might be altered by climate warming depending on species-specific phenological responses to environmental cues.

  11. [NDVI difference rate recognition model of deciduous broad-leaved forest based on HJ-CCD remote sensing data].

    Science.gov (United States)

    Wang, Yan; Tian, Qing-Jiu; Huang, Yan; Wei, Hong-Wei

    2013-04-01

    The present paper takes Chuzhou in Anhui Province as the research area, and deciduous broad-leaved forest as the research object. Then it constructs the recognition model about deciduous broad-leaved forest was constructed using NDVI difference rate between leaf expansion and flowering and fruit-bearing, and the model was applied to HJ-CCD remote sensing image on April 1, 2012 and May 4, 2012. At last, the spatial distribution map of deciduous broad-leaved forest was extracted effectively, and the results of extraction were verified and evaluated. The result shows the validity of NDVI difference rate extraction method proposed in this paper and also verifies the applicability of using HJ-CCD data for vegetation classification and recognition.

  12. Flowering Trees

    Indian Academy of Sciences (India)

    Flowering Trees. Gyrocarpus americanus Jacq. (Helicopter Tree) of Hernandiaceae is a moderate size deciduous tree that grows to about 12 m in height with a smooth, shining, greenish-white bark. The leaves are ovate, rarely irregularly ... flowers which are unpleasant smelling. Fruit is a woody nut with two long thin wings.

  13. Evolutionarily stable strategy of carbon and nitrogen investments in forest leaves and its application in vegetation dynamic modeling

    Science.gov (United States)

    Weng, E.; Farrior, C.; Dybzinski, R.; Pacala, S. W.

    2015-12-01

    Leaf mass per area (LMA) and leaf lifespan (LL) are two highly correlated plant traits that are key to plant physiological and ecological properties. Usually, low LMA means short LL, high nitrogen (N) content per unit mass, and fast turnover rates of nutrients; high LMA leads to long LL, low N content, and slow turnover rates. Deciduous trees with low LMA and short lifespan leaves have low carbon cost but high nitrogen demand; and evergreen trees, with high LMA and long lifespan leaves, have high carbon cost but low nitrogen demand. These relationships lead to: 1) evergreen trees have higher leaf area index than deciduous trees; 2) evergreen trees' carbon use efficiency is lower than the deciduous trees' because of their thick leaves and therefore high maintenance respiration; 3) the advantage of evergreens trees brought by their extra leaves over deciduous trees diminishes with increase N in ecosystem. These facts determine who will win when trees compete with each other in a N-limited ecosystem. In this study, we formulate a mathematical model according to the relationships between LMA, LL, leaf nitrogen, and leaf building and maintenance cost, where LMA is the fundamental variable determining the other three. We analyze the evolutionarily stable strategies (ESSs) of LMA with this mathematical model by examining the benefits of carbon and nitrogen investments to leaves in ecosystems with different N. The model shows the ESS converges to low LMA at high N and high LMA at low N. At intermediate N, there are two ESSs at low and high ends of LMA, respectively. The ESS also leads to low forest productivity by outcompeting the possible high productive strategies. We design a simulation scheme in an individual-based competition model (LM3-PPA) to simulate forest dynamics as results of the competition between deciduous and evergreen trees in three different biomes, which are temperate deciduous forest, deciduous-evergreen mixed forest, and boreal evergreen forest. The

  14. The longevity of broadleaf deciduous trees in Northern Hemisphere temperate forests: insights from tree-ring series

    Directory of Open Access Journals (Sweden)

    Alfredo eDi Filippo

    2015-05-01

    Full Text Available Understanding the factors controlling the expression of longevity in trees is still an outstanding challenge for tree biologists and forest ecologists. We gathered tree-ring data and literature for broadleaf deciduous (BD temperate trees growing in closed-canopy old-growth forests in the Northern Hemisphere to explore the role of geographic patterns, climate variability, and growth rates on longevity. Our pan-continental analysis, covering 32 species from 12 genera, showed that 300-400 years can be considered a baseline threshold for maximum tree lifespan in many temperate deciduous forests. Maximum age varies greatly in relation to environmental features, even within the same species. Tree longevity is generally promoted by reduced growth rates across large genetic differences and environmental gradients. We argue that slower growth rates, and the associated smaller size, provide trees with an advantage against biotic and abiotic disturbance agents, supporting the idea that size, not age, is the main constraint to tree longevity. The oldest trees were living most of their life in subordinate canopy conditions and/or within primary forests in cool temperate environments and outside major storm tracks. Very old trees are thus characterized by slow growth and often live in forests with harsh site conditions and infrequent disturbance events that kill much of the trees. Temperature inversely controls the expression of longevity in mesophilous species (Fagus spp., but its role in Quercus spp. is more complex and warrants further research in disturbance ecology. Biological, ecological and historical drivers must be considered to understand the constraints imposed to longevity within different forest landscapes.

  15. Divergent Hydraulic Safety Strategies in Three Co-occurring Anacardiaceae Tree Species in a Chinese Savanna.

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    Zhang, Shu-Bin; Zhang, Jiao-Lin; Cao, Kun-Fang

    2016-01-01

    Vulnerability segmentation, the condition under which plant leaves are more vulnerable to drought-induced cavitation than stems, may act as a "safety valve" to protect stems from hydraulic failure. Evergreen, winter-deciduous, and drought-deciduous tree species co-occur in tropical savannas, but there have been no direct studies on the role of vulnerability segmentation and stomatal regulation in maintaining hydraulic safety in trees with these three leaf phenologies. To this end, we selected three Anacardiaceae tree species co-occurring in a Chinese savanna, evergreen Pistacia weinmanniifolia , drought-deciduous Terminthia paniculata , and winter-deciduous Lannea coromandelica , to study inter-species differentiation in leaf and stem hydraulic safety. We found that the two deciduous species had significantly higher sapwood-specific hydraulic conductivity and leaf-specific hydraulic conductance than the evergreen species. Moreover, two deciduous species were more vulnerable to stem cavitation than the evergreen species, although both drought-deciduous species and evergreen species had drought-resistance leaves. The evergreen species maintained a wide hydraulic safety margin (HSM) in stems and leaves; which was achieved by embolism resistance of both stems and leaves and isohydric stomatal control. Both deciduous species had limited HSMs in stems and leaves, being isohydric in the winter-deciduous species and anisohydric in drought-deciduous species. The difference in water potential at 50% loss of hydraulic conductivity between the leaves and the terminal stems (P50 leaf-stem ) was positive in P. weinmanniifolia and L. coromandelica , whereas, T. paniculata exhibited a lack of vulnerability segmentation. In addition, differences in hydraulic architecture were found to be closely related to other structural traits, i.e., leaf mass per area, wood density, and sapwood anatomy. Overall, the winter-deciduous species exhibits a drought-avoidance strategy that maintains

  16. Flowering Trees

    Indian Academy of Sciences (India)

    user

    Flowering Trees. Gliricidia sepium(Jacq.) Kunta ex Walp. (Quickstick) of Fabaceae is a small deciduous tree with. Pinnately compound leaves. Flower are prroduced in large number in early summer on terminal racemes. They are attractive, pinkish-white and typically like bean flowers. Fruit is a few-seeded flat pod.

  17. Plant Identification Characteristics for Deciduous Trees & Shrubs. Lesson Plans.

    Science.gov (United States)

    Burkholder, Kathy

    This manual contains a group of lesson plans designed for use with a slide series (not included here). Its purpose is to introduce students to the basic concepts and terminology used in the identification of deciduous trees and shrubs. The manual is composed of 12 lesson plans. The first lesson is an introduction to plant identification. The…

  18. Are leaves that fall from imidacloprid-treated maple trees to control Asian longhorned beetles toxic to non-target decomposer organisms?

    Science.gov (United States)

    Kreutzweiser, David P; Good, Kevin P; Chartrand, Derek T; Scarr, Taylor A; Thompson, Dean G

    2008-01-01

    The systemic insecticide imidacloprid may be applied to deciduous trees for control of the Asian longhorned beetle, an invasive wood-boring insect. Senescent leaves falling from systemically treated trees contain imidacloprid concentrations that could pose a risk to natural decomposer organisms. We examined the effects of foliar imidacloprid concentrations on decomposer organisms by adding leaves from imidacloprid-treated sugar maple trees to aquatic and terrestrial microcosms under controlled laboratory conditions. Imidacloprid in maple leaves at realistic field concentrations (3-11 mg kg(-1)) did not affect survival of aquatic leaf-shredding insects or litter-dwelling earthworms. However, adverse sublethal effects at these concentrations were detected. Feeding rates by aquatic insects and earthworms were reduced, leaf decomposition (mass loss) was decreased, measurable weight losses occurred among earthworms, and aquatic and terrestrial microbial decomposition activity was significantly inhibited. Results of this study suggest that sugar maple trees systemically treated with imidacloprid to control Asian longhorned beetles may yield senescent leaves with residue levels sufficient to reduce natural decomposition processes in aquatic and terrestrial environments through adverse effects on non-target decomposer organisms.

  19. Flowering Trees

    Indian Academy of Sciences (India)

    Flowering Trees. Acrocarpus fraxinifolius Wight & Arn. (PINK CEDAR, AUSTRALIAN ASH) of. Caesalpiniaceae is a lofty unarmed deciduous native tree that attains a height of 30–60m with buttresses. Bark is thin and light grey. Leaves are compound and bright red when young. Flowers in dense, erect, axillary racemes.

  20. Chronic water stress reduces tree growth and the carbon sink of deciduous hardwood forests.

    Science.gov (United States)

    Brzostek, Edward R; Dragoni, Danilo; Schmid, Hans Peter; Rahman, Abdullah F; Sims, Daniel; Wayson, Craig A; Johnson, Daniel J; Phillips, Richard P

    2014-08-01

    Predicted decreases in water availability across the temperate forest biome have the potential to offset gains in carbon (C) uptake from phenology trends, rising atmospheric CO2 , and nitrogen deposition. While it is well established that severe droughts reduce the C sink of forests by inducing tree mortality, the impacts of mild but chronic water stress on forest phenology and physiology are largely unknown. We quantified the C consequences of chronic water stress using a 13-year record of tree growth (n = 200 trees), soil moisture, and ecosystem C balance at the Morgan-Monroe State Forest (MMSF) in Indiana, and a regional 11-year record of tree growth (n > 300 000 trees) and water availability for the 20 most dominant deciduous broadleaf tree species across the eastern and midwestern USA. We show that despite ~26 more days of C assimilation by trees at the MMSF, increasing water stress decreased the number of days of wood production by ~42 days over the same period, reducing the annual accrual of C in woody biomass by 41%. Across the deciduous forest region, water stress induced similar declines in tree growth, particularly for water-demanding 'mesophytic' tree species. Given the current replacement of water-stress adapted 'xerophytic' tree species by mesophytic tree species, we estimate that chronic water stress has the potential to decrease the C sink of deciduous forests by up to 17% (0.04 Pg C yr(-1) ) in the coming decades. This reduction in the C sink due to mesophication and chronic water stress is equivalent to an additional 1-3 days of global C emissions from fossil fuel burning each year. Collectively, our results indicate that regional declines in water availability may offset the growth-enhancing effects of other global changes and reduce the extent to which forests ameliorate climate warming. © 2014 John Wiley & Sons Ltd.

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

    International Nuclear Information System (INIS)

    Calder, W.J.; Lifferth, G.; Clair, S.B.S.; Moritz, M.A.

    2010-01-01

    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 un investigated. 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.

  2. 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.

  3. Nitrogen storage and distribution and reuse of 15N-urea applied in autumn on different branch leaves of winter Jujube (Zizyphus jujuba Mill. var. inermis Rehd) trees

    International Nuclear Information System (INIS)

    Zhao Dengchao; Jiang Yuanmao; Peng Futian; Zhang Xu; Sui Jing; He Naibo

    2007-01-01

    The effectiveness of foliage spraying with urea to augment the seasonal internal cycling of N in winter Jujube was studied. Different branches leaves of 6-year-old trees were painted with 5% abundance of 15 N-urea solution after fruit harvesting. Results showed that 15 N was detected in all the tree organs during the dormant season. In the following year 15 N was also detected in new growth organs (deciduous spurs, leaves and flowers). The treated branches and adjacent organs were the main sinks of Nitrogen in the dormant season. Ndff% in the treated branches was significantly decreased during dormant season. And a decrease of 59.13% was observed in the new growth branch treated and 60.05% in the perennial branches. Reserved nitrogen was reused for initial growth (leaves and deciduous spurs). 15 N stored in perennial organs also remobilized to sustain new growth of treated branches. It is different from the treated new growth branch, 15 N stored in the treated perennial branches is not only transported for new organs growth, but also for roots growth. (authors)

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

    Science.gov (United States)

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

    2013-08-01

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

  5. Growth and defense in deciduous trees and shrubs under UV-B

    International Nuclear Information System (INIS)

    Julkunen-Tiitto, Riitta; Haeggman, Hely; Aphalo, Pedro J.; Lavola, Anu; Tegelberg, Riitta; Veteli, Timo

    2005-01-01

    Reflection by waxy or resinous surface structures and hairs, repair reactions of biomolecules and induction of different sheltering components provide the means of plant protection from harmful solar UV-B radiation. Secondary products, especially flavonoids and phenolic acids as defense components are also important in plant tolerance to UV-B, fulfilling the dual role as screens that reduce UV-B penetration in plant tissues, and as antioxidants protecting from damage by reactive oxidant species. Plants are sensitive to UV-B radiation, and this sensitivity can be even more clone-specific than species-specific. The results available in the literature for deciduous trees and shrubs indicate that UV-B radiation may affect several directions in the interaction of woody species with biotic (herbivores) and abiotic (CO 2 and nutrition) factors depending on the specific interaction in question. These multilevel interactions should have moderate ecological significance via the overall changed performance of woody species and shrubs. - The growth performance of deciduous trees and shrubs under UV-B irradiation is constrained by multilevel interactions with many abiotic and biotic factors

  6. Carbon dynamics in the deciduous broadleaf tree Erman's birch (Betula ermanii) at the subalpine treeline on Changbai Mountain, Northeast China.

    Science.gov (United States)

    Wang, Qing-Wei; Qi, Lin; Zhou, Wangming; Liu, Cheng-Gang; Yu, Dapao; Dai, Limin

    2018-01-01

    The growth limitation hypothesis (GLH) and carbon limitation hypothesis (CLH) are two dominant explanations for treeline formation. The GLH proposes that low temperature drives the treeline through constraining C sinks more than C sources, and it predicts that non-structural carbohydrate (NSC) levels are static or increase with elevation. Although the GLH has received strong support globally for evergreen treelines, there is still no consensus for deciduous treelines, which experience great asynchrony between supply and demand throughout the year. We investigated growth and the growing-season C dynamics in a common deciduous species, Erman's birch (Betula ermanii), along an elevational gradient from the closed forest to the treeline on Changbai Mountain, Northeast China. Samples were collected from developing organs (leaves and twigs) and main storage organs (stems and roots) for NSC analysis. Tree growth decreased with increasing elevation, and NSC concentrations differed significantly among elevations, organs, and sampling times. In particular, NSC levels varied slightly during the growing season in leaves, peaked in the middle of the growing season in twigs and stems, and increased continuously throughout the growing season in roots. NSCs also tended to increase or vary slightly in developing organs but decreased significantly in mature organs with increasing elevation. The decrease in NSCs with elevation in main storage organs indicates support for the CLH, while the increasing or static trends in new developing organs indicate support for the GLH. Our results suggest that the growth limitation theory may be less applicable to deciduous species' growth than to that of evergreen species. © 2018 Botanical Society of America.

  7. [Population structure and regeneration strategy of relict deciduous broadleaved trees on Mount Tianmu, Zhejiang Province, China.

    Science.gov (United States)

    Shang, Kan Kan; Chen, Bo; Da, Liang Jun

    2018-02-01

    The population structure, regeneration ways and spatial relationships of six relict deci-duous broadleaved trees were examined based on community investigation on Mount Tianmu, East China. The results showed that relict deciduous broadleaved trees had a strong ability of vegetative reproduction and their population structure was generally belonged to intermittent type. Some relict species such as Cyclocarya paliurus and Liquidamb aracalycina regenerated discontinuously at appropriate sites via long-distance diffusion. Some species such as Emmenoptery henryi and Euptelea pleiospermum regenerated discontinuously around mature trees due to habitat limitation and frequent disturbance. After occupying forest gaps by seedling regeneration, C. paliurus, L. acalycina, Nyssasinensis and Liquidambar formosana could recruit and form multi-stemmed individuals by their inherent sprouting ability at relatively stable sites such as crest slope and side slope. At riverbed, valley slope and head hollow, recognized as unstable habitats, Emmenopterys henryi, E. pleiospermum, and L. formosana could also recruit by strong sprouting ability due to sparse seedlings and individual loss incurred by disturbance. Therefore, the relict deciduous broadleaved trees could be classified into two ecological species groups (repairment species for forest gap and supplement species for special habitat) based on spatial distribution and strategy of regeneration and competition. We suggested that the protection of special habitats of their communities should be strengthened.

  8. In vitro propagation of katsura tree (Cercidiphyllum japonicum Sieb ...

    African Journals Online (AJOL)

    ajl5

    Katsura tree (Cercidiphyllum japonicum Sieb. Et Zucc) is a long-lived, deciduous, wind-pollinated tree with dimorphic leaves. It is valued as an ornamental or a shade tree for landscape and a commercially valuable tree. Conventional propagation through seeds and cutting is not sufficient to satisfy the progressive demand.

  9. Differences between height- and light-dependent changes in shoot traits in five deciduous tree species.

    Science.gov (United States)

    Osada, Noriyuki; Okabe, Yoshihiko; Hayashi, Daisuke; Katsuyama, Tomonori; Tokuchi, Naoko

    2014-01-01

    The effects of tree height on shoot traits may in some cases differ in magnitude and direction from the effects of light. Nevertheless, general patterns of change in shoot traits in relation to variations in height and light have not so far been revealed. A comprehensive analysis of the differences between the effects of height and light on a range of leaf and shoot traits is important for the scaling of these traits to individual trees. We investigated the biomass allocation and structure of current-year shoots at the top of the crowns of five deciduous tree species in Japan. Height effect was investigated by comparing shoot traits among trees of different heights growing under a high light environment. The effects of light were examined by comparing saplings growing in high- and low-light environments. The effects of light were significant for most traits, while those of height were not significant for some traits. The magnitudes of the effects of light were larger than those of height for most traits related to biomass allocation. There was an extreme difference between the effects of height and light in the direction of change in the length of current-year shoots and in the number of standing leaves. The measures of both parameters increased with the increase in light, but decreased with the increase in tree height. Thus, the effects of height and light on diverse traits at the level of current-year shoots were not always similar. These results suggest that great care must be taken when scaling shoot traits from small trees to tall trees because the effects of height and light can be complex.

  10. Estimating leaf area and leaf biomass of open-grown deciduous urban trees

    Science.gov (United States)

    David J. Nowak

    1996-01-01

    Logarithmic regression equations were developed to predict leaf area and leaf biomass for open-grown deciduous urban trees based on stem diameter and crown parameters. Equations based on crown parameters produced more reliable estimates. The equations can be used to help quantify forest structure and functions, particularly in urbanizing and urban/suburban areas.

  11. Flowering Trees

    Indian Academy of Sciences (India)

    deciduous tree with irregularly-shaped trunk, greyish-white scaly bark and milky latex. Leaves in opposite pairs are simple, oblong and whitish beneath. Flowers that occur in branched inflorescence are white, 2–. 3cm across and fragrant. Calyx is glandular inside. Petals bear numerous linear white scales, the corollary.

  12. Flowering Trees

    Indian Academy of Sciences (India)

    Celtis tetrandra Roxb. of Ulmaceae is a moderately large handsome deciduous tree with green branchlets and grayish-brown bark. Leaves are simple with three to four secondary veins running parallel to the mid vein. Flowers are solitary, male, female and bisexual and inconspicuous. Fruit is berry-like, small and globose ...

  13. Biomonitoring levels of airborne metals around Urmia Lake using deciduous trees and evaluation of their tolerance for greenbelt development.

    Science.gov (United States)

    Mohammadi, Amir; Mokhtari, Mehdi; Arani, Asghar Mosleh; Taghipour, Hassan; Hajizadeh, Yaghoub; Fallahzadeh, Hossein

    2018-05-16

    In the northwest of Iran, the dust of salty and toxic metals possibly caused due to drying Urmia Lake is threatening the health of surrounding communities. This study aimed to employ leaves of local deciduous trees for biomonitoring of toxic elements and to evaluate air pollution tolerance of the trees for greenbelt application. Sampling from leaves of four dominant tree species including Vitis vinifera, Juglans regia, Ulmus umbraculifera, and Popolus alba was carried out from gardens in two radial distances (5 and 10 km) around the Urmia Lake accounting for 16 sites. The concentration of metals in the leaves were extracted according to method USEPA method 3050B and measured by ICP AES technique. According to the levels of air pollution tolerance index (APTI), Popolus alba showed to be more sensitive to air pollution and can be applied for biomonitoring. The ranks of heavy metals and sodium concentrations in the leaves gained in the order of Na > Zn > Cu > Ni > Pb > As > Cd. The mean enrichment factor for the elements was calculated from 1 to 3, suggesting minor enrichment for them. As, Pb, and Na with similar spatial distribution were dominantly observed in northwest and center-east of the Urmia Lake. Potential ecological risk (PER) index showed a moderate risk in 6% of sampling zones, where Cd and As were identified as responsible pollutants. Principle component and correlation analysis between the elements depicted human sources such as industrial activity and road traffic for Cd, Cu, Ni, Pb, and Zn, whereas As and Na were most likely originated from the aerosols of Urmia Lake. Our findings showed that Popolus alba can be applied as a local biomonitor and Vitis vinifera with moderate tolerance can be used as a good air pollutant sink in greenbelt development around the drying Urmia Lake in the northwest of Iran.

  14. Flowering Trees

    Indian Academy of Sciences (India)

    sriranga

    Hook.f. ex Brandis (Yellow. Cadamba) of Rubiaceae is a large and handsome deciduous tree. Leaves are simple, large, orbicular, and drawn abruptly at the apex. Flowers are small, yellowish and aggregate into small spherical heads. The corolla is funnel-shaped with five stamens inserted at its mouth. Fruit is a capsule.

  15. Flowering Trees

    Indian Academy of Sciences (India)

    IAS Admin

    Aglaia elaeagnoidea (A.Juss.) Benth. of Meliaceae is a small-sized evergreen tree of both moist and dry deciduous forests. The leaves are alternate and pinnately compound, terminating in a single leaflet. Leaflets are more or less elliptic with entire margin. Flowers are small on branched inflorescence. Fruit is a globose ...

  16. Contrasting drivers and trends of coniferous and deciduous tree growth in interior Alaska.

    Science.gov (United States)

    Cahoon, Sean M P; Sullivan, Patrick F; Brownlee, Annalis H; Pattison, Robert R; Andersen, Hans-Erik; Legner, Kate; Hollingsworth, Teresa N

    2018-03-22

    The boreal biome represents approximately one third of the world's forested area and plays an important role in global biogeochemical and energy cycles. Numerous studies in boreal Alaska have concluded that growth of black and white spruce is declining as a result of temperature-induced drought stress. The combined evidence of declining spruce growth and changes in the fire regime that favor establishment of deciduous tree species has led some investigators to suggest the region may be transitioning from dominance by spruce to dominance by deciduous forests and/or grasslands. Although spruce growth trends have been extensively investigated, few studies have evaluated long-term radial growth trends of the dominant deciduous species (Alaska paper birch and trembling aspen) and their sensitivity to moisture availability. We used a large and spatially extensive sample of tree cores from interior Alaska to compare long-term growth trends among contrasting tree species (white and black spruce vs. birch and aspen). All species showed a growth peak in the mid-1940s, although growth following the peak varied strongly across species. Following an initial decline from the peak, growth of white spruce showed little evidence of a trend, while black spruce and birch growth showed slight growth declines from ~1970 to present. Aspen growth was much more variable than the other species and showed a steep decline from ~1970 to present. Growth of birch, black and white spruce was sensitive to moisture availability throughout most of the tree-ring chronologies, as evidenced by negative correlations with air temperature and positive correlations with precipitation. However, a positive correlation between previous July precipitation and aspen growth disappeared in recent decades, corresponding with a rise in the population of the aspen leaf miner (Phyllocnistis populiella), an herbivorous moth, which may have driven growth to a level not seen since the early 20th century. Our results

  17. Dry-air drying at room temperature - a practical pre-treatment method of tree leaves for quantitative analyses of phenolics?

    Science.gov (United States)

    Tegelberg, Riitta; Virjamo, Virpi; Julkunen-Tiitto, Riitta

    2018-03-09

    In ecological experiments, storage of plant material is often needed between harvesting and laboratory analyses when the number of samples is too large for immediate, fresh analyses. Thus, accuracy and comparability of the results call for pre-treatment methods where the chemical composition remains unaltered and large number of samples can be treated efficiently. To study if a fast dry-air drying provides an efficient pre-treatment method for quantitative analyses of phenolics. Dry-air drying of mature leaves was done in a drying room equipped with dehumifier (10% relative humidity, room temperature) and results were compared to freeze-drying or freeze-drying after pre-freezing in liquid nitrogen. The quantities of methanol-soluble phenolics of Betula pendula Roth, Betula pubescens Ehrh., Salix myrsinifolia Salisb., Picea abies L. Karsten and Pinus sylvestris L. were analysed with HPLC and condensed tannins were analysed using the acid-butanol test. In deciduous tree leaves (Betula, Salix), the yield of most of the phenolic compounds was equal or higher in samples dried in dry-air room than the yield from freeze-dried samples. In Picea abies needles, however, dry-air drying caused severe reductions in picein, stilbenes, condensed tannin and (+)-catechin concentrations compared to freeze-drying. In Pinus sylvestris highest yields of neolignans but lowest yields of acetylated flavonoids were obtained from samples freeze-dried after pre-freezing. Results show that dry-air drying provides effective pre-treatment method for quantifying the soluble phenolics for deciduous tree leaves, but when analysing coniferous species, the different responses between structural classes of phenolics should be taken into account. Copyright © 2018 John Wiley & Sons, Ltd.

  18. P{owering 'Trees

    Indian Academy of Sciences (India)

    Melia dubia Cav. of Meliaceae is a large deciduous tree. Leaves are compound with toothed leaflets. Flowers are small, greenish-yellow in much-branched inflorescences. Fruits are green, ellipsoidal with a single seed covered by hard portion ( as in a mango fruit) and surrounded by fleshy pulp outside. The bark is bitter ...

  19. Tree Death Not Resulting in Gap Creation: An Investigation of Canopy Dynamics of Northern Temperate Deciduous Forests

    Directory of Open Access Journals (Sweden)

    Jean-Francois Senécal

    2018-01-01

    Full Text Available Several decades of research have shown that canopy gaps drive tree renewal processes in the temperate deciduous forest biome. In the literature, canopy gaps are usually defined as canopy openings that are created by partial or total tree death of one or more canopy trees. In this study, we investigate linkages between tree damage mechanisms and the formation or not of new canopy gaps in northern temperate deciduous forests. We studied height loss processes in unmanaged and managed forests recovering from partial cutting with multi-temporal airborne Lidar data. The Lidar dataset was used to detect areas where canopy height reduction occurred, which were then field-studied to identify the tree damage mechanisms implicated. We also sampled the density of leaf material along transects to characterize canopy structure. We used the dataset of the canopy height reduction areas in a multi-model inference analysis to determine whether canopy structures or tree damage mechanisms most influenced the creation of new canopy gaps within canopy height reduction areas. According to our model, new canopy gaps are created mainly when canopy damage enlarges existing gaps or when height is reduced over areas without an already established dense sub-canopy tree layer.

  20. Ficus religiosa L. (English: Peepal tree or sacred fig; Hindi: Pippal ...

    Indian Academy of Sciences (India)

    Ficus religiosa L. (English: Peepal tree or sacred fig; Hindi: Pippal) of Moraceae is a large deciduous tree that grows wild as well as cultivated. The picture shows the tree with fresh flush of leaves. The tree is planted chiefly near the temples by Hindus and Buddhists who regard it as sacred. The characteristic heart-shaped ...

  1. Structural Relationships Of Selected Tree Species at Several Mid-Latitude Deciduous Forest Sites in Virginia

    Science.gov (United States)

    1999-09-01

    are included in the deciduous analyses. They are mockernut hickory { Carya tomentosa), American elm {Ulmus americana), pecan { Carya illinoensis ), and...alba, white ash (Fraxinus americana), and pecan ( Carya illinoensis ). A number of these trees have plaques indicating the dates of planting (late 1700s

  2. Midwest community tree guide: benefits, costs, and strategic planting

    Science.gov (United States)

    E. Gregory McPherson; James R. Simpson; Paula J. Peper; Scott E. Maco; Shelley L. Gardner; Shauna K. Cozad; Qingfu Xiao

    2006-01-01

    This report quantifies benefits and costs for typical small, medium, and large deciduous (losing their leaves every autumn) trees: crabapple, red oak, and hackberry (see "Common and Scientific Names" section). The analysis assumed that trees were planted in a residential yard or public site (streetside or park) with a 60 percent survival rate over a 40-year...

  3. Dust retaining properties of leaves of some tree species

    Energy Technology Data Exchange (ETDEWEB)

    Gusev, M I

    1960-05-01

    A study was made in Tashkent, Russia of the dust-retaining power of leaves of several tree species. Investigations were made in a park where these tree species were growing in close proximity, exposed to the effects of dust from the main city street and from the highway passing through the park. Observations on the dust-retaining power of leaves were made mostly during the summer and fall months. The dust-retaining power of leaves of different tree species varied with the dust concentration in the air. In the summer and fall when rains are scarce a steady accumulation of dust was observed on the surface of the leaves. 1 table.

  4. Determining past leaf-out times of New England's deciduous forests from herbarium specimens.

    Science.gov (United States)

    Everill, Peter H; Primack, Richard B; Ellwood, Elizabeth R; Melaas, Eli K

    2014-08-01

    • There is great interest in studying leaf-out times of temperate forests because of the importance of leaf-out in controlling ecosystem processes, especially in the face of a changing climate. Remote sensing and modeling, combined with weather records and field observations, are increasing our knowledge of factors affecting variation in leaf-out times. Herbarium specimens represent a potential new source of information to determine whether the variation in leaf-out times observed in recent decades is comparable to longer time frames over past centuries.• Here we introduce the use of herbarium specimens as a method for studying long-term changes in leaf-out times of deciduous trees. We collected historical leaf-out data for the years 1834-2008 from common deciduous trees in New England using 1599 dated herbarium specimens with young leaves.• We found that leaf-out dates are strongly affected by spring temperature, with trees leafing out 2.70 d earlier for each degree C increase in mean April temperature. For each degree C increase in local temperature, trees leafed out 2.06 d earlier. Additionally, the mean response of leaf-out dates across all species and sites over time was 0.4 d earlier per decade. Our results are of comparable magnitude to results from studies using remote sensing and direct field observations.• Across New England, mean leaf-out dates varied geographically in close correspondence with those observed in studies using satellite data. This study demonstrates that herbarium specimens can be a valuable source of data on past leaf-out times of deciduous trees. © 2014 Botanical Society of America, Inc.

  5. Scale insects and mealy bugs (Homoptera: Coccoidea) attacking deciduous fruit trees in the western north coast of Alexandria, Egypt.

    Science.gov (United States)

    Mourad, A K; Moursi Khadiga, S; Mesbah, H A; Abdel-Razak Soad, I

    2008-01-01

    This investigation covered a survey of scale insects and mealy bugs infesting ten growing species of deciduous fruit trees in three localities in Alexandria govemorate. These localities were Merghem, Burg El-Arab, and El-Nahda about 50 Km. West of Alexandria under both rain-fed and irrigation system conditions. The common inspected fruit trees were fig, white mulberry, pomegranate, apple, pear, apricot, European plum, peach, almond, and persimmon. It was shown that a group of twenty scale insects and meaty bug species pertaining to fifteen genera belonging to six families of the super family: Coccoidea were collected and identified during the elapsing period from January to December, 2004. Among these species, Diaspidiotus perniciosus (Comstock) was recorded for the first time in Egypt. In the present study, many insect and non-insect parasitoids and predators were also found associated with these scale insects and mealy bugs on deciduous fruit trees in the three concerned localities throughout this investigation. These natural enemies were identified and recorded.

  6. Rubber trees demonstrate a clear retranslocation under seasonal drought and cold stresses

    Directory of Open Access Journals (Sweden)

    Yuwu Li

    2016-12-01

    Full Text Available Having been introduced to the northern edge of Asian tropics, the rubber tree (Hevea brasiliensis has become deciduous in this climate with seasonal drought and cold stresses. To determine its internal nutrient strategy during leaf senescence and deciduous periods, we investigated mature leaf and senescent leaf nutrients, water-soluble soil nutrients and characteristics of soil microbiota in nine different ages of monoculture rubber plantations. Rubber trees demonstrate complicated retranslocation of N, P and K during foliar turnover. Approximately 50.26% of leaf nutrients and 21.47% of soil nutrients were redistributed to the rubber tree body during the leaf senescence and withering stages. However, no significant changes in the structure- or function-related properties of soil microbes were detected. These nutrient retranslocation strategy may be important stress responses. In the nutrient retranslocation process, soil plays a dual role as nutrient supplier and nutrient bank. Soil received the nutrients from abscissed leaves, and also supplied nutrients to trees in the non-growth stage. Nutrient absorption and accumulation began before the leaves started to wither and fall.

  7. STRUCTURE, COMPOSITION AND USE OF TREES OF THE DECIDUOUS FOREST IN APATZINGAN, MICHOACAN

    Directory of Open Access Journals (Sweden)

    F. Casanova-Lugo

    2014-08-01

    Full Text Available The aim of this study was to determine the structure, composition and use of trees and shrubs of tropical deciduous forest in the mountains of Apatzingán, Michoacan. For this, six sampling units were established and each 7 sub-plots (squares of 10 × 10 m were delineated. A floristic inventory was conducted and diameter at breast height (DBH, total height (TH, crown diameter (CD, (BA basal area and the importance value index (IVI was determined. Further, based on local knowledge the use of each species found was determined. The results show that 97.1 % of species having a DAP ≤ 10 cm. Over 90% of the sampled trees had a DC ≤ 4 m. 84.4 % of the sampled individuals had an AT ≤ 6 m, and 85 % of species had an AB ≤ 30 cm2. The species most IVI were Cordia elaeagnoides, Randia watsoni, Apoplanesia paniculate, Caesalpinia platyloba, Capparis asperifolia and Triunfetta sp. 38% of the sampled species belong to the legume family and almost 80% of the sampled species has forage use. We conclude that local knowledge of the species of deciduous forest can help establish the basis for designing new proposals to the use and conservation of local resources and generate resilient livestock production systems. Â

  8. Unmanned aerial survey of fallen trees in a deciduous broadleaved forest in eastern Japan.

    Science.gov (United States)

    Inoue, Tomoharu; Nagai, Shin; Yamashita, Satoshi; Fadaei, Hadi; Ishii, Reiichiro; Okabe, Kimiko; Taki, Hisatomo; Honda, Yoshiaki; Kajiwara, Koji; Suzuki, Rikie

    2014-01-01

    Since fallen trees are a key factor in biodiversity and biogeochemical cycling, information about their spatial distribution is of use in determining species distribution and nutrient and carbon cycling in forest ecosystems. Ground-based surveys are both time consuming and labour intensive. Remote-sensing technology can reduce these costs. Here, we used high-spatial-resolution aerial photographs (0.5-1.0 cm per pixel) taken from an unmanned aerial vehicle (UAV) to survey fallen trees in a deciduous broadleaved forest in eastern Japan. In nine sub-plots we found a total of 44 fallen trees by ground survey. From the aerial photographs, we identified 80% to 90% of fallen trees that were >30 cm in diameter or >10 m in length, but missed many that were narrower or shorter. This failure may be due to the similarity of fallen trees to trunks and branches of standing trees or masking by standing trees. Views of the same point from different angles may improve the detection rate because they would provide more opportunity to detect fallen trees hidden by standing trees. Our results suggest that UAV surveys will make it possible to monitor the spatial and temporal variations in forest structure and function at lower cost.

  9. Upscaling from leaf to canopy chlorophyll/carotenoid pigment based vegetation indices reveal phenology of photosynthesis in temperate evergreen and deciduous trees

    Science.gov (United States)

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

    2017-12-01

    Optically derived vegetation indices have been developed to provide information about plant status including photosynthetic activity. They reflect changes in leaf pigments, which vary seasonally in pigment composition, enabling them to be used as a proxy of photosynthetic phenology. Important pigments in photosynthetic activity are carotenoids and chlorophylls, which are associated with light harvesting and energy dissipation. In temperate forests, which consist of deciduous and evergreen trees, there are difficulties resolving evergreen phenology using the most widely used index, the normalized difference vegetation index (NDVI). NDVI works well in deciduous trees, which exhibit a "visible" phenological process of leaf growth in the spring, and leaf senescence and abscission in the autumn. Evergreen conifers stay green year-round and utilize "invisible" changes of overwintering pigment composition that NDVI cannot resolve, so carotenoid pigment sensitive vegetation indices have been suggested for evergreens. The aim of this study was to evaluate carotenoid based vegetation indices over the chlorophyll sensitive NDVI. For this purpose, we evaluated the greenness index, NDVI, and carotenoid pigment sensitive indices: photochemical reflectance index (PRI) and chlorophyll/carotenoid index (CCI) in red maple, white oak and eastern white pine for two years. We also measured leaf gas exchange and pigment concentrations. We observed that NDVI correlated with photosynthetic activity in deciduous trees, whereas PRI and CCI correlated with photosynthesis across both evergreen and deciduous trees. This pattern was consistent, upscaling from leaf- to canopy-scales indicating that the mechanisms involved in winter acclimation can be resolved at larger spatial scales. PRI and CCI detected seasonal changes in carotenoids and chlorophylls linked to photoprotection and are suitable as a proxy of photosynthetic activity. These findings have implications to improve our use and

  10. Tectona grandis L. f (the teak tree; Hindi: Sagallll or Segllll) (~r ...

    Indian Academy of Sciences (India)

    Tectona grandis L. f (the teak tree; Hindi: Sagallll or Segllll) (~r Verhell({Ceae is a large deciduous tree cllitivatedfor its timber. Leaves are large; flmvers are small, white, svveet-scented and borne on highly branched inflorescences. Fruit is hard and enveloped by bladder-like cal.vx. The timber is one of the best for all wood ...

  11. A method of detecting carbonyl compounds in tree leaves in China.

    Science.gov (United States)

    Huang, Juan; Feng, Yanli; Fu, Jiamo; Sheng, Guoying

    2010-06-01

    Carbonyl compounds have been paid more and more attention because some carbonyl species have been proven to be carcinogenic or a risk for human health. Plant leaves are both an important emission source and an important sink of carbonyl compounds. But the research on carbonyl compounds from plant leaves is very scarce. In order to make an approach to the emission mechanism of plant leaves, a new method was established to extract carbonyl compounds from fresh plant leaves. The procedure combining derivatization with ultrasonication was developed for the fast extraction of carbonyl compounds from tree leaves. Fresh leaves (Metasequoia glyptostroboides), were selected and extracted by this method. Seven carbonyl compounds, including formaldehyde, acetaldehyde, acetone, acrolein, p-tolualdehyde, m/o-tolualdehyde, and hexaldehyde were determined and quantified. The most common carbonyl species of the four tree leaves were formaldehyde, acrolein, and m/o-tolualdehyde. They accounted for 67.3% in cedar, 50.8% in sweet olive, 45.8% in dawn redwood, and 44.6% in camphor tree, respectively. Camphor tree had the highest leaf level of m/o-tolualdehyde with 15.0 +/- 3.4 microg g(-1)(fresh leaf weight), which indicated that camphor tree may be a bioindicator of the level of tolualdehyde or xylene in the atmosphere. By analyzing carbonyl compounds from different tree leaves, it is not only helpful for further studying the relationship between sink and emission of carbonyls from plants, but also helpful for exploring optimum plant population in urban greening.

  12. Low host-tree preferences among saproxylic beetles : acomparison of four deciduous species

    OpenAIRE

    Milberg, Per; Bergman, Karl-Olof; Johansson, Helena; Jansson, Nicklas

    2014-01-01

    Many wood-dwelling beetles rely on old hollow trees. In Europe, oaks are known to harbour a species-rich saproxylic beetle fauna, while less is known regarding other broad-leaved tree species. Furthermore, the extent to which saproxylic insect species have specialised on different tree species remains unknown. In this study, we sampled beetles through pitfall traps and window traps in four different tree species in a landscape with many old oaks. We recorded 242 saproxylic beetle species of w...

  13. Long term radiocesium contamination of fruit trees following the Chernobyl accident.

    Science.gov (United States)

    Antonopoulos-Domis, M; Clouvas, A; Gagianas, A

    1996-12-01

    Radiocesium contamination from the Chernobyl accident of fruits and leaves from various fruit trees was systematically studied from 1990 to 1995 on two agricultural experimentation farms in Northern Greece. The results are discussed in the framework of a previously published model describing the long-term radiocesium contamination mechanism of deciduous fruit trees after a nuclear accident. The results of the present work qualitatively verify the model predictions.

  14. [Parameter optimization of BEPS model based on the flux data of the temperate deciduous broad-leaved forest in Northeast China.

    Science.gov (United States)

    Lu, Wei; Fan, Wen Yi; Tian, Tian

    2016-05-01

    Keeping other parameters as empirical constants, different numerical combinations of the main photosynthetic parameters V c max and J max were conducted to estimate daily GPP by using the iteration method in this paper. To optimize V c max and J max in BEPSHourly model at hourly time steps, simulated daily GPP using different numerical combinations of the parameters were compared with the flux tower data obtained from the temperate deciduous broad-leaved forest of the Maoershan Forest Farm in Northeast China. Comparing the simulated daily GPP with the observed flux data in 2011, the results showed that optimal V c max and J max for the deciduous broad-leaved forest in Northeast China were 41.1 μmol·m -2 ·s -1 and 82.8 μmol·m -2 ·s -1 respectively with the minimal RMSE and the maximum R 2 of 1.10 g C·m -2 ·d -1 and 0.95. After V c max and J max optimization, BEPSHourly model simulated the seasonal variation of GPP better.

  15. Long term radiocesium contamination of fruit trees following the Chernobyl accident

    International Nuclear Information System (INIS)

    Antonopoulos-Domis, M.; Clouvas, A.; Gagianas, A.

    1996-01-01

    Radiocesium contamination form the Chernobyl accident of fruits and leaves from various fruit trees was systematically studied form 1990-1995 on two agricultural experimentation farms in Northern Greece. The results are discussed in the framework of a previously published model describing the long-term radiocesium contamination mechanism of deciduous fruit trees after a nuclear accident. The results of the present work qualitatively verify the model predictions. 11 refs., 5 figs., 1 tab

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

    DEFF Research Database (Denmark)

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

    2015-01-01

    It has been recognized for a long time that the overstorey composition of a forest partly determines its biological and physical-chemical functioning. Here, we review evidence of the influence of evergreen gymnosperm (EG) tree species and deciduous angiosperm (DA) tree species on the water balance...... 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...

  17. Isotope studies to determine dry deposition of sulfate to deciduous and coniferous trees: Final draft

    International Nuclear Information System (INIS)

    Garten, C.T. Jr.

    1988-01-01

    Experiments have been conducted at two locations near Oak Ridge, Tennessee, with radioactive 35 S (87 day half-life) to examine the cycling behavior of sulfur in yellow poplar (Liriodendron tulipifera), red maple (Acer rubrum), and loblolly pine (Pinus taeda) trees. Some findings pertain to methods development for estimating dry deposition of sulfur to forest canopies and the magnitude of sulfur emissions from natural sources (Task II). We will determine through field studies, the internal cycling, storage, and biogenic emission of sulfur, as traced by 35 SO 4 2- , in environments impacted by atmospheric sulfate deposition; and will determine through isotope dilution studies, the contribution of foliar leaching and dry deposition to net throughfall (NTF) sulfate concentrations beneath deciduous and coniferous trees in such environments. 3 refs., 2 figs., 1 tab

  18. Seasonal variations of gas exchange and water relations in deciduous and evergreen trees in monsoonal dry forests of Thailand.

    Science.gov (United States)

    Ishida, Atsushi; Harayama, Hisanori; Yazaki, Kenichi; Ladpala, Phanumard; Sasrisang, Amornrat; Kaewpakasit, Kanokwan; Panuthai, Samreong; Staporn, Duriya; Maeda, Takahisa; Gamo, Minoru; Diloksumpun, Sapit; Puangchit, Ladawan; Ishizuka, Moriyoshi

    2010-08-01

    This study compared leaf gas exchange, leaf hydraulic conductance, twig hydraulic conductivity and leaf osmotic potential at full turgor between two drought-deciduous trees, Vitex peduncularis Wall. and Xylia xylocarpa (Roxb.) W. Theob., and two evergreen trees, Hopea ferrea Lanessan and Syzygium cumini (L.) Skeels, at the uppermost canopies in tropical dry forests in Thailand. The aims were to examine (i) whether leaf and twig hydraulic properties differ in relation to leaf phenology and (ii) whether xylem cavitation is a determinant of leaf shedding during the dry season. The variations in almost all hydraulic traits were more dependent on species than on leaf phenology. Evergreen Hopea exhibited the lowest leaf-area-specific twig hydraulic conductivity (leaf-area-specific K(twig)), lamina hydraulic conductance (K(lamina)) and leaf osmotic potential at full turgor (Ψ(o)) among species, whereas evergreen Syzygium exhibited the highest leaf-area-specific K(twig), K(lamina) and Ψ(o). Deciduous Xylia had the highest sapwood-area-specific K(twig), along with the lowest Huber value (sapwood area/leaf area). More negative osmotic Ψ(o) and leaf osmotic adjustment during the dry season were found in deciduous Vitex and evergreen Hopea, accompanied by low sapwood-area-specific K(twig). Regarding seasonal changes in hydraulics, no remarkable decrease in K(lamina) and K(twig) was found during the dry season in any species. Results suggest that leaf shedding during the dry season is not always associated with extensive xylem cavitation.

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

    Science.gov (United States)

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

    2017-06-01

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

  20. Atmospheric deposition in coniferous and deciduous tree stands in Poland

    Science.gov (United States)

    Kowalska, Anna; Astel, Aleksander; Boczoń, Andrzej; Polkowska, Żaneta

    2016-05-01

    The objective of this study was to assess the transformation of precipitation in terms of quantity and chemical composition following contact with the crown layer in tree stands with varied species composition, to investigate the effect of four predominant forest-forming species (pine, spruce, beech, and oak) on the amount and composition of precipitation reaching forest soils, and to determine the sources of pollution in atmospheric precipitation in forest areas in Poland. The amount and chemical composition (pH, electric conductivity, alkalinity, and chloride, nitrate, sulfate, phosphate, ammonium, calcium, magnesium, sodium, potassium, iron aluminum, manganese, zinc, copper, total nitrogen, and dissolved organic carbon contents) of atmospheric (bulk, BP) and throughfall (TF) precipitation were studied from January to December 2010 on twelve forest monitoring plots representative of Polish conditions. The study results provided the basis for the determination of the fluxes of pollutants in the forest areas of Poland and allowed the comparison of such fluxes with values provided in the literature for European forest areas. The transformation of precipitation in the canopy was compared for different tree stands. The fluxes of substances in an open field and under canopy were influenced by the location of the plot, including the regional meteorological conditions (precipitation amounts), vicinity of the sea (effect of marine aerosols), and local level of anthropogenic pollution. Differences between the plots were higher in TF than in BP. The impact of the vegetation cover on the chemical composition of precipitation depended on the region of the country and dominant species in a given tree stand. Coniferous species tended to cause acidification of precipitation, whereas deciduous species increased the pH of TF. Pine and oak stands enriched precipitation with components that leached from the canopy (potassium, manganese, magnesium) to a higher degree than spruce and

  1. Effects of Warming on Tree Species’ Recruitment in Deciduous Forests of the Eastern United States

    Energy Technology Data Exchange (ETDEWEB)

    Melillo, Jerry M. [Marine Biological Lab., Woods Hole, MA (United States); Clark, James S. [Duke Univ., Durham, NC (United States); Mohan, Jacqueline [Univ. of Georgia, Athens, GA (United States)

    2015-03-25

    Climate change is restructuring forests of the United States, although the details of this restructuring are currently uncertain. Rising temperatures of 2 to 8oC and associated changes in soil moisture will shift the competitive balance between species that compete for light and water, and so change their abilities to produce seed, germinate, grow, and survive. We have used large-scale experiments to determine the effects of warming on the most sensitive stage of species distributions, i.e., recruitment, in mixed deciduous forests in southern New England and in the Piedmont region of North Carolina. Two questions organized our research: (1) Might temperate tree species near the “warm” end of their range in the eastern United States decline in abundance during the coming century due to projected warming? and (2) Might trees near the “cool” end of their range in the eastern United States increase in abundance, or extend their range, during the coming 100 years because of projected warming? To explore these questions, we exposed seedlings to air and soil warming experiments in two eastern deciduous forest sites; one at the Harvard Forest (HF) in central Massachusetts, and the other at the Duke Forest (DF) in the Piedmont region of North Carolina. We focused on tree species common to both Harvard and Duke Forests (such as red, black, and white oaks), those near northern range limits (black oak, flowing dogwood, tulip poplar), and those near southern range limits (yellow birch, sugar maple, Virginia pine). At each site, we planted seeds and seedlings in common gardens established in temperature-controlled, open-top chambers. The experimental design was replicated and fully factorial and involved three temperature regimes (ambient, +3oC and +5oC) and two light regimes (closed forest canopy (low light) and gap conditions (high light)). Measured variables included Winter/Spring responses to temperature and mid-Summer responses to low soil moisture. This research

  2. Changes of main secondary metabolites in leaves of Ginkgo biloba in response to ozone fumigation

    Institute of Scientific and Technical Information of China (English)

    HE Xingyuan; HUANG Wei; CHEN Wei; DONG Tian; LIU Changbing; CHEN Zhenju; XU Sheng; RUAN Yanan

    2009-01-01

    To investigate the effect of elevated O3 on the accumulation of main secondary metabolites in leaves of Ginkgo biloba L., four-year-old trees were exposed in open-top chambers with ambient air and the air with twice ambient O3 concentration in Shenyang in 2006.Elevated O3 increased the concentrations of terpenes, but decreased the concentrations of phenolics in G.biloba leaves.The results showed that secondary compounds from G.biloba leaves responded to the elevated O3 exposure in a different way when compared to previous studies which showed elevated O3 increased the concentrations of phenolics but had no effect on the terpenes in leaves of other deciduous trees.Furthermore, reduced synthesis of phenolics may decrease the resistance of G.biloba to O3 and other environmental factors.On the other hand, the induced synthesis of terpenes may enhance the antioxidant abilities in G.biloba leaves at the end of O3 fumigation.

  3. [Spectrum Variance Analysis of Tree Leaves Under the Condition of Different Leaf water Content].

    Science.gov (United States)

    Wu, Jian; Chen, Tai-sheng; Pan, Li-xin

    2015-07-01

    Leaf water content is an important factor affecting tree spectral characteristics. So Exploring the leaf spectral characteristics change rule of the same tree under the condition of different leaf water content and the spectral differences of different tree leaves under the condition of the same leaf water content are not only the keys of hyperspectral vegetation remote sensing information identification but also the theoretical support of research on vegetation spectrum change as the differences in leaf water content. The spectrometer was used to observe six species of tree leaves, and the reflectivity and first order differential spectrum of different leaf water content were obtained. Then, the spectral characteristics of each tree species leaves under the condition of different leaf water content were analyzed, and the spectral differences of different tree species leaves under the condition of the same leaf water content were compared to explore possible bands of the leaf water content identification by hyperspectral remote sensing. Results show that the spectra of each tree leaf have changed a lot with the change of the leaf water content, but the change laws are different. Leaf spectral of different tree species has lager differences in some wavelength range under the condition of same leaf water content, and it provides some possibility for high precision identification of tree species.

  4. Carbon and Nitrogen dynamics in deciduous and broad leaf trees under drought stress

    Science.gov (United States)

    Joseph, Jobin; Schaub, Marcus; Arend, Matthias; Saurer, Matthias; siegwolf, Rolf; Weiler, Markus; Gessler, Arthur

    2017-04-01

    Climate change is projected to lead to an increased frequency and duration of severe drought events in future. Already within the last twenty years, however, drought stress related forest mortality has been increasing across the globe. Tree and forest die off events have multiple adverse effects on ecosystem functioning and might convert previous carbon sinks to act as carbon sources instead and can thus intensify the effect of climate change and global warming. Current predictions of forest's functioning under drought and thus forest mortality under future climatic conditions are constrained by a still incomplete picture of the trees' physiological reactions that allows some trees to survive drought periods while others succumb. Concerning the effects of drought on the carbon balance and on tree hydraulics our picture is getting more complete, but still interactions between abiotic factors and pest and diseases as well as the interaction between carbon and nutrient balances as factors affecting drought induced mortality are not well understood. Reduced carbon allocation from shoots to roots might cause a lack of energy for root nutrient uptake and to a shortage of carbon skeletons for nitrogen assimilation and thus to an impaired nutrient status of trees. To tackle these points, we have performed a drought stress experiment with six different plant species, 3 broad leaf (maple, beech and oak) and 3 deciduous (pine, fir and spruce). Potted two-year-old seedlings were kept inside a greenhouse for 5 months and 3 levels of drought stress (no stress (control), intermediate and intensive drought stress) were applied by controlling water supply. Gas exchange measurements were performed periodically to monitor photosynthesis, transpiration, stomatal conductance. At the pinnacle of drought stress, we applied isotopic pulse labelling: On the one hand we exposed trees to 13CO2 to investigate on carbon dynamics and the allocation of new assimilates within the plant. Moreover

  5. Spanning trees with many leaves: new extremal results and an improved FPT algorithm

    NARCIS (Netherlands)

    Bonsma, P.S.

    We present two lower bounds for the maximum number of leaves in a spanning tree of a graph. For connected graphs without triangles, with minimum degree at least three, we show that a spanning tree with at least (n+4)/3 leaves exists, where n is the number of vertices of the graph. For connected

  6. Microclimate, Water Potential, Transpiration, and Bole Dielectric Constant of Coniferous and Deciduous Tree Species in the Continental Boreal Ecotone of Central Alaska

    Science.gov (United States)

    Zimmermann, R.; McDonald, K.; Way, J.; Oren, R.

    1994-01-01

    Tree canopy microclimate, xylem water flux and xylem dielectric constant have been monitored in situ since June 1993 in two adjacent natural forest stands in central Alaska. The deciduous stand represents a mature balsam poplar site on the Tanana River floodplain, while the coniferous stand consists of mature white spruce with some black spruce mixed in. During solstice in June and later in summer, diurnal changes of xylem water potential were measured to investigate the occurrence and magnitude of tree transpiration and dielectric constant changes in stems.

  7. Specific and generic stem biomass and volume models of tree species in a West African tropical semi-deciduous forest

    DEFF Research Database (Denmark)

    Goussanou, Cédric A.; Guendehou, Sabin; Assogbadjo, Achille E.

    2016-01-01

    The quantification of the contribution of tropical forests to global carbon stocks and climate change mitigation requires availability of data and tools such as allometric equations. This study made available volume and biomass models for eighteen tree species in a semi-deciduous tropical forest...... in West Africa. Generic models were also developed for the forest ecosystem, and basic wood density determined for the tree species. Non-destructive sampling approach was carried out on five hundred and one sample trees to analyse stem volume and biomass. From the modelling of volume and biomass...... enabled to conclude that the non-destructive sampling was a good approach to determining reliable basic wood density. The comparative analysis of species-specific models in this study with selected generic models for tropical forests indicated low probability to identify effective generic models with good...

  8. Tree growth studies on uranium mill tailings

    International Nuclear Information System (INIS)

    Murray, D.R.; Turcotte, M.

    1982-01-01

    Coniferous trees planted in 1974 and deciduous species that have volunteered since 1970 on uranium mill tailings that had been stabilized to varying degrees using limestone and vegetation were evaluated. Their survival and growth rates were compared with those from other investigations. Competition for light appears to be a major contributor to mortality. Differences in soil moisture conditions under a tree stand as compared to those under a grass sward are potentially significant enough to affect the tailings hydrology and effluent contamination. Recommendations include planting seeds of deciduous species or deciduous and coniferous seedlings on strips of freshly disturbed tailings. The disturbed strips would provide reduced competition for the initial year and assist in tree survival. The planting of block stands of coniferous or deciduous trees would be useful for evaluating the hydrological impact of the trees as compared to the present grass sward

  9. Potential sources of methylmercury in tree foliage

    International Nuclear Information System (INIS)

    Tabatchnick, Melissa D.; Nogaro, Géraldine; Hammerschmidt, Chad R.

    2012-01-01

    Litterfall is a major source of mercury (Hg) and toxic methylmercury (MeHg) to forest soils and influences exposures of wildlife in terrestrial and aquatic ecosystems. However, the origin of MeHg associated with tree foliage is largely unknown. We tested the hypothesis that leaf MeHg is influenced by root uptake and thereby related to MeHg levels in soils. Concentrations of MeHg and total Hg in deciduous and coniferous foliage were unrelated to those in soil at 30 urban and rural forested locations in southwest Ohio. In contrast, tree genera and trunk diameter were significant variables influencing Hg in leaves. The fraction of total Hg as MeHg averaged 0.4% and did not differ among tree genera. Given that uptake of atmospheric Hg 0 appears to be the dominant source of total Hg in foliage, we infer that MeHg is formed by in vivo transformation of Hg in proportion to the amount accumulated. - Highlights: ► Levels of methylmercury and total Hg in foliage were unrelated to those in soil. ► Methylmercury:total Hg ratio in leaves did not differ among nine tree genera. ► Hg in foliage varied inversely with trunk diameter, a proxy for respiration. ► Methylmercury in leaves may result from in vivo methylation of atmospheric Hg. - Methylmercury in tree foliage appears to result from in vivo methylation of mercury accumulated from the atmosphere.

  10. Storage and recycling utilization of leaf-nitrogen of jujube tree

    International Nuclear Information System (INIS)

    Zeng Xiang; Hao Zhongning

    1991-01-01

    16 N-urea was foliarly applied on bearing or young jujube tree in autumn of 1987. The effects of leaf-nitrogen retranslocation in the trees, positions of the N stored, forms of reserved N, and reutilization of storage N in the next year were studied. The results were as follows: 15 N returned and stored in all parts of the tree following foliar application of 15 N-urea. Root could use the nitrogen not only absorbed from soil but also transported from leaves. The above-ground organs and roots of jujube tree played the same important roles on nitrogen storage in winter. The main forms of storage nitrogen were protein-N, which was 2-3 fold more than non-protein-N. The storage nitrogen existed in above-ground parts was used first in early spring, and that returned from leaves last year could be prior used for the developments of leaves, branchlets and infloresences. The relative distribution of nitrogen in floresence was more in bearing tree than in young tree. In the next year, 15 N was redistributed in branchlets, leaves, flowers, young fruits and perennial spurs in autumn. The 15 N transported out of the treated spurs reappeared in next spring and further transported to neighboring spurs. The local storage N was prior used for growth. There was 21.49% of fertilizer-N stored in the young jujube trees when treated foliarly with urea in autumn of 1987. After one years's use, there was still 18.91% of fertilizer-N existed in the trees, which indicated a characteristic of circulatory utilization of nitrogen for a long period and the reutilized nitrogen was mainly from jujube leaves and deciduous branchlets

  11. Understanding of amount and dynamics of radioactive cesium deposited on trees in Fukushima

    Energy Technology Data Exchange (ETDEWEB)

    Endo, Izuki; Ohte, Nobuhito; Iseda, Kohei; Tanoi, Keitaro; Hirose, Atsushi; Kobayashi, Natsuko I. [The University of Tokyo, 113-8657, 1-1-1 Yayoi Bunkyo-ku, Tokyo (Japan); Ishii, Nobuyoshi [National Institute of Radiological Sciences, 263-8555, 4-9-1 Anagawa, Inage-ku, Chiba-shi, Chiba (Japan); Ohashi, Mizue [University of Hyogo, 670-0092, 1-1-12 Shinzaike-Honcho, Himeji, Hyogo (Japan)

    2014-07-01

    higher than the heartwood. These results indicate that considerable amount of {sup 137}Cs has been already accumulated into wood of C. japonica. {sup 137}Cs may be absorbed from bark and/or from root. The {sup 137}Cs concentration of leaf litter varied from non-detected level to above 30 kBq/kg. The {sup 137}Cs concentration of evergreen tree was higher than that of deciduous tree. This may be because deciduous trees were before leafing stage at the time of the accident. However, significant levels of {sup 137}Cs concentration of even deciduous trees suggest that {sup 137}Cs may have been translocated from some part of tree body. On the other hand, deposited {sup 137}Cs still remains on the leaves of evergreen tree. Monthly observation showed that {sup 137}Cs concentration in leaves from C. japonica was slightly decreasing. Further monitoring is needed to predict precisely the amount of {sup 137}Cs deposit onto the forest floor. {sup 137}Cs in soil is still accumulated at the surface. Considerable accumulation and translocation of {sup 137}Cs in tree implies that trees may act as a long-term supplier of radioactive substance to the forest floor, or even a circulator of it between soils. (authors)

  12. Is it better to leave or restore carious deciduous molar teeth? A preliminary study.

    Science.gov (United States)

    Tickle, M; Milsom, K; Kennedy, A

    1999-10-01

    The objective of this study was to compare the extraction and exfoliation experience of filled and unfilled carious deciduous molar teeth. The study was carried out in 1997 in four general dental practices in south Cheshire, UK and involved a longitudinal retrospective review of case notes. A quota sample of 20 case notes of children from each practice was selected according to strict criteria. Subjects had to: Have had experience of approximal caries in one or more of the deciduous molar teeth. Have a date of birth between 1st January 1984 and 31st December 1985. Be a regular attender and in continuous contact with the practice. Data were collected on a common data abstraction form. Variables measured included: Base-line dmft. Site and number of filled teeth. Site and number of unfilled carious teeth. Number of courses of antibiotics. Site and number of pulp therapies. Site, number, method (local or general anaesthetic) of extractions. Reasons for extraction. All teeth not recorded as being extracted were assumed to have exfoliated. In addition, information was collected on the dentists' treatment philosophies. A series of group discussions revealed that the four dentists fitted into two groups according to treatment philosophies; two dentists shared a philosophy of minimal intervention, the other two shared the same views of treating more radically. There was no significant difference between the proportion of filled teeth and the proportion of carious unfilled teeth that were extracted (chi-square 0.05 P = 0.83). A logistic regression showed that for each course of antibiotics administered the odds of having an extraction was multiplied by 5.5 and children who were patients of the interventionist dentists were five times more likely to have an extraction than patients of non-interventionist dentists. Although the study was preliminary in nature no clear benefit could be found in filling deciduous molar teeth against leaving carious teeth unfilled, if avoidance

  13. Meteorological Factors and Tree Characteristics Influencing the Initiation and Rate of Stemflow from Deciduous Trees in an Urban Park

    Science.gov (United States)

    Schooling, J. T.; Carlyle-Moses, D. E.

    2013-12-01

    Stemflow, SF, represents that portion of precipitation that is intercepted by a tree's canopy and diverted to the ground at the tree base by flowing along branches and down the bole. The focused input of water and nutrients associated with SF have been shown to be of hydrological and biogeochemical importance in a number of plant communities and forest environments. Although the concentrated water volume and the nutrient / pollutant fluxes associated with SF in urban areas may be highly relevant for stormwater quantity and quality management, they have received only minor study in built environments. In an urban park in Kamloops, British Columbia, Canada, SF volumes generated from 40 deciduous trees representing 22 species were sampled on a precipitation event basis over a period of 16 months. Using this data, we derived the threshold rainfall depth required for SF initiation from each tree by taking the absolute value of the y-intercept of the linear regression of SF volume versus rainfall depth divided by the slope of that regression. The SF discharge rate once the threshold rainfall depth had been reached was taken as the slope of the linear regression equation. Thus, a simplified SF equation was developed: SFv = QSF x (Pg = Pg''), where SFv is stemflow volume (litres), QSF is the discharge rate (litres / mm), and Pg and Pg' represent the precipitation depth and the threshold precipitation depth, respectively. We then examined the influence of meteorological factors (precipitation type [rain / snow / rain + snow], precipitation depth, rainfall intensity, wind speed and direction, and vapour pressure deficit), and tree characteristics (tree diameter at breast height, tree height, leaf size and orientation, bark roughness, crown projection area, leaf area index, canopy cover fraction, branching angle, the proportion of the crown that was comprised of branches, and overlap with other tree canopies) on QSF and Pg' in order to expand on the simplified model and

  14. CARBON SEQUESTRATION IN PASTURES WITH TREES, TREELESS PASTURES AND DECIDUOUS FOREST FROM HUATUSCO, VERACRUZ

    Directory of Open Access Journals (Sweden)

    José Antonio Torres-Rivera

    2011-11-01

    Full Text Available It was compared the amount of carbon (C sequestered in a pasture with trees (P+Ar and in conventional treeless pastures (P and deciduous forest (BC, typical of the region of Huatusco, Veracruz, Mexico. Total C sequestered by the systems evaluated was 49.9, 63.0 and 469.8 ton ha-1 for P, P+Ar and BC, respectively. The system with the highest amount of C sequestered was BC, with almost equal proportions in the aerial (268.4 ton ha-1 and belowground parts (201.4 ton ha-1. The amount of C sequestered in the livestock systems represented about one tenth of that sequestered in BC, being higher the proportion obtained in P+Ar (13.4 % compared to P (10.6 %. In both livestock systems, a significantly greater amount of C was sequestered in the soil organic matter than in the aerial biomass, with 59.7 and 3.29 ton ha-1 in P+Ar, and with 48.2 and 1.78 ton ha-1 in P, respectively. It is expected that as trees of the P+Ar system gain volume, C sequestration will increase, especially in the aerial biomass.

  15. Altered dynamics of broad-leaved tree species in a Chinese subtropical montane mixed forest: the role of an anomalous extreme 2008 ice storm episode.

    Science.gov (United States)

    Ge, Jielin; Xiong, Gaoming; Wang, Zhixian; Zhang, Mi; Zhao, Changming; Shen, Guozhen; Xu, Wenting; Xie, Zongqiang

    2015-04-01

    Extreme climatic events can trigger gradual or abrupt shifts in forest ecosystems via the reduction or elimination of foundation species. However, the impacts of these events on foundation species' demography and forest dynamics remain poorly understood. Here we quantified dynamics for both evergreen and deciduous broad-leaved species groups, utilizing a monitoring permanent plot in a subtropical montane mixed forest in central China from 2001 to 2010 with particular relevance to the anomalous 2008 ice storm episode. We found that both species groups showed limited floristic alterations over the study period. For each species group, size distribution of dead individuals approximated a roughly irregular and flat shape prior to the ice storm and resembled an inverse J-shaped distribution after the ice storm. Furthermore, patterns of mortality and recruitment displayed disequilibrium behaviors with mortality exceeding recruitment for both species groups following the ice storm. Deciduous broad-leaved species group accelerated overall diameter growth, but the ice storm reduced evergreen small-sized diameter growth. We concluded that evergreen broad-leaved species were more susceptible to ice storms than deciduous broad-leaved species, and ice storm events, which may become more frequent with climate change, might potentially threaten the perpetuity of evergreen-dominated broad-leaved forests in this subtropical region in the long term. These results underscore the importance of long-term monitoring that is indispensible to elucidate causal links between forest dynamics and climatic perturbations.

  16. Tree growth response to climate change at the deciduous-boreal forest ecotone, Ontario, Canada

    Energy Technology Data Exchange (ETDEWEB)

    Goldblum, D. [Wisconsin-Whitewater Univ., Whitewater, WI (United States). Dept. of Geography and Geology; Rigg, L.S. [Northern Illinois Univ., DeKalb, IL (United States). Dept. of Geography

    2005-11-01

    Recent interest in the impact that future climate change may have on forest communities can be attributed to the fact that migration of tree species has been slow with respect to past climate changes and also because of the high degree of habitat fragmentation that has occurred in the recent past. For that reason, this study examined the implications of climate change on the future of sugar maple, white spruce and balsam fir. These trees represent the 3 dominant forest species at the deciduous-boreal forest ecotone in Ontario, Canada. The analysis was based on the responses of individual species to past monthly temperature and precipitation conditions as well as simulated monthly temperature and precipitation conditions in the study area for the 2080s. The sensitivity of the tree species to past climate with predicted conditions for the 2080 period was also considered. In particular, tree-ring analysis was used to compare local species-specific growth responses with instrumental climate records since 1900 to determine which climate variables control growth rates of these 3 species. Present temperature and precipitation averages were compared with general circulation model (GCM) predictions of monthly temperature and monthly precipitation to evaluate the potential benefit or harm to the dominant tree species over the next 80 years. It was concluded that sugar maple may persist in the medium term up to several centuries, as existing trees pass through their natural life-span without reproductive replacement. However, with extreme climate change, over many centuries, even the sugar maple at this northern range limit might be in jeopardy. White spruce is likely to benefit less, and the dominant balsam fir is likely to experience a decrease in growth potential. These projected changes would enhance the future status of sugar maple at its northern limit and facilitate range expansion northward in response to global warming. Although the study concerns only a small area

  17. Genetic transformation of deciduous fruit trees conferring resistance against diseases

    International Nuclear Information System (INIS)

    Mansvelt, E.L.; Glyn-Woods, T.; Watts, L.; Rabie, A.; Appel, M.; Bellstedt, D.U.

    1998-01-01

    Long breeding cycles make cultivar development a lengthy process in deciduous fruit species. Gene transfer is, accordingly, a goal with significant commercial value. In many plant species, especially in woody plants, a prerequisite for genetic engineering is the ability to regenerate plants from transformed cells. Development of single cell regeneration is the first step towards exploration of gene transfer techniques. In this investigation media for plum and apple leaf disk regeneration were developed. Transformation experiments were performed. The vector EHA105 containing the gus-intron gene was found to be effective for gene transfer. Induction of the virG genes with aceto-syringone did not enhance transformation. Cefotaxime that was supplemented in the plum selection medium to suppress the Agrobacterium vector seriously inhibited leaf disk regeneration. However, in applies it was not detrimental. With further apple transformation experiments, factors such as preculturing, age of leaves, sucrose and cefotaxime concentrations did not increase the transformation efficiency of the marker gene. The harpin protein, essential for the pathogenicity of Pseudomonas syringae pv. syringae which incites bacterial canker of stone fruit, ws amplified and cloned into an expression vector. The fusion protein was purified. This will be used in future studies to elucidate the host-pathogen interaction, and to identify antibacterial genes. (author)

  18. Vitex altissima L.f of verbenaceae is a large tree of dry deciduous ...

    Indian Academy of Sciences (India)

    spreading crown and greyish brown scaly bark (tree in the picture is a young specimen). Leaves are compound with three or five leaflets. Flowers are numerous on branched inflorescence, small and white, tinged with blue. Corolla is two-lipped and stamens 4. Fruits are small (0.8 cm) and purplish black when ripe. Timber of ...

  19. Maintenance of carbohydrate transport in tall trees

    DEFF Research Database (Denmark)

    Savage, Jessica A.; Beecher, Sierra D.; Clerx, Laura

    2017-01-01

    Trees present a critical challenge to long-distance transport because as a tree grows in height and the transport pathway increases in length, the hydraulic resistance of the vascular tissue should increase. This has led many to question whether trees can rely on a passive transport mechanism to ...... that reduce transport resistance. As a result, the key to the long-standing mystery of how trees maintain phloem transport as they increase in size lies in the structure of the phloem and its ability to change hydraulic properties with plant height.......Trees present a critical challenge to long-distance transport because as a tree grows in height and the transport pathway increases in length, the hydraulic resistance of the vascular tissue should increase. This has led many to question whether trees can rely on a passive transport mechanism...... in the leaves of a tall tree in situ. Across nine deciduous species, we find that hydraulic resistance in the phloem scales inversely with plant height because of a shift in sieve element structure along the length of individual trees. This scaling relationship seems robust across multiple species despite large...

  20. Understanding Seasonal Dynamics of the Photo-Protective Xanthophyll Cycle Improves Remote Detection of Photosynthetic Phenology in Deciduous Trees and Evergreen Conifers

    Science.gov (United States)

    Ensminger, I.; Wong, C. Y.; Junker, L. V.; Bathena, Y.; Arain, M. A.; D'Odorico, P.

    2017-12-01

    The ability of plants to sequester carbon is highly variable over the course of the year and reflects seasonal variation in photosynthetic efficiency. This seasonal variation is most prominent during autumn, when leaves of deciduous tree species undergo senescence, which is associated with the downregulation of photosynthesis and a change of leaf color and leaf optical properties. Vegetation indices derived from remote sensing of leaf optical properties using e.g. spectral reflectance measurements are increasingly used to monitor and predict growing season length and seasonal variation in carbon sequestration. Here we compare leaf-level, canopy-level and drone based observations of leaf spectral reflectance measurements. We demonstrate that some of the widely used vegetation indices such as the normalized difference vegetation index (NDVI) and photochemical reflectance index (PRI) vary in their ability to adequately track the seasonal variation in photosynthetic efficiency and chlorophyll content. We further show that monitoring seasonal variation of photosynthesis using NDVI or PRI is particularly challenging in evergreen conifers, due to little seasonal variation in foliage. However, there is remarkable seasonal variation in leaf optical properties associated with changes in pools of xanthophyll cycle pigments and carotenoids that provide a promising way of monitoring photosynthetic phenology in evergreen conifers via leaf reflectance measurements.

  1. Host tree phenology affects vascular epiphytes at the physiological, demographic and community level

    Science.gov (United States)

    Einzmann, Helena J. R.; Beyschlag, Joachim; Hofhansl, Florian; Wanek, Wolfgang; Zotz, Gerhard

    2015-01-01

    The processes that govern diverse tropical plant communities have rarely been studied in life forms other than trees. Structurally dependent vascular epiphytes, a major part of tropical biodiversity, grow in a three-dimensional matrix defined by their hosts, but trees differ in their architecture, bark structure/chemistry and leaf phenology. We hypothesized that the resulting seasonal differences in microclimatic conditions in evergreen vs. deciduous trees would affect epiphytes at different levels, from organ physiology to community structure. We studied the influence of tree leaf phenology on vascular epiphytes on the Island of Barro Colorado, Panama. Five tree species were selected, which were deciduous, semi-deciduous or evergreen. The crowns of drought-deciduous trees, characterized by sunnier and drier microclimates, hosted fewer individuals and less diverse epiphyte assemblages. Differences were also observed at a functional level, e.g. epiphyte assemblages in deciduous trees had larger proportions of Crassulacean acid metabolism species and individuals. At the population level a drier microclimate was associated with lower individual growth and survival in a xerophytic fern. Some species also showed, as expected, lower specific leaf area and higher δ13C values when growing in deciduous trees compared with evergreen trees. As hypothesized, host tree leaf phenology influences vascular epiphytes at different levels. Our results suggest a cascading effect of tree composition and associated differences in tree phenology on the diversity and functioning of epiphyte communities in tropical lowland forests. PMID:25392188

  2. Flowering Trees

    Indian Academy of Sciences (India)

    Flowering Trees. Boswellia serrata Roxb. ex Colebr. (Indian Frankincense tree) of Burseraceae is a large-sized deciduous tree that is native to India. Bark is thin, greenish-ash-coloured that exfoliates into smooth papery flakes. Stem exudes pinkish resin ... Fruit is a three-valved capsule. A green gum-resin exudes from the ...

  3. Tree Classification with Fused Mobile Laser Scanning and Hyperspectral Data

    Science.gov (United States)

    Puttonen, Eetu; Jaakkola, Anttoni; Litkey, Paula; Hyyppä, Juha

    2011-01-01

    Mobile Laser Scanning data were collected simultaneously with hyperspectral data using the Finnish Geodetic Institute Sensei system. The data were tested for tree species classification. The test area was an urban garden in the City of Espoo, Finland. Point clouds representing 168 individual tree specimens of 23 tree species were determined manually. The classification of the trees was done using first only the spatial data from point clouds, then with only the spectral data obtained with a spectrometer, and finally with the combined spatial and hyperspectral data from both sensors. Two classification tests were performed: the separation of coniferous and deciduous trees, and the identification of individual tree species. All determined tree specimens were used in distinguishing coniferous and deciduous trees. A subset of 133 trees and 10 tree species was used in the tree species classification. The best classification results for the fused data were 95.8% for the separation of the coniferous and deciduous classes. The best overall tree species classification succeeded with 83.5% accuracy for the best tested fused data feature combination. The respective results for paired structural features derived from the laser point cloud were 90.5% for the separation of the coniferous and deciduous classes and 65.4% for the species classification. Classification accuracies with paired hyperspectral reflectance value data were 90.5% for the separation of coniferous and deciduous classes and 62.4% for different species. The results are among the first of their kind and they show that mobile collected fused data outperformed single-sensor data in both classification tests and by a significant margin. PMID:22163894

  4. Estimation of Heavy Metals in Neem Tree Leaves along Katsina ...

    African Journals Online (AJOL)

    Widespread and growing use of medicinal plants has created public health challenges in terms of quality, safety and effectiveness. Using Atomic Absorption Spectrophotometer (AAS), concentrations of Ni, Zn, Mn, Cu, Cr and Pb, , were determined in samples of neem tree (Azadirachta indica) leaves obtained from Katsina, ...

  5. Comparison of leaf beetle assemblages of deciduous trees canopies in Hungary (Coleoptera: Chrysomelidae).

    Science.gov (United States)

    Vig, K; Markó, V

    2005-01-01

    The species richness and species composition of Coleoptera assemblages were investigated in deciduous tree canopies in Hungary. Apple and pear orchards were investigated in Nagykovácsi, Kecskemét and Sárospatak in 1990-94, and limes and maples in Keszthely in 1999-2002. Faunistic results and conclusions of these investigations were published elsewhere. Examination of the fauna of parks, avenues and other planted urban plant stocks has only begun to occupy researchers in the last decade in Hungary. The proportion of leaf-beetle species in the material gathered on maples and limes ranged between 17.0 and 21.3 per cent. The commonest leaf-beetle specimens collected in the lime canopy were Aphthona euphorbiae, Chaetocnema tibialis, Longitarsus lycopi, L. pellucidus, L. pratensis and L. succineus. The commonest on maple were Aphthona euphorbiae, Chaetocnema concinna, C. tibialis, Longitarsus lycopi, L. pellucidus, L. succineus, Phyllotreta cruciferae and P. vittula. This study presents the details on the composition of the chrysomelid communities that was compared by metric ordination using the Syntax 5.1 program.

  6. Branch Wood Decomposition of Tree Species in a Deciduous Temperate Forest in Korea

    Directory of Open Access Journals (Sweden)

    Sangsub Cha

    2017-05-01

    Full Text Available Woody debris, which is supplied by branch litter, is an important component of forest ecosystems as it contains large quantities of organic matter and nutrients. We evaluated changes in branch wood dry weight and nutrient content of six common species (Fraxinus rhynchophylla, Pinus densiflora, Prunus sargentii, Quercus mongolica, Acer pseudosieboldianum, and Symplocos chinensis for. pilosa in a deciduous temperate forest in Korea for 40 months. Branch wood disk samples 1.4–1.6 cm thick were cut, and mass loss was measured over time using the litterbag method. No significant differences in mass loss were recorded among the six tree species. Further, mass loss was negatively correlated with initial lignin concentration and positively correlated with both initial cellulose concentration and wood density for each species. Species with high wood cellulose content had high wood density while the lignin content in wood was relatively low. Accordingly, cellulose contributed to wood density, creating a relatively lower lignin content, and the decreased lignin concentration increased the wood decomposition rate.

  7. The C-household of young broad-leaved and conifer tree species exposed to long-term carbon limitation by shading

    Science.gov (United States)

    Weber, Raphael; Hoch, Günter

    2017-04-01

    Non-structural carbohydrates (NSC, i.e. free sugars and starch) are regarded as freely available carbon (C) reserves in plants. They are often quantified to estimate a plant's C-balance, assuming that NSC are controlled by the net-balance between photo-assimilation and C-usage (respiration, growth and other sinks). Within a recent field experiment, we investigated the extent, to which C-reserves (NSC) can be formed in young trees against prevailing C-sink demands (growth) under C-limitation. A total of almost 1000 individuals of two-year-old tree saplings from 6 deciduous, broadleaved species and 4 evergreen conifer species were planted on a field side. Half of the trees per species were treated with long-term C-limitation by exposing them to continuous deep shade conditions (5% of natural PPFD) under a permanent shading tent. C gas-exchange, growth and NSC tissue concentrations were analyzed in shaded and unshaded saplings for two consecutive years. Three months after the beginning of the experiment, leaf photosynthesis acclimatized to the low light conditions, with leaves of shaded trees showing significantly higher SLA and lower light saturation and maximum photosynthesis. During the second season of the experiment, most species exhibited very strong reductions in NSC, but much less pronounced reductions in growth. In contrast, other species, with few exceptions, kept NSC concentrations similar to unshaded controls, while growth virtually stopped under deep shade. In conclusion, we found species-specific strategies in the trees' C-household after two years of C-limitation, that fall into two major carbon allocation strategies: 1) "C-spenders", which deplete C reserves in order to keep up significant growth, and 2) "C-savers", which reduce C sink activities to a minimum in order to store substantial amounts of C reserves. Overall, early-successional species tended to follow the first strategy, while late-successional species tended to save higher C reserve pools

  8. Transcriptional signatures in leaves of adult European beech trees (Fagus sylvatica L.) in an experimentally enhanced free air ozone setting

    Energy Technology Data Exchange (ETDEWEB)

    Olbrich, Maren, E-mail: maren.olbrich@helmholtz-muenchen.d [Institute of Biochemical Plant Pathology, Helmholtz Zentrum Muenchen - German Research Center for Environmental Health, 85764 Neuherberg (Germany); Gerstner, Elke; Bahnweg, Guenther [Institute of Biochemical Plant Pathology, Helmholtz Zentrum Muenchen - German Research Center for Environmental Health, 85764 Neuherberg (Germany); Haeberle, Karl-Heinz; Matyssek, Rainer [Technische Universitaet Muenchen, Ecophysiology of Plants, Am Hochanger 13, 85354 Freising (Germany); Welzl, Gerhard [Institute of Developmental Genetics, Helmholtz Zentrum Muenchen - German Research Center for Environmental Health, 85764 Neuherberg (Germany); Heller, Werner; Ernst, Dieter [Institute of Biochemical Plant Pathology, Helmholtz Zentrum Muenchen - German Research Center for Environmental Health, 85764 Neuherberg (Germany)

    2010-04-15

    Tropospheric ozone causes severe oxidative stress in plants. To investigate the transcriptional responsiveness of adult trees to ozone, fully-expanded sun and shade leaves of mature beech trees were harvested at four time points over the entire vegetation period in 2005 and 2006. Microarray analyses were conducted on leaves from trees grown in the field under ambient and twice-ambient ozone concentrations at Kranzberger Forst (Bavaria). Beech trees changed their transcript levels in response to ozone. In the years 2005 and 2006 different transcription patterns were observed; this may have been a result of different weather conditions and ozone uptake. Furthermore, we obtained differences in mRNA expression patterns between shade and sun leaves. In the ozone-treated sun leaves of 2005, slightly up- and down-regulated transcript levels were detected, particularly in the spring and autumn, whereas shade leaves clearly exhibited reduced mRNA levels, particularly at the end of the vegetation period. In 2006, this pattern could not be confirmed, and in the autumn, four other transcripts were slightly up-regulated in ozone-treated shade leaves. In addition, two other transcripts were found to be influenced in sun leaves in the spring/summer. While we detected changes in the levels of only a few transcripts, the observed effects were not identical in both years. In conclusion, elevated ozone exhibited very small influence on the transcription levels of genes of mature beech trees. - At the transcriptional level, leaves of mature beech trees barely react to double ambient ozone concentrations; differences are detected primarily between sun/shade leaves and between different growing seasons.

  9. Transcriptional signatures in leaves of adult European beech trees (Fagus sylvatica L.) in an experimentally enhanced free air ozone setting

    International Nuclear Information System (INIS)

    Olbrich, Maren; Gerstner, Elke; Bahnweg, Guenther; Haeberle, Karl-Heinz; Matyssek, Rainer; Welzl, Gerhard; Heller, Werner; Ernst, Dieter

    2010-01-01

    Tropospheric ozone causes severe oxidative stress in plants. To investigate the transcriptional responsiveness of adult trees to ozone, fully-expanded sun and shade leaves of mature beech trees were harvested at four time points over the entire vegetation period in 2005 and 2006. Microarray analyses were conducted on leaves from trees grown in the field under ambient and twice-ambient ozone concentrations at Kranzberger Forst (Bavaria). Beech trees changed their transcript levels in response to ozone. In the years 2005 and 2006 different transcription patterns were observed; this may have been a result of different weather conditions and ozone uptake. Furthermore, we obtained differences in mRNA expression patterns between shade and sun leaves. In the ozone-treated sun leaves of 2005, slightly up- and down-regulated transcript levels were detected, particularly in the spring and autumn, whereas shade leaves clearly exhibited reduced mRNA levels, particularly at the end of the vegetation period. In 2006, this pattern could not be confirmed, and in the autumn, four other transcripts were slightly up-regulated in ozone-treated shade leaves. In addition, two other transcripts were found to be influenced in sun leaves in the spring/summer. While we detected changes in the levels of only a few transcripts, the observed effects were not identical in both years. In conclusion, elevated ozone exhibited very small influence on the transcription levels of genes of mature beech trees. - At the transcriptional level, leaves of mature beech trees barely react to double ambient ozone concentrations; differences are detected primarily between sun/shade leaves and between different growing seasons.

  10. [Conservative treatment of deciduous teeth--a review].

    Science.gov (United States)

    Magnusson, B

    1976-06-01

    In all countries with a lack of manpower in dentistry, there is an unfortunate tendency to leave the primary teeth without proper conservative treatment. In addition to toothaches and poor esthetics, a neglected care of the primary dentition may result in several other untoward effects. Decayed deciduous teeth may cause such a discomfort during tooth-brushing that the child is prevented from learning good oral hygiene habits. With bad primary molars the child cannot chew properly, and may have to choose soft and often cariogenic food. When the permanent teeth erupt among the decayed deciduous teeth, there will be a greater chance for them to have carious attacks as well. Premature loss of primary molars may lead to malocclusion. It must also be kept in mind that the treatment of badly decayed teeth, including necessary extractions, may be difficult. This may cause fear of dental treatment. On the basis of current Swedish philosophies of treatment the author surveys various conservative procedures for deciduous teeth-amalgam therapy, stainless steel crowns, composites and disking.

  11. Analysis of bleeding saps and radioactive measurements of deciduous trees

    International Nuclear Information System (INIS)

    Gomernik-Besser, E.

    1993-07-01

    Samples of bleeding sap of Betula pendula Roth, Betula lutea L., Betula papyrifera L., Betula mandshuria L., Salix melichoferi Saut., Cornus florida L., Evodea velutina L., Vitis amurensis L., Acer tartaricum L., Aesculus parviflora L., and Juglans regia L. in the botanical garden in Graz have been collected during springs of 1987, 1988, and 1989. After a special treatment (ion-exchange and freeze-drying) the bleeding saps have been searched for the compounds of sugars, amino acids and organic acids by gaschromatrography. LAMMA-spectra showed the ion composition, and radioactivity measurements on leaves of the trees have also been made. In all bleeding saps sugars could be identified in various concentrations, mainly glucose and fructose. All trees showed nearly the same acid spectrum, and the most common ingredient was malic acid. In the bleeding saps of the Betulaceae and Juglans regia the major constituent was citrulline. In Acer tartaricum allantoine was present in large concentration. In Evodea velutina, Aesculus parviflora, Vitis amurensis and Cornus florida glutamin could be identified in large concentration. After the reactor accident of Tschernobyl in April 1986 the number of synthetic radionuclides increased and they could be identified. The LAMMA-spectra showed high contents of potassium and calcium in the bleeding saps. (author)

  12. Analysis of bleeding saps and radioactive measurements of deciduous trees

    International Nuclear Information System (INIS)

    Gomernik-Besser, E.

    1993-07-01

    Samples of bleeding sap of Betula pendula Roth, Betula lutea L., Betula papyrifera L., Betula mandshuria L., Salix mielichoferi Saut., Cornus florida L., Evodea velutina L., Vitis amurensis L., Acer tartaricum L., Aesculus parviflora L., and Juglans regia L. in the botanical garden in Graz have been collected during springs of 1987, 1988, and 1989. After a special treatment (ion-exchange and freeze-drying) the bleeding saps have been searched for the compounds of sugars, amino acids and organic acids by gas-chromatrography. LAMMA-spectra showed the ion composition, and radioactivity measurements on leaves of the trees have also been made. In all bleeding saps sugars could be identified in various concentrations, mainly glucose and fructose. All trees showed nearly the same acid spectrum, and the most common ingredient was malic acid. In the bleeding saps of the Betulaceae and Juglans regia the major constituent was citrulline. In Acer tartaricum allantoine was present in large concentration. In Evodea velutina, Aesculus parviflora, Vitis amurensis and Cornus florida glutamin could be identified in large concentration. After the reactor accident of Tschernobyl in April 1986 the number of synthetic radionuclides increased and they could be identified. The LAMMA-spectra showed high contents of kalium and calcium in the bleeding saps. (author)

  13. Chlorophyll Catabolites in Senescent Leaves of the Plum Tree (Prunus domestica).

    Science.gov (United States)

    Erhart, Theresia; Mittelberger, Cecilia; Vergeiner, Clemens; Scherzer, Gerhard; Holzner, Barbara; Robatscher, Peter; Oberhuber, Michael; Kräutler, Bernhard

    2016-11-01

    In cold extracts of senescent leaves of the plum tree (Prunus domestica ssp. domestica), six colorless non-fluorescent chlorophyll catabolites (NCCs) were characterized, named Pd-NCCs. In addition, several minor NCC fractions were tentatively classified. The structure of the most polar one of the NCCs, named Pd-NCC-32, featured an unprecedented twofold glycosidation pattern. Three of the NCCs are also functionalized at their 3 2 -position by a glucopyranosyl group. In addition, two of these glycosidated NCCs carry a dihydroxyethyl group at their 18-position. In the polar Pd-NCC-32, the latter group is further glycosidated at the terminal 18 2 -position. Four other major Pd-NCCs and one minor Pd-NCC were identified with five NCCs from higher plants known to belong to the 'epi'-series. In addition, tentative structures were derived for two minor fractions, classified as yellow chlorophyll catabolites, which represented (formal) oxidation products of two of the observed Pd-NCCs. The chlorophyll catabolites in leaves of plum feature the same basic structural pattern as those found in leaves of apple and pear trees. © 2016 The Authors. Chemistry & Biodiversity Published by Wiley-VHCA AG, Zurich, Switzerland.

  14. Is deciduousness a key to climate resilience among iconic California savanna oak species? Relating phenological habits to seasonal indicators of tree physiological and water stress across field, hyperspectral, drone (UAS)-based multispectral and thermal image data

    Science.gov (United States)

    Mayes, M. T.; Caylor, K. K.; Ehlmann, B. L.; Greenberger, R. N.; Estes, L. D.

    2017-12-01

    In California (CA) savannas, oak trees (genus Quercus) play keystone roles in water and nutrient cycling, support biodiversity and many land-use activities. Declines in oak basal area of up to 25% from the 1930s-2000s, which have occurred alongside climate trends such as increasing variability of rainfall and prevalence of hotter droughts, threaten the services and ecological functions these trees provide. It is particularly unclear how climate relates to productivity and stress across oak species. Past work has found that seedling recruitment has varied inversely with "deciduousness." That is, evergreen oaks (e.g. Quercus agrifola. Coast Live Oak) are reproducing more successfully than drought-deciduous (e.g. Quercus douglassi, Blue Oak), which in turn are more successful than fully deciduous species (e.g. Quercus lobata, Valley Oak). However, there is poor understanding of how these ecological trends by species, corresponding with phenological habit, relate to physiological and ecohydrological processes such as carbon assimilation, water or nutrient use efficiency in mature tree stands. This limits predictive capability for which species will be most resilient to harsher future growing conditions, and, how to monitor stress and productivity in long-lived mature oak communities across landscapes via tools including remotely sensed data. This project explores how ecophysiological variables (e.g. stomatal conductance) relate to phenological habits across three oak species (Coast Live, Blue and Valley) over a seasonal dry-down period in Santa Barbara County, CA. Our goal is to probe if deciduousness is a key to resilience in productivity and water stress across iconic oak species. We test relationships between leaf and canopy-level field data, and indicators from multiple new sources of remotely sensed data, including ground hyperspectral, drone (UAS)-based multi-spectral and thermal image data, as means of monitoring tree physiological and water stress from scales

  15. Quantitative and qualitative characteristics of cell wall components and prenyl lipids in the leaves of Tilia x euchlora trees growing under salt stress.

    Science.gov (United States)

    Milewska-Hendel, Anna; Baczewska, Aneta H; Sala, Katarzyna; Dmuchowski, Wojciech; Brągoszewska, Paulina; Gozdowski, Dariusz; Jozwiak, Adam; Chojnacki, Tadeusz; Swiezewska, Ewa; Kurczynska, Ewa

    2017-01-01

    The study was focused on assessing the presence of arabinogalactan proteins (AGPs) and pectins within the cell walls as well as prenyl lipids, sodium and chlorine content in leaves of Tilia x euchlora trees. The leaves that were analyzed were collected from trees with and without signs of damage that were all growing in the same salt stress conditions. The reason for undertaking these investigations was the observations over many years that indicated that there are trees that present a healthy appearance and trees that have visible symptoms of decay in the same habitat. Leaf samples were collected from trees growing in the median strip between roadways that have been intensively salted during the winter season for many years. The sodium content was determined using atomic spectrophotometry, chloride using potentiometric titration and poly-isoprenoids using HPLC/UV. AGPs and pectins were determined using immunohistochemistry methods. The immunohistochemical analysis showed that rhamnogalacturonans I (RG-I) and homogalacturonans were differentially distributed in leaves from healthy trees in contrast to leaves from injured trees. In the case of AGPs, the most visible difference was the presence of the JIM16 epitope. Chemical analyses of sodium and chloride showed that in the leaves from injured trees, the level of these ions was higher than in the leaves from healthy trees. Based on chromatographic analysis, four poly-isoprenoid alcohols were identified in the leaves of T. x euchlora. The levels of these lipids were higher in the leaves from healthy trees. The results suggest that the differences that were detected in the apoplast and symplasm may be part of the defensive strategy of T. x euchlora trees to salt stress, which rely on changes in the chemical composition of the cell wall with respect to the pectic and AGP epitopes and an increased synthesis of prenyl lipids.

  16. Assessment of heavy metal concentration in soil and leaves of tree ...

    African Journals Online (AJOL)

    The gaseous emissions from scrap metal recycling factory could cause pollution to the environment if the concentrations are substantial and not properly controlled. This study determined the concentration of some heavy metals (Iron, Copper, Lead and Cadmium) in the leaves of selected tree species and soils around the ...

  17. Stem water storage in five coexisting temperate broad-leaved tree species: significance, temporal dynamics and dependence on tree functional traits.

    Science.gov (United States)

    Köcher, Paul; Horna, Viviana; Leuschner, Christoph

    2013-08-01

    The functional role of internal water storage is increasingly well understood in tropical trees and conifers, while temperate broad-leaved trees have only rarely been studied. We examined the magnitude and dynamics of the use of stem water reserves for transpiration in five coexisting temperate broad-leaved trees with largely different morphology and physiology (genera Fagus, Fraxinus, Tilia, Carpinus and Acer). We expected that differences in water storage patterns would mostly reflect species differences in wood anatomy (ring vs. diffuse-porous) and wood density. Sap flux density was recorded synchronously at five positions along the root-to-branch flow path of mature trees (roots, three stem positions and branches) with high temporal resolution (2 min) and related to stem radius changes recorded with electronic point dendrometers. The daily amount of stored stem water withdrawn for transpiration was estimated by comparing the integrated flow at stem base and stem top. The temporal coincidence of flows at different positions and apparent time lags were examined by cross-correlation analysis. Our results confirm that internal water stores play an important role in the four diffuse-porous species with estimated 5-12 kg day(-1) being withdrawn on average in 25-28 m tall trees representing 10-22% of daily transpiration; in contrast, only 0.5-2.0 kg day(-1) was withdrawn in ring-porous Fraxinus. Wood density had a large influence on storage; sapwood area (diffuse- vs. ring-porous) may be another influential factor but its effect was not significant. Across the five species, the length of the time lag in flow at stem top and stem base was positively related to the size of stem storage. The stem stores were mostly exhausted when the soil matrix potential dropped below -0.1 MPa and daily mean vapor pressure deficit exceeded 3-5 hPa. We conclude that stem storage is an important factor improving the water balance of diffuse-porous temperate broad-leaved trees in moist

  18. Optical solar energy adaptations and radiative temperature control of green leaves and tree barks

    Energy Technology Data Exchange (ETDEWEB)

    Henrion, Wolfgang; Tributsch, Helmut [Department of Si-Photovoltaik and Solare Energetik, Hahn-Meitner-Institut Berlin, 14109 Berlin (Germany)

    2009-01-15

    Trees have adapted to keep leaves and barks cool in sunshine and can serve as interesting bionic model systems for radiative cooling. Silicon solar cells, on the other hand, loose up to one third of their energy efficiency due to heating in intensive sunshine. It is shown that green leaves minimize absorption of useful radiation and allow efficient infrared thermal emission. Since elevated temperatures are detrimental for tensile water flow in the Xylem tissue below barks, the optical properties of barks should also have evolved so as to avoid excessive heating. This was tested by performing optical studies with tree bark samples from representative trees. It was found that tree barks have optimized their reflection of incoming sunlight between 0.7 and 2 {mu}m. This is approximately the optical window in which solar light is transmitted and reflected by green vegetation. Simultaneously, the tree bark is highly absorbing and thus radiation emitting between 6 and 10 {mu}m. These two properties, mainly provided by tannins, create optimal conditions for radiative temperature control. In addition, tannins seem to have adopted a function as mediators for excitation energy towards photo-antioxidative activity for control of radiation damage. The results obtained are used to discuss challenges for future solar cell optimization. (author)

  19. Atmospheric Direct Uptake and Long-term Fate of Radiocesium in Trees after the Fukushima Nuclear Accident

    Science.gov (United States)

    Mahara, Yasunori; Ohta, Tomoko; Ogawa, Hideki; Kumata, Atsushi

    2014-11-01

    Large areas of forests were radioactively contaminated by the Fukushima nuclear accident of 2011, and forest decontamination is now an important problem in Japan. However, whether trees absorb radioactive fallout from soil via the roots or directly from the atmosphere through the bark and leaves is unclear. We measured the uptake of radiocesium by trees in forests heavily contaminated by the Fukushima nuclear accident. The radiocesium concentrations in sapwood of two tree species, the deciduous broadleaved konara (Quercus serrata) and the evergreen coniferous sugi (Cryptomeria japonica), were higher than that in heartwood. The concentration profiles showed anomalous directionality in konara and non-directionality in sugi, indicating that most radiocesium in the tree rings was directly absorbed from the atmosphere via bark and leaves rather than via roots. Numerical modelling shows that the maximum 137Cs concentration in the xylem of konara will be achieved 28 years after the accident. Conversely, the values for sugi will monotonously decrease because of the small transfer factor in this species. Overall, xylem 137Cs concentrations will not be affected by root uptake if active root systems occur 10 cm below the soil.

  20. Priming effects on seed germination in Tecoma stans (Bignoniaceae) and Cordia megalantha (Boraginaceae), two tropical deciduous tree species

    Science.gov (United States)

    Alvarado-López, Sandra; Soriano, Diana; Velázquez, Noé; Orozco-Segovia, Alma; Gamboa-deBuen, Alicia

    2014-11-01

    Successful revegetation necessarily requires the establishment of a vegetation cover and one of the challenges for this is the scarce knowledge about germination and seedling establishment of wild tree species. Priming treatments (seed hydration during a specific time followed by seed dehydration) could be an alternative germination pre-treatment to improve plant establishment. Natural priming (via seed burial) promotes rapid and synchronous germination as well as the mobilisation of storage reserves; consequently, it increases seedling vigour. These metabolic and physiological responses are similar to those occurring as a result of the laboratory seed priming treatments (osmopriming and matrix priming) applied successfully to agricultural species. In order to know if natural priming had a positive effect on germination of tropical species we tested the effects of natural priming on imbibition kinetics, germination parameters (mean germination time, lag time and germination rate and percentage) and reserve mobilisation in the seeds of two tree species from a tropical deciduous forest in south-eastern México: Tecoma stans (L Juss. Ex Kunth) and Cordia megalantha (S.F Blake). The wood of both trees are useful for furniture and T. stans is a pioneer tree that promotes soil retention in disturbed areas. We also compared the effect of natural priming with that of laboratory matrix priming (both in soil). Matrix priming improved germination of both studied species. Natural priming promoted the mobilisation of proteins and increased the amount of free amino acids and of lipid degradation in T. stans but not in C. megalantha. Our results suggest that the application of priming via the burial of seeds is an easy and inexpensive technique that can improve seed germination and seedling establishment of tropical trees with potential use in reforestation and restoration practices.

  1. An observation-based progression modeling approach to spring and autumn deciduous tree phenology

    Science.gov (United States)

    Yu, Rong; Schwartz, Mark D.; Donnelly, Alison; Liang, Liang

    2016-03-01

    It is important to accurately determine the response of spring and autumn phenology to climate change in forest ecosystems, as phenological variations affect carbon balance, forest productivity, and biodiversity. We observed phenology intensively throughout spring and autumn in a temperate deciduous woodlot at Milwaukee, WI, USA, during 2007-2012. Twenty-four phenophase levels in spring and eight in autumn were recorded for 106 trees, including white ash, basswood, white oak, boxelder, red oak, and hophornbeam. Our phenological progression models revealed that accumulated degree-days and day length explained 87.9-93.4 % of the variation in spring canopy development and 75.8-89.1 % of the variation in autumn senescence. In addition, the timing of community-level spring and autumn phenophases and the length of the growing season from 1871 to 2012 were reconstructed with the models developed. All simulated spring phenophases significantly advanced at a rate from 0.24 to 0.48 days/decade ( p ≤ 0.001) during the 1871-2012 period and from 1.58 to 2.00 days/decade ( p coloration) and 0.50 (full-leaf coloration) days/decade ( p coloration and leaf fall, and suggested accelerating simulated ecosystem responses to climate warming over the last four decades in comparison to the past 142 years.

  2. Environmental variables and tree population structures in deciduous forests of central Brazil with different levels of logging

    Directory of Open Access Journals (Sweden)

    Daniel Luis Mascia Vieira

    2008-04-01

    Full Text Available Population structures of six tree species in three fragments of intact seasonal deciduous forest and three fragments disturbed by logging were studied in the northeastern Goiás. Forty random 400 m² plots were allocated in each fragment to survey plant population structures, number of stumps, cattle feces, burnt logs, and canopy openness. Soil cover by life forms was estimated in 1m² sub-plots. Lianas were abundant in intermediately logged fragments and invasive herbs in the most disturbed fragment. Cattle avoided dense herbaceous strata, such as liana tangles. Cavanillesia arborea, Eugenia dysenterica and Swartzia multijuga trees occurred at very low densities in all the fragments and their seedlings were practically absent, which might endanger their future populations in these fragments. Myracrodruon urundeuva, Tabebuia impetiginosa and Astronium fraxinifolium, the most logged species, had high density of seedlings in all the fragments. However, the highest density of saplings and juvenile individuals occurred in the most disturbed fragment.As estruturas populacionais de seis espécies de árvores foram estudadas em três fragmentos de floresta estacional decidual intactos e três fragmentos impactados pela exploração seletiva de madeira no nordeste goiano. Quarenta parcelas de 400m² foram estabelecidas em cada fragmento para a amostragem de populações, número de tocos, fezes de gado, troncos queimados e abertura de dossel. A cobertura do solo por formas de vida foi estimada em sub-parcelas de 1m². Lianas foram mais abundantes em fragmentos com perturbação intermediária, enquanto herbáceas invasoras no fragmento mais perturbado. Cavanillesia arborea, Eugenia dysenterica e Swartzia multijuga ocorreram em densidades muito baixas em todos os fragmentos e plântulas foram praticamente ausentes, o que pode ameaçar o futuro de suas populações. Myracrodruon urundeuva, Tabebuia impetiginosa e Astronium fraxinifolium, as espécies mais

  3. The effect of interspecific variation in photosynthetic plasticity on 4-year growth rate and 8-year survival of understorey tree seedlings in response to gap formations in a cool-temperate deciduous forest.

    Science.gov (United States)

    Oguchi, Riichi; Hiura, Tsutom; Hikosaka, Kouki

    2017-08-01

    Gap formation increases the light intensity in the forest understorey. The growth responses of seedlings to the increase in light availability show interspecific variation, which is considered to promote biodiversity in forests. At the leaf level, some species increase their photosynthetic capacity in response to gap formation, whereas others do not. Here we address the question of whether the interspecific difference in the photosynthetic response results in the interspecific variation in the growth response. If so, the interspecific difference in photosynthetic response would also contribute to species coexistence in forests. We also address the further relevant question of why some species do not increase their photosynthetic capacity. We assumed that some cost of photosynthetic plasticity may constrain acquisition of the plasticity in some species, and hypothesized that species with larger photosynthetic plasticity exhibit better growth after gap formation and lower survivorship in the shade understorey of a cool-temperate deciduous forest. We created gaps by felling canopy trees and studied the relationship between the photosynthetic response and the subsequent growth rate of seedlings. Naturally growing seedlings of six deciduous woody species were used and their mortality was examined for 8 years. The light-saturated rate of photosynthesis (Pmax) and the relative growth rate (RGR) of the seedlings of all study species increased at gap plots. The extent of these increases varied among the species. The stimulation of RGR over 4 years after gap formation was strongly correlated with change in photosynthetic capacity of newly expanded leaves. The increase in RGR and Pmax correlated with the 8-year mortality at control plots. These results suggest a trade-off between photosynthetic plasticity and the understorey shade tolerance. Gap-demanding species may acquire photosynthetic plasticity, sacrificing shade tolerances, whereas gap-independent species may acquire

  4. Statistical analysis of texture in trunk images for biometric identification of tree species.

    Science.gov (United States)

    Bressane, Adriano; Roveda, José A F; Martins, Antônio C G

    2015-04-01

    The identification of tree species is a key step for sustainable management plans of forest resources, as well as for several other applications that are based on such surveys. However, the present available techniques are dependent on the presence of tree structures, such as flowers, fruits, and leaves, limiting the identification process to certain periods of the year. Therefore, this article introduces a study on the application of statistical parameters for texture classification of tree trunk images. For that, 540 samples from five Brazilian native deciduous species were acquired and measures of entropy, uniformity, smoothness, asymmetry (third moment), mean, and standard deviation were obtained from the presented textures. Using a decision tree, a biometric species identification system was constructed and resulted to a 0.84 average precision rate for species classification with 0.83accuracy and 0.79 agreement. Thus, it can be considered that the use of texture presented in trunk images can represent an important advance in tree identification, since the limitations of the current techniques can be overcome.

  5. Contribution of foliar leaching and dry deposition to sulfate in net throughfall below deciduous trees

    International Nuclear Information System (INIS)

    Garten, C.T. Jr.; Bondietti, E.A.; Lomax, R.D.

    1988-01-01

    Experiments were conducted at Walker Branch Watershed, Tennessee in 1986 with radioactive 35 S to quantify the contribution of foliar leaching and dry deposition to sulfate (SO 4 2- ) in net throughfall (NTF). Two red maple (Acer rubrum) and two yellow poplar (Liriodendron tulipifera) trees (12-15 m tall) were radiolabeled by stem well injection. Total S and 35 S were measured in leaves; 35 S and SO 4 2- were measured in throughfall (THF). The contribution of foliar leaching to SO 4 2- in NTF, THF minus incident precipitation, was estimated by isotope dilution of 35 S in NTF arising from nonradioactive S in dry deposition. The per cent contribution of foliar leaching to SO 4 2- in NTF was greatest during the week following isotope labeling and during the period of autumn leaf fall. During the growing season, foliar leaching accounted for 80% of the SO 4 2- in NTF beneath the study trees. Dry deposition of S to these tree species can be reasonably approximated during summer from the measurement of SO 4 2- flux in NTF. (author)

  6. EAB induced tree mortality impacts ecosystem respiration and tree water use in an experimental forest

    Science.gov (United States)

    Charles E. Flower; Douglas J. Lynch; Kathleen S. Knight; Miquel A. Gonzales-Meler

    2011-01-01

    The invasive emerald ash borer (Agrilus planipennis Fairmaire, EAB) has been spreading across the forest landscape of the Midwest resulting in the rapid decline of ash trees (Fraxinus spp.). Ash trees represent a dominant riparian species in temperate deciduous forests of the Eastern United States (USDA FIA Database). Prior...

  7. Preliminary study of elemental composition in tree leaves for using as bio monitor for air pollution

    International Nuclear Information System (INIS)

    Chueinta, Wanna; Bunprapob, Supamatthree

    2004-10-01

    The use of plant tissue as biological monitor of air pollution has been of interest world wild. The study on chemical composition of such biological monitor may provide important information on the levels and pathways of a variety of pollutants including heavy metals and trace toxic elements in atmosphere. The appropriate bio monitors are such as herbaceous plants, tree leaves, bryophytes and lichens, with their possible advantages and/or limitations. In this research an investigation of element composition in leaves was performed. The technique of Instrument Neutron Activation Analysis (INAA) was developed to determine heavy metal and trace elements in 8 species of tree leaves collected from 3 different locations. From the experiments, it was found that content of elements might vary depending on species and environment. Some specific elements are discussed and compared in this report

  8. ENVIRONMENTAL MONITORING USING LINDEN TREE LEAVES AS NATURAL TRAPS OF ATMOSPHERIC DEPOSITION: A PILOT STUDY IN TRANSILVANIA, ROMANIA

    Directory of Open Access Journals (Sweden)

    MIHÁLY BRAUN

    2007-12-01

    Full Text Available Atmospheric pollution caused by toxic elements is an emerging problem of concern. Tree leaves have been widely used as indicator of atmospheric pollutions and they are effective alternatives to the moreusual biomonitoring methods. Tree leaves can be used as natural traps of atmospheric deposition. Elemental composition of dust deposited onto leaf surfaces can be used to characterize the urban environment. A pilot survey including 16 Romanian settlements was carried out in order to evaluate the characteristics and sources of air pollutants. Tree leaves (Tilia tomentosa, Tilia cordata, Tilia platyphyllos were collected and used for the measurements. Elemental analyses were carried out by ICP-OES and ICP-MS. Principal component and discriminant analyses were used to characterizing and estimating the level of pollution. Settlements were grouped on the basis of discriminant function values. Multivariate comparison of chemical data ordered the settlements into 3 main groups, which showed a systematic geographic distribution.

  9. Caloric content of leaves of five tree species from the riparian vegetation in a forest fragment from South Brazil

    Directory of Open Access Journals (Sweden)

    Leandro Fabrício Fiori

    2015-09-01

    Full Text Available Abstract Aim: The measurement of the caloric content evidences the amount of energy that remains in the leaf and that can be released to the aquatic trophic chain. We assessed the energy content of leaves from five riparian tree species of a forest fragment in south Brazil and analyzed whether leaf caloric content varied between leaf species and between seasons (dry and wet. The studied sites are located in Northwest of Paraná State, inside a Semi-Deciduous Forest fragment beside two headwater streams. Methods Sampling sites were located along the riparian vegetation of these two water bodies, and due to its proximity and absence of statistical differences of caloric values, analyzed as one compartment. Results Caloric content varied significantly among species and among all pairs of species, with exception of Nectandra cuspidata Ness and Calophyllum brasiliensis Cambess. Two species presented significant differences between seasons, Sloanea guianensis (Aubl. Ben and Calophyllum brasiliensis Cambess. Conclusions The absence of significant seasonal differences of energy content for some species may be due to the characteristics of the tropical forest, in which temperature did not varied dramatically between seasons. However, the energy differed between species and seasons for some species, emphasizing the necessity of a preliminary inspection of energy content, before tracing energy fluxes instead of using a single value to all species from riparian vegetation.

  10. Ecophysiological studies on photosynthesis and pigment adaptation of light and shade leaves; Oekophysiologische Untersuchungen zur Photosynthese und Pigment-Adaptation bei Licht- und Schattenblaettern

    Energy Technology Data Exchange (ETDEWEB)

    Knapp, M.

    2005-07-01

    Photosynthetic function and pigment adaptation, as well as several other leaf parameters of light and shade adapted leaves of trees were studied under different environmental conditions. These measurements were performed primarily on a solitary standing beech during a summer drought stress period and an autumnal partial regeneration of physiological activity. Mainly investigated were beech leaves, sun leaves growing at the south side of the tree and shade leaves from the interior of the crown, since beech leaves show the strongest physiological light and shade adaptation responses among all deciduous trees. Similar adaptation studies were also performed with red, light-exposed, anthocyanin-containing leaves of the herbaceous purple foliage plant Perilla (beefsteak plant, Chinese basil) and some other plant species with either slightly or more red leaves, in order to check whether the accumulation of anthocyanins in the upper leaf epidermis of sun exposed-leaves blocks the high-light induced formation of sun-type chloroplasts. The latter are known to possess a much higher photosynthetic capacity and a different pigment composition as compared to shade-type chloroplasts of shaded green leaves. Special consideration was given to the natural drought stress effects usually occurring in the summer period (ca. end of July to end of August), caused by a combination of unfavourable weather conditions, such as a longer heat stress, with strong solar radiation and a very low rain precipitation lying clearly below the annual mean. The obtained research results provided new facts for a better understanding of the physiology of photosynthesis in sun and shade leaves of beech at both normal physiological conditions (June) and at environmental stress conditions (July, August), as well as the effect of anthocyanins on the formation of sun-type chloroplasts and their photosynthetic pigments (chlorophylls and carotenoids) in light-exposed purple foliage. (orig.)

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

    Energy Technology Data Exchange (ETDEWEB)

    Kadota, M; Ohta, K

    1972-01-01

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

  12. Comparison of saproxylic beetle assemblages on four different broad-leaved tree species in south-eastern Sweden

    OpenAIRE

    Johansson, Helena

    2011-01-01

    Old hollow trees have declined in Europe and many saproxylic (wood-dwelling) beetles dependent on them are threatened. Several studies have been done on old hollow oaks and they have been shown to harbour a species-rich saproxylic beetle fauna. However, other broad-leaved trees might also be important to consider as supporting habitats. The aim of this study was to investigate to what extent saproxylic beetles are tree genus specialists. Pitfall traps and window traps were used to compare the...

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

    Science.gov (United States)

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

    2006-05-01

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

  14. The principles for creation of fire-prevention forest belts with barriers of deciduous species for protection from crown fires

    Directory of Open Access Journals (Sweden)

    S. N. Sannikov

    2017-10-01

    Full Text Available The article discuss one of the priority security problems in Russia, which is elaboration of the strategic system of the forest and society safeguards from catastrophic forest crown fires in connection with rapid climate warming. It is postulated, that a most effective and reliable barrier for the dispersal of the intensive crown fire in a coniferous forest massive can be a sufficiently wide strip of deciduous tree species – «deciduous forest barrier», which has phytomass capable of absorbing crown fire energy and transforming them to surface fire, which may be extinguished by technical means. The actuality of the natural study of the transition parameters from the crown fire to surface fire has been noted, depending on climate, fire intensity and the deciduous barrier structure. The results of the quantitative natural investigation of the consequences of catastrophic crown fires of 2004 in the island pine forests of forest-steppe zone in Kurgan Oblast, which passed through the belt of 50–70 year-old birch stands of middle density, has been cited and formalized mathematically. It has been shown, that 150 m width of deciduous forest barrier is necessary as a minimum for the reliable transition of the high intensive front crown fire to surface fire in the forest-steppe conditions of the Western Siberia, but this width reduces with a decreasing heating effect. It has been proposed to create the complex fire-prevention forest belts of different construction for the protection of forests, industrial objects and settlements. Besides a basic deciduous barrier, their structure should include technologically necessary buffer zones and zones for the localization and extinguishing surface fire, which stop a crown fire. It has been recommended to use natural regeneration of deciduous tree species, as a most effective and non-deficient method for the creation of deciduous forest barriers in the predominant forest types, except the lichen pine forests

  15. Are temperate canopy spiders tree-species specific?

    Science.gov (United States)

    Mupepele, Anne-Christine; Müller, Tobias; Dittrich, Marcus; Floren, Andreas

    2014-01-01

    Arboreal spiders in deciduous and coniferous trees were investigated on their distribution and diversity. Insecticidal knock-down was used to comprehensively sample spiders from 175 trees from 2001 to 2003 in the Białowieża forest and three remote forests in Poland. We identified 140 species from 9273 adult spiders. Spider communities were distinguished between deciduous and coniferous trees. The richest fauna was collected from Quercus where beta diversity was also highest. A tree-species-specific pattern was clearly observed for Alnus, Carpinus, Picea and Pinus trees and also for those tree species that were fogged in only four or three replicates, namely Betula and Populus. This hitherto unrecognised association was mainly due to the community composition of common species identified in a Dufrene-Legendre indicator species analysis. It was not caused by spatial or temporal autocorrelation. Explaining tree-species specificity for generalist predators like spiders is difficult and has to involve physical and ecological tree parameters like linkage with the abundance of prey species. However, neither did we find a consistent correlation of prey group abundances with spiders nor could differences in spider guild composition explain the observed pattern. Our results hint towards the importance of deterministic mechanisms structuring communities of generalist canopy spiders although the casual relationship is not yet understood.

  16. Activity, polypeptide and gene identification of thylakoid Ndh complex in trees: potential physiological relevance of fluorescence assays.

    Science.gov (United States)

    Serrot, Patricia H; Sabater, Bartolomé; Martín, Mercedes

    2012-09-01

    Three evergreen (Laurus nobilis, Viburnum tinus and Thuja plicata) and two autumnal abscission deciduous trees (Cydonia oblonga and Prunus domestica) have been investigated for the presence (zymogram and immunodetection) and functionality (post-illumination chlorophyll fluorescence) of the thylakoid Ndh complex. The presence of encoding ndh genes has also been investigated in T. plicata. Western assays allowed tentative identification of zymogram NADH dehydrogenase bands corresponding to the Ndh complex after native electrophoresis of solubilized fractions from L. nobilis, V. tinus, C. oblonga and P. domestica leaves, but not in those of T. plicata. However, Ndh subunits were detected after SDS-PAGE of thylakoid solubilized proteins of T. plicata. The leaves of the five plants showed the post-illumination chlorophyll fluorescence increase dependent on the presence of active Ndh complex. The fluorescence increase was higher in autumn in deciduous, but not in evergreen trees, which suggests that the thylakoid Ndh complex could be involved in autumnal leaf senescence. Two ndhB genes were sequenced from T. plicata that differ at the 350 bp 3' end sequence. Comparison with the mRNA revealed that ndhB genes have a 707-bp type II intron between exons 1 (723 bp) and 2 (729 bp) and that the UCA 259th codon is edited to UUA in mRNA. Phylogenetically, the ndhB genes of T. plicata group close to those of Metasequoia, Cryptomeria, Taxodium, Juniperus and Widdringtonia in the cupresaceae branch and are 5' end shortened by 18 codons with respect to that of angiosperms. Copyright © Physiologia Plantarum 2012.

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

    Science.gov (United States)

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

    2015-12-01

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

  18. Estimates of ion sources in deciduous and coniferous throughfall

    Science.gov (United States)

    Puckett, L.J.

    1990-01-01

    Estimates of external and internal sources of ions in net throughfall deposition were derived for a deciduous and coniferous canopy by use of multiple regression. The externel source component appears to be dominated by dry deposition of Ca2+, SO2 and NO3- during dormant and growing seasons for the two canopy types. Increases in the leaching rates of K+ and Mg2+ during the growing season reflect the presence of leaves in the deciduous canopy and increased physiological activity in both canopies. Internal leaching rates for SO42- doubled during the growing season presumably caused by increased physiological activity and uptake of SO2 through stomates. Net deposition of SO42- in throughfall during the growing season appears highly dependent on stomatal uptake of SO2. Estimates of SO2 deposition velocities were 0.06 cm s-1 and 0.13 cm s-1 for the deciduous and coniferous canopies, respectively, during the dormant season, and 0.30 cm s-1 and 0.43 cm s-1 for the deciduous and coniferous canopies, respectively, during the growing season. For the ions of major interest with respect to ecosystem effects, namely H+, NO3- and SO42-, precipitation inputs generally outweighed estimates of dry deposition input. However, net throughfall deposition of NO3- and SO42- accounted for 20-47 and 34-50 per cent, respectively, of total deposition of those ions. Error estimates of ion sources were at least 50-100 per cent and the method is subject to several assumptions and limitations.

  19. Estimation of water content in the leaves of fruit trees using infra-red images

    International Nuclear Information System (INIS)

    Muramatsu, N.; Hiraoka, K.

    2006-01-01

    A method was developed to evaluate water contents of fruit trees using infra-red photography. The irrigation of potted satsuma mandarin trees and grapevines was suppressed to induce water stress. During the drought treatment the leaf edges of basal parts of the shoots of grapevines became necrotic and the area of necrosis extended as the duration of stress increased. Necrosis was clearly distinguished from the viable areas on infra-red images. In satsuma mandarin, an abscission layer formed at the basal part of the petiole, then the leaves fell. Thus, detailed analysis was indispensable for detecting of the leaf water content. After obtaining infra-red images of satsuma mandarin leaves with or without water stress, a background treatment (subtraction of the background image) was performed on the images, then the average brightness of the leaf was determined using image analyzing software (Image Pro-plus). Coefficient correlation between the water status index using the infra-red camera and water content determined from dry weight and fresh weight of leaves was significant (r = 0.917 for adaxial surface data and r = 0.880 for abaxial surface data). These data indicate that infra-red photography is useful for detecting the degree of plant water stress

  20. Differential growth responses to water balance of coexisting deciduous tree species are linked to wood density in a Bolivian tropical dry forest.

    Science.gov (United States)

    Mendivelso, Hooz A; Camarero, J Julio; Royo Obregón, Oriol; Gutiérrez, Emilia; Toledo, Marisol

    2013-01-01

    A seasonal period of water deficit characterizes tropical dry forests (TDFs). There, sympatric tree species exhibit a diversity of growth rates, functional traits, and responses to drought, suggesting that each species may possess different strategies to grow under different conditions of water availability. The evaluation of the long-term growth responses to changes in the soil water balance should provide an understanding of how and when coexisting tree species respond to water deficit in TDFs. Furthermore, such differential growth responses may be linked to functional traits related to water storage and conductance. We used dendrochronology and climate data to retrospectively assess how the radial growth of seven coexisting deciduous tree species responded to the seasonal soil water balance in a Bolivian TDF. Linear mixed-effects models were used to quantify the relationships between basal area increment and seasonal water balance. We related these relationships with wood density and sapwood production to assess if they affect the growth responses to climate. The growth of all species responded positively to water balance during the wet season, but such responses differed among species as a function of their wood density. For instance, species with a strong growth response to water availability averaged a low wood density which may facilitate the storage of water in the stem. By contrast, species with very dense wood were those whose growth was less sensitive to water availability. Coexisting tree species thus show differential growth responses to changes in soil water balance during the wet season. Our findings also provide a link between wood density, a trait related to the ability of trees to store water in the stem, and wood formation in response to water availability.

  1. Buffer nitrogen solubility, in vitro ruminal partitioning of nitrogen and in vitro ruminal biological activity of tannins in leaves of four fodder tree species.

    Science.gov (United States)

    Cudjoe, N; Mlambo, V

    2014-08-01

    This study explores the chemical composition, buffer N solubility, in vitro ruminal N degradability and in vitro ruminal biological activity of tannins in leaves from Gliricidia sepium, Leucaena leucocephala, Morus alba and Trichanthera gigantea trees. These tree leaves are a potential protein source for ruminants, but their site-influenced nutritive value is largely unknown. Leucaena leucocephala leaves had the highest N content (42.1 g/kg DM), while T. gigantea leaves had the least (26.1 g/kg DM). Leucaena leucocephala had the highest buffer solubility index (20%), while 10% of the total N in leaves of the other three species was soluble. The rapidly fermentable N fraction 'a' was highest in M. alba leaves (734.9 g/kg DM) and least in T. gigantea leaves (139.5 g/kg DM). The rate of fermentation (c) was highest for M. alba (7%/hours) leaves. No significant correlations were recorded between buffer solubility index of N and in vitro ruminal N degradability parameters: a, b, and c. The highest response to tannin inactivation using polyethylene glycol, in terms of percentage increase in 36-hours cumulative gas production, was recorded in M. alba (39%) and T. gigantea (38%) leaves. It was concluded that buffer solubility of N is not a good indicator of ruminal N degradation in the leaves of these tree species. Leaves of M. alba could be more valuable as a source of rapidly fermentable N when animals are offered low-protein, high-fibre diets compared with other tree species evaluated in the current study. However, when feeding M. alba leaves, the role of tannins must be considered because these secondary plant compounds showed significant in vitro ruminal biological activity. Journal of Animal Physiology and Animal Nutrition © 2013 Blackwell Verlag GmbH.

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

    Science.gov (United States)

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

    2016-05-01

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

  3. Technetium-99 cycling in maple trees: Characterization of changes in chemical form

    International Nuclear Information System (INIS)

    Garten, C.T. Jr.; Lomax, R.D.

    1989-01-01

    Prior field studies near an old radioactive waste disposal site at Oak Ridge, TN, indicated that following root uptake, metabolism by deciduous trees rendered 99Tc less biogeochemically mobile than expected, based on chemistry of the pertechnetate (TcO-4) anion. Subsequently, the form of technetium (Tc) in maple tree (Acer sp.) sap, leaves, wood and forest leaf litter was characterized using one or more of the following methods: dialysis, physical fractionation, chemical extraction, gel permeation chromatography, enzymatic extraction, or thin layer chromatography (TLC) on silica gel. Chromatography (Sephadex G-25) of TcO-4 incubated in vitro with tree sap showed it to behave similar to TcO-4 anion. When labeled wood and leaf tissues were processed using a tissue homogenizer, 15% and 40%, respectively, of the Tc was solubilized into phosphate buffer. Most (65% to 80%) of the solubilized Tc passing a 0.45-micron filter also passed through an ultrafiltration membrane with a nominal molecular weight cutoff of 10,000 atomic mass units (amu). A majority (72% to 80%) of the Tc in wood could be chemically removed by successive extractions with ethanol, water and weak mineral acid. These same extractants removed only 23% to 31% of the Tc from maple leaves or forest floor leaf litter. Most of the Tc in leaves and leaf litter was removed only by strongly alkaline reagents typically used to release structural polysaccharides (hemicelluloses) from plant tissues. Chromatography (Sephadex G-25) of the ethanol-water extract from wood and the alkaline extract from leaves demonstrated that Tc in these extracts was not principally TcO-4 but was complexed with molecules greater than 1000 amu. Incubations of leaf and wood homogenates with protease approximately doubled the amount of Tc released from contaminated tissues

  4. Variation in content of macronutrients of guava tree leaves, in function of type and time of storage

    Directory of Open Access Journals (Sweden)

    Henrique Antunes de Souza

    2010-10-01

    Full Text Available Leaf analysis for perennial crops such as the guava tree is an important tool. It was used to evaluate the influence of the type of packaging (with or without refrigerator and storage time after collection on the macronutrient composition of guava tree leaves. The leaf sampling was carried out on a commercial guava tree (cv. Paluma, collecting the third pair of recently matured leaves in full bloom. The experimental design was in randomized blocks, subdivided according to the type of packaging (with or without refrigerator and further subdivided into eight storage times before washing (zero, 6, 12, 24, 48, 72, 96 and 168h after sampling, with four replications. The storage time significantly affected the concentration of leaf nitrogen, calcium and sulfur. Moreover, the type and time of conditioning (with or without refrigerator affected only the magnesium. In general, storage fot up to 12h before washing produced no significant changes in the levels of macronutrients.

  5. Variation in content of macronutrients of guava tree leaves, in function of type and time of storage

    Directory of Open Access Journals (Sweden)

    Henrique Antunes de Souza

    2010-09-01

    Full Text Available Leaf analysis for perennial crops such as the guava tree is an important tool. It was used to evaluate the influence of the type of packaging (with or without refrigerator and storage time after collection on the macronutrient composition of guava tree leaves. The leaf sampling was carried out on a commercial guava tree (cv. Paluma, collecting the third pair of recently matured leaves in full bloom. The experimental design was in randomized blocks, subdivided according to the type of packaging (with or without refrigerator and further subdivided into eight storage times before washing (zero, 6, 12, 24, 48, 72, 96 and 168h after sampling, with four replications. The storage time significantly affected the concentration of leaf nitrogen, calcium and sulfur. Moreover, the type and time of conditioning (with or without refrigerator affected only the magnesium. In general, storage fot up to 12h before washing produced no significant changes in the levels of macronutrients.

  6. Distribution and uptake dynamics of mercury in leaves of common deciduous tree species in Minnesota, U.S.A.

    Science.gov (United States)

    Aicam Laacouri; Edward A. Nater; Randall K. Kolka

    2013-01-01

    A sequential extraction technique for compartmentalizing mercury (Hg) in leaves was developed based on a water extraction of Hg from the leaf surface followed by a solvent extraction of the cuticle. The bulk of leaf Hg was found in the tissue compartment (90-96%) with lesser amounts in the surface and cuticle compartments. Total leaf concentrations of Hg varied among...

  7. DIVERSITY AND ECOLOGICAL DETERMINANTS OF DEAD WOOD FUNGI IN TREE NATURAL RESERVES OF BROAD LEAVED FORESTS FROM SUCEAVA COUNTY

    Directory of Open Access Journals (Sweden)

    Ciprian BÎRSAN

    2014-12-01

    Full Text Available Dead wood fungi have a major importance for forests biodiversity as they produce wood degradation in forest habitats. In this paper are presented some aspects related to the diversity of dead wood fungi in tree deciduous forest types from tree natural reserves (Crujana, Dragomirna and Zamostea from Suceava County and the effect of some ecological factors (host tree, diameter and decomposition degree of the dead wood and some microclimatic characteristics of sites on their occurrence and diversity. Investigations carried out in 2013 resulted in the identification of 44 lignicolous fungi species. Analysis of similarities between lingnicolous fungi species from the investigated natural reserves (by hierarchical clustering shows a separation of three fungi groups, depending on the host-trees species. The effect of the tree host species was highlighted also by detrended correspondence analysis, which, in addition presented the existence of an altitudinal gradient and a weaker effect of site conditions (slope and aspect and microclimatic variables (solar radiation on dead wood fungi occurrence. The effect of diameter and decomposition degree of fallen trunks and branches on dead wood fungi species was investigated using the redundancy analysis showing that wood debris with large surfaces are more easily colonized by the fungi species developing large sporocarps compared to small branches with low diameters colonized only by few or a single fungus species.

  8. Apiose and mono-O-methyl sugars as minor constituents of the leaves of deciduous trees and various other species.

    Science.gov (United States)

    Bacon, J S; Cheshire, M V

    1971-09-01

    1. Leaves of a number of species were hydrolysed with aqueous sulphuric acid and the resulting mixtures of sugars were fractionated by chromatography on activated charcoal. Paper chromatography of the fractions showed the presence in all the hydrolysates of minor constituents with R(F) values similar to or greater than those of the common hexoses and pentoses. 2. Two of these were identified as 2-O-methylxylose and 2-O-methylfucose. Estimates of the amounts present in whole leaves, and in fractions prepared from them, showed that they were associated with the hemicelluloses. 3. A third constituent was identified, by the formation of its di-isopropylidene derivative, as apiose. It also was associated chiefly with the hemicellulose fraction; none could be found in aqueous extracts from leaves of Tilia vulgaris, nor in aqueous extracts of Zostera marina, in which apiose is a major constituent of the water-insoluble polysaccharide. 4. A further constituent, after further purification by preparative paper chromatography, was tentatively identified, by gas-liquid chromatography of derivatives, as 3-O-methylgalactose, and was probably accompanied by small amounts of 4-O-methylgalactose. 5. These observations confirm the widespread occurrence of 2-O-methylxylose, 2-O-methylfucose and apiose, but 3-O-methylgalactose was hitherto known only in slippery-elm mucilage, and 4-O-methylgalactose in soil polysaccharides. Some experiments on the digestion of leaf hemicellulose fractions by snail crop-juice suggested that the mono-O-methyl sugars might confer resistance to enzymic degradation.

  9. Direct Deposition Effect on the Distribution of Radiocesium in Persimmon Trees and the Effective Half-life

    Energy Technology Data Exchange (ETDEWEB)

    Tagami, Keiko; Uchida, Shigeo [National Institute of Radiological Sciences, Anagawa 4-9-1, Inage-ku, Chiba 263-7444 (Japan)

    2014-07-01

    Radiocesium ({sup 137}Cs) concentrations in persimmon tree tissues collected at Chiba, about 220 km south from Fukushima Daiichi nuclear power plant (FDNPP), were measured to obtain half-life of radiocesium in the trees. Persimmon (Diospyros kaki) is a deciduous tree and bears edible fruits in autumn. There were no leaves when the sampling area was received the radioactive fallout in March 2011 due to the FDNPP accident; the amount of {sup 137}Cs radioactivity in this area was ca. 13 kBq/m{sup 3} Both {sup 137}Cs and {sup 134}Cs were found in the newly emerged shoots of the persimmon trees collected at 26 April 2011 mainly due to foliar uptake. The concentrations were 1.1 kBq/kg-dry for {sup 137}Cs and 1.3 kBq/kg-dry for {sup 134}Cs. After that, continuous sampling of leaves, branches and fruits of the persimmon trees had been carried out for two years. Immediately after the collection, samples were transferred to our laboratory and weighed to obtain fresh weight. Leaf samples were usually separated into two portions; one portion was washed with tap water to remove dust from the surface and the other portion was not treated. For fruit samples, if it is possible, fruit flesh, peal and non-edible part were separated. All the samples were oven-dried at 80 deg. C for three days at least. Each dried sample was chopped into fine pieces, mixed well, and then transferred into plastic vessels separately. Radioactivity concentration was measured by a Ge-detecting system (Seiko EG and G Ortec) using 3000-40000 s counting intervals. By August 14, 2013, about 140 samples were collected from the trees; about 60 samples were leaves (both washed and untreated). Radiocesium concentrations in tree leaves decreased with time, and the effective half-life was about 190 d; the value was similar to those in branches (160 d for new branches, and 250 d for 1-2 y.o. branches) and fruits (250 d for fruit flesh and 230 d for peals). Thus we concluded that the half-life of radiocesium in

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

    Science.gov (United States)

    Jin, Yi; Qian, Hong; Yu, Mingjian

    2015-01-01

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

  11. Apps for Angiosperms: The Usability of Mobile Computers and Printed Field Guides for UK Wild Flower and Winter Tree Identification

    Science.gov (United States)

    Stagg, Bethan C.; Donkin, Maria E.

    2017-01-01

    We investigated usability of mobile computers and field guide books with adult botanical novices, for the identification of wildflowers and deciduous trees in winter. Identification accuracy was significantly higher for wildflowers using a mobile computer app than field guide books but significantly lower for deciduous trees. User preference…

  12. Dalbergia latifolia Roxb. (East Indian Rosewood) of Leguminosae is ...

    Indian Academy of Sciences (India)

    Dalbergia latifolia Roxb. (East Indian Rosewood) of Leguminosae is a large deciduous or nearly evergreen tree that grows in mixed deciduous forests with teak. Leaves are compound. The creamy white flowers are borne on branched inflorescences. The indehiscent dry pod bears. 1-4 seeds. Inset - a juvenile plant.

  13. The steady and vibrating statuses of tulip tree leaves in wind

    Directory of Open Access Journals (Sweden)

    Yuanyuan Zhu

    2017-01-01

    Full Text Available The study of tree leaf aerodynamics is useful to tree protection, solar panel design and development of new power generation technology. 73 tulip leaves were tested in suspended condition and with front as well as back surface of the lamina facing wind. Three types of vibrating statuses, two types of steady statuses, and five critical wind speeds were observed. The existence probabilities of the statuses and criticals, the probability density distribution of every critical over the range of wind speed 0–27 m/s, and the expected values of the criticals were obtained by statistics. The critical Reynolds number, defined by critical wind speed and lamina length, shows an increasing trend with increasing the lamina area or length to width ratio of the lamina, but it shows no trend of increase or decrease with increasing the length ratio of petiole to lamina.

  14. Stable carbon isotope ratios and intrinsic water-use efficiency of Miocene fossil leaves compared to modern congeners

    Energy Technology Data Exchange (ETDEWEB)

    Marshall, J.D.; Zhang, J.; Rember, W.C.; Jennings, D.; Larson, P. (Univ. of Idaho, Moscow, ID (United States))

    1994-06-01

    Miocene fossil leaves of forest trees were extracted from the Clarkia, Idaho fossil beds and their stable carbon isotope ratios were analyzed. Fossils had higher lignin concentrations and lower cellulose concentrations that modern leaves due to diagenesis and the HF used to extract the fossils. Therefore, [delta][sup 13]C of extracted fossil lignin was compared to that of modern lignin. Fossil lignin [delta][sup 13]C was significantly different from that of congeneric modern leaves (paired t-test, P<0.0001), but was 1.9% less negative. Gymnosperms (Metasequoia, Taxodium) were less negative than angiosperms (e.g., Magnolia, Quercus, Acer, Persea), but no difference between evergreen and deciduous species was detected. Using published estimates of the concentration and [delta][sup 13]C of atmospheric CO[sub 2] during the Miocene was estimated the CO[sub 2] partial pressure gradient across the stomata (intrinsic water-use efficiency). Intrinsic water-use efficiency was at least 70% higher during this past [open quotes]greenhouse[close quotes] period than at present.

  15. Differential growth responses to water balance of coexisting deciduous tree species are linked to wood density in a Bolivian tropical dry forest.

    Directory of Open Access Journals (Sweden)

    Hooz A Mendivelso

    Full Text Available A seasonal period of water deficit characterizes tropical dry forests (TDFs. There, sympatric tree species exhibit a diversity of growth rates, functional traits, and responses to drought, suggesting that each species may possess different strategies to grow under different conditions of water availability. The evaluation of the long-term growth responses to changes in the soil water balance should provide an understanding of how and when coexisting tree species respond to water deficit in TDFs. Furthermore, such differential growth responses may be linked to functional traits related to water storage and conductance. We used dendrochronology and climate data to retrospectively assess how the radial growth of seven coexisting deciduous tree species responded to the seasonal soil water balance in a Bolivian TDF. Linear mixed-effects models were used to quantify the relationships between basal area increment and seasonal water balance. We related these relationships with wood density and sapwood production to assess if they affect the growth responses to climate. The growth of all species responded positively to water balance during the wet season, but such responses differed among species as a function of their wood density. For instance, species with a strong growth response to water availability averaged a low wood density which may facilitate the storage of water in the stem. By contrast, species with very dense wood were those whose growth was less sensitive to water availability. Coexisting tree species thus show differential growth responses to changes in soil water balance during the wet season. Our findings also provide a link between wood density, a trait related to the ability of trees to store water in the stem, and wood formation in response to water availability.

  16. Differential Growth Responses to Water Balance of Coexisting Deciduous Tree Species Are Linked to Wood Density in a Bolivian Tropical Dry Forest

    Science.gov (United States)

    Mendivelso, Hooz A.; Camarero, J. Julio; Royo Obregón, Oriol; Gutiérrez, Emilia; Toledo, Marisol

    2013-01-01

    A seasonal period of water deficit characterizes tropical dry forests (TDFs). There, sympatric tree species exhibit a diversity of growth rates, functional traits, and responses to drought, suggesting that each species may possess different strategies to grow under different conditions of water availability. The evaluation of the long-term growth responses to changes in the soil water balance should provide an understanding of how and when coexisting tree species respond to water deficit in TDFs. Furthermore, such differential growth responses may be linked to functional traits related to water storage and conductance. We used dendrochronology and climate data to retrospectively assess how the radial growth of seven coexisting deciduous tree species responded to the seasonal soil water balance in a Bolivian TDF. Linear mixed-effects models were used to quantify the relationships between basal area increment and seasonal water balance. We related these relationships with wood density and sapwood production to assess if they affect the growth responses to climate. The growth of all species responded positively to water balance during the wet season, but such responses differed among species as a function of their wood density. For instance, species with a strong growth response to water availability averaged a low wood density which may facilitate the storage of water in the stem. By contrast, species with very dense wood were those whose growth was less sensitive to water availability. Coexisting tree species thus show differential growth responses to changes in soil water balance during the wet season. Our findings also provide a link between wood density, a trait related to the ability of trees to store water in the stem, and wood formation in response to water availability. PMID:24116001

  17. Seasonality of nutrients in leaves and fruits of apple trees

    Directory of Open Access Journals (Sweden)

    Nachtigall Gilmar Ribeiro

    2006-01-01

    Full Text Available The nutrient accumulation curves of apple trees are good indicators of plant nutrient demand for each developmental stage. They are also a useful tool to evaluate orchard nutritional status and to estimate the amount of soil nutrient removal. This research aimed at evaluating the seasonality of nutrients in commercial apple orchards during the agricultural years of 1999, 2000, and 2001. Therefore, apple tree leaves and fruits of three cultivars 'Gala', 'Golden Delicious' and 'Fuji' were weekly collected and evaluated for fresh and dry matter, fruit diameter and macronutrient (N, P, K, Ca and Mg and micronutrient (B, Cu, Fe, Mn, and Zn concentrations. Leaf and fruit sampling started one or two weeks after full bloom, depending on the cultivar, and ended at fruit harvest or four weeks later (in the case of leaf sampling. In general, leaf concentrations of N, P, K, Cu, and B decreased; Ca increased; and Mg, Fe, Mn, and Zn did vary significantly along the plant vegetative cycle. In fruits, the initial nutrient concentrations decreased quickly, undergoing slow and continuous decreases and then remaining almost constant until the end of fruit maturation, indicating nutrient dilution, once the total nutrient accumulation increased gradually with fruit growth. Potassium was the nutrient present in highest quantities in apple tree fruits and thus, the most removed from the soil.

  18. AMPK modulatory activity of olive–tree leaves phenolic compounds: Bioassay-guided isolation on adipocyte model and in silico approach

    Science.gov (United States)

    Jiménez-Sánchez, Cecilia; Olivares-Vicente, Mariló; Rodríguez-Pérez, Celia; Herranz-López, María; Lozano-Sánchez, Jesús; Segura-Carretero, Antonio; Fernández-Gutiérrez, Alberto; Encinar, José Antonio; Micol, Vicente

    2017-01-01

    Scope Olive-tree polyphenols have demonstrated potential for the management of obesity-related pathologies. We aimed to explore the capacity of Olive-tree leaves extract to modulate triglyceride accumulation and AMP-activated protein kinase activity (AMPK) on a hypertrophic adipocyte model. Methods Intracellular triglycerides and AMPK activity were measured on the hypertrophic 3T3-L1 adipocyte model by AdipoRed and immunofluorescence microscopy, respectively. Reverse phase high performance liquid chromatography coupled to time-of-flight mass detection with electrospray ionization (RP-HPLC-ESI-TOF/MS) was used for the fractionation of the extract and the identification of the compounds. In-silico molecular docking of the AMPK alpha-2, beta and gamma subunits with the identified compounds was performed. Results Olive-tree leaves extract decreased the intracellular lipid accumulation through AMPK-dependent mechanisms in hypertrophic adipocytes. Secoiridoids, cinnamic acids, phenylethanoids and phenylpropanoids, flavonoids and lignans were the candidates predicted to account for this effect. Molecular docking revealed that some compounds may be AMPK-gamma modulators. The modulatory effects of compounds over the alpha and beta AMPK subunits appear to be less probable. Conclusions Olive-tree leaves polyphenols modulate AMPK activity, which may become a therapeutic aid in the management of obesity-associated disturbances. The natural occurrence of these compounds may have important nutritional implications for the design of functional ingredients. PMID:28278224

  19. Seasonal and inter-annual variation of Beryllium-7 deposition in birch-tree leaves and grass in the northeast upland area of the Czech Republic

    Energy Technology Data Exchange (ETDEWEB)

    Poeschl, Michael, E-mail: poschl@mendelu.c [Department of Molecular Biology and Radiobiology, Faculty of Agronomy, Mendel University of Agriculture in Brno, Zemedelska 1, 61300 Brno (Czech Republic); Brunclik, Tomas, E-mail: brunclik@georadis.co [Georadis s.r.o., Hudcova 56b, 621 00 Brno (Czech Republic); Hanak, Jaromir, E-mail: jaromir.hanak@geology.c [Czech Geological Survey, Department of Environmental Geology and Geophysics, Leitnerova 22, 658 69 Brno (Czech Republic)

    2010-09-15

    The activity concentrations of Beryllium-7 ({sup 7}Be), a naturally occurring radioisotope produced in the atmosphere, were measured in leaves of birch-trees, above-ground parts of grass, soil and rainwater in the mountain massive Kralicky Sneznik (the northeast of the Czech Republic, altitude about 750 m) in the years of 2005, 2006 and 2007. Dried and ground samples of the plants and soils, and water samples from wet deposition were used to determine the {sup 7}Be content using a semiconductor gamma spectrometer. The {sup 7}Be values ranged from 147.0 to 279.6 Bq kg{sup -1}, from 48.7 to 740.8 Bq kg{sup -1}, from 2.1 to 8.7 Bq kg{sup -1}, and from 0.6 to 1.9 Bq kg{sup -1} in birch-tree leaves, grass samples, soils, and rainwater, respectively. Insignificant inter-annual variations but significant increase in the {sup 7}Be activity concentrations during the spring and summer months were observed in birch-tree leaves and grass samples. The seasonal variation of the {sup 7}Be concentrations in grass samples correlated (R{sup 2} = 0.4663 and 0.6489) with precipitation. No similar correlation was found for {sup 7}Be in birch-tree leaves. Beryllium-7 content in birch-tree leaves and in aerial parts of grass was mainly caused by direct transport of {sup 7}Be from wet deposition into aerial parts of the observed plants.

  20. Thermotolerance of apple tree leaves probed by chlorophyll a fluorescence and modulated 820 nm reflection during seasonal shift.

    Science.gov (United States)

    Duan, Ying; Zhang, Mengxia; Gao, Jin; Li, Pengmin; Goltsev, Vasilij; Ma, Fengwang

    2015-11-01

    During the seasonal shift from June to August, air temperatures increase. To explore how apple trees improve their thermotolerance during this shift, we examined the photochemical reaction capacity of apple tree leaves by simultaneous measurement of prompt chlorophyll fluorescence, delayed chlorophyll fluorescence, and modulated 820 nm reflection at varying temperatures. It was found that the reaction centers and antennae of photosystem II (PSII) and photosystem I (PSI), the donor side of PSII, the electron transfer capacity from QA to QB, and the reoxidation capacity of plastoquinol were all sensitive to heat stress, particularly in June. As the season shifted, apple tree leaves improved in thermotolerance. Interestingly, the acclimation to seasonal shift enhanced the thermotolerance of PSII and PSI reaction centers more than that of their antennae, and the activity of PSII more than that of PSI. This may be a strategy for plant adaptation to changes in environmental temperatures. In addition, results from prompt and delayed fluorescence, as well as modulated 820 nm reflection corroborate each other. We suggest that the simultaneous measurement of the three independent signals may provide more information on thermal acclimation mechanisms of photochemical reactions in plant leaves. Copyright © 2015 Elsevier B.V. All rights reserved.

  1. Chemometrics in biomonitoring: Distribution and correlation of trace elements in tree leaves.

    Science.gov (United States)

    Deljanin, Isidora; Antanasijević, Davor; Bjelajac, Anđelika; Urošević, Mira Aničić; Nikolić, Miroslav; Perić-Grujić, Aleksandra; Ristić, Mirjana

    2016-03-01

    The concentrations of 15 elements were measured in the leaf samples of Aesculus hippocastanum, Tilia spp., Betula pendula and Acer platanoides collected in May and September of 2014 from four different locations in Belgrade, Serbia. The objective was to assess the chemical characterization of leaf surface and in-wax fractions, as well as the leaf tissue element content, by analyzing untreated, washed with water and washed with chloroform leaf samples, respectively. The combined approach of self-organizing networks (SON) and Preference Ranking Organization Method for Enrichment Evaluation (PROMETHEE) aided by Geometrical Analysis for Interactive Aid (GAIA) was used in the interpretation of multiple element loads on/in the tree leaves. The morphological characteristics of the leaf surfaces and the elemental composition of particulate matter (PM) deposited on tree leaves were studied by using scanning electron microscopy (SEM) with energy dispersive spectroscopy (EDS) detector. The results showed that the amounts of retained and accumulated element concentrations depend on several parameters, such as chemical properties of the element and morphological properties of the leaves. Among the studied species, Tilia spp. was found to be the most effective in the accumulation of elements in leaf tissue (70% of the total element concentration), while A. hippocastanum had the lowest accumulation (54%). After water and chloroform washing, the highest percentages of removal were observed for Al, V, Cr, Cu, Zn, As, Cd and Sb (>40%). The PROMETHEE/SON ranking/classifying results were in accordance with the results obtained from the GAIA clustering techniques. The combination of the techniques enabled extraction of additional information from datasets. Therefore, the use of both the ranking and clustering methods could be a useful tool to be applied in biomonitoring studies of trace elements. Copyright © 2015 Elsevier B.V. All rights reserved.

  2. Remote estimation of crown size and tree density in snowy areas

    Science.gov (United States)

    Kishi, R.; Ito, A.; Kamada, K.; Fukita, T.; Lahrita, L.; Kawase, Y.; Murahashi, K.; Kawamata, H.; Naruse, N.; Takahashi, Y.

    2017-12-01

    Precise estimation of tree density in the forest leads us to understand the amount of carbon dioxide fixed by plants. Aerial photographs have been used to measure the number of trees. Campaign using aircraft, however, is expensive ( $50,000/1 campaign flight) and the research area is limited in drone. In addition, previous studies estimating the density of trees from aerial photographs have been performed in the summer, so there was a gap of 15% in the estimation due to the overlapping of the leaves. Here, we have proposed a method to accurately estimate the number of forest trees from the satellite images of snow-covered deciduous forest area, using the ratio of branches to snow. The advantages of our method are as follows; 1) snow area could be excluded easily due to the high reflectance, 2) tree branches are small overlapping compared to leaves. Although our method can use only in the snowfall region, the area covered with snow in the world becomes more than 12,800,000 km2. Our proposition should play an important role in discussing global warming. As a test area, we have chosen the forest near Mt. Amano in Iwate prefecture in Japan. First, we made a new index of (Band1-Band5)/(Band1+Band5), which will be suitable to distinguish between the snow and the tree trunk using the corresponding spectral reflection data. Next, the index values of changing the ratio in 1% increments were listed. From the satellite image analysis at 4 points, the ratio of snow to tree trunk showed the following values, I:61%, II:65%, III:66% and IV:65%. To confirm the estimation, we used the aerial photograph from Google earth; the rate was I:42.05%, II:48.89%, III:50.64%, IV:49.05%, respectively. There is a correlation between the numerical values of both, but there are differences. We will discuss in detail at this point, focusing on the effect of shadows.

  3. PIXE analysis of tree leaves as a possible comparative integral monitor of particulates in urban areas

    International Nuclear Information System (INIS)

    Zucchiati, A.; Annegarm, H.J.; Chisci, R.

    1988-01-01

    The possibility of obtaing integral comparative data for particulate distribution in urban areas from PIXE analysis of tree leaves is discussed in relation to the leaf gross anatomy, to the diffusion of selected tree species in such areas and to the implementation of experimental techniques necessary to make PIXE analysis effective. Multielemental scans were performed on a small set samples; results are compared to PIXE analysis of typical urban aerosols. The validity of the method and the criteria for yearly relative comparisons of different areas are discissed

  4. Scavenging capacity of strawberry tree (Arbutus unedo L.) leaves on free radicals.

    Science.gov (United States)

    Oliveira, Ivo; Coelho, Valentim; Baltasar, Raquel; Pereira, José Alberto; Baptista, Paula

    2009-07-01

    Despite strawberry tree (Arbutus unedo L.) leaves had a long use in traditional medicine due to its antiseptic, diuretic, astringent and depurative properties, the potential of their antioxidant activity are still lacking. Our study goals to assess the antioxidant and free radical scavenging potential of water, ethanol, methanol and diethyl ether extracts of A. unedo leaves. Total phenols content was achieved spectrophotometrically using Folin-Ciocalteau reagent with gallic acid as standard. Antioxidant activity was evaluated using three different methods: reducing power of iron (III)/ferricyanide complex assay, scavenging effect on DPPH (2,2-diphenyl-1-picrylhydrazyl) radicals and scavenging effect on superoxide radicals by using the PMS-NADH-nitroblue tetrazolium system. Ethanol extracts of A. unedo leaves were the highest in reducing power (IC(50) 232.7 microg/mL) and DPPH scavenging effect (IC(50) 63.2 microg/mL) followed by water extracts (with IC(50) of 287.7 and 73.7 microg/mL, respectively); whereas diethyl ether extracts were the lowest. In the scavenging on superoxide radical assay, methanol extracts obtained the best results (IC(50) 6.9 microg/mL). For all the methods tested the antioxidant activity was concentration dependent. In accordance with antioxidant activity, highest total phenols content were found in ethanol, followed by water, methanol and diethyl ether extract. The results indicated that A. unedo leaves are a potential source of natural antioxidants.

  5. Environmental fate of emamectin benzoate after tree micro injection of horse chestnut trees.

    Science.gov (United States)

    Burkhard, Rene; Binz, Heinz; Roux, Christian A; Brunner, Matthias; Ruesch, Othmar; Wyss, Peter

    2015-02-01

    Emamectin benzoate, an insecticide derived from the avermectin family of natural products, has a unique translocation behavior in trees when applied by tree micro injection (TMI), which can result in protection from insect pests (foliar and borers) for several years. Active ingredient imported into leaves was measured at the end of season in the fallen leaves of treated horse chestnut (Aesculus hippocastanum) trees. The dissipation of emamectin benzoate in these leaves seems to be biphasic and depends on the decomposition of the leaf. In compost piles, where decomposition of leaves was fastest, a cumulative emamectin benzoate degradation half-life time of 20 d was measured. In leaves immersed in water, where decomposition was much slower, the degradation half-life time was 94 d, and in leaves left on the ground in contact with soil, where decomposition was slowest, the degradation half-life time was 212 d. The biphasic decline and the correlation with leaf decomposition might be attributed to an extensive sorption of emamectin benzoate residues to leaf macromolecules. This may also explain why earthworms ingesting leaves from injected trees take up very little emamectin benzoate and excrete it with the feces. Furthermore, no emamectin benzoate was found in water containing decomposing leaves from injected trees. It is concluded, that emamectin benzoate present in abscised leaves from horse chestnut trees injected with the insecticide is not available to nontarget organisms present in soil or water bodies. Published 2014 SETAC.

  6. FITOSSOCIOLOGIA DE FRAGMENTOS DE FLORESTA ESTACIONAL DECIDUAL NO ESTADO DE SANTA CATARINA – BRASIL

    Directory of Open Access Journals (Sweden)

    Lauri Amândio Schorn

    2014-01-01

    Full Text Available This study aimed to evaluate the species composition and structure of Seasonal Deciduous Forest in the southern Brazilian state of Santa Catarina, including the tree/shrub component and the natural regeneration. We also compared the floristic composition between the components and discussed about the conservation condition of forests. The study was based on sample plots established by the Floristic and Forest Inventory of Santa Catarina state. Tree/shrub component was sampled by 78 plots placed systematically with 4,000 m² of sample area each, were individuals with DBH (diameter at breast height ≥ 10 cm was measured. Regeneration (DBH 1.50 m was sampled in subplots of 100 m² each. Structure and diversity of sample plots were analyzed in both components; species were classified by their ecologic group. To test the association between components was made a Non-metric Multidimensional Scaling (NMSD and Mantel test. We sampled 245 species, among them 215 in the tree/shrub component (79 of them exclusive, 165 species in the natural regeneration (30 exclusive ones and 136 species common to the two components. The association between components was confirmed with NMSD and Mantel test (r = 0.34; p = 0.001. Species with major importance value were mostly early secondary species that emphasizes the consequences of long term exploitation and degradation of Seasonal Deciduous Forest in Santa Catarina.

  7. Ecophysiology of the internal cycling of nitrogen in deciduous fruit trees

    International Nuclear Information System (INIS)

    Millard, P.

    2005-01-01

    In EU Countries, society’s expectations and political decisions have pushed the adoption of ecologically sustainable ways to manage orchards. Nitrogen (N) nutrition is a powerful means of controlling growth and fruiting of trees and guidelines for N management now aim to limit fertiliser applications below threshold values in order to reduce N losses. Increasing the effectiveness of the recycling of N pools available in the orchard is a basic step to reduce external N inputs. The availability of the stable isotope 15N as experimental tool has made possible significant advancements in the knowledge of the fluxes of N in the soil-tree system. Within-tree N sources for vegetative tree growth and reproduction include remobilization of winter stored N (within the tree and between the years) and root-shoot-root N recycling (within the tree and within each year). Nitrogen remobilization from storage is the major source of N in spring, until root uptake becomes predominant. As trees age, relatively more N in new growth is derived from storage and trees become relatively less dependent on root N uptake. Specific amino acids and amides have been identified in the xylem sap of several trees, including apple and cherry, that are considered responsible for remobilization of N compounds in spring. Most evidence has been obtained with relatively young trees grown in pot so there is a need for developing new approaches for quantifying N storage by adult trees in the field. Shoot-root transport of N and subsequent xylem reloading at the root level is a normal feature of vascular plants. While qualitative evidence of this phenomenon are based on detailed analysis of phloem and xylem sap, quantifying reloading N in the xylem was approached by comparing the N fluxes in the xylem with the accumulation of N in tree canopy. Results indicate that recycling of N in the xylem is a mechanism by which plants might regulate N uptake by roots. The adoption of stable isotope techniques in tree

  8. Water migration of macroelements in coniferous-broad-leaved forests of Sikhote-Alin

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    N. K. Kozhevnikova

    2017-06-01

    Full Text Available In the paper, the natural water chemical composition spatial variability studies results in the mountain forest catchment are presented. It’s shown that the catchment biotic components’ impact upon water chemical composition is detected even at input as atmospheric precipitation. The input fluxes are acid, sulfate ones with high ratio of hydrogen, potassium and dissolved organic matter. Diversity of ecotopic conditions determines the further transformation of natural water chemical composition. The role of tree crowns in the transformation increases while the crown closure and stands’ age increase. According to macrocomponents transformation and rain acidity neutralization, forest associations form the sequence: mixed > coniferous > young deciduous ones. Dissolved organic carbon (DOC, potassium and calcium become the main components of water chemical composition, while sulfates dominate among anions. For vegetation period, 9–11 kg/ha of sulfates come below tree crown. Biogenic elements transport is gradually limited in soil profile at the migration stage. Sulfate-potassium composition throughfall in spruce-fir and secondary forests community transforms into sulfate-sodium-calcium. Hydrocarbonates predominate in soil water in broad-leaved-pine type of forest, and potassium output decreases 10 times. Geochemical type of river water keeps features of chemical composition of soil drained by river section. Negligible output of sulfates, hydrocarbonates and calcium from ecosystem is established for the headwaters. Negative balance of hydrocarbonates and calcium is compensated by significant input of these components with throughfall at catchments with predominantly pine-broad-leaved forest types.

  9. The expression of light-related leaf functional traits depends on the location of individual leaves within the crown of isolated Olea europaea trees.

    Science.gov (United States)

    Escribano-Rocafort, Adrián G; Ventre-Lespiaucq, Agustina B; Granado-Yela, Carlos; Rubio de Casas, Rafael; Delgado, Juan A; Balaguer, Luis

    2016-04-01

    The spatial arrangement and expression of foliar syndromes within tree crowns can reflect the coupling between crown form and function in a given environment. Isolated trees subjected to high irradiance and concomitant stress may adjust leaf phenotypes to cope with environmental gradients that are heterogeneous in space and time within the tree crown. The distinct expression of leaf phenotypes among crown positions could lead to complementary patterns in light interception at the crown scale. We quantified eight light-related leaf traits across 12 crown positions of ten isolated Olea europaea trees in the field. Specifically, we investigated whether the phenotypic expression of foliar traits differed among crown sectors and layers and five periods of the day from sunrise to sunset. We investigated the consequences in terms of the exposed area of the leaves at the tree scale during a single day. All traits differed among crown positions except the length-to-width ratio of the leaves. We found a strong complementarity in the patterns of the potential exposed area of the leaves among day periods as a result of a non-random distribution of leaf angles across the crown. Leaf exposure at the outer layer was below 60 % of the displayed surface, reaching maximum interception during morning periods. Daily interception increased towards the inner layer, achieving consecutive maximization from east to west positions within the crown, matching the sun's trajectory. The expression of leaf traits within isolated trees of O. europaea varies continuously through the crown in a gradient of leaf morphotypes and leaf angles depending on the exposure and location of individual leaves. The distribution of light-related traits within the crown and the complementarity in the potential exposure patterns of the leaves during the day challenges the assumption of low trait variability within individuals. © The Author 2016. Published by Oxford University Press on behalf of the Annals of

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

    Science.gov (United States)

    Barbeta, Adrià; Peñuelas, Josep

    2017-12-01

    Tree populations at the low-altitudinal or -latitudinal limits of species' distributional ranges are predicted to retreat toward higher altitudes and latitudes to track the ongoing changes in climate. Studies have focused on the climatic sensitivity of the retreating species, whereas little is known about the potential replacements. Competition between tree species in forest ecotones will likely be strongly influenced by the ecophysiological responses to heat and drought. We used tree-ring widths and δ 13 C and δ 18 O chronologies to compare the growth rates and long-term ecophysiological responses to climate in the temperate-Mediterranean ecotone formed by the deciduous Fagus sylvatica and the evergreen Quercus ilex at the low altitudinal and southern latitudinal limit of F. sylvatica (NE Iberian Peninsula). F. sylvatica growth rates were similar to those of other southern populations and were surprisingly not higher than those of Q. ilex, which were an order of magnitude higher than those in nearby drier sites. Higher Q. ilex growth rates were associated with high temperatures, which have increased carbon discrimination rates in the last 25 years. In contrast, stomatal regulation in F. sylvatica was proportional to the increase in atmospheric CO 2 . Tree-ring δ 18 O for both species were mostly correlated with δ 18 O in the source water. In contrast to many previous studies, relative humidity was not negatively correlated with tree-ring δ 18 O but had a positive effect on Q. ilex tree-ring δ 18 O. Furthermore, tree-ring δ 18 O decreased in Q. ilex over time. The sensitivity of Q. ilex to climate likely reflects the uptake of deep water that allowed it to benefit from the effect of CO 2 fertilization, in contrast to the water-limited F. sylvatica. Consequently, Q. ilex is a strong competitor at sites currently dominated by F. sylvatica and could be favored by increasingly warmer conditions. © 2017 John Wiley & Sons Ltd.

  11. Human decidual stromal cells secrete soluble pro-apoptotic factors during decidualization in a cAMP-dependent manner.

    Science.gov (United States)

    Leno-Durán, E; Ruiz-Magaña, M J; Muñoz-Fernández, R; Requena, F; Olivares, E G; Ruiz-Ruiz, C

    2014-10-10

    Is there a relationship between decidualization and apoptosis of decidual stromal cells (DSC)? Decidualization triggers the secretion of soluble factors that induce apoptosis in DSC. The differentiation and apoptosis of DSC during decidualization of the receptive decidua are crucial processes for the controlled invasion of trophoblasts in normal pregnancy. Most DSC regress in a time-dependent manner, and their removal is important to provide space for the embryo to grow. However, the mechanism that controls DSC death is poorly understood. The apoptotic response of DSC was analyzed after exposure to different exogenous agents and during decidualization. The apoptotic potential of decidualized DSC supernatants and prolactin (PRL) was also evaluated. DSC lines were established from samples of decidua from first trimester pregnancies. Apoptosis was assayed by flow cytometry. PRL production, as a marker of decidualization, was determined by enzyme-linked immunosorbent assay. DSCs were resistant to a variety of apoptosis-inducing substances. Nevertheless, DSC underwent apoptosis during decidualization in culture, with cAMP being essential for both apoptosis and differentiation. In addition, culture supernatants from decidualized DSC induced apoptosis in undifferentiated DSC, although paradoxically these supernatants decreased the spontaneous apoptosis of decidual lymphocytes. Exogenously added PRL did not induce apoptosis in DSC and an antibody that neutralized the PRL receptor did not decrease the apoptosis induced by supernatants. Further studies are needed to examine the involvement of other soluble factors secreted by decidualized DSC in the induction of apoptosis. The present results indicate that apoptosis of DSC occurs in parallel to differentiation, in response to decidualization signals, with soluble factors secreted by decidualized DSC being responsible for triggering cell death. These studies are relevant in the understanding of how the regression of decidua

  12. Assessing atmospheric particulate matter distribution based on Saturation Isothermal Remanent Magnetization of herbaceous and tree leaves in a tropical urban environment.

    Science.gov (United States)

    Barima, Yao Sadaiou Sabas; Angaman, Djédoux Maxime; N'gouran, Kobenan Pierre; Koffi, N'guessan Achille; Kardel, Fatemeh; De Cannière, Charles; Samson, Roeland

    2014-02-01

    Particulate matter (PM) emissions, and the associated human health risks, are likely to continue increasing in urban environments of developing countries like Abidjan (Ivory Cost). This study evaluated the potential of leaves of several herbaceous and tree species as bioindicators of urban particulate matter pollution, and its variation over different land use classes, in a tropical area. Four species well distributed (presence frequencies >90%) over all land use classes, easy to harvest and whose leaves are wide enough to be easily scanned were selected, i.e.: Amaranthus spinosus (Amaranthaceae), Eleusine indica (Poaceae), Panicum maximum (Poaceae) and Ficus benjamina (Moraceae). Leaf sampling of these species was carried out at 3 distances from the road and at 3 height levels. Traffic density was also noted and finally biomagnetic parameters of these leaves were determined. Results showed that Saturation Isothermal Remanent Magnetization (SIRM) of leaves was at least 4 times higher (27.5×10(-6)A) in the vicinity of main roads and industrial areas than in parks and residential areas. The main potential sources of PM pollution were motor vehicles and industries. The slightly hairy leaves of the herbaceous plant A. spinosus and the waxy leaves of the tree F. benjamina showed the highest SIRM (25×10(-6)A). Leaf SIRM increased with distance to road (R(2)>0.40) and declined with sampling height (R(2)=0.17). The distance between 0 and 5m from the road seemed to be the most vulnerable in terms of PM pollution. This study has showed that leaf SIRM of herbaceous and tree species can be used to assess PM exposure in tropical urban environments. © 2013.

  13. Desert Southwest Community Tree Guide: Benefits, Costs and Strategic Planting

    Science.gov (United States)

    Greg McPherson; J.R. Simpson; P.J. Peper; S.E. Maco; Q. Xiao; E. Mulrean

    2004-01-01

    This report quantifies benefits and costs for typical large-, medium-, small-stature, deciduous trees (Fraxinus uhdei, Prosopis chilensis, Acacia farnesiana), as well as a conifer (Pinus halapensis). The analysis assumed that trees were planted in a residential yard site or a public (street/park) site, a 40-year time frame, and...

  14. Uranium mobility across annual growth rings in three deciduous tree species.

    Science.gov (United States)

    McHugh, Kelly C; Widom, Elisabeth; Spitz, Henry B; Wiles, Gregory C; Glover, Sam E

    2018-02-01

    Black walnut (Juglans nigra), slippery elm (Ulmus rubra), and white ash (Fraxinus americana) trees were evaluated as potential archives of past uranium (U) contamination. Like other metals, U mobility in annual growth rings of trees is dependent on the tree species. Uranium concentrations and isotopic compositions (masses 234, 235, 236, and 238) were analyzed by thermal ionization mass spectrometry to test the efficacy of using tree rings to retroactively monitor U pollution from the FFMPC, a U purification facility operating from 1951 to 1989. This study found non-natural U (depleted U and detectable 236 U) in growth rings of all three tree species that pre-dated the start of operations at FFMPC and compositional trends that did not correspond with known contamination events. Therefore, the annual growth rings of these tree species cannot be used to reliably monitor the chronology of U contamination. Copyright © 2017 Elsevier Ltd. All rights reserved.

  15. Decidual-secreted factors alter invasive trophoblast membrane and secreted proteins implying a role for decidual cell regulation of placentation.

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    Ellen Melaleuca Menkhorst

    Full Text Available Inadequate or inappropriate implantation and placentation during the establishment of human pregnancy is thought to lead to first trimester miscarriage, placental insufficiency and other obstetric complications. To create the placental blood supply, specialized cells, the 'extravillous trophoblast' (EVT invade through the differentiated uterine endometrium (the decidua to engraft and remodel uterine spiral arteries. We hypothesized that decidual factors would regulate EVT function by altering the production of EVT membrane and secreted factors. We used a proteomics approach to identify EVT membrane and secreted proteins regulated by decidual cell factors. Human endometrial stromal cells were decidualized in vitro by treatment with estradiol (10(-8 M, medroxyprogesterone acetate (10(-7 M and cAMP (0.5 mM for 14 days. Conditioned media (CM was collected on day 2 (non-decidualized CM and 14 (decidualized CM of treatment. Isolated primary EVT cultured on Matrigel™ were treated with media control, non-decidualized or decidualized CM for 16 h. EVT CM was fractionated for proteins <30 kDa using size-exclusion affinity nanoparticles (SEAN before trypsin digestion and HPLC-MS/MS. 43 proteins produced by EVT were identified; 14 not previously known to be expressed in the placenta and 12 which had previously been associated with diseases of pregnancy including preeclampsia. Profilin 1, lysosome associated membrane glycoprotein 1 (LAMP1, dipeptidyl peptidase 1 (DPP1/cathepsin C and annexin A2 expression by interstitial EVT in vivo was validated by immunhistochemistry. Decidual CM regulation in vitro was validated by western blotting: decidualized CM upregulated profilin 1 in EVT CM and non-decidualized CM upregulated annexin A2 in EVT CM and pro-DPP1 in EVT cell lysate. Here, non-decidualized factors induced protease expression by EVT suggesting that non-decidualized factors may induce a pro-inflammatory cascade. Preeclampsia is a pro

  16. Interspecific variation in leaf pigments and nutrients of five tree species from a subtropical forest in southern Brazil

    Directory of Open Access Journals (Sweden)

    MÁRCIA BÜNDCHEN

    2016-01-01

    Full Text Available ABSTRACT The purpose of this study was to analyze the seasonal variation in the nutrient and pigment content of leaves from five tree species - of which three are perennial (Cupania vernalis, Matayba elaeagnoides and Nectandra lanceolata and two are deciduous (Cedrela fissilis and Jacaranda micrantha - in an ecotone between a Deciduous Seasonal Forest and a Mixed Ombrophilous Forest in the state of Santa Catarina, Brazil. Leaf samples were collected in the four seasons of the year to determine the content of macronutrients (N, K, P, Mg, Ca, S and photosynthetic pigments (Chla, Chlb, Chltot, Cartot, Chla:Chlb and Cartot:Chltot. The principal component analysis showed that leaf pigments contributed to the formation of the first axis, which explains most of the data variance for all species, while leaf nutrient contribution showed strong interspecific variation. These results demonstrate that the studied species have different strategies for acquisition and use of mineral resources and acclimation to light, which are determinant for them to coexist in the forest environment.

  17. Interspecific variation in tree seedlings establishment in canopy gaps in relation to tree density

    Energy Technology Data Exchange (ETDEWEB)

    Reader, R.J.; Bonser, S.P.; Duralia, T.E.; Bricker, B.D. [Guelph Univ., ON (Canada). Dept. of Botany

    1995-10-01

    We tested whether interspecific variation in tree seedling establishment in canopy gaps was significantly related to interspecific variation in tree density, for seven deciduous forest tree species (Quercus alba, Hamamelis virginiana, Acer rubrum, Sassafras albidum, Quercus rubra, Prunus serotina, Ostrya virginiana). For each species, seedling establishment was calculated as the difference in seedling density before experimental gap creation versus three years after gap creation. In each of the six experimentally-created gap types (33% or 66% removal of tree basal area from 0.01ha, 0.05ha or 0.20ha patches), differences in seedling establishment among species were significantly related to differences in their density in the tree canopy. A regression model with log{sub e} tree density as the independent variable accounted for between 93% and 98% of interspecific variation in seedling establishment. Our results provide empirical support for models of tree dynamics in gaps that assume seedling establishment depends on canopy tree density. 17 refs, 1 fig, 3 tabs

  18. Enhancement of understory productivity by asynchronous phenology with overstory competitors in a temperate deciduous forest.

    Science.gov (United States)

    Jolly, William M; Nemani, Ramakrishna; Running, Steven W

    2004-09-01

    Some saplings and shrubs growing in the understory of temperate deciduous forests extend their periods of leaf display beyond that of the overstory, resulting in periods when understory radiation, and hence productivity, are not limited by the overstory canopy. To assess the importance of the duration of leaf display on the productivity of understory and overstory trees of deciduous forests in the north eastern United States, we applied the simulation model, BIOME-BGC with climate data for Hubbard Brook Experimental Forest, New Hampshire, USA and mean ecophysiological data for species of deciduous, temperate forests. Extension of the overstory leaf display period increased overstory leaf area index (LAI) by only 3 to 4% and productivity by only 2 to 4%. In contrast, extending the growing season of the understory relative to the overstory by one week in both spring and fall, increased understory LAI by 35% and productivity by 32%. A 2-week extension of the growing period in both spring and fall increased understory LAI by 53% and productivity by 55%.

  19. Environmental Fate of Emamectin Benzoate After Tree Micro Injection of Horse Chestnut Trees

    OpenAIRE

    Burkhard, Rene; Binz, Heinz; Roux, Christian A; Brunner, Matthias; Ruesch, Othmar; Wyss, Peter

    2014-01-01

    Emamectin benzoate, an insecticide derived from the avermectin family of natural products, has a unique translocation behavior in trees when applied by tree micro injection (TMI), which can result in protection from insect pests (foliar and borers) for several years. Active ingredient imported into leaves was measured at the end of season in the fallen leaves of treated horse chestnut (Aesculus hippocastanum) trees. The dissipation of emamectin benzoate in these leaves seems to be biphasic an...

  20. Trends in Spring Phenology of Western European Deciduous Forests

    Directory of Open Access Journals (Sweden)

    Eliakim Hamunyela

    2013-11-01

    Full Text Available Plant phenology is changing because of recent global warming, and this change may precipitate changes in animal distribution (e.g., pests, alter the synchronization between species, and have feedback effects on the climate system through the alteration of biogeochemical and physical processes of vegetated land surface. Here, ground observations (leaf unfolding/first leaf separation of six deciduous tree species and satellite-derived start-of-growing season (SOS are used to assess how the timing of leafing/SOS in Western European deciduous forest responded to climate variability between 2001 and 2011 and evaluate the reliability of satellite SOS estimates in tracking the response of forest leafing to climate variability in this area. Satellite SOS estimates are derived from the Normalized Difference Vegetation Index (NDVI time series of the Moderate Resolution Imaging Spectroradiometer (MODIS. Temporal trends in the SOS are quantified using linear regression, expressing SOS as a function of time. We demonstrated that the growing season was starting earlier between 2001 and 2011 for the majority of temperate deciduous forests in Western Europe, possibly influenced by regional spring warming effects experienced during the same period. A significant shift of up to 3 weeks to early leafing was found in both ground observations and satellite SOS estimates. We also show that the magnitude and trajectory of shifts in satellite SOS estimates are well comparable to that of in situ observations, hence highlighting the importance of satellite imagery in monitoring leaf phenology under a changing climate.

  1. Soil nematode community under the non-native trees in the Botanic Garden of Petrozavodsk State University

    Directory of Open Access Journals (Sweden)

    Sushchuk Anna

    2016-12-01

    Full Text Available The particularities of soil nematode communities of the rhizosphere of non-native trees were studied in the Botanic Garden of Petrozavodsk State University (Republic of Karelia. Taxonomic diversity, abundance, community structure and ecological indices derived from nematode fauna analysis were used as the evaluation parameters. Nematode fauna included 51 genera, 6 of them were plant parasitic. The dominant eco-trophic group in the nematode community structure of coniferous trees was bacterial feeders; fungal feeders in most cases were observed in the second numbers. The contribution of bacterial feeders was decreased and plant parasites were increased in eco-trophic structure of nematode communities of deciduous trees in compared with coniferous trees. Analysis of ecological indices showed that the state of soil nematode communities reflects complex, structured (stable soil food web in the biocenoses with deciduous trees, and degraded (basal food web – under coniferous trees.

  2. Urban trees reduce nutrient leaching to groundwater.

    Science.gov (United States)

    Nidzgorski, Daniel A; Hobbie, Sarah E

    2016-07-01

    Many urban waterways suffer from excess nitrogen (N) and phosphorus (P), feeding algal blooms, which cause lower water clarity and oxygen levels, bad odor and taste, and the loss of desirable species. Nutrient movement from land to water is likely to be influenced by urban vegetation, but there are few empirical studies addressing this. In this study, we examined whether or not urban trees can reduce nutrient leaching to groundwater, an important nutrient export pathway that has received less attention than stormwater. We characterized leaching beneath 33 trees of 14 species, and seven open turfgrass areas, across three city parks in Saint Paul, Minnesota, USA. We installed lysimeters at 60 cm depth to collect soil water approximately biweekly from July 2011 through October 2013, except during winter and drought periods, measured dissolved organic carbon (C), N, and P in soil water, and modeled water fluxes using the BROOK90 hydrologic model. We also measured soil nutrient pools (bulk C and N, KCl-extractable inorganic N, Brays-P), tree tissue nutrient concentrations (C, N, and P of green leaves, leaf litter, and roots), and canopy size parameters (leaf biomass, leaf area index) to explore correlations with nutrient leaching. Trees had similar or lower N leaching than turfgrass in 2012 but higher N leaching in 2013; trees reduced P leaching compared with turfgrass in both 2012 and 2013, with lower leaching under deciduous than evergreen trees. Scaling up our measurements to an urban subwatershed of the Mississippi River (~17 400 ha, containing ~1.5 million trees), we estimated that trees reduced P leaching to groundwater by 533 kg in 2012 (0.031 kg/ha or 3.1 kg/km 2 ) and 1201 kg in 2013 (0.069 kg/ha or 6.9 kg/km 2 ). Removing these same amounts of P using stormwater infrastructure would cost $2.2 million and $5.0 million per year (2012 and 2013 removal amounts, respectively). © 2016 by the Ecological Society of America.

  3. Intra- and interspecific variation in tropical tree and liana phenology derived from Unmanned Aerial Vehicle images

    Science.gov (United States)

    Bohlman, S.; Park, J.; Muller-Landau, H. C.; Rifai, S. W.; Dandois, J. P.

    2017-12-01

    Phenology is a critical driver of ecosystem processes. There is strong evidence that phenology is shifting in temperate ecosystems in response to climate change, but tropical tree and liana phenology remains poorly quantified and understood. A key challenge is that tropical forests contain hundreds of plant species with a wide variety of phenological patterns. Satellite-based observations, an important source of phenology data in northern latitudes, are hindered by frequent cloud cover in the tropics. To quantify phenology over a large number of individuals and species, we collected bi-weekly images from unmanned aerial vehicles (UAVs) in the well-studied 50-ha forest inventory plot on Barro Colorado Island, Panama. Between October 2014 and December 2015 and again in May 2015, we collected a total of 35 sets of UAV images, each with continuous coverage of the 50-ha plot, where every tree ≥ 1 cm DBH is mapped. Spectral, texture, and image information was extracted from the UAV images for individual tree crowns, which was then used as inputs for a machine learning algorithm to predict percent leaf and branch cover. We obtained the species identities of 2000 crowns in the images via field mapping. The objectives of this study are to (1) determined if machine learning algorithms, applied to UAV images, can effectively quantify changes in leaf cover, which we term "deciduousness; (2) determine how liana cover effects deciduousness and (3) test how well UAV-derived deciduousness patterns match satellite-derived temporal patterns. Machine learning algorithms trained on a variety of image parameters could effectively determine leaf cover, despite variation in lighting and viewing angles. Crowns with higher liana cover have less overall deciduousness (tree + liana together) than crowns with lower liana cover. Individual crown deciduousness, summed over all crowns measured in the 50-ha plot, showed a similar seasonal pattern as MODIS EVI composited over 10 years. However

  4. Within-twig leaf distribution patterns differ among plant life-forms in a subtropical Chinese forest.

    Science.gov (United States)

    Meng, Fengqun; Cao, Rui; Yang, Dongmei; Niklas, Karl J; Sun, Shucun

    2013-07-01

    In theory, plants can alter the distribution of leaves along the lengths of their twigs (i.e., within-twig leaf distribution patterns) to optimize light interception in the context of the architectures of their leaves, branches and canopies. We hypothesized that (i) among canopy tree species sharing similar light environments, deciduous trees will have more evenly spaced within-twig leaf distribution patterns compared with evergreen trees (because deciduous species tend to higher metabolic demands than evergreen species and hence require more light), and that (ii) shade-adapted evergreen species will have more evenly spaced patterns compared with sun-adapted evergreen ones (because shade-adapted species are generally light-limited). We tested these hypotheses by measuring morphological traits (i.e., internode length, leaf area, lamina mass per area, LMA; and leaf and twig inclination angles to the horizontal) and physiological traits (i.e., light-saturated net photosynthetic rates, Amax; light saturation points, LSP; and light compensation points, LCP), and calculated the 'evenness' of within-twig leaf distribution patterns as the coefficient of variation (CV; the higher the CV, the less evenly spaced leaves) of within-twig internode length for 9 deciduous canopy tree species, 15 evergreen canopy tree species, 8 shade-adapted evergreen shrub species and 12 sun-adapted evergreen shrub species in a subtropical broad-leaved rainforest in eastern China. Coefficient of variation was positively correlated with large LMA and large leaf and twig inclination angles, which collectively specify a typical trait combination adaptive to low light interception, as indicated by both ordinary regression and phylogenetic generalized least squares analyses. These relationships were also valid within the evergreen tree species group (which had the largest sample size). Consistent with our hypothesis, in the canopy layer, deciduous species (which were characterized by high LCP, LSP and

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

    Science.gov (United States)

    Gandhi, Durai Sanjay; Sundarapandian, Somaiah

    2017-04-01

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

  6. Synthesis on the carbon budget and cycling in a Danish, temperate deciduous forest

    DEFF Research Database (Denmark)

    Wu, Jian; Larsen, Klaus Steenberg; van der Linden, Leon

    2013-01-01

    A synthesis of five years (2006–2010) of data on carbon cycling in a temperate deciduous forest, Sorø (Zealand, Denmark) was performed by combining all available data from eddy covariance, chamber, suction cups, and biometric measurements. The net ecosystem exchange of CO2 (NEE), soil respiration...... within the ecosystem. The results showed that this temperate deciduous forest was a moderate carbon sink (258±41gCm−2 yr−1) with both high rates of gross primary production (GPP, 1881±95gCm−2 yr−1) and ecosystem respiration (Re, 1624±197gCm−2 yr−1). Approximately 62% of the gross assimilated carbon......, tree growth, litter production and leaching of dissolved inorganic and organic carbon were independently estimated and used to calculate other unmeasured ecosystem carbon budget (ECB) components, based on mass balance equations. This provided a complete assessment of the carbon storage and allocation...

  7. Albizzia lebbeck Benth. (Hindi: Siris) of Leguminosae is a large ...

    Indian Academy of Sciences (India)

    Albizzia lebbeck Benth. (Hindi: Siris) of Leguminosae is a large deciduous tree with greyish bark and compound leaves. Flowers are greenish-yellow in head inflorescences. Fruit pods are yellowish-brown, flat and carry 6-10 seeds (Inset shows the entire crown of the tree covered with previous season's dry pods).

  8. Effect of tree logging on reproductive performance in Blue Tits (Cyanistes caeruleus)

    OpenAIRE

    Amininasab, Seyed Mehdi; Xu, Charles C. Y.; Kingma, Sjouke A.; Komdeur, Jan

    2017-01-01

    For birds, habitat quality is largely determined by local vegetation, and reproductive performance can therefore be negatively influenced by anthropogenic activities. A tree logging event enabled us to examine the effect of removing trees of different maturities and types on the reproductive performance of Blue Tits (Cyanistes caeruleus). Against expectations, only the logging of small coniferous trees, but not larger and deciduous trees, was associated with a reduction in the number of eggs ...

  9. Sub-pixel estimation of tree cover and bare surface densities using regression tree analysis

    Directory of Open Access Journals (Sweden)

    Carlos Augusto Zangrando Toneli

    2011-09-01

    Full Text Available Sub-pixel analysis is capable of generating continuous fields, which represent the spatial variability of certain thematic classes. The aim of this work was to develop numerical models to represent the variability of tree cover and bare surfaces within the study area. This research was conducted in the riparian buffer within a watershed of the São Francisco River in the North of Minas Gerais, Brazil. IKONOS and Landsat TM imagery were used with the GUIDE algorithm to construct the models. The results were two index images derived with regression trees for the entire study area, one representing tree cover and the other representing bare surface. The use of non-parametric and non-linear regression tree models presented satisfactory results to characterize wetland, deciduous and savanna patterns of forest formation.

  10. Development of Envelope Curves for Predicting Void Dimensions from Overturned Trees

    Science.gov (United States)

    2014-07-01

    Engineers Washington , DC 20314-1000 ERDC/GSL TR-14-27 ii Abstract To evaluate the potential influence of a tree on embankment stability, it is...4.5 Consistent influence of tree diameter and species on damage in nine eastern North America tornado blowdowns (Peterson 2007...likely to be blown down than deciduous trees . Phillips et al. (2008) independently came to the same conclusion that conifers have a higher

  11. A bijection between phylogenetic trees and plane oriented recursive trees

    OpenAIRE

    Prodinger, Helmut

    2017-01-01

    Phylogenetic trees are binary nonplanar trees with labelled leaves, and plane oriented recursive trees are planar trees with an increasing labelling. Both families are enumerated by double factorials. A bijection is constructed, using the respective representations a 2-partitions and trapezoidal words.

  12. Light-dependent leaf trait variation in 43 tropical dry forest tree species

    NARCIS (Netherlands)

    Markesteijn, L.; Poorter, L.; Bongers, F.J.J.M.

    2007-01-01

    Our understanding of leaf acclimation in relation to irradiance of fully grown or juvenile trees is mainly based on research involving tropical wet forest species. We studied sun¿shade plasticity of 24 leaf traits of 43 tree species in a Bolivian dry deciduous forest. Sampling was confined to small

  13. Trace Element Concentrations in Tree Leaves and Lichen Collected Along a Metal Pollution Gradient Near Olkusz (Southern Poland).

    Science.gov (United States)

    Zakrzewska, Marta; Klimek, Beata

    2018-02-01

    The aim of the study was to assess the metal pollution in the vicinity of the Bukowno smelter near Olkusz in southern Poland. Birch and oak leaves, pine needles and a lichen Hypogymnia physodes, overgrowing pine bark were collected at stands at different distances from the smelter and analysed for cadmium (Cd), copper (Cu), lead (Pb) and zinc (Zn) content. Concentrations of metals in the lichen were usually higher than in the tree leaves/needles and decreased with distance from the smelter, apart from the Cu content. The strongest correlation was noticed between Cd and Pb concentrations, which indicates a common pollution source (the smelter). Our results show that birch leaves can be potentially useful as a bioindicator of Zn air pollution since this species was shown to accumulate high amounts of zinc, related to environmental pollution with that metal, in their leaves.

  14. Application of plant DNA markers in forensic botany: genetic comparison of Quercus evidence leaves to crime scene trees using microsatellites.

    Science.gov (United States)

    Craft, Kathleen J; Owens, Jeffrey D; Ashley, Mary V

    2007-01-05

    As highly polymorphic DNA markers become increasingly available for a wide range of plant and animal species, there will be increasing opportunities for applications to forensic investigations. To date, however, relatively few studies have reported using DNA profiles of non-human species to place suspects at or near crime scenes. Here we describe an investigation of a double homicide of a female and her near-term fetus. Leaf material taken from a suspect's vehicle was identified to be that of sand live oak, Quercus geminata, the same tree species that occurred near a shallow grave where the victims were found. Quercus-specific DNA microsatellites were used to genotype both dried and fresh material from trees located near the burial site and from the material taken from the suspect's car. Samples from the local population of Q. geminata were also collected and genotyped in order to demonstrate that genetic variation at four microsatellite loci was sufficient to assign leaves to an individual tree with high statistical certainty. The cumulative average probability of identity for these four loci was 2.06x10(-6). DNA was successfully obtained from the dried leaf material although PCR amplification was more difficult than amplification of DNA from fresh leaves. The DNA profiles of the dried leaves from the suspect's car did not match those of the trees near the crime scene. Although this investigation did not provide evidence that could be used against the suspect, it does demonstrate the potential for plant microsatellite markers providing physical evidence that links plant materials to live plants at or near crime scenes.

  15. Decidual cell polyploidization necessitates mitochondrial activity.

    Directory of Open Access Journals (Sweden)

    Xinghong Ma

    Full Text Available Cellular polyploidy has been widely reported in nature, yet its developmental mechanism and function remain poorly understood. In the present study, to better define the aspects of decidual cell polyploidy, we isolated pure polyploid and non-polyploid decidual cell populations from the in vivo decidual bed. Three independent RNA pools prepared for each population were then subjected to the Affymetrix gene chip analysis for the whole mouse genome transcripts. Our data revealed up-regulation of 1015 genes and down-regulation of 1207 genes in the polyploid populations, as compared to the non-polyploid group. Comparative RT-PCR and in situ hybridization results indeed confirmed differential expressional regulation of several genes between the two populations. Based on functional enrichment analyses, up-regulated polyploidy genes appeared to implicate several functions, which primarily include cell/nuclear division, ATP binding, metabolic process, and mitochondrial activity, whereas that of down-regulated genes primarily included apoptosis and immune processes. Further analyses of genes that are related to mitochondria and bi-nucleation showed differential and regional expression within the decidual bed, consistent with the pattern of polyploidy. Consistently, studies revealed a marked induction of mitochondrial mass and ATP production in polyploid cells. The inhibition of mitochondrial activity by various pharmacological inhibitors, as well as by gene-specific targeting using siRNA-mediated technology showed a dramatic attenuation of polyploidy and bi-nucleation development during in vitro stromal cell decidualization, suggesting mitochondria play a major role in positive regulation of decidual cell polyploidization. Collectively, analyses of unique polyploidy markers and molecular signaling networks may be useful to further characterize functional aspects of decidual cell polyploidy at the site of implantation.

  16. Analytical method for the evaluation of the outdoor air contamination by emerging pollutants using tree leaves as bioindicators.

    Science.gov (United States)

    Barroso, Pedro José; Martín, Julia; Santos, Juan Luis; Aparicio, Irene; Alonso, Esteban

    2018-01-01

    In this work, an analytical method, based on sonication-assisted extraction, clean-up by dispersive solid-phase extraction and determination by liquid chromatography-tandem mass spectrometry, has been developed and validated for the simultaneous determination of 15 emerging pollutants in leaves from four ornamental tree species. Target compounds include perfluorinated organic compounds, plasticizers, surfactants, brominated flame retardant, and preservatives. The method was optimized using Box-Behnken statistical experimental design with response surface methodology and validated in terms of recovery, accuracy, precision, and method detection and quantification limits. Quantification of target compounds was carried out using matrix-matched calibration curves. The highest recoveries were achieved for the perfluorinated organic compounds (mean values up to 87%) and preservatives (up to 88%). The lowest recoveries were achieved for plasticizers (51%) and brominated flame retardant (63%). Method detection and quantification limits were in the ranges 0.01-0.09 ng/g dry matter (dm) and 0.02-0.30 ng/g dm, respectively, for most of the target compounds. The method was successfully applied to the determination of the target compounds on leaves from four tree species used as urban ornamental trees (Citrus aurantium, Celtis australis, Platanus hispanica, and Jacaranda mimosifolia). Graphical abstract Analytical method for the biomonitorization of emerging pollutants in outdoor air.

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

    International Nuclear Information System (INIS)

    Calatayud, Vicent; Cervero, Julia; Calvo, Esperanza; Garcia-Breijo, Francisco-Jose; Reig-Arminana, Jose; Sanz, Maria Jose

    2011-01-01

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

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2011-01-15

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

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

    Directory of Open Access Journals (Sweden)

    Azita Ahmad Zawawi

    2015-04-01

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

  20. Chemometrics in biomonitoring: Distribution and correlation of trace elements in tree leaves

    International Nuclear Information System (INIS)

    Deljanin, Isidora; Antanasijević, Davor; Bjelajac, Anđelika; Urošević, Mira Aničić; Nikolić, Miroslav; Perić-Grujić, Aleksandra; Ristić, Mirjana

    2016-01-01

    The concentrations of 15 elements were measured in the leaf samples of Aesculus hippocastanum, Tilia spp., Betula pendula and Acer platanoides collected in May and September of 2014 from four different locations in Belgrade, Serbia. The objective was to assess the chemical characterization of leaf surface and in-wax fractions, as well as the leaf tissue element content, by analyzing untreated, washed with water and washed with chloroform leaf samples, respectively. The combined approach of self-organizing networks (SON) and Preference Ranking Organization Method for Enrichment Evaluation (PROMETHEE) aided by Geometrical Analysis for Interactive Aid (GAIA) was used in the interpretation of multiple element loads on/in the tree leaves. The morphological characteristics of the leaf surfaces and the elemental composition of particulate matter (PM) deposited on tree leaves were studied by using scanning electron microscopy (SEM) with energy dispersive spectroscopy (EDS) detector. The results showed that the amounts of retained and accumulated element concentrations depend on several parameters, such as chemical properties of the element and morphological properties of the leaves. Among the studied species, Tilia spp. was found to be the most effective in the accumulation of elements in leaf tissue (70% of the total element concentration), while A. hippocastanum had the lowest accumulation (54%). After water and chloroform washing, the highest percentages of removal were observed for Al, V, Cr, Cu, Zn, As, Cd and Sb (> 40%). The PROMETHEE/SON ranking/classifying results were in accordance with the results obtained from the GAIA clustering techniques. The combination of the techniques enabled extraction of additional information from datasets. Therefore, the use of both the ranking and clustering methods could be a useful tool to be applied in biomonitoring studies of trace elements. - Highlights: • Surface and in-wax fractions showed different trace element

  1. Chemometrics in biomonitoring: Distribution and correlation of trace elements in tree leaves

    Energy Technology Data Exchange (ETDEWEB)

    Deljanin, Isidora [Innovation Center of the Faculty of Technology and Metallurgy, Karnegijeva 4, 11120 Belgrade, Serbia, (Serbia); Antanasijević, Davor, E-mail: dantanasijevic@tmf.bg.ac.rs [Innovation Center of the Faculty of Technology and Metallurgy, Karnegijeva 4, 11120 Belgrade, Serbia, (Serbia); Bjelajac, Anđelika [Innovation Center of the Faculty of Technology and Metallurgy, Karnegijeva 4, 11120 Belgrade, Serbia, (Serbia); Urošević, Mira Aničić [Institute of Physics, University of Belgrade, Pregrevica 118, 11080 Belgrade, Serbia, (Serbia); Nikolić, Miroslav [Institute for Multidisciplinary Research, University of Belgrade, Kneza Viseslava 1, 11030 Belgrade (Serbia); Perić-Grujić, Aleksandra; Ristić, Mirjana [University of Belgrade, Faculty of Technology and Metallurgy, Karnegijeva 4, 11120 Belgrade (Serbia)

    2016-03-01

    The concentrations of 15 elements were measured in the leaf samples of Aesculus hippocastanum, Tilia spp., Betula pendula and Acer platanoides collected in May and September of 2014 from four different locations in Belgrade, Serbia. The objective was to assess the chemical characterization of leaf surface and in-wax fractions, as well as the leaf tissue element content, by analyzing untreated, washed with water and washed with chloroform leaf samples, respectively. The combined approach of self-organizing networks (SON) and Preference Ranking Organization Method for Enrichment Evaluation (PROMETHEE) aided by Geometrical Analysis for Interactive Aid (GAIA) was used in the interpretation of multiple element loads on/in the tree leaves. The morphological characteristics of the leaf surfaces and the elemental composition of particulate matter (PM) deposited on tree leaves were studied by using scanning electron microscopy (SEM) with energy dispersive spectroscopy (EDS) detector. The results showed that the amounts of retained and accumulated element concentrations depend on several parameters, such as chemical properties of the element and morphological properties of the leaves. Among the studied species, Tilia spp. was found to be the most effective in the accumulation of elements in leaf tissue (70% of the total element concentration), while A. hippocastanum had the lowest accumulation (54%). After water and chloroform washing, the highest percentages of removal were observed for Al, V, Cr, Cu, Zn, As, Cd and Sb (> 40%). The PROMETHEE/SON ranking/classifying results were in accordance with the results obtained from the GAIA clustering techniques. The combination of the techniques enabled extraction of additional information from datasets. Therefore, the use of both the ranking and clustering methods could be a useful tool to be applied in biomonitoring studies of trace elements. - Highlights: • Surface and in-wax fractions showed different trace element

  2. Dalbergia sissoo Roxb. (English: Sissoo; Hindi: Shisham or Sisam ...

    Indian Academy of Sciences (India)

    Dalbergia sissoo Roxb. (English: Sissoo; Hindi: Shisham or Sisam) of Leguminosae is a tall deciduous tree with a light crown and compound leaves. Flowers are pale yellow in branched inflorescence. Fruit pods are borne on long stalks. The tree yields good quality timber and is often planted on roadsides and as shade ...

  3. Fulltext PDF

    Indian Academy of Sciences (India)

    IAS Admin

    LEAVED ALANGIUM) of Alangiaceae is a small deciduous tree, sometimes straggling and sometimes spinous. Leaves are alternate, variable, narrowly oblong or ovate-lanceolate. Flowers are in axillary fascicles. They are 1.5–2 cms long, white in color, attractive when in clusters and are sweet-scented. Fruits are ovoid or ...

  4. Chemical composition, rumen degradability, protein utilization and lactation response to selected tree leaves as substitute of cottonseed cake in the diet of dairy goats

    NARCIS (Netherlands)

    Khan, N.A.; Habib, G.; Ullah, G.

    2009-01-01

    The aim of this study was to investigate the potential of leaves from Grewia oppositifolia (G. oppositifolia) and Ziziphus mauritiana (Z. mauritiana) as a crude protein (CP) supplements to low quality diets of goats in Pakistan. Chemical composition and CP degradability of the tree leaves were

  5. Ecophysiological Remote Sensing of Leaf-Canopy Photosynthetic Characteristics in a Cool-Temperate Deciduous Forest in Japan

    Science.gov (United States)

    Noda, H. M.; Muraoka, H.

    2014-12-01

    Satellite remote sensing of structure and function of canopy is crucial to detect temporal and spatial distributions of forest ecosystems dynamics in changing environments. The spectral reflectance of the canopy is determined by optical properties (spectral reflectance and transmittance) of single leaves and their spatial arrangements in the canopy. The optical properties of leaves reflect their pigments contents and anatomical structures. Thus detailed information and understandings of the consequence between ecophysiological traits and optical properties from single leaf to canopy level are essential for remote sensing of canopy ecophysiology. To develop the ecophysiological remote sensing of forest canopy, we have been promoting multiple and cross-scale measurements in "Takayama site" belonging to AsiaFlux and JaLTER networks, located in a cool-temperate deciduous broadleaf forest on a mountainous landscape in Japan. In this forest, in situ measurement of canopy spectral reflectance has been conducted continuously by a spectroradiometer as part of the "Phenological Eyes Network (PEN)" since 2004. To analyze the canopy spectral reflectance from leaf ecophysiological viewpoints, leaf mass per area, nitrogen content, chlorophyll contents, photosynthetic capacities and the optical properties have been measured for dominant canopy tree species Quercus crispla and Betula ermanii throughout the seasons for multiple years.Photosynthetic capacity was largely correlated with chlorophyll contents throughout the growing season in both Q. crispla and B. ermanii. In these leaves, the reflectance at "red edge" (710 nm) changed by corresponding to the changes of chlorophyll contents throughout the seasons. Our canopy-level examination showed that vegetation indices obtained by red edge reflectance have linear relationship with leaf chlorophyll contents and photosynthetic capacity. Finally we apply this knowledge to the Rapid Eye satellite imagery around Takayama site to scale

  6. Rainfall interception of three trees in Oakland, California

    Science.gov (United States)

    Qingfu Xiao; E. Gregory McPherson

    2011-01-01

    A rainfall interception study was conducted in Oakland, California to determine the partitioning of rainfall and the chemical composition of precipitation, throughfall, and stemflow. Rainfall interception measurements were conducted on a gingko (Ginkgo biloba) (13.5 m tall deciduous tree), sweet gum (Liquidambar styraciflua) (8...

  7. Flowering Trees

    Indian Academy of Sciences (India)

    IAS Admin

    Flowering Trees. Ailanthus excelsa Roxb. (INDIAN TREE OF. HEAVEN) of Simaroubaceae is a lofty tree with large pinnately compound alternate leaves, which are ... inflorescences, unisexual and greenish-yellow. Fruits are winged, wings many-nerved. Wood is used in making match sticks. 1. Male flower; 2. Female flower.

  8. Effectivity of Betel Leaf (Piper betle L. Gel Extract in Shortening Bleeding Time After Deciduous Tooth Extraction

    Directory of Open Access Journals (Sweden)

    Regina Tedjasulaksana

    2017-01-01

    Full Text Available Background: As an Indonesian traditional medicine, betel leafis often used to stop nosebleed. Effective substances in betel leaves which serves to stop the bleeding is tannin. Objective: The aim of this study was to determine the effectiveness of the betel leaf ethanol extract gel shortened bleeding time after the revocation of deciduous teeth. Method: This research was conducted at the Department of Dental Nursing Clinic, Health Polytechnic Denpasar.This study is pure experimental research design with Completely Randomized Post Test Only Control Group Design. The total sample of 27 respondents were divided into a treatment group and two control groups. Anterior deciduous teeth on the physiological loose grade 3 or 4 is extracted, then the tooth socket is put pure gel for group 1 to group 2, epinephrine gel and gel ethanol extract of betel leaf for group 3. The bleeding time is calculated from the first moment the blood out until there is blood on filter paper that is placed on the tooth socket. Data were statistically analyzed with descriptive test and comparability test with One Way Anova. Result: The results showed bleeding time pure gel groups differ significantly with epinephrine group and the group of ethanol extract of betel leaf gel (p< 0.05. Bleeding time of epinephrine group did not differ significantly with betel leaf ethanol extract group (p>0.05. Conclusion: This means ethanol gel betel leaf extract can shorten bleeding after deciduous tooth extraction and it is suggested that the use of gel ethanol extract of betel leaves to cope with bleeding after tooth extraction.

  9. Estudo fenológico em três fases sucessionais de uma floresta estacional decidual no município de Santa Tereza, RS, Brasil Phenology study in three successional stages of a seasonal deciduous forest in Santa Tereza, RS, Brazil

    Directory of Open Access Journals (Sweden)

    Cáren Andreis

    2005-02-01

    Full Text Available O presente estudo foi realizado em 40 parcelas de área fixa pertencentes a três estágios sucessionais, denominados: Capoeirão, Floresta Secundária e Floresta Madura, em uma Floresta Estacional Decidual no município de Santa Tereza, RS. Foram realizadas observações fenológicas quinzenais em 53 espécies arbóreas, numa média de 8,4 indivíduos por espécie, durante o período de 16 de novembro de 2001 a 10 de novembro de 2002. As fenofases observadas foram floração, frutificação e mudança foliar. Os resultados indicaram que a atividade reprodutiva manteve uma porcentagem relativamente baixa nos três estágios sucessionais durante o período observado, com tendências em ser menor durante a estação de inverno. A quantidade total de folhas na árvore, não se distinguindo estágio sucessional, diminuiu de aproximadamente 85% no período de maior atividade vegetativa para até 35% no inverno, período de repouso, sendo a Floresta Madura a subsere, que manteve os maiores porcentuais de folhas durante o período estudado.The present study was accomplished in forty permanent plots belonging to three forest successional stages, denominated: Brush Forest, Secondary Forest and Mature Forest, in a seasonal deciduous forest in the municipal district of Santa Tereza, RS, Brazil. Phenologic observations were accomplished fortnightly for 53 arboreal species, in an average of 8,4 individuals per species, during the period of November 2001 to November 2002. The stages observed were flowering, fruiting and foliage change. The results indicate that the reproductive activity remained relatively low for three successional stages during the observed period, with a tendency to be even lower during winter. The total amount of leaves on the trees, regardless of the successional stage, decreased from approximately 85%, in the period of higher vegetative activity, to 35% in the winter, resting season. The Mature Forest maintained the largest percentage

  10. Celastraceae

    NARCIS (Netherlands)

    Stoffers, A.L.

    1984-01-01

    Trees or shrubs, sometimes climbing or twining. Leaves alternate or opposite, simple, deciduous or persistent. Stipules small and caducous or wanting. Inflorescence generally consisting of axillary cymes; pedicels commonly jointed. Flowers hermaphrodite or functionally unisexual, actinomorphous.

  11. 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.

  12. Ectopic decidual reaction mimicking inguinal lymphoma on ultrasound

    DEFF Research Database (Denmark)

    Lorentzen, C.; Prangsgaard, Tina; Lorentzen, Torben

    2014-01-01

    Ectopic decidual reaction has been described in various intraperitoneal locations. We present a case of unusual ectopic decidual reaction in the groin mimicking inguinal lymphoma on ultrasound in a pregnant woman. This case contributes evidence illustrating the variability of the clinical...... presentation of ectopic decidual reaction....

  13. Litter input controls on soil carbon in a temperate deciduous forest

    DEFF Research Database (Denmark)

    Bowden, Richard D.; Deem, Lauren; Plante, Alain F.

    2014-01-01

    Above- and belowground litter inputs in a temperate deciduous forest were altered for 20 yr to determine the importance of leaves and roots on soil C and soil organic matter (SOM) quantity and quality. Carbon and SOM quantity and quality were measured in the O horizon and mineral soil to 50 cm...... soil C, but decreases in litter inputs resulted in rapid soil C declines. Root litter may ultimately provide more stable sources of soil C. Management activities or environmental alterations that decrease litter inputs in mature forests can lower soil C content; however, increases in forest...

  14. Effect of Tree Leaves on Rumen Fermentation, Microbial Count and Blood Urea Nitrogen of West African Dwarf Goats

    Directory of Open Access Journals (Sweden)

    Adelusi, O. O.

    2016-12-01

    Full Text Available This experiment was carried out to assess the effect of Azadirachta indica, Newbouldia laevis and Spondias mombin leaves on rumen fermentation, microbial count and blood urea nitrogen (BUN of West African Dwarf (WAD goats. Sixteen WAD bucks (11.6 ? 0.9 kg in body weight were allocated to 4 treatments: 1 Control and 2 40 g/day of Azadirachta indica, 3 40 g/day of Newbouldia laevis and 4 40 g/day of Spondias mombin leaves arranged in a completely randomised design. The ground leaves were included in concentrate diets served on dry matter basis at 2% of body weight while Panicum maximum was fed ad libitum. The control diet had no tree leaves. Data were collected on chemical composition, rumen fermentation and microbial ecology, and BUN. Saponin was highest (P < 0.05 in S. mombin (8.14% while A. indica and N. laevis had 5.78% and 1.56%, respectively. Rumen ammonia nitrogen was least (P < 0.05 in goats fed A. indica (8.35 mg/dL while the highest (P < 0.05 total volatile fatty acid (TVFA was obtained from goats fed S. mombin with 125.51 mM. Goats fed N. laevis yielded the highest (P < 0.05 acetate with 70.65 mol/100 mol while propionate production was highest (P < 0.05 in the rumen of goats fed S. mombin (27.15 mol/100 mol. Viable bacteria count was lowest (P < 0.05 in rumen of goats fed A. indica (3.95?1012 cfu/ml while the least (P < 0.05 protozoa population was obtained from the rumen of bucks fed S. mombin (4.18?109 cfu/ml. All goats in the treatments containing tree leaves had higher (P < 0.05 and a rapid increase in BUN between 0 and 6 h post feeding when compared with the Control. It is concluded that feeding ground leaves of S. mombin to goats increases rumen total volatile fatty acid and propionate production and reduces the protozoa population.

  15. jfewr ©2016 - jfewr Publications

    African Journals Online (AJOL)

    J FOR WDLIFE & ENVIR

    Moringa oleifera), Pawpaw (Carica papaya), Coconut tree (Cocus nusifera) .... conserve water loss through transpiration. Neem is a deciduous plant which has to shed its leaves and fruits in order to get ready for another flowering and fruit.

  16. SEASONAL VARIATION IN LIGHT TRANSMISSION AND CANOPY GAPS OF DECIDUOUS ROADSIDE VEGETATION: ASSESSMENT WITHIN FOREST LANDSCAPE

    OpenAIRE

    Öztürk, Melih; Gökyer, Ercan

    2015-01-01

    Deciduous roadside vegetation exhibits seasonal patterns of foliage with varying colors and numbers. Hence the alternating percentage of the gaps within the roadside canopy allows changing percentages of light transmission throughout the year. The leafless roadside vegetation in winter is sequentially subject to budburst, flushing, and development stages until the summer, when the leaves are fully developed both in size and number. Then, defoliation follows senescence, and fading and fall sta...

  17. Feronia limonia (L.) Swingle (Elephant apple; Hindi-Kaithbelj is a ...

    Indian Academy of Sciences (India)

    Feronia limonia (L.) Swingle (Elephant apple; Hindi-Kaithbelj is a deciduous thorny tree with aromatic leaves and small white flowers. Fruits are large, globose ofthe size of tennis balls with a hard shell. The pulp of ripe fruit is sweet and edible. The gum exudate from the tree is used in dying and coloring. The wood is made ...

  18. Markedly Divergent Tree Assemblage Responses to Tropical Forest Loss and Fragmentation across a Strong Seasonality Gradient.

    Science.gov (United States)

    Orihuela, Rodrigo L L; Peres, Carlos A; Mendes, Gabriel; Jarenkow, João A; Tabarelli, Marcelo

    2015-01-01

    We examine the effects of forest fragmentation on the structure and composition of tree assemblages within three seasonal and aseasonal forest types of southern Brazil, including evergreen, Araucaria, and deciduous forests. We sampled three southernmost Atlantic Forest landscapes, including the largest continuous forest protected areas within each forest type. Tree assemblages in each forest type were sampled within 10 plots of 0.1 ha in both continuous forests and 10 adjacent forest fragments. All trees within each plot were assigned to trait categories describing their regeneration strategy, vertical stratification, seed-dispersal mode, seed size, and wood density. We detected differences among both forest types and landscape contexts in terms of overall tree species richness, and the density and species richness of different functional groups in terms of regeneration strategy, seed dispersal mode and woody density. Overall, evergreen forest fragments exhibited the largest deviations from continuous forest plots in assemblage structure. Evergreen, Araucaria and deciduous forests diverge in the functional composition of tree floras, particularly in relation to regeneration strategy and stress tolerance. By supporting a more diversified light-demanding and stress-tolerant flora with reduced richness and abundance of shade-tolerant, old-growth species, both deciduous and Araucaria forest tree assemblages are more intrinsically resilient to contemporary human-disturbances, including fragmentation-induced edge effects, in terms of species erosion and functional shifts. We suggest that these intrinsic differences in the direction and magnitude of responses to changes in landscape structure between forest types should guide a wide range of conservation strategies in restoring fragmented tropical forest landscapes worldwide.

  19. Markedly Divergent Tree Assemblage Responses to Tropical Forest Loss and Fragmentation across a Strong Seasonality Gradient.

    Directory of Open Access Journals (Sweden)

    Rodrigo L L Orihuela

    Full Text Available We examine the effects of forest fragmentation on the structure and composition of tree assemblages within three seasonal and aseasonal forest types of southern Brazil, including evergreen, Araucaria, and deciduous forests. We sampled three southernmost Atlantic Forest landscapes, including the largest continuous forest protected areas within each forest type. Tree assemblages in each forest type were sampled within 10 plots of 0.1 ha in both continuous forests and 10 adjacent forest fragments. All trees within each plot were assigned to trait categories describing their regeneration strategy, vertical stratification, seed-dispersal mode, seed size, and wood density. We detected differences among both forest types and landscape contexts in terms of overall tree species richness, and the density and species richness of different functional groups in terms of regeneration strategy, seed dispersal mode and woody density. Overall, evergreen forest fragments exhibited the largest deviations from continuous forest plots in assemblage structure. Evergreen, Araucaria and deciduous forests diverge in the functional composition of tree floras, particularly in relation to regeneration strategy and stress tolerance. By supporting a more diversified light-demanding and stress-tolerant flora with reduced richness and abundance of shade-tolerant, old-growth species, both deciduous and Araucaria forest tree assemblages are more intrinsically resilient to contemporary human-disturbances, including fragmentation-induced edge effects, in terms of species erosion and functional shifts. We suggest that these intrinsic differences in the direction and magnitude of responses to changes in landscape structure between forest types should guide a wide range of conservation strategies in restoring fragmented tropical forest landscapes worldwide.

  20. Long-term effects of climate change on carbon storage and tree species composition in a dry deciduous forest.

    Science.gov (United States)

    Fekete, István; Lajtha, Kate; Kotroczó, Zsolt; Várbíró, Gábor; Varga, Csaba; Tóth, János Attila; Demeter, Ibolya; Veperdi, Gábor; Berki, Imre

    2017-08-01

    Forest vegetation and soils have been suggested as potentially important sinks for carbon (C) with appropriate management and thus are implicated as effective tools in stabilizing climate even with increasing anthropogenic release of CO 2 . Drought, however, which is often predicted to increase in models of future climate change, may limit net primary productio (NPP) of dry forest types, with unknown effects on soil C storage. We studied C dynamics of a deciduous temperate forest of Hungary that has been subject to significant decreases in precipitation and increases in temperature in recent decades. We resampled plots that were established in 1972 and repeated the full C inventory by analyzing more than 4 decades of data on the number of living trees, biomass of trees and shrubs, and soil C content. Our analyses show that the decline in number and biomass of oaks started around the end of the 1970s with a 71% reduction in the number of sessile oak stems by 2014. Projected growth in this forest, based on the yield table's data for Hungary, was 4.6 kg C/m 2 . Although new species emerged, this new growth and small increases in oak biomass resulted in only 1.9 kg C/m 2 increase over 41 years. The death of oaks increased inputs of coarse woody debris to the surface of the soil, much of which is still identifiable, and caused an increase of 15.5%, or 2.6 kg C/m 2 , in the top 1 m of soil. Stability of this fresh organic matter input to surface soil is unknown, but is likely to be low based on the results of a colocated woody litter decomposition study. The effects of a warmer and drier climate on the C balance of forests in this region will be felt for decades to come as woody litter inputs decay, and forest growth remains impeded. © 2017 John Wiley & Sons Ltd.

  1. Comparative expression profiling of Nicotiana benthamiana leaves systemically infected with three fruit tree viruses.

    Science.gov (United States)

    Dardick, Christopher

    2007-08-01

    Plant viruses cause a wide array of disease symptoms and cytopathic effects. Although some of these changes are virus specific, many appear to be common even among diverse viruses. Currently, little is known about the underlying molecular determinants. To identify gene expression changes that are concomitant with virus symptoms, we performed comparative expression profiling experiments on Nicotiana benthamiana leaves infected with one of three different fruit tree viruses that produce distinct symptoms: Plum pox potyvirus (PPV; leaf distortion and mosaic), Tomato ringspot nepovirus (ToRSV; tissue necrosis and general chlorosis), and Prunus necrotic ringspot ilarvirus (PNRSV; subtle chlorotic mottling). The numbers of statistically significant genes identified were consistent with the severity of the observed symptoms: 1,082 (ToRSV), 744 (PPV), and 89 (PNRSV). In all, 56% of the gene expression changes found in PPV-infected leaves also were altered by ToRSV, 87% of which changed in the same direction. Both PPV- and ToRSV-infected leaves showed widespread repression of genes associated with plastid functions. PPV uniquely induced the expression of large numbers of cytosolic ribosomal genes whereas ToRSV repressed the expression of plastidic ribosomal genes. How these and other observed expression changes might be associated with symptom development are discussed.

  2. Oleaceae

    NARCIS (Netherlands)

    Stoffers, A.L.

    1982-01-01

    Evergreen or deciduous trees or shrubs or sometimes woody vines. Leaves opposite, verticillate or very rarely alternate, simple or pinnately compound. Stipules wanting. Inflorescence consisting of mostly terminal dichasial panicles or cymes. Bracts and braoteoles present. Flowers hermaphrodite or

  3. Explaining the dependence of climatic response of tree radial growth on permafrost

    Science.gov (United States)

    Bryukhanova, Marina; Benkova, Anna; von Arx, Georg; Fonti, Patrick; Simanko, Valentina; Kirdyanov, Alexander; Shashkin, Alexander

    2015-04-01

    In northern regions of Siberia it is infrequent to have long-term observations of the variability of soil features, phenological data, duration of the growing season, which can be used to infer the influence of the environment on tree growth and productivity. The best way to understand tree-growth and tree responses to environmental changes is to make use of mechanistic models, allowing to combine already available experiment/field data with other parameters based on biological principles of tree growth. The goal of our study is to estimate which tree species (deciduous, conifer deciduous or conifer evergreen) is more plastic under possible climate changes in permafrost zone. The studied object is located in the northern part of central Siberia, Russia (64°N, 100°E). The study plot was selected within a post-fire succession and representatives for 100 years old even aged mixed forest of Larix gmelinii (Rupr.) Rupr. and Betula pubescens Ehrh. with few exemplars of Spruce (Picea obovata Ledeb.). To understand physiological response of larch, birch and spruce trees to climatic changes the ecological-physiological process-based model of tree photosynthesis (Benkova and Shashkin 2003) was applied. Multiparametric tree-ring chronologies were analyzed and correlated with climatic parameters over the last 77 years. This work is supported by the Ministry of Education and Science of the Russian Federation (Grant from the President of RF for Young Scientists MK-1589.2014.4).

  4. Using niche-based modelling to assess the impact of climate change on tree functional diversity in Europe

    DEFF Research Database (Denmark)

    Thuiller, Wilfried; Lavorel, Sandra; Sykes, Martin T.

    2006-01-01

    Rapid anthropogenic climate change is already affecting species distributions and ecosystem functioning worldwide. We applied niche-based models to analyse the impact of climate change on tree species and functional diversity in Europe. Present-day climate was used to predict the distributions...... of 122 tree species from different functional types (FT). We then explored projections of future distributions under one climate scenario for 2080, considering two alternative dispersal assumptions: no dispersal and unlimited dispersal. The species-rich broadleaved deciduous group appeared to play a key...... role in the future of different European regions. Temperate areas were projected to lose both species richness and functional diversity due to the loss of broadleaved deciduous trees. These were projected to migrate to boreal forests, thereby increasing their species richness and functional diversity...

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

    International Nuclear Information System (INIS)

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

    2014-01-01

    Canopy-level stomatal conductance over a warm-temperate mixed deciduous and evergreen broadleaf forest in Japan was estimated by the Penman–Monteith approach, as compensated by a semi-empirical photosynthesis-dependent stomatal model, where photosynthesis, relative humidity, and CO 2 concentration were assumed to regulate stomatal conductance. This approach, using eddy covariance data and routine meteorological observations at a flux tower site, permits the continuous estimation of canopy-level O 3 uptake, even when the Penman–Monteith approach is unavailable (i.e. in case of direct evaporation from soil or wet leaves). Distortion was observed between the AOT40 exposure index and O 3 uptake through stomata, as AOT40 peaked in April, but with O 3 uptake occurring in July. Thus, leaf pre-maturation in the predominant deciduous broadleaf tree species (Quercus serrata) might suppress O 3 uptake in springtime, even when the highest O 3 concentrations were observed. -- Highlights: • We estimate canopy-level O 3 uptake in a warm-temperate mixed forest in Japan. • The Penman–Monteith approach is compensated by a photosynthesis-dependent model. • Stomatal conductance can be estimated, even in a partly-opened or wet canopy. • The estimated O 3 dose peaks in summer though O 3 exposure peaks in spring. -- Estimation of seasonal O 3 uptake over a mixed-temperate forest compensated by a photosynthesis-dependent stomatal model

  6. Bombacaceae

    NARCIS (Netherlands)

    Stoffers, A.L.

    1984-01-01

    Trees, often with very thick trunks, all parts covered by stellate hairs or squamae. Leaves alternate, simple, or digitately compound. Stipules deciduous. Flowers mostly solitary, often very large. Flowers hermaphrodite, 5-merous. Calyx valvate. Epicalyx present or wanting. Petals contorted. Stamens

  7. Investigating the role of evergreen and deciduous forests in the increasing trend in atmospheric CO2 seasonal amplitude

    Science.gov (United States)

    Welp, L.; Calle, L.; Graven, H. D.; Poulter, B.

    2017-12-01

    The seasonal amplitude of Northern Hemisphere atmospheric CO2 concentrations has systematically increased over the last several decades, indicating that the timing and amplitude of net CO2 uptake and release by northern terrestrial ecosystems has changed substantially. Remote sensing, dynamic vegetation modeling, and in-situ studies have explored how changes in phenology, expansion of woody vegetation, and changes in species composition and disturbance regimes, among others, are driven by changes in climate and CO2. Despite these efforts, ecosystem models have not been able to reproduce observed atmospheric CO2 changes. Furthermore, the implications for the source/sink balance of northern ecosystems remains unclear. Changing proportions of evergreen and deciduous tree cover in response to climate change could be one of the key mechanisms that have given rise to amplified atmospheric CO2 seasonality. These two different plant functional types (PFTs) have different carbon uptake seasonal patterns and also different sensitivities to climate change, but are often lumped together as one forest type in global ecosystem models. We will demonstrate the potential that shifting distributions of evergreen and deciduous forests can have on the amplitude of atmospheric CO2. We will show phase differences in the net CO2 seasonal uptake using CO2 flux data from paired evergreen/deciduous eddy covariance towers. We will use simulations of evergreen and deciduous PFTs from the LPJ dynamic vegetation model to explore how climate change may influence the abundance and CO2 fluxes of each. Model results show that the area of deciduous forests is predicted to have increased, and the seasonal amplitude of CO2 fluxes has increased as well. The impact of surface flux seasonal variability on atmospheric CO2 amplitude is examined by transporting fluxes from each forest PFT through the TM3 transport model. The timing of the most intense CO2 uptake leads to an enhanced effect of deciduous

  8. Nutrient retranslocation in forest species in the Brazilian Amazon

    Directory of Open Access Journals (Sweden)

    Murilo Rezende Machado

    2016-01-01

    Full Text Available Internal retranslocation is an important mechanism for nutrient conservation in plants, which depends on different factors. However, there are little data about this subject, especially on tropical forest species. This study aimed to evaluate the macronutrient retranslocation dynamic and the influence of ecological (P: pioneer x NP: non-pioneer and phenological (ND: non-deciduous x D: semideciduous / deciduous characteristics on the macronutrient content of leaves of five tree species on monospecific plantations in the Brazilian Amazon: Acacia mangium Willd., Parkia decussata Ducke, Dipteryx odorata (Aublet Willd., Jacaranda copaia (Aubl. D. Don and Swietenia macrophylla King. Photosynthetically active green leaves and senescent leaves (leaf litter were collected. Retranslocation was estimated through an equation proposed by Attiwill, Guthrie and Leuning (1978. The pioneer species presented higher foliar contents of N; the non-pioneer species presented higher contents of K, Ca and S; and the results were inconclusive for P and Mg. The deciduous species presented higher foliar contents of K and of P, whereas the foliar contents of N, Ca, Mg and S were virtually identical between the phenological groups. The internal retranslocation of foliar nutrients in pioneer and non-deciduous species was higher than that of non-pioneer and deciduous species.

  9. Remediation Potential of Forest Forming Tree Species Within Northern Steppe Reclamation Stands

    Directory of Open Access Journals (Sweden)

    Zverkovskyy Vasiliy M.

    2018-03-01

    Full Text Available The aim of the research was to study the features of accumulation of heavy metals by assimilation apparatus of coniferous and deciduous arboreous plants. The research identified excess of factual concentrations for Arsenic in mining rock in relation to values stated in IPC (indicative permissible concentrations. It is stated that the metals can be divided into three groups according to their absolute content in unit of foliage biomass. The element of excessive concentration is Mn, medium concentration is characteristic for Pb and Zn and low concentration is observed for Sb, Cr, As, Cu, Ni and Sn. Calculation of coefficient of biological accumulation of the metals under research has shown its high values for Crimean pine. The data presented for Black locust indicate low values of coefficient of biological accumulation, which is best noticeable for Chromium, Antimony and Tin. It is determined that a small amount of Sb and Sn are a subject to uptake by Black locust leaves, whilst for Crimean pine needles, Sb and As are characterised by the lowest inflow. The average content of lead is 209.11 kg·ha−1 for Crimean pine in all age groups of trees, whilst for Black locust, this index is only 15.52 kg·ha−1, which is 13.5 times less. Zinc accumulation is better performed by Black locust leaves, and it gradually decreases with increasing age. No definite trend of redistribution and subsequent accumulation of copper depending on tree species and age was found.

  10. Dominance of legume trees alters nutrient relations in mixed species forest restoration plantings within seven years

    Science.gov (United States)

    Ilyas Siddique; Vera Lex Engel; David Lamb; Gabriela B. Nardoto; Jean P.H.B. Ometto; Luiz A. Martinelli; Susanne. Schmidt

    2008-01-01

    Failures in reforestation are often attributed to nutrient limitation for tree growth. We compared tree performance and nitrogen and phosphorus relations in adjacent mixed-species plantings of contrasting composition, established for forest restoration on Ultisol soil, originally covered by tropical semi-deciduous Atlantic Forest in Southeast Brazil. Nutrient relations...

  11. Understory Structure and Vascular Plant Diversity in Naturally Regenerated Deciduous Forests and Spruce Plantations on Similar Clear-Cuts: Implications for Forest Regeneration Strategy Selection

    Directory of Open Access Journals (Sweden)

    ZhiQiang Fang

    2014-04-01

    Full Text Available The active effect of natural regeneration on understory vegetation and diversity on clear-cut forestlands, in contrast to conifer reforestation, is still controversial. Here we investigated differences in understory vegetation by comparing naturally regenerated deciduous forests (NR and reforested spruce plantations (SP aged 20–40 years on 12 similar clear-cuts of subalpine old-growth spruce-fir forests from the eastern Tibetan Plateau. We found that 283 of the 334 vascular plant species recorded were present in NR plots, while only 264 species occurred in SP plots. This was consistent with richer species, higher cover, and stem (or shoot density of tree seedlings, shrubs, and ferns in the NR plots than in the SP plots. Moreover, understory plant diversity was limited under dense canopy cover, which occurred more frequently in the SP plots. Our findings implied that natural deciduous tree regeneration could better preserve understory vegetation and biodiversity than spruce reforestation after clear-cutting. This result further informed practices to reduce tree canopy cover for spruce plantations or to integrate natural regeneration and reforestation for clear-cuts in order to promote understory vegetation and species diversity conservation.

  12. Effect of the air pollution by heavy metals in the tree leaves in the metropolitan area of Toluca Valley

    International Nuclear Information System (INIS)

    Ledesma O, C. I.

    2014-01-01

    Leaves of two tree species: Juniperus sp and Ligustrum sp were studied as indicators of pollution heavy metals (Mn, Fe, Cu, Zn and Pb) in the atmosphere of the Metropolitan Area of the Toluca Valley. Bio markers of catalase, superoxide dismutase, ascorbate peroxidase, guaiacol, proteins and pigments were measured in order to determine the effects to atmospheric stress caused by heave metals during two periods in the year (December 2012 and May 2013). Metals were quantified in dry deposit and tissue on trees tissue leaves using the technique of Energy Dispersive X-ray Fluorescence Spectroscopy and Total Reflection X-ray Fluorescence Spectroscopy respectively. The results show greater response of enzyme inhibition in Juniperus sp. species, with decreased protein content and increased lipid peroxidation at sites with higher content of metals in tissue belonging to urban areas with increased industrial activity and traffic flow. In dry deposit bioavailability factor of metals was Fe>Mn> Zn> Cu>Pb for the first time of sampling and Fe>Mn> Cu> Zn>Pb for the second sampling period. (Author)

  13. Community patterns of tropical tree phenology derived from Unmanned Aerial Vehicle images: intra- and interspecific variation, association with species plant traits, and response to interannual climate variation

    Science.gov (United States)

    Bohlman, Stephanie; Rifai, Sami; Park, John; Dandois, Jonathan; Muller-Landau, Helene

    2017-04-01

    Phenology is a key life history trait of plant species and critical driver of ecosystem processes. There is strong evidence that phenology is shifting in temperate ecosystems in response to climate change, but tropical forest phenology remains poorly quantified and understood. A key challenge is that tropical forests contain hundreds of plant species with a wide variety of phenological patterns, which makes it difficult to collect sufficient ground-based field data to characterize individual tropical tree species phenologies. Satellite-based observations, an important source of phenology data in northern latitudes, are hindered by frequent cloud cover in the tropics. To quantify phenology over a large number of individuals and species, we collected bi-weekly images from unmanned aerial vehicles (UAVs) in the well-studied 50-ha forest inventory plot on Barro Colorado Island, Panama. The objective of this study is to quantify inter- and intra-specific responses of tropical tree leaf phenology to environmental variation over large spatial scales and identify key environmental variables and physiological mechanisms underpinning phenological variation. Between October 2014 and December 2015 and again in May 2015, we collected a total of 35 sets of UAV images, each with continuous coverage of the 50-ha plot, where every tree ≥ 1 cm DBH is mapped. UAV imagery was corrected for exposure, orthorectified, and then processed to extract spectral, texture, and image information for individual tree crowns, which was then used as inputs for a machine learning algorithm that successfully predicted the percentages of leaf, branch, and flower cover for each tree crown (r2=0.76 between observed and predicted percent branch cover for individual tree crowns). We then quantified cumulative annual deciduousness for each crown by fitting a non-parametric curve of flexible shape to its predicted percent branch time series and calculated the area under the curve. We obtained the species

  14. Fruit production in three masting tree species does not rely on stored carbon reserves.

    Science.gov (United States)

    Hoch, Günter; Siegwolf, Rolf T W; Keel, Sonja G; Körner, Christian; Han, Qingmin

    2013-03-01

    Fruiting is typically considered to massively burden the seasonal carbon budget of trees. The cost of reproduction has therefore been suggested as a proximate factor explaining observed mast-fruiting patterns. Here, we used a large-scale, continuous (13)C labeling of mature, deciduous trees in a temperate Swiss forest to investigate to what extent fruit formation in three species with masting reproduction behavior (Carpinus betulus, Fagus sylvatica, Quercus petraea) relies on the import of stored carbon reserves. Using a free-air CO2 enrichment system, we exposed trees to (13)C-depleted CO2 during 8 consecutive years. By the end of this experiment, carbon reserve pools had significantly lower δ(13)C values compared to control trees. δ(13)C analysis of new biomass during the first season after termination of the CO2 enrichment allowed us to distinguish the sources of built-in carbon (old carbon reserves vs. current assimilates). Flowers and expanding leaves carried a significant (13)C label from old carbon stores. In contrast, fruits and vegetative infructescence tissues were exclusively produced from current, unlabeled photoassimilates in all three species, including F. sylvatica, which had a strong masting season. Analyses of δ(13)C in purified starch from xylem of fruit-bearing shoots revealed a complete turn-over of starch during the season, likely due to its usage for bud break. This study is the first to directly demonstrate that fruiting is independent from old carbon reserves in masting trees, with significant implications for mechanistic models that explain mast seeding.

  15. Moringaceae

    NARCIS (Netherlands)

    Steenis, van C.G.G.J.

    1948-01-01

    Small trees, mostly deciduous, bark gummy, wood soft, roots thickened, pungent; trunk often inflated. Leaves spread, imperfectly 2—4-imparipinnate; tissue with myrosin cells; pinnae opposite, provided with stipitate glands at the base of the petiolules and pinnae. Leaflets small, opposite, entire,

  16. Synthesis of silver nano-materials from Grevillea robusta A Cunn (Silver-oak tree) leaves extract and shape directing role of cetyltrimethylammonium bromide

    International Nuclear Information System (INIS)

    Ahmad, Rabia; Faisal, Qamer; Hussain, Sajjad

    2016-01-01

    Grevillea robusta (Silver-oak tree) tree is a medicinal tree. Conventional UV-visible spectrophotometric and transmission electron microscopic technique were used to determine the morphology of silver nanoplates (AgNP) using Grevillea robusta (Silver-oak tree) aqueous leaves extract for the first time. The visible spectra showed the presence of three well defined surface plasmon absorption (SPR) bands at 500, 550 and 675 nm which was attributed to the anisotropic growth of Ag-nanoplates. Transmission electron microscopic (TEM) analysis of AgNP showed formation of truncated triangular, polyhedral with some irregular shapes nanoplates in the size range 8-20 nm. Cetyltrimethylammonium bromide (CTAB) has no significant effect on the shape of the spectra, position of SPR bands, size and size distribution of AgNP.

  17. Synthesis of silver nano-materials from Grevillea robusta A Cunn (Silver-oak tree) leaves extract and shape directing role of cetyltrimethylammonium bromide

    Energy Technology Data Exchange (ETDEWEB)

    Ahmad, Rabia; Faisal, Qamer; Hussain, Sajjad [Department of Chemistry, Jamia Millia Islamia (Central University), New Delhi-110025 (India)

    2016-05-23

    Grevillea robusta (Silver-oak tree) tree is a medicinal tree. Conventional UV-visible spectrophotometric and transmission electron microscopic technique were used to determine the morphology of silver nanoplates (AgNP) using Grevillea robusta (Silver-oak tree) aqueous leaves extract for the first time. The visible spectra showed the presence of three well defined surface plasmon absorption (SPR) bands at 500, 550 and 675 nm which was attributed to the anisotropic growth of Ag-nanoplates. Transmission electron microscopic (TEM) analysis of AgNP showed formation of truncated triangular, polyhedral with some irregular shapes nanoplates in the size range 8-20 nm. Cetyltrimethylammonium bromide (CTAB) has no significant effect on the shape of the spectra, position of SPR bands, size and size distribution of AgNP.

  18. A novel approach for individual tree crown delineation using lidar data

    Science.gov (United States)

    Liu, Tao

    Individual tree crown delineation (ITCD) is an important technique to support precision forestry. ITCD is particularly difficult for deciduous forests where the existence of multiple branches can lead to false tree top detection. This thesis focused on developing a new ITCD model, which consists of two components: (1) boundary refinement using a novel algorithm called Fishing Net Dragging (FiND), and (2) segment merging using boundary classification. The proposed ITCD model was tested in both deciduous and mixed forests, attaining an overall accuracy of 74% and 78%, respectively. This compared favorably to an ITCD method commonly cited in the literature, which attained 41% and 51% on the same plots. To facilitate comparison of research in the ITCD community, this thesis also developed a new accuracy assessment scheme for ITCD. This new accuracy assessment is easy to interpret and convenient to implement while comprehensively evaluating ITCD accuracy.

  19. Comprehensive national database of tree effects on air quality and human health in the United States

    Science.gov (United States)

    Satoshi Hirabayashi; David J. Nowak

    2016-01-01

    Trees remove air pollutants through dry deposition processes depending upon forest structure, meteorology, and air quality that vary across space and time. Employing nationally available forest, weather, air pollution and human population data for 2010, computer simulations were performed for deciduous and evergreen trees with varying leaf area index for rural and...

  20. Expansion of deciduous tall shrubs but not evergreen dwarf shrubs inhibited by reindeer in Scandes mountain range.

    Science.gov (United States)

    Vowles, Tage; Gunnarsson, Bengt; Molau, Ulf; Hickler, Thomas; Klemedtsson, Leif; Björk, Robert G

    2017-11-01

    One of the most palpable effects of warming in Arctic ecosystems is shrub expansion above the tree line. However, previous studies have found that reindeer can influence plant community responses to warming and inhibit shrubification of the tundra.We revisited grazed (ambient) and ungrazed study plots (exclosures), at the southern as well as the northern limits of the Swedish alpine region, to study long-term grazing effects and vegetation changes in response to increasing temperatures between 1995 and 2011, in two vegetation types (shrub heath and mountain birch forest).In the field layer at the shrub heath sites, evergreen dwarf shrubs had increased in cover from 26% to 49% but were unaffected by grazing. Deciduous dwarf and tall shrubs also showed significant, though smaller, increases over time. At the birch forest sites, the increase was similar for evergreen dwarf shrubs (20-48%) but deciduous tall shrubs did not show the same consistent increase over time as in the shrub heath.The cover and height of the shrub layer were significantly greater in exclosures at the shrub heath sites, but no significant treatment effects were found on species richness or diversity.July soil temperatures and growing season thawing degree days (TDD) were higher in exclosures at all but one site, and there was a significant negative correlation between mean shrub layer height and soil TDD at the shrub heath sites. Synthesis . This study shows that shrub expansion is occurring rapidly in the Scandes mountain range, both above and below the tree line. Tall, deciduous shrubs had benefitted significantly from grazing exclosure, both in terms of cover and height, which in turn lowered summer soil temperatures. However, the overriding vegetation shift across our sites was the striking increase in evergreen dwarf shrubs, which were not influenced by grazing. As the effects of an increase in evergreen dwarf shrubs and more recalcitrant plant litter may to some degree counteract some of

  1. Capturing characteristics of beryllium-7 in selected tree species

    International Nuclear Information System (INIS)

    Narazaki, Yukinori; Karube, Yoshiharu.

    1997-01-01

    With regard to 7 Be, a natural radioactive nuclide, the botanical capturing characteristics were compared between eight species of those trees which grow in a local district. The mechanism of such botanical capture by their leaves was discussed. The amounts of captured 7 Be were different by tree species. Higher radioactivities were found in the coniferous trees than in the broadleaf trees. The seasonal change of 7 Be radioactivity in leaves was significantly higher in winter and spring and lower in summer. Since airborne or fallout 7 Be particles stay on the upper face of leaves, the deposited amount depended on the surface area per weight of leaves particularly for evergreen trees. Because the 7 Be amount in leaves depended on the fallout capturing ability of leafs superficial skin as well as the cleaning effect of rain and the like, the radioactivity on the surface can change depending on the surface condition of leaves even in the case the levels of 7 Be fallout stayed the same. (author)

  2. Phenology of two Ficus species in seasonal semi-deciduous forest in Southern Brazil

    Directory of Open Access Journals (Sweden)

    E. Bianchini

    Full Text Available Abstract We analyzed the phenology of Ficus adhatodifolia Schott ex Spreng. (23 fig tree and F. eximia Schott (12 fig tree for 74 months in a remnant of seasonal semi-deciduous forest (23°27’S and 51°15’W, Southern Brazil and discussed their importance to frugivorous. Leaf drop, leaf flush, syconia production and dispersal were recorded. These phenophases occurred year-round, but seasonal peaks were recorded in both leaf phenophases for F. eximia and leaf flushing for F. adhatodifolia. Climatic variables analyzed were positively correlated with reproductive phenophases of F. adhatodifolia and negatively correlated with the vegetative phenophases of F. eximia. In despite of environmental seasonality, little seasonality in the phenology of two species was observed, especially in the reproductive phenology. Both species were important to frugivorous, but F. adhatodifolia can play a relevant role in the remnant.

  3. Patterns of diversity and regeneration in unmanaged moist deciduous forests in response to disturbance in Shiwalik Himalayas, India

    Directory of Open Access Journals (Sweden)

    Mukesh Kumar Gautam

    2016-06-01

    Full Text Available We studied vegetation attributes in Indian tropical moist deciduous unmanaged forests to determine the influence of forest disturbances on them. We enumerated 89 species: 72 under moderate disturbance and 54 under least disturbance. The data from 3399 stems [>5 cm diameter at breast height (dbh] decreased linearly along the disturbance gradient. The basal area was largest in least disturbed forests (61 m2/ha and smallest in intensely disturbed forest (41 m2/ha. Under least and moderate disturbance, tree density-diameter distribution had negative exponential curves, whereas highly disturbed forests had unimodal-shaped curves where a few trees 5–10 cm and >50 cm in diameter were recorded. Most tree and shrub layer species under heavy and intense disturbance had impaired regeneration. Moderate disturbance intensity thus apparently benefits species diversity, stand density, and regeneration. Decline in seedlings and saplings, especially tree species, threaten forest regeneration and the maintenance of species diversity of unmanaged tropical forests.

  4. Floristic-functional variation of tree component along an altitudinal gradient in araucaria forest areas, in Southern Brazil.

    Science.gov (United States)

    Soboleski, Vanessa F; Higuchi, Pedro; Silva, Ana Carolina DA; Silva, Mariele A F DA; Nunes, Amanda S; Loebens, Rodineli; Souza, Karine DE; Ferrari, Jheniffer; Lima, Carla L; Kilca, Ricardo V

    2017-01-01

    We aimed to investigate the taxonomic and functional variations of tree component of Araucaria Forest (AF) areas located along an altitudinal gradient (700, 900 and 1,600 m asl), in the southern region of Brazil. The functional traits determined were leaf area, specific leaf area, wood density, maximum potential height and dispersal syndromes and deciduousness. The data were analyzed through a functional and taxonomic dissimilarity dendrograms, community-weighted mean trait values, parametric and nonparametric tests, and Principal Component Analysis. The largest floristic-structural similarity was observed between the lower altitude areas (700 and 900 m asl), whose Bray-Curtis distance was 0.63. The area at 700 m asl was characterized by a predominance of deciduous and semi-deciduous species, with a high number of self- and wind-dispersed species, whereas the area at 1,600 m asl exhibited a predominance of animal-dispersed and evergreen species. It was also observed that there were significant variations for leaf traits, basic wood density and maximum potential height. Over all altitudinal gradient, the ordinations indicated that there was no evidence of functional differentiation among dispersal and deciduousness groups. In conclusion, the evaluated Araucaria Forest areas presented high floristic-functional variation of the tree component along the altitudinal gradient.

  5. Frost hardening and dehardening potential in temperate trees from winter to budburst.

    Science.gov (United States)

    Vitra, Amarante; Lenz, Armando; Vitasse, Yann

    2017-10-01

    We investigated how deciduous trees can adjust their freezing resistance in response to temperature during the progress of the ecodormancy phase, from midwinter to budburst. We regularly sampled twigs of four different temperate deciduous tree species from January to the leaf-out date. Using computer-controlled freezers and climate chambers, the freezing resistance of buds was measured directly after sampling and also after the application of artificial hardening and dehardening treatments, simulating cold and warm spells. The thermal time to budburst in forcing conditions (c. 20°C) was also quantified at each sampling as a proxy for dormancy depth. Earlier flushing species showed higher freezing resistance than late flushing species at either similar bud development stage or similar dormancy depth. Overall, freezing resistance and its hardening and dehardening potential dramatically decreased during the progress of ecodormancy and became almost nil during budburst. Our results suggest that extreme cold events in winter are not critical for trees, as freezing resistance can be largely enhanced during this period. By contrast, the timing of budburst is a critical component of tree fitness. Our results provide quantitative values of the freezing resistance dynamics during ecodormancy, particularly valuable in process-based species distribution models. © 2017 The Authors. New Phytologist © 2017 New Phytologist Trust.

  6. Towards the harmonization between National Forest Inventory and Forest Condition Monitoring. Consistency of plot allocation and effect of tree selection methods on sample statistics in Italy.

    Science.gov (United States)

    Gasparini, Patrizia; Di Cosmo, Lucio; Cenni, Enrico; Pompei, Enrico; Ferretti, Marco

    2013-07-01

    In the frame of a process aiming at harmonizing National Forest Inventory (NFI) and ICP Forests Level I Forest Condition Monitoring (FCM) in Italy, we investigated (a) the long-term consistency between FCM sample points (a subsample of the first NFI, 1985, NFI_1) and recent forest area estimates (after the second NFI, 2005, NFI_2) and (b) the effect of tree selection method (tree-based or plot-based) on sample composition and defoliation statistics. The two investigations were carried out on 261 and 252 FCM sites, respectively. Results show that some individual forest categories (larch and stone pine, Norway spruce, other coniferous, beech, temperate oaks and cork oak forests) are over-represented and others (hornbeam and hophornbeam, other deciduous broadleaved and holm oak forests) are under-represented in the FCM sample. This is probably due to a change in forest cover, which has increased by 1,559,200 ha from 1985 to 2005. In case of shift from a tree-based to a plot-based selection method, 3,130 (46.7%) of the original 6,703 sample trees will be abandoned, and 1,473 new trees will be selected. The balance between exclusion of former sample trees and inclusion of new ones will be particularly unfavourable for conifers (with only 16.4% of excluded trees replaced by new ones) and less for deciduous broadleaves (with 63.5% of excluded trees replaced). The total number of tree species surveyed will not be impacted, while the number of trees per species will, and the resulting (plot-based) sample composition will have a much larger frequency of deciduous broadleaved trees. The newly selected trees have-in general-smaller diameter at breast height (DBH) and defoliation scores. Given the larger rate of turnover, the deciduous broadleaved part of the sample will be more impacted. Our results suggest that both a revision of FCM network to account for forest area change and a plot-based approach to permit statistical inference and avoid bias in the tree sample

  7. Changes in sapwood permeability and anatomy with tree age and height in the broad-leaved evergreen species Eucalyptus regnans.

    Science.gov (United States)

    England, Jacqueline R; Attiwill, Peter M

    2007-08-01

    Increases in plant size and structural complexity with increasing age have important implications for water flow through trees. Water supply to the crown is influenced by both the cross-sectional area and the permeability of sapwood. It has been hypothesized that hydraulic conductivity within sapwood increases with age. We investigated changes in sapwood permeability (k) and anatomy with tree age and height in the broad-leaved evergreen species Eucalyptus regnans F. Muell. Sapwood was sampled at breast height from trees ranging from 8 to 240 years old, and at three height positions on the main stem of 8-year-old trees. Variation in k was not significant among sampling height positions in young trees. However, k at breast height increased with tree age. This was related to increases in both vessel frequency and vessel diameter, resulting in a greater proportion of sapwood being occupied by vessel lumina. Sapwood hydraulic conductivity (the product of k and sapwood area) also increased with increasing tree age. However, at the stand level, there was a decrease in forest sapwood hydraulic conductivity with increasing stand age, because of a decrease in the number of trees per hectare. Across all ages, there were significant relationships between k and anatomy, with individual anatomical characteristics explaining 33-62% of the variation in k. There was also strong agreement between measured k and permeability predicted by the Hagen-Poiseuille equation. The results support the hypothesis of an increase in sapwood permeability at breast height with age. Further measurements are required to confirm this result at other height positions in older trees. The significance of tree-level changes in sapwood permeability for stand-level water relations is discussed.

  8. Cesium accumulation in native trees from the Brazilian Cerrado

    International Nuclear Information System (INIS)

    Franca, E.J.D.; Miranda, M.V.F.E.S.; Santos, T.O.; Cantinha, R.S.; Fernandes, E.A.D.N.

    2016-01-01

    Even considered not essential for plants, cesium may cycle within forest ecosystems. Taking into account the lack of knowledge on the distribution of this chemical element in Brazilian ecosystems, this work encompasses the unexpected cesium accumulation in native plant leaves from Cerradao, a Brazilian hotspot of world biodiversity. Some trees were Cs accumulators, achieving mass fractions in leaves 700 times higher (up to 12.7 mg kg -1 ) when compared to other Brazilian native tree leaves from the Atlantic Forest. In fact, such trace element accumulation in leaves was not previously noticed for Brazilian ecosystems despite the intra- and inter-species variability observed in Cerrado tree leaves. (author)

  9. Occurrence of termites (Isoptera on living and standing dead trees in a tropical dry forest in Mexico

    Directory of Open Access Journals (Sweden)

    Nancy Calderón-Cortés

    2018-05-01

    Full Text Available Termites play a key role as ecosystem engineers in numerous ecological processes though their role in the dynamics of wood degradation in tropical dry forests, particularly at the level of the crown canopy, has been little studied. In this study, we analysed the occurrence of termites in the forest canopy by evaluating the density and proportion of living and standing dead trees associated with termites in deciduous and riparian habitats of the tropical dry forest in Chamela, Mexico. The results indicated that 60–98% of standing dead trees and 23–59% of living trees in Chamela were associated with termites. In particular, we found that the density of standing dead trees was higher in deciduous forests (0.057–0.066 trees/m2 than in riparian forests (0.022 and 0.027 trees/m2, even though the proportion of trees was not significantly different among habitats. Additionally, we found a higher density of trees associated with termites in trees of smaller size classes (0.01–0.09 trees/m2 than in larger class sizes (0–0.02 trees/m2. Interestingly, 72% of variation in the density of trees associated with termites is explained by the density of standing dead trees. Overall, these results indicate that standing dead tree availability might be the main factor regulating termite populations in Chamela forest and suggest that termites could play a key role in the decomposition of above-ground dead wood, mediating the incorporation of suspended and standing dead wood into the soil.

  10. Occurrence of termites (Isoptera) on living and standing dead trees in a tropical dry forest in Mexico.

    Science.gov (United States)

    Calderón-Cortés, Nancy; Escalera-Vázquez, Luis H; Oyama, Ken

    2018-01-01

    Termites play a key role as ecosystem engineers in numerous ecological processes though their role in the dynamics of wood degradation in tropical dry forests, particularly at the level of the crown canopy, has been little studied. In this study, we analysed the occurrence of termites in the forest canopy by evaluating the density and proportion of living and standing dead trees associated with termites in deciduous and riparian habitats of the tropical dry forest in Chamela, Mexico. The results indicated that 60-98% of standing dead trees and 23-59% of living trees in Chamela were associated with termites. In particular, we found that the density of standing dead trees was higher in deciduous forests (0.057-0.066 trees/m 2 ) than in riparian forests (0.022 and 0.027 trees/m 2 ), even though the proportion of trees was not significantly different among habitats. Additionally, we found a higher density of trees associated with termites in trees of smaller size classes (0.01-0.09 trees/m 2 ) than in larger class sizes (0-0.02 trees/m 2 ). Interestingly, 72% of variation in the density of trees associated with termites is explained by the density of standing dead trees. Overall, these results indicate that standing dead tree availability might be the main factor regulating termite populations in Chamela forest and suggest that termites could play a key role in the decomposition of above-ground dead wood, mediating the incorporation of suspended and standing dead wood into the soil.

  11. Minimum triplet covers of binary phylogenetic X-trees.

    Science.gov (United States)

    Huber, K T; Moulton, V; Steel, M

    2017-12-01

    Trees with labelled leaves and with all other vertices of degree three play an important role in systematic biology and other areas of classification. A classical combinatorial result ensures that such trees can be uniquely reconstructed from the distances between the leaves (when the edges are given any strictly positive lengths). Moreover, a linear number of these pairwise distance values suffices to determine both the tree and its edge lengths. A natural set of pairs of leaves is provided by any 'triplet cover' of the tree (based on the fact that each non-leaf vertex is the median vertex of three leaves). In this paper we describe a number of new results concerning triplet covers of minimum size. In particular, we characterize such covers in terms of an associated graph being a 2-tree. Also, we show that minimum triplet covers are 'shellable' and thereby provide a set of pairs for which the inter-leaf distance values will uniquely determine the underlying tree and its associated branch lengths.

  12. Introduction of deciduous fruit tree growing in the tropical highlands ...

    African Journals Online (AJOL)

    Mo

    have ever been conducted to investigate the potential of temperate tree fruits .... year-old apple cultivars at altitudes of 1830 and 2500 m.a.s.l while tables 2 and 3 ..... breaking are established in addition to determining the best fruiting season.

  13. Fulltext PDF

    Indian Academy of Sciences (India)

    Terminalia catappa L. (tropical almond) ofCombretaceae is a large handsome deciduous tree which branches in horizontal whorls. Leaves are simple and large which turn red before falling. Flowers are small, both bisexual and male, are borne in spike inflorescences. Fruits are ellipsoidal, slightly bilaterally compressed ...

  14. Polarimetric SAR Interferometry based modeling for tree height and aboveground biomass retrieval in a tropical deciduous forest

    Science.gov (United States)

    Kumar, Shashi; Khati, Unmesh G.; Chandola, Shreya; Agrawal, Shefali; Kushwaha, Satya P. S.

    2017-08-01

    The regulation of the carbon cycle is a critical ecosystem service provided by forests globally. It is, therefore, necessary to have robust techniques for speedy assessment of forest biophysical parameters at the landscape level. It is arduous and time taking to monitor the status of vast forest landscapes using traditional field methods. Remote sensing and GIS techniques are efficient tools that can monitor the health of forests regularly. Biomass estimation is a key parameter in the assessment of forest health. Polarimetric SAR (PolSAR) remote sensing has already shown its potential for forest biophysical parameter retrieval. The current research work focuses on the retrieval of forest biophysical parameters of tropical deciduous forest, using fully polarimetric spaceborne C-band data with Polarimetric SAR Interferometry (PolInSAR) techniques. PolSAR based Interferometric Water Cloud Model (IWCM) has been used to estimate aboveground biomass (AGB). Input parameters to the IWCM have been extracted from the decomposition modeling of SAR data as well as PolInSAR coherence estimation. The technique of forest tree height retrieval utilized PolInSAR coherence based modeling approach. Two techniques - Coherence Amplitude Inversion (CAI) and Three Stage Inversion (TSI) - for forest height estimation are discussed, compared and validated. These techniques allow estimation of forest stand height and true ground topography. The accuracy of the forest height estimated is assessed using ground-based measurements. PolInSAR based forest height models showed enervation in the identification of forest vegetation and as a result height values were obtained in river channels and plain areas. Overestimation in forest height was also noticed at several patches of the forest. To overcome this problem, coherence and backscatter based threshold technique is introduced for forest area identification and accurate height estimation in non-forested regions. IWCM based modeling for forest

  15. Flowering Trees

    Indian Academy of Sciences (India)

    Cassia siamia Lamk. (Siamese tree senna) of Caesalpiniaceae is a small or medium size handsome tree. Leaves are alternate, pinnately compound and glandular, upto 18 cm long with 8–12 pairs of leaflets. Inflorescence is axillary or terminal and branched. Flowering lasts for a long period from March to February. Fruit is ...

  16. Flowering Trees

    Indian Academy of Sciences (India)

    Flowering Trees. Cerbera manghasL. (SEA MANGO) of Apocynaceae is a medium-sized evergreen coastal tree with milky latex. The bark is grey-brown, thick and ... Fruit is large. (5–10 cm long), oval containing two flattened seeds and resembles a mango, hence the name Mangas or. Manghas. Leaves and fruits contain ...

  17. The leaf phenophase of deciduous species altered by land pavements

    Science.gov (United States)

    Chen, Yuanyuan; Wang, Xiaoke; Jiang, Bo; Li, Li

    2018-02-01

    It has been widely reported that the urban environment alters leaf and flowering phenophases; however, it remains unclear if land pavement is correlated with these alterations. In this paper, two popular deciduous urban trees in northern China, ash (Fraxinus chinensis) and maple (Acer truncatum), were planted in pervious and impervious pavements at three spacings (0.5 m × 0.5 m, 1.0 m × 1.0 m, and 2.0 m × 2.0 m apart). The beginning and end dates of the processes of leaf budburst and senescence were recorded in spring and fall of 2015, respectively. The results show that leaf budburst and senescence were significantly advanced in pavement compared to non-pavement lands. The date of full leaf budburst was earlier by 0.7-9.3 days for ash and by 0.3-2.3 days for maple under pavements than non-pavements, respectively. As tree spacing increases, the advanced days of leaf budburst became longer. Our results clearly indicate that alteration of leaf phenophases is attributed to land pavement, which should be taken into consideration in urban planning and urban plant management.

  18. Ectopic decidual reaction mimicking irritable bowel syndrome: a case report.

    Directory of Open Access Journals (Sweden)

    Soraya Salehgargari

    2014-01-01

    Full Text Available Ectopic decidualization with gross involvement of the peritoneum is one of the rare findings in pregnant women particularly when ectopic decidualization disseminated as an asymptomatic intra-abdominal nodule. We present here a case of an ectopic decidualization in a 33-year-old pregnant woman with symptoms of irritable bowel syndrome during pregnancy.

  19. Habitat selection by owls in a seasonal semi-deciduous forest in southern Brazil

    Directory of Open Access Journals (Sweden)

    W. Menq

    Full Text Available Abstract This paper tested the hypothesis that the structural components of vegetation have impact over the distribution of owl species in a fragment of a semi-deciduous seasonal forest. This paper also determined which vegetation variables contributed to the spatial distribution of owl species. It was developed in the Perobas Biological Reserve (PBR between September and December 2011. To conduct the owl census, a playback technique was applied at hearing points distributed to cover different vegetation types in the study area. A total of 56 individual owls of six species were recorded: Tropical Screech-Owl (Megascops choliba, Black-capped Screech-Owl (Megascops atricapilla, Tawny-browed Owl (Pulsatrix koeniswaldiana, Ferruginous Pygmy-Owl (Glaucidium brasilianum, Mottled Owl (Strix virgata and Stygian Owl (Asio stygius. The results suggest that the variables of vegetation structure have impact on the occurrence of owls. The canopy height, the presence of hollow trees, fallen trees and glades are the most important structural components influencing owl distribution in the sampled area.

  20. A comparison of 137Cs radioactivity in localized evergreen and deciduous plant species

    International Nuclear Information System (INIS)

    Rangel, R.C.

    1996-05-01

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

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

    Directory of Open Access Journals (Sweden)

    Ashish K Mishra

    2013-12-01

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

  2. Deciduous birch canopy as unexpected contributor to stand level atmospheric reactivity in boreal forests

    Science.gov (United States)

    Bäck, Jaana; Taipale, Ditte; Aalto, Juho

    2017-04-01

    In boreal forests, deciduous trees such as birches may in future climate become more abundant due to their large biomass production capacity, relatively good resource use ability and large acclimation potential to elevated CO2 levels and warmer climate. Increase in birch abundance may lead to unpredicted consequences in atmospheric composition. Currently it is acknowledged that conifers such as Scots pine and Norway spruce are important sources for volatile organic compounds (VOCs), especially monoterpenes, throughout the year, although the strong temperature relationships implies that emissions are highest in summertime. However, the dynamics of the deciduous birch foliage VOC emissions and their relationship with environmental drivers during the development, maturation and senescence of foliage has not been well analyzed. Long-term measurements of birch, which are unfortunately very sparse, can provide very useful information for the development of biosphere-atmosphere models that simulate boreal and subarctic forested areas where birch is often a sub-canopy species, occurs as a mixture among conifers or forms even pure stands in the higher latitudes. We measured the branch level VOC emissions from a mature Silver birch with proton transfer reaction mass spectrometer during 2014 and 2015 at the SMEAR II station (Station for Measuring Ecosystem-Atmosphere Relations), southern Finland. Our results showed that the Silver birch foliage is a huge source for both short-chained volatiles such as methanol, acetaldehyde and acetone, as well as for monoterpenes. The mean emission rates from birch leaves were 5 to 10 times higher than the corresponding emissions from Scots pine shoots. We compared several semi-empirical model approaches for determining the birch foliage monoterpene standardized emission potentials, and utilized the continuous emission measurements from the two growing seasons for development of a novel algorithm which accounts for the leaf development and

  3. Evaluation of Antinociceptive Activity of Ethanol Extract of Leaves of Adenanthera pavonina

    Directory of Open Access Journals (Sweden)

    Md. Moniruzzaman

    2015-01-01

    Full Text Available Adenanthera pavonina is a deciduous tree commonly used in the traditional medicine to treat inflammation and rheumatism. The aim of this study was to evaluate the antinociceptive activity of ethanol extract of leaves of A. pavonina (EEAP. EEAP was investigated using various nociceptive models induced thermally or chemically in mice including hot plate and tail immersion test, acetic acid-induced writhing, and glutamate- and formalin-induced licking tests at the doses of 50, 100, and 200 mg/kg body weight (p.o.. In addition, to assess the possible mechanisms, involvement of opioid system was verified using naloxone (2 mg/kg and cyclic guanosine monophosphate (cGMP signaling pathway by methylene blue (MB; 20 mg/kg. The results have demonstrated that EEAP produced a significant and dose-dependent increment in the hot plate latency and tail withdrawal time. It also reduced the number of abdominal constrictions and paw lickings induced by acetic acid and glutamate respectively. EEAP inhibited the nociceptive responses in both phases of formalin test. Besides, the reversal effects of naloxone indicated the association of opioid receptors on the exertion of EEAP action centrally. Moreover, the enhancement of writhing inhibitory activity by MB suggests the possible involvement of cGMP pathway in EEAP-mediated antinociception. These results prove the antinociceptive activity of the leaves of A. pavonina and support the traditional use of this plant.

  4. Flowering Trees

    Indian Academy of Sciences (India)

    medium-sized handsome tree with a straight bole that branches at the top. Leaves are once pinnate, with two to three pairs of leaflets. Young parts of the tree are velvety. Inflorescence is a branched raceme borne at the branch ends. Flowers are large, white, attractive, and fragrant. Corolla is funnel-shaped. Fruit is an ...

  5. Flowering Trees

    Indian Academy of Sciences (India)

    Srimath

    Grevillea robusta A. Cunn. ex R. Br. (Sil- ver Oak) of Proteaceae is a daintily lacy ornamental tree while young and growing into a mighty tree (45 m). Young shoots are silvery grey and the leaves are fern- like. Flowers are golden-yellow in one- sided racemes (10 cm). Fruit is a boat- shaped, woody follicle.

  6. Rate of tree carbon accumulation increases continuously with tree size.

    Science.gov (United States)

    Stephenson, N L; Das, A J; Condit, R; Russo, S E; Baker, P J; Beckman, N G; Coomes, D A; Lines, E R; Morris, W K; Rüger, N; Alvarez, E; Blundo, C; Bunyavejchewin, S; Chuyong, G; Davies, S J; Duque, A; Ewango, C N; Flores, O; Franklin, J F; Grau, H R; Hao, Z; Harmon, M E; Hubbell, S P; Kenfack, D; Lin, Y; Makana, J-R; Malizia, A; Malizia, L R; Pabst, R J; Pongpattananurak, N; Su, S-H; Sun, I-F; Tan, S; Thomas, D; van Mantgem, P J; Wang, X; Wiser, S K; Zavala, M A

    2014-03-06

    Forests are major components of the global carbon cycle, providing substantial feedback to atmospheric greenhouse gas concentrations. Our ability to understand and predict changes in the forest carbon cycle--particularly net primary productivity and carbon storage--increasingly relies on models that represent biological processes across several scales of biological organization, from tree leaves to forest stands. Yet, despite advances in our understanding of productivity at the scales of leaves and stands, no consensus exists about the nature of productivity at the scale of the individual tree, in part because we lack a broad empirical assessment of whether rates of absolute tree mass growth (and thus carbon accumulation) decrease, remain constant, or increase as trees increase in size and age. Here we present a global analysis of 403 tropical and temperate tree species, showing that for most species mass growth rate increases continuously with tree size. Thus, large, old trees do not act simply as senescent carbon reservoirs but actively fix large amounts of carbon compared to smaller trees; at the extreme, a single big tree can add the same amount of carbon to the forest within a year as is contained in an entire mid-sized tree. The apparent paradoxes of individual tree growth increasing with tree size despite declining leaf-level and stand-level productivity can be explained, respectively, by increases in a tree's total leaf area that outpace declines in productivity per unit of leaf area and, among other factors, age-related reductions in population density. Our results resolve conflicting assumptions about the nature of tree growth, inform efforts to undertand and model forest carbon dynamics, and have additional implications for theories of resource allocation and plant senescence.

  7. Trees as indicators of subterranean migration of tritium at a commercial shallow land radioactive waste disposal site

    International Nuclear Information System (INIS)

    Rickard, W.H.; Kirby, L.J.

    1984-09-01

    Leaf water and tree sap collected from deciduous trees in a natural forest growing outside the fenced exclusion area of the Maxey Flats Waste Disposal Facility in eastern Kentucky, USA were radiochemically analyzed to detect movement of tritium via subterranean flows of water at depths of three meters. These data indicate that trees can be used to detect the subterranean migration of tritium from shallow land burial sites. 4 references, 5 figures, 1 table

  8. Trees as indicators of subterranean water flow from a retired radioactive waste disposal site

    International Nuclear Information System (INIS)

    Rickard, W.H.; Kirby, L.J.

    1987-01-01

    Tree sampling helped locate a subterranean flow of tritiated water from a low-level radioactive waste disposal site that had not been detected by well water monitoring alone. Deciduous trees growing in a natural forest on the hillsides downslope from the site were sampled for the presence of tritiated water in sap of maple trees and in leaf water extracted from oak and hickory trees. Elevated concentrations of 3 H were detected in the leaf water extracted from several trees located 50 m downslope from the western boundary of the fenced exclusion zone. A 3-m-deep well drilled near these trees indicated that the source of tritiated water was a narrow zone of subterranean flow

  9. Salinity guidelines for irrigation: Case studies from Water Research ...

    African Journals Online (AJOL)

    the entire fruit and wine industries are dependent on irrigation. Cropping in the Eastern and Northern Cape also relies heavily on irrigation. ..... The soils were described as deep, fine sandy, dominantly red, ..... crops. For example, leaves of deciduous fruit trees (apri- ..... Laboratory Handbook 60, USDA, Washington. 160 pp.

  10. Leptopelis boulengeri, Hyperolius fusciventris bourtoni, H. guttulatus

    African Journals Online (AJOL)

    Fumnanya

    Majority of H. guttulatus occupied leaves of shrubs and trees between 0.7-1.6m and a ... Southeastern (Cross River National Park and. Obudu Plateau) ..... as the savanna, deciduous forest and derived savanna .... December 1999, Washington D.C.. (Conservation ... (Anura: Hyperoliidae) in south-eastern Ivory. Coast, with ...

  11. Time-dependent effects of climate and drought on tree growth in a Neotropical dry forest: Short-term tolerance vs. long-term sensitivity

    NARCIS (Netherlands)

    Mendivelso, H.A.; Camarero, J.J.; Gutierrez, E.; Zuidema, P.

    2014-01-01

    We analyzed the effects of climate and drought on radial growth using dendrochronology in seven deciduous tree species coexisting in a Bolivian tropical dry forest subjected to seasonal drought. Precipitation, temperature and a multiscalar drought index were related to tree-ring width data at

  12. Investigating and modeling the pyrolysis kinetic of leaves and stems of pistachio trees for biofuel production

    Directory of Open Access Journals (Sweden)

    M Ostad Hoseini

    2016-09-01

    Full Text Available Introduction The lignocelluloses materials have high potential for producing various types of biofuels. These materials include various parts of plants, especially leaves and stems that are left without a specific usage after annual pruning. These residues can be used through slow or fast pyrolysis process for production of liquid and gaseous biofuels. The slow pyrolysis is taking place at temperatures below 500°C while fast pyrolysis process takes place at a temperature above 700°C. Various studies on production of biofuels from plant residues have shown that the temperature, heating rate and the resident time of pyrolysis process are the main factors that affect the final product quality. At present time, in Iran, there are more than 360 thousands hectares of pistachio growing fields which annually produce over 215 thousands metric tons residues which are mainly leaves and stems. The main objective of this study was to measure the heating properties of the powders prepared from the leaves and the stem of pistachio trees. These properties include higher heating value (HHV, lower heating value (LHV and thermal gravimetric analysis (TGA of the powders. Then the powders were separately pyrolysed and the kinetic of the pyrolysis process for producing charcoal from them was investigated. Materials and Methods In this research, leaves and stems of pistachio trees were initially analyzed to determine their chemical constituents including moisture content, volatile compounds, carbon (C, hydrogen (H, nitrogen (N, sulfur (S and oxygen (O content. Using these constituents the height heating value and low heating value for the leaves and the stems were determined. The thermal gravimetric analysis (TGA of the powders was made to select a proper heating temperature for pyrolysis of the powders. In each experiment about 10 g of powder powders were pyrolyzed to produce char. Based on TGA results, the pyrolysis experiments were performed at 350, 400, 450 and

  13. Mechanisms of copper stress alleviation in Citrus trees after metal uptake by leaves or roots.

    Science.gov (United States)

    Hippler, Franz Walter Rieger; Petená, Guilherme; Boaretto, Rodrigo Marcelli; Quaggio, José Antônio; Azevedo, Ricardo Antunes; Mattos-Jr, Dirceu

    2018-05-01

    Nutritional disorders caused by copper (Cu) have affected citrus orchards. Since Cu is foliar sprayed as a pesticide to control citrus diseases, this metal accumulates in the soil. Thereby, we evaluated the effects of Cu leaf absorption after spray of different metal sources, as well as roots absorption on growth, nutritional status, and oxidative stress of young sweet orange trees. Two experiments were carried out under greenhouse conditions. The first experiment was set up with varying Cu levels to the soil (nil Cu, 0.5, 2.0, 4.0 and 8.0 g of Cu per plant as CuSO 4 .5H 2 O), whereas the second experiment with Cu application via foliar sprays (0.5 and 2.0 g of Cu per plant) and comparing two metal sources (CuSO 4 .5H 2 O or Cu(OH) 2 ). Copper was mainly accumulated in roots with soil supply, but an increase of oxidative stress levels was observed in leaves. On the other hand, Cu concentrations were higher in leaves that received foliar sprays, mainly as Cu(OH) 2 . However, when sulfate was foliar sprayed, plants exhibited more symptoms of injuries in the canopy with decreased chlorophyll contents and increased hydrogen peroxide and lipid peroxidation levels. Copper toxicity was characterized by sap leakage from the trunk and twigs, which is the first report of this specific Cu excess symptom in woody trees. Despite plants with 8.0 g of Cu soil-applied exhibiting the sap leakage, growth of new plant parts was more vigorous with lower oxidative stress levels and injuries compared to those with 4.0 g of Cu soil-applied (without sap leakage). With the highest level of Cu applied via foliar as sulfate, Cu was eliminated by plant roots, increasing the rhizospheric soil metal levels. Despite citrus likely exhibiting different mechanisms to reduce the damages caused by metal toxicity, such as responsive enzymatic antioxidant system, metal accumulation in the roots, and metal exclusion by roots, excess Cu resulted in damages on plant growth and metabolism when the

  14. Multiple-purpose trees for pastoral farming in New Zealand: with emphasis on tree legumes. [Lucerne Tree: Medick Tree

    Energy Technology Data Exchange (ETDEWEB)

    Davies, D J.G.; Macfarlane, R P

    1979-01-01

    The potential for soil conservation and agroforestry of several native and exotic legumes is discussed. Flowering period, chemical composition of leaves/pods, hardiness to frost and drought, timber value, forage potential for livestock and bees, ornamental value and other products are tabulated with information on up to 38 species. Two low-growing species that have proved useful for slope stabilization as well as forage are tree lucerne (Cytisus palmensis) and tree medick (Medicago arborea), the latter being shrubby and more suitable for cold districts. Gleditsia triacanthos is recommended as a shade and fodder tree for farm pasture.

  15. Rate of tree carbon accumulation increases continuously with tree size

    Science.gov (United States)

    Stephenson, N.L.; Das, A.J.; Condit, R.; Russo, S.E.; Baker, P.J.; Beckman, N.G.; Coomes, D.A.; Lines, E.R.; Morris, W.K.; Rüger, N.; Álvarez, E.; Blundo, C.; Bunyavejchewin, S.; Chuyong, G.; Davies, S.J.; Duque, Á.; Ewango, C.N.; Flores, O.; Franklin, J.F.; Grau, H.R.; Hao, Z.; Harmon, M.E.; Hubbell, S.P.; Kenfack, D.; Lin, Y.; Makana, J.-R.; Malizia, A.; Malizia, L.R.; Pabst, R.J.; Pongpattananurak, N.; Su, S.-H.; Sun, I-F.; Tan, S.; Thomas, D.; van Mantgem, P.J.; Wang, X.; Wiser, S.K.; Zavala, M.A.

    2014-01-01

    Forests are major components of the global carbon cycle, providing substantial feedback to atmospheric greenhouse gas concentrations. Our ability to understand and predict changes in the forest carbon cycle—particularly net primary productivity and carbon storage - increasingly relies on models that represent biological processes across several scales of biological organization, from tree leaves to forest stands. Yet, despite advances in our understanding of productivity at the scales of leaves and stands, no consensus exists about the nature of productivity at the scale of the individual tree, in part because we lack a broad empirical assessment of whether rates of absolute tree mass growth (and thus carbon accumulation) decrease, remain constant, or increase as trees increase in size and age. Here we present a global analysis of 403 tropical and temperate tree species, showing that for most species mass growth rate increases continuously with tree size. Thus, large, old trees do not act simply as senescent carbon reservoirs but actively fix large amounts of carbon compared to smaller trees; at the extreme, a single big tree can add the same amount of carbon to the forest within a year as is contained in an entire mid-sized tree. The apparent paradoxes of individual tree growth increasing with tree size despite declining leaf-level and stand-level productivity can be explained, respectively, by increases in a tree’s total leaf area that outpace declines in productivity per unit of leaf area and, among other factors, age-related reductions in population density. Our results resolve conflicting assumptions about the nature of tree growth, inform efforts to understand and model forest carbon dynamics, and have additional implications for theories of resource allocation and plant senescence.

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

    Science.gov (United States)

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

    2018-04-01

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

  17. Leaf gas exchange in the frankincense tree (Boswellia papyrifera) of African dry woodlands

    NARCIS (Netherlands)

    Mengistu, T.; Sterck, F.J.; Fetene, M.; Tadesse, W.; Bongers, F.

    2011-01-01

    A conceptual model was tested for explaining environmental and physiological effects on leaf gas exchange in the deciduous dry tropical woodland tree Boswellia papyrifera (Del.) Hochst. For this species we aimed at (i) understanding diurnal patterns in leaf gas exchange, (ii) exploring cause–effect

  18. 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.

  19. Hg contents in soils and olive-tree (Olea Europea, L.) leaves from an area affected by elemental mercury pollution (Jódar, SE Spain).

    Science.gov (United States)

    López-Berdonces, Miguel Angel; María Esbrí, José; Amorós, José Angel; Lorenzo, Saturnino; Fernández-Calderón, Sergio; Higueras, Pablo; Perez-de-los-Reyes, Caridad

    2014-05-01

    Data from soil and olive tree leaves around a decommissioned chlor-alkali plant are presented in this communication. The factory was active in the period 1977-1991, producing during these years a heavily pollution of Guadalquivir River and hydrargyrism in more than local 45 workers. It is located at 7 km South of Jódar, a locality with some 12,120 inhabitants. Mercury usage was general in this type of plants, but at present it is being replaced by other types of technologies, due to the risks of mercury usage in personal and environment. A soil geochemistry survey was carried out in the area, along with the analysis of olive-tree leaves (in the plots with this culture) from the same area. 73 soil samples were taken at two different depths (0-15 cm and 15-30 cm), together with 41 olive tree samples. Mercury content of geologic and biologic samples was determined by means of Atomic Absorption Spectrometry with Zeeman Effect, using a Lumex RA-915+ device with the RP-91C pyrolysis attachment. Air surveys were carried our using a RA-915M Lumex portable analytical device. Soil mercury contents were higher in topsoil than in the deeper soil samples, indicating that incorporation of mercury was due to dry and wet deposition of mercury vapors emitted from the plant. Average content in topsoil is 564.5 ng g-1. Hg contents in olive-tree leaves were in the range 46 - 453 ng g-1, with an average of 160.6 ng g-1. This level is slightly lower than tolerable level for agronomic crops established by Kabata-Pendias (2001) in 200 ng g-1. We have also compared soil and leaf contents for each sampling site, finding a positive and significant correlation (R=0.49), indicating that Hg contents in the leaves are linked to Hg contents in the soils. BAC (Bioaccumulation Absorption Coefficient, calculated as ratio between soil and leaf concentration) is 0.28 (consistent with world references, BAC = 0.7), considered "medium" in comparison with other mineral elements. Main conclusions of this

  20. The Influence of DEM Quality on Mapping Accuracy of Coniferous- and Deciduous-Dominated Forest Using TerraSAR‑X Images

    Directory of Open Access Journals (Sweden)

    Gerald Kändler

    2012-03-01

    Full Text Available Climate change is a factor that largely contributes to the increase of forest areas affected by natural damages. Therefore, the development of methodologies for forest monitoring and rapid assessment of affected areas is required. Space-borne synthetic aperture radar (SAR imagery with high resolution is now available for large-scale forest mapping and forest monitoring applications. However, a correct interpretation of SAR images requires an adequate preprocessing of the data consisting of orthorectification and radiometric calibration. The resolution and quality of the digital elevation model (DEM used as reference is crucial for this purpose. Therefore, the primary aim of this study was to analyze the influence of the DEM quality used in the preprocessing of the SAR data on the mapping accuracy of forest types. In order to examine TerraSAR-X images to map forest dominated by deciduous and coniferous trees, High Resolution SpotLight images were acquired for two study sites in southern Germany. The SAR images were preprocessed with a Shuttle Radar Topography Mission (SRTM DEM (resolution approximately 90 m, an airborne laser scanning (ALS digital terrain model (DTM (5 m resolution, and an ALS digital surface model (DSM (5 m resolution. The orthorectification of the SAR images using high resolution ALS DEMs was found to be important for the reduction of errors in pixel location and to increase the classification accuracy of forest types. SAR images preprocessed with ALS DTMs resulted in the highest classification accuracies, with kappa coefficients of 0.49 and 0.41, respectively. SAR images preprocessed with ALS DTMs resulted in greater accuracy than those preprocessed with ALS DSMs in most cases. The classification accuracy of forest types using SAR images preprocessed with the SRTM DEM was fair, with kappa coefficients of 0.23 and 0.32, respectively.Analysis of the radar backscatter indicated that sample plots dominated by coniferous trees

  1. miRNA signature and Dicer requirement during human endometrial stromal decidualization in vitro.

    Directory of Open Access Journals (Sweden)

    Carlos Estella

    Full Text Available Decidualization is a morphological and biochemical transformation of endometrial stromal fibroblast into differentiated decidual cells, which is critical for embryo implantation and pregnancy establishment. The complex regulatory networks have been elucidated at both the transcriptome and the proteome levels, however very little is known about the post-transcriptional regulation of this process. miRNAs regulate multiple physiological pathways and their de-regulation is associated with human disorders including gynaecological conditions such as endometriosis and preeclampsia. In this study we profile the miRNAs expression throughout human endometrial stromal (hESCs decidualization and analyze the requirement of the miRNA biogenesis enzyme Dicer during this process. A total of 26 miRNAs were upregulated and 17 miRNAs downregulated in decidualized hESCs compared to non-decidualized hESCs. Three miRNAs families, miR-181, miR-183 and miR-200, are down-regulated during the decidualization process. Using miRNAs target prediction algorithms we have identified the potential targets and pathways regulated by these miRNAs. The knockdown of Dicer has a minor effect on hESCs during in vitro decidualization. We have analyzed a battery of decidualization markers such as cell morphology, Prolactin, IGFBP-1, MPIF-1 and TIMP-3 secretion as well as HOXA10, COX2, SP1, C/EBPß and FOXO1 expression in decidualized hESCs with decreased Dicer function. We found decreased levels of HOXA10 and altered intracellular organization of actin filaments in Dicer knockdown decidualized hESCs compared to control. Our results provide the miRNA signature of hESC during the decidualization process in vitro. We also provide the first functional characterization of Dicer during human endometrial decidualization although surprisingly we found that Dicer plays a minor role regulating this process suggesting that alternative biogenesis miRNAs pathways must be involved in human

  2. Fulltext PDF

    Indian Academy of Sciences (India)

    (Colville's glory) of Leguminosae is a medium size deciduous tree with a thin coppery bark and slender feathery canopy. Leaves are twice compound bearing many leaflets. Flowers are fiery orange-red and produced on long drooping inflorescence. Stamens are longer than the corolla and are exserted. Fruit is a cylindrical ...

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

    Energy Technology Data Exchange (ETDEWEB)

    Rangel, R.C.

    1996-05-01

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

  4. Influences of Forest Tree Species and Early Spring Temperature on Surface-Atmosphere Transfers of Water and Carbon in the Northeastern U.S.

    Science.gov (United States)

    Hadley, J. L.; Kuzeja, P.; Mulcahy, T.; Singh, S.

    2008-12-01

    Influences of Forest Tree Species and Early Spring Temperature on Surface-Atmosphere Transfers of Water and Carbon in the Northeastern U.S. Julian Hadley, Paul Kuzeja, Safina Singh and Thomas Mulcahy Transfers of water vapor from terrestrial ecosystems to the atmosphere affect regional hydrology, weather and climate over short time scales, and forest-atmosphere CO2 exchange affects global climate over long timescales. To better understand these effects for forests dominated by two very different tree species, we measured forest-atmosphere water vapor and CO2 transfers by the eddy flux technique to at two sites in central Massachusetts USA for three years. Average annual evapotranspiration (ET) for a young deciduous forest dominated by red oak (Quercus rubra L., the most abundant tree species in the area), was about 430 mm or 25 percent greater than for a coniferous forest dominated by 100 to 230 year old eastern hemlock (Tsuga canadensis L.). The difference in ET was most pronounced in July and August when the deciduous forest lost about 50 percent more water by ET in the average year (192 mm for oak forest versus 130 mm for hemlock). These data indicate that if deciduous trees with similar physiology to red oak replace hemlocks, summertime ET will increase while summer streamflow, soil water content and the extent of year- round wetlands will decrease. Increased summertime ET should also lead to slightly higher regional atmospheric humidity and precipitation. Hemlock-to-deciduous forest conversion has occurred from North Carolina to southern New England and is continuing northward as a lethal insect pest, the hemlock woolly adelgid (Adelges tsugae Annand) continues to kill hemlocks. Average annual carbon storage for the old hemlock forest in our study was about 3.3 Mg C/ha, nearly equal to the average for the deciduous forest, 3.5 Mg C/ha. This calls into question ecological theory that predicts large declines in the rate of carbon uptake for old forests, and

  5. The diversity of polyprenol pattern in leaves of fruit trees belonging to Rosaceae and Cornaceae.

    Science.gov (United States)

    Wanke, M; Chojnacki, T; Swiezewska, E

    1998-01-01

    The polyprenol pattern in leaves of fruit trees belonging to the Rosaceae (genera: Prunus, Malus) and Cornaceae (genus: Cornus) families is presented. The content of polyprenyl acetates varied within plant species between 10-50 mg per gram of dry weight. In genus Prunus, Cornus and in representatives of species Malus domestica, a mixture of polyprenols composed of 18, 19, 20, 21 isoprene units was found. In six species of genus Prunus (sour-cherry): P. serrulata-spontanea, P. yedoensis, P. fruticosa. P. kurilensis, P. subhirtella and P. incisa the presence of a second polyprenol family, i.e. the group of prenologues consisting of prenol -35, -36, -37, etc. up to -42 was detected.

  6. Interannual variability in the extent and intensity of tropical dry forest deciduousness in the Mexican Yucatan (2000-2016): Drivers and Links to Regional Atmospheric Conditions

    Science.gov (United States)

    Cuba, Nicholas Joseph

    The dry topical forests of the southern Yucatan Peninsula experience multiple natural and anthropogenic disturbances, as well as substantial interannual climate variability that can result in stark interannual differences in vegetation phenology. Dry season deciduousness is a typical response to limit tree water loss during prolonged periods of hot and dry conditions, and this behavior has both direct implications for ecosystem functioning, and the potential to indicate climate conditions when observed using remotely-sensed data. The first research paper of this dissertation advances methods to assess the accuracy of remotely-sensed measurements of canopy conditions using in-situ observations. Linear regression models show the highest correlation (R2 = 0.751) between in-situ canopy gap fraction and Landsat NDWISWIR2. MODIS time series NDWISWIR2 are created for the period March 2000-February 2011, and exhibit stronger correlation with time series of TRMM precipitation data than do MODIS EVI time series (R2= 0.48 vs. R2 = 0.43 in deciduous forest areas). The second paper examines differences between the deciduous phenology of young forest stands and older forest stands. Land-cover maps are overlaid to determine whether forested areas are greater than or less than 22 years old in 2010, and metrics related to deciduous phenology are derived from MODIS EVI2 time series in three years, 2008 to 2011. Statistical tests that compare matched pairs of young (12-22 years) and older (>22 years) forest stand age class samples are used to detect significant differences in metrics related to the intensity and timing of deciduousness. In all three years, younger forests exhibit significantly more intense deciduousness, measured as total seasonal change of EVI2 normalized by annual maximum EVI2 (pmediating environmental factors that drive the spatial and temporal variability in the intensity of deciduousness, and point toward analyzing deciduousness to reveal information about other

  7. Increased accumulation of cuticular wax and expression of lipid transfer protein in response to periodic drying events in leaves of tree tobacco.

    Science.gov (United States)

    Cameron, Kimberly D; Teece, Mark A; Smart, Lawrence B

    2006-01-01

    Cuticular wax deposition and composition affects drought tolerance and yield in plants. We examined the relationship between wax and dehydration stress by characterizing the leaf cuticular wax of tree tobacco (Nicotiana glauca L. Graham) grown under periodic dehydration stress. Total leaf cuticular wax load increased after each of three periods of dehydration stress using a CH2Cl2 extraction process. Overall, total wax load increased 1.5- to 2.5-fold, but composition of the wax was not altered. Homologous series of wax components were classified into organic groups; n-hentriacontane was the largest component (>75%) with alcohols and fatty acids representing drying event. Leaves excised from plants subjected to multiple drying events were more resistant to water loss compared to leaves excised from well-watered plants, indicating that there is a negative relationship between total wax load and epidermal conductance. Lipid transfer proteins (LTPs) are thought to be involved in the transfer of lipids through the extracellular matrix for the formation of cuticular wax. Using northern analysis, a 6-fold increase of tree tobacco LTP gene transcripts was observed after three drying events, providing further evidence that LTP is involved in cuticle deposition. The simplicity of wax composition and the dramatic wax bloom displayed by tree tobacco make this an excellent species in which to study the relationship between leaf wax deposition and drought tolerance.

  8. Bone marrow origin of decidual cell precursors in the pseudopregnant mouse uterus

    International Nuclear Information System (INIS)

    Kearns, M.; Lala, P.K.

    1982-01-01

    Decidual cells are considered to be the endproduct of a hormonally induced transformation of endometrial stromal cells of the uterus. However, the source of these precursors remains unknown. This study of evaluated the possibility of their bone marrow origin by an examination of the H-2 phenotype of decidual cells in pseudopregnant bone marrow chimeras. These chimeras were produced by repopulating lethally irradiated CBA/J female (H-2k) mice with bone marrow from (CBA/J x C57BL/6J) F1 female (H-2kb) mice. Pseudopregnancy was produced with a hormonal regimen followed by an oil-induced decidual stimulus. Chimerism was evaluated radioautographically by an identification of the donor-specific Kb phenotype on cells with an immunolabeling technique with monospecific anti-H-2 serum followed by radioiodinated protein A. The extent of chimerism as indicated by the degree of Kb labeling on decidual cells as well as macrophages contained within the decidual nodules was quantitatively compared with that seen on splenic lymphocytes. Fair to good chimerism, as reflected by labeling for the donor-specific marker (Kb), was seen on splenic lymphocytes and macrophages within the decidual nodules in 6 out of 11 animals. A similar level of chimerism was detected on decidual cells in all but one of these six, in which case this was low. One animal showed low chimerism in the spleen but good chimerism on the decidual cells. The remaining four mice were nonchimeric for all three cell types. These results indicate that decidual cells and macrophages appearing within the decidual nodules of pseudopregnant mice are ultimate descendants of bone marrow cells

  9. Tree age-dependent changes in photosynthetic and respiratory CO2 exchange in leaves of micropropagated diploid, triploid and hybrid aspen.

    Science.gov (United States)

    Pärnik, Tiit; Ivanova, Hiie; Keerberg, Olav; Vardja, Rael; Niinemets, Ulo

    2014-06-01

    The growth rate of triploid European aspen (Populus tremula L.) and hybrid aspen (P. tremula × Populus tremuloides Michx.) significantly exceeds that of diploid aspen, but the underlying physiological controls of the superior growth rates of these genotypes are not known. We tested the hypothesis that the superior growth rate of triploid and hybrid aspen reflects their greater net photosynthesis rate. Micropropagated clonal plants varying in age from 2.5 to 19 months were used to investigate the ploidy and plant age interaction. The quantum yield of net CO2 fixation (Φ) in leaves of young 2.5-month-old hybrid aspen was lower than that of diploid and triploid trees. However, Φ in 19-month-old hybrid aspen was equal to that in triploid aspen and higher than that in diploid aspen. Φ and the rate of light-saturated net photosynthesis (ANS) increased with plant age, largely due to higher leaf dry mass per unit area in older plants. ANS in leaves of 19-month-old trees was highest in hybrid, medium in triploid and lowest in diploid aspen. Light-saturated photosynthesis had a broad temperature optimum between 20 and 35 °C. Rate of respiration in the dark (RDS) did not vary among the genotypes in 2.5-month-old plants, and the shape of the temperature response was also similar. RDS increased with plant age, but RDS was still not significantly different among the leaves of 19-month-old diploid and triploid aspen, but it was significantly lower in leaves of 19-month-old hybrid plants. The initial differences in the growth of plants with different ploidy were minor up to the age of 19 months, but during the next 2 years, the growth rate of hybrid aspen exceeded that of triploid plants by 2.7 times and of diploid plants by five times, in line with differences in ANS of 19-month-old plants of these species. It is suggested that differences in photosynthesis and growth became more pronounced with tree aging, indicating that ontogeny plays a key role in the expression of

  10. A compartment model of plutonium dynamics in a deciduous forest ecosystem

    International Nuclear Information System (INIS)

    Garten, C.T. Jr.; Gardner, R.H.; Dahlman, R.C.

    1978-01-01

    A linear compartment donor-controlled model was designed to describe and simulate the behaviour of plutonium ( 239 , 240 Pu) in a contaminated deciduous forest ecosystem at Oak Ridge, Tennessee. At steady states predicted by the model, less than 0.25% of the Pu in the ecosystem resides in forest biota. Soil is the major repository of Pu in the forest, and reciprocal exchanges of Pu between soil and litter or soil and tree roots were dominant transfers affecting the ecosystem distribution of Pu. Variation in predicted steady state amounts of Pu in the forest, given variability in the model parameters, indicated that ones ability to develop reliable models of Pu transport in ecosystems will improve with greater precision in data from natural environments and a better understanding of sources of variation in Pu data. (author)

  11. Anchoring quartet-based phylogenetic distances and applications to species tree reconstruction.

    Science.gov (United States)

    Sayyari, Erfan; Mirarab, Siavash

    2016-11-11

    Inferring species trees from gene trees using the coalescent-based summary methods has been the subject of much attention, yet new scalable and accurate methods are needed. We introduce DISTIQUE, a new statistically consistent summary method for inferring species trees from gene trees under the coalescent model. We generalize our results to arbitrary phylogenetic inference problems; we show that two arbitrarily chosen leaves, called anchors, can be used to estimate relative distances between all other pairs of leaves by inferring relevant quartet trees. This results in a family of distance-based tree inference methods, with running times ranging between quadratic to quartic in the number of leaves. We show in simulated studies that DISTIQUE has comparable accuracy to leading coalescent-based summary methods and reduced running times.

  12. Significance, prospects and limits of breeding smoke-resistant tree species in the light of central European studies on the ecological effects of fumes

    Energy Technology Data Exchange (ETDEWEB)

    Wentzel, K F

    1967-01-01

    Damage to tree stands in central Europe from atmospheric pollution will become more extensive with time, thus, the breeding of pollution-resistant tree species assumes increasing importance. Since no differences in resistance could be detected in individual pine trees by experiments, interest focused on spruce trees where such differences exist and were proven. But no spruce specimens were ever found which in resistance would have surpassed deciduous trees, whose regenerative power is a factor governing their considerable resistance to damge from pollution. Resistant spruce specimens were found to have comparatively massive needles, which also applies to other species of conifers. Thus there seems to be a connection between the anatomical structure of the needles and their degree of of hardiness in a polluted atmosphere. Breeding of relatively resistant spruce trees by selection was started in 1956 and the first planting experiments in polluted areas were carried out in 1960. This work is of great importance for the reafforestation of approximately 100,000 hectares h of forests in central Europe which are affected by chronic damage from pollution. Resistant spruce trees, under conditions of a mildly polluted atmosphere, should produce for 20 years longer than less resistant strains. In areas exposed to severe pollution, only deciduous trees should be planted.

  13. Influence of Immigration on Epiphytic Bacterial Populations on Navel Orange Leaves

    OpenAIRE

    Lindow, S. E.; Andersen, G. L.

    1996-01-01

    Factors that influenced the increase in epiphytic bacterial population size on navel orange leaves during winter months were investigated to test the assumption that such populations were the result of multiplication on orange leaves. The population sizes of bacteria of different kinds, including ice nucleation-active (Ice(sup+)) bacteria, were from 6- to 30-fold larger on leaves of navel orange trees adjacent to other plant species than on trees growing near other citrus species. Total and I...

  14. Contrasting ozone sensitivity in related evergreen and deciduous shrubs

    International Nuclear Information System (INIS)

    Calatayud, Vicent; Marco, Francisco; Cervero, Julia; Sanchez-Pena, Gerardo; Sanz, Maria Jose

    2010-01-01

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

  15. Comparing Individual Tree Segmentation Based on High Resolution Multispectral Image and Lidar Data

    Science.gov (United States)

    Xiao, P.; Kelly, M.; Guo, Q.

    2014-12-01

    This study compares the use of high-resolution multispectral WorldView images and high density Lidar data for individual tree segmentation. The application focuses on coniferous and deciduous forests in the Sierra Nevada Mountains. The tree objects are obtained in two ways: a hybrid region-merging segmentation method with multispectral images, and a top-down and bottom-up region-growing method with Lidar data. The hybrid region-merging method is used to segment individual tree from multispectral images. It integrates the advantages of global-oriented and local-oriented region-merging strategies into a unified framework. The globally most-similar pair of regions is used to determine the starting point of a growing region. The merging iterations are constrained within the local vicinity, thus the segmentation is accelerated and can reflect the local context. The top-down region-growing method is adopted in coniferous forest to delineate individual tree from Lidar data. It exploits the spacing between the tops of trees to identify and group points into a single tree based on simple rules of proximity and likely tree shape. The bottom-up region-growing method based on the intensity and 3D structure of Lidar data is applied in deciduous forest. It segments tree trunks based on the intensity and topological relationships of the points, and then allocate other points to exact tree crowns according to distance. The accuracies for each method are evaluated with field survey data in several test sites, covering dense and sparse canopy. Three types of segmentation results are produced: true positive represents a correctly segmented individual tree, false negative represents a tree that is not detected and assigned to a nearby tree, and false positive represents that a point or pixel cluster is segmented as a tree that does not in fact exist. They respectively represent correct-, under-, and over-segmentation. Three types of index are compared for segmenting individual tree

  16. New potential phytotherapeutics obtained from white mulberry (Morus alba L.) leaves.

    Science.gov (United States)

    Gryn-Rynko, Anna; Bazylak, Grzegorz; Olszewska-Slonina, Dorota

    2016-12-01

    The present work demonstrates the profound and unique phyto-pharmacological and nutritional profile of white mulberry (Morus alba L.) leaves which containing considerable amounts of easy digestive proteins, carbohydrates, micro- and macronutrients, polyphenols, free amino acids, organic acids. The wide range of significant biopharmaceutical activities of the aqueous and polar organic solvents extracts from mulberry leaves - including antidiabetic, antibacterial, anticancer, cardiovascular, hypolipidemic, antioxidant, antiatherogenic, and anti-inflammatory - have been critically discussed. The main objective was to demonstrate the results of recently published study on the components of white mulberry leaves exhibiting their biological activity in the various pathological and health human ailments. In addition, we intend to drawn the attention of researchers and public health workers for the extended exploration of this deciduous plant leaves as the source of potential indigenous nutraceuticals and functional food products to enable development of alternative prevention and treatment protocols offered in therapy of the common non-communicable diseases and malignances. Copyright © 2016 Elsevier Masson SAS. All rights reserved.

  17. Trends in savanna structure and composition along an aridity gradient in the Kalahari

    CSIR Research Space (South Africa)

    Scholes, RJ

    2002-06-01

    Full Text Available Rooyen 1998). Sa- line areas such as the vast Makgadigadi pan support halophytic shrubs and grasses or are bare. Non-saline pans, for example at Nxai pan, support sedge- and grasslands, sometimes with tree clumps on slightly more elevated ground... being larger than about 20 mm (major axis); fine-leafed is smaller than 20 mm, and usually less than 2 mm. Deciduous means that > 90% of all tree and shrub leaves are lost for at least three months, evergreen means that > 80% of tree leaf is retained...

  18. Environmental studies in two communes of Santiago de Chile by the analysis of magnetic properties of particulate matter deposited on leaves of roadside trees

    Science.gov (United States)

    Muñoz, David; Aguilar, Bertha; Fuentealba, Raúl; Préndez, Margarita

    2017-03-01

    Emissions from motor vehicles are considered to be one of the main sources of airborne particulate matter in Santiago. International researchers have shown that particulate matter contains metal oxides and magnetic particles, both of which are emitted mainly from vehicles exhaust pipes. On the other hand, trees are effective in reducing such contamination, so that they act as passive collectors of particulate matter. This work presents the results obtained from the first magnetic study of the particulate matter collected in two areas of the city of Santiago de Chile. Magnetic susceptibility and Saturation Isothermic Remanent Magnetization (SIRM) were determined in leaves from abundant urban trees and from urban dust samples. Results indicate that most of the samples contain ferromagnetic minerals with magnetite (Fe3O4) as the main carrier. Values of magnetic susceptibility (SI ×10-6 m3/kg) in the range 0.04-0.24 for leaves and in the range 10-45 for urban dust were determinated. In one of the city areas studied, significant correlation between the particulate matter deposited on leaves of Platanus orientalis and measured traffic flows was obtained. In addition, it was possible to estimate that the species Platanus orientalis and Acer negundo have a better ability to capture particulate matter than the species Robinia pseudoacacia.

  19. Behavior of cesium-134 in the tea tree

    International Nuclear Information System (INIS)

    Xu Yinliang; Chen Kaixuan; Chen Chuangqun

    1996-01-01

    The radioactivity changes of 134 Cs in the aged and the young leaves followed an exponential regression function after spraying 134 Cs in the tea trees. Contamination by spraying 134 Cs greatly harmed tea tree and by irrigating or mixing 134 Cs with soil resulted in a potential endangerment. The concentrating ability of tea leaves for 134 CS was very low and K value was 0.02. After the fresh tea leaves were processed to dry tea, the content of 134 Cs decreased by about 13.3%. When the tea leaves were soaked in hot water, the extraction ratio was around 83.6%

  20. Microhabitat of small mammals at ground and understorey levels in a deciduous, southern Atlantic forest.

    Science.gov (United States)

    Melo, Geruza L; Miotto, Barbara; Peres, Brisa; Cáceres, Nilton C

    2013-01-01

    Each animal species selects specific microhabitats for protection, foraging, or micro-climate. To understand the distribution patterns of small mammals on the ground and in the understorey, we investigated the use of microhabitats by small mammals in a deciduous forest of southern Brazil. Ten trap stations with seven capture points were used to sample the following microhabitats: liana, fallen log, ground litter, terrestrial ferns, simple-trunk tree, forked tree, and Piper sp. shrubs. Seven field phases were conducted, each for eight consecutive days, from September 2006 through January 2008. Four species of rodents (Akodon montensis, Sooretamys angouya, Oligoryzomys nigripes and Mus musculus) and two species of marsupials (Didelphis albiventris and Gracilinanus microtarsus) were captured. Captured species presented significant differences on their microhabitat use (ANOVA, p = 0.003), particularly between ground and understorey sites. Akodon montensis selected positively terrestrial ferns and trunks, S. angouya selected lianas, D. albiventris selected fallen trunks and Piper sp., and G. microtarsus choose tree trunks and lianas. We demonstrated that the local small-mammal assemblage does select microhabitats, with different types of associations between species and habitats. Besides, there is a strong evidence of habitat selection in order to diminish predation.

  1. Fulltext PDF

    Indian Academy of Sciences (India)

    Feronia limonia (L.) S~villg/e (B. Koet Bel) (English: Elephant- or Wood-apple; Hindi: Kaithbel, Kaitha,. Kavitha) of Rutaceae is a medium-sized deciduous tree with thorny branches and compound leaves. Flowers are small and white. Fruits are large, globose, of the size of tennis balls with a hard and woody shell enclosing ...

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

    Science.gov (United States)

    Brienen, Roel J W; Zuidema, Pieter A

    2005-11-01

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

  3. Impact of African weaver ant nests [Oecophylla longinoda Latreille (Hymenoptera: Formicidae)] on Mango [Mangifera indica L. (Sapindales: Anacardiaceae)] leaves

    DEFF Research Database (Denmark)

    Anato, Florence; Sinzogan, Antonio; Adandonon, Appolinaire

    2015-01-01

    Oecophylla ants are appreciated for their control of pests in plantation crops. However, the ants´ nest building may have negative impacts on trees. In this study we tested the effect of ant densities and nest building on the leaf performance of mango trees. Trees were divided into three groups......: trees without ants, trees with low and trees with high ant densities. Subsequently, the total number of leaves, the proportion of leaves used for nest construction, and tree growth was compared between these groups. The percentage of leaves used for nests was between 0.42-1.2 % (mean = 0...

  4. An aid in choosing the right tree to leave

    Science.gov (United States)

    C. Allen Bickford

    1953-01-01

    The successful forest manager has a number of well-stocked stands containing trees that are sound, useful, and fast-growing. Each stand and each tree is increasing in value fast enough that its rate of earning equals or exceeds the earnings from comparable investments.

  5. Acidity of tree bark as a bioindicator of forest pollution in southern Poland

    Energy Technology Data Exchange (ETDEWEB)

    Grodzinska, K

    1977-05-01

    pH values and buffering capacity were determined for bark samples of five deciduous trees (oak, alder, hornbeam, ash, linden), one shrub (hazel) and one coniferous tree (scots pine) in the Cracow Industrial Region (southern Poland) and, for comparison, in the Bialowieza Forest (northeastern Poland). The correlation was found between acidification of tree bark and air pollution by SO/sub 2/ in these areas. All trees showed the least acidic reaction in the control area (Bialowieza Forest), more acidic in Niepolomice Forest and the most acidic in the center of Cracow. The buffering capacity of the bark against alkali increased with increasing air pollution. The seasonal fluctuations of pH values and buffering capacity were found. Tree bark is recommended as a sensitive and simple indicator of air pollution.

  6. First report of Apple necrotic mosaic virus infecting apple trees in Korea

    Science.gov (United States)

    In September 2016, two apple trees (Malus domestica Borkh) cv. Shinano Sweet showing bright cream spot and mosaic patterns on leaves were observed in Pocheon, South Korea. Mosaic symptoms are common on leaves of apple trees infected with Apple mosaic virus (ApMV). Symptomatic leaves were tested by e...

  7. Urban Crowns: crown analysis software to assist in quantifying urban tree benefits

    Science.gov (United States)

    Matthew F. Winn; Sang-Mook Lee Bradley; Philip A. Araman

    2010-01-01

    UrbanCrowns is a Microsoft® Windows®-based computer program developed by the U.S. Forest Service Southern Research Station. The software assists urban forestry professionals, arborists, and community volunteers in assessing and monitoring the crown characteristics of urban trees (both deciduous and coniferous) using a single side-view digital photograph. Program output...

  8. How competitive is drought deciduousness in tropical forests? A combined eco-hydrological and eco-evolutionary approach

    Science.gov (United States)

    Vico, Giulia; Dralle, David; Feng, Xue; Thompson, Sally; Manzoni, Stefano

    2017-06-01

    Drought-deciduous and evergreen species are both common in tropical forests, where there is the need to cope with water shortages during periodic dry spells and over the course of the dry season. Which phenological strategy is favored depends on the long-term balance of carbon costs and gains that leaf phenology imposes as a result of the alternation of wet and dry seasons and the unpredictability of rainfall events. This study integrates a stochastic eco-hydrological framework with key plant economy traits to derive the long-term average annual net carbon gain of trees exhibiting different phenological strategies in tropical forests. The average net carbon gain is used as a measure of fitness to assess which phenological strategies are more productive and more evolutionarily stable (i.e. not prone to invasion by species with a different strategy). The evergreen strategy results in a higher net carbon gain and more evolutionarily stable communities with increasing wet season lengths. Reductions in the length of the wet season or the total rainfall, as predicted under climate change scenarios, should promote a shift towards more drought-deciduous communities, with ensuing implications for ecosystem functioning.

  9. Creating 13C- and 15N-enriched tree leaf litter for decomposition experiments

    Science.gov (United States)

    Szlavecz, K. A.; Pitz, S.; Chang, C.; Bernard, M.

    2013-12-01

    Labeling plant material with heavy isotopes of carbon and nitrogen can produce a traceable nutrient signal that can be followed into the different trophic levels and decomposer food web. We treated 60 tree saplings with 13C-enriched CO2 gas and 15N-enriched ammonium nitrate over a three-month period to create dually-labeled plant material for future decomposition experiments. The trees included both early (Red maple, Sweetgum, Tulip poplar) and late (American beech, White oak) successional deciduous tree species, and a conifer, White pine. We constructed a 2.4 m × 2.4 m × 2.4 m environmental chamber that was climate-controlled using an air conditioning system. An Arduino microcontroller interfaced with a Vaisala GMP343 CO2 probe maintained a CO2 concentration between 500-520 ppm by controlling a solenoid valve on the CO2 tank regulator. The trees were placed into the chamber in August 2012 and remained until senescence unless they were lost to death or disease. Ammonium nitrate was added twice, in September and October. Leaf samples were collected prior to the start of the experiment and after senescence, whereas root samples were collected only in December. Samples were dried, ground and analyzed using an isotope ratio mass spectrometer. American beech and White oak had 40% mortality, and 34% of tulip poplar trees were removed because of powdery mildew overgrowth or death. Most tulip poplar trees exhibited a second leaf out following senescence in late September. Nearly 1 kg of litter was produced with tulip poplar representing over half of the total mass. Levels of enrichment varied greatly by species. Beech (-14.2‰) and White oak (-4.8‰) had low levels of enrichment in comparison to early successional species such as Sweetgum (41.7‰) and Tulip poplar (30.7‰ [first leaf fall] and 238.0‰ [second leaf fall]). Leaf enrichment with 15N followed a similar pattern, though it was achieved at a higher level with δ15N values varying from 271.6‰ to 1354.2

  10. Contrasting ozone sensitivity in related evergreen and deciduous shrubs

    Energy Technology Data Exchange (ETDEWEB)

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

    2010-12-15

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

  11. Acidity of tree bark as a bioindicator of forest pollution in southern Poland

    Energy Technology Data Exchange (ETDEWEB)

    Grodznska, K

    1976-01-01

    PH values and buffering capacity were determined for bark samples of 5 deciduous trees (oak, alder, hornbeam, ash, linden), one shrub (hazel) and one coniferous tree (scots pine) in the Cracow industrial region (southern Poland) and for comparison in the Bialowieza Forest (north-eastern Poland). The correlation was found between acidification of tree bark and air pollution by SO/sub 2/ in these areas. All trees showed the least acidic reaction in the control area (Bialowieza Forest), more acidic in Niepolomice Forest and the most acidic in the center of Cracow city. The buffering capacity of the bark against alkali increased with increasing air pollution. The seasonal fluctuations of pH values is recommended as a sensitive and simple indicator of air pollution.

  12. Res Cover Sep 07

    Indian Academy of Sciences (India)

    THOLASI

    Acacia polycantha Willd. (White cutch) of Fabaceae is a moderate sized deciduous tree with white or ash colored bark that peels off in papery flakes. Leaves are compound with many leaflets, spines on either side of the leaf base and a gland on the petiole. Flowers are small, white or pale yellow and are densely arranged ...

  13. Fulltext PDF

    Indian Academy of Sciences (India)

    Srimath

    quick-growing deciduous tree with a small crown. Branches are covered with dark conical prickles, which fall off after some time. The leaves are compound with three leaflets. Bright red or scarlet flowers which appear following leaf fall are in clusters at branch ends. Birds and bees visit flowers for nectar. Fruit is a cylindrical ...

  14. Fulltext PDF

    Indian Academy of Sciences (India)

    Sterculia foetida L. (INDIAN ALMOND,. JAVA OLIVE) of Sterculiaceae is a tall deciduous tree reaching a height of 20 m with faintly ridged grey bark. The bole reaches up to 2m in girth. Branches are reddish, usually horizontal. Leaves are large, palmately compound (5–7 leaflets) and clustered at the branch ends. Flowers ...

  15. [Observation of osteoclasts on the root surface during human deciduous teeth resorption].

    Science.gov (United States)

    Bao, Xiang-jun; Liang, Xing; Chen, Ming; Wang, Hang; Xie, Zhi-gang; Yang, Xiao-yu

    2004-08-01

    To observe osteoclasts on the resorbing surface of human deciduous teeth. After fixing the collected deciduous teeth, we prepared the tooth slices without decalcification, treated them with HE and TRAP dyestuff, and observed the osteoclasts under light and scanning electron microscope. There were large quantity of various forms of overlapping and huge osteoclasts with many nuclei and silk-like protuberances on the resorbing surface of deciduous teeth. The multinucleated osteoclasts align on the surface of coarse dentin. On the resorbing surface of human deciduous teeth there are large amount of osteoclasts which can be used as a source of studying human osteoclast.

  16. Coded Splitting Tree Protocols

    DEFF Research Database (Denmark)

    Sørensen, Jesper Hemming; Stefanovic, Cedomir; Popovski, Petar

    2013-01-01

    This paper presents a novel approach to multiple access control called coded splitting tree protocol. The approach builds on the known tree splitting protocols, code structure and successive interference cancellation (SIC). Several instances of the tree splitting protocol are initiated, each...... instance is terminated prematurely and subsequently iterated. The combined set of leaves from all the tree instances can then be viewed as a graph code, which is decodable using belief propagation. The main design problem is determining the order of splitting, which enables successful decoding as early...

  17. Turning palm leaves into wood: Opportunities for Egypt's rural ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    2016-04-27

    Apr 27, 2016 ... Bedouin women weave handmade baskets, hats, and lamps using dried palm leaves. ... palm tree leaves into hardwood and high-quality wooden products, ... of wood and open doors to job opportunities for rural communities.

  18. Quantitative analysis of arbutin and hydroquinone in strawberry tree (Arbutus unedo L., Ericaceae) leaves by gas chromatography-mass spectrometry.

    Science.gov (United States)

    Jurica, Karlo; Karačonji, Irena Brčić; Šegan, Sandra; Opsenica, Dušanka Milojković; Kremer, Dario

    2015-09-01

    The phenolic glycoside arbutin and its metabolite with uroantiseptic activity hydroquinone occur naturally in the leaves of various medicinal plants and spices. In this study, an extraction procedure coupled with gas chromatography-mass spectrometry (GC-MS) was developed to determine arbutin and hydroquinone content in strawberry tree (Arbutus unedo L., Ericaceae) leaves. The method showed good linearity (R2>0.9987) in the tested concentration range (0.5-200 μg mL(-1)), as well as good precision (RSD<5%), analytical recovery (96.2-98.0%), and sensitivity (limit of detection=0.009 and 0.004 μg mL(-1) for arbutin and hydroquinone, respectively). The results obtained by the validated GC-MS method corresponded well to those obtained by high performance liquid chromatography (HPLC) method. The proposed method was then applied for determining arbutin and hydroquinone content in methanolic leaf extracts. The amount of arbutin in the leaves collected on the island of Koločep (6.82 mg g(-1) dry weight) was found to be higher (tpaired=43.57, tc=2.92) in comparison to the amount of arbutin in the leaves collected on the island of Mali Lošinj (2.75 mg g(-1) dry weight). Hydroquinone was not detected in any of the samples. The analytical features of the proposed GC-MS method demonstrated that arbutin and hydroquinone could be determined alternatively by gas chromatography. Due to its wide concentration range, the method could also be suitable for arbutin and hydroquinone analysis in leaves of other plant families (Rosaceae, Lamiaceae, etc.).

  19. Folate Deficiency Could Restrain Decidual Angiogenesis in Pregnant Mice

    Directory of Open Access Journals (Sweden)

    Yanli Li

    2015-08-01

    Full Text Available The mechanism of birth defects induced by folate deficiency was focused on mainly in fetal development. Little is known about the effect of folate deficiency on the maternal uterus, especially on decidual angiogenesis after implantation which establishes vessel networks to support embryo development. The aim of this study was to investigate the effects of folate deficiency on decidual angiogenesis. Serum folate levels were measured by electrochemiluminescence. The status of decidual angiogenesis was examined by cluster designation 34 (CD34 immunohistochemistry and the expression of angiogenic factors, including vascular endothelial growth factor A (VEGFA, placental growth factor (PLGF, and VEGF receptor 2 (VEGFR2 were also tested. Serum levels of homocysteine (Hcy, follicle stimulating hormone (FSH, luteinizing hormone (LH, prolactin (PRL, progesterone (P4, and estradiol (E2 were detected by Enzyme-linked immunosorbent assay. The folate-deficient mice had a lower folate level and a higher Hcy level. Folate deficiency restrained decidual angiogenesis with significant abnormalities in vascular density and the enlargement and elongation of the vascular sinus. It also showed a reduction in the expressions of VEGFA, VEGFR2, and PLGF. In addition, the serum levels of P4, E2, LH, and PRL were reduced in folate-deficient mice, and the expression of progesterone receptor (PR and estrogen receptor α (ERα were abnormal. These results indicated that folate deficiency could impaire decidual angiogenesis and it may be related to the vasculotoxic properties of Hcy and the imbalance of the reproductive hormone.

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

    NARCIS (Netherlands)

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

    2009-01-01

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

  1. Suficiência amostral para coletas de serapilheira acumulada sobre o solo em Pinus elliottii Engelm, Eucalyptus sp. E floresta estacional decidual Adequate sampling for collection of litter accumulated on the soil in Pinus elliottii engelm, Eucalyptus sp. And seasonal deciduous forest

    Directory of Open Access Journals (Sweden)

    Isabel Sandra Kleinpaul

    2005-12-01

    leaves, branches, reproductive structures, barks and wastes. Based on the dry weights of each fraction, a statistical analysis was carried out, aiming the stabilization of the coefficient of variation (CV%. For Pinus elliotti, "needles" was the fraction that contributed the most, 57.2%; for the Eucalyptus sp., the branches contributed with 38.8%; and for the Seasonal Deciduous Forest the leaves contributed with 46.9%. The highest CV% in Pinus elliottii was for the wastes, followed by the reproductive structures. In Eucalyptus sp. the highest CV% was for barks, followed by branches. In the Seasonal Deciduous Forest, the barks had the highest CV%. The sample sufficiency for Pinus elliotti was 40, so this stand needed fewer samples to stabilize the CV%. For Eucalyptus sp. the sample sufficiency was 70, and in the Seasonal Deciduous Forest 80 samples were needed.

  2. 137Cs dynamics in the forest of Fukushima after the nuclear power plant accident in March 2011

    Science.gov (United States)

    Endo, I.; Ohte, N.; Iseda, K.; Kobayashi, N.; Hirose, A.; Tanoi, K.

    2013-12-01

    The accident of Fukushima Daiichi nuclear power plant after the earthquake and Tsunami in March 11th 2011, caused large amount of radioactive Cesium (137Cs) emission into the environment. In the region of Fukushima Prefecture, forest dominates more than 70 % of the land area. River water from the forest area is used for food production and also for drinking water. Thus, it is important to understand the dynamics of 137Cs deposited in the forest to predict how the radioactive Cs diffuse and discharge from the forest catchments. We measured 137Cs concentration of the tree body, litter fall, throughfall, and stemflow, in order to clarify how 137Cs deposited on the above ground biomass of the forest are transported to the forest floor. We set forest site at the upstream part of Kami-Oguni River catchment, northern part of Fukushima Prefecture. Three plots (2 deciduous stands and 1 Japanese cedar (Cryptomeria japonica) plantation stand) were set in the forest site. Quercus serrata and C. japonica, which are representative tree species, were chosen at each plot and concentration of 137Cs on the bark, sapwood and heartwood were measured every 2 m from the ground to tree top. From each plot, 137Cs concentration of leaf litter was measured among species. Water samples of throughfall and stemflow were filtered and 137Cs concentration in suspended matter was measured. 137Cs was deposited on the bark of Q. serrata at high concentration (9-18 kBq/kg) but there were no clear relationship between tree height and concentration. 137Cs concentration of the sapwood (41 Bq/kg) was relatively higher than that of the heartwood (5 Bq/kg). It was suggested that 137Cs may be absorbed from bark and/or root. The concentration of 137Cs deposited in leaf litter varied from non-detected level to above 30 kBq/kg. The concentration was higher at evergreen tree than deciduous tree. It is considered that the litter of evergreen tree was derived from leaves on the tree canopy at the time of the

  3. Reconstruction of certain phylogenetic networks from their tree-average distances.

    Science.gov (United States)

    Willson, Stephen J

    2013-10-01

    Trees are commonly utilized to describe the evolutionary history of a collection of biological species, in which case the trees are called phylogenetic trees. Often these are reconstructed from data by making use of distances between extant species corresponding to the leaves of the tree. Because of increased recognition of the possibility of hybridization events, more attention is being given to the use of phylogenetic networks that are not necessarily trees. This paper describes the reconstruction of certain such networks from the tree-average distances between the leaves. For a certain class of phylogenetic networks, a polynomial-time method is presented to reconstruct the network from the tree-average distances. The method is proved to work if there is a single reticulation cycle.

  4. Do you believe in palm trees?

    Science.gov (United States)

    Kevin T. Smith

    2013-01-01

    Palms are real, but are they really trees? The answer depends on definitions. As usually tall, peremrial plants with roots, stems, and leaves, palms seem to qualify. Palms should also qualify because arborists care for them, and arborists care for trees, right? My introduction to botany class defined trees as plants that produce wood. Unraveling the question of whether...

  5. Seasonal variability of interception and water wettability of common oak leaves

    Directory of Open Access Journals (Sweden)

    Anna Klamerus-Iwan

    2017-07-01

    Full Text Available Wettability of leaves and the resulting amount of interception loss of tree crowns is an important component of the atmosphere-tree stand-soil system balance. In the study, we hypothesized that changes occurring in leaves during the vegetation period can significantly affect the amount of rainwater retained by plants and wettability of leaves which is expressed by the contact angle between drops and leaves. We evaluated the hypothesis based on measurement series, which combined direct spraying of leaves with water at different stages of development at a constant temperature with observations made with an electron scanner which was used to determine changes occurring within a leaf, while the photographic method was used to analyze the contact angle of drops. The study involved common oak (Quercus robur. Samples of twigs derived from this species were collected in the area of Przedbórz (Poland forest district, in particular from the trees with well-developed crowns. Twigs were collected from 10 trees of similar age (35–40 years. The resulting database contained experimental data on changes of raindrop adhesion on oak leaves throughout the growing season. The internal contact angle of drops was within the range of 150° on the upper side of the leaf and 160° on the underside in May, up to 15° and 35° in November on the upper and underside of the leaves. Loss of interception was established at 6% at the beginning of the growing season up to 22% in autumn. It was concluded that the wettability and the level of interception increases in line with the age of a leaf.

  6. Physiological, morphological and allocational plasticity in understory deciduous trees: importance of plant size and light availability.

    Science.gov (United States)

    Delagrange, Sylvain; Messier, Christian; Lechowicz, Martin J; Dizengremel, Pierre

    2004-07-01

    In a 4-year study, we investigated changes in leaf physiology, crown morphology and whole-tree biomass allocation in seedlings and saplings of shade-tolerant sugar maple (Acer saccharum Marsh.) and intermediate shade-tolerant yellow birch (Betula alleghaniensis Britt.) growing in natural understory light (0.5 to 35% of full sunlight) or in understory light reduced by 50% with shade nets to simulate the effect of gap closure. Leaf physiological parameters were mainly influenced by the light gradient, whereas crown morphological and whole-tree allocational parameters were mainly influenced by tree size. No single physiological, morphological or allocational trait was identified that could explain the difference in shade tolerance between the species. Yellow birch had higher growth rates, biomass allocation to branches and leaf physiological plasticity and lower crown morphological plasticity in unmodified understory light than sugar maple. Sugar maple did not display significant physiological plasticity, but showed variation with tree size in both crown morphology and whole-tree biomass allocation. When sugar maple was small, a greater proportion of whole-tree biomass was allocated to roots. However, physiological differences between the species decreased with decreasing light and most morphological and allocational differences tended to disappear with increasing tree size, suggesting that many species differences in shade-tolerance are expressed mainly during the seedling stage. Understory trees of both species survived for 4 years under shade nets, possibly because of higher plasticity when small and the use of stored reserves when taller. Copyright 2004 Heron Publishing

  7. Tree damage from skyline logging in a western larch/Douglas-fir stand

    Science.gov (United States)

    Robert E. Benson; Michael J. Gonsior

    1981-01-01

    Damage to shelterwood leave trees and to understory trees in shelterwood and clearcut logging units logged with skyline yarders was measured, and related to stand conditions, harvesting specifications, and yarding system-terrain interactions. About 23 percent of the marked leave trees in the shelterwood units were killed in logging, and about 10 percent had moderate to...

  8. Gall-inducing insects of deciduous and semideciduous forests in Rio Grande do Sul State, Brazil

    Directory of Open Access Journals (Sweden)

    Ana Paula M. Goetz

    2018-06-01

    Full Text Available ABSTRACT Galls are specific changes induced by insects on plant organs mainly through increases in plant cell number and/or size. Gall diversity is easy to recognize in the field because gallers are mostly species-specific, and thus each gall morphotype can be a proxy for a galling species. Insect galls are virtually unknown in Seasonal Deciduous and Semi-Deciduous forests of southern Brazil. Here, galls and host plants were surveyed between 2015 and 2017 in four forest fragments of Rio Grande do Sul State in these two vegetation types, in secondary-growth and areas under restoration. We recorded 89 gall morphotypes, with gallers belonging to Lepidoptera and Diptera, with the latter represented mainly by Cecidomyiidae. Galls were associated to 46 plant species in 27 families. Asteraceae, Piperaceae, Fabaceae, Myrtaceae and Lauraceae were the richest families in terms of galls, whilst Piper aduncum and Mikania glomerata were superhosts. Most galls occurred in leaves and shoots. The most common shapes were fusiform, globoid and lenticular. Forty-eight gall morphotype records are new for both Rio Grande do Sul and Brazil, an expressive number considering only two seasonal forest types sampled and few sampling points, showing how important surveys still are for these little know fauna both in taxonomic and ecological terms.

  9. Oxygen and Hydrogen Stable Isotope Composition of Eocene ( ~45 million year old) Fossil Tree Cellulose

    Science.gov (United States)

    Jahren, H.

    2001-05-01

    I report on \\delta18O and \\deltaD values gained from unusually old tree fossils, collected on Axel Heiberg Island of the Canadian High Arctic. A variety of workers have measured the δ ^{18}O value of cellulose and the δ D value of cellulose nitrate isolated from modern trees and compared it to various environmental parameters (esp. Epstein et al., 1977: 14 tree species sampled at 16 sites ranging from 18 \\deg to 62 \\deg North latitude; \\delta18O of cellulose ranged from +20 to +33 \\permil; \\deltaD of cellulose nitrate ranged from -181 to +18). To date the paleoenvironmental interpretations resulting from these studies have been restricted to application in recent and Quaternary earth history due to the lack of sufficiently preserved cellulose and tree ring structure in older tree fossils. An exception to this generalization are the middle Eocene (\\sim45 my old) fossil forests of Axel Heiberg Island, which contain abundant stumps, branches, twigs, cones and leaves of Metasequoia trees in exquisite preservational condition. These deciduous trees grew at a paleolatitude of 80 ° North, and endured prolonged periods of continuous daylight in the summer and continuous darkness in the winter, making the ecosystem completely unlike any forest community existing today. Fossil wood samples from the site have been slightly compressed, but otherwise exhibit minimal alteration: %C and % cellulose (by mass) are similar to modern Metasequoia wood. δ ^{18}O analyses on cellulose isolated from 14 fossil individuals has yielded the following results: range = +17 to +20 ‰ ; mean = +19 ‰ ; variability within an individual = 0.5 to 1.0 ‰ . In presentation, I will complement these results with δ D determinations on cellulose nitrate isolated from the same individuals, as well as from small plants presently growing in the arctic. I will also discuss the surprising result that Axel Heiberg fossil trees appear to have stable isotope composition as low or lower than trees

  10. Unravelling spatiotemporal tree-ring signals in Mediterranean oaks: a variance-covariance modelling approach of carbon and oxygen isotope ratios.

    Science.gov (United States)

    Shestakova, Tatiana A; Aguilera, Mònica; Ferrio, Juan Pedro; Gutiérrez, Emilia; Voltas, Jordi

    2014-08-01

    Identifying how physiological responses are structured across environmental gradients is critical to understanding in what manner ecological factors determine tree performance. Here, we investigated the spatiotemporal patterns of signal strength of carbon isotope discrimination (Δ(13)C) and oxygen isotope composition (δ(18)O) for three deciduous oaks (Quercus faginea (Lam.), Q. humilis Mill. and Q. petraea (Matt.) Liebl.) and one evergreen oak (Q. ilex L.) co-occurring in Mediterranean forests along an aridity gradient. We hypothesized that contrasting strategies in response to drought would lead to differential climate sensitivities between functional groups. Such differential sensitivities could result in a contrasting imprint on stable isotopes, depending on whether the spatial or temporal organization of tree-ring signals was analysed. To test these hypotheses, we proposed a mixed modelling framework to group isotopic records into potentially homogeneous subsets according to taxonomic or geographical criteria. To this end, carbon and oxygen isotopes were modelled through different variance-covariance structures for the variability among years (at the temporal level) or sites (at the spatial level). Signal-strength parameters were estimated from the outcome of selected models. We found striking differences between deciduous and evergreen oaks in the organization of their temporal and spatial signals. Therefore, the relationships with climate were examined independently for each functional group. While Q. ilex exhibited a large spatial dependence of isotopic signals on the temperature regime, deciduous oaks showed a greater dependence on precipitation, confirming their higher susceptibility to drought. Such contrasting responses to drought among oak types were also observed at the temporal level (interannual variability), with stronger associations with growing-season water availability in deciduous oaks. Thus, our results indicate that Mediterranean deciduous

  11. [Spectral navigation technology and its application in positioning the fruits of fruit trees].

    Science.gov (United States)

    Yu, Xiao-Lei; Zhao, Zhi-Min

    2010-03-01

    An innovative technology of spectral navigation is presented in the present paper. This new method adopts reflectance spectra of fruits, leaves and branches as one of the key navigation parameters and positions the fruits of fruit trees relying on the diversity of spectral characteristics. The research results show that the distinct smoothness as effect is available in the spectrum of leaves of fruit trees. On the other hand, gradual increasing as the trend is an important feature in the spectrum of branches of fruit trees while the spectrum of fruit fluctuates. In addition, the peak diversity of reflectance rate between fruits and leaves of fruit trees is reached at 850 nm of wavelength. So the limit value can be designed at this wavelength in order to distinguish fruits and leaves. The method introduced here can not only quickly distinguish fruits, leaves and branches, but also avoid the effects of surroundings. Compared with the traditional navigation systems based on machine vision, there are still some special and unique features in the field of positioning the fruits of fruit trees using spectral navigation technology.

  12. 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.

  13. The accumulation and elimination of 89Sr in tea leaves

    International Nuclear Information System (INIS)

    Zhang Yongxi; Wang Shouxiang; Chen Chuanqun; Sun Zhiming; Hu Bingmin; Huang Dan

    1995-01-01

    The 89 Sr was added to the tea tree-soil system by different ways. The 89 Sr in the system through the over-ground part of tea tree, was much more than that through soil. The 89 Sr concentration in older leaves was higher than in shoot for a definite treatment. The accumulation elimination law of 89 Sr in leaves varied with the treatments. For the treatment through the over-ground part, the 89 Sr concentration in older leaves and shoot was monotonously decreased with time increasing. But for the treatment through soil the 89 Sr concentration in shoot was increased to reach a peak value, and then decreased slowly; while the 89 Sr concentration in older leaves increased quickly in a period, then increased slowly to attain a saturated value. In addition, the concentration factor of 89 Sr in older leaves and shoot were determined

  14. Decidual activin: its role in the apoptotic process and its regulation by prolactin.

    Science.gov (United States)

    Tessier, Christian; Prigent-Tessier, Anne; Bao, Lei; Telleria, Carlos M; Ferguson-Gottschall, Susan; Gibori, Gil B; Gu, Yan; Bowen-Shauver, Jennifer M; Horseman, Nelson D; Gibori, Geula

    2003-05-01

    Successful pregnancy requires profound differentiation and reorganization of the uterine tissues including, as pregnancy progresses, extensive apoptosis of decidual tissue to accommodate the developing conceptus. We have previously shown a positive correlation between expression of activin A and apoptosis in the decidua and have also shown that expression of activin A occurs at the time when prolactin (PRL) receptors disappear from decidual cells. The goals of this study were to examine whether activin A plays a role in decidual apoptosis and whether expression of activin A in the decidua is regulated by PRL and placental lactogens. Studies were carried out using primary rat decidual cells, a decidual cell line (GG-AD), and PRL null mice. Treatment of decidual cells with activin A significantly increased DNA degradation, caspase 3 activity, and caspase 3 mRNA expression. However, this effect was observed only in the absence of endogenous activin production by these cells. Addition of follistatin to decidual cells that were producing activin A decreased both caspase 3 activity and mRNA expression. Similarly, addition of activin-blocking antibodies to cultures of GG-AD cells, which also produce activin A, caused a reduction in both DNA degradation and caspase 3 activity. PRL and placental lactogens caused an inhibition of activin A mRNA expression in primary decidual cells. Even more convincingly, decidua of PRL null mice expressed abundant activin A at a time when no expression of this hormone is detected in wild-type mice and treatment of PRL null mice with PRL caused a profound inhibition of activin A mRNA expression. In summary, our investigations into the role and regulation of decidual activin have revealed that activin A can induce cell death in the decidua and that its expression is under tight regulation by PRL and placental lactogens.

  15. Red reveals branch die-back in Norway maple Acer platanoides.

    Science.gov (United States)

    Sinkkonen, Aki

    2008-09-01

    Physiological data suggest that autumn leaf colours of deciduous trees are adaptations to environmental stress. Recently, the evolution of autumn colouration has been linked to tree condition and defence. Most current hypotheses presume that autumn colours vary between tree individuals. This study was designed to test if within-tree variation should be taken into account in experimental and theoretical research on autumn colouration. Distribution of red autumn leaf colours was compared between partially dead and vigorous specimens of Norway maple (Acer platanoides) in a 3-year study. In August, the amount of reddish foliage was estimated in pairs of partially dead and control trees. Within-tree variation in the distribution of reddish leaves was evaluated. Leaf nitrogen and carbon concentrations were analysed. Reddish leaf colours were more frequent in partially dead trees than in control trees. Reddish leaves were evenly distributed in control trees, while patchiness of red leaf pigments was pronounced in partially dead trees. Large patches of red leaves were found beneath or next to dead tree parts. These patches reoccurred every year. Leaf nitrogen concentration was lower in reddish than in green leaves but the phenomenon seemed similar in both partially dead and control trees. The results suggest that red leaf colouration and branch condition are interrelated in Norway maple. Early reddish colours may be used as an indication of leaf nitrogen and carbon levels but not as an indication of tree condition. Studies that concentrate on entire trees may not operate at an optimal level to detect the evolutionary mechanisms behind autumnal leaf colour variation.

  16. Determination of feed value of cherry, apricot and almond tree ...

    African Journals Online (AJOL)

    Therefore, almond tree leaves could be used with forage in ruminant diets to reduce cost of animals feed requirements. Overall, it seemed that the tree leaves used in this study, had a higher nutritive value in ruminant's nutrition, however more experiments are needed for an accurate determination of nutritional values of ...

  17. Higher plants as biomonitors of radionuclides in urban air

    International Nuclear Information System (INIS)

    Ajtic, J.; Todorovic, D.; Popovic, D.; Nikolic, J.

    2011-01-01

    Two deciduous tree genera, linden (Tilia tomentosa L. and Tilia cordata Mill.) and chestnut (Aesculus hippocastanum L.), are analysed as biomonitors of 210 Pb and 7 Be in air. In a multi year study (2002 - 2009), conducted in three city parks in Belgrade, the content of 210 Pb and 7 Be in samples of leaves of linden and chestnut trees, and aerosols was determined on an HPGe detector by standard gamma spectrometry. The differences seen in the radionuclides' activities across the measurement sites and between the tree genera are not significant, suggesting that the micro climate, level of air pollution and physiological characteristics of the trees have a negligible effect on the radionuclides' activities in leaves. Linear Pearson's correlation coefficients are used to correlate the 210 Pb and 7 Be activities in aerosols and in leaves. The results show that linden could be used as a 210 Pb biomonitor which provides information on the recent history of exposure. No large positive correlation is found for the 7 Be activities in leaves and aerosols, indicating that higher plants are not a suitable biomonitor for this radionuclide. [sr

  18. Estimation of Heavy Metals in Neem Tree Leaves along Katsina ...

    African Journals Online (AJOL)

    Michael Horsfall

    Key Words: Neem tree, Heavy metals, Pollution. Determination ... concentrations of pollutants in the tree bark correlate with those of ... hence are not readily detoxified and removed by .... levels can severely damage the brain and kidneys and.

  19. Flowering T Flowering Trees

    Indian Academy of Sciences (India)

    Adansonia digitata L. ( The Baobab Tree) of Bombacaceae is a tree with swollen trunk that attains a dia. of 10m. Leaves are digitately compound with leaflets up to 18cm. long. Flowers are large, solitary, waxy white, and open at dusk. They open in 30 seconds and are bat pollinated. Stamens are many. Fruit is about 30 cm ...

  20. 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...... on forest floor C and N content was primarily attributed to large differences in turnover rates as indicated by fractional annual loss of forest floor C and N. The C/N ratio of foliar litterfall was a good indicator of forest floor C and N contents, fractional annual loss of forest floor C and N...

  1. Cephalanthus occidentalis L.

    Science.gov (United States)

    K.F Connor

    2004-01-01

    Buttonbush is a deciduous, wetland shrub or small tree that can reach 6 m in height but generally averages 1 to 3 m tall. The trunk base is often swollen. Branches are generally green when young but darken upon maturity and have conspicuous, raised lenticels. The short-petioled glossy green leaves are elliptic or lanceolate-oblong; they are mostly opposite but, on the...

  2. Rhus copallinum L.

    Science.gov (United States)

    K.F Connor

    2004-01-01

    Shining sumac is an upright, deciduous, clonal shrub or (rarely) small tree from 3 to 6 m tall. Bark ranges in color from light brown to gray to reddish-brown. Shoots and twigs are hairy and reddish in color. Twigs have conspicuous lenticels. The sparsely branched, flat crown is composed of alternate, pinnately compound leaves approximately 15 to 30 cm long, with wings...

  3. Useful trees in reforestation planning at the Biosphere Reserve «Buenavista», Cuba

    Directory of Open Access Journals (Sweden)

    Pedro Herrera Oliver

    2015-06-01

    Full Text Available In Cuba, Biosphere Reserves protect and keep natural areas of variable size including one or several forest, scrub or grassland vegetation units, either primary or secondary, also taking into account the various kinds of complex vegetation and communities. The Biosphere Reserve Buenavista, located in Central Cuba, includes several primary vegetation units such as the mangrove forest, sandy coast and rocky coast vegetation, littoral scrub and the dry semi-deciduous, semi-deciduous and gallery forests. Ferns and their allies, gimnosperms and angiosperms were determined and listed in the Reserve and dominant or dominated tree taxa were selected, also listing their standard heights with the ultimate purpose of using them in future reforestation planning if deforestation in some zones occurs.

  4. Seasonal variation in radiocesium concentrations in three tree species

    International Nuclear Information System (INIS)

    Garten, C.R. Jr.; Briese, L.A.; Sharitz, R.R.; Gentry, J.B.

    1975-01-01

    Radiocesium concentrations in leaves and stems of black willow (Salix nigra), wax myrtle (Myrica cerifera), and tag alder (Alnus serrulata) trees inhabiting a floodplain contaminated by production-reactor effluents were measured over 1 year. In willow and myrtle trees, leaf radiocesium levels were highest in the spring and declined during the growing season; stem levels remained relatively unchanged or exhibited a slight increase. Seasonal changes in alder tree parts depended on the site examined. The relationship among component parts was essentially consistent across species and collecting sites in the summer. The radiocesium concentrations in order of rank were: roots greater than or equal to leaves greater than stems. Species differences in component-part radiocesium levels were dependent on the part sampled and the collecting site examined. Mean soil to plant-part concentration factors in summer ranged from 0.9 to 7.6, and species means across leaves, stems, and roots averaged 2.1, 3.8, and 6.2 for alder, willow, and myrtle trees, respectively

  5. Relationship between leaf optical properties, chlorophyll fluorescence and pigment changes in senescing Acer saccharum leaves.

    Science.gov (United States)

    Junker, Laura Verena; Ensminger, Ingo

    2016-06-01

    The ability of plants to sequester carbon is highly variable over the course of the year and reflects seasonal variation in photosynthetic efficiency. This seasonal variation is most prominent during autumn, when leaves of deciduous tree species such as sugar maple (Acer saccharum Marsh.) undergo senescence, which is associated with downregulation of photosynthesis and a change of leaf color. The remote sensing of leaf color by spectral reflectance measurements and digital repeat images is increasingly used to improve models of growing season length and seasonal variation in carbon sequestration. Vegetation indices derived from spectral reflectance measurements and digital repeat images might not adequately reflect photosynthetic efficiency of red-senescing tree species during autumn due to the changes in foliar pigment content associated with autumn phenology. In this study, we aimed to assess how effectively several widely used vegetation indices capture autumn phenology and reflect the changes in physiology and photosynthetic pigments during autumn. Chlorophyll fluorescence and pigment content of green, yellow, orange and red leaves were measured to represent leaf senescence during autumn and used as a reference to validate and compare vegetation indices derived from leaf-level spectral reflectance measurements and color analysis of digital images. Vegetation indices varied in their suitability to track the decrease of photosynthetic efficiency and chlorophyll content despite increasing anthocyanin content. Commonly used spectral reflectance indices such as the normalized difference vegetation index and photochemical reflectance index showed major constraints arising from a limited representation of gradual decreases in chlorophyll content and an influence of high foliar anthocyanin levels. The excess green index and green-red vegetation index were more suitable to assess the process of senescence. Similarly, digital image analysis revealed that vegetation

  6. The use of deciduous molars in EPR dose reconstruction

    International Nuclear Information System (INIS)

    El-faramawy, N.A.; Wieser, A.

    2005-01-01

    The use of deciduous teeth in EPR dose reconstruction has the unique potential to measure individual doses that were accumulated in the early childhood in the age up to 12 years. It was found previously that due to the small size of deciduous incisors, the available amount of enamel is not sufficient for EPR measurements. Therefore, dose assessment with deciduous incisors can only be done by measurement of whole teeth, including enamel and dentine. The measurement of whole teeth instead of enamel alone is possibly less reliable for dose reconstruction because the stability of CO 2 - radicals (that are an indicator for the absorbed dose) in biologically active dentine is not known. In the present study naturally loosed deciduous molars were investigated. The feasibility of separating enamel from small size molars was analysed. EPR spectrum parameters of whole molars and separated enamel only were evaluated before and after laboratory irradiation. The EPR signal amplitudes of the CO 2 - and native signals were determined by spectrum deconvolution, in dependence on radiation dose in the range 0.1 - 10 Gy. The fading at room temperature of native and CO 2 - EPR signals was analysed. The detection threshold for absorbed dose in enamel was determined.

  7. High rates of carbon storage in old deciduous forests: Emerging mechanisms from the Forest Accelerated Succession ExperimenT (FASET)

    Science.gov (United States)

    Gough, C. M.; Nave, L. E.; Hardiman, B. S.; Bohrer, G.; Halperin, A.; Maurer, K.; Le Moine, J.; Nadelhoffer, K.; Vogel, C. S.; Curtis, P.; University Of Michigan Biological Station Forest Ecosystem Study (Umbs-Fest) Team

    2010-12-01

    Deciduous forests of the eastern US are broadly approaching an ecological threshold in which early successional dominant trees are senescing and giving way to later successional species, with unknown consequences for regional carbon (C) cycling. Though recent research demonstrates that forests may accumulate C for centuries, the mechanisms behind sustained rates of C storage in old, particularly deciduous, forests have not been identified. In a regionally representative forest at the University of Michigan Biological Station, we are combining observational and experimental C cycling studies to forecast how forest C storage responds to climate variation, disturbance, and succession. The Forest Accelerated Succession ExperimenT (FASET), in which >6,700 aspen and birch trees (~35 % LAI) were stem girdled within a 39 ha area, is testing the hypothesis that forest production will increase rather than decline with age, due to increases in nitrogen (N) availability, N allocation to the canopy, and the concurrent development of a more biologically and structurally complex canopy. Results thus far support our hypothesis that aging forests in the region may sustain high rates of C storage through shifts in N cycling and increased canopy complexity. Girdling-induced mortality of early successional species reduced soil respiration, accelerated fine root turnover, and prompted the redistribution of N from the foliage of early to later successional species. Nitrogen redistribution increased leaf area index (LAI) production by later successional species, offsetting declines in LAI from senescing early successional species. High rates of net primary production (NPP) were sustained in stands comprising a diverse assemblage of early and later successional species because later successional species, when already present in the canopy, rapidly compensated for declining growth of early successional species. Canopy structural complexity, which increased with forest age, was positively

  8. Are tree ontogenetic structure and allometric relationship independent of vegetation formation type? A case study with Cordia oncocalyx in the Brazilian caatinga

    Science.gov (United States)

    Silveira, Andréa P.; Martins, Fernando R.; Araújo, Francisca S.

    2012-08-01

    In temperate and tropical rainforests, ontogenetic structure and allometry during tree ontogeny are often associated with light gradients. Light is not considered a limiting resource in deciduous thorny woodland (DTW), but establishment and growth occur during a short rainy period, when the canopy is fully leaved and light in the understory may be modified. Our aim was to investigate whether the light gradient in DTW and the biomechanical limitations of tree growth would be enough to produce an ontogenetic structure and allometric growth similar to rainforest canopy trees. We investigated the ontogenetic stages and diameter-height relationship of Cordia oncocalyx (Boraginaceae), a dominant canopy tree of the DTW of semiarid northeastern Brazil. We tagged, measured and classified the ontogenetic stages of 2.895 individuals in a 1 ha area (5°6'58.1″S and 40°52'19.4″W). In the rainy season only 4.7% of the light falling on the canopy reached the ground. Initial ontogenetic stages, mainly infant (50.9%) and seedling (42.1%), were predominant in the population, with the remaining 7% distributed among juvenile, immature, virginile and reproductive. The ontogenetic structure was similar to that of rainforest tree species, but the population formed both permanent seed and infant banks in response to long dry periods and erratic rainy spells. Like many other Boraginaceae tree species in tropical rainforests, C. oncocalyx has a Prévost architectural model, but allometric growth was quite different from rainforest trees. C. oncocalyx invested slightly more in diameter at first, then in height and finally invested greatly in diameter and attained an asymptotic height. The continued high investment in diameter growth at late stages and the asymptotic height point to low tree density and more frequent xylem embolism as the main drivers of tree allometric shape in DTW. This indicates that tree ontogenetic structure and allometric relationships depend on vegetation

  9. 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.

  10. Electron Tree

    DEFF Research Database (Denmark)

    Appelt, Ane L; Rønde, Heidi S

    2013-01-01

    The photo shows a close-up of a Lichtenberg figure – popularly called an “electron tree” – produced in a cylinder of polymethyl methacrylate (PMMA). Electron trees are created by irradiating a suitable insulating material, in this case PMMA, with an intense high energy electron beam. Upon discharge......, during dielectric breakdown in the material, the electrons generate branching chains of fractures on leaving the PMMA, producing the tree pattern seen. To be able to create electron trees with a clinical linear accelerator, one needs to access the primary electron beam used for photon treatments. We...... appropriated a linac that was being decommissioned in our department and dismantled the head to circumvent the target and ion chambers. This is one of 24 electron trees produced before we had to stop the fun and allow the rest of the accelerator to be disassembled....

  11. The symbiotic relationship between dominant canopy trees and soil microbes affects the nitrogen source utilization of co-existing understory trees

    Science.gov (United States)

    Iwaoka, C.; Hyodo, F.; Taniguchi, T.; Shi, W.; Du, S.; Yamanaka, N.; Tateno, R.

    2017-12-01

    The symbiotic relationship between dominant canopy trees and soil microbes such as mycorrhiza or nitrogen (N) fixer are important determinants of soil N dynamics of a forest. However, it is not known how and to what extent the symbiotic relationship of dominant canopy trees with soil microbes affect the N source of co-existing trees in forest. We measured the δ15N of surface soils (0-10 cm), leaves, and roots of the dominant canopy trees and common understory trees in an arbuscular mycorrhizal N-fixing black locust (Robinia pseudoacacia) plantation and an ectomycorrhizal oak (Quercus liaotungensis) natural forest in a China dryland. We also analyzed the soil dissolved N content in soil extracts and absorbed by ion exchange resin, and soil ammonia-oxidizer abundance using real-time PCR. The δ15N of soil and leaves were higher in the black locust forest than in the oak forest, although the δ15N of fine roots was similar in the two forests, in co-existing understory trees as well as dominant canopy trees. Accordingly, the δ15N of leaves was similar to or higher than that of fine roots in the black locust forest, whereas it was consistently lower than that of fine roots in the oak forest. In the black locust forest, the soil dissolved organic N and ammonium N contents were less abundant but the nitrate N contents in soils and absorbed by the ion exchange resin and ammonia-oxidizer abundance were greater, due to N fixation or less uptake of organic N from arbuscular mycorrhiza. In contrast, the soil dissolved organic N and ammonium N contents were more abundant in the oak forest, whereas the N content featured very low nitrate, due to ectomycorrhizal ability to access organic N. These results suggest that the main N source is nitrate N in the black locust forest, but dissolved organic N or ammonium N in the oak forest. N fixation or high N loss due to high N availability would cause high δ15N in soil and leaves in black locust forest. On the other hand, low soil N

  12. Involvement of atypical transcription factor E2F8 in the polyploidization during mouse and human decidualization.

    Science.gov (United States)

    Qi, Qian-Rong; Zhao, Xu-Yu; Zuo, Ru-Juan; Wang, Tong-Song; Gu, Xiao-Wei; Liu, Ji-Long; Yang, Zeng-Ming

    2015-01-01

    Polyploid decidual cells are specifically differentiated cells during mouse uterine decidualization. However, little is known about the regulatory mechanism and physiological significance of polyploidization in pregnancy. Here we report a novel role of E2F8 in the polyploidization of decidual cells in mice. E2F8 is highly expressed in decidual cells and regulated by progesterone through HB-EGF/EGFR/ERK/STAT3 signaling pathway. E2F8 transcriptionally suppresses CDK1, thus triggering the polyploidization of decidual cells. E2F8-mediated polyploidization is a response to stresses which are accompanied by decidualization. Interestingly, polyploidization is not detected during human decidualization with the down-regulation of E2F8, indicating differential expression of E2F8 may lead to the difference of decidual cell polyploidization between mice and humans.

  13. Tree-average distances on certain phylogenetic networks have their weights uniquely determined.

    Science.gov (United States)

    Willson, Stephen J

    2012-01-01

    A phylogenetic network N has vertices corresponding to species and arcs corresponding to direct genetic inheritance from the species at the tail to the species at the head. Measurements of DNA are often made on species in the leaf set, and one seeks to infer properties of the network, possibly including the graph itself. In the case of phylogenetic trees, distances between extant species are frequently used to infer the phylogenetic trees by methods such as neighbor-joining. This paper proposes a tree-average distance for networks more general than trees. The notion requires a weight on each arc measuring the genetic change along the arc. For each displayed tree the distance between two leaves is the sum of the weights along the path joining them. At a hybrid vertex, each character is inherited from one of its parents. We will assume that for each hybrid there is a probability that the inheritance of a character is from a specified parent. Assume that the inheritance events at different hybrids are independent. Then for each displayed tree there will be a probability that the inheritance of a given character follows the tree; this probability may be interpreted as the probability of the tree. The tree-average distance between the leaves is defined to be the expected value of their distance in the displayed trees. For a class of rooted networks that includes rooted trees, it is shown that the weights and the probabilities at each hybrid vertex can be calculated given the network and the tree-average distances between the leaves. Hence these weights and probabilities are uniquely determined. The hypotheses on the networks include that hybrid vertices have indegree exactly 2 and that vertices that are not leaves have a tree-child.

  14. Physiological minimum temperatures for root growth in seven common European broad-leaved tree species.

    Science.gov (United States)

    Schenker, Gabriela; Lenz, Armando; Körner, Christian; Hoch, Günter

    2014-03-01

    Temperature is the most important factor driving the cold edge distribution limit of temperate trees. Here, we identified the minimum temperatures for root growth in seven broad-leaved tree species, compared them with the species' natural elevational limits and identified morphological changes in roots produced near their physiological cold limit. Seedlings were exposed to a vertical soil-temperature gradient from 20 to 2 °C along the rooting zone for 18 weeks. In all species, the bulk of roots was produced at temperatures above 5 °C. However, the absolute minimum temperatures for root growth differed among species between 2.3 and 4.2 °C, with those species that reach their natural distribution limits at higher elevations also tending to have lower thermal limits for root tissue formation. In all investigated species, the roots produced at temperatures close to the thermal limit were pale, thick, unbranched and of reduced mechanical strength. Across species, the specific root length (m g(-1) root) was reduced by, on average, 60% at temperatures below 7 °C. A significant correlation of minimum temperatures for root growth with the natural high elevation limits of the investigated species indicates species-specific thermal requirements for basic physiological processes. Although these limits are not necessarily directly causative for the upper distribution limit of a species, they seem to belong to a syndrome of adaptive processes for life at low temperatures. The anatomical changes at the cold limit likely hint at the mechanisms impeding meristematic activity at low temperatures.

  15. Comparative Characterization of Total Flavonol Glycosides and Terpene Lactones at Different Ages, from Different Cultivation Sources and Genders of Ginkgo biloba Leaves

    Directory of Open Access Journals (Sweden)

    Yong Qin

    2012-08-01

    Full Text Available The extract from Ginkgo biloba leaves has become a very popular plant medicine and herbal supplement for its potential benefit in alleviating symptoms associated with peripheral vascular disease, dementia, asthma and tinnitus. Most research on G. biloba leaves focus on the leaves collected in July and August from four to seven year-old trees, however a large number of leaves from fruit cultivars (trees older than 10 years are ignored and become obsolete after fruit harvest season (November. In this paper, we expand the tree age range (from one to 300 years and first comparatively analyze the total flavonol glycosides and terpene lactones at different ages, from different cultivation sources and genders of G. biloba leaves collected in November by using the validated HPLC-ELSD and HPLC-PDA methods. The results show that the contents of total terpene lactones and flavonol glycosides in the leaves of young ginkgo trees are higher than those in old trees, and they are higher in male trees than in female trees. Geographical factors appear to have a significant influence on the contents as well. These results will provide a good basis for the comprehensive utilization of G. biloba leaves, especially the leaves from fruit cultivars.

  16. Variability in radial sap flux density patterns and sapwood area among seven co-occurring temperate broad-leaved tree species.

    Science.gov (United States)

    Gebauer, Tobias; Horna, Viviana; Leuschner, Christoph

    2008-12-01

    Forest transpiration estimates are frequently based on xylem sap flux measurements in the outer sections of the hydro-active stem sapwood. We used Granier's constant-heating technique with heating probes at various xylem depths to analyze radial patterns of sap flux density in the sapwood of seven broad-leaved tree species differing in wood density and xylem structure. Study aims were to (1) compare radial sap flux density profiles between diffuse- and ring-porous trees and (2) analyze the relationship between hydro-active sapwood area and stem diameter. In all investigated species except the diffuse-porous beech (Fagus sylvatica L.) and ring-porous ash (Fraxinus excelsior L.), sap flux density peaked at a depth of 1 to 4 cm beneath the cambium, revealing a hump-shaped curve with species-specific slopes. Beech and ash reached maximum sap flux densities immediately beneath the cambium in the youngest annual growth rings. Experiments with dyes showed that the hydro-active sapwood occupied 70 to 90% of the stem cross-sectional area in mature trees of diffuse-porous species, whereas it occupied only about 21% in ring-porous ash. Dendrochronological analyses indicated that vessels in the older sapwood may remain functional for 100 years or more in diffuse-porous species and for up to 27 years in ring-porous ash. We conclude that radial sap flux density patterns are largely dependent on tree species, which may introduce serious bias in sap-flux-derived forest transpiration estimates, if non-specific sap flux profiles are assumed.

  17. Cyclin G1 inhibits the proliferation of mouse endometrial stromal cell in decidualization

    Directory of Open Access Journals (Sweden)

    Xu Qian

    2017-01-01

    Full Text Available Uterine stromal cell decidualization is a dynamic physiological process in which cell proliferation, differentiation and apoptosis are orchestrated and occur in a temporal and cell-specific manner. This process is important for successful embryo implantation. Many cell-cycle regulators are involved in decidualization. The protein cyclin G1 is a unique regulator of the cell cycle with dual functions in cell proliferation. It was reported that cyclin G1 is expressed in mouse uterine stromal cells during the period of peri-implantation. To prove the function of cyclin G1 in mouse uterine stromal cells during this period, immunohistochemistry was used to stain mouse uterine tissues on days 4-8 of pregnancy. The results showed obvious spatial and temporal expression of cyclin G1 in uterine stromal cells, and that it is expressed in the cells of the primary decidual zone (PDZ on day 5 and secondary decidual zone (SDZ on days 6 and 7, when the stromal cells experienced active proliferation and differentiation was initiated. Applying the decidualization model of cultured primary stromal cells in vitro, we further revealed that the expression of cyclin G1 is associated with decidualization of stromal cells induced by medroxyprogesterone acetate (MPA and estradiol-17β (E2. RNA interference was used for the knockdown of cyclin G1 in the induced decidual cells. Flow cytometry analysis indicated that the proportion of cells in the S stage was increased, and decreased in the G2/M phase. Our study indicates that cyclin G1, as a negative regulator of the cell cycle, plays an important role in the process of decidualization in mouse uterine stromal cells by inhibiting cell-cycle progression.

  18. Climate change impacts on tree ranges: model intercomparison facilitates understanding and quantification of uncertainty.

    Science.gov (United States)

    Cheaib, Alissar; Badeau, Vincent; Boe, Julien; Chuine, Isabelle; Delire, Christine; Dufrêne, Eric; François, Christophe; Gritti, Emmanuel S; Legay, Myriam; Pagé, Christian; Thuiller, Wilfried; Viovy, Nicolas; Leadley, Paul

    2012-06-01

    Model-based projections of shifts in tree species range due to climate change are becoming an important decision support tool for forest management. However, poorly evaluated sources of uncertainty require more scrutiny before relying heavily on models for decision-making. We evaluated uncertainty arising from differences in model formulations of tree response to climate change based on a rigorous intercomparison of projections of tree distributions in France. We compared eight models ranging from niche-based to process-based models. On average, models project large range contractions of temperate tree species in lowlands due to climate change. There was substantial disagreement between models for temperate broadleaf deciduous tree species, but differences in the capacity of models to account for rising CO(2) impacts explained much of the disagreement. There was good quantitative agreement among models concerning the range contractions for Scots pine. For the dominant Mediterranean tree species, Holm oak, all models foresee substantial range expansion. © 2012 Blackwell Publishing Ltd/CNRS.

  19. Transport and concentration of abscisic acid (ABA) and auxin (IAA) in deciduous and coniferous trees. Transport und Gehalt von Abscisinsaeure (ABA) und Auxin (IAA) in Laub- und Nadelblaettern

    Energy Technology Data Exchange (ETDEWEB)

    Hartung, W.

    1988-09-01

    Abscisic acid and indoleacetic acid were chosen to examine whether intact deciduous and coniferous tissues from spruce, hemlock fir, spinage, barley and sorrel or isolated mesophyll protoplasts from barley and closing cell preparations from Valerianella locusta are affected by sulphur dioxide in terms of changes in the concentration, transportation and distribution of such plant hormones. The distribution of phytohormones like ABA and IAA over the individual cell compartments is determined by the different pH gradients of the latter. Owing to their acidity these hormones are accumulated in alkaline cell inclusion bodies like chloroplasts and cytosol. Potentially acid air pollutants like SO{sub 2} and NO{sub x} lead to acidification of previously alkaline cell compartments, due to which fact the cellular pH gradients are reduced. This, in turn, gives rise to a redistribution of phytohormones to the effect that certain target cells such as closing cells of leaves or meristem cells come under the influence of altered hormone concentrations and compositions. This is bound to affect the processes controlling the development, growth and stress behaviour of plants. (orig.) With 55 refs., 2 tabs., 16 figs.

  20. The mono - and sesquiterpene content of aphid-induced galls on Pistacia palaestina is not a simple reflection of their composition in intact leaves.

    Science.gov (United States)

    Rand, Karin; Bar, Einat; Ben-Ari, Matan; Lewinsohn, Efraim; Inbar, Moshe

    2014-06-01

    Pistacia palaestina Boiss. (Anacardiaceae), a sibling species of P. terebinthus also known as turpentine tree or terebinth tree, is common in the Levant region. The aphid Baizongia pistaciae L. manipulates the leaves of the plant to form large galls, which provide both food and protection for its developing offspring. We analyzed the levels and composition of mono-and sesquiterpenes in both leaves and galls of ten naturally growing trees. Our results show that monoterpene hydrocarbons are the main constituents of P. palaestina leaves and galls, but terpene levels and composition vary among trees. Despite this inter-tree variation, terpene levels and compositions in galls from different trees resemble each other more than the patterns displayed by leaves from the same trees. Generally, galls contain 10 to 60 fold higher total terpene amounts than leaves, especially of the monoterpenes α-pinene and limonene. Conversely, the leaves generally accumulate more sesquiterpenes, in particular E-caryophyllene, germacrene D and δ-cadinene, in comparison to galls. Our results clearly show that the terpene pattern in the galls is not a simple reflection of that of the leaves and suggest that aphids have a strong impact on the metabolism of their host plant, possibly for their own defense.

  1. Border trees of complex networks

    International Nuclear Information System (INIS)

    Villas Boas, Paulino R; Rodrigues, Francisco A; Travieso, Gonzalo; Fontoura Costa, Luciano da

    2008-01-01

    The comprehensive characterization of the structure of complex networks is essential to understand the dynamical processes which guide their evolution. The discovery of the scale-free distribution and the small-world properties of real networks were fundamental to stimulate more realistic models and to understand important dynamical processes related to network growth. However, the properties of the network borders (nodes with degree equal to 1), one of its most fragile parts, remained little investigated and understood. The border nodes may be involved in the evolution of structures such as geographical networks. Here we analyze the border trees of complex networks, which are defined as the subgraphs without cycles connected to the remainder of the network (containing cycles) and terminating into border nodes. In addition to describing an algorithm for identification of such tree subgraphs, we also consider how their topological properties can be quantified in terms of their depth and number of leaves. We investigate the properties of border trees for several theoretical models as well as real-world networks. Among the obtained results, we found that more than half of the nodes of some real-world networks belong to the border trees. A power-law with cut-off was observed for the distribution of the depth and number of leaves of the border trees. An analysis of the local role of the nodes in the border trees was also performed

  2. The local origin of decidual cells in pregnant mice

    International Nuclear Information System (INIS)

    Zorn, T.M.T.; Abrahamsohn, P.A.; Mariano, M.

    1986-01-01

    In order to evaluate the participation of extrauterine cells in the formation of mouse antimesometrial decidua, [ 3 H]-thymidine was administered ip on days 1, 5 and 6 of pregnancy and the animals were killed 1 h afterwards. A second group of mice received four ip injections of [ 3 H]-thymidine at 6-h intervals on the 1st day of pregnancy and were killed on the 2nd, 5th or 6th day of pregnancy. A third group of virgin mice in estrus received [ 3 H]-thymidine ip four times at 6-h intervals and was killed 96 h after the first injection. Radioautographs of the uteri showed that few endometrial stomal cells were labelled on the 1st and 2nd day of pregnancy. Although many decidual cells incorporated thymidine on the 5th and 6th day of pregnancy in pulse-labelled animals, only few labelled decidual cells were found on the 5th and 6th day of pregnancy in animals that received several injections of thymidine on the 1st and 2nd day of pregnancy. These results indicate that the antimesometrial decidual cells that develop at the beginning of pregnancy are mostly of local origin. The short-term migration of extraneous cells into the uterus to participate in decidualization is not supported by these data. (author) [pt

  3. Spectral Reflectance and Vegetation Index Changes in Deciduous Forest Foliage Following Tree Removal: Potential for Deforestation Monitoring

    Science.gov (United States)

    Peng, D.; Hu, Y.; Li, Z.

    2016-05-01

    It is important to detect and quantify deforestation to guide strategic decisions regarding environment, socioeconomic development, and climate change. In the present study, we conducted a field experiment to examine spectral reflectance and vegetation index changes in poplar and locust tree foliage with different leaf area indices over the course of three sunny days, following tree removal from the canopy. The spectral reflectance of foliage from harvested trees was measured using an ASD FieldSpec Prospectroradiometer; synchronous meteorological data were also obtained. We found that reflectance in short-wave infrared and red-edge reflectance was more time sensitive after tree removal than reflectance in other spectral regions, and that the normalized difference water index (NDWI) and the red-edge chlorophyll index (CIRE) were the preferred indicators of these changes from several indices evaluated. Synthesized meteorological environments were found to influence water and chlorophyll contents after tree removal, and this subsequently changed the spectral canopy reflectance. Our results indicate the potential for such tree removal to be detected with NDWI or CIRE from the second day of a deforestation event.

  4. Flowering Trees

    Indian Academy of Sciences (India)

    Berrya cordifolia (Willd.) Burret (Syn. B. ammonilla Roxb.) – Trincomali Wood of Tiliaceae is a tall evergreen tree with straight trunk, smooth brownish-grey bark and simple broad leaves. Inflorescence is much branched with white flowers. Stamens are many with golden yellow anthers. Fruit is a capsule with six spreading ...

  5. Flowering Trees

    Indian Academy of Sciences (India)

    Andira inermis (wright) DC. , Dog Almond of Fabaceae is a handsome lofty evergreen tree. Leaves are alternate and pinnately compound with 4–7 pairs of leaflets. Flowers are fragrant and are borne on compact branched inflorescences. Fruit is ellipsoidal one-seeded drupe that is peculiar to members of this family.

  6. Flowering Trees

    Indian Academy of Sciences (India)

    Guaiacum officinale L. (LIGNUM-VITAE) of Zygophyllaceae is a dense-crowned, squat, knobbly, rough and twisted medium-sized ev- ergreen tree with mottled bark. The wood is very hard and resinous. Leaves are compound. The leaflets are smooth, leathery, ovate-ellipti- cal and appear in two pairs. Flowers (about 1.5.

  7. Forestiera acuminata (Michx.)

    Science.gov (United States)

    K.F. Connor

    2004-01-01

    Swamp privet is a deciduous shrub or small, open-crowned tree, occasionally reaching 10 m in height but more often averaging 1.5 to 2.5 m. It is commonly multi-trunked. The bark ranges from gray to dark brown in color and is either smooth or ridged. Twigs are light brown, glabrous, and have conspicuous lenticels. Leaves are simple, opposite, and a dull, yellowish green...

  8. Red Reveals Branch Die-back in Norway Maple Acer platanoides

    Science.gov (United States)

    Sinkkonen, Aki

    2008-01-01

    Background and Aims Physiological data suggest that autumn leaf colours of deciduous trees are adaptations to environmental stress. Recently, the evolution of autumn colouration has been linked to tree condition and defence. Most current hypotheses presume that autumn colours vary between tree individuals. This study was designed to test if within-tree variation should be taken into account in experimental and theoretical research on autumn colouration. Methods Distribution of red autumn leaf colours was compared between partially dead and vigorous specimens of Norway maple (Acer platanoides) in a 3-year study. In August, the amount of reddish foliage was estimated in pairs of partially dead and control trees. Within-tree variation in the distribution of reddish leaves was evaluated. Leaf nitrogen and carbon concentrations were analysed. Key Results Reddish leaf colours were more frequent in partially dead trees than in control trees. Reddish leaves were evenly distributed in control trees, while patchiness of red leaf pigments was pronounced in partially dead trees. Large patches of red leaves were found beneath or next to dead tree parts. These patches reoccurred every year. Leaf nitrogen concentration was lower in reddish than in green leaves but the phenomenon seemed similar in both partially dead and control trees. Conclusions The results suggest that red leaf colouration and branch condition are interrelated in Norway maple. Early reddish colours may be used as an indication of leaf nitrogen and carbon levels but not as an indication of tree condition. Studies that concentrate on entire trees may not operate at an optimal level to detect the evolutionary mechanisms behind autumnal leaf colour variation. PMID:18567914

  9. Nutritional evaluation of leaves of some salt-tolerant tree species by assessing, in vitro, the ruminal microbial nitrogen and fermentation characteristics utilizing "1"5N tracer and gas production techniques

    International Nuclear Information System (INIS)

    Al-Masri, M.R.

    2014-04-01

    Leaves of some salt-tolerant tree species (Tamarix articulata Vahl., Tamarix aphylla (L) Karst, Acacia ampliceps Maslin, Casuarina equisetifolia L, Parkinsonia aculeate L, Eucaliptus camaldulensis Dahnhard) were evaluated in terms of microbial nitrogen (MN) and biomass (MBM) production after incubation with rumen fluid and 15N-tracer for 96 h in the absence or presence of polyethylene glycol (PEG, 6000). The characteristics of fermentation (initial gas produced from soluble fraction; a, gas production during incubation which produced from insoluble but fermentable fraction; b, potential gas production; a + b, fractional rate of gas production per hour; c) were assessed using an in vitro incubation technique with rumen fluid. Effective degradability (ED), short chain fatty acids (SCFA) and predicted daily intake (Y) were also estimated in leaves of the experimental tree species.The a + b values (mL/g DM) were highest (P<0.05) in A. ampliceps (191), lowest in T. articulate and C. equisetifolia (119), and intermediate in T. aphylla, E. camaldulensis and P. aculeate (158). E. camaldulensis, A. ampliceps and P. aculeate had higher (P<0.05) fractional rate of gas production (0.080/h) than other species (0.061/h). There was a positive correlation between SCFA concentrations and c and a + b values. The ratios of MN and MBM to effective degraded substrate and the values of MN and MBM were significantly higher (P<0.05) in P. aculeate and A. ampliceps compared with other species. Microbial nitrogen and MBM production were positively correlated with a + b, ED and SCFA.The addition of PEG to the plant samples incubated with rumen fluid at a ratio of 2:1 PEG: substrate increased the values of gas production, characteristics of fermentation, MN, MBM, SCFA, ED and Y. The response of leaves of the experimental tree species to PEG treatment in terms of increased gas production varied between species and tended to decline as incubation progressed, with the highest increase during the

  10. Detection of heavy metals in leaves of melia azedarach and eucalyptus citriodora as biomonitring tools in the region of Quetta valley

    International Nuclear Information System (INIS)

    Khattak, M.I.

    2012-01-01

    The concentrations of heavy metals viz., Cd, Cr, Cu, Fe, Mn, Ni, Pb and Zn in leaves of two tree species, Melia azedarach and Eucalyptus citriodora (Safeda) from different sampling sites at urban areas in Quetta city , were measured. Correlation between elements and the use of tree leaves as indicators of environmental pollution was investigated. The results show that the higher concentrations of heavy metals in Eucalyptus leaves of the areas of the Hudda, Barori and Mashraqi by Pass and in the areas with dense transportation activities are in function. So this preliminary study presents scientific basis to establish the applicability of the tree leaves as bio-monitoring tool for the rapid evaluation of the pollution status in the Quetta city by analyzing heavy metals concentration in the tree leaves. (author)

  11. High density of tree-cavities and snags in tropical dry forest of western Mexico raises questions for a latitudinal gradient.

    Directory of Open Access Journals (Sweden)

    Leopoldo Vázquez

    Full Text Available It has been suggested that a latitudinal gradient exists of a low density of snags and high density of naturally-formed tree-cavities in tropical vs. temperate forests, though few cavities may have characteristics suitable for nesting by birds. We determined snag and cavity density, characteristics, and suitability for birds in a tropical dry forest biome of western Mexico, and evaluated whether our data fits the trend of snag and cavity density typically found in tropical moist and wet forests. We established five 0.25-ha transects to survey and measure tree-cavities and snags in each of three vegetation types of deciduous, semi-deciduous, and mono-dominant Piranhea mexicana forest, comprising a total of 3.75 ha. We found a high density of 77 cavities/ha, with 37 cavities suitable for birds/ha, where density, and characteristics of cavities varied significantly among vegetation types. Lowest abundance of cavities occurred in deciduous forest, and these were in smaller trees, at a lower height, and with a narrower entrance diameter. Only 8.6% of cavities were excavated by woodpeckers, and only 11% of cavities were occupied, mainly by arthropods, though 52% of all cavities were unsuitable for birds. We also found a high density of 56 snags/ha, with greatest density in deciduous forest (70 snags/ha, though these were of significantly smaller diameter, and snags of larger diameter were more likely to contain cavities. The Chamela-Cuixmala tropical dry forest had the highest density of snags recorded for any tropical or temperate forest, and while snag density was significantly correlated with mean snag dbh, neither latitude nor mean dbh predicted snag density in ten forest sites. The high spatial aggregation of snag and cavity resources in tropical dry forest may limit their availability, particularly for large-bodied cavity adopters, and highlights the importance of habitat heterogeneity in providing resources for primary and secondary cavity-nesters.

  12. High density of tree-cavities and snags in tropical dry forest of western Mexico raises questions for a latitudinal gradient.

    Science.gov (United States)

    Vázquez, Leopoldo; Renton, Katherine

    2015-01-01

    It has been suggested that a latitudinal gradient exists of a low density of snags and high density of naturally-formed tree-cavities in tropical vs. temperate forests, though few cavities may have characteristics suitable for nesting by birds. We determined snag and cavity density, characteristics, and suitability for birds in a tropical dry forest biome of western Mexico, and evaluated whether our data fits the trend of snag and cavity density typically found in tropical moist and wet forests. We established five 0.25-ha transects to survey and measure tree-cavities and snags in each of three vegetation types of deciduous, semi-deciduous, and mono-dominant Piranhea mexicana forest, comprising a total of 3.75 ha. We found a high density of 77 cavities/ha, with 37 cavities suitable for birds/ha, where density, and characteristics of cavities varied significantly among vegetation types. Lowest abundance of cavities occurred in deciduous forest, and these were in smaller trees, at a lower height, and with a narrower entrance diameter. Only 8.6% of cavities were excavated by woodpeckers, and only 11% of cavities were occupied, mainly by arthropods, though 52% of all cavities were unsuitable for birds. We also found a high density of 56 snags/ha, with greatest density in deciduous forest (70 snags/ha), though these were of significantly smaller diameter, and snags of larger diameter were more likely to contain cavities. The Chamela-Cuixmala tropical dry forest had the highest density of snags recorded for any tropical or temperate forest, and while snag density was significantly correlated with mean snag dbh, neither latitude nor mean dbh predicted snag density in ten forest sites. The high spatial aggregation of snag and cavity resources in tropical dry forest may limit their availability, particularly for large-bodied cavity adopters, and highlights the importance of habitat heterogeneity in providing resources for primary and secondary cavity-nesters.

  13. Modified Willet's appliance for bilateral loss of multiple deciduous molars: a case report.

    Science.gov (United States)

    Dhindsa, A; Pandit, I K

    2008-09-01

    No other factor plays a more significant role in preventive and interceptive dentistry than the preservation of deciduous dentition till its normal time of exfoliation. Premature loss of a deciduous tooth or a group of teeth might lead to wide range of implications. When the deciduous second molar is lost before the eruption of first permanent molar, intra-alveolar type of space maintainer is indicated. But in cases of bilateral loss of these teeth the conventional design generally poses a variety of problems. Thus, the conventional designs are required to be modified according to the needs of the patient. Therefore, this paper describes an entirely new design of the Willet's appliance in cases of bilateral loss of deciduous molars before the eruption of first permanent molar.

  14. Assessment of the urban trees health status on the base of nutrient and pigment content in their leaves

    Directory of Open Access Journals (Sweden)

    SLAVEYA PETROVA

    2014-04-01

    Full Text Available Town settlements have different load level by emissions originated mostly from transport, industry and heating system. Their environmental and climate conditions are more or less changed that effect to growth, physiology and vigor of woody plants at the city public vegetation areas. Our study on determining the impact of urban environment on the tree health status was focused on the quantities of nutrients and main components of the pigment complex – chlorophyll a, chlorophyll b and carotenoids. Leaves of Acer platanoides L., Aesculus hippocastanum L. and Betula pendula Roth. were sampled from urban areas with different type of anthropogenic pressure in the town of Plovdiv (Bulgaria. Concentrations of the elements Ca, K, Mg, N, Na, P, and S were analyzed by ICP-MS. Health condition of trees in the city parks and suburban areas was acceptable, but in the central part and close to the industrial area it was non-satisfactory. This preliminary research pointed ecophysiological tools as useful to develop new criteria for sustainable urban arboriculture, including species selection (based on stress tolerance criteria, nursery hardening and preconditioning, and care after planting.

  15. Modeling Ecosystem Services for Park Trees: Sensitivity of i-Tree Eco Simulations to Light Exposure and Tree Species Classification

    Directory of Open Access Journals (Sweden)

    Rocco Pace

    2018-02-01

    Full Text Available Ecosystem modeling can help decision making regarding planting of urban trees for climate change mitigation and air pollution reduction. Algorithms and models that link the properties of plant functional types, species groups, or single species to their impact on specific ecosystem services have been developed. However, these models require a considerable effort for initialization that is inherently related to uncertainties originating from the high diversity of plant species in urban areas. We therefore suggest a new automated method to be used with the i-Tree Eco model to derive light competition for individual trees and investigate the importance of this property. Since competition depends also on the species, which is difficult to determine from increasingly used remote sensing methodologies, we also investigate the impact of uncertain tree species classification on the ecosystem services by comparing a species-specific inventory determined by field observation with a genus-specific categorization and a model initialization for the dominant deciduous and evergreen species only. Our results show how the simulation of competition affects the determination of carbon sequestration, leaf area, and related ecosystem services and that the proposed method provides a tool for improving estimations. Misclassifications of tree species can lead to large deviations in estimates of ecosystem impacts, particularly concerning biogenic volatile compound emissions. In our test case, monoterpene emissions almost doubled and isoprene emissions decreased to less than 10% when species were estimated to belong only to either two groups instead of being determined by species or genus. It is discussed that this uncertainty of emission estimates propagates further uncertainty in the estimation of potential ozone formation. Overall, we show the importance of using an individual light competition approach and explicitly parameterizing all ecosystem functions at the

  16. Flowering Trees

    Indian Academy of Sciences (India)

    Muntingia calabura L. (Singapore cherry) of. Elaeocarpaceae is a medium size handsome ever- green tree. Leaves are simple and alternate with sticky hairs. Flowers are bisexual, bear numerous stamens, white in colour and arise in the leaf axils. Fruit is a berry, edible with several small seeds embedded in a fleshy pulp ...

  17. Decidual vascularization and the expression of angiogenic growth factors and proteases in first trimester spontaneous abortions

    NARCIS (Netherlands)

    Plaisier, M.; Dennert, I.; Rost, E.; Koolwijk, P.; Hinsbergh, V.W.M. van; Helmerhorst, F.M.

    2009-01-01

    BACKGROUND : Decidual vascular development is important for implantation. This study analysed decidual vascular adaptation to implantation in correlation with miscarriage in decidual secretory endometrium (DSE), decidua parietalis (DP) and decidua basalis (DB) of miscarriage patients and matched

  18. Effects of pedunculate oak tree vitality on gypsy moth preference and performance

    Directory of Open Access Journals (Sweden)

    Milanović Slobodan

    2014-01-01

    Full Text Available Gypsy moths and powdery mildew play a significant role in oak decline processes. However, information is lacking on the effects on the gypsy moth of impaired tree vitality caused by defoliation or parasite infection. We assessed how pedunculate oak leaves collected from vigorous, declining, and infected trees influenced gypsy moth preference and performance (growth and nutritional indices. We found a negative effect of powdery mildew-infected leaves on gypsy moth performance, while declining trees had positive effects on gypsy moth performance and preference. All examined parameters of larvae fed declining oak leaves were higher than those of larvae fed vigorous oak leaves. Increased growth on declining oak leaves was caused by both higher consumption and more efficient food utilization. The results of this research could help us to better understand multitrophic interactions in complex communities such as oak forests. [Projekat Ministarstva nauke Republike Srbije, br. 43007: Studying climate change and its influence on the environment: impacts, adaptation and mitigation

  19. Supragingival Microbial Profiles of Permanent and Deciduous Teeth in Children with Mixed Dentition.

    Directory of Open Access Journals (Sweden)

    Weihua Shi

    Full Text Available The present study was designed to investigate the microbial profiles of teeth in different locations in mixed-dentition-stage children, and to compare the microbiomes of permanent and deciduous teeth in the same healthy oral cavity.Supragingival plaque samples of teeth in various locations-the first permanent molars, deciduous molars, deciduous canines and incisors and permanent incisors-were collected from 20 healthy mixed-dentition-stage children with 10-12 permanent teeth erupted. Plaque DNA was extracted, and the V3-V4 hypervariable region of the bacterial 16S rRNA gene was amplified and subjected to sequencing.On average, 18,051 high-quality sequences per sample were generated. Permanent tooth sites tended to host more diverse bacterial communities than those of deciduous tooth sites. A total of 12 phyla, 21 classes, 38 orders, 66 families, 74 genera were detected ultimately. Five predominant phyla (Proteobacteria, Firmicutes, Bacteroidetes, Fusobacteria and Actinobacteria were highly variable among sites. Of 26 genera with a mean relative abundance of >0.1%, 16 showed significant differences in relative abundance among the groups. More than 20% of the total operational taxonomical units were detected only in permanent or deciduous teeth. The variation in the microbial community composition was due mainly to permanent teeth being enriched in Actinomyces and deciduous teeth in Treponema. The core microbiome of supragingival plaque in mixed dentition comprised 19 genera with complex correlationships.Our results suggest differences in microbial diversity and composition between permanent and deciduous teeth sites in mixed dentition. Moreover, the core microbiome of these sites was determined. These findings enhance our understanding of the development of the native oral microbiota with age.

  20. Foliar accumulation of polycyclic aromatic hydrocarbons in native tree species from the Atlantic Forest (SE-Brazil).

    Science.gov (United States)

    Dias, Ana Paula L; Rinaldi, Mirian C S; Domingos, Marisa

    2016-02-15

    Polycyclic aromatic hydrocarbons (PAHs) are toxic to living organisms. They can accumulate on foliar surfaces due to their affinity with apolar organic compounds, which enables the use of native plant species as sentinels of atmospheric PAH deposition in polluted ecosystems. The present study extends the knowledge about this subject in the tropical region by focusing on the PAH accumulation in the foliage of dominant tree species (Astronium graveolens, Croton floribundus, Piptadenia gonoacantha) in four remnants of Semi-deciduous Atlantic Forest surrounded by diversified sources of PAHs and located in the cities of Campinas, Paulínia, Holambra and Cosmópilis (central-eastern part of São Paulo State, SE-Brazil). Leaves of the tree species were collected in the forest remnants during the wet and dry seasons (2011 to 2013). All samples were analyzed by high performance liquid chromatography (HPLC) coupled to a fluorescence detector for identification of 14 PAHs. The native tree species showed distinct capacities to accumulate PAHs. All of them accumulated proportionally more light PAHs than heavy PAHs, mainly during the dry period. P. gonoacantha was the most effective accumulator species. Higher accumulations of most of the PAHs occurred during the dry periods. The predominance of moderately (1 ≤ EF forest remnants indicated that vehicular sources were widely distributed in the entire region. The predominance of the moderate to high enrichment of ACE in leaf samples from the forest remnants located in Paulínia, Holambra and Cosmópolis indicated that they were also affected by emissions from petrochemical industries. Copyright © 2015 Elsevier B.V. All rights reserved.

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

    International Nuclear Information System (INIS)

    Nunn, Angela J.; Wieser, Gerhard; Metzger, Ursula; Loew, Markus; Wipfler, Philip; Haeberle, Karl-Heinz; Matyssek, Rainer

    2007-01-01

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

  2. Quantifying the Accuracy of Digital Hemispherical Photography for Leaf Area Index Estimates on Broad-Leaved Tree Species.

    Science.gov (United States)

    Gilardelli, Carlo; Orlando, Francesca; Movedi, Ermes; Confalonieri, Roberto

    2018-03-29

    Digital hemispherical photography (DHP) has been widely used to estimate leaf area index (LAI) in forestry. Despite the advancement in the processing of hemispherical images with dedicated tools, several steps are still manual and thus easily affected by user's experience and sensibility. The purpose of this study was to quantify the impact of user's subjectivity on DHP LAI estimates for broad-leaved woody canopies using the software Can-Eye. Following the ISO 5725 protocol, we quantified the repeatability and reproducibility of the method, thus defining its precision for a wide range of broad-leaved canopies markedly differing for their structure. To get a complete evaluation of the method accuracy, we also quantified its trueness using artificial canopy images with known canopy cover. Moreover, the effect of the segmentation method was analysed. The best results for precision (restrained limits of repeatability and reproducibility) were obtained for high LAI values (>5) with limits corresponding to a variation of 22% in the estimated LAI values. Poorer results were obtained for medium and low LAI values, with a variation of the estimated LAI values that exceeded the 40%. Regardless of the LAI range explored, satisfactory results were achieved for trees in row-structured plantations (limits almost equal to the 30% of the estimated LAI). Satisfactory results were achieved for trueness, regardless of the canopy structure. The paired t -test revealed that the effect of the segmentation method on LAI estimates was significant. Despite a non-negligible user effect, the accuracy metrics for DHP are consistent with those determined for other indirect methods for LAI estimates, confirming the overall reliability of DHP in broad-leaved woody canopies.

  3. Quantifying the Accuracy of Digital Hemispherical Photography for Leaf Area Index Estimates on Broad-Leaved Tree Species

    Directory of Open Access Journals (Sweden)

    Carlo Gilardelli

    2018-03-01

    Full Text Available Digital hemispherical photography (DHP has been widely used to estimate leaf area index (LAI in forestry. Despite the advancement in the processing of hemispherical images with dedicated tools, several steps are still manual and thus easily affected by user’s experience and sensibility. The purpose of this study was to quantify the impact of user’s subjectivity on DHP LAI estimates for broad-leaved woody canopies using the software Can-Eye. Following the ISO 5725 protocol, we quantified the repeatability and reproducibility of the method, thus defining its precision for a wide range of broad-leaved canopies markedly differing for their structure. To get a complete evaluation of the method accuracy, we also quantified its trueness using artificial canopy images with known canopy cover. Moreover, the effect of the segmentation method was analysed. The best results for precision (restrained limits of repeatability and reproducibility were obtained for high LAI values (>5 with limits corresponding to a variation of 22% in the estimated LAI values. Poorer results were obtained for medium and low LAI values, with a variation of the estimated LAI values that exceeded the 40%. Regardless of the LAI range explored, satisfactory results were achieved for trees in row-structured plantations (limits almost equal to the 30% of the estimated LAI. Satisfactory results were achieved for trueness, regardless of the canopy structure. The paired t-test revealed that the effect of the segmentation method on LAI estimates was significant. Despite a non-negligible user effect, the accuracy metrics for DHP are consistent with those determined for other indirect methods for LAI estimates, confirming the overall reliability of DHP in broad-leaved woody canopies.

  4. Flowering Trees

    Indian Academy of Sciences (India)

    Canthium parviflorum Lam. of Rubiaceae is a large shrub that often grows into a small tree with conspicuous spines. Leaves are simple, in pairs at each node and are shiny. Inflorescence is an axillary few-flowered cymose fascicle. Flowers are small (less than 1 cm across), 4-merous and greenish-white. Fruit is ellipsoid ...

  5. Flowering Trees

    Indian Academy of Sciences (India)

    mid-sized slow-growing evergreen tree with spreading branches that form a dense crown. The bark is smooth, thick, dark and flakes off in large shreds. Leaves are thick, oblong, leathery and bright red when young. The female flowers are drooping and are larger than male flowers. Fruit is large, red in color and velvety.

  6. Initial response to understory plant diversity and overstory tree diameter growth to a green tree retention harvest

    Science.gov (United States)

    Malcolm North; Jiquan Chen; Gordon Smith; Lucy Krakowlak; Jerry Franklin

    1996-01-01

    The increasing use of harvest techniques other than clearcutting in forests west of the Cascade mountains has created an urgent need to understand the effects of these practices on ecosystem species composition and structure. One common alternative, "green tree retention" (GTR), leaves some live trees on a harvest site to more closely mimic a moderate-...

  7. Thermal analysis of wood of the main tree species of Central Siberia

    Directory of Open Access Journals (Sweden)

    S. R. Loskutov

    2015-12-01

    Full Text Available Thermal decomposition of wood from coniferous and deciduous species of Siberia has been studied using thermogravimetry (TG and differential scanning calorimetry (DSC. The tree species were larch Larix sibirica Ledeb., Scots pine Pinus sylvestris L., spruce Picea obovata Ledeb., fir Abies sibirica Ledeb., Siberian pine Pinus sibirica Du Tour., birch Betula pendula Roth., and aspen Populus tremula L. Thermal analysis of wood samples was carried out under oxidative (air and inert (argon atmospheres from 25 to 700 °С at heating rates 10, 20, 40 °С • min–1 (TG/DTG and from 25 to 590 °С at heating rates 10, 40 °С • min–1 (DSC. The stages of thermal decomposition, the temperature intervals, the mass loss, the mass loss rate, the temperature of DTG/DSC peaks, and heating effects were determined for each tree species. The kinetic thermal degradation parameters of wood were obtained by the Broido and Ozawa–Flynn–Wall models. The wood of coniferous and deciduous species of Siberia was characterized on the base of analysis of activation energy values at various stages of thermal decomposition and the relations of activation energy on conversion level of wood substance of different tree species, and also the comparison of mass loss at the same stages of thermal destruction, heating effects, residual mass and other parameters of TG/DTG, DSC. In our opinion, the results of this work present interest for researchers and specialists in the field of forest pyrology, wood science, dendrochemistry.

  8. Leaf traits show different relationships with shade tolerance in moist versus dry tropical forests.

    Science.gov (United States)

    Poorter, Lourens

    2009-03-01

    Shade tolerance is the central paradigm for understanding forest succession and dynamics, but there is considerable debate as to what the salient features of shade tolerance are, whether adult leaves show similar shade adaptations to seedling leaves, and whether the same leaf adaptations are found in forests under different climatic control. Here, adult leaf and metamer traits were measured for 39 tree species from a tropical moist semi-evergreen forest (1580 mm rain yr(-1)) and 41 species from a dry deciduous forest (1160 mm yr(-1)) in Bolivia. Twenty-six functional traits were measured and related to species regeneration light requirements.Adult leaf traits were clearly associated with shade tolerance. Different, rather than stronger, shade adaptations were found for moist compared with dry forest species. Shade adaptations exclusively found in the evergreen moist forest were related to tough and persistent leaves, and shade adaptations in the dry deciduous forest were related to high light interception and water use.These results suggest that, for forests differing in rainfall seasonality, there is a shift in the relative importance of functional leaf traits and performance trade-offs that control light partitioning. In the moist evergreen forest leaf traits underlying the growth-survival trade-off are important, whereas in the seasonally deciduous forest leaf traits underlying the growth trade-off between low and high light might become important.

  9. [Early deciduous tooth loss--the mature or immature eruption of their permanent successors].

    Science.gov (United States)

    Czecholinski, J A; Kahl, B; Schwarze, C W

    1994-04-01

    On the basis of 147 panoramic radiographs of 49 patients, this study investigated the influence of the premature loss of deciduous teeth on the formation of their permanent successors at the time of their eruption. Furthermore the study investigated the eruptive movement of the successor teeth at the time of eruption. In addition to detecting the accelerated emergence of still immature successor premolars, the study also determined that the extraction ot the deciduous molars before the age of eight years delayed the eruption of the permanent successors given the absence of an infected deciduous tooth with abscess formation. In relation to the eruptive movement of the permanent molars due to the premature loss of the second deciduous molar, the study ascertained a mesial movement of the first permanent molars and an accelerated eruption of the second permanent molars.

  10. Some forest trees for honeydew honey production in Turkey

    Directory of Open Access Journals (Sweden)

    S. Ünal

    2017-08-01

    Full Text Available Honey is an important source of nutrients and energy and an effective remedy against various human diseases. Honeydew honey is produced from honeydew of phloem-feeders that honeybees gather. In this study, we focused on honeydew producers and diversity of host tree species which are involved in honeydew production in Turkey. A total of 24 honeydew producers by host tree species are identified in Turkey. Of these, 13 coniferous trees and 11 deciduous trees. The main honeydew producer in Turkey is a scale insect, Marchalina hellenica Gennadius (Hemiptera: Margarodidae living mainly on pines (Turkish red pine, Aleppo pine, and rarely on stone pine, Anatolian black pine and Scots pine. Honeydew producer insects can be treated as serious pests of conifer and broadleaf trees. The aphids and the scale insects such as Ceroplastes floridensis, Cinara cedri, C. laportei, Eulachnus rileyi, Icerya purchase, Kermes vermilio, Lichtensia viburni and Saissetia oleae are known as pests in several European, Asian and African countries. Despite their potential harm to their host plants, insect species producing honeydew play an important role in honey production in Turkey. Turkish honey production is exported to EU countries and, furthermore beekeeping is an important part of agricultural sector in Turkey.

  11. Some aspects of the ecology of the Indian Giant Squirrel Ratufa indica (Erxleben, 1777 in the tropical forests of Mudumalai Wildlife Sanctuary, southern India and their conservation implications

    Directory of Open Access Journals (Sweden)

    N. Baskaran

    2011-07-01

    Full Text Available The Indian Giant Squirrel Ratufa indica, an endemic species to India, is widely distributed from the evergreen to moist and dry deciduous forests of Western and Eastern Ghats and the central Indian hills. We studied its population distribution, activity, feeding, ranging and nesting behaviour across three major habitats in the tropical forests of Mudumalai Wildlife Sanctuary, southern India, during 1998-2000 to manage the species effectively. Extensive survey of the three major habitats—tropical moist, dry deciduous and dry thorn—in the sanctuary shows that its distribution is continuous in moist and dry deciduous forests with good canopy contiguity and patchy along riverine areas in dry thorn and dry deciduous forests with sparse trees and broken canopy. Density estimates using 55 direct sightings from 199 km line transects show a mean of 2.9 (plus or minus 0.313 squirrels/km2. Daylight activity and feeding patterns assessed through 24,098 minutes of focal sampling reveal that animals feed and rest equal amounts of time. The diet constitutes seeds, bark, petioles, leaves and fruits from 25 plants, with Tectona grandis as the principal food source (41%. Its home range size varied from 0.8-1.7 ha with a mean of 1.3ha. Nesting characteristics assessed through 83 nests surveyed along 54km transects showed that the squirrel uses 15 of the 33 tree species found, with higher preference to Schleichera oleosa and Mangifera indica. Nest trees are significantly larger in height, gbh and canopy contiguity than nearest non-nest trees, which are attributed to better protection and escape from predators. Maintenance of diverse natural habitats and reduction in anthropogenic pressure are measures suggested for the conservation of giant squirrel populations in the study area.

  12. Performance analysis of deciduous morphology for detecting biological siblings.

    Science.gov (United States)

    Paul, Kathleen S; Stojanowski, Christopher M

    2015-08-01

    Family-centered burial practices influence cemetery structure and can represent social group composition in both modern and ancient contexts. In ancient sites dental phenotypic data are often used as proxies for underlying genotypes to identify potential biological relatives. Here, we test the performance of deciduous dental morphological traits for differentiating sibling pairs from unrelated individuals from the same population. We collected 46 deciduous morphological traits for 69 sibling pairs from the Burlington Growth Centre's long term Family Study. Deciduous crown features were recorded following published standards. After variable winnowing, inter-individual Euclidean distances were generated using 20 morphological traits. To determine whether sibling pairs are more phenotypically similar than expected by chance we used bootstrap resampling of distances to generate P values. Multidimensional scaling (MDS) plots were used to evaluate the degree of clustering among sibling pairs. Results indicate an average distance between siblings of 0.252, which is significantly less than 9,999 replicated averages of 69 resampled pseudo-distances generated from: 1) a sample of non-relative pairs (P < 0.001), and 2) a sample of relative and non-relative pairs (P < 0.001). MDS plots indicate moderate to strong clustering among siblings; families occupied 3.83% of the multidimensional space on average (versus 63.10% for the total sample). Deciduous crown morphology performed well in identifying related sibling pairs. However, there was considerable variation in the extent to which different families exhibited similarly low levels of phenotypic divergence. © 2015 Wiley Periodicals, Inc.

  13. Estimation of miniature forest parameters, species, tree shape, and distance between canopies by means of Monte-Carlo based radiative transfer model with forestry surface model

    International Nuclear Information System (INIS)

    Ding, Y.; Arai, K.

    2007-01-01

    A method for estimation of forest parameters, species, tree shape, distance between canopies by means of Monte-Carlo based radiative transfer model with forestry surface model is proposed. The model is verified through experiments with the miniature model of forest, tree array of relatively small size of trees. Two types of miniature trees, ellipse-looking and cone-looking canopy are examined in the experiments. It is found that the proposed model and experimental results show a coincidence so that the proposed method is validated. It is also found that estimation of tree shape, trunk tree distance as well as distinction between deciduous or coniferous trees can be done with the proposed model. Furthermore, influences due to multiple reflections between trees and interaction between trees and under-laying grass are clarified with the proposed method

  14. MORPHOLOGICAL RESEARCH ON FREE-RESIDUE OXIDATION PROCESSES IN CASES OF DECIDUAL CELLS OF PLACENTA IN CHORIOAMNIONOTIS AND BASAL DECIDUITIS COMBINED WITH IRON-DEFICIENCY ANEMIA IN THE PREGNANT

    Directory of Open Access Journals (Sweden)

    V. V. Ilika

    2017-07-01

    Full Text Available Background. The oxidative modification of proteins is lately pivotal to pathologists and it is a new way of research on different pathological conditions, as well as the diagnostics of inflammation processes in placenta. Objective. The study was aimed at the research of nitro peroxides and establishing the specific features of oxidative modification of proteins in inflammation of placenta with iron deficient anaemia in the pregnant. Methods. Сhemiluminescent and histochemical technique (with bromphenol blue on ‘acidic’ and ‘basic’ proteins according to Mikel Calvo was applied. Results. The intensity of nitro peroxides glow in chorioamnionitis and basal deciduitis increased in comparison with the samples of physiological and iron deficient anaemia gestation. At the same time in chorioamnionitis the glow intensity is higher than in basal deciduitis. Due to the results of immune histochemical technique held while analysing the samples, together with chorioamnionitis and basal deciduitis the R/B increases and in basal deciduitis the rate, is probably, higher, than in chorioamnionitis. At the same time, the extent of oxidative modification of proteins in cases of inflammation with iron deficient anaemia in the pregnant is on the average higher than with no iron deficient anaemia in the pregnant. Conclusions. High level of nitro peroxides in placentae basal plate in secundines inflammation, the increase in R/B rate, in other words the prevalence of ‘acidic’ proteins over ‘basic’ ones, is evidenced due to the increase of the intensity of oxidative modification processes of proteins in cases of deciduitis.

  15. Effects of tree species, water and nitrogen on mycorrhizal C flux

    Science.gov (United States)

    Menyailo, O.; Matvienko, A.

    2012-12-01

    Mycorrhiza plays an important role in global carbon cycle, especially, in forest soils, yet the effect of tree species on the amount and timing of C transfer through roots to myccorhiza is largely unknown. We studied the C transport to mycorrhiza under 6 most commonly dominant in boreal forests tree species using the mesh collars installed at the Siberian afforestation experiment. The CO2 flux from mycorrhizal and non-mycorrhizal mesh collars indicated the mycorrhizal C flux. Tree species strongly differed in C flux to mycorrhiza: more C was transferred by deciduous species than by conifers. The mycorrhizal CO2 flux was not linked to soil temperature but rather to trees phenology and to photosynthetic activity. All tree species transfered more carbon to mycorrhiza during the second half of summer and in September, this is because all the carbon photosynthesized earlier is used for building the tree biomass. Seasonal variation in C transfer to mycorrhiza was much larger than hourly variation (within a day). Nitrogen application (50 kg/ha) increased mycorrhizal C flux only under Scots pine, but not under larch, thus the effect of N application is tree species dependent. We found under most tree species that more C was transferred by trees to mycorrhiza in root-free collars, where the soil moisture was higher than in collars with roots. This suggests that trees preferentially support those parts of mycorrhiza, which can gain extra-resources.

  16. Comparative gene expression analysis of the human periodontal ligament in deciduous and permanent teeth.

    Directory of Open Access Journals (Sweden)

    Je Seon Song

    Full Text Available There are histological and functional differences between human deciduous and permanent periodontal ligament (PDL tissues. The aim of this study was to determine the differences between these two types of tissue at the molecular level by comparing their gene expression patterns. PDL samples were obtained from permanent premolars (n = 38 and anterior deciduous teeth (n = 31 extracted from 40 healthy persons. Comparative cDNA microarray analysis revealed several differences in gene expression between the deciduous and permanent PDL tissues. These findings were verified by qRT-PCR (quantitative reverse-transcription-polymerase chain reaction analysis, and the areas where genes are expressed were revealed by immunohistochemical staining. The expressions of 21 genes were up-regulated in deciduous relative to PDL tissues, and those of 30 genes were up-regulated in permanent relative to deciduous PDL tissues. The genes that were up-regulated in deciduous PDL tissues were those involved in the formation of the extracellular matrix (LAMC2, LAMB3, and COMP, tissue development (IGF2BP, MAB21L2, and PAX3, and inflammatory or immune reactions leading to tissue degradation (IL1A, CCL21, and CCL18. The up-regulated genes in permanent PDL tissues were related to tissue degradation (IL6 and ADAMTS18, myocontraction (PDE3B, CASQ2, and MYH10, and neurological responses (FOS, NCAM2, SYT1, SLC22A3, DOCK3, LRRTM1, LRRTM3, PRSS12, and ARPP21. The analysis of differential gene expressions between deciduous and permanent PDL tissues aids our understanding of histological and functional differences between them at the molecular level.

  17. Comparative gene expression analysis of the human periodontal ligament in deciduous and permanent teeth.

    Science.gov (United States)

    Song, Je Seon; Hwang, Dong Hwan; Kim, Seong-Oh; Jeon, Mijeong; Choi, Byung-Jai; Jung, Han-Sung; Moon, Seok Jun; Park, Wonse; Choi, Hyung-Jun

    2013-01-01

    There are histological and functional differences between human deciduous and permanent periodontal ligament (PDL) tissues. The aim of this study was to determine the differences between these two types of tissue at the molecular level by comparing their gene expression patterns. PDL samples were obtained from permanent premolars (n = 38) and anterior deciduous teeth (n = 31) extracted from 40 healthy persons. Comparative cDNA microarray analysis revealed several differences in gene expression between the deciduous and permanent PDL tissues. These findings were verified by qRT-PCR (quantitative reverse-transcription-polymerase chain reaction) analysis, and the areas where genes are expressed were revealed by immunohistochemical staining. The expressions of 21 genes were up-regulated in deciduous relative to PDL tissues, and those of 30 genes were up-regulated in permanent relative to deciduous PDL tissues. The genes that were up-regulated in deciduous PDL tissues were those involved in the formation of the extracellular matrix (LAMC2, LAMB3, and COMP), tissue development (IGF2BP, MAB21L2, and PAX3), and inflammatory or immune reactions leading to tissue degradation (IL1A, CCL21, and CCL18). The up-regulated genes in permanent PDL tissues were related to tissue degradation (IL6 and ADAMTS18), myocontraction (PDE3B, CASQ2, and MYH10), and neurological responses (FOS, NCAM2, SYT1, SLC22A3, DOCK3, LRRTM1, LRRTM3, PRSS12, and ARPP21). The analysis of differential gene expressions between deciduous and permanent PDL tissues aids our understanding of histological and functional differences between them at the molecular level.

  18. Distinctive genetic activity pattern of the human dental pulp between deciduous and permanent teeth.

    Directory of Open Access Journals (Sweden)

    Ji-Hee Kim

    Full Text Available Human deciduous and permanent teeth exhibit different developmental processes, morphologies, histological characteristics and life cycles. In addition, their pulp tissues react differently to external stimuli, such as the pulp sensitivity test, dental trauma and pulp therapy materials. These suggest differences in gene expression and regulation, and in this study we compared gene-expression profiles of the human dental pulp from deciduous and permanent teeth. Pulp tissues from permanent premolars and deciduous molars aged 11-14 years were extirpated and mRNA was isolated for cDNA microarray analysis, and quantitative real-time PCR (qPCR. Other teeth were used for immunohistochemical analysis (IHC. Microarray analysis identified 263 genes with a twofold or greater difference in expression level between the two types of pulp tissue, 43 and 220 of which were more abundant in deciduous and permanent pulp tissues, respectively. qPCR analysis was conducted for eight randomly selected genes, and the findings were consistent with the cDNA microarray results. IHC confirmed that insulin-like growth factor 2 mRNA-binding protein 1 (IGF2BP1 was broadly expressed in deciduous dental pulp tissue, but minimally expressed in permanent dental pulp tissue. Immunohistochemical analysis showed that calbindin 1 (CALB1, leucine-rich repeat-containing G-protein-coupled receptor 5 (LGR5, and gamma-aminobutyric acid A receptor beta 1 (GABRB1 were abundantly expressed in permanent predentin/odontoblasts, but only minimally expressed in deciduous dental pulp tissue. These results show that deciduous and permanent pulp tissues have different characteristics and gene expression, suggesting that they may have different functions and responses to therapies focused on pulp or dentin regeneration.

  19. Distinctive genetic activity pattern of the human dental pulp between deciduous and permanent teeth.

    Science.gov (United States)

    Kim, Ji-Hee; Jeon, Mijeong; Song, Je-Seon; Lee, Jae-Ho; Choi, Byung-Jai; Jung, Han-Sung; Moon, Seok Jun; DenBesten, Pamela K; Kim, Seong-Oh

    2014-01-01

    Human deciduous and permanent teeth exhibit different developmental processes, morphologies, histological characteristics and life cycles. In addition, their pulp tissues react differently to external stimuli, such as the pulp sensitivity test, dental trauma and pulp therapy materials. These suggest differences in gene expression and regulation, and in this study we compared gene-expression profiles of the human dental pulp from deciduous and permanent teeth. Pulp tissues from permanent premolars and deciduous molars aged 11-14 years were extirpated and mRNA was isolated for cDNA microarray analysis, and quantitative real-time PCR (qPCR). Other teeth were used for immunohistochemical analysis (IHC). Microarray analysis identified 263 genes with a twofold or greater difference in expression level between the two types of pulp tissue, 43 and 220 of which were more abundant in deciduous and permanent pulp tissues, respectively. qPCR analysis was conducted for eight randomly selected genes, and the findings were consistent with the cDNA microarray results. IHC confirmed that insulin-like growth factor 2 mRNA-binding protein 1 (IGF2BP1) was broadly expressed in deciduous dental pulp tissue, but minimally expressed in permanent dental pulp tissue. Immunohistochemical analysis showed that calbindin 1 (CALB1), leucine-rich repeat-containing G-protein-coupled receptor 5 (LGR5), and gamma-aminobutyric acid A receptor beta 1 (GABRB1) were abundantly expressed in permanent predentin/odontoblasts, but only minimally expressed in deciduous dental pulp tissue. These results show that deciduous and permanent pulp tissues have different characteristics and gene expression, suggesting that they may have different functions and responses to therapies focused on pulp or dentin regeneration.

  20. Immunochemical and ultrastructural assessment of the nature of the pericellular basement membrane of human decidual cells

    DEFF Research Database (Denmark)

    Wewer, U M; Faber, M; Liotta, L A

    1985-01-01

    Human decidual cells of early and late pregnancy were studied immunochemically and ultrastructurally with respect to the presence and nature of pericellular basement membrane material. The most prominent cell type in decidual tissue of both early and late pregnancy were large, mature epithelioid......-linked immunosorbent assay. Biosynthesis of laminin was shown by [35S]methionine labeling of short term organ cultures of decidual tissue followed by immunoprecipation, sodium dodecyl sulfate-polyacrylamide gel electrophoresis, and fluorography. The laminin chains migrated with the apparent molecular weights of 300...... and 200 kilodaltons under reducing conditions. Two other separate populations of cells were apparent in the decidual tissue of early pregnancy. A smaller group of rounded intermediate sized (15 to 25 micron) decidual cells had focal deposits basement membrane immunoreactive material scattered at the cell...

  1. Modified Willet′s appliance for bilateral loss of multiple deciduous molars: A case report

    OpenAIRE

    Dhindsa A; Pandit I

    2008-01-01

    No other factor plays a more significant role in preventive and interceptive dentistry than the preservation of deciduous dentition till its normal time of exfoliation. Premature loss of a deciduous tooth or a group of teeth might lead to wide range of implications. When the deciduous second molar is lost before the eruption of first permanent molar, intra-alveolar type of space maintainer is indicated. But in cases of bilateral loss of these teeth the conventional design generally poses a va...

  2. Modified Willet′s appliance for bilateral loss of multiple deciduous molars: A case report

    Directory of Open Access Journals (Sweden)

    Dhindsa A

    2008-09-01

    Full Text Available No other factor plays a more significant role in preventive and interceptive dentistry than the preservation of deciduous dentition till its normal time of exfoliation. Premature loss of a deciduous tooth or a group of teeth might lead to wide range of implications. When the deciduous second molar is lost before the eruption of first permanent molar, intra-alveolar type of space maintainer is indicated. But in cases of bilateral loss of these teeth the conventional design generally poses a variety of problems. Thus, the conventional designs are required to be modified according to the needs of the patient. Therefore, this paper describes an entirely new design of the Willet′s appliance in cases of bilateral loss of deciduous molars before the eruption of first permanent molar.

  3. Field note: irrigation of tree stands with groundwater containing 1,4-dioxane.

    Science.gov (United States)

    Ferro, Ari M; Tammi, Carl E

    2009-07-01

    Coniferous and deciduous tree stands totaling 14 ha were recently planted on a closed landfill, and when mature, the stands are expected to be part of a natural treatment system for recovered groundwater. The trees would be irrigated at the rate of 189 L/min year-round with water containing 1,4-dioxane (trees. The water is moderately saline and contains elevated levels of manganese. This paper describes a concurrent series of preliminary studies, performed prior to the full-scale planting, to assess the feasibility of the phytoremediation system. Greenhouse experiments were carried out to identify tree species that can take up 1,4-dioxane and are tolerant of the water. Estimates were made of the area of the tree stand necessary to transpire the irrigation water plus precipitation. The landfill matrix was characterized in terms of its percolation rate and water holding capacity and based on those results salinity-modeling studies were carried out to estimate the fate and leaching potential of the various inorganic species that would accumulate in the root-zone of the trees. A pilot study, currently in progress on the landfill, suggested that the landfill cap is a suitable matrix for the establishment of large trees, and that the stands could be irrigated without the production of excess drainage.

  4. Deciduous molar hypomineralization and molar incisor hypomineralization

    NARCIS (Netherlands)

    Elfrink, M.E.C.; ten Cate, J.M.; Jaddoe, V.W.V.; Hofman, A.; Moll, H.A.; Veerkamp, J.S.J.

    2012-01-01

    This study was embedded in the Generation R Study, a population-based prospective cohort study from fetal life until young adulthood. This study focused on the relationship between Deciduous Molar Hypomineralization (DMH) and Molar Incisor Hypomineralization (MIH). First permanent molars develop

  5. A preliminary study applying decision analysis to the treatment of caries in primary teeth.

    Science.gov (United States)

    Tamošiūnas, Vytautas; Kay, Elizabeth; Craven, Rebecca

    2013-01-01

    To determine an optimal treatment strategy for carious deciduous teeth. Manchester Dental Hospital. Decision analysis. The likelihoods of each of the sequelae of caries in deciduous teeth were determined from the literature. The utility of the outcomes from non-treatment and treatment was then measured in 100 parents of children with caries, using a visual analogue scale. Decision analysis was performed which weighted the value of each potential outcome by the probability of its occurrence. A decision tree "fold-back" and sensitivity analysis then determined which treatment strategies, under which circumstances, offered the maximum expected utilities. The decision to leave a carious deciduous tooth unrestored attracted a maximum utility of 76.65 and the overall expected utility for the decision "restore" was 73.27 The decision to restore or not restore carious deciduous teeth are therefore of almost equal value. The decision is however highly sensitive to the utility value assigned to the advent of pain by the patient. There is no clear advantage to be gained by restoring deciduous teeth if patients' evaluations of outcomes are taken into account. Avoidance of pain and avoidance of procedures which are viewed as unpleasant by parents should be key determinants of clinical decision making about carious deciduous teeth.

  6. Involvement of atypical transcription factor E2F8 in the polyploidization during mouse and human decidualization

    OpenAIRE

    Qi, Qian-Rong; Zhao, Xu-Yu; Zuo, Ru-Juan; Wang, Tong-Song; Gu, Xiao-Wei; Liu, Ji-Long; Yang, Zeng-Ming

    2015-01-01

    Polyploid decidual cells are specifically differentiated cells during mouse uterine decidualization. However, little is known about the regulatory mechanism and physiological significance of polyploidization in pregnancy. Here we report a novel role of E2F8 in the polyploidization of decidual cells in mice. E2F8 is highly expressed in decidual cells and regulated by progesterone through HB-EGF/EGFR/ERK/STAT3 signaling pathway. E2F8 transcriptionally suppresses CDK1, thus triggering the polypl...

  7. Observing Spring and Fall Phenology in a Deciduous Forest with Aerial Drone Imagery

    Directory of Open Access Journals (Sweden)

    Stephen Klosterman

    2017-12-01

    Full Text Available Plant phenology is a sensitive indicator of the effects of global change on terrestrial ecosystems and controls the timing of key ecosystem functions including photosynthesis and transpiration. Aerial drone imagery and photogrammetric techniques promise to advance the study of phenology by enabling the creation of distortion-free orthomosaics of plant canopies at the landscape scale, but with branch-level image resolution. The main goal of this study is to determine the leaf life cycle events corresponding to phenological metrics derived from automated analyses based on color indices calculated from drone imagery. For an oak-dominated, temperate deciduous forest in the northeastern USA, we find that plant area index (PAI correlates with a canopy greenness index during spring green-up, and a canopy redness index during autumn senescence. Additionally, greenness and redness metrics are significantly correlated with the timing of budburst and leaf expansion on individual trees in spring. However, we note that the specific color index for individual trees must be carefully chosen if new foliage in spring appears red, rather than green—which we observed for some oak trees. In autumn, both decreasing greenness and increasing redness correlate with leaf senescence. Maximum redness indicates the beginning of leaf fall, and the progression of leaf fall correlates with decreasing redness. We also find that cooler air temperature microclimates near a forest edge bordering a wetland advance the onset of senescence. These results demonstrate the use of drones for characterizing the organismic-level variability of phenology in a forested landscape and advance our understanding of which phenophase transitions correspond to color-based metrics derived from digital image analysis.

  8. Observing Spring and Fall Phenology in a Deciduous Forest with Aerial Drone Imagery.

    Science.gov (United States)

    Klosterman, Stephen; Richardson, Andrew D

    2017-12-08

    Plant phenology is a sensitive indicator of the effects of global change on terrestrial ecosystems and controls the timing of key ecosystem functions including photosynthesis and transpiration. Aerial drone imagery and photogrammetric techniques promise to advance the study of phenology by enabling the creation of distortion-free orthomosaics of plant canopies at the landscape scale, but with branch-level image resolution. The main goal of this study is to determine the leaf life cycle events corresponding to phenological metrics derived from automated analyses based on color indices calculated from drone imagery. For an oak-dominated, temperate deciduous forest in the northeastern USA, we find that plant area index (PAI) correlates with a canopy greenness index during spring green-up, and a canopy redness index during autumn senescence. Additionally, greenness and redness metrics are significantly correlated with the timing of budburst and leaf expansion on individual trees in spring. However, we note that the specific color index for individual trees must be carefully chosen if new foliage in spring appears red, rather than green-which we observed for some oak trees. In autumn, both decreasing greenness and increasing redness correlate with leaf senescence. Maximum redness indicates the beginning of leaf fall, and the progression of leaf fall correlates with decreasing redness. We also find that cooler air temperature microclimates near a forest edge bordering a wetland advance the onset of senescence. These results demonstrate the use of drones for characterizing the organismic-level variability of phenology in a forested landscape and advance our understanding of which phenophase transitions correspond to color-based metrics derived from digital image analysis.

  9. Distribution characteristics of mineral elements in tree Species from ...

    African Journals Online (AJOL)

    Tree species populations were 44 in Akyaakrom (AS), 29 in Dopiri (DS), and families were 18 in AS and 16 in DS. Tree densities were 121 and 99 in AS and DS, respectively, in 0.57 ha. In terms of tree species population, diversity and density, AS was superior to DS. The distribution of major mineral elements in the leaves ...

  10. Bioinspired leaves-on-branchlet hybrid carbon nanostructure for supercapacitors

    OpenAIRE

    Xiong, Guoping; He, Pingge; Lyu, Zhipeng; Chen, Tengfei; Huang, Boyun; Chen, Lei; Fisher, Timothy S.

    2018-01-01

    Designing electrodes in a highly ordered structure simultaneously with appropriate orientation, outstanding mechanical robustness, and high electrical conductivity to achieve excellent electrochemical performance remains a daunting challenge. Inspired by the phenomenon in nature that leaves significantly increase exposed tree surface area to absorb carbon dioxide (like ions) from the environments (like electrolyte) for photosynthesis, we report a design of micro-conduits in a bioinspired leav...

  11. Trees as methane sources: A case study of West Siberian South taiga

    Science.gov (United States)

    Churkina, A. I.; Mochenov, S. Yu; Sabrekov, S. F.; Glagolev, M. V.; Il’yasov, D. V.; Terentieva, I. E.; Maksyutov, S. S.

    2018-03-01

    Within this study, we were measuring methane emission from the tree trunks, leaves and branches in the seasonally flooded forest and in the forested bogs (pine-shrub-sphagnum ecosystems or “ryams”) in south taiga zone of Western Siberia. Our results suggest that the tree trunks may act as a methane conductor from the soil to the atmosphere bypassing the methanotrophically active zones of soil. The tree methane flux depends on a trunk diameter and an ecosystem type. The average methane emission from tree trunks was 0.0061±0.0003 mg CH4·m-2·h-1 per unit of ground area. The methane emission from branches and leaves was zero.

  12. Tree species traits cause divergence in soil acidification during four decades of postagricultural forest development

    DEFF Research Database (Denmark)

    Schrijver, An de; Frenne, Pieter de; Staelens, Jeroen

    2012-01-01

    -depth understanding of tree species-specific effects on soil acidification is therefore crucial, particularly in view of the predicted global increases in acidifying nitrogen (N) deposition. Here, we report soil acidification rates in a chronosequence of broadleaved deciduous forests planted on former arable land...... and unequivocally drives postagricultural forests towards more acidic conditions, but the rate of soil acidification is also determined by the tree species-specific leaf litter quality and litter decomposition rates. We propose that the intrinsic differences in leaf litter quality among tree species create...... fundamentally different nutrient cycles within the ecosystem, both directly through the chemical composition of the litter and indirectly through its effects on the size and composition of earthworm communities. Poor leaf litter quality contributes to the absence of a burrowing earthworm community, which...

  13. Decidualization and angiogenesis in early pregnancy: unravelling the functions of DC and NK cells.

    Science.gov (United States)

    Blois, Sandra M; Klapp, Burghard F; Barrientos, Gabriela

    2011-03-01

    Differentiation of endometrial stromal cells and formation of new maternal blood vessels at the time of embryo implantation are critical for the establishment and maintenance of gestation. The regulatory functions of decidual leukocytes during early pregnancy, particularly dendritic cells (DC) and NK cells, may be important not only for the generation of maternal immunological tolerance but also in the regulation of stromal cell differentiation and the vascular responses associated with the implantation process. However, the specific contributions of DC and NK cells during implantation are still difficult to dissect mainly due to reciprocal regulatory interactions established between them within the decidualizing microenvironment. The present review article discusses current evidence on the regulatory pathways driving decidualization in mice, suggesting that NK cells promote uterine vascular modifications that assist decidual growth but DC directly control stromal cell proliferation, angiogenesis and the homing and maturation of NK cell precursors in the pregnant uterus. Thus, successful implantation appears to result from an interplay between cellular components of the decidualizing endometrium involving immunoregulatory and pro-angiogenic functions of DC and NK cells. Copyright © 2010 Elsevier Ireland Ltd. All rights reserved.

  14. MORPHOLOGICAL ANALYSIS OF THE LEAVES OF Anacardium occidentale L.

    Directory of Open Access Journals (Sweden)

    Glenda Quaresma Ramos

    2016-03-01

    Full Text Available In morphological studies are analyzed various parameters, ranging from macro scale through the micro scale to the nanometer scale, which contribute to the study of taxonomy, pharmacognosy, ecology, among others. Among the structures found in plants, the leaves are most organs analyzed. This study aimed to analyze morphological features of the leaves of the cashew tree, which is a plant of great commercial importance in Brazil. In this work we observed sinuous epidermal cells in the adaxial and abaxial, characterize their stomata in paracytic surrounded subsidiaries cells. On the abaxial surface the presence of glandular trichomes was observed; and cross-sectional analysis showed a single-layered epidermis with compact mesophyll and several layers of parenchyma cells. Keywords: leaf anatomy; cashew tree; optical microscopy.

  15. Seasonal variations of trace element contents in leaves and bark of horse chestnut (Aesculus hippocastanum L. in urban and industrial regions in Serbia

    Directory of Open Access Journals (Sweden)

    Pavlović Marija

    2017-01-01

    Full Text Available In this study, we examined the ability of horse chestnut (Aesculus hippocastanum L. to capture heavy metals, and whether its capacity to absorb metals from soil is associated with surrounding ecological characteristics and sources of pollution. We studied the seasonal accumulation of B, Cu, Sr and Zn in leaves and bark, and the chlorophyll content in the common deciduous tree Aesculus hippocastanum L. in four urban parks in Pančevo, Smederevo, Obrenovac and Belgrade (Serbia affected by different anthropogenic activities. The research included plants from a control site located within the zone of a former oak forest. Our findings suggest that there are potential ecological risks around Smederevo, Belgrade and Obrenovac due to elevated concentrations of B and Zn relative to the average concentrations described for worldwide soils, as well as national regulations. Substantial and toxic foliar accumulation of B was observed in Smederevo and Belgrade, and of Sr in both plant tissues at all sites. However, the Cu and Zn contents in leaves were not enough to meet the physiological needs of plants. Chlorophyll a and the total carotenoid content peaked in August under the most unfavorable conditions of the year, which may be considered as an adaptive mechanism. The obtained results showed the remarkable complexity of environmental conditions and the difficulties A. hippocastanum, as a species, has to overcome. Under conditions of different types of urban and industrial pollution, A. hippocastanum showed great element accumulation potential and could be regarded as both an accumulator and a response indicator, since its leaves are quite susceptible to damage. [Project of the Serbian Ministry of Education, Science and Technological Development, Grant no. 173018

  16. Temple tree; Frangipani-common name; Gopur- champa - Sanskrit

    Indian Academy of Sciences (India)

    Plumeria rubraL. Syn. P. acutifoliaPoir. (Temple tree; Frangipani-common name; Gopur- champa - Sanskrit, Hindi) of Apocynaceae is an ornamental tree that is often cultivated in gardens and near temples. Both leaves and flowers are showy and contain milky latex. Flowers are in bunches, large and white with yellow ...

  17. Effects of graded levels of tannin-containing tropical tree leaves on in vitro rumen fermentation, total protozoa and methane production.

    Science.gov (United States)

    Bhatta, R; Saravanan, M; Baruah, L; Prasad, C S

    2015-03-01

    This study was carried out to determine the effect of graded levels of tannin-containing tropical tree leaves, Autocarpus integrifolis, Azardirachta indica and Ficus bengalensis, on the in vitro rumen fermentation pattern, total protozoa and methane suppression in order to establish the optimum dose of these leaves for inclusion in the ruminant diets. The air-dried and ground samples of Au. integrifolis, Az. indica and Ficus bengalensis were subjected to in vitro incubation using 30 ml buffered rumen fluid at 0, 2.5, 5.0, 10.0, 15.0, 20.0, 25.0 and 30.0% (dry matter refers to moisture-free basis) of a total mixed ration (TMR: refers to mixture of roughage and concentrate containing cereals and oil cakes) devoid of tannin. The TMR for the experimental incubation was prepared by mixing 40 parts of ground Elusine coracana straw as roughage source with 60 parts of concentrate mixture. The leaves contained an average 130 g kg(-1) CP with 7·0 MJ of ME kg(-1) DM. The average neutral detergent fibre (NDF) content was content also showed similar trend. However, condensed tannin (CT) was highest in F. bengalensis (260) followed by Au. integrifolis (186) and Az. indica (138). There was significant (P 5.0%) reduced TVFA concentration. Protozoa (cells per mL) were similar at all levels of inclusion with Au. integrifolis, but reduced in case of F. bengalensis and Az. indica. As the level of tannin increased in the incubation medium, there was a linear reduction in methane concentration. Highest methane reduction (%) was recorded in incubations supplemented with Az. indica (61.5) followed by F. bengalensis (46.8) and Au. integrifolis (30.3). It was established from this study that tropical leaves of F. bengalensis, Au. integrifolis and Az. indica suppress methanogenesis. Ficus bengalensis, Au. integrifolis and Az. indica leaves are of interest in the enteric methane ameliorative strategies. Total mixed ration containing 10-15% ground F. bengalensis or Au. integrifolis or Az

  18. Litter Controls Earthworm-Mediated Carbon and Nitrogen Transformations in Soil from Temperate Riparian Buffers

    OpenAIRE

    Maria Kernecker; Joann K. Whalen; Robert L. Bradley

    2014-01-01

    Nutrient cycling in riparian buffers is partly influenced by decomposition of crop, grass, and native tree species litter. Nonnative earthworms in riparian soils in southern Quebec are expected to speed the processes of litter decomposition and nitrogen (N) mineralization, increasing carbon (C) and N losses in gaseous forms or via leachate. A 5-month microcosm experiment evaluated the effect of Aporrectodea turgida on the decomposition of 3 litter types (deciduous leaves, reed canarygrass, an...

  19. Distribution and quantification of Candidatus Liberibacter americanus, agent of huanglongbing disease of citrus in São Paulo State, Brasil, in leaves of an affected sweet orange tree as determined by PCR.

    Science.gov (United States)

    Teixeira, Diva C; Saillard, Colette; Couture, Carole; Martins, Elaine C; Wulff, Nelson A; Eveillard-Jagoueix, Sandrine; Yamamoto, Pedro T; Ayres, Antonio J; Bové, Joseph M

    2008-06-01

    Huanglongbing (HLB), an insect-transmitted disease of citrus, known for many years in Asia and Africa, has appeared in the state of São Paulo State (SSP), Brazil, in 2004, and the state of Florida, USA, in 2005. HLB endangers the very existence of citrus, as trees infected with the bacterial pathogen, irrevocably decline. In the absence of curative procedures, control of HLB is difficult and only based on prevention. Even though not available in culture, the HLB bacterium could be shown to be Gram-negative and to represent a new candidate genus, Candidatus Liberibacter, in the alpha subdivision of the Proteobacteria. Three Candidatus (Ca.) L. species occur: Ca. L. africanus in Africa, Ca. L. asiaticus in Asia, SSP, and Florida, and Ca. L. americanus in SSP. The liberibacters occur exclusively in the phloem sieve tubes. On affected trees, HLB symptoms are often seen on certain branches only, suggesting an uneven distribution of the Liberibacter. Occurrence of Ca. L. americanus, the major HLB agent in SSP, has been examined in 822 leaf samples from an affected sweet orange tree by two conventional PCR techniques and a newly developed real time (RTi) PCR, also used for quantification of the Liberibacter in the leaves. Even though RTi-PCR was able to detect as few as 10 liberibacters per gram of leaf tissue (l/g), no liberibacters could be detected in any of the many leaf samples from a symptomless branch, while in blotchy mottle leaves from symptomatic branches of the same tree, the Liberibacter titer reached values as high as 10(7)l/g. These results demonstrate the uneven distribution of the Liberibacter in HLB-affected trees.

  20. Effect of Tree Phenology on LiDAR Measurement of Mediterranean Forest Structure

    Directory of Open Access Journals (Sweden)

    William Simonson

    2018-04-01

    Full Text Available Retrieval of forest biophysical properties using airborne LiDAR is known to differ between leaf-on and leaf-off states of deciduous trees, but much less is understood about the within-season effects of leafing phenology. Here, we compare two LiDAR surveys separated by just six weeks in spring, in order to assess whether LiDAR variables were influenced by canopy changes in Mediterranean mixed-oak woodlands at this time of year. Maximum and, to a slightly lesser extent, mean heights were consistently measured, whether for the evergreen cork oak (Quercus suber or semi-deciduous Algerian oak (Q. canariensis woodlands. Estimates of the standard deviation and skewness of height differed more strongly, especially for Algerian oaks which experienced considerable leaf expansion in the time period covered. Our demonstration of which variables are more or less affected by spring-time leafing phenology has important implications for analyses of both canopy and sub-canopy vegetation layers from LiDAR surveys.

  1. Distribution of total nitrogen and N-15 labelled nitrogen applied to apple trees

    International Nuclear Information System (INIS)

    Calvache, Marcelo.

    1990-01-01

    The efficiency of nitrogen fertilization from one year's application was studied in apple trees. Urea enriched with 1,5% N-15 a.e. was applied to 2 years old apple trees. Two irrigation treatments were studied, Al approx. 200mm/week and A2 approx. 100 mm/week. The distribution of N in the different parts of the trees was determined after 2 months of fertilization and after the experimental trees were excavated. The recovery of labelled fertilizer N was different in the trees in both treatments (Al = 1,2% and A2 = 3,1%). However, the distribution in the tree's parts was similar: 46% in leaves, 34% in branches and 20% in roots. We also determined that sampling only 20% of leaves at the beginning and the end of the experiment it is possible to know the quantity of nitrogen from fertilizer, without the excavation trees

  2. The influence of vegetation on the horizontal and vertical distribution of pollutants in a street canyon.

    Science.gov (United States)

    Salmond, J A; Williams, D E; Laing, G; Kingham, S; Dirks, K; Longley, I; Henshaw, G S

    2013-01-15

    Space constraints in cities mean that there are only limited opportunities for increasing tree density within existing urban fabric and it is unclear whether the net effect of increased vegetation in street canyons is beneficial or detrimental to urban air quality at local scales. This paper presents data from a field study undertaken in Auckland, New Zealand designed to determine the local impact of a deciduous tree canopy on the distribution of the oxides of nitrogen within a street canyon. The results showed that the presence of leaves on the trees had a marked impact on the transport of pollutants and led to a net accumulation of pollutants in the canyon below the tree tops. The incidence and magnitude of temporally localised spikes in pollutant concentration were reduced within the tree canopy itself. A significant difference in pollutant concentrations with height was not observed when leaves were absent. Analysis of the trends in concentration associated with different wind directions showed a smaller difference between windward and leeward sides when leaves were on the trees. A small relative increase in concentrations on the leeward side was observed during leaf-on relative to leaf-off conditions as predicted by previous modelling studies. However the expected reduction in concentrations on the windward side was not observed. The results suggest that the presence of leaves on the trees reduces the upwards transport of fresh vehicle emissions, increases the storage of pollutants within the canopy space and reduces the penetration of clean air downwards from aloft. Differences observed between NO and NO(2) concentrations could not be accounted for by dispersion processes alone, suggesting that there may also be some changes in the chemistry of the atmosphere associated with the presence of leaves on the trees. Copyright © 2012 Elsevier B.V. All rights reserved.

  3. Water metabolism of leaves of Quercus robur in antierosion stands in the south of its range

    Directory of Open Access Journals (Sweden)

    V. P. Bessonova

    2016-10-01

    Full Text Available We have investigated the main parameters of water exchange in leaves of Quercus robur L. which grow on the south-facing slope of the Viyskoviy ravine in a variety of water supply conditions. We established that the greatest intensity of transpiration of leaves of Q. robur occurred in the forest vegetation conditions of SG2, the smallest in SG1–0. In all study periods the largest amplitude of daily fluctuations in intensity of transpiration occurred in leaves of plants along the talweg, at other test sites the limits were much lower. The highest rates of transpiration were in September, which is connected with the high temperatures and lower relative air humidity compared with the days of measurement in July and May. We established that at the beginning of the growing season there was no difference in the total amount of water in the leaves of the trees that grow on the middle and upper parts of the slope, but that it was greater in plants along the talweg. In the following months the difference between the water content in the leaves of trees along the talweg and upper third of the slope increased. The leaves of trees that grow in the poorest conditions of water supply were characterized by the highest water-holding capacity, which is coordinated with their containing the highest content of hydrophilic colloids. The values for water deficit in May and in July fell within the maximum fluctuations for the species studied, but in early September they exceeded the maximum value in the leaves of trees on the upper third of the slope.

  4. Least Squares Methods for Equidistant Tree Reconstruction

    OpenAIRE

    Fahey, Conor; Hosten, Serkan; Krieger, Nathan; Timpe, Leslie

    2008-01-01

    UPGMA is a heuristic method identifying the least squares equidistant phylogenetic tree given empirical distance data among $n$ taxa. We study this classic algorithm using the geometry of the space of all equidistant trees with $n$ leaves, also known as the Bergman complex of the graphical matroid for the complete graph $K_n$. We show that UPGMA performs an orthogonal projection of the data onto a maximal cell of the Bergman complex. We also show that the equidistant tree with the least (Eucl...

  5. Encoding phylogenetic trees in terms of weighted quartets.

    Science.gov (United States)

    Grünewald, Stefan; Huber, Katharina T; Moulton, Vincent; Semple, Charles

    2008-04-01

    One of the main problems in phylogenetics is to develop systematic methods for constructing evolutionary or phylogenetic trees. For a set of species X, an edge-weighted phylogenetic X-tree or phylogenetic tree is a (graph theoretical) tree with leaf set X and no degree 2 vertices, together with a map assigning a non-negative length to each edge of the tree. Within phylogenetics, several methods have been proposed for constructing such trees that work by trying to piece together quartet trees on X, i.e. phylogenetic trees each having four leaves in X. Hence, it is of interest to characterise when a collection of quartet trees corresponds to a (unique) phylogenetic tree. Recently, Dress and Erdös provided such a characterisation for binary phylogenetic trees, that is, phylogenetic trees all of whose internal vertices have degree 3. Here we provide a new characterisation for arbitrary phylogenetic trees.

  6. Relationship of Climatic and Forest Factors to Drought- and Heat-Induced Tree Mortality.

    Directory of Open Access Journals (Sweden)

    Qingyin Zhang

    Full Text Available Tree mortality due to warming and drought is a critical aspect of forest ecosystem in responding to climate change. Spatial patterns of tree mortality induced by drought and its influencing factors, however, have yet to be documented at the global scale. We collected observations from 248 sites globally where trees have died due to drought and then assessed the effects of climatic and forest factors on the rate of tree mortality. The global mean annual mortality rate was 5.5%. The rate of tree mortality was significantly and negatively correlated with mean annual precipitation (P 2000 mm and was severe in regions with mean annual precipitation <1000 mm. Mortality rates varied amongst species. The global annual rate of mortality was much higher for gymnosperms (7.1% than angiosperms (4.8% but did not differ significantly between evergreen (6.2% and deciduous (6.1% species. Stand age and wood density affected the mortality rate. Saplings (4.6% had a higher mortality rate than mature trees (3.2%, and mortality rates significantly decreased with increasing wood density for all species (P < 0.01. We therefore concluded that the tree mortality around the globe varied with climatic and forest factors. The differences between tree species, wood density, stand density, and stand age should be considered when evaluating tree mortality at a large spatial scale during future climatic extremes.

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

    International Nuclear Information System (INIS)

    Khavaninzadeh, Ali Reza; Veroustraete, Frank; Van Wittenberghe, Shari; Verrelst, Jochem; Samson, Roeland

    2015-01-01

    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

  8. Radionuclides in a deciduous forest surrounding a shallow-land-burial site in the eastern United States

    International Nuclear Information System (INIS)

    Rickard, W.H.; Kirby, L.J.; McShane, M.C.

    1981-06-01

    The objective of this study was to determine if radioactive materials buried in trenches at the Maxey Flats burial ground in eastern Kentucky have migrated into the surrounding oak-hickory forest. Forest floor litter, minearl soil, and tree leaves were sampled and the radionuclide content measured

  9. Watch out for the leaves!

    CERN Multimedia

    HSE Unit

    2013-01-01

    Now that autumn is here, dead leaves falling from the trees form a colourful carpet that is pleasing to the eye. However, the reality is less pleasant for pedestrians, since these leaves increase the risk of slipping and falling, especially when the ground is wet.   These conditions are also hazardous for two- and four-wheeled vehicles, whose grip on the ground can be severely reduced, thereby increasing the risk of them skidding out of control. Cyclists are among the most vulnerable road users when faced with these hazards. It is therefore essential to be alert to the dangers, which can be lessened by taking a few simple precautions such as moderating your speed and wearing suitable shoes. We also invite you to notify the Service Desk if you notice a road or pavement where there is a high concentration of dead leaves. The CERN Roads and Drainage Service will then ensure that the leaves are cleared in order to reduce the risk of accidents in the area.

  10. In vitro evaluation of fluoride products in the development of carious lesions in deciduous teeth.

    Science.gov (United States)

    Santos, Lucineide de Melo; Reis, José Ivo Limeira dos; Medeiros, Maria Perolina de; Ramos, Sheyla Moreira; Araújo, Juliane Mendes de

    2009-01-01

    The purpose of this study was to evaluate the effect of the application of fluoride products on the development of enamel caries in deciduous teeth. A total of 108 deciduous teeth were chosen for the study. Acid-resistant varnish was applied on the teeth, leaving only one area of 5 mm x 1 mm of dental enamel exposed. The teeth were allocated randomly to one of the following groups: 1) control - toothpaste without fluoride; 2) 1.23% fluoride gel; 3) Duraflur fluoride varnish; 4) Duraphat fluoride varnish; 5) Fluorniz fluoride varnish; 6) Fluorphat fluoride varnish; 7) varnish with Duofluorid; 8) 12% silver fluoride diamine (Cariestop); 9) children's fluoride toothpaste (500 ppm). The tested products were applied on the teeth according to the manufacturer's recommendations and the teeth were stored in a moist environment for 24 hours. Each group of teeth was then subjected to a pH cycling model for 14 days, after which the teeth were cut through the center for an analysis of the depth of the carious lesion by polarized light microscopy. Comparisons were made between the treatments and the control group. The mean lesion depth values were 318 microm +/- 39 (control), 213 microm +/- 27 (fluoride gel), 203 microm +/- 34 (Duraflur), 133 microm +/- 25 (Duraphat), 207 microm +/- 27 (Fluor-niz), 212 microm +/- 27 (Fluorphat), 210 +/- 28 (Duofluorid), 146 +/- 31 (Cariestop) and 228 +/- 24 (fluoride toothpaste). None of the products used here was able to completely prevent the formation of lesions. The highest cariostatic effect was achieved by fluoride varnish Duraphat and the lowest by the fluoride toothpaste.

  11. Rapid and Pervasive Occupation of Fallen Mangrove Leaves by a Marine Zoosporic Fungus †

    OpenAIRE

    Newell, S. Y.; Miller, J. D.; Fell, J. W.

    1987-01-01

    Samples of leaves of red mangrove (Rhizophora mangle) were incubated on an agar medium selective for pythiaceous oomycetes. Leaves on trees above the water did not contain oomycetes. Marine oomycetes, principally Phytophthora vesicula, had colonized leaves within 2 h of leaf submergence, probably finding them by chemotaxis. The frequency of occurrence of P. vesicula in submerged leaves reached 100% within 30 h of submergence. By 43 h most, if not all, parts of leaves were occupied, and surfac...

  12. Eco-physiological adaptation of dominant tree species at two contrasting karst habitats in southwestern China [v1; ref status: indexed, http://f1000r.es/xt

    Directory of Open Access Journals (Sweden)

    Shouren Zhang

    2013-05-01

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

  13. Nitrogen Nutrition of Fruit Trees to Reconcile Productivity and Environmental Concerns.

    Science.gov (United States)

    Carranca, Corina; Brunetto, Gustavo; Tagliavini, Massimo

    2018-01-10

    Although perennial fruit crops represent 1% of global agricultural land, they are of a great economic importance in world trade and in the economy of many regions. The perennial woody nature of fruit trees, their physiological stages of growth, the root distribution pattern, and the presence of herbaceous vegetation in alleys make orchard systems efficient in the use and recycling of nitrogen (N). The present paper intends to review the existing literature on N nutrition of young and mature deciduous and evergreen fruit trees with special emphasis to temperate and Mediterranean climates. There are two major sources of N contributing to vegetative tree growth and reproduction: root N uptake and internal N cycling. Optimisation of the use of external and internal N sources is important for a sustainable fruit production, as N use efficiency by young and mature fruit trees is generally lower than 55% and losses of fertilizer N may occur with the consequent economic and environmental concern. Organic alternatives to mineral N fertilizer like the application of manure, compost, mulching, and cover crops are scarcely used in perennial fruit trees, in spite of the fact that society's expectations call for more sustainable production techniques and the demand for organic fruits is increasing.

  14. Sapwood Area Related to Tree Size, Tree Age, and Leaf Area Index in Cedrus libani

    OpenAIRE

    Güney, Aylin

    2018-01-01

    Sapwoodincludes the water conducting part of the stem which transports water andminerals from roots to leaves. Studies using sap flow gauges have to determinethe area of the sapwood in order to scale measured sap flow densities to thetree or stand level. The aim of this study was to investigate the relationshipbetween sapwood area at breast height and other tree parameters which are easyto measure of the montane Mediterranean conifer Cedrus libani, including a total number of 92 study trees o...

  15. Biology and distribution of chafers (Coleoptera, Scarabaeidae) living in hollow trees in Sweden.

    OpenAIRE

    Nilsson, Sven; Baranowski, Rickard; Hedin, Jonas; Jansson, Niklas; Ranius, Thomas

    2002-01-01

    We review the ecology and distributions of the chafers Liocola marmorata (F.), Gnorimus nobilis (L.) and Gnorimus variabilis (L.) in Sweden based on museum and several large private collections. These species live in hollow deciduous trees, in Sweden especially in oaks. The former and recently documented localities are shown on maps. More than 100 years ago, all the species as well as their habitats were more common in Sweden than today. One problem when interpreting old finds is that hollow ...

  16. The stopping rules for winsorized tree

    Science.gov (United States)

    Ch'ng, Chee Keong; Mahat, Nor Idayu

    2017-11-01

    Winsorized tree is a modified tree-based classifier that is able to investigate and to handle all outliers in all nodes along the process of constructing the tree. It overcomes the tedious process of constructing a classical tree where the splitting of branches and pruning go concurrently so that the constructed tree would not grow bushy. This mechanism is controlled by the proposed algorithm. In winsorized tree, data are screened for identifying outlier. If outlier is detected, the value is neutralized using winsorize approach. Both outlier identification and value neutralization are executed recursively in every node until predetermined stopping criterion is met. The aim of this paper is to search for significant stopping criterion to stop the tree from further splitting before overfitting. The result obtained from the conducted experiment on pima indian dataset proved that the node could produce the final successor nodes (leaves) when it has achieved the range of 70% in information gain.

  17. Terral De Vicuna, a Foehnlike Wind in Semiarid Northern Chile: Meteorological Aspects and Implications for the Fulfillment of Chill Requirements in Deciduous Fruit Trees

    Science.gov (United States)

    Montes, Carlo; Rutllant, Jose A.; Aguirre, Anita; Bascunan-Godoy, Luisa; Julia, Cristobal

    2016-01-01

    The terral de Vicuña is a warm and dry wind that flows down the Elqui Valley in north-central Chile typically at dawn and early morning. Given that most terral episodes occur in austral winter when chill accumulation by deciduous fruit trees proceeds, negative effects on agriculture may be expected. During 11 (2004-14) winters a meteorological characterization of terral winds and the assessment of their impact on chill accumulation, by the modified Utah Model and the Dynamic Model, were performed. Within this period, 67 terral days (TD) were identified as those in which nighttime to early morning wind direction and speed, air temperature, and relative humidity reached defined thresholds on an hourly basis (terral hours). Most frequent TD featured 6-9 consecutive terral hours; duration is considered here as a proxy for their intensity. Synoptic-scale meteorological analysis shows that 65% of moderate and strong terral events develop as a cold, migratory anticyclone drifts poleward of the study area, coinciding with the onset of a midtropospheric ridge over central Chile, bringing southwest winds on top of the Andes (approximately 500-hPa level). The remaining 35% are either associated with 500-hPa easterlies (foehn like), with prefrontal conditions ahead of a trough driving northwest 500-hPa winds, or with transitional 500-hPa westerlies.Assessments of chill accumulation during TD show that, although present average and cold winter conditions do not represent a major TD hazard to local agriculture, lower chill accumulation associated with anomalously high nocturnal temperatures could be significantly more important during present and future warmer winters.

  18. Modeling the temporal dynamics of nonstructural carbohydrate pools in forest trees

    Energy Technology Data Exchange (ETDEWEB)

    Richardson, Andrew [Northern Arizona Univ., Flagstaff, AZ (United States); Harvard Univ., Cambridge, MA (United States)

    2017-11-09

    Trees store carbohydrates, in the form of sugars and starch, as reserves to be used to power both future growth as well as to support day-to-day metabolic functions. These reserves are particularly important in the context of how trees cope with disturbance and stress—for example, as related to pest outbreaks, wind or ice damage, and extreme climate events. In this project, we measured the size of carbon reserves in forest trees, and determined how quickly these reserves are used and replaced—i.e., their “turnover time”. Our work was conducted at Harvard Forest, a temperate deciduous forest in central Massachusetts. Through field sampling, laboratory-based chemical analyses, and allometric modeling, we scaled these measurements up to whole-tree NSC budgets. We used these data to test and improve computer simulation models of carbon flow through forest ecosystems. Our modeling focused on the mathematical representation of these stored carbon reserves, and we examined the sensitivity of model performance to different model structures. This project contributes to DOE’s goal to improve next-generation models of the earth system, and to understand the impacts of climate change on terrestrial ecosystems.

  19. CLIMATE-TREE GROWTH RELATIONSHIPS OF Mimosa tenuiflora IN SEASONALLY DRY TROPICAL FOREST, BRAZIL

    Directory of Open Access Journals (Sweden)

    Patrícia Póvoa Mattos

    2015-03-01

    Full Text Available Mimosa tenuiflora is a native pioneer tree from the Caatinga used commercially as firewood due to its high calorific value. It is deciduous, its trunk does not reach large diameters and it has good regrowth capacity. This study intended to determine the annual increment in diameter of M. tenuiflora and its correlation with rainfall, as basis for fuel wood management. Disks from the stem base of M. tenuiflora trees were collected in 2008 in Sertânia and Serra Talhada, Pernambuco State, from regrowth of trees coppiced in 2003 and in Limoeiro do Norte, Ceará State, from a plantation established in 2002. The trees have well-defined annual growth rings, highly correlated with annual precipitation and are well-suited for dendrochronological investigations. Forest managers must consider the influence of previous drier years in the wood production when predicting fuel wood harvesting. The high growth correlation with the previous year’s rainfall in regions where the rains start after photoperiodic stimulation indicate the necessity of understanding the growth dynamics of the species under dry forest conditions through additional ecophysiology studies.

  20. 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. Crown Copyright © 2015. Published by Elsevier Ltd. All rights reserved.

  1. Nitrogenous compounds, phenolic compounds and morphological aspects of leaves: comparison of deciduous and semideciduous arboreal legumes Compostos nitrogenados, fenólicos e aspecto morfológico em folhas: comparação entre leguminosas arbóreas semidecíduas e decíduas

    Directory of Open Access Journals (Sweden)

    Ana Lúcia da Silva Lima

    2006-02-01

    Full Text Available In general, perennial species contain higher concentrations of certain secondary compounds, such as phenolics, lower levels of nitrogenous compounds, and greater specific leaf mass (SLM than deciduous species. The aim of this study was to verify whether the comparative data reported in the literature regarding deciduous and evergreen species, also applies to four selected species of a semideciduous tropical forest (a remnant of the Atlantic Forest. The four species chosen for this study, each with apparently different leaf life spans, were two semideciduous (Hymenaea courbaril L. var. stilbocarpa (Hayne Lee et Lang., and Lonchocarpus guilleminianus (Tul. Malme, and two deciduous (Enterolobium contortisiliquum (Vell. Morong., and Peltophorum dubium (Spreng. Taub.. Plants were grown in a greenhouse in plastic pots containing soil taken from their natural habitat. Mature leaves were harvested for determination of the SLM and contents of phenolic compounds, tannins, nitrate, protein, free amino acids, chlorophyll, and nitrogen. Data registered are in agreement with those of the literature. Leaves with the longest life span had the highest content of phenolics and the lowest levels of tannins, nitrate, protein, amino acids, chlorophyll and nitrogen, as well as presenting the greatest SLM.Em geral as espécies perenifólias possuem maior concentração de alguns compostos secundários, como por exemplo fenóis, menor concentração de compostos nitrogenados e maior massa foliar específica (MFE, quando comparadas a espécies decíduas. O objetivo deste trabalho foi verificar se as observações encontradas na literatura, comparando espécies perenifólias e decíduas aplicam-se também a quatro espécies de uma mata semidecídua, remanescente da Mata Atlântica. Das quatro espécies usadas neste estudo, que aparentemente apresentavam longevidades foliares diferentes, duas eram semidecíduas (Hymenaea courbaril L. var. stilbocarpa (Hayne Lee et Lang. e

  2. Using fragmentation trees and mass spectral trees for identifying unknown compounds in metabolomics.

    Science.gov (United States)

    Vaniya, Arpana; Fiehn, Oliver

    2015-06-01

    Identification of unknown metabolites is the bottleneck in advancing metabolomics, leaving interpretation of metabolomics results ambiguous. The chemical diversity of metabolism is vast, making structure identification arduous and time consuming. Currently, comprehensive analysis of mass spectra in metabolomics is limited to library matching, but tandem mass spectral libraries are small compared to the large number of compounds found in the biosphere, including xenobiotics. Resolving this bottleneck requires richer data acquisition and better computational tools. Multi-stage mass spectrometry (MSn) trees show promise to aid in this regard. Fragmentation trees explore the fragmentation process, generate fragmentation rules and aid in sub-structure identification, while mass spectral trees delineate the dependencies in multi-stage MS of collision-induced dissociations. This review covers advancements over the past 10 years as a tool for metabolite identification, including algorithms, software and databases used to build and to implement fragmentation trees and mass spectral annotations.

  3. Biomass production and essential oil yield from leaves, fine stems and resprouts using pruning the crown of Aniba canelilla (H.B.K.) (Lauraceae) in the Central Amazon

    OpenAIRE

    Manhães,Adriana Pellegrini; Veiga-Júnior,Valdir Florêncio da; Wiedemann,Larissa Silveira Moreira; Fernandes,Karenn Silveira; Sampaio,Paulo de Tarso Barbosa

    2012-01-01

    Aniba canelilla (H.B.K.) Mez. is a tree species from Amazon that produces essential oil. The oil extraction from its leaves and stems can be an alternative way to avoid the tree cutting for production of essential oil. The aim of this study was to analyse factors that may influence the essential oil production and the biomass of resprouts after pruning the leaves and stems of A. canelilla trees. The tree crowns were pruned in the wet season and after nine months the leaves and stems of the re...

  4. Adsorption of heavy metal ions by sawdust of deciduous trees

    International Nuclear Information System (INIS)

    Bozic, D.; Stankovic, V.; Gorgievski, M.; Bogdanovic, G.; Kovacevic, R.

    2009-01-01

    The adsorption of heavy metal ions from synthetic solutions was performed using sawdust of beech, linden and poplar trees. The adsorption depends on the process time, pH of the solution, type of ions, initial concentration of metals and the sawdust concentration in suspension. The kinetics of adsorption was relatively fast, reaching equilibrium for less than 20 min. The adsorption equilibrium follows Langmuir adsorption model. The ion exchange mechanism was confirmed assuming that the alkali-earth metals from the adsorbent are substituted by heavy metal ions and protons. On lowering the initial pH, the adsorption capacity decreased, achieving a zero value at a pH close to unity. The maximum adsorption capacity (7-8 mg g -1 of sawdust) was achieved at a pH between 3.5 and 5 for all the studied kinds of sawdust. The initial concentration of the adsorbate and the concentration of sawdust strongly affect the process. No influence of particles size was evidenced. A degree of adsorption higher than 80% can be achieved for Cu 2+ ions but it is very low for Fe 2+ ions, not exceeding 10%.

  5. Decidual Stromal Cell Response to Paracrine Signals from the Trophoblast: Amplification of Immune and Angiogenic Modulators

    DEFF Research Database (Denmark)

    Hess, AP; Hamilton, AE; Talbi, S

    2007-01-01

    During the invasive phase of implantation, trophoblasts and maternal decidual stromal cells secrete products that regulate trophoblast differentiation and migration into the maternal endometrium. Paracrine interactions between the extravillous trophoblast and the maternal decidua are important...... a functional genomics approach to investigate these paracrine interactions. Human endometrial stromal cells were decidualized with progesterone and were further treated with conditioned media (CM) from human trophoblasts (TCM) or, as a control, with conditioned media (CCM) from non-decidualized stromal cells...... regulated groups. The data demonstrate a significant induction of pro-inflammatory cytokines and chemokines, as well as angiogenic/static factors in decidualized endometrial stromal cells in response to trophoblast-secreted products. The data suggest that the trophoblast acts to alter the local immune...

  6. The Potential of EnMAP and Sentinel-2 Data for Detecting Drought Stress Phenomena in Deciduous Forest Communities

    Directory of Open Access Journals (Sweden)

    Sandra Dotzler

    2015-10-01

    Full Text Available Given the importance of forest ecosystems, the availability of reliable, spatially explicit information about the site-specific climate sensitivity of tree species is essential for implementing suitable adaptation strategies. In this study, airborne hyperspectral data were used to assess the response of deciduous species (dominated by European beech and Sessile and Pedunculate oak to water stress during a summery dry spell. After masking canopy gaps, shaded crown areas and non-deciduous species, potentially indicative spectral indices, the Photochemical Reflectance Index (PRI, Moisture Stress Index (MSI, Normalized Difference Water Index (NDWI, and Chlorophyll Index (CI, were analyzed with respect to available maps of site-specific soil moisture regimes. PRI provided an important indication of site-specific photosynthetic stress on leaf level in relation to limitations in soil water availability. The CI, MSI and NDWI revealed statistically significant differences in total chlorophyll and water concentration at the canopy level. However, after reducing the canopy effects by normalizing these indices with respect to the structure-sensitive simple ratio (SR vegetation index, it was not yet possible to identify site-specific concentration differences in leaf level at this early stage of the drought. The selected indicators were also tested with simulated EnMAP and Sentinel-2 data (derived from the original airborne data set. While PRI proved to be useful also in the spatial resolution of EnMAP (GSD = 30 m, this was not the case with Sentinel-2, owing to the lack of adequate spectral bands; the remaining indicators (MSI, CI, SR were also successfully produced with Sentinel-2 data at superior spatial resolution (GSD = 10 m. The study confirms the importance of using earth observation systems for supplementing traditional ecological site classification maps, particularly during dry spells and heat waves when ecological gradients are increasingly

  7. TreeRipper web application: towards a fully automated optical tree recognition software

    Directory of Open Access Journals (Sweden)

    Hughes Joseph

    2011-05-01

    Full Text Available Abstract Background Relationships between species, genes and genomes have been printed as trees for over a century. Whilst this may have been the best format for exchanging and sharing phylogenetic hypotheses during the 20th century, the worldwide web now provides faster and automated ways of transferring and sharing phylogenetic knowledge. However, novel software is needed to defrost these published phylogenies for the 21st century. Results TreeRipper is a simple website for the fully-automated recognition of multifurcating phylogenetic trees (http://linnaeus.zoology.gla.ac.uk/~jhughes/treeripper/. The program accepts a range of input image formats (PNG, JPG/JPEG or GIF. The underlying command line c++ program follows a number of cleaning steps to detect lines, remove node labels, patch-up broken lines and corners and detect line edges. The edge contour is then determined to detect the branch length, tip label positions and the topology of the tree. Optical Character Recognition (OCR is used to convert the tip labels into text with the freely available tesseract-ocr software. 32% of images meeting the prerequisites for TreeRipper were successfully recognised, the largest tree had 115 leaves. Conclusions Despite the diversity of ways phylogenies have been illustrated making the design of a fully automated tree recognition software difficult, TreeRipper is a step towards automating the digitization of past phylogenies. We also provide a dataset of 100 tree images and associated tree files for training and/or benchmarking future software. TreeRipper is an open source project licensed under the GNU General Public Licence v3.

  8. Should deciduous teeth be preserved in adult patients? How about stem cells? Is it reasonable to preserve them?

    Directory of Open Access Journals (Sweden)

    Alberto Consolaro

    2016-04-01

    Full Text Available Abstract When seeking orthodontic treatment, many adolescents and adult patients present with deciduous teeth. Naturally, deciduous teeth will inevitably undergo exfoliation at the expected time or at a later time. Apoptosis is the biological trigger of root resorption. In adult patients, deciduous teeth should not be preserved, as they promote: infraocclusion, traumatic occlusion, occlusal trauma, diastemata and size as well as morphology discrepancy malocclusion. Orthodontic movement speeds root resorption up, and so do restoring or recontouring deciduous teeth in order to establish esthetics and function. Deciduous teeth cells are dying as a result of apoptosis, and their regeneration potential, which allows them to act as stem cells, is limited. On the contrary, adult teeth cells have a greater proliferative potential. All kinds of stem cell therapies are laboratory investigative non authorized trials.

  9. The Endocannabinoid System in the Postimplantation Period: A Role during Decidualization and Placentation

    Directory of Open Access Journals (Sweden)

    B. M. Fonseca

    2013-01-01

    Full Text Available Although the detrimental effects of cannabis consumption during gestation are known for years, the vast majority of studies established a link between cannabis consumption and foetal development. The complex maternal-foetal interrelationships within the placental bed are essential for normal pregnancy, and decidua definitively contributes to the success of this process. Nevertheless, the molecular signalling network that coordinates strategies for successful decidualization and placentation are not well understood. The discovery of the endocannabinoid system highlighted new signalling mediators in various physiological processes, including reproduction. It is known that endocannabinoids present regulatory functions during blastocyst development, oviductal transport, and implantation. In addition, all the endocannabinoid machinery was found to be expressed in decidual and placental tissues. Additionally, endocannabinoid’s plasmatic levels were found to fluctuate during normal gestation and to induce decidual cell death and disturb normal placental development. Moreover, aberrant endocannabinoid signalling during the period of placental development has been associated with pregnancy disorders. It indicates the existence of a possible regulatory role for these molecules during decidualization and placentation processes, which are known to be particularly vulnerable. In this review, the influence of the endocannabinoid system in these critical processes is explored and discussed.

  10. Diet-induced obesity impairs endometrial stromal cell decidualization: a potential role for impaired autophagy.

    Science.gov (United States)

    Rhee, Julie S; Saben, Jessica L; Mayer, Allyson L; Schulte, Maureen B; Asghar, Zeenat; Stephens, Claire; Chi, Maggie M-Y; Moley, Kelle H

    2016-06-01

    What effect does diet-induced obesity have on endometrial stromal cell (ESC) decidualization? Diet-induced obesity impairs ESC decidualization. Decidualization is important for successful implantation and subsequent health of the pregnancy. Compared with normal-weight women, obese women have lower pregnancy rates (both spontaneous and by assisted reproductive technology), higher rates of early pregnancy loss and poorer oocyte quality. Beginning at 6 weeks of age, female C57Bl/6J mice were fed either a high-fat/high-sugar diet (HF/HS; 58% Fat Energy/Sucrose) or a diet of standard mouse chow (CON; 13% Fat) for 12 weeks. At this point, metabolic parameters were measured. Some of the mice (n = 9 HF/HS and 9 CON) were mated with reproductively competent males, and implantation sites were assessed. Other mice (n = 11 HF/HS and 10 CON) were mated with vasectomized males, and artificial decidualization was induced. For in vitro human studies of primary ESCs, endometrial tissue was obtained via biopsy from normo-ovulatory patients without history of infertility (obese = BMI > 30 kg/m(2), n = 11 and lean = BMI treatment with cAMP and medroxyprogesterone. The level of expression of decidualization markers was assessed by RT-qPCR (mRNA) and western blotting (protein). ATP content of ESCs was measured, and levels of autophagy were assessed by western blotting of the autophagy regulators acetyl coa carboxylase (ACC) and ULK1 (Ser 317). Autophagic flux was measured by western blot of the marker LC3b-II. Mice exposed to an HF/HS diet became obese and metabolically impaired. HF/HS-exposed mice mated to reproductively competent males had smaller implantation sites in early pregnancy (P obese women than in those of normal-weight women (Ptreatment abrogated this increase. Many aspects of obesity and metabolic impairment could contribute to the decidualization defects observed in the HF/HS-exposed mice. Although our findings suggest that both autophagy and decidualization are impaired

  11. Intra-annual dynamics of non-structural carbohydrates in the cambium of mature conifer trees reflects radial growth demands.

    Science.gov (United States)

    Simard, Sonia; Giovannelli, Alessio; Treydte, Kerstin; Traversi, Maria Laura; King, Gregory M; Frank, David; Fonti, Patrick

    2013-09-01

    The presence of soluble carbohydrates in the cambial zone, either from sugars recently produced during photosynthesis or from starch remobilized from storage organs, is necessary for radial tree growth. However, considerable uncertainties on carbohydrate dynamics and the consequences on tree productivity exist. This study aims to better understand the variation in different carbon pools at intra-annual resolution by quantifying how cambial zone sugar and starch concentrations fluctuate over the season and in relation to cambial phenology. A comparison between two physiologically different species growing at the same site, i.e., the evergreen Picea abies Karst. and the deciduous Larix decidua Mill., and between L. decidua from two contrasting elevations, is presented to identify mechanisms of growth limitation. Results indicate that the annual cycle of sugar concentration within the cambial zone is coupled to the process of wood formation. The highest sugar concentration is observed when the number of cells in secondary wall formation and lignification stages is at a maximum, subsequent to most radial growth. Starch disappears in winter, while other freeze-resistant non-structural carbohydrates (NSCs) increase. Slight differences in NSC concentration between species are consistent with the differing climate sensitivity of the evergreen and deciduous species investigated. The general absence of differences between elevations suggests that the cambial activity of trees growing at the treeline was not limited by the availability of carbohydrates at the cambial zone but instead by environmental controls on the growing season duration.

  12. Seeing the forest for the trees

    DEFF Research Database (Denmark)

    Ribbons, Relena Rose

    Tree species influence soils above and belowground communities through leaf litter and root inputs. Soil microbial communities can directly influence tree growth and development through processes such as decomposition of leaves, and indirectly through chemical transformation of nutrients in soils...... as an influence of altered C:N ratios due to leaf litter inputs. This thesis aims to document some of the mechanisms by which trees influence soil microbial communities and nitrogen cycling processes like gross and net ammonification and nitrification. This thesis also aims to determine the role of site nitrogen...... status on modulating those tree species effects. The effects of tree species on ammonification and nitrification rates in forest floors and mineral soils were explored, and related to functional genetic markers for ammonia-oxidation by archaea and bacteria (amoA AOA and AOB), bacterial denitrification...

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

    Directory of Open Access Journals (Sweden)

    Shouren Zhang

    2013-11-01

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

  14. Deciduous forest responses to temperature, precipitation, and drought imply complex climate change impacts.

    Science.gov (United States)

    Xie, Yingying; Wang, Xiaojing; Silander, John A

    2015-11-03

    Changes in spring and autumn phenology of temperate plants in recent decades have become iconic bio-indicators of rapid climate change. These changes have substantial ecological and economic impacts. However, autumn phenology remains surprisingly little studied. Although the effects of unfavorable environmental conditions (e.g., frost, heat, wetness, and drought) on autumn phenology have been observed for over 60 y, how these factors interact to influence autumn phenological events remain poorly understood. Using remotely sensed phenology data from 2001 to 2012, this study identified and quantified significant effects of a suite of environmental factors on the timing of fall dormancy of deciduous forest communities in New England, United States. Cold, frost, and wet conditions, and high heat-stress tended to induce earlier dormancy of deciduous forests, whereas moderate heat- and drought-stress delayed dormancy. Deciduous forests in two eco-regions showed contrasting, nonlinear responses to variation in these explanatory factors. Based on future climate projection over two periods (2041-2050 and 2090-2099), later dormancy dates were predicted in northern areas. However, in coastal areas earlier dormancy dates were predicted. Our models suggest that besides warming in climate change, changes in frost and moisture conditions as well as extreme weather events (e.g., drought- and heat-stress, and flooding), should also be considered in future predictions of autumn phenology in temperate deciduous forests. This study improves our understanding of how multiple environmental variables interact to affect autumn phenology in temperate deciduous forest ecosystems, and points the way to building more mechanistic and predictive models.

  15. Reconstructing the life-time lead exposure in children using dentine in deciduous teeth

    Energy Technology Data Exchange (ETDEWEB)

    Shepherd, Thomas J., E-mail: shepherdtj@aol.com [School of Earth and Environment, University of Leeds, Leeds LS2 9JT (United Kingdom); Dirks, Wendy [Centre for Oral Health Research, School of Dental Sciences, Newcastle University, Newcastle upon Tyne NE2 4BW (United Kingdom); Manmee, Charuwan; Hodgson, Susan [Institute of Health and Society, Newcastle University, Newcastle upon Tyne NE2 4AX (United Kingdom); Banks, David A. [School of Earth and Environment, University of Leeds, Leeds LS2 9JT (United Kingdom); Averley, Paul [Centre for Oral Health Research, School of Dental Sciences, Newcastle University, Newcastle upon Tyne NE2 4BW (United Kingdom); Queensway Dental Practice, 170 Queensway, Billingham, Teesside TS23 2NT (United Kingdom); Pless-Mulloli, Tanja [Institute of Health and Society, Newcastle University, Newcastle upon Tyne NE2 4AX (United Kingdom); Newcastle Institute for Research on Sustainability, Newcastle University, Newcastle upon Tyne NE1 7RU (United Kingdom)

    2012-05-15

    Data are presented to demonstrate that the circumpulpal dentine of deciduous teeth can be used to reconstruct a detailed record of childhood exposure to lead. By combining high spatial resolution laser ablation ICP-MS with dental histology, information was acquired on the concentration of lead in dentine from in utero to several years after birth, using a true time template of dentine growth. Time corrected lead analyses for pairs of deciduous molars confirmed that between-tooth variation for the same child was negligible and that meaningful exposure histories can be obtained from a single, multi-point ablation transect on longitudinal sections of individual teeth. For a laser beam of 100 {mu}m diameter, the lead signal for each ablation point represented a time span of 42 days. Simultaneous analyses for Sr, Zn and Mg suggest that the incorporation of Pb into dentine (carbonated apatite) is most likely controlled by nanocrystal growth mechanisms. The study also highlights the importance of discriminating between primary and secondary dentine and the dangers of translating lead analyses into blood lead estimates without determining the age or duration of dentine sampled. Further work is in progress to validate deciduous teeth as blood lead biomarkers. - Highlights: Black-Right-Pointing-Pointer Reconstruction of childhood exposure history to Pb using deciduous tooth dentine. Black-Right-Pointing-Pointer Pb analyses acquired for dentine growth increments of 42 days. Black-Right-Pointing-Pointer Highly correlated Pb concentration profiles for pairs of deciduous molars. Black-Right-Pointing-Pointer Data for Sr, Zn and Mg provide a model for the incorporation of Pb into dentine.

  16. Reconstructing the life-time lead exposure in children using dentine in deciduous teeth

    International Nuclear Information System (INIS)

    Shepherd, Thomas J.; Dirks, Wendy; Manmee, Charuwan; Hodgson, Susan; Banks, David A.; Averley, Paul; Pless-Mulloli, Tanja

    2012-01-01

    Data are presented to demonstrate that the circumpulpal dentine of deciduous teeth can be used to reconstruct a detailed record of childhood exposure to lead. By combining high spatial resolution laser ablation ICP-MS with dental histology, information was acquired on the concentration of lead in dentine from in utero to several years after birth, using a true time template of dentine growth. Time corrected lead analyses for pairs of deciduous molars confirmed that between-tooth variation for the same child was negligible and that meaningful exposure histories can be obtained from a single, multi-point ablation transect on longitudinal sections of individual teeth. For a laser beam of 100 μm diameter, the lead signal for each ablation point represented a time span of 42 days. Simultaneous analyses for Sr, Zn and Mg suggest that the incorporation of Pb into dentine (carbonated apatite) is most likely controlled by nanocrystal growth mechanisms. The study also highlights the importance of discriminating between primary and secondary dentine and the dangers of translating lead analyses into blood lead estimates without determining the age or duration of dentine sampled. Further work is in progress to validate deciduous teeth as blood lead biomarkers. - Highlights: ► Reconstruction of childhood exposure history to Pb using deciduous tooth dentine. ► Pb analyses acquired for dentine growth increments of 42 days. ► Highly correlated Pb concentration profiles for pairs of deciduous molars. ► Data for Sr, Zn and Mg provide a model for the incorporation of Pb into dentine.

  17. TREE2FASTA: a flexible Perl script for batch extraction of FASTA sequences from exploratory phylogenetic trees.

    Science.gov (United States)

    Sauvage, Thomas; Plouviez, Sophie; Schmidt, William E; Fredericq, Suzanne

    2018-03-05

    The body of DNA sequence data lacking taxonomically informative sequence headers is rapidly growing in user and public databases (e.g. sequences lacking identification and contaminants). In the context of systematics studies, sorting such sequence data for taxonomic curation and/or molecular diversity characterization (e.g. crypticism) often requires the building of exploratory phylogenetic trees with reference taxa. The subsequent step of segregating DNA sequences of interest based on observed topological relationships can represent a challenging task, especially for large datasets. We have written TREE2FASTA, a Perl script that enables and expedites the sorting of FASTA-formatted sequence data from exploratory phylogenetic trees. TREE2FASTA takes advantage of the interactive, rapid point-and-click color selection and/or annotations of tree leaves in the popular Java tree-viewer FigTree to segregate groups of FASTA sequences of interest to separate files. TREE2FASTA allows for both simple and nested segregation designs to facilitate the simultaneous preparation of multiple data sets that may overlap in sequence content.

  18. Dendrochronological Investigations of Valonia Oak Trees in Western Greece

    Directory of Open Access Journals (Sweden)

    Andreas Papadopoulos

    2016-06-01

    Full Text Available Background and Purpose: Valonia oak (Quercus ithaburensis subsp. macrolepis (Kotschy Hedge & Yalt. is an east Mediterranean endemic, xerothermic and deciduous tree of particular interest in forestry. There has been a growing demand lately to include the species in reforestations in Greece which also increased the interest to investigate its response to climate change. The main purpose of this research is to study valonia oak from a dendrochronological – dendroclimatological point of view within its Mediterranean distribution range. Materials and Methods: Sampling took place in characteristic valonia oak stands where cross sections or tree-cores were taken from 40 trees. The cross sections and the tree-cores were prepared and cross-dated using standard dendrochronological methods and tree-ring widths were measured to the nearest 0.001 mm using the Windendro software program. The ARSTAN program was used to standardize the tree-ring data and to calculate dendrochronological statistical parameters. The inter-annual variability of tree-ring width and the radial growth trend were examined. Finally, tree-ring widths to climate relationships were calculated by orthogonal regression in combination with the bootstrap procedure using master residual chronology and monthly precipitation, temperature data and scPDSI drought index, from October of the n-1 year up to November of the n year. Results: The master chronology of valonia oak trees in Western Greece reaches 365 years, with an average ring width of 0.89 mm and with mean sensitivity being 0.21. The variation of the tree-ring widths indicates the influence of climate and human intervention in the past. Tree-ring to climate relationships show that valonia oak growth is positively affected by precipitations in January and March and by drought reduction during June and July. Conclusions: Valonia oak in Western Greece is a species of great interest for dendrochronological and dendroclimatological studies

  19. Induction of Mitochondria Mediated Apoptosis in Human Breast Cancer Cells (T-47D) by Annona reticulata L. Leaves Methanolic Extracts.

    Science.gov (United States)

    Roham, Pratiksha H; Kharat, Kiran R; Mungde, Priyanka; Jadhav, Mahadev A; Makhija, Surinder J

    2016-01-01

    Annona reticulata Linn. (Common name: Bullock's-heart) (Annonaceae family) is a semi-evergreen and small deciduous tree. The extracts of various parts of Annona reticulata L. have been reported as cytotoxic to many cancer cells. Annona reticulata L. leaves' methanolic extract (ARME) was prepared and used against the breast cancer cells. The breast cancer cells (T-47D) viability and IC50 were evaluated by Vybrant® MTT Cell Proliferation Assay Kit. Detection of phosphatidylserine on membranes of apoptotic cells was done by Attune flow cytometer. RNA transcripts were quantified in ARME treated and untreated cells. Finally, the Vybrant® FAM Poly Caspases assay kit was used for analysis of polycaspases activity in T-47D cells. The IC50 (5 ± 0.5 µg/mL) of the ARME was found against breast cancer cells (T-47D). The Paclitaxel was used as a control standard drug for the study. The downregulation of Bcl-2 and upregulation of Bax and Bak, and caspases activation suggested induction of apoptosis in T-47D cells by ARME through mitochondrial pathway. The cell cycle halted at G2/M phase in the ARME treated cells. The ARME was found to be effective against Breast cancer cells (T-47D).

  20. Tree size as a factor influencing leaf emergence and leaf fall in Acacia nigrescens and Combretum apiculatum in the Kruger National Park

    Directory of Open Access Journals (Sweden)

    P. Novellie

    1989-10-01

    Full Text Available In Acacia nigrescens and Combretum apiculatum saplings tended to retain leaves over the dry season, whereas the mature trees generally lost most of their leaves. In Acacia nigrescens the production of new leaves over the dry season was more commonly observed in saplings than in mature trees.

  1. Modified distal shoe appliance for premature loss of multiple deciduous molars: a case report.

    Science.gov (United States)

    Bhat, Prasanna Kumar; K, Navin H; Idris, Mohammed; Christopher, Pradeep; Rai, Niharika

    2014-08-01

    Preservation of the primary dentition until the normal time of exfoliation is one of the most important factor involved in preventive and interceptive dentistry. The premature loss of second primary molar before the eruption of permanent first molar can create a significant arch space/tooth size discrepancy. Distal shoe space maintainer is a valuable part of the Paediatric Dentist's armamentarium in those cases where the second primary molar is prematurely lost and it helps to guide the first permanent molar into place. Conventional design poses various limitations in cases of premature loss of multiple deciduous molars. Thus, it is required to modify the conventional designs according to the needs of the patient. This case report describes an innovative modification of distal shoe appliance in cases of premature loss of multiple deciduous molars. In the present case, modification of distal shoe space maintainer was advocated because of inadequate abutments caused due to multiple loss of deciduous molars. Bilateral design of distal shoe was planned for unilateral loss of deciduous molars.

  2. Belowground uptake strategies: how fine-root traits determine tree growth

    NARCIS (Netherlands)

    Weemstra, Monique

    2017-01-01

    The growth of trees depends on photosynthetic carbon gain by the leaves, which in turn relies on water and nutrient acquisition by the fine roots. Because the availability of carbon, water and nutrients fluctuates, trees can adjust their leaf and fine-root functional traits to maintain their

  3. Delonix regia Rat. (Gulmohar) is a highly ornamental tree largely ...

    Indian Academy of Sciences (India)

    Delonix regia Rat. (Gulmohar) is a highly ornamental tree largely cultivated on roadsides and in gardens for its beautiful foliage and scarlet red (lowers. Gulmohar trees in full bloom and new leaves dominate other flora in summer months. The infusion of flowers is used in bronchitis, asthma and malaria.

  4. Uptake and translocation of radiocesium in cedar leaves following the Fukushima nuclear accident

    International Nuclear Information System (INIS)

    Nishikiori, Tatsuhiro; Watanabe, Mirai; Koshikawa, Masami K.; Takamatsu, Takejiro; Ishii, Yumiko; Ito, Shoko; Takenaka, Akio; Watanabe, Keiji; Hayashi, Seiji

    2015-01-01

    Cryptomeria japonica trees in the area surrounding Fukushima, Japan, intercepted 137 Cs present in atmospheric deposits soon after the Fukushima nuclear accident in March 2011. To study the uptake and translocation of 137 Cs in C. japonica leaves, we analyzed activity concentrations of 137 Cs and the concentration ratios of 137 Cs to 133 Cs ( 137 Cs/ 133 Cs) in old and new leaves of C. japonica collected from a forest on Mount Tsukuba between 9 and 15 months after the accident. Both isotopes were also analyzed in throughfall, bulk precipitation and soil extracts. Water of atmospheric and soil origin were used as proxies for deciphering the absorption from leaf surfaces and root systems, respectively. Results indicate that 20–40% of foliar 137 Cs existed inside the leaf, while 60–80% adhered to the leaf surface. The 137 Cs/ 133 Cs ratios inside leaves that had sprouted before the accident were considerably higher than that of the soil extract and lower than that of throughfall and bulk precipitation. Additionally, more than 80% of 137 Cs in throughfall and bulk precipitation was present in the dissolved form, which is available for foliar uptake, indicating that a portion of the 137 Cs inside old leaves was presumably absorbed from the leaf surface. New leaves that sprouted after the accident had similar 137 Cs/ 133 Cs ratios to that of the old leaves, suggesting that internal 137 Cs was translocated from old to new leaves. For 17 species of woody plants other than C. japonica, new leaves that sprouted after the accident also contained 137 Cs, and their 137 Cs/ 133 Cs ratios were equal to or higher than that of the soil extract. These results suggested that foliar uptake and further translocation of 137 Cs is an important vector of contamination in various tree species during or just after radioactive fallout. - Highlights: • 137 Cs was absorbed into cedar leaves from the leaf surface. • 137 Cs in new leaves of cedar trees was mainly supplied by

  5. Uptake and translocation of radiocesium in cedar leaves following the Fukushima nuclear accident

    Energy Technology Data Exchange (ETDEWEB)

    Nishikiori, Tatsuhiro [Center for Regional Environment Research, National Institute for Environmental Studies, 16-2 Onogawa, Tsukuba, Ibaraki 305-8506 (Japan); Watanabe, Mirai, E-mail: watanabe.mirai@nies.go.jp [Center for Regional Environment Research, National Institute for Environmental Studies, 16-2 Onogawa, Tsukuba, Ibaraki 305-8506 (Japan); Koshikawa, Masami K.; Takamatsu, Takejiro; Ishii, Yumiko; Ito, Shoko [Center for Regional Environment Research, National Institute for Environmental Studies, 16-2 Onogawa, Tsukuba, Ibaraki 305-8506 (Japan); Takenaka, Akio [Center for Environmental Biology and Ecosystem Studies, National Institute for Environmental Studies, 16-2 Onogawa, Tsukuba, Ibaraki 305-8506 (Japan); Watanabe, Keiji [Center for Regional Environment Research, National Institute for Environmental Studies, 16-2 Onogawa, Tsukuba, Ibaraki 305-8506 (Japan); Center for Environmental Science in Saitama, 914 Kamitanadare, Kazo, Saitama 347-0115 (Japan); Hayashi, Seiji [Center for Regional Environment Research, National Institute for Environmental Studies, 16-2 Onogawa, Tsukuba, Ibaraki 305-8506 (Japan)

    2015-01-01

    Cryptomeria japonica trees in the area surrounding Fukushima, Japan, intercepted {sup 137}Cs present in atmospheric deposits soon after the Fukushima nuclear accident in March 2011. To study the uptake and translocation of {sup 137}Cs in C. japonica leaves, we analyzed activity concentrations of {sup 137}Cs and the concentration ratios of {sup 137}Cs to {sup 133}Cs ({sup 137}Cs/{sup 133}Cs) in old and new leaves of C. japonica collected from a forest on Mount Tsukuba between 9 and 15 months after the accident. Both isotopes were also analyzed in throughfall, bulk precipitation and soil extracts. Water of atmospheric and soil origin were used as proxies for deciphering the absorption from leaf surfaces and root systems, respectively. Results indicate that 20–40% of foliar {sup 137}Cs existed inside the leaf, while 60–80% adhered to the leaf surface. The {sup 137}Cs/{sup 133}Cs ratios inside leaves that had sprouted before the accident were considerably higher than that of the soil extract and lower than that of throughfall and bulk precipitation. Additionally, more than 80% of {sup 137}Cs in throughfall and bulk precipitation was present in the dissolved form, which is available for foliar uptake, indicating that a portion of the {sup 137}Cs inside old leaves was presumably absorbed from the leaf surface. New leaves that sprouted after the accident had similar {sup 137}Cs/{sup 133}Cs ratios to that of the old leaves, suggesting that internal {sup 137}Cs was translocated from old to new leaves. For 17 species of woody plants other than C. japonica, new leaves that sprouted after the accident also contained {sup 137}Cs, and their {sup 137}Cs/{sup 133}Cs ratios were equal to or higher than that of the soil extract. These results suggested that foliar uptake and further translocation of {sup 137}Cs is an important vector of contamination in various tree species during or just after radioactive fallout. - Highlights: • {sup 137}Cs was absorbed into cedar leaves

  6. Investigation of Tree Spectral Reflectance Characteristics Using a Mobile Terrestrial Line Spectrometer and Laser Scanner

    Directory of Open Access Journals (Sweden)

    Eetu Puttonen

    2013-07-01

    Full Text Available In mobile terrestrial hyperspectral imaging, individual trees often present large variations in spectral reflectance that may impact the relevant applications, but the related studies have been seldom reported. To fill this gap, this study was dedicated to investigating the spectral reflectance characteristics of individual trees with a Sensei mobile mapping system, which comprises a Specim line spectrometer and an Ibeo Lux laser scanner. The addition of the latter unit facilitates recording the structural characteristics of the target trees synchronously, and this is beneficial for revealing the characteristics of the spatial distributions of tree spectral reflectance with variations at different levels. Then, the parts of trees with relatively low-level variations can be extracted. At the same time, since it is difficult to manipulate the whole spectrum, the traditional concept of vegetation indices (VI based on some particular spectral bands was taken into account here. Whether the assumed VIs capable of behaving consistently for the whole crown of each tree was also checked. The specific analyses were deployed based on four deciduous tree species and six kinds of VIs. The test showed that with the help of the laser scanner data, the parts of individual trees with relatively low-level variations can be located. Based on these parts, the relatively stable spectral reflectance characteristics for different tree species can be learnt.

  7. What happens to living cull trees left after heavy cutting in mixed hardwood stands?

    Science.gov (United States)

    George R., Jr. Trimble; Henry Clay Smith

    1963-01-01

    In the Appalachian Mountains, the logging operator usually cuts only those trees that he thinks will yield a profit, and leaves the trees that appear to be unprofitable. Generally these unprofitable trees are either below merchantable size or are culls-trees of merchantable size that contain too little sound material to justify harvesting costs.

  8. Flammulated Owls (Otus flammeolus) breeding in deciduous forests

    Science.gov (United States)

    Carl D. Marti

    1997-01-01

    The first studies of nesting Flammulated Owls (Otus flammeolus) established the idea that the species needs ponderosa pine (Pinus ponderosa) forests for breeding. In northern Utah, Flammulated Owls nested in montane deciduous forests dominated by quaking aspen (Populus tremuloides). No pines were present but...

  9. Influence of Environmental Pollution on Leaf Properties of Urban Plane Trees, Platanus orientalis L.

    Science.gov (United States)

    Pourkhabbaz, Alireza; Rastin, Nayerah; Olbrich, Andrea; Langenfeld-Heyser, Rosemarie

    2010-01-01

    To investigate whether leaves of plane trees (Platanus orientalis) are damaged by traffic pollution, trees from a megacity (Mashhad, Iran) and a rural area were investigated. Soil and air from the urban centre showed enrichment of several toxic elements, but only lead was enriched in leaves. Leaf size and stomata density were lower at the urban site. At the urban site leaf surfaces were heavily loaded by dust particles but the stomata were not occluded; the cuticle was thinner; other anatomical properties were unaffected suggesting that plane trees can cope with traffic exhaust in megacities. PMID:20577871

  10. Response of Quercus velutina growth and water use efficiency to climate variability and nitrogen fertilization in a temperate deciduous forest in the northeastern USA.

    Science.gov (United States)

    Jennings, Katie A; Guerrieri, Rossella; Vadeboncoeur, Matthew A; Asbjornsen, Heidi

    2016-04-01

    Nitrogen (N) deposition and changing climate patterns in the northeastern USA can influence forest productivity through effects on plant nutrient relations and water use. This study evaluates the combined effects of N fertilization, climate and rising atmospheric CO2on tree growth and ecophysiology in a temperate deciduous forest. Tree ring widths and stable carbon (δ(13)C) and oxygen (δ(18)O) isotopes were used to assess tree growth (basal area increment, BAI) and intrinsic water use efficiency (iWUE) ofQuercus velutinaLamb., the dominant tree species in a 20+ year N fertilization experiment at Harvard Forest (MA, USA). We found that fertilized trees exhibited a pronounced and sustained growth enhancement relative to control trees, with the low- and high-N treatments responding similarly. All treatments exhibited improved iWUE over the study period (1984-2011). Intrinsic water use efficiency trends in the control trees were primarily driven by changes in stomatal conductance, while a stimulation in photosynthesis, supported by an increase in foliar %N, contributed to enhancing iWUE in fertilized trees. All treatments were predominantly influenced by growing season vapor pressure deficit (VPD), with BAI responding most strongly to early season VPD and iWUE responding most strongly to late season VPD. Nitrogen fertilization increasedQ. velutinasensitivity to July temperature and precipitation. Combined, these results suggest that ambient N deposition in N-limited northeastern US forests has enhanced tree growth over the past 30 years, while rising ambient CO2has improved iWUE, with N fertilization and CO2having synergistic effects on iWUE. © The Author 2016. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  11. In vitro evaluation of fluoride products in the development of carious lesions in deciduous teeth

    Directory of Open Access Journals (Sweden)

    Lucineide de Melo Santos

    2009-09-01

    Full Text Available The purpose of this study was to evaluate the effect of the application of fluoride products on the development of enamel caries in deciduous teeth. A total of 108 deciduous teeth were chosen for the study. Acid-resistant varnish was applied on the teeth, leaving only one area of 5 mm x 1 mm of dental enamel exposed. The teeth were allocated randomly to one of the following groups: 1 control - toothpaste without fluoride; 2 1.23% fluoride gel; 3 Duraflur fluoride varnish; 4 Duraphat fluoride varnish; 5 Fluorniz fluoride varnish; 6 Fluorphat fluoride varnish; 7 varnish with Duofluorid; 8 12% silver fluoride diamine (Cariestop; 9 children's fluoride toothpaste (500 ppm. The tested products were applied on the teeth according to the manufacturer's recommendations and the teeth were stored in a moist environment for 24 hours. Each group of teeth was then subjected to a pH cycling model for 14 days, after which the teeth were cut through the center for an analysis of the depth of the carious lesion by polarized light microscopy. Comparisons were made between the treatments and the control group. The mean lesion depth values were 318 μm ± 39 (control, 213 μm ± 27 (fluoride gel, 203 μm ± 34 (Duraflur, 133 μm ± 25 (Duraphat, 207 μm ± 27 (Fluor-niz, 212 μm ± 27 (Fluorphat, 210 ± 28 (Duofluorid, 146 ± 31 (Cariestop and 228 ± 24 (fluoride toothpaste. None of the products used here was able to completely prevent the formation of lesions. The highest cariostatic effect was achieved by fluoride varnish Duraphat and the lowest by the fluoride toothpaste.

  12. Phytosociology analysis of a fragment of Seasonal Deciduous Forest: Parque Estadual do Turvo, RS, Brazil

    Directory of Open Access Journals (Sweden)

    Rafaelo Balbinot

    2016-06-01

    Full Text Available The ecosystem formed by the Seasonal Deciduous Forest (SDF predominates in the region of Alto Uruguay in Rio Grande do Sul State, Brazil. This study aimed to analyze descriptively the floristic composition and the phytosociology of trees from a fragment of SDF present in Parque Estadual do Turvo (PET located in the Municipality of Derrubadas, Rio Grande do Sul State (Yucumã forest. We used the method of fixed area, based on 18 sample units with 1,000 m2 installed randomly oriented by the main road of the park. All wood species with diameter at 1.3 m above ground level (DBH greater than 10 cm were measured and identified. It was observed the presence of 842 individuals belonging to 32 families, 67 genera and 83 species (12% were not identified. The families with the highest number of species were Fabaceae, Euphorbiaceae, Meliaceae, Myrtaceae and Sapindaceae. Shannon index estimated was 3.72.

  13. Top tips from tree tops

    Science.gov (United States)

    Ornes, Stephen

    2018-04-01

    The ability of trees to cool by transporting water from their roots to the leaves has been known for centuries. But as Stephen Ornes discovers, the principles of transpiration are also inspiring innovative techniques to cool vehicles travelling at hypersonic speeds, where unwanted heat is a problem too

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

    Science.gov (United States)

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

    2016-12-01

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

  15. Leaf protein and mineral concentrations across the "miracle tree" genus Moringa

    Science.gov (United States)

    The moringa tree Moringa oleifera is a fast-growing, drought-resistant tree cultivated across the lowland dry tropics worldwide for its nutritious leaves. Despite its nutritious reputation, there has been no systematic survey of the variation in leaf nutritional quality across M. oleifera grown worl...

  16. [Mahalanobis distance based hyperspectral characteristic discrimination of leaves of different desert tree species].

    Science.gov (United States)

    Lin, Hai-jun; Zhang, Hui-fang; Gao, Ya-qi; Li, Xia; Yang, Fan; Zhou, Yan-fei

    2014-12-01

    The hyperspectral reflectance of Populus euphratica, Tamarix hispida, Haloxylon ammodendron and Calligonum mongolicum in the lower reaches of Tarim River and Turpan Desert Botanical Garden was measured by using the HR-768 field-portable spectroradiometer. The method of continuum removal, first derivative reflectance and second derivative reflectance were used to deal with the original spectral data of four tree species. The method of Mahalanobis Distance was used to select the bands with significant differences in the original spectral data and transform spectral data to identify the different tree species. The progressive discrimination analyses were used to test the selective bands used to identify different tree species. The results showed that The Mahalanobis Distance method was an effective method in feature band extraction. The bands for identifying different tree species were most near-infrared bands. The recognition accuracy of four methods was 85%, 93.8%, 92.4% and 95.5% respectively. Spectrum transform could improve the recognition accuracy. The recognition accuracy of different research objects and different spectrum transform methods were different. The research provided evidence for desert tree species classification, monitoring biodiversity and the analysis of area in desert by using large scale remote sensing method.

  17. Management of unerupted maxillary deciduous central incisor: a case report.

    Science.gov (United States)

    Shakra, Karam Abu

    2014-01-01

    Failure of eruption of primary teeth can be considered rare, especially in maxillary anterior teeth. The problem can be either mechanical obstruction of eruption or a failure of the eruption mechanism. This case report presents failure of eruption of the maxillary right deciduous central incisor in a 4-year-old girl. The unerupted primary tooth was removed surgically. The histological finding revealed fibroma with reactive giant cells. Periodic follow-up visits were advised to monitor the developing dentition and to ensure enough space for the permanent incisor. How to cite this article: Shakra KA. Management of Unerupted Maxillary Deciduous Central Incisor: A Case Report. Int J Clin Pediatr Dent 2014;7(1):58-60.

  18. Biomimicry of Palm Tree Leaves Form and Pattern on Building Form

    Directory of Open Access Journals (Sweden)

    Agus Salim N.A.

    2014-01-01

    Full Text Available This article is a study on biomimicry of palm tree towards a building form. It is to find a suitable form and pattern that can be applied to building shell to ease building maintenance operation beside to enhance the aesthetic value of a building architecture. The research has been carried out by observation and modeling on some various species of palm tree’s patterns and forms. The result expectation can be found at the end of this research by producing the best pattern of palm tree that can be adapted to building envelop as the whole form of a building.

  19. Shapes of tree representations of spin-glass landscapes

    International Nuclear Information System (INIS)

    Hordijk, Wim; Fontanari, Jose F; Stadler, Peter F

    2003-01-01

    Much of the information about the multi-valley structure of disordered spin systems can be convened in a simple tree structure - a barrier tree - the leaves and internal nodes of which represent, respectively, the local minima and the lowest energy saddles connecting those minima. Here we apply several statistics used in the study of phylogenetic trees to barrier trees that result from the energy landscapes of p-spin models. These statistics give information about the shape of these barrier trees, in particular about balance and symmetry. We then ask if they can be used to classify different types of landscapes, compare them with results obtained from random trees, and investigate the structure of subtrees of the barrier trees. We conclude that at least one of the used statistics is capable of distinguishing different types of landscapes, that the barrier trees from p-spin energy landscapes are quite different from random trees, and that subtrees of barrier trees do not reflect the overall tree structure, but their structure is correlated with their 'depth' in the tree

  20. Dust collection capacity of plants growing in coal mining areas

    International Nuclear Information System (INIS)

    Maiti, S.K.

    1993-01-01

    Plant can act as living filter of dust pollution in coal mining areas, where the amount of suspended particulate matter and dust fall rate is very high. Therefore, plant species growing in coal mining areas are classified as evergreen or deciduous with simple and compound leaf basis. The dust arresting capacity of each leaf is measured and expressed in g/m 2 . The study indicated that evergreen plants with simple, pilose surface, like - Alstonia, Ficus cunea, F. benghalensis and Mangifera indica are good dust catcher than evergreen compound leaves of Cassia siamea, Acacia arabica and Leucaena leucocephala. Deciduous with simple leaves, such as Zizyphus mauritiana, F. religiosa, Psidium guyava are also good dust collectors. Suitable plant species also help in quick reclamation of mined out areas; one practical difficulty for establishment of trees as green belts or reclamation purpose, has been incidence of cattle grazing. This study suggested a systematic way of selecting plant species on the basis of their efficiency in dust control and resistance to cattle grazing. (author). 16 refs., 3 tabs

  1. Relationship between Leaf Surface Characteristics and Particle Capturing Capacities of Different Tree Species in Beijing

    Directory of Open Access Journals (Sweden)

    Weikang Zhang

    2017-03-01

    Full Text Available Leaf surface is a multifunctional interface between a plant and its environment, which affects both ecological and biological processes. Leaf surface topography directly affects microhabitat availability and ability for deposition. In this study, atomic force microscopy (AFM and the resuspended particulate matter method were applied to evaluate the adsorptive capacity of the leaf surface. Patterns of particulate‐capturing capacities in different tree species and the effect of leaf surface features on these capacities were explored. Results indicated the following: (1 more total suspended particles (TSP per unit leaf area were captured by coniferous tree species than by broad‐leaved tree species in a particular order—i.e., Pinus tabuliformis > Pinus bungeana > Salix matsudana > Acer truncatum > Ginkgo biloba > Populus tomentosa; (2 Significant seasonal variation in particulate‐capturing capacities were determined. During the observation period, the broad‐leaved tree species capturing TSP and coarse particulate matter (PM10 clearly exhibited a ∩‐shape pattern— that is, increasing initially and later on decreasing; meanwhile, the ∩‐shape pattern was not clearly shown in P. tabuliformis and P. bungeana. However, no obvious patterns in the absorption of fine particulate matter (PM2.5 were found in the tested tree species; (3 The leaf surface topography, as observed by AFM and scanning electron microscopy, revealed that the broad‐leaved tree exhibits a good correlation between micro‐roughness of leaf surfaces and density of particles settling on leaf surfaces over time. However, the main factors affecting the adsorptive capacities of the leaves in coniferous trees are the number of stomata as well as the amount of epicuticular wax and the properties of the cuticle in different seasons.

  2. Reconstructing Unrooted Phylogenetic Trees from Symbolic Ternary Metrics.

    Science.gov (United States)

    Grünewald, Stefan; Long, Yangjing; Wu, Yaokun

    2018-03-09

    Böcker and Dress (Adv Math 138:105-125, 1998) presented a 1-to-1 correspondence between symbolically dated rooted trees and symbolic ultrametrics. We consider the corresponding problem for unrooted trees. More precisely, given a tree T with leaf set X and a proper vertex coloring of its interior vertices, we can map every triple of three different leaves to the color of its median vertex. We characterize all ternary maps that can be obtained in this way in terms of 4- and 5-point conditions, and we show that the corresponding tree and its coloring can be reconstructed from a ternary map that satisfies those conditions. Further, we give an additional condition that characterizes whether the tree is binary, and we describe an algorithm that reconstructs general trees in a bottom-up fashion.

  3. Application of micro-PIXE analysis to investigate trace elements in deciduous teeth enamel

    International Nuclear Information System (INIS)

    Igari, K.; Takahashi, A.; Ando, H.

    2010-01-01

    The early life environment has widespread consequences for later health and disease. To prevent the disease in later life, the assessment of fetal environment is very important. In Japan, birthweight has fallen rapidly during recent two decades. The reduction of birthweight represents reduced fetal nutrition. Deciduous tooth enamel contains pre- and postnatal enamel and its chemical composition reflects the status of metabolism of trace elements during formation period. Deciduous tooth enamel is considered to be a suitable indicator of trace elements exposure in utero. We applied micro-PIXE analysis to investigate the trace elemental content in deciduous tooth enamel. Two deciduous canines from one healthy Japanese boy were used for this study. The enamel section including pre- and postnatal enamel was prepared for micro-PIXE analysis. Five trace elements (Na, Mg, Cl, Zn, and Sr) were detected in the scanning area of tooth. The distribution profiles of 5 elements were obtained as X-ray maps. The distribution profiles of zinc and chlorine were specific, and showed higher concentration in surface enamel. No elements showed different profiles of X-ray maps between pre- and postnatal enamel in this sample. The results of this study suggested that micro-PIXE analysis would be able to estimate the trace elements in prenatal and postnatal enamel, respectively. (author)

  4. Steiner trees for fixed orientation metrics

    DEFF Research Database (Denmark)

    Brazil, Marcus; Zachariasen, Martin

    2009-01-01

    We consider the problem of constructing Steiner minimum trees for a metric defined by a polygonal unit circle (corresponding to s = 2 weighted legal orientations in the plane). A linear-time algorithm to enumerate all angle configurations for degree three Steiner points is given. We provide...... a simple proof that the angle configuration for a Steiner point extends to all Steiner points in a full Steiner minimum tree, such that at most six orientations suffice for edges in a full Steiner minimum tree. We show that the concept of canonical forms originally introduced for the uniform orientation...... metric generalises to the fixed orientation metric. Finally, we give an O(s n) time algorithm to compute a Steiner minimum tree for a given full Steiner topology with n terminal leaves....

  5. Carbon, cesium and iodine isotopes in Japanese cedar leaves from Iwaki, Fukushima

    DEFF Research Database (Denmark)

    Xu, Sheng; Cook, Gordon T.; Cresswell, Alan J.

    2016-01-01

    Japanese cedar leaves from Iwaki, Fukushima were analyzed for carbon, cesium and iodine isotopic compositions before and after the 2011 nuclear accident. The Δ14C values reflect ambient atmospheric 14C concentrations during the year the leaves were sampled/defoliated, and also previous year......(s). The elevated 129I and 134,137Cs concentrations are attributed to direct exposure to the radioactive fallout for the pre-fallout-expended leaves and to internal translocation from older parts of the tree for post-fallout-expended leaves. 134Cs/137Cs and 129I/137Cs activity ratios suggest insignificant isotopic...

  6. Evaluation of radiocesium concentrations in new leaves of wild plants two years after the Fukushima Dai-ichi Nuclear Power Plant accident.

    Science.gov (United States)

    Sugiura, Yuki; Shibata, Michihiro; Ogata, Yoshimune; Ozawa, Hajime; Kanasashi, Tsutomu; Takenaka, Chisato

    2016-08-01

    Radiocesium ((137)Cs) transfer to plants immediately after the Fukushima Dai-ichi Nuclear Power Plant accident was investigated by collecting newly emerged leaf and soil samples between May 2011 and November 2012 from 20 sites in the Fukushima prefecture. Radiocesium concentrations in leaf and soil samples were measured to calculate concentration ratios (CR). Woody plants exhibited high CR values because (137)Cs deposited on stems and/or leaves were transferred to newly emerging tissues. The CR values in 2012 declined as compared to that in 2011. Exchangeable (137)Cs rates in soil (extraction rate) samples were measured at five sites. These rates decreased at four sites in 2012 and depended on environmental conditions and soil type. Both CR values and extraction rates decreased in 2012. However, CR values reflected the changes in extraction rates and characteristics of each species. Amaranthaceae, Chenopodiaceae, and Polygonaceae, which had been identified as Cs accumulators, presented no clear (137)Cs accumulation ability. In 2012, the perennial plant Houttuynia cordata and deciduous trees Chengiopanax sciadophylloides and Acer crataegifolium displayed high CR values, indicating that these species are (137)Cs accumulators and may be considered as potential species for phytoremediation. Copyright © 2016 Elsevier Ltd. All rights reserved.

  7. Injuries caused to fruit trees by fluorine containing gases

    Energy Technology Data Exchange (ETDEWEB)

    Bovay, E

    1958-01-01

    Determinations of chlorine and fluorine have been made on leaves of various fruit trees growing in the vicinity of two factories, the first one being an aluminium factory and the second one a soda factory. The gases released by the first factory are of the fluorine type and those of the second one of the chlorine type. While the concentrations of fluorine are generally higher than 10 mg per 100 g of leaf dry matter, they hardly reached 2.5 mg% in 1957; the aluminium factory was not in operation that year. Moreover no symptoms of burns were observed in 1957 on the leaves of the fruit trees. In contrast to fluorine, the concentrations of chlorine remained constant.

  8. Orange Is the New Green: Exploring the Restorative Capacity of Seasonal Foliage in Schoolyard Trees

    Directory of Open Access Journals (Sweden)

    Eli Paddle

    2016-05-01

    Full Text Available Urban schoolyard environments are increasingly characterized by a proliferation of hard surfaces with little if any greenery. Schoolyard “greening” initiatives are becoming increasingly popular; however, schoolyard designs often fail to realize their restorative potential. In this quasi-experimental study, a proposed schoolyard greening project was used to visualize alternative planting designs and seasonal tree foliage; these design alternatives were subsequently used as visual stimuli in a survey administered to children who will use the schoolyard to assess the perceived restorative capacity of different design features. The findings indicate that seasonal changes in tree foliage enhance the perceived restorative quality of schoolyard environments. Specifically, fall foliage colour, when compared to green foliage, is rated as being perceived to be equally restorative for children. Additionally, seasonal planting, including evergreen conifers, may enhance the restorative quality of the schoolyard especially when deciduous trees are leafless. Landscape design professionals, community-based organizations, and other decision-makers in schoolyard greening efforts should strategically consider their tree choices to maximize year-round support for healthy attention functioning in children through restoration.

  9. Decontamination effects of bark washing with a high-pressure washer on Peach [Prunus persica (L.) Batsch] and Japanese Persimmon (Diospyros kaki Thunb.) contaminated with radiocaesium during dormancy

    International Nuclear Information System (INIS)

    Sato, Mamoru; Abe, Kazuhiro; Kikunaga, Hidetoshi; Ohtsuki, Tsutomu; Takata, Daisuke; Tanoi, Keitaro; Muramatsu, Yasuyuki

    2015-01-01

    The effect of bark washing with a high-pressure washer on deciduous trees contaminated during dormancy by radiocaesium fallout derived from the Fukushima Daiichi Nuclear Power Plant accident was examined using peach [Prunus persica (L.) Batsch] and Japanese persimmon (Diospyros kaki Thunb.). Eighteen-year-old peach trees ('Akatsuki') were bark-washed twice with a high-pressure washer on July 5 and 27, 2011. Seven-year-old peach trees ('Kawanakajima Hakuto') were bark-washed on January 24, 2012, and thirty-year-old Japanese persimmon trees ('Hachiya') were bark-washed on December 21, 2011. For the peach trees, most of the bark was not removed by washing with a high-pressure washer. In contrast, the rough bark of Japanese persimmon was removed completely. No significant differences in the 137 Cs concentration of 'Akatsuki' fruit were found between the treatments conducted in the summer of 2011. Upon the bark washing of peach 'Akatsuki' trees in summer, the possibility of secondary contamination of leaves via the leachate containing 137 Cs was likely. The 137 Cs concentrations in fruits and leaves of peach 'Kawanakajima Hakuto' collected in summer 2012 were decreased significantly by washing treatment conducted in winter 2011–2012. In the year after treatment, the 137 Cs concentrations in fruits and leaves of Japanese persimmon were significantly decreased by the treatment. The effect of the bark washing on decreasing 137 Cs contents in fruits and leaves was greater in Japanese persimmon than in peach. The results for 'Kawanakajima Hakuto' and 'Hachiya' demonstrated the possibility of additive contamination. (author)

  10. Determination of atmospheric SO/sub 2/ concentrations that are dangerous to plant life

    Energy Technology Data Exchange (ETDEWEB)

    Stratmann, H

    1963-01-01

    Controlled climate experiments indicate that the reaction of plants is not simply proportional to the project of SO/sub 2/ concentration and exposure time, and the degree of damage inflicted increases in proportion to this product as the concentration itself increases. A determining factor is the fact that plants, even when kept in a controlled climate, undergo a diurnal cycle of sensitivity. High concentrations for a shorter time do more damage than low concentrations for a longer exposure time, indicating the existence of concentration peaks. Although most cultivated plants are resistant to night exposure, a night exposure immediately following a daylight exposure causes a multiplication of damages, as does a succession of peak concentrations. It has also been discovered that plants whose leaves are not fully developed suffer a higher degree of SO damage than those whose leaves are fully matured. In the case of deciduous trees, sensitivity increases in proportion to the development of the leaves, until full leaf maturity is reached. Older trees are more resistant to SO/sub 2/.

  11. Biophysical control of whole tree transpiration under an urban environment in Northern China

    Science.gov (United States)

    Lixin Chen; Zhiqiang Zhang; Zhandong Li; Jianwu Tang; Peter Caldwell; et al

    2011-01-01

    Urban reforestation in China has led to increasing debate about the impact of urban trees and forests on water resources. Although transpiration is the largest water flux leaving terrestrial ecosystems, little is known regarding whole tree transpiration in urban environments. In this study, we quantified urban tree transpiration at various temporal scales and examined...

  12. Characteristic Changes in Decidual Gene Expression Signature in Spontaneous Term Parturition

    Directory of Open Access Journals (Sweden)

    Haidy El-Azzamy

    2017-05-01

    Full Text Available Background The decidua has been implicated in the “terminal pathway” of human term parturition, which is characterized by the activation of pro-inflammatory pathways in gestational tissues. However, the transcriptomic changes in the decidua leading to terminal pathway activation have not been systematically explored. This study aimed to compare the decidual expression of developmental signaling and inflammation-related genes before and after spontaneous term labor in order to reveal their involvement in this process. Methods Chorioamniotic membranes were obtained from normal pregnant women who delivered at term with spontaneous labor (TIL, n = 14 or without labor (TNL, n = 15. Decidual cells were isolated from snap-frozen chorioamniotic membranes with laser microdissection. The expression of 46 genes involved in decidual development, sex steroid and prostaglandin signaling, as well as pro- and anti-inflammatory pathways, was analyzed using high-throughput quantitative real-time polymerase chain reaction (qRT-PCR. Chorioamniotic membrane sections were immunostained and then semi-quantified for five proteins, and immunoassays for three chemokines were performed on maternal plasma samples. Results The genes with the highest expression in the decidua at term gestation included insulin-like growth factor-binding protein 1 (IGFBP1, galectin-1 (LGALS1, and progestogen-associated endometrial protein (PAEP; the expression of estrogen receptor 1 (ESR1, homeobox A11 (HOXA11, interleukin 1β (IL1B, IL8, progesterone receptor membrane component 2 (PGRMC2, and prostaglandin E synthase (PTGES was higher in TIL than in TNL cases; the expression of chemokine C-C motif ligand 2 (CCL2, CCL5, LGALS1, LGALS3, and PAEP was lower in TIL than in TNL cases; immunostaining confirmed qRT-PCR data for IL-8, CCL2, galectin-1, galectin-3, and PAEP; and no correlations between the decidual gene expression and the maternal plasma protein concentrations of CCL2, CCL5, and

  13. Dormancy release and flowering time in Ziziphus jujuba Mill., a "direct flowering" fruit tree, has a facultative requirement for chilling.

    Science.gov (United States)

    Meir, Michal; Ransbotyn, Vanessa; Raveh, Eran; Barak, Simon; Tel-Zur, Noemi; Zaccai, Michele

    2016-03-15

    In deciduous fruit trees, the effect of chilling on flowering has mostly been investigated in the "indirect flowering" group, characterized by a period of rest between flower bud formation and blooming. In the present study, we explored the effects of chilling and chilling deprivation on the flowering of Ziziphus jujuba, a temperate deciduous fruit tree belonging to the "direct flowering" group, in which flower bud differentiation, blooming and fruit development occur after dormancy release, during a single growing season. Dormancy release, vegetative growth and flowering time in Z. jujuba cv. Ben-Li were assessed following several treatments of chilling. Chilling treatments quantitatively decreased the timing of vegetative bud dormancy release, thereby accelerating flowering, but had no effect on the time from dormancy release to flowering. Trees grown at a constant temperature of 25°C, without chilling, broke dormancy and flowered, indicating the facultative character of chilling in this species. We measured the expression of Z. jujuba LFY and AP1 homologues (ZjLFY and ZjAP1). Chilling decreased ZjLFY expression in dormant vegetative buds but had no effect on ZjAP1expression, which reached peak expression before dormancy release and at anthesis. In conclusion, chilling is not obligatory for dormancy release of Z. jujuba cv. Ben-Li vegetative buds. However, the exposure to chilling during dormancy does accelerate vegetative bud dormancy release and flowering. Copyright © 2016 Elsevier GmbH. All rights reserved.

  14. Analyses of the Erosive Effect of Dietary Substances and Medications on Deciduous Teeth.

    Directory of Open Access Journals (Sweden)

    Adrian Lussi

    Full Text Available This study aimed at analysing the erosive potential of 30 substances (drinks, candies, and medicaments on deciduous enamel, and analyse the associated chemical factors with enamel dissolution. We analysed the initial pH, titratable acidity (TA to pH 5.5, calcium (Ca, inorganic phosphate (Pi, and fluoride (F concentration, and degree of saturation ((pK -pIHAP, (pK -pIFAP, and (pK-pICaF2 of all substances. Then, we randomly distributed 300 specimens of human deciduous enamel into 30 groups (n = 10 for each of the substances tested. We also prepared 20 specimens of permanent enamel for the sake of comparison between the two types of teeth, and we tested them in mineral water and Coca-Cola®. In all specimens, we measured surface hardness (VHN: Vickers hardness numbers and surface reflection intensity (SRI at baseline (SH baseline and SRI baseline, after a total of 2 min (SH2 min and after 4 min (SH4 min and SRI4 min erosive challenges (60 ml of substance for 6 enamel samples; 30°C, under constant agitation at 95 rpm. There was no significant difference in SH baseline between deciduous and permanent enamel. Comparing both teeth, we observed that after the first erosive challenge with Coca-Cola®, a significantly greater hardness loss was seen in deciduous (-90.2 ± 11.3 VHN than in permanent enamel (-44.3 ± 12.2 VHN; p = 0.007, but no differences between the two types of teeth were observed after two challenges (SH4 min. After both erosive challenges, all substances except for mineral water caused a significant loss in relative surface reflectivity intensity, and most substances caused a significant loss in surface hardness. Multiple regression analyses showed that pH, TA and Ca concentration play a significant role in initial erosion of deciduous enamel. We conclude that drinks, foodstuffs and medications commonly consumed by children can cause erosion of deciduous teeth and erosion is mainly associated with pH, titratable acidity and calcium

  15. Analyses of the Erosive Effect of Dietary Substances and Medications on Deciduous Teeth.

    Science.gov (United States)

    Lussi, Adrian; Carvalho, Thiago Saads

    2015-01-01

    This study aimed at analysing the erosive potential of 30 substances (drinks, candies, and medicaments) on deciduous enamel, and analyse the associated chemical factors with enamel dissolution. We analysed the initial pH, titratable acidity (TA) to pH 5.5, calcium (Ca), inorganic phosphate (Pi), and fluoride (F) concentration, and degree of saturation ((pK -pI)HAP, (pK -pI)FAP, and (pK-pI)CaF2) of all substances. Then, we randomly distributed 300 specimens of human deciduous enamel into 30 groups (n = 10 for each of the substances tested. We also prepared 20 specimens of permanent enamel for the sake of comparison between the two types of teeth, and we tested them in mineral water and Coca-Cola®. In all specimens, we measured surface hardness (VHN: Vickers hardness numbers) and surface reflection intensity (SRI) at baseline (SH baseline and SRI baseline), after a total of 2 min (SH2 min) and after 4 min (SH4 min and SRI4 min) erosive challenges (60 ml of substance for 6 enamel samples; 30°C, under constant agitation at 95 rpm). There was no significant difference in SH baseline between deciduous and permanent enamel. Comparing both teeth, we observed that after the first erosive challenge with Coca-Cola®, a significantly greater hardness loss was seen in deciduous (-90.2 ± 11.3 VHN) than in permanent enamel (-44.3 ± 12.2 VHN; p = 0.007), but no differences between the two types of teeth were observed after two challenges (SH4 min). After both erosive challenges, all substances except for mineral water caused a significant loss in relative surface reflectivity intensity, and most substances caused a significant loss in surface hardness. Multiple regression analyses showed that pH, TA and Ca concentration play a significant role in initial erosion of deciduous enamel. We conclude that drinks, foodstuffs and medications commonly consumed by children can cause erosion of deciduous teeth and erosion is mainly associated with pH, titratable acidity and calcium

  16. Tree age dependence and within-canopy variation of leaf gas exchange and antioxidative defence in Fagus sylvatica under experimental free-air ozone exposure

    International Nuclear Information System (INIS)

    Herbinger, K.; Then, Ch.; Loew, M.; Haberer, K.; Alexous, M.; Koch, N.; Remele, K.; Heerdt, C.; Grill, D.; Rennenberg, H.; Haeberle, K.-H.; Matyssek, R.; Tausz, M.; Wieser, G.

    2005-01-01

    We characterized leaf gas exchange and antioxidative defence of two-year-old seedlings and 60-year-old trees of Fagus sylvatica exposed to ambient (1xO 3 ) or two-fold ambient (2xO 3 ) O 3 concentrations (maximum of 150 ppb) in a free-air canopy exposure system throughout the growing season. Decline in photosynthesis from sun-exposed to shaded conditions was more pronounced in adult than juvenile trees. Seedling leaves and leaves in the sun-exposed canopy had higher stomatal conductance and higher internal CO 2 concentrations relative to leaves of adult trees and leaves in shaded conditions. There was a weak overall depression of photosynthesis in the 2xO 3 variants across age classes and canopy positions. Pigment and tocopherol concentrations of leaves were significantly affected by canopy position and tree age, whereas differences between 1xO 3 and 2xO 3 regimes were not observed. Glutathione concentrations were significantly increased under 2xO 3 across both age classes and canopy levels. Seedlings differed from adult trees in relevant physiological and biochemical traits in ozone response. The water-soluble antioxidative systems responded most sensitively to 2xO 3 without regard of tree age or canopy position. - Ozone effects on leaf gas exchange and antioxidative systems of beech across tree age and canopy level were investigated in a free air exposure system

  17. Azadirachta indica A. Juss. (English: Margosa or Neem tree; Hindi ...

    Indian Academy of Sciences (India)

    (English: Margosa or Neem tree; Hindi: Neem) ofMeliaceae a large evergreen tree with spreading crown and brownish bark is either pLanted or se(f-sown. Leaves are compound and the LeafLets are somewhat oblique with toothed margin. Flowers are small and white and borne on branched inflorescence. Fruit is about ...

  18. Ascorbic Acid Alleviates Water Stress in Young Peach Trees and Improves Their Performance after Rewatering.

    Science.gov (United States)

    Penella, Consuelo; Calatayud, Ángeles; Melgar, Juan C

    2017-01-01

    Exogenous application of biochemicals has been found to improve water stress tolerance in herbaceous crops but there are limited studies on deciduous fruit trees. The goal of this research was to study if ascorbic acid applications could improve physiological mechanisms associated with water stress tolerance in young fruit trees. Ascorbic acid was foliarly applied at a concentration of 250 ppm to water-stressed and well-watered peach trees (control) of two cultivars ('Scarletprince' and 'CaroTiger'). Trees received either one or two applications, and 1 week after the second application all trees were rewatered to field capacity. Upon rewatering, CO 2 assimilation and stomatal conductance of water-stressed 'Scarletprince' trees sprayed with ascorbic acid (one or two applications) were similar to those of well-irrigated trees, but water-stressed trees that had not received ascorbic acid did not recover photosynthetical functions. Also, water status in sprayed water-stressed 'Scarletprince' trees was improved to values similar to control trees. On the other hand, water-stressed 'CaroTiger' trees needed two applications of ascorbic acid to reach values of CO 2 assimilation similar to control trees but these applications did not improve their water status. In general terms, different response mechanisms to cope with water stress in presence of ascorbic acid were found in each cultivar, with 'Scarletprince' trees preferentially using proline as compatible solute and 'CaroTiger' trees relying on stomatal regulation. The application of ascorbic acid reduced cell membrane damage and increased catalase activity in water-stressed trees of both cultivars. These results suggest that foliar applications of ascorbic acid could be used as a management practice for improving water stress tolerance of young trees under suboptimal water regimes.

  19. Acceleration of the glycolytic flux by steroid receptor coactivator-2 is essential for endometrial decidualization.

    Directory of Open Access Journals (Sweden)

    Ramakrishna Kommagani

    2013-10-01

    Full Text Available Early embryo miscarriage is linked to inadequate endometrial decidualization, a cellular transformation process that enables deep blastocyst invasion into the maternal compartment. Although much of the cellular events that underpin endometrial stromal cell (ESC decidualization are well recognized, the individual gene(s and molecular pathways that drive the initiation and progression of this process remain elusive. Using a genetic mouse model and a primary human ESC culture model, we demonstrate that steroid receptor coactivator-2 (SRC-2 is indispensable for rapid steroid hormone-dependent proliferation of ESCs, a critical cell-division step which precedes ESC terminal differentiation into decidual cells. We reveal that SRC-2 is required for increasing the glycolytic flux in human ESCs, which enables rapid proliferation to occur during the early stages of the decidualization program. Specifically, SRC-2 increases the glycolytic flux through induction of 6-phosphofructo-2-kinase/fructose-2, 6-bisphosphatase 3 (PFKFB3, a major rate-limiting glycolytic enzyme. Similarly, acute treatment of mice with a small molecule inhibitor of PFKFB3 significantly suppressed the ability of these animals to exhibit an endometrial decidual response. Together, these data strongly support a conserved mechanism of action by which SRC-2 accelerates the glycolytic flux through PFKFB3 induction to provide the necessary bioenergy and biomass to meet the demands of a high proliferation rate observed in ESCs prior to their differentiation into decidual cells. Because deregulation of endometrial SRC-2 expression has been associated with common gynecological disorders of reproductive-age women, this signaling pathway, involving SRC-2 and PFKFB3, promises to offer new clinical approaches in the diagnosis and/or treatment of a non-receptive uterus in patients presenting idiopathic infertility, recurrent early pregnancy loss, or increased time to pregnancy.

  20. Trees of Our National Forests.

    Science.gov (United States)

    Forest Service (USDA), Washington, DC.

    Presented is a description of the creation of the National Forests system, how trees grow, managing the National Forests, types of management systems, and managing for multiple use, including wildlife, water, recreation and other uses. Included are: (1) photographs; (2) line drawings of typical leaves, cones, flowers, and seeds; and (3)…

  1. Arthropod but not bird predation in ethiopian homegardens is higher in tree-poor than in tree-rich landscapes.

    Science.gov (United States)

    Lemessa, Debissa; Hambäck, Peter A; Hylander, Kristoffer

    2015-01-01

    Bird and arthropod predation is often associated with natural pest control in agricultural landscapes, but the rates of predation may vary with the amount of tree cover or other environmental factors. We examined bird and arthropod predation in three tree-rich and three tree-poor landscapes across southwestern Ethiopia. Within each landscape we selected three tree-rich and three tree-poor homegardens in which we recorded the number of tree species and tree stems within 100 × 100 m surrounding the central house. To estimate predation rates, we attached plasticine caterpillars on leaves of two coffee and two avocado shrubs in each homegarden, and recorded the number of attacked caterpillars for 7-9 consecutive weeks. The overall mean daily predation rate was 1.45% for birds and 1.60% for arthropods. The rates of arthropod predation varied among landscapes and were higher in tree-poor landscapes. There was no such difference for birds. Within landscapes, predation rates from birds and arthropods did not vary between tree-rich and tree-poor homegardens in either tree-rich or tree-poor landscapes. The most surprising result was the lack of response by birds to tree cover at either spatial scale. Our results suggest that in tree-poor landscapes there are still enough non-crop habitats to support predatory arthropods and birds to deliver strong top-down effect on crop pests.

  2. Arthropod but not bird predation in ethiopian homegardens is higher in tree-poor than in tree-rich landscapes.

    Directory of Open Access Journals (Sweden)

    Debissa Lemessa

    Full Text Available Bird and arthropod predation is often associated with natural pest control in agricultural landscapes, but the rates of predation may vary with the amount of tree cover or other environmental factors. We examined bird and arthropod predation in three tree-rich and three tree-poor landscapes across southwestern Ethiopia. Within each landscape we selected three tree-rich and three tree-poor homegardens in which we recorded the number of tree species and tree stems within 100 × 100 m surrounding the central house. To estimate predation rates, we attached plasticine caterpillars on leaves of two coffee and two avocado shrubs in each homegarden, and recorded the number of attacked caterpillars for 7-9 consecutive weeks. The overall mean daily predation rate was 1.45% for birds and 1.60% for arthropods. The rates of arthropod predation varied among landscapes and were higher in tree-poor landscapes. There was no such difference for birds. Within landscapes, predation rates from birds and arthropods did not vary between tree-rich and tree-poor homegardens in either tree-rich or tree-poor landscapes. The most surprising result was the lack of response by birds to tree cover at either spatial scale. Our results suggest that in tree-poor landscapes there are still enough non-crop habitats to support predatory arthropods and birds to deliver strong top-down effect on crop pests.

  3. Exploring Relationships among Tree-Ring Growth, Climate Variability, and Seasonal Leaf Activity on Varying Timescales and Spatial Resolutions

    OpenAIRE

    Bhuyan, Upasana;Zang, Christian;Vicente-Serrano, Sergio;Menzel, Annette

    2018-01-01

    In the first section of this study, we explored the relationship between ring width index (RWI) and normalized difference vegetation index (NDVI) time series on varying timescales and spatial resolutions, hypothesizing positive associations between RWI and current and previous- year NDVI at 69 forest sites scattered in the Northern Hemisphere. We noted that the relationship between RWI and NDVI varies over space and between tree types (deciduous versus coniferous), bioclimatic zones, cumulati...

  4. Exploring Relationships among Tree-Ring Growth, Climate Variability, and Seasonal Leaf Activity on Varying Timescales and Spatial Resolutions

    OpenAIRE

    Upasana Bhuyan; Christian Zang; Sergio M. Vicente-Serrano; Annette Menzel

    2017-01-01

    In the first section of this study, we explored the relationship between ring width index (RWI) and normalized difference vegetation index (NDVI) time series on varying timescales and spatial resolutions, hypothesizing positive associations between RWI and current and previous- year NDVI at 69 forest sites scattered in the Northern Hemisphere. We noted that the relationship between RWI and NDVI varies over space and between tree types (deciduous versus coniferous), bioclimatic zones, cumulati...

  5. A practical O(n log2 n) time algorithm for computing the triplet distance on binary trees

    DEFF Research Database (Denmark)

    Sand, Andreas; Pedersen, Christian Nørgaard Storm; Mailund, Thomas

    2013-01-01

    rooted binary trees in time O (n log2 n). The algorithm is related to an algorithm for computing the quartet distance between two unrooted binary trees in time O (n log n). While the quartet distance algorithm has a very severe overhead in the asymptotic time complexity that makes it impractical compared......The triplet distance is a distance measure that compares two rooted trees on the same set of leaves by enumerating all sub-sets of three leaves and counting how often the induced topologies of the tree are equal or different. We present an algorithm that computes the triplet distance between two...

  6. Changes in conifer and deciduous forest foliar and forest floor chemistry and basal area tree growth across a nitrogen (N) deposition gradient in the northeastern US

    Science.gov (United States)

    Johnny L. Boggs; Steven G. McNulty; Linda H. Pardo

    2007-01-01

    We evaluated foliar and forest floor chemistry across a gradient of N deposition in the Northeast at 11 red spruce (Picea rubens Sarg.) sites in 1987/1988 and foliar and forest floor chemistry and basal area growth at six paired spruce and deciduous sites in 1999. The six red spruce plots were a subset of the original 1987/1988 spruce sites. In 1999...

  7. Spatial pattern of tree diversity and evenness across forest types in Majella National Park, Italy

    Directory of Open Access Journals (Sweden)

    Mohammad Redowan

    2015-09-01

    Full Text Available Background Estimation of tree diversity at broader scale is important for conservation planning. Tree diversity should be measured and understood in terms of diversity and evenness, two integral components to describe the structure of a biological community. Variation of the tree diversity and evenness with elevation, topographic relief, aspect, terrain shape, slope, soil nutrient, solar radiation etc. are well documented. Methods Present study explores the variation of tree diversity (measured as Shannon diversity and evenness indices of Majella National Park, Italy with five available forest types namely evergreen oak woods, deciduous oak woods, black/aleppo pine stands, hop-hornbeam forest and beech forest, using satellite, environmental and field data. Results Hop-hornbeam forest was found to be most diverse and even while evergreen Oak woods was the lowest diverse and even. Diversity and evenness of forest types were concurrent to each other i.e. forest type which was more diverse was also more even. As a broad pattern, majority portion of the study area belonged to medium diversity and high evenness class. Conclusions Satellite images and other GIS data proved useful tools in monitoring variation of tree diversity and evenness across various forest types. Present study findings may have implications in prioritizing conservation zones of high tree diversity at Majella.

  8. Essential oil alloaromadendrene from mixed-type Cinnamomum osmophloeum leaves prolongs the lifespan in Caenorhabditis elegans.

    Science.gov (United States)

    Yu, Chan-Wei; Li, Wen-Hsuan; Hsu, Fu-Lan; Yen, Pei-Ling; Chang, Shang-Tzen; Liao, Vivian Hsiu-Chuan

    2014-07-02

    Cinnamomum osmophloeum Kaneh. is an indigenous tree species in Taiwan. The present study investigates phytochemical characteristics, antioxidant activities, and longevity of the essential oils from the leaves of the mixed-type C. osmophloeum tree. We demonstrate that the essential oils from leaves of mixed-type C. osmophloeum exerted in vivo antioxidant activities on Caenorhabditis elegans. In addition, minor (alloaromadendrene, 5.0%) but not major chemical components from the leaves of mixed-type C. osmophloeum have a key role against juglone-induced oxidative stress in C. elegans. Additionally, alloaromadendrene not only acts protective against oxidative stress but also prolongs the lifespan of C. elegans. Moreover, mechanistic studies show that DAF-16 is required for alloaromadendrene-mediated oxidative stress resistance and longevity in C. elegans. The results in the present study indicate that the leaves of mixed-type C. osmophloeum and essential oil alloaromadendrene have the potential for use as a source for antioxidants or treatments to delay aging.

  9. Imaging in gynecological disease. 10: Clinical and ultrasound characteristics of decidualized endometriomas surgically removed during pregnancy.

    Science.gov (United States)

    Mascilini, F; Moruzzi, C; Giansiracusa, C; Guastafierro, F; Savelli, L; De Meis, L; Epstein, E; Timor-Tritsch, I E; Mailath-Pokorny, M; Ercoli, A; Exacoustos, C; Benacerraf, B R; Valentin, L; Testa, A C

    2014-09-01

    To describe the clinical history and ultrasound findings in women with decidualized endometriomas surgically removed during pregnancy. In this retrospective study, women with a histological diagnosis of decidualized endometrioma during pregnancy who had undergone preoperative ultrasound examination were identified from the databases of seven ultrasound centers. The ultrasound appearance of the tumors was described on the basis of ultrasound images, ultrasound reports and research protocols (when applicable) by one author from each center using the terms and definitions of the International Ovarian Tumor Analysis (IOTA) group. In addition, two authors reviewed together available digital ultrasound images and used pattern recognition to describe the typical ultrasound appearance of decidualized endometriomas. Eighteen eligible women were identified. Median age was 34 (range, 20-43) years. Median gestational age at surgical removal of the decidualized endometrioma was 18 (range, 11-41) weeks. Seventeen women (94%) were asymptomatic and one presented with pelvic pain. In three of the 18 women an ultrasound diagnosis of endometrioma had been made before pregnancy. The original ultrasound examiner was uncertain whether the mass was benign or malignant in 10 (56%) women and suggested a diagnosis of benignity in nine (50%) women, borderline in eight women (44%), and invasive malignancy in one (6%) woman. Seventeen decidualized endometriomas contained a papillary projection, and in 16 of these at least one of the papillary projections was vascularized at power or color Doppler examination. The number of cyst locules varied between one (n = 11) and four. No woman had ascites. When using pattern recognition, most decidualized endometriomas (14/17, 82%) were described as manifesting vascularized rounded papillary projections with a smooth contour in an ovarian cyst with one or a few cyst locules and ground-glass or low-level echogenicity of the cyst fluid. Rounded vascularized

  10. New flux based dose–response relationships for ozone for European forest tree species

    International Nuclear Information System (INIS)

    Büker, P.; Feng, Z.; Uddling, J.; Briolat, A.; Alonso, R.; Braun, S.; Elvira, S.; Gerosa, G.; Karlsson, P.E.; Le Thiec, D.

    2015-01-01

    To derive O 3 dose–response relationships (DRR) for five European forest trees species and broadleaf deciduous and needleleaf tree plant functional types (PFTs), phytotoxic O 3 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 O 3 flux concept and represents a step forward in predicting O 3 damage to forests in a spatially and temporally varying climate. - Highlights: • We present new ozone flux based dose–response relationships for European trees. • The model-based study accounted for the soil water effect on stomatal flux. • Different statistically derived ozone flux thresholds were applied. • Climate region specific parameterisation often outperformed simplified parameterisation. • Findings could help redefining critical levels for ozone effects on trees. - New stomatal flux based ozone dose–response relationships for tree species are derived for the regional risk assessment of ozone effects on European forest ecosystems.

  11. Longevity of guard cell chloroplasts in falling leaves: implication for stomatal function and cellular aging.

    Science.gov (United States)

    Zeiger, E; Schwartz, A

    1982-11-12

    Guard cell chloroplasts in senescing leaves from 12 species of perennial trees and three species of annual plants survived considerably longer than their mesophyll counterparts. In Ginkgo biloba, stomata from yellow leaves opened during the day and closed at night; guard cell chloroplasts from these leaves showed fluorescence transients associated with electron transport and photophosphorylation. These findings indicate that guard cell chloroplasts are highly conserved throughout the life-span of the leaf and that leaves retain stomatal control during senescence.

  12. Tracing {sup 13}C reveals the below ground connection between trees and fungi

    Energy Technology Data Exchange (ETDEWEB)

    Siegwolf, R.T.W.; Steinmann, K.; Saurer, M.; Koerner, Ch.

    2003-03-01

    Freshly assimilated atmospheric CO{sub 2} is transferred as sugars from the leaves into the whole organism. Since mycorrhiza fungi and tree roots are in an intensive symbiosis, the fungi provide important information about the tree internal carbon distribution. (author)

  13. Physiological Adjustments of Leaf Respiration to Atmospheric Warming in Betula alleghaniensis and Quercus rubra

    Energy Technology Data Exchange (ETDEWEB)

    Vollmar, A.; Gunderson, C.

    2006-01-01

    Global air temperatures are predicted to rise 1° to 4.5° Celsius by the year 2100. This climatic change is expected to have a great effect on the succession and migration of temperate deciduous forest species. Most physiologically based models of forest response to climatic change focus on the ecosystems as a whole instead of on individual tree species, assuming that the effects of warming on respiration are generally the same for each species, and that processes can not adjust to a changing climate. Experimental data suggest that physiological adjustments are possible, but there is a lack of data in deciduous species. In order to correctly model the effects of climate change on temperate species, species-specific respiration acclimation (adjustment) to rising temperatures is being determined in this experiment. Two temperate deciduous tree species Betula alleghaniensis (BA) and Quercus rubra (QR) were grown over a span of four years in open-top chambers and subjected to two different temperature treatments; ambient and ambient plus 4° Celsius (E4). Between 0530 hours and 1100 hours, respiration was measured over a range of leaf temperatures on several comparable, fully expanded leaves in each treatment. Circular punches were taken from the leaves and dried at 60°C to determine leaf mass per area (LMA). Respiration rates at a common temperature decreased by 15-18% in both species, and the entire resperation versus temperature curve shifted by at least 4°C, indicating a large degree of physiological acclimation. Foliar mass per area decreased with increasing growth temperature for both species. It can be concluded that there is a relationship between leaf respiration and foliar mass as it relates to respiratory acclimation, and that these two species had similar patterns of adjustment to warming.

  14. Variability of the soil seed banks in the natural deciduous forest in the Białowieża National Park

    Directory of Open Access Journals (Sweden)

    Małgorzata Jankowska-Błaszczuk

    2014-01-01

    Full Text Available Using the germination method, the species diversity, density of the soil seed bank and its relation to cover vegetation in a natural deciduous forest with primary and secondary tree stand were compared. It was found that the mean density and species composition of the soil seed bank in the forest with secondary tree stand that has spontaneously been overgrown over the last 90 years after clear-cutting does not differ from the soil seed bank derived from primeval forest (3167M-2 vs. 3827m-2. In both stands there were 46 species altogether and 36 were common and seed banks were dominated by herbs. The most abundant in this group were: Urtica dioica, Chrysosplenium alternifolium, Geranium robertianum, Oxalis acetosella. In both cases it was found that the species structure of the herb layer was similar to that of the seed bank in about 70%. The seed banks of species absent from the herb layer or present there only sporadically were much more abundant. The seedlings of these species constituted more than one third of all seedlings that emerged in the samples from the secondary tree stand and only 5% those from the primary one. The analysis of seed bank in heavily rooted places under primary and secondary tree stands showed that in places with a totally distroyed herb layer the density of the soil seed bank in primeval forest was three times lower than in places with fully developed herb layer structure (102.60±22.61 vs. 307.0±206.5 per sample. This difference under secondary tree stand turned out to be much lower (415.8±137.8 vs. 358.2±126.0 per sample.

  15. Trees as bioindicator of heavy metal pollution in three European cities

    Energy Technology Data Exchange (ETDEWEB)

    Sawidis, T. [Department of Botany, University of Thessaloniki, 54124 Thessaloniki (Greece); Breuste, J., E-mail: juergen.breuste@sbg.ac.at [Department of Geography and Geology, University of Salzburg, 5010 Salzburg (Austria); Mitrovic, M.; Pavlovic, P. [Department of Ecology, Institute for Biological Research ' Sinisa Stankovic' , University of Belgrade, Bulevar despota Stefana 142, 11060 Belgrade (Serbia); Tsigaridas, K. [Department of Botany, University of Thessaloniki, 54124 Thessaloniki (Greece)

    2011-12-15

    Concentrations of four heavy metals were determined in tree leaves and bark collected from polluted and non-polluted areas of three European cities (Salzburg, Belgrade and Thessaloniki) for a comparative study. Platanus orientalis L. and Pinus nigra Arn., widespread in urban northern and southern Europe, were tested for their suitability for air quality biomonitoring. Leaves and barks were collected uniformly of an initial quantity of about 30 g of each sample. Analysis was accomplished by electrothermal atomic absorption spectrometry after total digestion. Site-dependent variations were found with the highest concentration level measured in Belgrade, followed by Thessaloniki and Salzburg. A higher accumulation of heavy metals was found in bark compared to leaves. Pine tree bark, accumulating higher concentrations of trace metals compared to plane tree bark, shows a higher efficiency as bioindicator for urban pollution. Both indicator species are suitable for comparative studies on bioindication of urban air pollution. - Highlights: > Oriental plane and Austrian pine are suitable for comparative urban air quality biomonitoring of heavy metal pollution. > Pine tree is excellently suitable as urban bioindicator as it accumulates high concentrations of trace metals. > The highest heavy metal pollution was found in Belgrade followed by Thessaloniki and Salzburg. - Oriental plane (Platanus orientalis L.) and Austrian pine (Pinus nigra Arn.), widespread in urban northern and southern Europe, are suitable for comparative biomonitoring of urban air pollution.

  16. Trees as bioindicator of heavy metal pollution in three European cities

    International Nuclear Information System (INIS)

    Sawidis, T.; Breuste, J.; Mitrovic, M.; Pavlovic, P.; Tsigaridas, K.

    2011-01-01

    Concentrations of four heavy metals were determined in tree leaves and bark collected from polluted and non-polluted areas of three European cities (Salzburg, Belgrade and Thessaloniki) for a comparative study. Platanus orientalis L. and Pinus nigra Arn., widespread in urban northern and southern Europe, were tested for their suitability for air quality biomonitoring. Leaves and barks were collected uniformly of an initial quantity of about 30 g of each sample. Analysis was accomplished by electrothermal atomic absorption spectrometry after total digestion. Site-dependent variations were found with the highest concentration level measured in Belgrade, followed by Thessaloniki and Salzburg. A higher accumulation of heavy metals was found in bark compared to leaves. Pine tree bark, accumulating higher concentrations of trace metals compared to plane tree bark, shows a higher efficiency as bioindicator for urban pollution. Both indicator species are suitable for comparative studies on bioindication of urban air pollution. - Highlights: → Oriental plane and Austrian pine are suitable for comparative urban air quality biomonitoring of heavy metal pollution. → Pine tree is excellently suitable as urban bioindicator as it accumulates high concentrations of trace metals. → The highest heavy metal pollution was found in Belgrade followed by Thessaloniki and Salzburg. - Oriental plane (Platanus orientalis L.) and Austrian pine (Pinus nigra Arn.), widespread in urban northern and southern Europe, are suitable for comparative biomonitoring of urban air pollution.

  17. The Role of Native Tree Species on Leaf Breakdown Dynamics of the Invasive Tree of Heaven ( Ailanthus altissima) in an Urban Stream

    Science.gov (United States)

    Swan, C.; Healey, B.

    2005-05-01

    Anthropogenic disturbance of ecosystem processes is increasingly being explored in urban settings. One profound impact is the striking increase in the distribution of invasive plant species. For example, Tree of Heaven (Ailanthus altissima, TOH), introduced into the U.S. from Asia in 1784, is a successful colonist of recently deforested habitats. As a result, remnant patches in urban ecosystems have become overrun with this tree species, excluding native species via fast growth and allelopathy. While suffering from human-induced degradation, urban streams still support food webs that function to process riparian-derived organic matter (e.g., leaves, wood). The purpose of this study was to (1) estimate leaf litter breakdown of native tree leaves and those of TOH in an urban stream, (2) study the detritivore feeding rate of the same leaf species, and (3) determine if increasing native species richness of leaf litter can alter breakdown of TOH leaves. Field manipulations of leaf pack composition were done in a highly urbanized stream (>30% upstream urban land use) in Baltimore County, Maryland, USA. This was complimented by a series of laboratory feeding experiments employing similar leaf treatments and local shredding invertebrate taxa. Breakdown of TOH alone was extremely rapid, significantly exceeding that of all native tree species employed. Furthermore, mixing TOH with native tree species, red maple and white oak, substantially reduced TOH decay compared to decay of TOH alone. However, supporting laboratory studies showed that TOH was a preferred resource by shredding invertebrates over all native species. Subsequent analysis of the structural integrity of all leaf species revealed that TOH was the least resistant to force, possibly explaining the counterintuitive decrease of TOH decay in mixtures. We interpret this as meaning the stream invertebrates, while preferring to consume TOH, appeared not to influence TOH decay in mixtures with native species. Instead

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

    Science.gov (United States)

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

    2017-02-01

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

  19. Rituals, ceremonies and customs related to sacred trees with a special reference to the Middle East

    Directory of Open Access Journals (Sweden)

    Dafni Amots

    2007-07-01

    Full Text Available Abstract Tree worship is very common worldwide. This field study surveys the ceremonies and customs related to sacred trees in present-day Israel; it includes the results of interviews with 98 informants in thirty-one Arab, Bedouin, and Druze villages in the Galilee. The main results are: 1. Sacred trees were treated as another kind of sacred entity with all their metaphysical as well as physical manifestations. 2. There is not even one ceremony or custom that is peculiar only to a sacred tree and is not performed in other sacred places (such as a saint's grave or a mosque. 3. Few customs, such as: quarrel settling (= Sulkha, leaving objects to absorb the divine blessing and leaving objects for charity seem to be characteristic of this region, only. 4. In modern times, sacred trees were never recorded, in Israel, as centres for official religious ceremonies including sacrifices, nor as places for the performing of rites of passage. 5. There is some variation among the different ethnic groups: Kissing trees and worshipping them is more common among the Druze although carrying out burials under the tree, leaving water and rain-making ceremonies under them have not been recorded in this group. Passing judgments under the tree is more typical of the Bedouin in which the sacred trees were commonly used as a public social centre. Most of the customs surveyed here are known from other parts of the world. The differences between Muslims and Druze are related to the latter's belief in the transmigration of souls.

  20. Characteristics of element composition of aerosols adsorbed on leaves by radioactivation analysis and their effects on plants

    International Nuclear Information System (INIS)

    Takamatsu, Takejiro; Koshikawa, Masami; Sase, Hiroyuki; Masuzawa, Toshiyuki; Kawashima, Munetsugu; Takada, Jitsuya; Matsushita, Rokuji

    1999-01-01

    Aerosol deposits on leaves of various trees, especially cedar in different regions of Japan were collected to characterize the elemental composition using neutron activation analysis, ICP-AES, etc. and also investigate the effects of deposit aerosols on plants and the efficacy as an indicator for air pollution. Compared with the elemental composition of the soil, Se, Cr, Au, Br, As, Sb, Ag, etc. were more abundant in aerosols on cedar leaves. Especially, Sb is thought to be mostly derived from combustion of fossil fuels (exhaust gas from cars, etc.). Since Sb was accumulated on leaves at high levels and the analytical precision for Sb by neutron radioactivation was very high, the element was thought useful as an indicator for air pollution. If the amounts of Sb on the leaves of cedar and pine trees, which are widely distributed in Japan are determined, the degrees of pollution in all regions of Japan would be determined. In cedar trees of Saitama Prefecture where the deposit amounts of aerosols were comparatively larger, 42% of stoma was covered with the deposits, resulting that the rate of cuticular transpiration was increased and the amounts of basic elements leached from the leave surface was also increased. Thus, it was suggested that these changes might be the cause of recent declining of cedars in Japanese urban regions. (M.N.)