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Sample records for deciduous broad-leaved forest

  1. [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.

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

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    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

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

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    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.

  4. 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.

  5. 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.

  6. Forest litter stocks in Korean pine-broad-leaved forests of the southern Sikhote Alin

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    A. V. Ivanov

    2015-10-01

    Full Text Available The article presents the data on the forest litter of the Korean pine-broad-leaved forests of the South of Primorsky krai. The focus of the research is plantations dominated by Korean pine; areas of the main tree species with ages of 50, 80, 130 and 200 years were selected. The dynamics of the forest litter stock in the pine and broadleaved forests of different ages according to the measurement results for the season in 2014 is stated. In the studied plantation, the forest litter stock varies between 9.7–20.3 t ha-1. The greatest value of the forest litter stock is recorded in old-growth cedar forest (200 years. Relatively high power and the stock of litter are typical for young Korean pine forest that can explain the lower speed of the litter properties change against the dynamics of taxation indicators of the forest stand. The difference between the amount of the litter in the 200-year-old and remaining pine trees are statistically significant at p = 0.05. The dependence of the litter power on the age is not revealed. The coefficient of the forest litter decomposition ranges from 2.55–10.60 that characterizes the high speed of its rotting. The highest coefficient of the litter decomposition has an old-growing pine forest. The schedule of seasonal humidity fluctuations of the forest litter on the chosen plot is made; with increasing cedar forest age, the volumetric moisture content of the forest litter increases; volumetric moisture content on the plots remain relatively unchanged during the season. The area of the Korean pine forests of Primorsky State Academy of Agriculture is 6835 ha. The amount of carbon stock in the forest litter is 38.7 thousand tons C. in this area, while the system of regional assessment of the forest carbon balance estimates this index as 24.3 tons С. The data obtained can be used to adjust the coefficients of regional assessment of the forest carbon balance for cedar forests of Primorsky krai.

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

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    Yang Lu

    2016-01-01

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

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

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

    2013-01-01

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

  9. [Microelement contents of litter, soil fauna and soil in Pinus koraiensis and broad-leaved mixed forest].

    Science.gov (United States)

    Yin, Xiu-qin; Li, Jin-xia; Dong, Wei-hua

    2007-02-01

    The analysis on the Mn, Zn and Cu contents of litter, soil fauna and soil in Pinus korazenszis and broad-leaved mixed forest in Liangshui Natural Reserve of Xiaoxing' an Mountains showed that the test microelement contents in the litter, soil fauna and soil all followed the sequence of Mn > Zn > Cu, but varied with these environmental components, being in the sequence of soil > litter > soil fauna for Mn, soil fauna > litter and soil for Zn, and soil fauna > soil > litter for Cu. The change range of test microelement contents in litter was larger in broad-leaved forest than in coniferous forest. Different soil fauna differed in their microelement-enrichment capability, e. g. , earthworm, centipede, diplopod had the highest content of Mn, Zn and Cu, respectively. The contents of test microelements in soil fauna had significant correlations with their environmental background values, litter decomposition rate, food habit of soil fauna, and its absorbing selectivity and enrichment to microelements. The microelements contained in 5-20 cm soil layer were more than those in 0-5 cm soil layer, and their dynamics differed in various soil layers.

  10. Retention of available P in acid soils of tropical and subtropical evergreen broad-leaved forests

    Institute of Scientific and Technical Information of China (English)

    CHEN Jianhui; ZOU Xiaoming; YANG Xiaodong

    2007-01-01

    Precipitation of mineral phosphate is often recognized as a factor of limiting the availability of P in acidic soils of tropical and subtropical forests.For this paper,we studied the extractable P pools and their transformation rates in soils of a tropical evergreen forest at Xishuangbanna and a subtropical montane wet forest at the Ailao Mountains in order to understand the biogeochemical processes regulating P availability in acidic soils.The two forests differ in forest humus layer;it is deep in the Ailao forest while little is present in the Xishuangbanna forest.The extractable P pools by resin and sodium-bicarbonate decreased when soil organic carbon content was reduced.The lowest levels of extractable P pools occurred in the surface (0-10 era) mineral soils of the Xishuangbanna forest.However,microbial P in the mineral soil of the Xishuangbauna forest was twice that in the Ailao forest.Potential rates of microbial P immobilization were greater than those of organic P mineralization in mineral soils for both forests.We suggest that microbial P immobilization plays an essential role in avoiding mineral P precipitation and retaining available P of plant in tropical acidic soils,whereas both floor mass accumulation and microbial P immobilization function benefit retaining plant available P in subtropical montane wet forests.

  11. Behavior of 7Be and 210Pb deposited via rainwater on a coniferous forest, a broad-leaved forest, and grassland

    International Nuclear Information System (INIS)

    Osaki, S.; Sugihara, S.; Maeda, Y.; Osaki, T.

    2007-01-01

    Fall water, stem flow water and falling litter in a coniferous forest (C. japonica) and a broad-leaved forest (L. edulis), and rainwater on a grassland near the forests were collected, and their 7 Be and 210 Pb contents were measured. The average residence times of 7 Be and 210 Pb in the forest crowns were calculated from the balances of their radionuclides, those in the forest crown of C. japonica were 88 days for 7 Be and 9.2 years for 210 Pb, and those in the forest crown of L. edulis were 52 days and <1 year, respectively. (author)

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

    OpenAIRE

    N. K. Kozhevnikova; T. N. Lutsenko; A. G. Boldeskul; S. Yu. Lupakov; V. V. Shamov

    2017-01-01

    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 composit...

  13. Exploring Conservation Options in the Broad-Leaved Korean Pine Mixed Forest of the Changbai Mountain Region

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    Lin Ma

    2015-05-01

    Full Text Available The broad-leaved Korean pine (Pinus koraiensis mixed forest (BKPF is one of the most biodiverse zonal communities in the northern temperate zone. Changbai Mountain in northeastern China contains one of the largest BKPFs in the region. The government of China has established a network of 23 nature reserves to protect the BKPF and the species that depend on it for habitat, including the endangered Siberian tiger (Panthera tigris altaica. This study used the conservation planning software C-Plan to calculate the irreplaceability value of each unit to assess how efficiently and comprehensively the existing conservation network supports biodiversity and to identify gap areas that, if integrated into the network, would expand its protection capability. Results show a number of high-conservation-value planning units concentrated along certain ridges. The existing conservation network is structured such that the habitats of only 24 species (out of a total of 75 achieve established conservation targets. Of the other 51 species, 20 achieve less than 50% of their conservation targets. However, expanding the network to include high-conservation-value gap areas could achieve conservation targets for 64 species and could provide different degrees of protection to the other 11 species. Using C-Plan software can guide decision-making to expand the conservation network in this most precious of mountainous ecological zones.

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

    Science.gov (United States)

    Xiaojun Du; Qinfeng Guo; Xianming Gao; Keping Na

    2007-01-01

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

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

    Science.gov (United States)

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

    2004-10-01

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

  16. [Dynamics of total organic carbon (TOC) in hydrological processes in coniferous and broad-leaved mixed forest of Dinghushan].

    Science.gov (United States)

    Yin, Guangcai; Zhou, Guoyi; Zhang, Deqiang; Wang, Xu; Chu, Guowei; Liu, Yan

    2005-09-01

    The total flux and concentration of total organic carbon (TOC) in hydrological processes in coniferous and broad-leaved mixed forest of Dinghushan were measured from July 2002 to July 2003. The results showed that the TOC input by precipitation was 41.80 kg x hm(-2) x yr(-1), while its output by surface runoff and groundwater (soil solution at 50 cm depth) was 17.54 and 1.80 kg x hm(-2) x yr(-1), respectively. The difference between input and output was 22.46 kg x hm(-2) x yr(-1), indicating that the ecosystem TOC was in positive balance. The monthly variation of TOC flux in hydrological processes was very similar to that in precipitation. The mean TOC concentration in precipitation was 3.64 mg x L(-1), while that in throughfall and stemflow increased 6.10 and 7.39 times after rain passed through the tree canopies and barks. The mean TOC concentration in surface runoff and in soil solution at 25 and 50 cm depths was 12.72, 7.905 and 3.06 mg x L(-1), respectively. The monthly TOC concentration in throughfall and stemflow had a similar changing tendency, showing an increase at the beginning of growth season (March), a decrease after September, and a little increase in December. The TOC concentration in runoff was much higher during high precipitation months. No obvious monthly variation was observed in soil solution TOC concentration (25 and 50 cm below the surface). Stemflow TOC concentration differed greatly between different tree species. The TOC concentration in precipitation, throughfall, and soil solution (25 and 50 cm depths) decreased with increasing precipitation, and no significant relationship existed between the TOC concentrations in stemflow, surface runoff and precipitation. The TOC concentrations in the hydrological processes fluctuated with precipitation intensity, except for that in stemflow and soil solutions.

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

    International Nuclear Information System (INIS)

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

    2018-01-01

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

  18. A climate change-induced threat to the ecological resilience of a subtropical monsoon evergreen broad-leaved forest in Southern China.

    Science.gov (United States)

    Zhou, Guoyi; Peng, Changhui; Li, Yuelin; Liu, Shizhong; Zhang, Qianmei; Tang, Xuli; Liu, Juxiu; Yan, Junhua; Zhang, Deqiang; Chu, Guowei

    2013-04-01

    Recent studies have suggested that tropical forests may not be resilient against climate change in the long term, primarily owing to predicted reductions in rainfall and forest productivity, increased tree mortality, and declining forest biomass carbon sinks. These changes will be caused by drought-induced water stress and ecosystem disturbances. Several recent studies have reported that climate change has increased tree mortality in temperate and boreal forests, or both mortality and recruitment rates in tropical forests. However, no study has yet examined these changes in the subtropical forests that account for the majority of China's forested land. In this study, we describe how the monsoon evergreen broad-leaved forest has responded to global warming and drought stress using 32 years of data from forest observation plots. Due to an imbalance in mortality and recruitment, and changes in diameter growth rates between larger and smaller trees and among different functional groups, the average DBH of trees and forest biomass have decreased. Sap flow measurements also showed that larger trees were more stressed than smaller trees by the warming and drying environment. As a result, the monsoon evergreen broad-leaved forest community is undergoing a transition from a forest dominated by a cohort of fewer and larger individuals to a forest dominated by a cohort of more and smaller individuals, with a different species composition, suggesting that subtropical forests are threatened by their lack of resilience against long-term climate change. © 2012 Blackwell Publishing Ltd.

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

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    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.

  20. [Effects of selective cutting on soil phosphorus forms and availability in Korean pine broad-leaved forest in Xiaoxing'an Mountains of China.

    Science.gov (United States)

    Zhang, Xin; Gu, Hui Yan; Chen, Xiang Wei

    2018-02-01

    In order to clarify the effects of selective cutting on soil phosphorus availability in Korean pine broad-leaved forest, surface soil (0-10 cm) samples from original Korean pine broad-leaved forest and natural forests with mild, medium and intensive cutting disturbances were collected. The Sui modified Hedley phosphorus fractionation method was used to continuously extract soil samples and analyzed the differences and changes of soil phosphorus fractions from different experimental stands. The results showed that the soil total phosphorus content of Korean pine broad-leaved forest varied from 1.09 to 1.66 g·kg -1 , with the original stand and intensive cutting disturbance stand being the maximum and minimum one, respectively. The differences of soil total phosphorus content among cutting disturbance levels were significant. The Olsen phosphorus and phosphorus activation coefficients changed with an amplitude of 7.26-17.79 mg·kg -1 and 0.67%-1.07%, respectively. Both of them significantly decreased with the increase of selective cutting disturbance level. The concentrations of all P fractions except HCl-P o , i.e., H 2 O-P i , NaHCO 3 -P, NaOH-P, HCl-P i , Residual-P, decreased with increasing cutting disturbance levels compared with original forest. The correlation coefficient between H 2 O-P i and soil Olsen phosphorus was the highest (0.98), though it only accounted for 1.5%-2.2% of the total phosphorus. NaOH-P content contributed to more than 48.0% of the total phosphorus, acknowledged as the potential source of soil phosphorus. In conclusion, selective cutting disturbance could constrain phosphorus storage and soil phosphorus availabi-lity of the Korean pine broad-leaved forests by significantly reducing the content of soil inorganic phosphorus and NaOH-P o , and such trends were positively dependent on the intensity of selective cutting.

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

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    Azita Ahmad Zawawi

    2015-04-01

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

  2. 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.

  3. Combined community ecology and floristics, a synthetic study on the upper montane evergreen broad-leaved forests in Yunnan, southwestern China

    Institute of Scientific and Technical Information of China (English)

    Hua Zhu; Yong Chai; Shisun Zhou; Lichun Yan; Jipu Shi; Guoping Yang

    2016-01-01

    The upper montane evergreen broad-leaved forest in Yunnan occurs mainly in the zone of persistent cloud and has a discontinuous, island-like, distribution. It is diverse, rich in endemic species, and likely to be sensitive to climate change. Six 1-ha sampling plots were established across the main distribution area of the upper montane evergreen broad-leaved forest in Yunnan. All trees with d.b.h.>1 cm in each plot were identified. Patterns of seed plant distributions were quantified at the specific, generic and family levels. The forests are dominated by the families Fagaceae, Lauraceae, Theaceae and Magnoliaceae, but are very diverse with only a few species shared between sites. Floristic similarities at the family and generic level were high, but they were low at the specific level, with species complementarity between plots. Diversity varied greatly among sites, with greater species richness and more rare species in western Yunnan than central Yunnan. The flora is dominated by tropical biogeographical elements, mainly the pantropic and the tropical Asian distributions at the family and genus levels. In contrast, at the species level, the flora is dominated by the southwest or the southeast China distributions, including Yunnan endemics. This suggests that the flora of the upper montane forest in Yunnan could have a tropical floristic origin, and has adapted to cooler temperatures with the uplift of the Himalayas. Due to great sensitivity to climate, high endemism and species complementarity, as well as the discontinuous, island-like, distribution patterns of the upper montane forest in Yunnan, the regional conservation of the forest is especially needed.

  4. Interpretation of Upper-Storey Canopy Area in Subtropical Broad-leaved Forests in Okinawa Island Using Laser Scanning Data

    International Nuclear Information System (INIS)

    Noor Janatun Naim Jemali; Shiba, M.; Azita Ahmad Zawawi; Noor Janatun Naim Jemali

    2015-01-01

    Conventional forest inventory practice took huge of effort, and is time- and cost- consuming. With the aid of remote sensing technology by light detection and ranging (LiDAR), those unbearable factors could be minimized. LiDAR is able to capture forest characteristic information and is well known for estimating forest structure accurately in many studies. Forest monitoring related to forest resource inventory (FRI) becomes more effective by utilizing LiDAR data and it is tremendously useful, especially to distinguish information on density, growth and distribution of trees in a selected area. In this study, LiDAR data was utilized aimed to delineate crown cover and estimate upper-storey canopy area in Yambaru Forest using object-based segmentation and classification techniques. Agreement between field survey and LiDAR data analysis showed that only 33.7 % of upper-storey canopy area was successfully delineated. The low accuracy level of canopy detection in Yambaru Forest area was expected mainly due to tree structure, density and topographic condition. (author)

  5. [Effects of simulated nitrogen deposition on soil microbial biomass carbon and nitrogen in natural evergreen broad-leaved forest in the Rainy Area of West China].

    Science.gov (United States)

    Zhou, Shi Xing; Zou, Cheng; Xiao, Yong Xiang; Xiang, Yuan Bin; Han, Bo Han; Tang, Jian Dong; Luo, Chao; Huang, Cong de

    2017-01-01

    To understand the effects of increasing nitrogen deposition on soil microbial biomass carbon (MBC) and nitrogen(MBN), an in situ experiment was conducted in a natural evergreen broad-leaved forest in Ya'an City, Sichuan Province. Four levels of nitrogen deposition were set: i.e., control (CK, 0 g N·m -2 ·a -1 ), low nitrogen (L, 5 g N·m -2 ·a -1 ), medium nitrogen (M, 15 g N·m -2 ·a -1 ), and high nitrogen (H, 30 g N·m -2 ·a -1 ). The results indicated that nitrogen deposition significantly decreased MBC and MBN in the 0-10 cm soil layer, and as N de-position increased, the inhibition effect was enhanced. L and M treatments had no significant effect on MBC and MBN in the 10-20 cm soil layer, while H treatment significantly reduced. The influence of N deposition on MBC and MBN was weakened with the increase of soil depth. MBC and MBN had obvious seasonal dynamic, which were highest in autumn and lowest in summer both in the 0-10 and 10-20 cm soil layers. The fluctuation ranges of soil microbial biomass C/N were respectively 10.58-11.19 and 9.62-12.20 in the 0-10 cm and 10-20 cm soil layers, which indicated that the fungi hold advantage in the soil microbial community in this natural evergreen broad-leaved forest.

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

    Directory of Open Access Journals (Sweden)

    Tang, C. Q.

    2015-12-01

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

  7. Modeling biophysical properties of broad-leaved stands in the hyrcanian forests of Iran using fused airborne laser scanner data and ultraCam-D images

    Science.gov (United States)

    Mohammadi, Jahangir; Shataee, Shaban; Namiranian, Manochehr; Næsset, Erik

    2017-09-01

    Inventories of mixed broad-leaved forests of Iran mainly rely on terrestrial measurements. Due to rapid changes and disturbances and great complexity of the silvicultural systems of these multilayer forests, frequent repetition of conventional ground-based plot surveys is often cost prohibitive. Airborne laser scanning (ALS) and multispectral data offer an alternative or supplement to conventional inventories in the Hyrcanian forests of Iran. In this study, the capability of a combination of ALS and UltraCam-D data to model stand volume, tree density, and basal area using random forest (RF) algorithm was evaluated. Systematic sampling was applied to collect field plot data on a 150 m × 200 m sampling grid within a 1100 ha study area located at 36°38‧- 36°42‧N and 54°24‧-54°25‧E. A total of 308 circular plots (0.1 ha) were measured for calculation of stand volume, tree density, and basal area per hectare. For each plot, a set of variables was extracted from both ALS and multispectral data. The RF algorithm was used for modeling of the biophysical properties using ALS and UltraCam-D data separately and combined. The results showed that combining the ALS data and UltraCam-D images provided a slight increase in prediction accuracy compared to separate modeling. The RMSE as percentage of the mean, the mean difference between observed and predicted values, and standard deviation of the differences using a combination of ALS data and UltraCam-D images in an independent validation at 0.1-ha plot level were 31.7%, 1.1%, and 84 m3 ha-1 for stand volume; 27.2%, 0.86%, and 6.5 m2 ha-1 for basal area, and 35.8%, -4.6%, and 77.9 n ha-1 for tree density, respectively. Based on the results, we conclude that fusion of ALS and UltraCam-D data may be useful for modeling of stand volume, basal area, and tree density and thus gain insights into structural characteristics in the complex Hyrcanian forests.

  8. Growing season variability of net ecosystem CO2 exchange and evapotranspiration of a sphagnum mire in the broad-leaved forest zone of European Russia

    International Nuclear Information System (INIS)

    Olchev, A; Volkova, E; Karataeva, T; Novenko, E

    2013-01-01

    The spatial and temporal variability of net ecosystem exchange (NEE) of CO 2 and evapotranspiration (ET) of a karst-hole sphagnum peat mire situated at the boundary between broad-leaved and forest–steppe zones in the central part of European Russia in the Tula region was described using results from field measurements. NEE and ET were measured using a portable measuring system consisting of a transparent ventilated chamber combined with an infrared CO 2 /H 2 O analyzer, LI-840A (Li-Cor, USA) along a transect from the southern peripheral part of the mire to its center under sunny clear-sky weather conditions in the period from May to September of 2012 and in May 2013. The results of the field measurements showed significant spatial and temporal variability of NEE and ET that was mainly influenced by incoming solar radiation and ground water level. The seasonal patterns of NEE and ET within the mire were quite different. During the entire growing season the central part of the mire was a sink of CO 2 for the atmosphere. NEE reached maximal values in June–July (−6.8 ± 4.2 μmol m −2 s −1 ). The southern peripheral part of the mire, due to strong shading by the surrounding forest, was a sink of CO 2 for the atmosphere in June–July only. ET reached maximal values in the well-lighted central parts of the mire in May (0.34 ± 0.20 mm h −1 ) mainly because of high air and surface temperatures and the very wet upper peat horizon and sphagnum moss. Herbaceous species made the maximum contribution to the total gross primary production (GPP) in both the central and the peripheral parts of the mire. The contribution of sphagnum to the total GPP of these plant communities was relatively small and ranged on sunny days of July–August from −1.1 ± 1.1 mgC g −1 of dry weight (DW) per hour in the peripheral zone of the mire to −0.6 ± 0.2 mgC g −1 DW h −1 at the mire center. The sphagnum layer made the maximum contribution to total ET at the mire center (0

  9. Responses of fine roots and soil N availability to short-term nitrogen fertilization in a broad-leaved Korean pine mixed forest in northeastern China.

    Directory of Open Access Journals (Sweden)

    Cunguo Wang

    Full Text Available Knowledge of the responses of soil nitrogen (N availability, fine root mass, production and turnover rates to atmospheric N deposition is crucial for understanding fine root dynamics and functioning in forest ecosystems. Fine root biomass and necromass, production and turnover rates, and soil nitrate-N and ammonium-N in relation to N fertilization (50 kg N ha(-1 year(-1 were investigated in a temperate forest over the growing season of 2010, using sequential soil cores and ingrowth cores methods. N fertilization increased soil nitrate-N by 16% (P<0.001 and ammonium-N by 6% (P<0.01 compared to control plots. Fine root biomass and necromass in 0-20 cm soil were 13% (4.61 vs. 5.23 Mg ha(-1, P<0.001 and 34% (1.39 vs. 1.86 Mg ha(-1, P<0.001 less in N fertilization plots than those in control plots. The fine root mass was significantly negatively correlated with soil N availability and nitrate-N contents, especially in 0-10 cm soil layer. Both fine root production and turnover rates increased with N fertilization, indicating a rapid underground carbon cycling in environment with high nitrogen levels. Although high N supply has been widely recognized to promote aboveground growth rates, the present study suggests that high levels of nitrogen supply may reduce the pool size of the underground carbon. Hence, we conclude that high levels of atmospheric N deposition will stimulate the belowground carbon cycling, leading to changes in the carbon balance between aboveground and underground storage. The implications of the present study suggest that carbon model and prediction need to take the effects of nitrogen deposition on underground system into account.

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

    Science.gov (United States)

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

    2015-05-01

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

  11. 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...

  12. Functional role of the herbaceous layer in eastern deciduous forest

    Science.gov (United States)

    Katherine J. Elliott; James M. Vose; Jennifer D. Knoepp; Barton D. Clinton; Brian D. Kloeppel

    2014-01-01

    The importance of the herbaceous layer in regulating ecosystem processes in deciduous forests is generally unknown. We use a manipulative study in a rich, mesophytic cove forest in the southern Appalachians to test the following hypotheses: (i) the herbaceous functional group (HFG) in mesophytic coves accelerates carbon and nutrient cycling, (ii) high litter quality...

  13. The Influence of Forest Management Regimes on Deforestation in a Central Indian Dry Deciduous Forest Landscape

    OpenAIRE

    Shivani Agarwal; Harini Nagendra; Rucha Ghate

    2016-01-01

    This research examines the impact of forest management regimes, with various degrees of restriction, on forest conservation in a dry deciduous Indian forest landscape. Forest change is mapped using Landsat satellite images from 1977, 1990, 1999, and 2011. The landscape studied has lost 1478 km2 of dense forest cover between 1977 and 2011, with a maximum loss of 1002 km2 of dense forest between 1977 and 1990. The number of protected forest areas has increased, concomitant with an increase in r...

  14. Annual cycle of solar radiation in a deciduous forest

    International Nuclear Information System (INIS)

    Hutchison, B.A.; Matt, D.R.

    1977-01-01

    Periodic solar radiation measurements within and above an east Tennessee Liriodendron forest and continuous records of insolation from a nearby NOAA weather station were used to derive an approximation of the animal radiation regime within and above the deciduous forest. The interaction of changing solar elevations, insolation, and forest phenology are shown to control the radiation climate within the forest. Maximum radiation penetrates the forest in early spring as solar paths rise higher in the sky each day just prior to leaf expansion. After leaf expansion begins, average radiation received within the forest decreases rapidly despite continued increases in solar elevations and daily insolation. This forest attains full leaf in early June and from then until the advent of leaf abscission near the autumnal equinox, forest structure remains relatively static. Solar elevations and daily insolation decline following the summer solstice, however, and as a result, average radiation penetrating the forest slowly declines throughout the summer reaching an annual minimum in early autumn. With leaf fall, slightly increased amounts of radiation penetrate the forest but as within-forest solar paths continue to lengthen, radiation within the forest again declines. Minimum amounts of solar radiation penetrate the leafless forest around the winter solstice

  15. 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,

  16. Organic carbon efflux from a deciduous forest catchment in Korea

    Directory of Open Access Journals (Sweden)

    S. J. Kim

    2010-04-01

    Full Text Available Soil infiltration and surface discharge of precipitation are critical processes that affect the efflux of Dissolved Organic Carbon (DOC and Particulate Organic Carbon (POC in forested catchments. Concentrations of DOC and POC can be very high in the soil surface in most forest ecosystems and their efflux may not be negligible particularly under the monsoon climate. In East Asia, however, there are little data available to evaluate the role of such processes in forest carbon budget. In this paper, we address two basic questions: (1 how does stream discharge respond to storm events in a forest catchment? and (2 how much DOC and POC are exported from the catchment particularly during the summer monsoon period? To answer these questions, we collected hydrological data (e.g., precipitation, soil moisture, runoff discharge, groundwater level and conducted hydrochemical analyses (including DOC, POC, and six tracers in a deciduous forest catchment in Gwangneung National Arboretum in west-central Korea. Based on the end-member mixing analysis of the six storm events during the summer monsoon in 2005, the surface discharge was estimated as 30 to 80% of the total runoff discharge. The stream discharge responded to precipitation within 12 h during these storm events. The annual efflux of DOC and POC from the catchment was estimated as 0.04 and 0.05 t C ha−1 yr−1, respectively. Approximately 70% of the annual organic carbon efflux occurred during the summer monsoon period. Overall, the annual efflux of organic carbon was estimated to be about 10% of the Net Ecosystem carbon Exchange (NEE obtained by eddy covariance measurement at the same site. Considering the current trends of increasing intensity and amount of summer rainfall and the large interannual variability in NEE, ignoring the organic carbon efflux from forest catchments would result in an inaccurate estimation of the carbon sink strength of forest ecosystems in the monsoon

  17. Forest meteorology research within the Oak Ridge site, eastern deciduous forest biome, USIBP

    International Nuclear Information System (INIS)

    Hutchison, B.A.; Matt, D.R.

    1977-01-01

    The data presented here indicate that the diurnal trends in forest microclimate are dominated by the diurnal trend in incident solar radiation amounts and the diurnal changes in solar elevations. Absolute values of these microclimatic variables, on the other hand, reflect strongly, the synoptic climatic conditions present and, to a lesser degree, the interactions among synoptic climatic parameters, forest structure, forest physiology, and soil moisture conditions. The seasonal changes in forest microclimate are the result of changes in incident radiation amounts, earth-sun geometry, and phenological change in forest structure along with seasonal changes in synoptic climatic parameters. The temporal and spatial variations of solar radiation within and above a deciduous forest composed predominately of tulip poplar (biriodendron tulipifera) were documented and on attempt was made to relate the variations to forest structure

  18. Invertebrate populations of the deciduous forest: fluctuations and relations to weather

    National Research Council Canada - National Science Library

    Kendeigh, S. Charles

    1979-01-01

    The major objectives of the present study are to analyze (a) the composition and relative population sizes of the larger invertebrate fauna of relatively undisturbed, near-virgin, stands of deciduous forest, (b...

  19. Arthropod vertical stratification in temperate deciduous forests: Implications for conservation oriented management

    Science.gov (United States)

    Ulyshen Michael

    2011-01-01

    Studies on the vertical distribution patterns of arthropods in temperate deciduous forests reveal highly stratified (i.e., unevenly vertically distributed) communities. These patterns are determined by multiple factors acting simultaneously, including: (1) time (forest age, season, time of day); (2) forest structure (height, vertical foliage complexity, plant surface...

  20. Spatial patterning of fuels and fire hazard across a central U.S. deciduous forest region

    Science.gov (United States)

    Michael C. Stambaugh; Daniel C. Dey; Richard P. Guyette; Hong S. He; Joseph M. Marschall

    2011-01-01

    Information describing spatial and temporal variability of forest fuel conditions is essential to assessing overall fire hazard and risk. Limited information exists describing spatial characteristics of fuels in the eastern deciduous forest region, particularly in dry oak-dominated regions that historically burned relatively frequently. From an extensive fuels survey...

  1. Phenology of selected herbaceous species of northern Wisconsin deciduous forests and forest roads

    International Nuclear Information System (INIS)

    Zavitkovski, J.

    1977-01-01

    Vegetative and reproductive phenophases were observed from 1970 to 1974 on 30 native and 8 introduced herbaceous species growing under deciduous forests and on an abandoned logging road in the Enterprise Radiation Forest in northern Wisconsin. Forest herbs started growing in the same order each year, but logging-road herbs varied. Growth initiation was more variable in the early-starting than in the late-starting species. In most years logging-road herbs started growth a few days earlier than forest herbs. Initiation of flowering of the 38 species was bimodal, culminating around mid-May for forest species and around mid-July for logging-road species. In general, the annual start of flowering varied less than the start of vegetative growth. Duration of flowering of most species was variable, however. Seed ripening times varied strikingly among species, ranging from 11 days for Taraxacum officinale to 101 days for Iris versicolor. Seeds of forest herbs took longer to ripen than those of logging-road species. On the basis of growth initiation of the 6 earliest species, spring arrival in 1970 to 1974 differed by 26 days and appeared to be related to snow disappearance. The growing season of most species paralleled cumulative current-year (May--July) and last-year (August--September) precipitation. Multiple regression analyses between precipitation and average length of growing season explained 87 percent of the total variation for forest herbs and 69 percent of that for logging-road herbs

  2. 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

  3. Calibration of the L-MEB model over a coniferous and a deciduous forest

    DEFF Research Database (Denmark)

    Grant, Jennifer P.; Saleh-Contell, Kauzar; Wigneron, Jean-Pierre

    2008-01-01

    In this paper, the L-band Microwave Emission of the Biosphere (L-MEB) model used in the Soil Moisture and Ocean Salinity (SMOS) Level 2 Soil Moisture algorithm is calibrated using L-band (1.4 GHz) microwave measurements over a coniferous (Pine) and a deciduous (mixed/Beech) forest. This resulted...

  4. Succesional change and resilience of a very dry tropical deciduous forest following shifting agriculture

    NARCIS (Netherlands)

    Lebrija Trejos, E.E.; Bongers, F.J.J.M.; Pérez-García, E.; Meave, J.

    2008-01-01

    We analyzed successional patterns in a very dry tropical deciduous forest by using 15 plots differing in age after abandonment and contrasted them to secondary successions elsewhere in the tropics. We used multivariate ordination and nonlinear models to examine changes in composition and structure

  5. Effects of seasonal variation of photosynthetic capacity on the carbon fluxes of a temperate deciduous forest

    Science.gov (United States)

    David Medvigy; Su-Jong Jeong; Kenneth L. Clark; Nicholas S. Skowronski; Karina V. R. Schäfer

    2013-01-01

    Seasonal variation in photosynthetic capacity is an important part of the overall seasonal variability of temperate deciduous forests. However, it has only recently been introduced in a few terrestrial biosphere models, and many models still do not include it. The biases that result from this omission are not well understood. In this study, we use the Ecosystem...

  6. 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

  7. The bacterial community inhabiting temperate deciduous forests is vertically stratified and undergoes seasonal dynamics

    Czech Academy of Sciences Publication Activity Database

    López-Mondéjar, Rubén; Voříšková, Jana; Větrovský, Tomáš; Baldrian, Petr

    2015-01-01

    Roč. 87, č. 1 (2015), s. 43-50 ISSN 0038-0717 R&D Projects: GA MŠk(CZ) EE2.3.30.0003; GA MŠk(CZ) ED1.1.00/02.0109; GA MŠk LD12048; GA MŠk LD12050 Institutional support: RVO:61388971 Keywords : Bacterial community * Deciduous forest * Forest soil Subject RIV: EE - Microbiology, Virology Impact factor: 4.152, year: 2015

  8. 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.

  9. HNO3 fluxes to a deciduous forest derived using gradient and REA methods

    DEFF Research Database (Denmark)

    Pryor, S.C.; Barthelmie, R.J.; Jensen, B.

    2002-01-01

    Summertime nitric acid concentrations over a deciduous forest in the midwestern United States are reported, which range between 0.36 and 3.3 mug m(-3). Fluxes to the forest are computed using the relaxed eddy accumulation technique and gradient methods. In accord with previous studies, the results...... indicate substantial uncertainties in the gradient-based calculations. The relaxed eddy accumulation (REA) derived fluxes are physically reasonable and are shown to be of similar magnitude to dry deposition estimates from gradient sampling. The REA derived mean deposition velocity is approximately 3 cm s......(-1), which is also comparable to growing season estimates derived by Meyers et al. for a similar deciduous forest. Occasional inverted concentration gradients and fluxes are observed but most are not statistically significant. Data are also presented that indicate substantial through canopy...

  10. The Pleistocene biogeography of eastern North America: A nonmigration scenario for deciduous forest

    Energy Technology Data Exchange (ETDEWEB)

    Loehle, C. [Argonne National Lab., IL (United States). Environmental Research Div.; Iltis, H. [Univ. of Wisconsin, Madison, WI (United States). Dept. of Botany

    1998-12-31

    The current reconstruction of the vegetation of eastern North America at the last glacial maximum postulates a very wide zone of tundra and boreal forest south of the ice. This reconstruction requires that the deciduous forest retreated far to the south. The authors believe that this reconstruction is seriously in error. Geologic evidence for glacial activity or tundra is absent from the southern Appalachians. Positive evidence for boreal forest is based on pollen identifications for Picea, Betula, and Pinus, when in reality southern members of these genera have pollen that cannot be distinguished from that of northern members. Further, pollen of typical southern species such as oaks and hickories occurs throughout profiles that past authors had labeled boreal. Pollen evidence for a far southern deciduous forest refuge is lacking. Data on endemics are particularly challenging for the scenario in which deciduous forest migrated to the south and back. The southern Appalachian region is rife with endemics that are often extreme-habitat specialists unable to migrate. The previously glaciated zone is almost completely lacking in endemics. Outlier populations, range boundaries, and absence of certain hybrids all argue against a large boreal zone. The new reconstruction postulates a cold zone no more than 75--100 miles wide south of the ice in the East.

  11. 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.

  12. 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...

  13. 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%.

  14. 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...

  15. 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.

  16. 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

  17. Soil macroinvertebrate communities across a productivity gradient in deciduous forests of eastern North America

    Science.gov (United States)

    Evelyn S. Wenk; Mac A. Callaham; Joseph O' Brien; Paul J. Hanson

    2016-01-01

    Within the temperate, deciduous forests of the eastern US, diverse soil-fauna communities are structured by a combination of environmental gradients and interactions with other biota. The introduction of non-native soil taxa has altered communities and soil processes, and adds another degree of variability to these systems. We sampled soil macroinvertebrate abundance...

  18. Interannual Variations in Ecosystem Oxidative Ratio in Croplands, Deciduous Forest, Coniferous Forest, and Early Successional Forest Ecosystems

    Science.gov (United States)

    Masiello, C. A.; Hockaday, W. C.; Gallagher, M. E.; Calligan, L.

    2009-12-01

    Ecosystem net primary productivity (NPP) can vary significantly with annual variations in precipitation and temperature. These climate variations can also drive changes in plant carbon allocation patterns. Shifting allocation patterns can lead to variation in net ecosystem biochemical stocks (e.g. kg cellulose, lignin, protein, and lipid/ha), which can in turn lead to shifts in ecosystem oxidative ratio (OR). OR is the molar ratio of O2 released : CO2 fixed during biosynthesis. Major plant biochemicals vary substantially in oxidative ratio, ranging from average organic acid OR values of 0.75 to average lipid OR values of 1.37 (Masiello et al., 2008). OR is a basic property of ecosystem biochemistry, and is also an essential variable needed to constrain the size of the terrestrial biospheric carbon sink (Keeling et al., 1996). OR is commonly assumed to be 1.10 (e.g. Prentice et al., 2001), but small variations in net ecosystem OR can drive large errors in estimates of the size of the terrestrial carbon sink (Randerson et al., 2006). We hypothesized that interannual changes in climate may drive interannual variation in ecosystem OR values. Working at Kellogg Biological Station NSF LTER, we measured the annual average OR of coniferous and deciduous forests, an early successional forest, and croplands under both corn and soy. There are clear distinctions between individual ecosystems (e.g., the soy crops have a higher OR than the corn crops, and the coniferous forests have a higher OR than the deciduous forests), but the ecosystems themselves retained remarkably constant annual OR values between 1998 and 2008.

  19. Model of plutonium dynamics in a deciduous forest ecosystem

    International Nuclear Information System (INIS)

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

    1980-01-01

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

  20. Mathematical model of 137Cs dynamics in the deciduous forest

    International Nuclear Information System (INIS)

    Mamikhin, S.V.; Klyashtorin, A.L.

    1999-01-01

    A mathematical model of 137 Cs behaviour in the forest ecosystem is presented. The behaviour of this radionuclide is assumed to obey the same regularities as the behaviour of its stable chemical analogue, potassium. Radionuclide dynamics are considered in parallel with the dynamics of the phytomass. Radionuclides contained in the vegetation are pooled into two basic compartments: external and internal contamination, with separate analysis of each. The model was verified using the data obtained in the 30-km zone of the Chernobyl NPP in 1986-1994. The algorithm described was found to be the most efficient in terms of 137 Cs behaviour in the forest environments

  1. 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.

  2. Disturbance, complexity, and succession of net ecosystem production in North America’s temperate deciduous forests

    Energy Technology Data Exchange (ETDEWEB)

    Gough, Christopher; Curtis, Peter; Hardiman, Brady; Scheuermann, Cynthia; Bond-Lamberty, Benjamin

    2016-06-29

    Century-old forests in the U.S. upper Midwest and Northeast power much of North Amer- ica’s terrestrial carbon (C) sink, but these forests’ production and C sequestration capacity are expected to soon decline as fast-growing early successional species die and are replaced by slower growing late successional species. But will this really happen? Here we marshal empirical data and ecological theory to argue that substantial declines in net ecosystem production (NEP) owing to reduced forest growth, or net primary production (NPP), are not imminent in regrown temperate deciduous forests over the next several decades. Forest age and production data for temperate deciduous forests, synthesized from published literature, suggest slight declines in NEP and increasing or stable NPP during middle successional stages. We revisit long-held hypotheses by EP Odum and others that suggest low-severity, high-frequency disturbances occurring in the region’s aging forests will, against intuition, maintain NEP at higher-than- expected rates by increasing ecosystem complexity, sustaining or enhancing NPP to a level that largely o sets rising C losses as heterotrophic respiration increases. This theoretical model is also supported by biological evidence and observations from the Forest Accelerated Succession Experiment in Michigan, USA. Ecosystems that experience high-severity disturbances that simplify ecosystem complexity can exhibit substantial declines in production during middle stages of succession. However, observations from these ecosystems have exerted a disproportionate in uence on assumptions regarding the trajectory and magnitude of age-related declines in forest production. We conclude that there is a wide ecological space for forests to maintain NPP and, in doing so, lessens the declines in NEP, with signi cant implications for the future of the North American carbon sink. Our intellectual frameworks for understanding forest C cycle dynamics and resilience need to

  3. Factors for Microbial Carbon Sources in Organic and Mineral Soils from Eastern United States Deciduous Forests

    Energy Technology Data Exchange (ETDEWEB)

    Stitt, Caroline R. [Mills College, Oakland, CA (United States)

    2013-09-16

    Forest soils represent a large portion of global terrestrial carbon; however, which soil carbon sources are used by soil microbes and respired as carbon dioxide (CO2) is not well known. This study will focus on characterizing microbial carbon sources from organic and mineral soils from four eastern United States deciduous forests using a unique radiocarbon (14C) tracer. Results from the dark incubation of organic and mineral soils are heavily influenced by site characteristics when incubated at optimal microbial activity temperature. Sites with considerable differences in temperature, texture, and location differ in carbon source attribution, indicating that site characteristics play a role in soil respiration.

  4. 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.

  5. 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.

  6. 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)

  7. Simulation of water and carbon fluxes in a broad-leaved Korean pine forest in Changbai Mountains based on Biome-BGC model and Ensemble Kalman Filter method%基于Biome-BGC模型和集合卡尔曼滤波方法的阔叶红松林生态系统水碳通量模拟

    Institute of Scientific and Technical Information of China (English)

    郑磊; 宋世凯; 袁秀亮; 董嘉琪; 李龙辉

    2017-01-01

    数据同化为模型与遥感观测结合提供了一条有效的途径,通过在模型运行过程中融入遥感观测数据,调整模型运行轨迹从而降低模型误差,提高模拟精度.本文利用集合卡尔曼滤波(EnKF)算法同化生长季中分辨率成像光谱仪(MODIS)叶面积指数(LAI)与Biome-BGC模型模拟的LAI模拟长白山阔叶红松林的水碳通量.同时,通过改进模拟的雪面升华与土壤温度计算方法的参数,旨在降低冬季生态呼吸的模拟误差.结果表明,相对于原始模型,数据同化与模型改进后使得生态系统总初级生产力(GPP)的模拟值与观测值之间的相关系数提高0.06,中心化均方根误差(RMSE)降低0.48 g C·m-2·d-1;生态系统呼吸(RE)的相关系数提高0.02,中心化均方根误差降低0.20 g C·m-2·d-1;净生态系统碳交换量(NEE)相关系数提高0.35,中心化均方根误差降低0.50gC·m-2·d-1.同时,数据同化对蒸散发(ET)的模拟精度没有显著影响,改进的模型提高了其相关系数.基于EnKF算法的数据同化提高了长白山阔叶红松林碳通量模拟精度,对于精确估算区域碳通量有着重要的意义.%Data assimilation provides an effective way to integrate the model simulation and remote sensing observation,through the integration of remote sensing data in the run of the model,adjusting the model trajectory to reduce model error and improve simulation accuracy.This paper uses the ensemble Kalman filter (EnKF) assimilated MODIS LAI into the Biome-BGC model in growing season to simulate the water and carbon fluxes in a broad-leaved Korean pine forest in Changbai Mountains.At the same time,the simulated snow sublimation and the parameters of the calculation method of soil temperature are improved,which can effectively reduce the error of the ecological respiration in winter.The result shows that as compared with the original model simulated without data assimilation,the improved Biome-BGC model with the

  8. Influence of physiological phenology on the seasonal pattern of ecosystem respiration in deciduous forests.

    Science.gov (United States)

    Migliavacca, Mirco; Reichstein, Markus; Richardson, Andrew D; Mahecha, Miguel D; Cremonese, Edoardo; Delpierre, Nicolas; Galvagno, Marta; Law, Beverly E; Wohlfahrt, Georg; Black, T Andrew; Carvalhais, Nuno; Ceccherini, Guido; Chen, Jiquan; Gobron, Nadine; Koffi, Ernest; Munger, J William; Perez-Priego, Oscar; Robustelli, Monica; Tomelleri, Enrico; Cescatti, Alessandro

    2015-01-01

    Understanding the environmental and biotic drivers of respiration at the ecosystem level is a prerequisite to further improve scenarios of the global carbon cycle. In this study we investigated the relevance of physiological phenology, defined as seasonal changes in plant physiological properties, for explaining the temporal dynamics of ecosystem respiration (RECO) in deciduous forests. Previous studies showed that empirical RECO models can be substantially improved by considering the biotic dependency of RECO on the short-term productivity (e.g., daily gross primary production, GPP) in addition to the well-known environmental controls of temperature and water availability. Here, we use a model-data integration approach to investigate the added value of physiological phenology, represented by the first temporal derivative of GPP, or alternatively of the fraction of absorbed photosynthetically active radiation, for modeling RECO at 19 deciduous broadleaved forests in the FLUXNET La Thuile database. The new data-oriented semiempirical model leads to an 8% decrease in root mean square error (RMSE) and a 6% increase in the modeling efficiency (EF) of modeled RECO when compared to a version of the model that does not consider the physiological phenology. The reduction of the model-observation bias occurred mainly at the monthly time scale, and in spring and summer, while a smaller reduction was observed at the annual time scale. The proposed approach did not improve the model performance at several sites, and we identified as potential causes the plant canopy heterogeneity and the use of air temperature as a driver of ecosystem respiration instead of soil temperature. However, in the majority of sites the model-error remained unchanged regardless of the driving temperature. Overall, our results point toward the potential for improving current approaches for modeling RECO in deciduous forests by including the phenological cycle of the canopy. © 2014 John Wiley & Sons

  9. Invaders do not require high resource levels to maintain physiological advantages in a temperate deciduous forest.

    Science.gov (United States)

    Heberling, J Mason; Fridley, Jason D

    2016-04-01

    Non-native, invasive plants are commonly typified by trait strategies associated with high resource demands and plant invasions are often thought to be dependent upon site resource availability or disturbance. However, the invasion of shade-tolerant woody species into deciduous forests of the Eastern United States seems to contradict such generalization, as growth in this ecosystem is strongly constrained by light and, secondarily, nutrient stress. In a factorial manipulation of light and soil nitrogen availability, we established an experimental resource gradient in a secondary deciduous forest to test whether three common, woody, invasive species displayed increased metabolic performance and biomass production compared to six co-occurring woody native species, and whether these predicted differences depend upon resource supply. Using hierarchical Bayesian models of photosynthesis that included leaf trait effects, we found that invasive species exhibited functional strategies associated with higher rates of carbon gain. Further, invader metabolic and growth-related attributes were more responsive to increasing light availability than those of natives, but did not fall below average native responses even in low light. Surprisingly, neither group showed direct trait or growth responses to soil N additions. However, invasive species showed increased photosynthetic nitrogen use efficiencies with decreasing N availability, while that of natives remained constant. Although invader advantage over natives was amplified in higher resource conditions in this forest, our results indicate that some invasive species can maintain physiological advantages over co-occurring natives regardless of resource conditions.

  10. 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.

  11. Close relationship between spectral vegetation indices and Vcmax in deciduous and mixed forests

    Directory of Open Access Journals (Sweden)

    Yanlian Zhou

    2014-04-01

    Full Text Available Seasonal variations of photosynthetic capacity parameters, notably the maximum carboxylation rate, Vcmax, play an important role in accurate estimation of CO2 assimilation in gas-exchange models. Satellite-derived normalised difference vegetation index (NDVI, enhanced vegetation index (EVI and model-data fusion can provide means to predict seasonal variation in Vcmax. In this study, Vcmax was obtained from a process-based model inversion, based on an ensemble Kalman filter (EnKF, and gross primary productivity, and sensible and latent heat fluxes measured using eddy covariance technique at two deciduous broadleaf forest sites and a mixed forest site. Optimised Vcmax showed considerable seasonal and inter-annual variations in both mixed and deciduous forest ecosystems. There was noticeable seasonal hysteresis in Vcmax in relation to EVI and NDVI from 8 d composites of satellite data during the growing period. When the growing period was phenologically divided into two phases (increasing VIs and decreasing VIs phases, significant seasonal correlations were found between Vcmax and VIs, mostly showing R2>0.95. Vcmax varied exponentially with increasing VIs during the first phase (increasing VIs, but second and third-order polynomials provided the best fits of Vcmax to VIs in the second phase (decreasing VIs. The relationships between NDVI and EVI with Vcmax were different. Further efforts are needed to investigate Vcmax–VIs relationships at more ecosystem sites to the use of satellite-based VIs for estimating Vcmax.

  12. Retrieval of forest biomass for tropical deciduous mixed forest using ALOS PALSAR mosaic imagery and field plot data

    Science.gov (United States)

    Ningthoujam, Ramesh K.; Joshi, P. K.; Roy, P. S.

    2018-07-01

    Tropical forest is an important ecosystem rich in biodiversity and structural complexity with high woody biomass content. Longer wavelength radar data at L-band sensor provides improved forest biomass (AGB) information due to its higher penetration level and sensitivity to canopy structure. The study presents a regression based woody biomass estimation for tropical deciduous mixed forest dominated by Shorea robusta using ALOS PALSAR mosaic (HH, HV) and field data at the lower Himalayan belt of Northern India. For the purpose of understanding the scattering mechanisms at L-band from this forest type, Michigan Microwave Canopy Scattering model (MIMICS-I) was parameterized with field data to simulate backscatter across polarization and incidence range. Regression analysis between field measured forest biomass and L-band backscatter data from PALSAR mosaic show retrieval of woody biomass up to 100 Mg ha-1 with error between 92 and 94 Mg ha-1 and coefficient of determination (r2) between 0.53 and 0.55 for HH and HH + HV polarized channel at 0.25 ha resolution. This positive relationship could be due to strong volume scattering from ground/trunk interaction at HH-polarized while in combination with direct canopy scattering for HV-polarization at ALOS specific incidence angles as predicted by MIMICS-I model. This study has found that L-band SAR data from currently ALOS-1/-2 and upcoming joint NASA-ISRO SAR (NISAR) are suitable for mapping forest biomass ≤100 Mg ha-1 at 25 m resolution in far incidence range in dense deciduous mixed forest of Northern India.

  13. Trace gas exchange above the floor of a deciduous forest: 1. Evaporation and CO2 efflux

    Science.gov (United States)

    Baldocchi, Dennis D.; Meyers, Tilden P.

    1991-04-01

    The eddy correlation method has great potential for directly measuring trace gas fluxes at the floor of a forest canopy, but a thorough validation study has not been yet conducted. Another appeal of the eddy correlation method is its ability to study processes that regulate and modulate gas exchange between the soil/litter complex and the atmosphere that cannot be probed with chambers. In this paper we report on eddy correlation measurements of water vapor, sensible heat, and carbon dioxide exchange that were made at the floor of a deciduous forest. The validity of the eddy correlation method to measure the emission of water vapor and CO2 from a deciduous forest floor is demonstrated by our ability to close the surface energy budget during periods that meet the requirements of the technique. Water vapor fluxes from a dry forest floor are strongly influenced by large-scale turbulent events that penetrate deep into the canopy. The frequency of these turbulent events prevents equilibrium evaporation rates from being achieved because the dynamic time constant for water vapor exchange is longer. Consequently, maximal evaporation rates are capped to rates defined by the product of the driving potential of the atmosphere and the surface conductance. On the other hand, evaporation from a wet forest floor proceeds at rates reaching or exceeding equilibrium evaporation and are highly correlated with static pressure fluctuations. CO2 efflux rates are governed by litter and soil temperature, as expected. But we also find a significant correlation between static pressure fluctuations and soil/litter CO2 exchange rates.

  14. How Biotic Differentiation of Human Impacted Nutrient Poor Deciduous Forests Can Affect the Preservation Status of Mountain Forest Vegetation

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    Tomasz Durak

    2016-10-01

    Full Text Available A significant loss of biodiversity resulting from human activity has caused biotic homogenisation to become the dominant process shaping forest communities. In this paper, we present a rare case of biotic differentiation in European temperate deciduous forest herb layer vegetation. The process is occurring in nutrient poor oak-hornbeam forests in mountain areas (Polish Eastern Carpathians, Central Europe where non-timber use was converted into conventional forest management practice. This change contributed to increases in the nitrogen content and pH reaction of the soil that, contrary to predominant beliefs on the negative impact of habitat eutrophication on diversity, did not result in a decrease in the latter. We discuss possible reasons for this phenomenon that indicate the important role of tree stand composition (an increasing admixture of beech worsening the trophic properties of the soil. The second issue considered involves the effect of the changes in herb species composition of oak-hornbeam forest on its distinctiveness from the beech forest predominating in the Polish Eastern Carpathians. Unfortunately, despite the increase in the species compositional dissimilarity of oak-hornbeam forest, a reduction in their distinctiveness in relation to the herb species composition of beech forest was found. Such a phenomenon is an effect of the major fragmentation of oak-hornbeam forests, a spread of beech forest-type species, and forest management that gives preference to beech trees. Consequently, it can be expected that changes occurring in oak-hornbeam forest vegetation will contribute to a decrease in the forest vegetation variability at the regional scale.

  15. Impacts of experimentally applied mountain biking and hiking on vegetation and soil of a deciduous forest.

    Science.gov (United States)

    Thurston, E; Reader, R J

    2001-03-01

    Many recent trail degradation problems have been attributed to mountain biking because of its alleged capacity to do more damage than other activities, particularly hiking. This study compared the effects of experimentally applied mountain biking and hiking on the understory vegetation and soil of a deciduous forest. Five different intensities of biking and hiking (i.e., 0, 25, 75, 200 and 500 passes) were applied to 4-m-long x 1-m-wide lanes in Boyne Valley Provincial Park, Ontario, Canada. Measurements of plant stem density, species richness, and soil exposure were made before treatment, two weeks after treatment, and again one year after treatment. Biking and hiking generally had similar effects on vegetation and soil. Two weeks after treatment, stem density and species richness were reduced by up to 100% of pretreatment values. In addition, the amount of soil exposed increased by up to 54%. One year later, these treatment effects were no longer detectable. These results indicate that at a similar intensity of activity, the short-term impacts of mountain biking and hiking may not differ greatly in the undisturbed area of a deciduous forest habitat. The immediate impacts of both activities can be severe but rapid recovery should be expected when the activities are not allowed to continue. Implications of these results for trail recreation are discussed.

  16. 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

  17. Linear 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.

    1977-01-01

    Systems ecology techniques have been useful in simulating the fate and dynamics of radionuclides in forest ecosystems. The applications of systems models in this context are twofold: projection of the time-dependent distribution of radioisotopes among various ecosystems components, and manipulation of the modeled system to determine the sensitivity of components to variation in transfer coefficients and, thereby, identify critical fluxes affecting system behavior. The present paper describes a systems model that projects the possible fate of plutonium in a deciduous forest ecosystem. The isotopes of interest are 239 Pu and 240 Pu which have physical half lives of 2.44 x 10 4 and 6540 years, respectively. These isotopes are indistinguishable by alpha spectrometry hence 239 Pu is used to refer to both

  18. 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.

  19. 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

  20. 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

  1. 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.

  2. Ecological effects of pipeline construction through deciduous forested wetlands, Midland County, Michigan

    International Nuclear Information System (INIS)

    Zellmer, S.D.; Rastorfer, J.R.; Van Dyke, G.D.

    1991-07-01

    Implementation of recent federal and state regulations promulgated to protect wetlands makes information on effects of gas pipeline rights-of-way (ROWs) in wetlands essential to the gas pipeline industry. This study is designed to record vegetational changes induced by the construction of a large-diameter gas pipeline through deciduous forested wetlands. Two second-growth forested wetland sites mapped as Lenawee soils, one mature and one subjected to recent selective logging, were selected in Midland County, Michigan. Changes in the adjacent forest and successional development on the ROW are being documented. Cover-class estimates are being made for understory and ROW plant species using 1 x1-m quadrats. Counts are also being made for all woody species with stems < 2 cm in diameter at breast height (dbh) in the same plots used for cover-class estimates. Individual stem diameters and species counts are being recorded for all woody understory and overstory plants with stems ≥2 cm dbh in 10 x 10-m plots. Although analyses of the data have not been completed, preliminary analyses indicate that some destruction of vegetation at the ROW forest edge may have been avoidable during pipeline construction. Rapid regrowth of many native wetland plant species on the ROW occurred because remnants of native vegetation and soil-bearing propagules of existing species survived on the ROW after pipeline construction and seeding operations. 91 refs., 11 figs., 3 tabs

  3. Ecological effects of pipeline construction through deciduous forested wetlands, Midland County, Michigan

    Energy Technology Data Exchange (ETDEWEB)

    Zellmer, S.D. (Argonne National Lab., IL (United States)); Rastorfer, J.R. (Chicago State Univ., IL (United States). Dept. of Biological Sciences ANL/CSU Cooperative Herbarium, Chicago, IL (United States)); Van Dyke, G.D. (Trinity Christian Coll., Palos Heights, IL (United States). Dept. of Biology)

    1991-07-01

    Implementation of recent federal and state regulations promulgated to protect wetlands makes information on effects of gas pipeline rights-of-way (ROWs) in wetlands essential to the gas pipeline industry. This study is designed to record vegetational changes induced by the construction of a large-diameter gas pipeline through deciduous forested wetlands. Two second-growth forested wetland sites mapped as Lenawee soils, one mature and one subjected to recent selective logging, were selected in Midland County, Michigan. Changes in the adjacent forest and successional development on the ROW are being documented. Cover-class estimates are being made for understory and ROW plant species using 1 {times}1-m quadrats. Counts are also being made for all woody species with stems < 2 cm in diameter at breast height (dbh) in the same plots used for cover-class estimates. Individual stem diameters and species counts are being recorded for all woody understory and overstory plants with stems {ge}2 cm dbh in 10 {times} 10-m plots. Although analyses of the data have not been completed, preliminary analyses indicate that some destruction of vegetation at the ROW forest edge may have been avoidable during pipeline construction. Rapid regrowth of many native wetland plant species on the ROW occurred because remnants of native vegetation and soil-bearing propagules of existing species survived on the ROW after pipeline construction and seeding operations. 91 refs., 11 figs., 3 tabs.

  4. Processes governing yearly variations in carbon sequestration at a temperate deciduous forest

    Science.gov (United States)

    Barr, J. G.; Fuentes, J. D.; Staebler, R.; Lee, X.

    2001-12-01

    Since 1995, processes governing the net ecosystem exchange (NEE) of carbon dioxide have been continuously investigated at the CFB Borden temperate mixed deciduous forest in Ontario, Canada. On a yearly basis, the rates of NEE for this forest range from 0.3 to 2.5 t C ha-1. For the 1996 to 1999 period, the forest sequestered the most carbon and had the greatest seasonal carbon dioxide flux in 1997. This seasonal flux is defined as the average daily rate of NEE over the course of the growing period and is the single most important factor governing yearly NEE. Such factors as soil temperature, timing of soil thawing, and respiratory processes exert only minor influences on the yearly variability in NEE. In this presentation, we will provide evidence to support the hypothesis that maximum Rubisco capacity per unit foliage element is one key control on the NEE variability. Additionally, changes in diffuse photosysnthetically active irradiance contribute to the variability observed in NEE. We will present results from both data analyses and outputs from a biospheric modeling system which was employed to investigate seasonal rates of NEE for the Borden forest.

  5. Species-specific effects of Asian and European earthworms on microbial communities in Mid-Atlantic deciduous forests

    Science.gov (United States)

    Earthworm species with different feeding, burrowing, and/or casting behaviors can lead to distinct microbial communities through complex direct and indirect processes. European earthworm invasion into temperate deciduous forests in North America has been shown to alter microbial biomass in the soil ...

  6. Spatiotemporal phenological changes in fall foliage peak coloration in deciduous forest and the responses to climatic variation

    Science.gov (United States)

    Xie, Y.; Wilson, A. M.

    2017-12-01

    Plant phenology studies typically focus on the beginning and end of the growing season in temperate forests. We know too little about fall foliage peak coloration, which is a bioindicator of plant response in autumn to environmental changes, an important visual cue in fall associated with animal activities, and a key element in fall foliage ecotourism. Spatiotemporal changes in timing of fall foliage peak coloration of temperate forests and the associated environmental controls are not well understood. In this study, we examined multiple color indices to estimate Land Surface Phenology (LSP) of fall foliage peak coloration of deciduous forest in the northeastern USA using Moderate Resolution Imaging Spectroradiometer (MODIS) daily imagery from 2000 to 2015. We used long term phenology ground observations to validate our estimated LSP, and found that Visible Atmospherically Resistant Index (VARI) and Plant Senescence Reflectance Index (PSRI) were good metrics to estimate peak and end of leaf coloration period of deciduous forest. During the past 16 years, the length of period with peak fall foliage color of deciduous forest at southern New England and northern Appalachian forests regions became longer (0.3 7.7 days), mainly driven by earlier peak coloration. Northern New England, southern Appalachian forests and Ozark and Ouachita mountains areas had shorter period (‒0.2 ‒9.2 days) mainly due to earlier end of leaf coloration. Changes in peak and end of leaf coloration not only were associated with changing temperature in spring and fall, but also to drought and heat in summer, and heavy precipitation in both summer and fall. The associations between leaf peak coloration phenology and climatic variations were not consistent among ecoregions. Our findings suggested divergent change patterns in fall foliage peak coloration phenology in deciduous forests, and improved our understanding in the environmental control on timing of fall foliage color change.

  7. 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.

  8. Effects of gamma radiation on vegetative and reproductive phenology of herbaceous species of northern deciduous forests

    International Nuclear Information System (INIS)

    Zavitkovski, J.

    1977-01-01

    Vegetative and reproductive phenology of 38 herbaceous species of northern deciduous forests and forest roads were observed for 5 years, before (1970 and 1971), during (1972), and after (1973 and 1974) gamma irradiation. During the preirradiation years the occurrence of key vegetative and reproductive phenophases was very uniform throughout the area. This uniformity was upset by irradiation. In 1972 signs of senescence appeared earlier in most plants of the high-radiation zone (greater than or equal to 300 r/day) than in those outside that zone. In 1973 initiation of growth and completion of leaf growth of most plants was delayed by several weeks in the high-radiation zone. In both years the length of growing season was significantly shortened; this was also reflected in reduced biomass production. Vegetative development of surviving plants normalized in 1974. In 1972 flowering of forest herbs (which as a group flower early in the spring) was not affected by radiation, but that of summer-flowering logging-road herbs was delayed because the critical radiation doses were reached at that time. In 1973 all five flowering phenophases of the logging-road herbs were delayed about 3 weeks in the high-radiation zone. Normalization of reproductive phenophases became evident in 1974

  9. 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.

  10. The species richness-productivity relationship in the herb layer of European deciduous forests

    Czech Academy of Sciences Publication Activity Database

    Axmanová, I.; Chytrý, M.; Zelený, D.; Ching-Feng, L.; Vymazalová, M.; Danihelka, Jiří; Horsák, M.; Kočí, M.; Kubešová, S.; Lososová, Z.; Otýpková, Z.; Tichý, L.; Martynenko, V. B.; Baisheva, E. Z.; Schuster, B.; Diekmann, M.

    2012-01-01

    Roč. 21, č. 6 (2012), s. 657-667 ISSN 1466-822X Institutional support: RVO:67985939 Keywords : broad-leaved woodland * diversity - productivity relationship * herb-layer biomass Subject RIV: EF - Botanics Impact factor: 7.223, year: 2012

  11. 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.

  12. 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.

  13. 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.

  14. 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.

  15. 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

  16. 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...

  17. 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

  18. Effects of Habitat Structure and Fragmentation on Diversity and Abundance of Primates in Tropical Deciduous Forests in Bolivia.

    Science.gov (United States)

    Pyritz, Lennart W; Büntge, Anna B S; Herzog, Sebastian K; Kessler, Michael

    2010-10-01

    Habitat structure and anthropogenic disturbance are known to affect primate diversity and abundance. However, researchers have focused on lowland rain forests, whereas endangered deciduous forests have been neglected. We aimed to investigate the relationships between primate diversity and abundance and habitat parameters in 10 deciduous forest fragments southeast of Santa Cruz, Bolivia. We obtained primate data via line-transect surveys and visual and acoustic observations. In addition, we assessed the vegetation structure (canopy height, understory density), size, isolation time, and surrounding forest area of the fragments. We interpreted our results in the context of the historical distribution data for primates in the area before fragmentation and interviews with local people. We detected 5 of the 8 historically observed primate species: Alouatta caraya, Aotus azarae boliviensis, Callithrix melanura, Callicebus donacophilus, and Cebus libidinosus juruanus. Total species number and detection rates decreased with understory density. Detection rates also negatively correlated with forest areas in the surroundings of a fragment, which may be due to variables not assessed, i.e., fragment shape, distance to nearest town. Observations for Alouatta and Aotus were too few to conduct further statistics. Cebus and Callicebus were present in 90% and 70% of the sites, respectively, and their density did not correlate with any of the habitat variables assessed, signaling high ecological plasticity and adaptability to anthropogenic impact in these species. Detections of Callithrix were higher in areas with low forest strata. Our study provides baseline data for future fragmentation studies in Neotropical dry deciduous forests and sets a base for specific conservation measures.

  19. Broadleaf deciduous forest counterbalanced the direct effect of climate on Holocene fire regime in hemiboreal/boreal region (NE Europe)

    Science.gov (United States)

    Feurdean, Angelica; Veski, Siim; Florescu, Gabriela; Vannière, Boris; Pfeiffer, Mirjam; O'Hara, Robert B.; Stivrins, Normunds; Amon, Leeli; Heinsalu, Atko; Vassiljev, Jüri; Hickler, Thomas

    2017-08-01

    Disturbances by fire are essential for the functioning of boreal/hemiboreal forests, but knowledge of long-term fire regime dynamics is limited. We analysed macrocharcoal morphologies and pollen of a sediment record from Lake Lielais Svētiņu (eastern Latvia), and in conjunction with fire traits analysis present the first record of Holocene variability in fire regime, fuel sources and fire types in boreal forests of the Baltic region. We found a phase of moderate to high fire activity during the cool and moist early (mean fire return interval; mFRI of ∼280 years; 11,700-7500 cal yr BP) and the late (mFRI of ∼190 years; 4500-0 cal yr BP) Holocene and low fire activity (mFRI of ∼630 years) during the Holocene Thermal Optimum (7500-4500 cal yr BP). Charcoal morphotypes and the pollen record show the predominance of frequent surface fires, occasionally transitioning to the crown during Pinus sylvestris-Betula boreal forests and less frequent surface fires during the dominance of temperate deciduous forests. In contrast to the prevailing opinion that fires in boreal forests are mostly low to moderate severity surface fires, we found evidence for common occurrence of stand-replacing crown fires in Picea abies canopy. Our results highlight that charcoal morphotypes analysis allows for distinguishing the fuel types and surface from crown fires, therefore significantly advancing our interpretation of fire regime. Future warmer temperatures and increase in the frequency of dry spells and abundant biomass accumulation can enhance the fire risk on the one hand, but will probably promote the expansion of broadleaf deciduous forests to higher latitudes, on the other hand. By highlighting the capability of broadleaf deciduous forests to act as fire-suppressing landscape elements, our results suggest that fire activity may not increase in the Baltic area under future climate change.

  20. 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

  1. 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.

  2. 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.

  3. Edge Effects on Community and Social Structure of Northern Temperate Deciduous Forest Ants

    Directory of Open Access Journals (Sweden)

    Valerie S. Banschbach

    2012-01-01

    Full Text Available Determining how ant communities are impacted by challenges from habitat fragmentation, such as edge effects, will help us understand how ants may be used as a bioindicator taxon. To assess the impacts of edge effects upon the ant community in a northern temperate deciduous forest, we studied edge and interior sites in Jericho, VT, USA. The edges we focused upon were created by recreational trails. We censused the ants at these sites for two consecutive growing seasons using pitfall traps and litter plot excavations. We also collected nests of the most common ant species at our study sites, Aphaenogaster rudis, for study of colony demography. Significantly greater total numbers of ants and ant nests were found in the edge sites compared to the interior sites but rarefaction analysis showed no significant difference in species richness. Aphaenogaster rudis was the numerically dominant ant in the habitats sampled but had a greater relative abundance in the interior sites than in the edge sites both in pitfall and litter plot data. Queen number of A. rudis significantly differed between the nests collected in the edge versus the interior sites. Habitat-dependent changes in social structure of ants represent another possible indicator of ecosystem health.

  4. Missing ozone-induced potential aerosol formation in a suburban deciduous forest

    Science.gov (United States)

    Nakayama, T.; Kuruma, Y.; Matsumi, Y.; Morino, Y.; Sato, K.; Tsurumaru, H.; Ramasamy, S.; Sakamoto, Y.; Kato, S.; Miyazaki, Y.; Mochizuki, T.; Kawamura, K.; Sadanaga, Y.; Nakashima, Y.; Matsuda, K.; Kajii, Y.

    2017-12-01

    As a new approach to investigating formation processes of secondary organic aerosol (SOA) in the atmosphere, ozone-induced potential aerosol formation was measured in summer at a suburban forest site surrounded by deciduous trees, near Tokyo, Japan. After passage through a reactor containing high concentrations of ozone, increases in total particle volume (average of 1.4 × 109 nm3/cm3, which corresponds to 17% that of pre-existing particles) were observed, especially during daytime. The observed aerosol formations were compared with the results of box model simulations using simultaneously measured concentrations of gaseous and particulate species. According to the model, the relative contributions of isoprene, monoterpene, and aromatic hydrocarbon oxidation to SOA formation in the reactor were 24, 21, and 55%, respectively. However, the model could explain, on average, only ∼40% of the observed particle formation, and large discrepancies between the observations and model were found, especially around noon and in the afternoon when the concentrations of isoprene and oxygenated volatile organic compounds were high. The results suggest a significant contribution of missing (unaccounted-for) SOA formation processes from identified and/or unidentified volatile organic compounds, especially those emitted during daytime. Further efforts should be made to explore and parameterize this missing SOA formation to assist in the improvement of atmospheric chemistry and climate models.

  5. 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.

  6. Hydrologic response to and recovery from differing silvicultural systems in a deciduous forest landscape with seasonal snow cover

    Science.gov (United States)

    Buttle, J. M.; Beall, F. D.; Webster, K. L.; Hazlett, P. W.; Creed, I. F.; Semkin, R. G.; Jeffries, D. S.

    2018-02-01

    Hydrological consequences of alternative harvesting strategies in deciduous forest landscapes with seasonal snow cover have received relatively little attention. Most forest harvesting experiments in landscapes with seasonal snow cover have focused on clearcutting in coniferous forests. Few have examined alternative strategies such as selection or shelterwood cutting in deciduous stands whose hydrologic responses to harvesting may differ from those of conifers. This study presents results from a 31-year examination of hydrological response to and recovery from alternative harvesting strategies in a deciduous forest landscape with seasonal snow cover in central Ontario, Canada. A quantitative means of assessing hydrologic recovery to harvesting is also developed. Clearcutting resulted in increased water year (WY) runoff. This was accompanied by increased runoff in all seasons, with greatest relative increases in Summer. Direct runoff and baseflow from treatment catchments generally increased following harvesting, although annual peak streamflow did not. Largest increases in WY runoff and seasonal runoff as well as direct runoff and baseflow generally occurred in the selection harvest catchment, likely as a result of interception of hillslope runoff by a forest access road and redirection to the stream channel. Hydrologic recovery appeared to begin towards the end of the experimental period for several streamflow metrics but was incomplete for all harvesting strategies 15 years after harvesting. Geochemical tracing indicated that harvesting enhanced the relative importance of surface and near-surface water pathways on catchment slopes for all treatments, with the clearcut catchment showing the most pronounced and prolonged response. Such insights into water partitioning between flow pathways may assist assessments of the ecological and biogeochemical consequences of forest disturbance.

  7. Soil organic matter composition and quality across fire severity gradients in coniferous and deciduous forests of the southern boreal region

    Science.gov (United States)

    Miesel, Jessica R.; Hockaday, William C.; Kolka, Randall K.; Townsend, Philip A.

    2015-06-01

    Recent patterns of prolonged regional drought in southern boreal forests of the Great Lakes region, USA, suggest that the ecological effects of disturbance by wildfire may become increasingly severe. Losses of forest soil organic matter (SOM) during fire can limit soil nutrient availability and forest regeneration. These processes are also influenced by the composition of postfire SOM. We sampled the forest floor layer (i.e., full organic horizon) and 0-10 cm mineral soil from stands dominated by coniferous (Pinus banksiana Lamb.) or deciduous (Populus tremuloides Michx.) species 1-2 months after the 2011 Pagami Creek wildfire in northern Minnesota. We used solid-state 13C NMR to characterize SOM composition across a gradient of fire severity in both forest cover types. SOM composition was affected by fire, even when no statistically significant losses of total C stocks were evident. The most pronounced differences in SOM composition between burned and unburned reference areas occurred in the forest floor for both cover types. Carbohydrate stocks in forest floor and mineral horizons decreased with severity level in both cover types, whereas pyrogenic C stocks increased with severity in the coniferous forest floor and decreased in only the highest severity level in the deciduous forest floor. Loss of carbohydrate and lignin pools contributed to a decreased SOM stability index and increased decomposition index. Our results suggest that increases in fire severity expected to occur under future climate scenarios may lead to changes in SOM composition and dynamics with consequences for postfire forest recovery and C uptake.

  8. Long-term litter manipulation alters soil organic matter turnover in a temperate deciduous forest.

    Science.gov (United States)

    Wang, Jun-Jian; Pisani, Oliva; Lin, Lisa H; Lun, Olivia O Y; Bowden, Richard D; Lajtha, Kate; Simpson, André J; Simpson, Myrna J

    2017-12-31

    Understanding soil organic matter (OM) biogeochemistry at the molecular-level is essential for assessing potential impacts from management practices and climate change on shifts in soil carbon storage. Biomarker analyses and nuclear magnetic resonance (NMR) spectroscopy were used in an ongoing detrital input and removal treatment experiment in a temperate deciduous forest in Pennsylvania, USA, to examine how above- and below-ground plant inputs control soil OM quantity and quality at the molecular-level. From plant material to surface soils, the free acyclic lipids and cutin, suberin, and lignin biomarkers were preferentially retained over free sugars and free cyclic lipids. After 20years of above-ground litter addition (Double Litter) or exclusion (No Litter) treatments, soil OM composition was relatively more degraded, as revealed by solid-state 13 C NMR spectroscopy. Under Doubled Litter inputs, soil carbon and phospholipid fatty acid (PLFA) concentrations were unchanged, suggesting that the current OM degradation status is a reflection of microbial-mediated degradation that occurred prior to the 20-year sampling campaign. Soil OM degradation was higher in the No Litter treatments, likely due to the decline in fresh, above-ground litter inputs over time. Furthermore, root and root and litter exclusion treatments (No Roots and No Inputs, respectively) both significantly reduced free sugars and PLFAs and increased preservation of suberin-derived compounds. PLFA stress ratios and the low N-acetyl resonances from diffusion edited 1 H NMR also indicate substrate limitations and reduced microbial biomass with these treatments. Overall, we highlight that storage of soil carbon and its biochemical composition do not linearly increase with plant inputs because the microbial processing of soil OM is also likely altered in the studied forest. Copyright © 2017 Elsevier B.V. All rights reserved.

  9. 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

  10. Effects of climate variability and functional changes on carbon cycling in a temperate deciduous forest

    Energy Technology Data Exchange (ETDEWEB)

    Wu, Jian

    2013-03-15

    Temperate forests are globally important carbon (C) stocks and sinks. A decadal (1997-2009) trend of increasing C uptake has been observed in an intensively studied temperate deciduous forest, Soroe (Zealand, Denmark). This gave the impetus to investigate the factors controlling the C cycling and the fundamental processes at work in this type of ecosystem. The major objectives of this study were to (1) evaluate to what extent and at what temporal scales, direct climatic variability and functional changes (e.g. changes in the structure or physiological properties) regulate the interannual variability (IAV) in the ecosystem C balance; (2) provide a synthesis of the ecosystem C budget at this site and (3) investigate whether terrestrial ecosystem models can dynamically simulate the trend of increasing C uptake. Data driven analysis, semi-empirical and process-based modelling experiments were performed in a series of studies in order to provide a complete assessment of the carbon storage and allocation within the ecosystem and clarify the mechanisms responsible for the observed variability and trend in the ecosystem C fluxes. Combining all independently estimated ecosystem carbon budget (ECB) datasets and other calculated ECB components based on mass balance equations, a synthesis of the carbon cycling was performed. The results showed that this temperature deciduous forest was moderately productive with both high rates of gross primary production and ecosystem respiration. Approximately 62% of the gross assimilated carbon was respired by the living plants, while 21% was contributed to the soil as litter production, the latter balancing the total heterotrophic respiration. The remaining 17% was either stored in the plants (mainly as aboveground biomass) or removed from the system as wood production. In general, the ECB component datasets were consistent after the cross-checking. This, together with their characterized uncertainties, can be used in model data fusion

  11. Comparative seasonal variations of spectral signatures of broad-leaved and coniferous stands from Landsat data. Comparison with other perennial environments

    International Nuclear Information System (INIS)

    Chaume, R.; Combeau, A.

    1984-01-01

    Spectral signatures of two distinct forest test areas were identified from digital data including 15 LANDSAT scenes covering the same geographical area: a broad-leaved forest (oak and beech) and a coniferous forest (scotch pine). Seasonal variations of the signatures were examined and were expressed in terms of various data: date, solar height and phenological state of vegetation cover. Results were compared to these obtained from other perennial surface conditions (grassland, bare soils) . Range of the seasonal variations of radiance is noted, as well as evolutionary peculiarities on each band and between themes. Rationing of spectral bands (particularly MSS 5 and 7) and their variation with time are specified [fr

  12. 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...

  13. 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

  14. Occurrence of culturable soil fungi in a tropical moist deciduous forest Similipal Biosphere Reserve, Odisha, India.

    Science.gov (United States)

    Jena, Santanu K; Tayung, Kumanand; Rath, Chandi C; Parida, Debraj

    2015-03-01

    Similipal Biosphere Reserve (SBR) is a tropical moist deciduous forest dominated by the species Shorea robusta . To the best of our knowledge their rich biodiversity has not been explored in term of its microbial wealth. In the present investigation, soil samples were collected from ten selected sites inside SBR and studied for their physicochemical parameters and culturable soil fungal diversity. The soil samples were found to be acidic in nature with a pH ranging from of 5.1-6.0. Highest percentage of organic carbon and moisture content were observed in the samples collected from the sites, Chahala-1 and Chahala-2. The plate count revealed that fungal population ranged from 3.6 × 10 (4) -2.1 × 10 (5) and 5.1 × 10 (4) -4.7 × 10 (5) cfu/gm of soil in summer and winter seasons respectively. The soil fungus, Aspergillus niger was found to be the most dominant species and Species Important Values Index (SIVI) was 43.4 and 28.6 in summer and winter seasons respectively. Among the sites studied, highest fungal diversity indices were observed during summer in the sites, Natto-2 and Natto-1. The Shannon-Wiener and Simpson indices in these two sites were found to be 3.12 and 3.022 and 0.9425 and 0.9373 respectively. However, the highest Fisher's alpha was observed during winter in the sites Joranda, Natto-2, Chahala-1 and Natto-1 and the values were 3.780, 3.683, 3.575 and 3.418 respectively. Our investigation revealed that, fungal population was dependent on moisture and organic carbon (%) of the soil but its diversity was found to be regulated by sporulating species like Aspergillus and Penicillium.

  15. Influence of temperature and organic matter content on soil respiration in a deciduous oak forest

    Directory of Open Access Journals (Sweden)

    Zsolt Kotroczó

    2014-12-01

    Full Text Available The increasing temperature enhances soil respiration differently depend on different conditions (soil moisture, soil organic matter, the activity of soil microbes. It is an essential factor to predicting the effect of climate change on soil respiration. In a temperate deciduous forest (North-Hungary we added or removal aboveground and belowground litter to determine total soil respiration. We investigated the relationship between total soil CO2 efflux, soil moisture and soil temperature. Soil CO2 efflux was measured at each plot using chamber based soil respiration measurements. We determined the temperature sensitivity of soil respiration. The effect of doubled litter was less than the effect of removal. We found that temperature was more influential in the control of soil respiration than soil moisture in litter removal treatments, particularly in the wetter root exclusion treatments (NR and NI (R2: 0.49-0.61. Soil moisture (R2: 0.18-0.24 and temperature (R2: 0.18-0.20 influenced soil respiration similarly in treatments, where soil was drier (Control, Double Litter, Double Wood. A significantly greater increase in temperature induced higher soil respiration were significantly higher (2-2.5-fold in root exclusion treatments, where soil was wetter throughout the year, than in control and litter addition treatments. The highest bacterial and fungal count was at the DL treatment but the differences is not significant compared to the Control. The bacterial number at the No Litter, No Root, No Input treatment was significantly lower at the Control. Similar phenomenon can be observed at the fungal too, but the differences are not significant. The results of soil respiration suggest that the soil aridity can reduce soil respiration increases with the temperature increase. Soil bacterial and fungal count results show the higher organic matter content and soil surface cover litter favors the activity.

  16. Temporal variations of atmospheric CO2 concentration in a temperate deciduous forest in central Japan

    International Nuclear Information System (INIS)

    Murayama, Shohei; Saigusa, Nobuko; Yamamoto, Susumu; Kondo, Hiroaki; Eguchi, Yozo; Chan, Douglas

    2003-01-01

    In order to examine the temporal variation of the atmospheric CO 2 concentration in a temperate deciduous forest, and its relationship with meteorological conditions, continuous measurements of CO 2 and meteorological parameters have been made since 1993 on a tower at Takayama in the central part of Japan. In addition to an average secular increase in atmospheric CO 2 of 1.8 ppm/yr, diurnal variation with a maximum during the night-time to early morning and a minimum in the afternoon is observed from late spring to early fall; the diurnal cycle is not so clearly observed in the remaining seasons of the year. A concentration difference between above and below the canopy, and its diurnal variation, can also be seen clearly in summer. Daily mean concentration data show a prominent seasonal cycle. The maximum and the minimum of the seasonal cycle occur in April and from mid August to mid September, respectively. Day-to-day changes in the diurnal cycle of CO 2 are highly dependent on the day-to-day variations in meteorological conditions. However, CO 2 variations on longer time scales (>10 d) appear to be linearly related to changes in respiration. At Takayama, variations in the 10-d standard deviation of daily mean CO 2 data and 10-d averaged respiration show distinct relationships with soil temperature during spring and fall seasons. In spring, respiration has a stronger exponential dependence on soil temperature than in fall. Interestingly, in summer when soil temperature becomes greater than about 15 deg C, biological respiration becomes more variable and independent of the soil temperature. Thus, at the Takayama site, the Q10 relationship is seasonally dependent, and does not represent well the biological respiration process when the soil temperature rises above 15 deg C

  17. Occurrence of culturable soil fungi in a tropical moist deciduous forest Similipal Biosphere Reserve, Odisha, India

    Science.gov (United States)

    Jena, Santanu K.; Tayung, Kumanand; Rath, Chandi C.; Parida, Debraj

    2015-01-01

    Similipal Biosphere Reserve (SBR) is a tropical moist deciduous forest dominated by the species Shorea robusta . To the best of our knowledge their rich biodiversity has not been explored in term of its microbial wealth. In the present investigation, soil samples were collected from ten selected sites inside SBR and studied for their physicochemical parameters and culturable soil fungal diversity. The soil samples were found to be acidic in nature with a pH ranging from of 5.1–6.0. Highest percentage of organic carbon and moisture content were observed in the samples collected from the sites, Chahala-1 and Chahala-2. The plate count revealed that fungal population ranged from 3.6 × 10 4 –2.1 × 10 5 and 5.1 × 10 4 –4.7 × 10 5 cfu/gm of soil in summer and winter seasons respectively. The soil fungus, Aspergillus niger was found to be the most dominant species and Species Important Values Index (SIVI) was 43.4 and 28.6 in summer and winter seasons respectively. Among the sites studied, highest fungal diversity indices were observed during summer in the sites, Natto-2 and Natto-1. The Shannon-Wiener and Simpson indices in these two sites were found to be 3.12 and 3.022 and 0.9425 and 0.9373 respectively. However, the highest Fisher’s alpha was observed during winter in the sites Joranda, Natto-2, Chahala-1 and Natto-1 and the values were 3.780, 3.683, 3.575 and 3.418 respectively. Our investigation revealed that, fungal population was dependent on moisture and organic carbon (%) of the soil but its diversity was found to be regulated by sporulating species like Aspergillus and Penicillium . PMID:26221092

  18. Occurrence of culturable soil fungi in a tropical moist deciduous forest Similipal Biosphere Reserve, Odisha, India

    Directory of Open Access Journals (Sweden)

    Santanu K. Jena

    2015-03-01

    Full Text Available Similipal Biosphere Reserve (SBR is a tropical moist deciduous forest dominated by the species Shorea robusta. To the best of our knowledge their rich biodiversity has not been explored in term of its microbial wealth. In the present investigation, soil samples were collected from ten selected sites inside SBR and studied for their physicochemical parameters and culturable soil fungal diversity. The soil samples were found to be acidic in nature with a pH ranging from of 5.1–6.0. Highest percentage of organic carbon and moisture content were observed in the samples collected from the sites, Chahala-1 and Chahala-2. The plate count revealed that fungal population ranged from 3.6 × 104–2.1 × 105 and 5.1 × 104–4.7 × 105 cfu/gm of soil in summer and winter seasons respectively. The soil fungus, Aspergillus niger was found to be the most dominant species and Species Important Values Index (SIVI was 43.4 and 28.6 in summer and winter seasons respectively. Among the sites studied, highest fungal diversity indices were observed during summer in the sites, Natto-2 and Natto-1. The Shannon-Wiener and Simpson indices in these two sites were found to be 3.12 and 3.022 and 0.9425 and 0.9373 respectively. However, the highest Fisher’s alpha was observed during winter in the sites Joranda, Natto-2, Chahala-1 and Natto-1 and the values were 3.780, 3.683, 3.575 and 3.418 respectively. Our investigation revealed that, fungal population was dependent on moisture and organic carbon (% of the soil but its diversity was found to be regulated by sporulating species like Aspergillus and Penicillium.

  19. Carbon Sequestration of Caesalpinia platyloba S. Watt (Leguminosae) (Lott 1985) in the Tropical Deciduous Forest

    Science.gov (United States)

    Diaz-Gustavo, Norma; Martínez-Salvador, Martín; García-Hernández, José Luís; Norzagaray-Campos, Mariano; Luna-González, Antonio; González-Ocampo, Héctor Abelardo

    2015-01-01

    Caesalpinia platyloba was evaluated as an alternative for the retention of atmospheric carbon and as a feasible and viable economic activity in terms of income for tropical deciduous forest (TDF) peasants in the carbon markets. A total of 110 trees of C. platyloba from plantations and a TDF in the Northwest of Mexico were sampled. Growth (increase in height, diameter, and volume curves) was adjusted to assess their growth. Growth of individuals (height, diameter at breast height [DBH], age, and tree crown cover) was recorded. The Schumacher model (H = β 0 e β1•E-1), by means of the guided curve method, was used to adjust growth models. Information analysis was made through the non-linear procedure with the multivariate secant or false position (DUD) method using the SAS software. Growth and increase models revealed acceptable adjustments (pseudo R2>0.8). C. platyloba reaches >8m of height with 12cm in diameter and 550cm3 of volume, presenting the highest increase at 11 years considered as basal age. Highest significant density of wood was in good quality sites (0.80g•cm-3), with a carbon content (average of 99.15tC•ha-1) at the highest density of 2500 trees•ha-1 (without thinning). Average incomes of US$483.33tC•ha-1 are expected. The profitability values (NPW = US$81,646.65, IRR = 472%, and B/C = 0.82) for C. platyloba make its cultivation a viable and profitable activity, considering a management scheme of the income derived from wood selling and from carbon credits. PMID:25992905

  20. 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.

  1. 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.

  2. Forest type effects on the retention of radiocesium in organic layers of forest ecosystems affected by the Fukushima nuclear accident

    Science.gov (United States)

    Koarashi, Jun; Atarashi-Andoh, Mariko; Matsunaga, Takeshi; Sanada, Yukihisa

    2016-12-01

    The Fukushima Daiichi nuclear power plant disaster caused serious radiocesium (137Cs) contamination of forest ecosystems over a wide area. Forest-floor organic layers play a key role in controlling the overall bioavailability of 137Cs in forest ecosystems; however, there is still an insufficient understanding of how forest types influence the retention capability of 137Cs in organic layers in Japanese forest ecosystems. Here we conducted plot-scale investigations on the retention of 137Cs in organic layers at two contrasting forest sites in Fukushima. In a deciduous broad-leaved forest, approximately 80% of the deposited 137Cs migrated to mineral soil located below the organic layers within two years after the accident, with an ecological half-life of approximately one year. Conversely, in an evergreen coniferous forest, more than half of the deposited 137Cs remained in the organic layers, with an ecological half-life of 2.1 years. The observed retention behavior can be well explained by the tree phenology and accumulation of 137Cs associated with litter materials with different degrees of degradation in the organic layers. Spatial and temporal patterns of gamma-ray dose rates depended on the retention capability. Our results demonstrate that enhanced radiation risks last longer in evergreen coniferous forests than in deciduous broad-leaved forests.

  3. 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.

  4. 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

  5. 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

    International Nuclear Information System (INIS)

    Boggs, Johnny L.; McNulty, Steven G.; Pardo, Linda H.

    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, we observed a significant correlation between mean growing season temperature and red spruce basal area growth. Red spruce and deciduous foliar %N correlated significantly with N deposition. Although N deposition has not changed significantly from 1987/1988 to 1999, net nitrification potential decreased significantly at Whiteface. This decrease in net potential nitrification is not consistent with the N saturation hypothesis and suggests that non-N deposition controls, such as climatic factors and immobilization of down dead wood, might have limited N cycling. - Data from the 1999 remeasurement of the red spruce forests suggest that N deposition, to some extent, is continuing to influence red spruce across the northeastern US as illustrated by a significant correlation between N deposition and red spruce foliar %N. Our data also suggest that the decrease in forest floor %N and net nitrification potential across sites from 1987 to 1999 may be due to factors other than N deposition, such as climatic factors and N immobilization in fine woody material (<5 cm diameter)

  6. EFFECTS OF LAND-USE CHANGE ON THE PROPERTIES OF TOP SOIL OF DECIDUOUS SAL FOREST IN BANGLADESH

    Directory of Open Access Journals (Sweden)

    M. A. Kashem

    2016-08-01

    Full Text Available This study examined the effects of land use change on the physico-chemical properties of top soil in the deciduous Sal forest of Bangladesh. Relatively less disturbed Sal (Shorea robusta Roxb. Ex Gaertn. forest stands and the nearby stands those were converted into Acacia (Acacia auriculiformis Benth. plantation and pineapple (Ananus comosus (L. Merr. cultivation were selected to examine the effects of land use change on soil properties. For each land use type, soil samples were collected from 4 locations, 50m distant from each other, as replicates. Soil samples were collected at 0-5, 5-10, and 10-15 cm depths. Soil moisture content, conductivity, pH organic C, total N and total P were determined as soil properties. Leaf litter of Sal, Acacia and pineapple was incubation for 90 and 180 days in independent identical soil in order to examine the effects of plant species through leaf litter on the soil chemical nutrient (N and P status. Data showed that soil moisture content, conductivity and pH were significantly affected by land use but not by depth. However, soil organic C was affected by both land-use type (P< 0.02 and soil depth (P< 0.003, although no significant interactions appeared between these two factors. Soil total N and P did not differ between land use types but by depth and, N and P contents decreased with the increase of depth. Rates of nutrients (N and P released from Sal, Acacia and pineapple did not differ significantly among them during incubation. Results of the present study reveal that properties of the top soil of the Madhupur Sal forest are different in their responses to the varying land uses. The findings of this study are thus relevant for the sustainable management of the deciduous Sal forest ecosystems.

  7. Ecosystem-Atmosphere Exchange of Carbon, Water and Energy over a Mixed Deciduous Forest in the Midwest

    Energy Technology Data Exchange (ETDEWEB)

    Danilo Dragoni; Hans Peter Schmid; C.S.B. Grimmond; J.C. Randolph; J.R. White

    2012-12-17

    During the project period we continued to conduct long-term (multi-year) measurements, analysis, and modeling of energy and mass exchange in and over a deciduous forest in the Midwestern United States, to enhance the understanding of soil-vegetation-atmosphere exchange of carbon. At the time when this report was prepared, results from nine years of measurements (1998 - 2006) of above canopy CO2 and energy fluxes at the AmeriFlux site in the Morgan-Monroe State Forest, Indiana, USA (see Table 1), were available on the Fluxnet database, and the hourly CO2 fluxes for 2007 are presented here (see Figure 1). The annual sequestration of atmospheric carbon by the forest is determined to be between 240 and 420 g C m-2 a-1 for the first ten years. These estimates are based on eddy covariance measurements above the forest, with a gap-filling scheme based on soil temperature and photosynthetically active radiation. Data gaps result from missing data or measurements that were rejected in qua)lity control (e.g., during calm nights). Complementary measurements of ecological variables (i.e. inventory method), provided an alternative method to quantify net carbon uptake by the forest, partition carbon allocation in each ecosystem components, and reduce uncertainty on annual net ecosystem productivity (NEP). Biometric datasets are available on the Fluxnext database since 1998 (with the exclusion of 2006). Analysis for year 2007 is under completion.

  8. Landscape composition influences abundance patterns and habitat use of three ungulate species in fragmented secondary deciduous tropical forests, Mexico

    Directory of Open Access Journals (Sweden)

    G. García-Marmolejo

    2015-01-01

    Full Text Available Secondary forests are extensive in the tropics. Currently, these plant communities are the available habitats for wildlife and in the future they will possibly be some of the most wide-spread ecosystems world-wide. To understand the potential role of secondary forests for wildlife conservation, three ungulate species were studied: Mazama temama, Odocoileus virginianus and Pecari tajacu. We analyzed their relative abundance and habitat use at two spatial scales: (1 Local, where three different successional stages of tropical deciduous forest were compared, and (2 Landscape, where available habitats were compared in terms of landscape composition (proportion of forests, pastures and croplands within 113 ha. To determine the most important habitat-related environmental factors influencing the Sign Encounter Rate (SER of the three ungulate species, 11 physical, anthropogenic and vegetation variables were simultaneously analyzed through model selection using Akaike’s Information Criterion. We found, that P. tajacu and O. virginianus mainly used early successional stages, while M. temama used all successional stages in similar proportions. The latter species, however, used early vegetation stages only when they were located in landscapes mainly covered by forest (97%. P. tajacu and O. virginianus also selected landscapes covered essentially by forests, although they required smaller percentages of forest (86%. All ungulate species avoided landscape fragments covered by pastures. For all three species, landscape composition and human activities were the variables that best explained SER. We concluded that landscape is the fundamental scale for ungulate management, and that secondary forests are potentially important landscape elements for ungulate conservation.

  9. Scaling wood volume estimates from inventory plots to landscapes with airborne LiDAR in temperate deciduous forest

    Directory of Open Access Journals (Sweden)

    Shaun R. Levick

    2016-05-01

    Full Text Available Abstract Background Monitoring and managing carbon stocks in forested ecosystems requires accurate and repeatable quantification of the spatial distribution of wood volume at landscape to regional scales. Grid-based forest inventory networks have provided valuable records of forest structure and dynamics at individual plot scales, but in isolation they may not represent the carbon dynamics of heterogeneous landscapes encompassing diverse land-management strategies and site conditions. Airborne LiDAR has greatly enhanced forest structural characterisation and, in conjunction with field-based inventories, it provides avenues for monitoring carbon over broader spatial scales. Here we aim to enhance the integration of airborne LiDAR surveying with field-based inventories by exploring the effect of inventory plot size and number on the relationship between field-estimated and LiDAR-predicted wood volume in deciduous broad-leafed forest in central Germany. Results Estimation of wood volume from airborne LiDAR was most robust (R2 = 0.92, RMSE = 50.57 m3 ha−1 ~14.13 Mg C ha−1 when trained and tested with 1 ha experimental plot data (n = 50. Predictions based on a more extensive (n = 1100 plot network with considerably smaller (0.05 ha plots were inferior (R2 = 0.68, RMSE = 101.01 ~28.09 Mg C ha−1. Differences between the 1 and 0.05 ha volume models from LiDAR were negligible however at the scale of individual land-management units. Sample size permutation tests showed that increasing the number of inventory plots above 350 for the 0.05 ha plots returned no improvement in R2 and RMSE variability of the LiDAR-predicted wood volume model. Conclusions Our results from this study confirm the utility of LiDAR for estimating wood volume in deciduous broad-leafed forest, but highlight the challenges associated with field plot size and number in establishing robust relationships between airborne LiDAR and field derived wood volume. We

  10. Scaling wood volume estimates from inventory plots to landscapes with airborne LiDAR in temperate deciduous forest.

    Science.gov (United States)

    Levick, Shaun R; Hessenmöller, Dominik; Schulze, E-Detlef

    2016-12-01

    Monitoring and managing carbon stocks in forested ecosystems requires accurate and repeatable quantification of the spatial distribution of wood volume at landscape to regional scales. Grid-based forest inventory networks have provided valuable records of forest structure and dynamics at individual plot scales, but in isolation they may not represent the carbon dynamics of heterogeneous landscapes encompassing diverse land-management strategies and site conditions. Airborne LiDAR has greatly enhanced forest structural characterisation and, in conjunction with field-based inventories, it provides avenues for monitoring carbon over broader spatial scales. Here we aim to enhance the integration of airborne LiDAR surveying with field-based inventories by exploring the effect of inventory plot size and number on the relationship between field-estimated and LiDAR-predicted wood volume in deciduous broad-leafed forest in central Germany. Estimation of wood volume from airborne LiDAR was most robust (R 2  = 0.92, RMSE = 50.57 m 3 ha -1  ~14.13 Mg C ha -1 ) when trained and tested with 1 ha experimental plot data (n = 50). Predictions based on a more extensive (n = 1100) plot network with considerably smaller (0.05 ha) plots were inferior (R 2  = 0.68, RMSE = 101.01 ~28.09 Mg C ha -1 ). Differences between the 1 and 0.05 ha volume models from LiDAR were negligible however at the scale of individual land-management units. Sample size permutation tests showed that increasing the number of inventory plots above 350 for the 0.05 ha plots returned no improvement in R 2 and RMSE variability of the LiDAR-predicted wood volume model. Our results from this study confirm the utility of LiDAR for estimating wood volume in deciduous broad-leafed forest, but highlight the challenges associated with field plot size and number in establishing robust relationships between airborne LiDAR and field derived wood volume. We are moving into a forest management era where

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

    Directory of Open Access Journals (Sweden)

    GERUZA L. MELO

    2013-06-01

    Full Text Available 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.Cada espécie animal pode apresentar seletividade por micro-habitats priorizando proteção, forrageio ou microclima. Para compreender os padrões de distribuição de pequenos mamíferos ao nível do solo e de sub-bosque, nós analisamos o uso de micro-habitat por pequenos mamíferos em uma floresta estacional no sul do Brasil. Dez estações amostrais com sete pontos de captura foram usadas para amostragem dos seguintes microhabitats: liana, tronco caído, solo apenas coberto por folhiço, solo coberto por samambaias, árvore com tronco simples, árvore com bifurcações e arbustos do g

  12. 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.

  13. 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...

  14. Seed morphology, germination phenology, and capacity to form a seed bank in six herbaceous layer apiaceae species of the eastern deciduous forest

    Science.gov (United States)

    Tracy S. Hawkins; Jerry M. Baskin; Carol C. Baskin

    2007-01-01

    We compared seed mass, seed morphology, and long-term germination phenology of three monocarpic (MI and three polycarpic (P) Apiaceae species of the herbaceous layer of the Eastern Deciduous Forest. Seeds (mericarps) of the six species differed considerably in mass, shape, and ornamentation. Mean seed masses were ranked Cryptotaenia canadensis (M)...

  15. Seed longevity and dormancy state suggest management strategies for garlic mustard (Alliaria petiolata) and Japanese stiltgrass (Microstegium vimineum) in deciduous forest sites

    Science.gov (United States)

    Mame E. Redwood; Glenn R. Matlack; Cynthia D. Huebner

    2018-01-01

    An effective management plan for invasive herb populations must consider the potential for regeneration from the soil seedbank. To test chis potential, we examined two species, Japanese scilcgrass and garlic mustard, at deciduous forest sites in southeastern Ohio. Seeds were buried in nylon mesh bags and recovered at regular intervals over 24 mo. Recovered seeds were...

  16. 137Cs vertical migration in a deciduous forest soil following the Fukushima Dai-ichi Nuclear Power Plant accident

    International Nuclear Information System (INIS)

    Nakanishi, Takahiro; Matsunaga, Takeshi; Koarashi, Jun; Atarashi-Andoh, Mariko

    2014-01-01

    The large amount of 137 Cs deposited on the forest floor because of the Fukushima Dai-ichi Nuclear Power Plant accident represents a major potential long-term source for mobile 137 Cs. To investigate 137 Cs mobility in forest soils, we investigated the vertical migration of 137 Cs through seepage water, using a lysimetric method. The study was conducted in a deciduous forest soil over a period spanning 2 month to 2 y after the Fukushima nuclear accident. Our observations demonstrated that the major part of 137 Cs in the litter layer moved into the mineral soil within one year after the accident. On the other hand, the topsoil prevented migration of 137 Cs, and only 2% of 137 Cs in the leachate from litter and humus layer penetrated below a 10 cm depth. The annual migration below a 10 cm depth accounted for 0.1% of the total 137 Cs inventory. Therefore, the migration of 137 Cs by seepage water comprised only a very small part of the total 137 Cs inventory in the mineral soil, which was undetectable from the vertical distribution of 137 Cs in the soil profile. In the present and immediate future, most of the 137 Cs deposited on the forest floor will probably remain in the topsoil successively, although a small but certain amount of bioavailable 137 Cs exists in forest surface soil. -- Highlights: • Lysimeter captured 137 Cs mobility in a forest soil after the Fukushima accident. • Major part of 137 Cs in the litter layer moved into the mineral soil within a year. • Litter-leachate 137 Cs was predominantly adsorbed within the topsoil. • The annual migration below a 10 cm depth was 0.1% of the total 137 Cs inventory

  17. 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...

  18. Comparison of vegetation patterns and soil nutrient relations in an oak-pine forest and a mixed deciduous forest on Long Island, New York

    Energy Technology Data Exchange (ETDEWEB)

    Peterson, S.C.; Curtis, P.S.

    1980-11-01

    An analysis of soil nutrient relations in two forest communities on Long Island, NY, yielded a correlation between the fertility of the top-soil and vegetational composition. The oak-pine forest soils at Brookhaven National Laboratory contain lower average concentrations of NH/sub 3/, Ca, K, and organic matter than the mixed deciduous forest soils in the Stony Brook area. The pH of the topsoil is also more acidic at Brookhaven. The observed differences between localities are greater than within-locality differences between the two soil series tested (Plymouth and Riverhead), which are common to both localities. Nutrient concentrations in the subsoil are not consistently correlated with either locality or soil series, although organic matter and NH/sub 3/ show significantly higher concentrations at Stony Brook. Supporting data on density and basal area of trees and coverage of shrubs and herbs also reveals significant variation between the two forest communities. An ordination of the vegetation data shows higher similarity within than between localities, while no obvious pattern of within-locality variation due to soil series treatments is apparent. These data support the hypothesis that fertility gradients may influence forest community composition and structure. This hypothesis is discussed with reference to vegetation-soil interactions and other factors, such as frequency of burning, which may direct the future development of the Brookhaven oak-pine forest.

  19. Effects of a windthrow disturbance on the carbon balance of a broadleaf deciduous forest in Hokkaido, Japan

    Directory of Open Access Journals (Sweden)

    K. Yamanoi

    2015-12-01

    Full Text Available Forests play an important role in the terrestrial carbon balance, with most being in a carbon sequestration stage. The net carbon releases that occur result from forest disturbance, and windthrow is a typical disturbance event affecting the forest carbon balance in eastern Asia. The CO2 flux has been measured using the eddy covariance method in a deciduous broadleaf forest (Japanese white birch, Japanese oak, and castor aralia in Hokkaido, where incidental damage by the strong Typhoon Songda in 2004 occurred. We also used the biometrical method to demonstrate the CO2 flux within the forest in detail. Damaged trees amounted to 40 % of all trees, and they remained on site where they were not extracted by forest management. Gross primary production (GPP, ecosystem respiration (Re, and net ecosystem production were 1350, 975, and 375 g C m−2 yr−1 before the disturbance and 1262, 1359, and −97 g C m−2 yr−1 2 years after the disturbance, respectively. Before the disturbance, the forest was an evident carbon sink, and it subsequently transformed into a net carbon source. Because of increased light intensity at the forest floor, the leaf area index and biomass of the undergrowth (Sasa kurilensis and S. senanensis increased by factors of 2.4 and 1.7, respectively, in 3 years subsequent to the disturbance. The photosynthesis of Sasa increased rapidly and contributed to the total GPP after the disturbance. The annual GPP only decreased by 6 % just after the disturbance. On the other hand, the annual Re increased by 39 % mainly because of the decomposition of residual coarse-wood debris. The carbon balance after the disturbance was controlled by the new growth and the decomposition of residues. The forest management, which resulted in the dead trees remaining at the study site, strongly affected the carbon balance over the years. When comparing the carbon uptake efficiency at the study site with that at others, including those with various kinds

  20. The leaf size-twig size spectrum in evergreen broad- leaved forest of ...

    African Journals Online (AJOL)

    STORAGESEVER

    2010-06-07

    Jun 7, 2010 ... al., 1998; Brouat and McKey, 2001; Preston and Ackerly,. 2003; Westoby and Wright, 2003), few studies have examined the scaling relationship in relation to environ- mental gradients. In order to examine the response of the leaf size-twig size relationship to environmental variations, we investi-.

  1. Predicting the spatial distribution of leaf litterfall in a mixed deciduous forest

    NARCIS (Netherlands)

    Staelens, Jeroen; Nachtergale, Lieven; Luyssaert, Sebastiaan

    2004-01-01

    An accurate prediction of the spatial distribution of litterfall can improve insight in the interaction between the canopy layer and forest floor characteristics, which is a key feature in forest nutrient cycling. Attempts to model the spatial variability of litterfall have been made across forest

  2. 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.

  3. Ecological effects of pipeline construction through deciduous forested wetlands, Midland County, Michigan. Topical report, October 1990--August 1992

    Energy Technology Data Exchange (ETDEWEB)

    Rastorfer, J.R. [Chicago State Univ., IL (United States). Dept. of Biological Sciences; Van Dyke, G.D.; Zellmer, S.D.; Wilkey, P.L. [Argonne National Lab., IL (United States)

    1995-04-01

    This study is designed to record vegetational changes induced by the construction of a large-diameter gas pipeline through deciduous forested wetlands. Two second-growth wetland sites mapped Lenawee soils were selected in Midland County, Michigan: Site 1, a younger stand subjected to recent selective logging, and Site 2, a more mature stand. The collection of ecological data to analyze plant succession on the right-of-way (ROW) and the effects of the developing ROW plant communities on adjacent forest communities was initiated in 1989. Cover class estimates were made for understory and ROW plant species on the basis of 1 {times} 1{minus}m quadrats. Individual stem diameters and species counts were recorded for overstory plants in 10{minus}m quadrats. Although long-term studies have not been completed, firm baseline data were established for comparative analyses with future sampling. Current data indicate that vegetation became well-established on the ROW within one year and subsequently increased in coverage. About 65% of the species were wetland indicators, and the dominants included seeded and natural invading species; nevertheless, some elements of the original flora regenerated and persist. The plants of the ecotone understories of both sites changed from their original composition as a result of the installation of the gas pipeline. Although some forest species persist at both sites, the ecotone of Site I was influenced more by the seeded species, whereas the natural invaders were more important at Site 2.

  4. MODIS-derived EVI, NDVI and WDRVI time series to estimate phenological metrics in French deciduous forests

    Science.gov (United States)

    Testa, S.; Soudani, K.; Boschetti, L.; Borgogno Mondino, E.

    2018-02-01

    Monitoring forest phenology allows us to study the effects of climate change on vegetated land surfaces. Daily and composite time series (TS) of several vegetation indices (VIs) from MODerate resolution Imaging Spectroradiometer (MODIS) data have been widely used in scientific works for phenological studies since the beginning of the MODIS mission. The objective of this work was to use MODIS data to find the best VI/TS combination to estimate start-of-season (SOS) and end-of-season (EOS) dates across 50 temperate deciduous forests. Our research used as inputs 2001-2012 daily reflectance from MOD09GQ/MOD09GA products and 16-day composite VIs from the MOD13Q1 dataset. The 50 pixels centered on the 50 forest plots were extracted from the above-mentioned MODIS imagery; we then generated 5 different types of TS (1 daily from MOD09 and 4 composite from MOD13Q1) and used all of them to implement 6 VIs, obtaining 30 VI/TS combinations. SOS and EOS estimates were determined for each pixel/year and each VI/TS combination. SOS/EOS estimations were then validated against ground phenological observations. Results showed that, in our test areas, composite TS, if actual acquisition date is considered, performed mostly better than daily TS. EVI, WDRVI0.20 and NDVI were more suitable to SOS estimation, while WDRVI0.05 and EVI were more convenient in estimating early and advanced EOS, respectively.

  5. Genetic structure and breeding system of a rare understory herb, Dysosma versipellis (Berberidaceae), from temperate deciduous forests in China.

    Science.gov (United States)

    Guan, Bi-Cai; Fu, Cheng-Xing; Qiu, Ying-Xiong; Zhou, Shi-Liang; Comes, Hans Peter

    2010-01-01

    To evaluate the role of Quaternary refugial isolation in allopatric (incipient) speciation of East Asian temperate forest biotas, we analyzed amplified fragment length polymorphisms (AFLPs) and the breeding system in Dysosma versipellis. The study revealed that D. versipellis is mostly self-incompatible, genetically highly subdivided and depauperate at the population level (e.g., Φ(ST) = 0.572/H(E) = 0.083), and characterized by a low pollen-to-seed migration ratio (r ≈ 4.0). The latter outcome likely reflects limited pollen flow in a low-seed disperser whose hypothesized "sapromyophilous" flowers undergo scarce, inefficient, and likely specialized cross-pollination by small Anoplodera beetles, rather than carrion flies as assumed previously. In consequence, fruit set in D. versipellis was strongly pollen-limited. Our AFLP data support the hypothesis of a long-standing cessation of gene flow between western and central eastern populations, consistent with previous chloroplast DNA data. This phylogeographic pattern supports the role of the Sichuan Basin as a floristic boundary separating the Sino-Himalayan vs. Sino-Japanese Forest subkingdoms. Our genetic data of D. versipellis also imply that temperate deciduous forest elements to the west and the east of this basin responded differently to Quaternary climate change, which may have triggered or is leading to allopatric (incipient) speciation.

  6. On the vertical distribution of bees in a temperate deciduous forest

    Science.gov (United States)

    Michael Ulyshen; Villa Soon; James Hanula

    2010-01-01

    1. Despite a growing interest in forest canopy biology, very few studies have examined the vertical distribution of forest bees. In this study, bees were sampled using 12 pairs of flight-intercept traps suspended in the canopy (‡15 m) and near the ground (0.5 m) in a bottomland hardwood forest in the southeastern United States. 2. In total, 6653 bees from 5 families...

  7. 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

  8. Strategic management of five deciduous forest invaders using Microstegium vimineum as a model species

    Science.gov (United States)

    Cynthia D. Huebner

    2007-01-01

    This paper links key plant invasive traits with key landscape traits to define strategic management for five common forest invaders, using empirical data of Microstegium vimineum dispersal into forests as a preliminary model. Microstegium vimineum exhibits an Allee effect that may allow management to focus on treating its source...

  9. The importance of streamside sandbars to ground beetle (Coleoptera, Carabidae) communities in a deciduous forest.

    Science.gov (United States)

    S. Horn; M.D. Ulyshen

    2009-01-01

    We used pitfall traps to sample ground beetles on sandbars along a small woodland stream and in the adjacent floodplain forest (Oglethorpe Co., GA, USA). We captured a total of 1,477 ground beetles representing 41 species. Twenty-two species were exclusive to sandbars, while eight were found only in the forested habitat. Ground beetles...

  10. Indirect estimations and spatial variation in leaf area index of coniferous, deciduous and mixed forest stands in Forsmark and Laxemar

    International Nuclear Information System (INIS)

    Tagesson, Torbern

    2006-12-01

    Two sites in Sweden are investigated for a potential deep repository of the nuclear waste, the Laxemar investigation area (57 deg 5 min N, 16 deg 7 min E) and the Forsmark investigation area (60 deg 4 min N, 18 deg 2 min E). In the characterisation of these sites, development of site descriptive models is an important part. Leaves are the main surface were an exchange of matter and energy between the atmosphere and the biosphere takes place, and leaf area index (LAI) of the vegetation cover is an important variable correlated to a number of ecophysiological parameters and hereby an important parameter in ecosystem models. In the investigation areas, LAI of boreal and temperate ecosystems were therefore estimated indirectly through optical measurements using the LAI-2000 (LI-COR, Cambridge UK) and TRAC (Tracing Radiation and Architecture of Canopies). On average, measured maximum LAI was 3.40 in Laxemar and 3.43 in Forsmark; minimum LAI was 1.65 in Laxemar and 1.97 in Forsmark. Forest inventory data showed that LAI is positively correlated with basal area, stand height, stand volume and breast height tree diameter. For the coniferous stands, there was also a linearly negative relationship with age. In the Laxemar investigation area, there were no significant relationships for LAI with a satellite derived kNN (kNearest Neighbor) data set with stand height, stand volume and stand age. The kNN data set can therefore not be used to extrapolate measured LAI over the Laxemar investigation area. There were significant relationships between LAI and the normalized difference vegetation index (NDVI) for coniferous, deciduous and mixed forest stands in the Laxemar investigation area. A NDVI image could be used to extrapolate LAI over the entire investigation area. For the Forsmark investigation area, effective LAI for all stands were correlated to NDVI and this relationship could then be used for extrapolation. The effective LAI image was afterwards corrected for average

  11. Indirect estimations and spatial variation in leaf area index of coniferous, deciduous and mixed forest stands in Forsmark and Laxemar

    Energy Technology Data Exchange (ETDEWEB)

    Tagesson, Torbern [Dept. of Physical Geography and Ecosystem Analysis, Lund Univ., Lund (Sweden)

    2006-12-15

    Two sites in Sweden are investigated for a potential deep repository of the nuclear waste, the Laxemar investigation area (57 deg 5 min N, 16 deg 7 min E) and the Forsmark investigation area (60 deg 4 min N, 18 deg 2 min E). In the characterisation of these sites, development of site descriptive models is an important part. Leaves are the main surface were an exchange of matter and energy between the atmosphere and the biosphere takes place, and leaf area index (LAI) of the vegetation cover is an important variable correlated to a number of ecophysiological parameters and hereby an important parameter in ecosystem models. In the investigation areas, LAI of boreal and temperate ecosystems were therefore estimated indirectly through optical measurements using the LAI-2000 (LI-COR, Cambridge UK) and TRAC (Tracing Radiation and Architecture of Canopies). On average, measured maximum LAI was 3.40 in Laxemar and 3.43 in Forsmark; minimum LAI was 1.65 in Laxemar and 1.97 in Forsmark. Forest inventory data showed that LAI is positively correlated with basal area, stand height, stand volume and breast height tree diameter. For the coniferous stands, there was also a linearly negative relationship with age. In the Laxemar investigation area, there were no significant relationships for LAI with a satellite derived kNN (kNearest Neighbor) data set with stand height, stand volume and stand age. The kNN data set can therefore not be used to extrapolate measured LAI over the Laxemar investigation area. There were significant relationships between LAI and the normalized difference vegetation index (NDVI) for coniferous, deciduous and mixed forest stands in the Laxemar investigation area. A NDVI image could be used to extrapolate LAI over the entire investigation area. For the Forsmark investigation area, effective LAI for all stands were correlated to NDVI and this relationship could then be used for extrapolation. The effective LAI image was afterwards corrected for average

  12. Hypholoma lateritium isolated from coarse woody debris, the forest floor, and mineral soil in a deciduous forest in New Hampshire

    Science.gov (United States)

    Therese A. Thompson; R. Greg Thorn; Kevin T. Smith

    2012-01-01

    Fungi in the Agaricomycetes (Basidiomycota) are the primary decomposers in temperate forests of dead wood on and in the forest soil. Through the use of isolation techniques selective for saprotrophic Agaricomycetes, a variety of wood decay fungi were isolated from a northern hardwood stand in the Bartlett Experimental Forest, New Hampshire, USA. In particular,

  13. The Atmospheric Chemistry and Canopy Exchange Simulation System (ACCESS: model description and application to a temperate deciduous forest canopy

    Directory of Open Access Journals (Sweden)

    R. D. Saylor

    2013-01-01

    Full Text Available Forest canopies are primary emission sources of biogenic volatile organic compounds (BVOCs and have the potential to significantly influence the formation and distribution of secondary organic aerosol (SOA mass. Biogenically-derived SOA formed as a result of emissions from the widespread forests across the globe may affect air quality in populated areas, degrade atmospheric visibility, and affect climate through direct and indirect forcings. In an effort to better understand the formation of SOA mass from forest emissions, a 1-D column model of the multiphase physical and chemical processes occurring within and just above a vegetative canopy is being developed. An initial, gas-phase-only version of this model, the Atmospheric Chemistry and Canopy Exchange Simulation System (ACCESS, includes processes accounting for the emission of BVOCs from the canopy, turbulent vertical transport within and above the canopy and throughout the height of the planetary boundary layer (PBL, near-explicit representation of chemical transformations, mixing with the background atmosphere and bi-directional exchange between the atmosphere and canopy and the atmosphere and forest floor. The model formulation of ACCESS is described in detail and results are presented for an initial application of the modeling system to Walker Branch Watershed, an isoprene-emission-dominated forest canopy in the southeastern United States which has been the focal point for previous chemical and micrometeorological studies. Model results of isoprene profiles and fluxes are found to be consistent with previous measurements made at the simulated site and with other measurements made in and above mixed deciduous forests in the southeastern United States. Sensitivity experiments are presented which explore how canopy concentrations and fluxes of gas-phase precursors of SOA are affected by background anthropogenic nitrogen oxides (NOx. Results from these experiments suggest that the

  14. 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.

  15. Acidotolerant Bacteria and Fungi as a Sink of Methanol-Derived Carbon in a Deciduous Forest Soil

    Directory of Open Access Journals (Sweden)

    Mareen Morawe

    2017-07-01

    Full Text Available Methanol is an abundant atmospheric volatile organic compound that is released from both living and decaying plant material. In forest and other aerated soils, methanol can be consumed by methanol-utilizing microorganisms that constitute a known terrestrial sink. However, the environmental factors that drive the biodiversity of such methanol-utilizers have been hardly resolved. Soil-derived isolates of methanol-utilizers can also often assimilate multicarbon compounds as alternative substrates. Here, we conducted a comparative DNA stable isotope probing experiment under methylotrophic (only [13C1]-methanol was supplemented and combined substrate conditions ([12C1]-methanol and alternative multi-carbon [13Cu]-substrates were simultaneously supplemented to (i identify methanol-utilizing microorganisms of a deciduous forest soil (European beech dominated temperate forest in Germany, (ii assess their substrate range in the soil environment, and (iii evaluate their trophic links to other soil microorganisms. The applied multi-carbon substrates represented typical intermediates of organic matter degradation, such as acetate, plant-derived sugars (xylose and glucose, and a lignin-derived aromatic compound (vanillic acid. An experimentally induced pH shift was associated with substantial changes of the diversity of active methanol-utilizers suggesting that soil pH was a niche-defining factor of these microorganisms. The main bacterial methanol-utilizers were members of the Beijerinckiaceae (Bacteria that played a central role in a detected methanol-based food web. A clear preference for methanol or multi-carbon substrates as carbon source of different Beijerinckiaceae-affiliated phylotypes was observed suggesting a restricted substrate range of the methylotrophic representatives. Apart from Bacteria, we also identified the yeasts Cryptococcus and Trichosporon as methanol-derived carbon-utilizing fungi suggesting that further research is needed to

  16. Mercury concentrations and pools in four adjacent coniferous and deciduous upland forests in Beijing, China

    Science.gov (United States)

    Zhou, Jun; Wang, Zhangwei; Zhang, Xiaoshan; Gao, Yu

    2017-05-01

    Understanding of forest mercury (Hg) pools is important for quantifying the global atmospheric Hg removal. We studied gaseous elemental Hg (GEM) concentrations, litterfall Hg depositions, and pool sizes in four adjacent stands at Mount Dongling to assess Hg dynamics in the forested catchment and the potential of Hg release during wildfires. The average GEM concentration was 2.5 ± 0.5 ng m-3, about 1.5 times of the background levels in the Northern Hemisphere. In all four stands, Hg concentrations increase in the following order: bole wood mineral soil litter < Oe soil < Oa organic soil. The Hg pools of aboveground biomass were comparable in the forests of larch, oak, and Chinese pine, which were much greater than that of mixed broadleaf stands due to lower biomass. The total Hg pools in ecosystems were similar in the four stands, because of the comparable Hg pool in the soil horizons (0-40 cm), which accounted for over 97% of the total ecosystem Hg storage in the four stands. Although Hg pools of the forest ecosystem in north China were comparable to North America and North Europe, Hg storage in forests constituted a high threat for large Hg emission pulses to the atmosphere by wildfires. The potential Hg emissions from the combustion at the four stands were ranged from 0.675 to 1.696 mg m-2.

  17. 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.

  18. Evaluating Ammonia Deposition Rates for Deciduous Forest using Measurements and Modelling

    DEFF Research Database (Denmark)

    Hansen, Kristina; Geels, Camilla; Hertel, Ole

    ). However, there are relatively few datasets of atmospheric NH3 fluxes available for forests which can contribute verifying model results. The atmospheric dry deposition of NH3 for the beech (Fagus sylvatica) forest, Lille Bøgeskov, in Sorø, Denmark, is investigated using the high resolution...... these impacts, quantifying the magnitude of the NH3 flux in the biosphere atmosphere system is essential. Model simulations using the Danish Ammonia Modelling System (DAMOS) have recently indicated that particular forest ecosystems are exposed to critical load exceedances of N (Geels et al., not yet submitted......-agricultural areas (Skjøth et al. 2011, ACPD). New atmospheric NH3 flux measurements for Lille Bøgeskov have been conducted throughout 2011 and these data are presented and discussed in relation to the 2010 data of atmospheric NH3. Future studies aim to improve the description of dry deposition of NH3 for vegetative...

  19. 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

  20. Driving factors behind the eutrophication signal in understorey plant communities of deciduous temperate forests

    Czech Academy of Sciences Publication Activity Database

    Verheyen, E.; Baeten, L.; De Frenne, P.; Brnhardt-Römermann, M.; Brunet, J.; Cornelis, J.; Decocq, G.; Dierschke, H.; Eriksson, O.; Hédl, Radim; Heinken, T.; Hermy, M.; Hommel, P.; Kirby, K.; Naaf, T.; Peterken, G.; Petřík, Petr; Pfadenhauer, J.; Van Calster, H.; Walther, G.-R.; Wulf, M.; Verstraeten, G.

    2012-01-01

    Roč. 100, č. 2 (2012), s. 352-365 ISSN 0022-0477 R&D Projects: GA AV ČR IAA600050812 Institutional research plan: CEZ:AV0Z60050516 Keywords : Ellenberg indicator values * forest management * large herbivores Subject RIV: EF - Botanics Impact factor: 5.431, year: 2012

  1. Aboveground and belowground mammalian herbivores regulate the demography of deciduous woody species in conifer forests

    Science.gov (United States)

    Bryan A. Endress; Bridgett J. Naylor; Burak K. Pekin; Michael J. Wisdom

    2016-01-01

    Mammalian herbivory can have profound impacts on plant population and community dynamics. However, our understanding of specific herbivore effects remains limited, even in regions with high densities of domestic and wild herbivores, such as the semiarid conifer forests of western North America. We conducted a seven-year manipulative experiment to evaluate the effects...

  2. Drought during canopy development has lasting effect on annual carbon balance in a deciduous temperate forest

    Science.gov (United States)

    Asko Noormets; Steve G. McNulty; Jared L. DeForest; Ge Sun; Qinglin Li; Jiquan Chen

    2008-01-01

    Climate change projections predict an intensifying hydrologic cycle and an increasing frequency of droughts, yet quantitative understanding of the effects on ecosystem carbon exchange remains limitedHere, the effect of contrasting precipitation and soil moisture dynamics were evaluated on forest carbon exchange using 2 yr of...

  3. Nutrient cycling in Huntington Forest and Turkey Lakes deciduous stands: Nitrogen and sulfur

    Energy Technology Data Exchange (ETDEWEB)

    Mitchell, M J [State Univ. of New York, Syracuse, NY (USA); Foster, N W; Morrison, I K [Forestry Canada, Sault Ste. Marie, ON (Canada); Shepard, J P [National Council of the Paper Industry for Air and Stream Improvement, Gainsville, FL (USA)

    1992-01-01

    A study was conducted to analyze two tolerant hardwood forests that are exhibiting different levels of nitrate and sulfate leaching. Fluxes of N and S at the two sites were compared, and the fluxes of nitrate and sulfate through the forest canopy, forest floor, and mineral soil were determined in order to ascertain whether differences in these fluxes could be explained using information on the N, S, and C biogeochemistry of each site. One site is in the Adirondack region, where the impacts of acidic deposition have been noted; the other site is in central Ontario, and has geological, pedological, and hydrological characteristics that make it potentially sensitive to acidic deposition. An increase in concentration of sulfate and nitrate was noted after passage through the canopy at both sites. The Ontario site showed much greater leaching of nitrate. At the Adirondack site only, there was a marked increase in sulfate flux when water leached from the forest floor through the soil. The mineral soil was the largest pool of N and S for both sites. The Ontario soil had a C/N ratio of 16:1, narrower than the 34:1 ratio of the soil at the other site. The former ratio should favor accumulation of ammonium and nitrate ions, and subsequent nitrate leaching. Laboratory measurements suggest that the forest floor at the Ontario site may have higher N mineralization rates. Fluxes of N and S within the vegetation were generally similar at both sites. The higher nitrate leaching at the Ontario site may be attributed mostly to stand maturity coupled with tree mortality, but the absence of slow decomposing beech leaf litter and lower C/N ratio in the soil may also be contributing factors. 50 refs., 3 figs., 6 tabs.

  4. Fire and the production of Astraeus odoratus (Basidiomycetes sporocarps in deciduous dipterocarp-oak forests of northern Thailand

    Directory of Open Access Journals (Sweden)

    Keegan H. Kennedy

    2012-12-01

    Full Text Available The genus Astraeus (Diplocystidiaceae forms ectomycorrhizal associations with many tree species and is a common gasteromycete in tropical and temperate ecosystems worldwide. In Thailand, Astraeus is most prevalent in deciduous dipterocarp-oak forest (DOF in the north and north-east and its ecology is uniquely associated with fire. Rural villagers often burn the seasonally dry DOF ground vegetation causing significant environmental disturbance to promote the growth of Astraeus sporocraps—a local culinary delicacy and important source of household income. The purpose of this work is to investigate whether the practice of burning DOF stimulates the production of Astraeus sporocarps in DOF. Burned and unburned Astraeus habitat was surveyed over two years at two sites in Chiang Mai province and one site in Mae Hong Son province. Changes in soil fungi after a fire as well as vascular vegetation growing with Astraeus were studied. All sporocarps collected were identified as Astraeus odoratus. Astraeus sporocarps were found in both burned and unburned areas in 2010. In 2011, an unusually wet year, no sporocarps were found in burned or unburned areas. The top 2 cm of soil experienced high temperatures which killed fungi, but lower depths were well insulated from the heat. A wide range of vascular flora grew in Astraeus habitat, the most common tree species being Dipterocarpus tuberculatus var. tuberculatus and Dipterocarpus obtusifolius var. obtusifolius. This study shows that Astraeus can produce sporocarps without fire and future work can focus on more environmentally benign methods of harvesting this popular mushroom.

  5. Leaf litter and roots as sources of mineral soil organic matter in temperate deciduous forest with and without earthworms

    Science.gov (United States)

    Fahey, T.; Yavitt, J. B.

    2012-12-01

    We labeled sugar maple trees with 13C to quantify the separate contributions of decaying leaf litter and root turnover/rhizosphere C flux to mineral soil organic matter (SOM). Labeled leaf litter was applied to forest plots with and without earthworms and recovery of the label in SOM was quantified over three years. In parallel, label recovery was quantified in soils from the labeling chambers where all label was supplied by belowground C flux. In the absence of earthworms about half of the label added as leaf litter remained in the surface organic horizons after three years, with about 3% recovered in mineral SOM. The label was most enriched on silt + clay surfaces, representing precipitation of DOC derived from litter. Earthworms mixed nearly all the leaf litter into mineral soil within one year, and after two years the label was most enriched in particulate organic matter held within soil aggregates produced by worms. After three years 15-20% of the added label was recovered in mineral SOM. In the labeling chambers over 75% of belowground C allocation (BCA) was used in root and rhizosphere respiration in the first year after labeling. We recovered only 3.8% of estimated BCA in SOM after 3 years; however, expressed as a proportion of fine root production plus rhizosphere C flux, this value is 15.4%, comparable to that for leaf litter in the presence of earthworms. In conclusion, both roots and leaf litter contribute significantly to the formation of stabilized mineral SOM in temperate deciduous forests, and this process is profoundly altered by the invasion of lumbricid earthworms.

  6. CHANGES IN SOIL MACROFAUNA IN AGROECOSYSTEMS DERIVED FROM LOW DECIDUOUS TROPICAL FOREST ON LEPTOSOLS FROM KARSTIC ZONES

    Directory of Open Access Journals (Sweden)

    Francisco Bautista

    2009-02-01

    Full Text Available In Yucatan Mexico the method of slash and burn is used for the establishment of pastures. Pastures are developed for 15 to 20 years, no more because weed control is too expensive. The impact of these practices on soil macrofauna had not been evaluated. Because of its wide distribution, diverse habits and high sensitivity to disturbance, soil macrofauna is considered a valuable indicator of soil health, allowing monitoring of soil sustainability. We studied soil macrofauna communities in low deciduous tropical forest and four livestock agroecosystems with increasing management-derived disturbance including a silvopastoral system, Taiwan grass (Cynodon nlemfuensis and Star grass (Pennisetum purpureum pastures in order to describe community structure across systems, and evaluate disturbance sensitivity of taxonomical groups to detect taxa with potential use as biological indicators of soil health or degradation. Pitfall traps were used at each of the systems to sample soil macrofauna. We estimate their taxonomical abundance, biomass, richness (order, morphospecies, diversity, dominance and response to disturbance on agroecosystems and the forest. We found 133 macrofauna morphospecies of 15 taxa. Groups with more individuals were: Hymenoptera (64.97%, Coleoptera (22.68%, and Orthoptera (3.91%.  Agroecosystem of two-year old Taiwan-grass pasture (TP2 had the highest macrofauna abundances, biomass and richness, low diversity, and a non-homogeneous distribution of individuals among species; in contrast, silvopastoral system (SP, had low abundance and biomass, the lowest specific richness, high diversity and a homogeneous distribution of individuals among species. The discriminant analysis revealed that the agroecosystems and the forest serve to predict the macrofauna communities, since they have particular or typical soil macrofauna. The cases (sampled points with a correct assignation by agroecosystems were: Forest (70%, Sivopastoral system (70

  7. Background concentrations and fluxes of atmospheric ammonia over a deciduous forest

    DEFF Research Database (Denmark)

    Hansen, K.; Pryor, S. C.; Boegh, E.

    2015-01-01

    . In this study, we present two months of half-hourly NH3 fluxes and concentrations measured using a Relaxed Eddy Accumulation system during late summer and fall 2013 above a remote forest site in the central Midwest in USA. Supplementary nitric acid (HNO3) flux and size-resolved aerosol-N measurements are used.......11 μg NH3-N m−2 s−1. The wetness of the forest surfaces (assessed using a proxy of time since precipitation) was found to be crucial in controlling both deposition and emission of atmospheric NH3. Size resolved aerosol concentrations (of NH4+, NO3−, Cl− and SO42−) indicated that the aerosol and gas...

  8. 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

  9. 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

  10. Are Boreal Ovenbirds, Seiurus aurocapilla, More Prone to Move across Inhospitable Landscapes in Alberta's Boreal Mixedwood Forest than in Southern Québec's Temperate Deciduous Forest?

    Directory of Open Access Journals (Sweden)

    Marc Bélisle

    2007-12-01

    Full Text Available Population life-history traits such as the propensity to move across inhospitable landscapes should be shaped by exposure to landscape structure over evolutionary time. Thus, birds that recently evolved in landscapes fragmented by natural disturbances such as fire would be expected to show greater behavioral and morphological vagility relative to conspecifics that evolved under less patchy landscapes shaped by fewer and finer-scaled disturbances, i.e., the resilience hypothesis. These predictions are not new, but they remain largely untested, even for well-studied taxa such as neotropical migrant birds. We combined two experimental translocation, i.e., homing, studies to test whether Ovenbird, Seiurus aurocapilla, from the historically dynamic boreal mixedwood forest of north-central Alberta (n = 55 is more vagile than Ovenbird from historically less dynamic deciduous forest of southern Québec (n = 89. We found no regional difference in either wing loading or the response of homing Ovenbird to landscape structure. Nevertheless, this study presents a heuristic framework that can advance the understanding of boreal landscape dynamics as an evolutionary force.

  11. 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.

  12. Eastern deciduous forest biome progress report, September 1, 1975--August 31, 1976

    International Nuclear Information System (INIS)

    Burgess, R.L.; Tarr, N.E.

    1978-09-01

    The report concentrates on the six projects as well as results from synthesis activities at the Lake George, Lake Wingra, and Oak Ridge sites. The centralized analysis and modeling component and the Eastern Decidious Forest Biome Information Center progress during the past year are also addressed. The project on belowground dynamics of ecosystems is investigating the allocation of phytosynthetic products into fixed or labile storage pools. Root sampling, radioactive tracer techniques, and biochemical analyses are leading to an understanding of complete tree physioogy requisite for interpreting forest growth in different environments. The Role of Consumers project has begun to document the regulatory role of heterotrophs in an array of ecosystem niches. Decomposition of woody substrates, studies of the contribution of canopy and litter arthropods to material processing, and the flow and remineralization of phosphorus in lake systems are leading to a comprehensive understanding of the role of consumer organisms in ecosystem function. The Microdynamics of Detritus project continues its investigations of carbon and nitrogen dynamics in freshwater lakes. Examination of potential pathways of detritus processing is illustrating the parts that physical and biological processes play in the breakdown of organic materials

  13. Environmental fate and distribution of technetium-99 in a deciduous forest ecosystem

    International Nuclear Information System (INIS)

    Garten, C.T. Jr.; Tucker, C.S.; Walton, B.T.

    1986-01-01

    The uptake of 99 Tc by trees intercepting contaminated groundwater from a radioactive waste storage site was measured to identify the major 99 Tc pools within the woodland ecosystem and to assess the relative mobility of 99 Tc in the existing element cycle. The highest average 99 Tc concentrations in vegetation were found in herbaceous plants. Tree wood was the major above-ground pool for 99 Tc because of the high concentrations in wood as well as the large amount of wood relative to other biomass at the site. Technetium was not easily leached from the trees by rainfall and was not readily extractable from forest floor leaf litter by water. The relative importance of return pathways for 99 Tc to the forest floor was leaf fall > stemflow > throughfall, indicating that 99 Tc was conserved by the trees. Snails and millipedes from the leaf litter layer concentrated technetium 20- and 16-fold, respectively, above levels found in the soil. Pertechnetate was rendered less bioavailable after ingestion by a leaf litter macroinvertebrate (Porcellio sp.) common to the study site. (author)

  14. Temporal changes in radiocesium deposition in various forest stands following the Fukushima Dai-ichi Nuclear Power Plant accident.

    Science.gov (United States)

    Kato, Hiroaki; Onda, Yuichi; Hisadome, Keigo; Loffredo, Nicolas; Kawamori, Ayumi

    2017-01-01

    In this study, we investigated the transfer of canopy-intercepted radiocesium to the forest floor following the Fukushima Dai-ichi Nuclear Power Plant accident. The 137 Cs content of throughfall, stemflow, and litterfall were monitored in two coniferous stands (plantations of Japanese cedar) and a deciduous mixed broad-leaved forest stand (oak with red pine) from July 2011 to December 2012. The forest floor of cedar stands had received higher levels of additional 137 Cs deposition compared with the mixed broad-leaved stand during the sampling period. The cumulative 137 Cs deposition during the study period was 119 kBq m -2 for the mature cedar stand, 105 kBq m -2 for the young cedar stand, and 41.5 kBq m -2 for the broad-leaved stand. The deposition of 137 Cs to the forest floor occurred mainly in throughfall during the first rainy season, from July to September 2011 (<200 d after the initial fallout); thereafter, the transfer of 137 Cs from the canopy to forest floor occurred mainly through litterfall. A double exponential field-loss model, which was used to simulate the removal of 137 Cs from canopies, was the best fit for the temporal changes in the canopy 137 Cs inventory. Copyright © 2015 Elsevier Ltd. All rights reserved.

  15. Assessment of species diversity of plants and carabid beetles at sample plots in Korean pine-broad-leaved stands of postfire origin

    Directory of Open Access Journals (Sweden)

    A. V. Ivanov

    2018-06-01

    Full Text Available For natural pine forests in the southern part of the Primorsky Krai, an assessment of biological diversity has been performed based on the results of descriptions of valuable tree species, living ground cover and carabid beetles Carabus. Field work was carried out on the trial plots laid in the forest plantations of the pine and broad-leaved forest with the domination of Korean pine Pinus koraiensis Siebold & Zucc. Model sites contained a chronological sequence of development of forest plantations of fresh small-grass and different-bush type on the interval of age 50–200 years. In the process of reforestation, a decrease in the total projective coverage of living ground cover was observed, while the number of species characteristic for natural pine forests, as well as their leveling, increased at the same time. By the age of 200 years species richness and leveling of the number of ground beetle species have reached a maximum. Statistically significant difference was found between the total number of caught insects in the plantations of 50 and 200, 80 and 200 years. The most valuable in terms of biological diversity are the old-growth pine forests. A conclusion was made about the value of this group of forests for the protection of valuable communities and habitats of species. Among ground beetle species Carabus schrencki Motschulsky, Carabus maacki Morawitz and Carabus macleayi Dejean can serve as an indicator of forest value. With a minimum total projective coverage (8.3 %, 200-year-old pine forests are favorable for the growth of such characteristic species as the mountain peony Paeonia oreogeton S. Moore, pale-mountain Dryopteris crassirhizoma Nakai, and the Pale Indian Plantain Cacalia auriculata H. Rob. & Brettell. On this site the Shannon index of species of living ground cover was 3.6, the Carabus species is 1.4.

  16. 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

  17. Endocarp thickness affects seed removal speed by small rodents in a warm-temperate broad-leafed deciduous forest, China

    Science.gov (United States)

    Zhang, Hongmao; Zhang, Zhibin

    2008-11-01

    Seed traits are important factors affecting seed predation by rodents and thereby the success of recruitment. Seeds of many tree species have hard hulls. These are thought to confer mechanical protection, but the effect of endocarp thickness on seed predation by rodents has not been well investigated. Wild apricot ( Prunus armeniaca), wild peach ( Amygdalus davidiana), cultivated walnut ( Juglans regia), wild walnut ( Juglans mandshurica Maxim) and Liaodong oak ( Quercus liaotungensis) are very common tree species in northwestern Beijing city, China. Their seeds vary greatly in size, endocarp thickness, caloric value and tannin content. This paper aims to study the effects of seed traits on seed removal speed of these five tree species by small rodents in a temperate deciduous forest, with emphasis on the effect of endocarp thickness. The results indicated that speed of removal of seeds released at stations in the field decreased significantly with increasing endocarp thickness. We found no significant correlations between seed removal speed and other seed traits such as seed size, caloric value and tannin content. In seed selection experiments in small cages, Père David's rock squirrel ( Sciurotamias davidianus), a large-bodied, strong-jawed rodent, selected all of the five seed species, and the selection order among the five seed species was determined by endocarp thickness and the ratio of endocarp mass/seed mass. In contrast, the Korean field mouse ( Apodemus peninsulae) and Chinese white-bellied rat ( Niviventer confucianus), with relatively small bodies and weak jaws, preferred to select small seeds like acorns of Q. liaotungensis and seeds of P. armeniaca, indicating that rodent body size is also an important factor affecting food selection based on seed size. These results suggest endocarp thickness significantly reduces seed removal speed by rodents and then negatively affects dispersal fitness of seeds before seed removal of tree species in the study

  18. Antioxidant content in two CAM bromeliad species as a response to seasonal light changes in a tropical dry deciduous forest.

    Science.gov (United States)

    González-Salvatierra, Claudia; Luis Andrade, José; Escalante-Erosa, Fabiola; García-Sosa, Karlina; Manuel Peña-Rodríguez, Luis

    2010-07-01

    Plants have evolved photoprotective mechanisms to limit photodamage; one of these mechanisms involves the biosynthesis of antioxidant metabolites to neutralize reactive oxygen species generated when plants are exposed to excess light. However, it is known that exposure of plants to conditions of extreme water stress and high light intensity results in their enhanced susceptibility to over-excitation of photosystem II and to photooxidative stress. In this investigation we used the 2,2-diphenyl-1-picrylhydrazyl reduction assay to conduct a broad survey of the effect of water availability and light exposure conditions on the antioxidant activity of the leaf extracts of two bromeliad species showing crassulacean acid metabolism. One of these was an epiphyte, Tillandsia brachycaulos, and the other a terrestrial species, Bromelia karatas. Both species were found growing wild in the tropical dry deciduous forest of Dzibilchaltún National Park, México. The microenvironment of T. brachycaulos and B. karatas experiences significant diurnal and seasonal light variations as well as changes in temperature and water availability. The results obtained showed that, for both bromeliads, increases in antioxidant activity occurred during the dry season, as a consequence of water stress and higher light conditions. Additionally, in T. brachycaulos there was a clear correlation between high light intensity conditions and the content of anthocyanins which accumulated below the leaf epidermis. This result suggests that the role of these pigments is as photoprotective screens in the leaves. The red coloration below the leaf epidermis of B. karatas was not due to anthocyanins but to other unidentified pigments. 2010 Elsevier GmbH. All rights reserved.

  19. Effects of drought on leaf gas exchange in an eastern broadleaf deciduous forest

    Science.gov (United States)

    Roman, D. T.; Brzostek, E. R.; Dragoni, D.; Rahman, A. F.; Novick, K. A.; Phillips, R.

    2013-12-01

    Understanding plant physiological adaptations to drought is critical for predicting changes in ecosystem productivity that result from climate variability and future climate change. From 2011-2013, southern Indiana experienced a late growing season drought in 2011, a severe early season drought in 2012, and a wet growing season in 2013 characterized by an absence of water stress with frequent precipitation and milder temperatures. The 2012 drought was unique due to the severity and early onset drought conditions (compared to the more frequent late season drought) and was characterized by a Palmer Drought severity index below -4 and precipitation totals from May - July that were 70% less than the long-term (2000 - 2010) mean. During the 2012 drought, an 11% decline in net ecosystem productivity relative to the long-term mean was observed at the AmeriFlux tower in Morgan Monroe State Forest despite a growing season that started ~25 days earlier. Thus, the objective of this study is to evaluate species-specific contributions to the canopy-scale response to inter-annual variability in water stress. We investigated differences between tree species in their response to climate variability using weekly leaf gas exchange and leaf water potential measurements during the growing seasons of 2011-2013. We used this unique dataset, collected at the top of the canopy with a 25 m boom lift, to evaluate changes in leaf water status and maximum assimilation capacity in the drought versus non-drought years. The leaf-level physiology of oak (Quercus) species appears to be less sensitive to drought than other species (tulip poplar [Liriodendron tulipifera], sassafras [Sassafras albidum] and sugar maple [Acer saccharum]). Preliminary data shows mean canopy leaf water potential for oaks was 30.5% more negative in May-July 2012 versus the same time period in 2013. During these same periods the rate of C assimilation in oaks was reduced by only 3%, whereas other species were reduced by

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

    Science.gov (United States)

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

    2017-06-01

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

  1. A metagenomics-based approach to the top-down effect on the detritivore food web: a salamanders influence on fungal communities within a deciduous forest.

    Science.gov (United States)

    Walker, Donald M; Lawrence, Brandy R; Esterline, Dakota; Graham, Sean P; Edelbrock, Michael A; Wooten, Jessica A

    2014-11-01

    The flow of energy within an ecosystem can be considered either top-down, where predators influence consumers, or bottom-up, where producers influence consumers. Plethodon cinereus (Red-backed Salamander) is a terrestrial keystone predator who feeds on invertebrates within the ecosystem. We investigated the impact of the removal of P. cinereus on the detritivore food web in an upland deciduous forest in northwest Ohio, U.S.A. A total of eight aluminum enclosures, each containing a single P. cinereus under a small log, were constructed in the deciduous forest. On Day 1 of the experiment, four salamanders were evicted from four of the eight enclosures. Organic matter and soil were collected from the center of each enclosure at Day 1 and Day 21. From each sample, DNA was extracted, fungal-specific amplification performed, and 454 pyrosequencing was used to sequence the nuclear ribosomal internal transcribed spacer (ITS2) region and partial ribosomal large subunit (LSU). Changes in overall fungal community composition or species diversity were not statistically significant between treatments. Statistically significant shifts in the most abundant taxonomic groups of fungi were documented in presence but not absence enclosures. We concluded that P. cinereus does not affect the overall composition or diversity of fungal communities, but does have an impact on specific groups of fungi. This study used a metagenomics-based approach to investigate a missing link among a keystone predator, P. cinereus, invertebrates, and fungal communities, all of which are critical in the detritivore food web.

  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. Forest vegetation of Xishuangbanna, south China

    Institute of Scientific and Technical Information of China (English)

    Zhu Hua

    2006-01-01

    Xishuangbanna of southern Yunnan is biogeographically located at a transitional zone from tropical southeast (SE) Asia to subtropical east Asia and is at the junction of the Indian and Burmese plates of Gondwana and the Eurasian plate of Laurasia. The region, though surprisingly far from the equator and at a relatively high altitude, has a rich tropical flora and a typical tropical rain forest in the lowland areas. Based on physiognomic and ecological characteristics, floristic composition and habitats combined, the primary vegetation in Xishuangbanna can be organized into four main vegetation types: tropical rain forest, tropical seasonal moist forest, tropical montane evergreen broad-leaved forest and tropical monsoon forest. The tropical rain forest can be classified into two subtypes, i.e. a tropical seasonal rain forest in the lowlands and a tropical montane rain forest at higher elevations. The tropical seasonal rain forest has almost the same forest profile and physiognomic characteristics as equatorial lowland rain forests and is a type of truly tropical rain forest. Because of conspicuous similarity on ecological and floristic characteristics, the tropical rain forest in Xishuangbanna is a type of tropical Asian rain forest. However, since the tropical rain forest of Xishuangbanna occurs at the northern edge of tropical SE Asia, it differs from typical lowland rain forests in equatorial areas in having some deciduous trees in the canopy layer, fewer megaphanerophytes and epiphytes but more abundant lianas and more plants with microphyll. It is a type of semi-evergreen rain forest at the northern edge of the tropical zone. The tropical montane rain forest occurs at wet montane habitats and is similar to the lower montane rain forest in equatorial Asia in floristic composition and physiognomy. It is a type of lower montane rain forests within the broader category of tropical rain forests. The tropical seasonal moist forest occurs on middle and upper

  5. 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...

  6. The leaf size-twig size spectrum in evergreen broadleaved forest of ...

    African Journals Online (AJOL)

    Compared to deciduous broad-leaved species, the evergreen broad-leaved species were smaller in total leaf area for a given cross-sectional area or stem mass. This suggests that the species would support less leaf area at a given twig cross-sectional area with increasing environmental stress. And the life form can modify ...

  7. Elevated native terrestrial snail abundance and diversity in association with an invasive understory shrub, Berberis thunbergii, in a North American deciduous forest

    Science.gov (United States)

    Utz, Ryan M.; Pearce, Timothy A.; Lewis, Danielle L.; Mannino, Joseph C.

    2018-01-01

    Invasive terrestrial plants often substantially reshape environments, yet how such invasions affect terrestrial snail assemblages remains understudied. We investigated how snail assemblages in deciduous forest soils with dense Berberis thunbergii (Japanese barberry), an invasive shrub in eastern North America, differ from forest areas lacking the shrub. Leaf litter and soil samples were collected from forest patches with dense B. thunbergii understories and adjacent control areas within two exurban forest tracts in western Pennsylvania, U.S.A. Snails were identified to species and quantified by standard diversity metrics. Contrary to our expectations, snails were significantly more abundant and diverse in B. thunbergii-invaded areas. Despite differences in abundance, the snail community composition did not differ between invaded and control habitats. The terrestrial snail assemblage we observed, which was composed entirely of native species, appears to respond favorably to B. thunbergii invasion and therefore may not be negatively impacted by physicochemical changes to soils typically observed in association with the plant. Such findings could reflect the fact that B. thunbergii likely creates more favorable habitat for snails by creating cooler, more humid, and more alkaline soil environments. However, the snail assemblages we retrieved may consist mostly of species with high tolerance to environmental degradation due to a legacy of land use change and acid deposition in the region.

  8. Florística e estrutura da comunidade arbórea de um remanescente de Floresta Estacional Decidual de encosta, Monte Alegre, GO, Brasil Floristic and structure of a seasonal deciduous forest fragment, Monte Alegre, GO, Brazil

    Directory of Open Access Journals (Sweden)

    André R. Terra Nascimento

    2004-09-01

    Full Text Available O presente estudo teve como objetivo descrever a composição de espécies arbóreas e a estrutura de um fragmento de Floresta Estacional Decidual, na região Nordeste de Goiás, Brasil. Foram levantadas 25 unidades amostrais quadradas de 20x20m, totalizando uma amostra de um hectare, sendo incluídos na amostragem todos os indivíduos com diâmetros iguais ou superiores a 5cm. Foram amostrados 663 indivíduos pertencentes a 52 espécies arbóreas, destacando-se pela densidade as espécies Combretum duarteanum Camb., Casearia rupestris Eichl., Myracrodruon urundeuva Fr. Allem., Machaerium acutifolium Vog. e Tabebuia impetiginosa (Mart. ex DC. Standl. Foram encontradas 21 famílias botânicas, com maior representatividade da família Leguminosae (17 espécies e das famílias Bignoniaceae (4 espécies, Anacardiaceae (3 espécies e Bombacaceae (3 espécies. A vegetação estudada apresentou dossel descontínuo e distribuição diamétrica desequilibrada, com valores do quociente de Liocourt "q" variando de q1= 0,66 a q6 = 0,14. Estes remanescentes florestais desempenham papel importante na manutenção da diversidade biológica e possuem espécies arbóreas madeiráveis de importância econômica, que se tornaram raras em outros locais da região Nordeste de Goiás.The objective of this study was to describe the floristic composition and the structure of the tree layer of a fragment of a seasonal deciduous forest in northeastern Goiás state, Brazil. A sample of 25 (20x20 plots was assessed totaling one hectare. All individuals for 5cm dbh were included in the survey. A total of 663 trees in 52 arboreal species was found; the most abundant species were Combretum duarteanum Camb., Casearia rupestris Eichl., Myracrodruon urundeuva Fr. Allem., Machaerium acutifolium Vog. and Tabebuia impetiginosa (Mart. ex DC. Standl. There were 21 families with a higher proportion of Leguminosae (17 species Bignoniaceae (4 species, Anacardiaceae (3 species and

  9. Mapping forest functional type in a forest-shrubland ecotone using SPOT imagery and predictive habitat distribution modelling

    Science.gov (United States)

    Assal, Timothy J.; Anderson, Patrick J.; Sibold, Jason

    2015-01-01

    The availability of land cover data at local scales is an important component in forest management and monitoring efforts. Regional land cover data seldom provide detailed information needed to support local management needs. Here we present a transferable framework to model forest cover by major plant functional type using aerial photos, multi-date Système Pour l’Observation de la Terre (SPOT) imagery, and topographic variables. We developed probability of occurrence models for deciduous broad-leaved forest and needle-leaved evergreen forest using logistic regression in the southern portion of the Wyoming Basin Ecoregion. The model outputs were combined into a synthesis map depicting deciduous and coniferous forest cover type. We evaluated the models and synthesis map using a field-validated, independent data source. Results showed strong relationships between forest cover and model variables, and the synthesis map was accurate with an overall correct classification rate of 0.87 and Cohen’s kappa value of 0.81. The results suggest our method adequately captures the functional type, size, and distribution pattern of forest cover in a spatially heterogeneous landscape.

  10. Soil organic matter composition and quality across fire severity gradients in coniferous and deciduous forests of the southern boreal region

    Science.gov (United States)

    Jessica R. Miesel; William C. Hockaday; Randy Kolka; Philip A. Townsend

    2015-01-01

    Recent patterns of prolonged regional drought in southern boreal forests of the Great Lakes region, USA, suggest that the ecological effects of disturbance by wildfire may become increasingly severe. Losses of forest soil organic matter (SOM) during fire can limit soil nutrient availability and forest regeneration. These processes are also influenced by the composition...

  11. 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.

  12. 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.

  13. 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.

  14. 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

  15. Dynamics of a temperate deciduous forest under landscape-scale management: Implications for adaptability to climate change

    Science.gov (United States)

    Matthew G. Olson; Benjamin O. Knapp; John M. Kabrick

    2017-01-01

    Landscape forest management is an approach to meeting diverse objectives that collectively span multiple spatial scales. It is critical that we understand the long-term effects of landscape management on the structure and composition of forest tree communities to ensure that these practices are sustainable. Furthermore, it is increasingly important to also consider...

  16. Use of the isotope flux ratio approach to investigate the C18O16O and 13CO2 exchange near the floor of a temperate deciduous forest

    Directory of Open Access Journals (Sweden)

    P. Bartlett

    2012-07-01

    Full Text Available Stable isotopologues of CO2, such as 13CO2 and C18OO, have been used to study the CO2 exchange between land and atmosphere. The advent of new measuring techniques has allowed near-continuous measurements of stable isotopes in the air. These measurements can be used with micrometeorological techniques, providing new tools to investigate the isotope exchange in ecosystems. The objectives of this study were to evaluate the use of the isotope flux ratio method (IFR near the forest floor of a temperate deciduous forest and to study the temporal dynamics of δ18O of CO2 flux near the forest floor by comparing IFR estimates with estimates of δ18O of net soil CO2 flux provided by an analytical model. Mixing ratios of 12C16O2, 13CO2 and C16O18O were measured within and above a temperate deciduous forest, using the tunable diode laser spectroscopy technique. The half-hourly compositions of the CO2 flux near the forest floor (δ13CF and δ18OF were calculated by IFR and compared with estimates provided by a modified Keeling plot technique (mKP and by a Lagrangian dispersion analysis (WT analysis. The mKP and IFR δ18OF estimates showed good agreement (slope = 1.03 and correlation, R2 = 0.80. The δ13CF estimates from the two methods varied in a narrow range of −32.7 and −23‰; the mean (± SE mKP and IFR δ13CF values were −27.5‰ (±0.2 and −27.3‰ (±0.1, respectively, and were statistically identical (p>0.05. WT analysis and IFR δ18OF estimates showed better correlation (R2 = 0.37 when only turbulent periods (u*>0.6 m s−1 were included in the analysis. The large amount of data captured (~95 % of half-hour periods evaluated for the IFR in comparison with mKP (27 % shows that the former provides new opportunities for studying δ18OF dynamics within forest canopies. Values of δ18OF showed large temporal variation, with values ranging from −31.4‰ (DOY 208 to −11.2‰ (DOY 221. Precipitation events caused substantial variation (~8

  17. Influence of moisture conditions and mineralization of soil solution on structure of litter macrofauna of the deciduous forests of Ukraine steppe zone

    Directory of Open Access Journals (Sweden)

    V. V. Brygadyrenko

    2015-02-01

    Full Text Available The accounting of litter mesofauna was carried out in the territory of Dnipropetrovsk, Zaporizhzhya, Nikolaev,Donetsk regions of Ukrainein the natural forest ecosystems in 2001–2014. 339 forest ecosystems were surveyed; xeromesophilic conditions of moistening were characteristic for 47 trial sites, mesophilic conditions – for 99 sites, hygro-mesophilic conditions – for 50 sites, meso-hygrophilic conditions – for 89 sites, hygrophilic conditions – for 54 sites; trophotope C was represented by 35 trial sites, Dc – by 44, Dac – by 76, Dn – by 128, De – by 37, E – by 19 forest ecosystems, accordingly. The relative number of saprophages reaches maximum values in hygro-mesophilic, meso-hygrophilic and hygrophilic conditions, and minimum values – in mesophilic conditions of moistening. The share of rare species is maximum in hygro-mesophilic conditions of moistening. The minimum quantity of mass species is also observed in conditions of hygro-mesophilic and meso-hygrophilic deciduous forests. With the growth of moistening of the soil, quantity of species of Carabidae, Formicidae and other dominant families remains without significant changes. The relative number of Formicidae is maximum in xeromesophilic and mesophilic conditions of soil moistening. In these hygrotopes, as well as in hygro-mesophilic conditions of moistening the Julidae numbers are maximum. The Isopoda percent in mesofauna significantly grows in meso-hygrophilic and hygrophilic conditions of moistening. The share of other dominant taxonomical groups in the structure of litter mesofauna remains without significant changes in numbers. In the majority of the analysed hygrotopes 7–8 families are withing the structure of dominants. In the conditions of salinization (trophotopes De and E, and also on light sandy loam soils, the numbers of litter mesofauna decrease. Share of saprophages is minimum in trophotopes Dc and E, while it increases in trophotopes C, Dac, Dn

  18. The Effects of Exurbanization on Bird and Macro invertebrate Communities in Deciduous Forests on the Cumberland Plateau, Tennessee

    International Nuclear Information System (INIS)

    Casey, J.M.; Wilson, M.E.; Haskell, D.G.; Hollingshead, N.

    2009-01-01

    To investigate the potential causes of changes to bird communities in exurban areas, we examined the relationship between bird and macro invertebrate communities in exurbanized forest. We randomly located sampling points across a gradient of exurbanization. We used point counts to quantify bird communities and sweep netting, soil cores, pitfalls, and frass collectors to quantify macro invertebrates. Bird communities had higher richness and abundance in exurban areas compared to undeveloped forests, and lost some species of conservation concern but gained others. The macro invertebrate community was slightly more abundant in exurban areas, with a slight shift in taxonomic composition. The abundance of macro invertebrates in soil cores (but not pitfalls) predicted the abundance of ground-foraging birds. The abundance of macro invertebrates in sweep nets was not associated with the abundance of aerial insectivore birds. Exurbanization therefore appears to change bird and macro invertebrate communities, but to a lesser extent than agricultural forest fragmentation or intensive urbanization.

  19. The Effects of Exurbanization on Bird and Macroinvertebrate Communities in Deciduous Forests on the Cumberland Plateau, Tennessee

    Directory of Open Access Journals (Sweden)

    Jordan M. Casey

    2009-01-01

    Full Text Available To investigate the potential causes of changes to bird communities in exurban areas, we examined the relationship between bird and macroinvertebrate communities in exurbanized forest. We randomly located sampling points across a gradient of exurbanization. We used point counts to quantify bird communities and sweep netting, soil cores, pitfalls, and frass collectors to quantify macroinvertebrates. Bird communities had higher richness and abundance in exurban areas compared to undeveloped forests, and lost some species of conservation concern but gained others. The macroinvertebrate community was slightly more abundant in exurban areas, with a slight shift in taxonomic composition. The abundance of macroinvertebrates in soil cores (but not pitfalls predicted the abundance of ground-foraging birds. The abundance of macroinvertebrates in sweep nets was not associated with the abundance of aerial insectivore birds. Exurbanization therefore appears to change bird and macroinvertebrate communities, but to a lesser extent than agricultural forest fragmentation or intensive urbanization.

  20. Modelling the decadal trend of ecosystem carbon fluxes demonstrates the important role of functional changes in a temperate deciduous forest

    DEFF Research Database (Denmark)

    Wu, Jian; Jansson, P.E.; van der Linden, Leon

    2013-01-01

    Temperate forests are globally important carbon sinks and stocks. Trends in net ecosystem exchange have been observed in a Danish beech forest and this trend cannot be entirely attributed to changing climatic drivers. This study sought to clarify the mechanisms responsible for the observed trend...... for nitrogen demand during mast years is supported by the inter-annual variability in the estimated parameters. The inter-annual variability of photosynthesis parameters was fundamental to the simulation of the trend in carbon fluxes in the investigated beech forest and this demonstrates the importance......, the latent and sensible heat fluxes and the CO2 fluxes decreased the parameter uncertainty considerably compared to using CO2 fluxes as validation data alone. The fitted model was able to simulate the observed carbon fluxes well (R2=0.8, mean error=0.1gCm−2d−1) but did not reproduce the decadal (1997...

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

    Directory of Open Access Journals (Sweden)

    FH. Oda

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

  2. CHEMICAL COMPOSITION, IN VITRO RUMEN FERMENTATION, AND DIGESTIBILITY OF SELECTED BROWSE SPECIES BY BUFFALOES (Bubalus bubalis L. AT A SEMI-DECIDUOUS FOREST IN VENEZUELA

    Directory of Open Access Journals (Sweden)

    Álvaro José Ojeda

    2013-01-01

    Full Text Available To determine the chemical composition and nutritive value of selected browse species by buffaloes (Bubalus bubalis L. in a silvopastoral system at a semi-deciduous tropical forest (SDTF, epidermal fragments in fecal samples from 14 males of Murrah breed were evaluated. The animals grazed for 91 days in 85 ha located in Portuguesa State, Venezuela, of which 35 ha corresponded to natural grass pastures (969.3 ± 28.6 kg DM ha-1, and the rest to SDTF with 463 plant ha-1. Eleven botanical families and 22 species were identified, 40.9% belonged to the Fabaceae family. The specie Guazuma ulmifolia (Sterculiaceae had the highest relative dominancy (60.4% and an Importance Value Index of 162.6. 60.4% of epidermal fragments corresponded to herbaceous Poaceae, and the rest was distributed among five different species, with the highest occurrence (94.6% for Samanea saman and Sida acuta. There were differences (P

  3. Efficacy of Pitfall Trapping, Winkler and Berlese Extraction Methods for Measuring Ground-Dwelling Arthropods in Moist-Deciduous Forests in the Western Ghats

    Science.gov (United States)

    Sabu, Thomas K.; Shiju, Raj T.

    2010-01-01

    The present study provides data to decide on the most appropriate method for sampling of ground-dwelling arthropods measured in a moist-deciduous forest in the Western Ghats in South India. The abundance of ground-dwelling arthropods was compared among large numbers of samples obtained using pitfall trapping, Berlese and Winkler extraction methods. Highest abundance and frequency of most of the represented taxa indicated pitfall trapping as the ideal method for sampling of ground-dwelling arthropods. However, with possible bias towards surface-active taxa, pitfall-trapping data is inappropriate for quantitative studies, and Berlese extraction is the better alternative. Berlese extraction is the better method for quantitative measurements than the other two methods, whereas pitfall trapping would be appropriate for qualitative measurements. A comparison of the Berlese and Winkler extraction data shows that in a quantitative multigroup approach, Winkler extraction was inferior to Berlese extraction because the total number of arthropods caught was the lowest; and many of the taxa that were caught from an identical sample via Berlese extraction method were not caught. Significantly a greater frequency and higher abundance of arthropods belonging to Orthoptera, Blattaria, and Diptera occurred in pitfall-trapped samples and Psocoptera and Acariformes in Berlese-extracted samples than that were obtained in the other two methods, indicating that both methods are useful, one complementing the other, eliminating a chance for possible under-representation of taxa in quantitative studies. PMID:20673122

  4. The impact of growing-season length variability on carbon assimilation and evapotranspiration over 88 years in the eastern US deciduous forest

    Science.gov (United States)

    White; Running; Thornton

    1999-02-01

    Recent research suggests that increases in growing-season length (GSL) in mid-northern latitudes may be partially responsible for increased forest growth and carbon sequestration. We used the BIOME-BGC ecosystem model to investigate the impacts of including a dynamically regulated GSL on simulated carbon and water balance over a historical 88-year record (1900-1987) for 12 sites in the eastern USA deciduous broadleaf forest. For individual sites, the predicted GSL regularly varied by more than 15 days. When grouped into three climatic zones, GSL variability was still large and rapid. There is a recent trend in colder, northern sites toward a longer GSL, but not in moderate and warm climates. The results show that, for all sites, prediction of a long GSL versus using the mean GSL increased net ecosystem production (NEP), gross primary production (GPP), and evapotranspiration (ET); conversely a short GSL is predicted to decrease these parameters. On an absolute basis, differences in GPP between the dynamic and mean GSL simulations were larger than the differences in NEP. As a percentage difference, though, NEP was much more sensitive to changes in GSL than were either GPP or ET. On average, a 1-day change in GSL changed NEP by 1.6%, GPP by 0.5%, and ET by 0.2%. Predictions of NEP and GPP in cold climates were more sensitive to changes in GSL than were predictions in warm climates. ET was not similarly sensitive. First, our results strongly agree with field measurements showing a high correlation between NEP and dates of spring growth, and second they suggest that persistent increases in GSL may lead to long-term increases in carbon storage.

  5. Habitat properties are key drivers of Borrelia burgdorferi (s.l.) prevalence in Ixodes ricinus populations of deciduous forest fragments

    OpenAIRE

    Ehrmann, Steffen; Ruyts, Sanne C.; Scherer-Lorenzen, Michael; Bauhus, Jürgen; Brunet, Jörg; Cousins, Sara A. O.; Deconchat, Marc; Decocq, Guillaume; De Frenne, Pieter; De Smedt, Pallieter; Diekmann, Martin; Gallet-Moron, Emilie; Gärtner, Stefanie; Hansen, Karin; Kolb, Annette

    2018-01-01

    Background The tick Ixodes ricinus has considerable impact on the health of humans and other terrestrial animals because it transmits several tick-borne pathogens (TBPs) such as B. burgdorferi (sensu lato), which causes Lyme borreliosis (LB). Small forest patches of agricultural landscapes provide many ecosystem services and also the disservice of LB risk. Biotic interactions and environmental filtering shape tick host communities distinctively between specific regions of Europe, which makes ...

  6. Cycling of acid and base cations in deciduous stands of Huntington Forest, New York, and Turkey Lakes, Ontario

    Energy Technology Data Exchange (ETDEWEB)

    Foster, N W; Morrison, I K [Forestry Canada, Sault Ste. Marie, ON (Canada); Mitchell, M J [State Univ. of New York, Syracuse, NY (USA); Shepard, J P [National Council of the Paper Industry for Air and Stream Improvement, Gainesville, FL (USA)

    1992-01-01

    Annual nutrient fluxes within two forests exposed to acidic deposition were compared for a 1-year period. Calcium (Ca{sup 2+}) was the dominant cation in throughfall and soil solutions from tolerant hardwood dominated Spodosols (Podzols) at both Huntington Forest (HF), New York, and the Turkey Lakes watershed (TLW), Ontario. There was a net annual export of Ca{sup 2+} and Mg{sup 2+} from the TLW soil, whereas base cation inputs in precipitation equalled outputs at HF. In 1986, leaching losses of base cations were five times greater at TLW than at HF. A higher percentage of the base cation reserves was leached from the soil at TLW (5%) than at HF (1%). Relative to throughfall, aluminum concentrations increased in forest-floor and mineral-soil solutions, especially at HF. The TLW soil appears more sensitive to soil acidification. Deposited atmospheric acidity, however, was small in comparison with native soil acidity (total and exchangeable) and the reserves of base cations in each soil. Soil acidity and base saturation, therefore, are likely only to change slowly. 57 refs., 1 fig., 5 tabs.

  7. Spatial Upscaling of Soil Respiration under a Complex Canopy Structure in an Old‐Growth Deciduous Forest, Central Japan

    Directory of Open Access Journals (Sweden)

    Vilanee Suchewaboripont

    2017-01-01

    Full Text Available The structural complexity, especially canopy and gap structure, of old‐growth forests affects the spatial variation of soil respiration (Rs. Without considering this variation, the upscaling of Rs from field measurements to the forest site will be biased. The present study examined responses of Rs to soil temperature (Ts and water content (W in canopy and gap areas, developed the best fit modelof Rs and used the unique spatial patterns of Rs and crown closure to upscale chamber measurements to the site scale in an old‐growth beech‐oak forest. Rs increased with an increase in Ts in both gap and canopy areas, but the effect of W on Rs was different between the two areas. The generalized linear model (GLM analysis identified that an empirical model of Rs with thecoupling of Ts and W was better than an exponential model of Rs with only Ts. Moreover, because of different responses of Rs to W between canopy and gap areas, it was necessary to estimate Rs in these areas separately. Consequently, combining the spatial patterns of Rs and the crown closure could allow upscaling of Rs from chamber‐based measurements to the whole site in the present study.

  8. Simulated Seasonal Spatio-Temporal Patterns of Soil Moisture, Temperature, and Net Radiation in a Deciduous Forest

    Science.gov (United States)

    Ballard, Jerrell R., Jr.; Howington, Stacy E.; Cinnella, Pasquale; Smith, James A.

    2011-01-01

    The temperature and moisture regimes in a forest are key components in the forest ecosystem dynamics. Observations and studies indicate that the internal temperature distribution and moisture content of the tree influence not only growth and development, but onset and cessation of cambial activity [1], resistance to insect predation[2], and even affect the population dynamics of the insects [3]. Moreover, temperature directly affects the uptake and metabolism of population from the soil into the tree tissue [4]. Additional studies show that soil and atmospheric temperatures are significant parameters that limit the growth of trees and impose treeline elevation limitation [5]. Directional thermal infrared radiance effects have long been observed in natural backgrounds [6]. In earlier work, we illustrated the use of physically-based models to simulate directional effects in thermal imaging [7-8]. In this paper, we illustrated the use of physically-based models to simulate directional effects in thermal, and net radiation in a adeciduous forest using our recently developed three-dimensional, macro-scale computational tool that simulates the heat and mass transfer interaction in a soil-root-stem systems (SRSS). The SRSS model includes the coupling of existing heat and mass transport tools to stimulate the diurnal internal and external temperatures, internal fluid flow and moisture distribution, and heat flow in the system.

  9. Habitat properties are key drivers of Borrelia burgdorferi (s.l.) prevalence in Ixodes ricinus populations of deciduous forest fragments.

    Science.gov (United States)

    Ehrmann, Steffen; Ruyts, Sanne C; Scherer-Lorenzen, Michael; Bauhus, Jürgen; Brunet, Jörg; Cousins, Sara A O; Deconchat, Marc; Decocq, Guillaume; De Frenne, Pieter; De Smedt, Pallieter; Diekmann, Martin; Gallet-Moron, Emilie; Gärtner, Stefanie; Hansen, Karin; Kolb, Annette; Lenoir, Jonathan; Lindgren, Jessica; Naaf, Tobias; Paal, Taavi; Panning, Marcus; Prinz, Maren; Valdés, Alicia; Verheyen, Kris; Wulf, Monika; Liira, Jaan

    2018-01-08

    The tick Ixodes ricinus has considerable impact on the health of humans and other terrestrial animals because it transmits several tick-borne pathogens (TBPs) such as B. burgdorferi (sensu lato), which causes Lyme borreliosis (LB). Small forest patches of agricultural landscapes provide many ecosystem services and also the disservice of LB risk. Biotic interactions and environmental filtering shape tick host communities distinctively between specific regions of Europe, which makes evaluating the dilution effect hypothesis and its influence across various scales challenging. Latitude, macroclimate, landscape and habitat properties drive both hosts and ticks and are comparable metrics across Europe. Therefore, we instead assess these environmental drivers as indicators and determine their respective roles for the prevalence of B. burgdorferi in I. ricinus. We sampled I. ricinus and measured environmental properties of macroclimate, landscape and habitat quality of forest patches in agricultural landscapes along a European macroclimatic gradient. We used linear mixed models to determine significant drivers and their relative importance for nymphal and adult B. burgdorferi prevalence. We suggest a new prevalence index, which is pool-size independent. During summer months, our prevalence index varied between 0 and 0.4 per forest patch, indicating a low to moderate disservice. Habitat properties exerted a fourfold larger influence on B. burgdorferi prevalence than macroclimate and landscape properties combined. Increasingly available ecotone habitat of focal forest patches diluted and edge density at landscape scale amplified B. burgdorferi prevalence. Indicators of habitat attractiveness for tick hosts (food resources and shelter) were the most important predictors within habitat patches. More diverse and abundant macro- and microhabitat had a diluting effect, as it presumably diversifies the niches for tick-hosts and decreases the probability of contact between ticks

  10. Effects of structural complexity on within-canopy light environments and leaf traits in a northern mixed deciduous forest.

    Science.gov (United States)

    Fotis, Alexander T; Curtis, Peter S

    2017-10-01

    Canopy structure influences forest productivity through its effects on the distribution of radiation and the light-induced changes in leaf physiological traits. Due to the difficulty of accessing and measuring forest canopies, few field-based studies have quantitatively linked these divergent scales of canopy functioning. The objective of our study was to investigate how canopy structure affects light profiles within a forest canopy and whether leaves of mature trees adjust morphologically and biochemically to the light environments characteristic of canopies with different structural complexity. We used a combination of light detection and ranging (LiDAR) data and hemispherical photographs to quantify canopy structure and light environments, respectively, and a telescoping pole to sample leaves. Leaf mass per area (LMA), nitrogen on an area basis (Narea) and chlorophyll on a mass basis (Chlmass) were measured in red maple (Acer rubrum), american beech (Fagus grandifolia), white pine (Pinus strobus), and northern red oak (Quercus rubra) at different heights in plots with similar leaf area index but contrasting canopy complexity (rugosity). We found that more complex canopies had greater porosity and reduced light variability in the midcanopy while total light interception was unchanged relative to less complex canopies. Leaf phenotypes of F. grandifolia, Q. rubra and P. strobus were more sun-acclimated in the midstory of structurally complex canopies while leaf phenotypes of A. rubrum were more shade-acclimated (lower LMA) in the upper canopy of more complex stands, despite no differences in total light interception. Broadleaf species showed further differences in acclimation with increased Narea and reduced Chlmass in leaves with higher LMA, while P. strobus showed no change in Narea and Chlmass with higher LMA. Our results provide new insight on how light distribution and leaf acclimation in mature trees might be altered when natural and anthropogenic

  11. Environmental controls of daytime leaf carbon exchange: Implications for estimates of ecosystem fluxes in a deciduous forest

    Science.gov (United States)

    Heskel, M.; Tang, J.

    2017-12-01

    Leaf-level photosynthesis and respiration are sensitive to short- and long-term changed in temperature, and how these processes respond to phenological and seasonal transitions and daily temperature variation dictate how carbon is first assimilated and released in terrestrial ecosystems. We examined the short-term temperature response of daytime leaf carbon exchange at Harvard Forest across growing season, with the specific objective to quantify the light inhibition of dark respiration and photorespiration in leaves and use this to better inform daytime carbon assimilation and efflux estimates at the canopy scale. Dark and light respiration increased with measurement temperature and varied seasonally in a proportional manner, with the level of inhibition remaining relatively constant through the growing season. Higher rates of mitochondrial respiration and photorespiration at warmer temperatures drove a lower carbon use efficiency. Using temperature, light, and canopy leaf area index values to drive models, we estimate partitioned ecosystem fluxes and re-calculate gross primary production under multiple scenarios that include and exclude the impact of light inhibition, thermal acclimation, and seasonal variation in physiology. Quantifying the contribution of these `small fluxes' to ecosystem carbon exchange in forests provides a nuanced approach for integrating physiology into regional model estimates derived from eddy covariance and remote-sensing methods.

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

    Science.gov (United States)

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

    2016-12-01

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

  13. 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.

  14. 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.

  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. Three-year monitoring study of radiocesium transfer and ambient dose rate in forest environments affected by the Fukushima Dai-ichi Nuclear Power Plant accident

    Science.gov (United States)

    Kato, Hiroaki; Onda, Yuichi; Loffredo, Nicolas; Kawamori, Ayumi; Hisadome, Keigo

    2015-04-01

    We investigated the transfer of canopy-intercepted radiocesium to the forest floor during 3 years (July 2011~) following the Fukushima Dai-ichi Nuclear Power Plant accident. The cesium-137 (Cs-137) contents of throughfall, stemflow, and litterfall were monitored in two coniferous stands (plantation of Japanese cedar) and a deciduous broad-leaved forest stand (Japanese oak with red pine). We also measured an ambient dose rate at different height in the forest by using a survey meter (TCS-172B, Hitachi-Aloka Medical, LTD.) and a portable Ge gamma-ray detector (Detective-DX-100T, Ortec, Ametek, Inc.). Furthermore, effects of forest decontamination on the reduction of ambient dose rate were assessed quantitatively. Total Cs-137 deposition flux from the canopy to forest floor for the mature cedar, young cedar, and the mixed broad-leaved stands were 157 kBq/m^2, 167 kBq/m^2, and 54 kBq/m^2, respectively. These values correspond to 36%, 39% and 12% of total atmospheric input after the accident. The ambient dose rate showed an exponential decrease with time for all the forest sites, however the decreasing trend differed depending on the forest type. These data suggested that an ambient dose rate in forest environment can be variable in spatially and temporally reflecting the transfer of radiocesium from canopy to forest floor. We presented the analysis results of the relationship between radiocesium deposition flux and ambient dose rate at the forest floor. In addition to that, we reported the effects of forest decontamination (e.g., tree felling, removal of organic materials, woodchip pavement) on the reduction of ambient dose rate in the forest environment.

  18. The Effects of Detritus Input on Soil Organic Matter Content and Carbon Dioxide Emission in a Central European Deciduous Forest

    Directory of Open Access Journals (Sweden)

    FEKETE, István

    2011-01-01

    Full Text Available A major objective of our research was to survey soil biological activity and organic mattercontent reduction in a Central European oak forest during treatments of various detritus inputs within theSíkfkút DIRT (Detritus Input and Removal Treatments Project. Beside the control, three detritusremoval and two detritus duplication treatments were applied. Our examinations have proven that soilorganic matter content declined relatively fast in detritus removal treatments. The reduction wasespecially remarkable in root detritus removal treatments, where – due to the lack of transpiration – soilswere moister during the whole year than in the other treatments. The higher moisture content, despite ofthe reduction of detritus input, produced an intense soil respiration. This can be explained by the fact thatdecomposing organisms have increased the use of soil organic matter. Detritus input reduction had asignificantly greater effect on soil respiration and organic matter content than detritus input duplicationof the same extent. The latter did not cause any significant change compared to the control.

  19. An old-growth forest at the Caspian Sea coast is similar in epiphytic lichens to lowland deciduous forests in Central Europe

    Czech Academy of Sciences Publication Activity Database

    Ismailov, A.; Urbanavichus, G.; Vondrák, Jan; Pouska, V.

    2017-01-01

    Roč. 30, č. 1 (2017), s. 103-125 ISSN 0018-0971 Institutional support: RVO:67985939 Keywords : Dagestan * forest protection * lowland fores indicator Subject RIV: EF - Botanics OBOR OECD: Plant sciences, botany Impact factor: 0.740, year: 2016

  20. 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

  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

    Full Text Available O presente estudo objetivou determinar a suficiência amostral para coletas de serapilheira acumulada sobre o solo em povoamentos de Pinus elliottii, Eucalyptus sp., ambos plantados no Campus da Universidade Federal de Santa Maria e em uma área de Floresta Estacional Decidual (FED localizada no Morro do Elefante, Santa Maria, RS. Para a realização do estudo, foram coletadas 100 amostras de serapilheira por floresta, com o auxílio de uma moldura quadrada de 25 cm de lado, totalizando 300 amostras, as quais foram separadas nas seguintes frações: acículas ou folhas, galhos, estruturas reprodutivas, cascas e resíduos. Com base nos pesos de matéria seca de cada fração, realizou-se a análise estatística dos dados, visando à estabilização dos valores do coeficiente de variação (CV%. Para Pinus elliottii, a maior contribuição na formação da serapilheira foi dada pelas acículas, com 57,2%; em Eucalyptus sp., isso ocorreu com os galhos (38,8% e na FED, novamente com as folhas, que representaram 49,6% da serapilheira. No Pinus elliottii, o maior CV% se deu nos resíduos, seguido de estruturas reprodutivas. Em Eucalyptus sp., o maior CV% foi encontrado em cascas, seguido de galhos. Na FED, as cascas tiveram o maior CV%. A suficiência amostral necessária para Pinus elliottii foi de 40, sendo esse o povoamento que necessitou de menos amostras para estabilizar o CV%. Em Eucalyptus sp., a suficiência amostral foi de 70, enquanto na FED foram necessárias 80 amostras.This study determined the sample sufficiency for the collection of litter accumulated on the soil, in Pinus elliottii and Eucalyptus sp. stands, planted in the Campus of the Federal University of Santa Maria and a Seasonal Deciduous Forest, located at the "Morro do Elefante", Santa Maria - RS. To carry out this study, 100 samples were collected per site, using a square frame (25 cm², totaling 300 samples. The samples were separated in the following fractions: needles or

  2. Diversity, relative abundance and activity patterns of medium and large mammals in a tropical deciduous forest in the Isthmus of Tehuantepec, Oaxaca, Mexico

    Directory of Open Access Journals (Sweden)

    Malinalli Cortés-Marcial

    2014-12-01

    Full Text Available The use of camera traps and mammal track search are complementary methods to monitoring species of which is not well documented their natural history, as in the case of medium and large mammals. To ensure its conservation and good management, it is necessary to generate information about the structure of the community and their populations. The objective of the present study was to estimate the diversity, relative abundance and activity patterns of medium and large mammals in a tropical deciduous forest located in the Isthmus of Tehuantepec, Oaxaca, Mexico. Samplings were conducted in three month intervals, from September 2011 to May 2013. We used photographic-sampling and track search, two complementary sampling methods. For photographic-sampling, 12 camera traps were placed covering an area of 60km², while for the tracks search a monthly tour of four line-transect surveys of three kilometers length each was undertaken. We obtained a total of 344 pictures with 5 292 trap-days total sampling effort; in addition, 187 track records in a total of 144km. With both methods we registered 21 species of mammals, in 13 families and seven orders, and five species resulted in new records to the area. The diversity index of Shannon-Wiener obtained with the method of tracks was H´=2.41, while the most abundant species were Urocyon cinereoargenteus (IAR=0.23 and Pecari tajacu (IAR=0.20. By the method of trap the most abundant species were P. tajacu (IAR=2.62 and Nasua narica (IAR=1.28. In terms of patterns of activity P. tajacu, N. narica and Odocoileus virginianus were primarily diurnal species; Canis latrans and Leopardus pardalis did not show preference for any schedule in particular, and Didelphis virginiana and Dasypus novemcinctus preferred to have nocturnal activity. This information can be of help to the creation of programs of management and conservation of mammals of medium and large in the Isthmus of Tehuantepec, Oaxaca, México. Rev. Biol. Trop

  3. [Diversity, relative abundance and activity patterns of medium and large mammals in a tropical deciduous forest in the Isthmus of Tehuantepec, Oaxaca, Mexico].

    Science.gov (United States)

    Cortés-Marcial, Malinalli; Briones-Salas, Miguel

    2014-12-01

    The use of camera traps and mammal track search are complementary methods to monitoring species of which is not well documented their natural history, as in the case of medium and large mammals. To ensure its conservation and good management, it is necessary to generate information about the structure of the community and their populations. The objective of the present study was to estimate the diversity, relative abundance and activity patterns of medium and large mammals in a tropical deciduous forest located in the Isthmus of Tehuantepec, Oaxaca, Mexico. Samplings were conducted in three month intervals, from September 2011 to May 2013. We used photographic-sampling and track search, two complementary sampling methods. For photographic-sampling, 12 camera traps were placed covering an area of 60 km2, while for the tracks search a monthly tour of four line-transect surveys of three kilometers length each was undertaken. We obtained a total of 344 pictures with 5292 trap-days total sampling effort; in addition, 187 track records in a total of 144 km. With both methods we registered 21 species of mammals, in 13 families and seven orders, and five species resulted in new records to the area. The diversity index of Shannon-Wiener obtained with the method of tracks was H' = 2.41, while the most abundant species were Urocyon cinereoargen- teus (IAR = 0.23) and Pecari tajacu (IAR = 0.20). By the method of trap the most abundant species were P. tajacu (IAR = 2.62) and Nasua narica (IAR = 1.28). In terms of patterns of activity P. tajacu, N. narica and Odocoileus virginianus were primarily diurnal species; Canis latrans and Leopardus pardalis did not show preference for any schedule in particular, and Didelphis virginiana and Dasypus novemcinctus preferred to have nocturnal activity. This information can be of help to the creation of programs of management and conservation of mam- mals of medium and large in the Isthmus of Tehuantepec, Oaxaca, México.

  4. [Monitoring temporal dynamics in leaf area index of the temperate broadleaved deciduous forest in Maoershan region, Northeast China with tower-based radiation measurements.

    Science.gov (United States)

    Liu, Fan; Wang, Chuan Kuan; Wang, Xing Chang

    2016-08-01

    Broadband vegetation indices (BVIs) derived from routine radiation measurements on eddy flux towers have the advantage of high temporal resolutions, and thus have the potential to obtain detailed information of dynamics in canopy leaf area index (LAI). Taking the temperate broadleaved deciduous forest around the Maoershan flux tower in Northeast China as a case, we investigated the controlling factors and smoothing method of four BVI time-series, i.e., broadband norma-lized difference vegetation index (NDVI B ), broadband enhanced vegetation index (EVI B ), the ratio of the near-infrared radiation reflectance to photosynthetically active radiation reflectance (SR NP ), and the ratio of the shortwave radiation reflectance to photosynthetically active radiation reflectance (SR SP ). We compared the seasonal courses of the BVIs with the LAI based on litterfall collection method. The values for each BVI were slightly different among the three calculation methods by Huemmrich, Wilson, and Jenkins, but showed similar seasonal patterns. The diurnal variations in BVIs were mainly influenced by the solar elevation and the angle between the solar elevation and slope, but the BVIs were relatively stable around 12:30. The noise of daily BVI time-series could be effectively smoothed by a threshold of clearness index (K). The seasonal courses of BVIs for each time of day around the noon had similar patterns, but their thresholds of K and the percen-tages of remaining data were different. Therefore, the daily values of BVIs might be optimized based on the smoothing and the proportion of remaining data. The NDVI B was closely correlated linearly with the LAI derived from the litterfall collection method, while the EVI B , SR NP , and SR SP had a logarithmic relationship with the LAI. The NDVI B had the advantage in tracking the seasonal dyna-mics in LAI and extrapolating LAI to a broader scale. Given that most eddy flux towers had equipped with energy balance measurements, a

  5. 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

  6. Deciduous Forest Zone of Ghana

    African Journals Online (AJOL)

    carbon, nitrogen and phosphorus contents, soil reaction and base saturation with highest values in the topsoil due to the .... These soils occur extensively in the. Zone ... tion with 6M sulphuric acid. .... which will lead to removal of topsoil litter,.

  7. 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

  8. FLORÍSTICA E ESTRUTURA EM ÁREA DE FLORESTA ESTACIONAL DECIDUAL NA REGIÃO DO ALTO URUGUAI, RS / FLORISTIC AND STRUCTURE IN AREA OF SEASONAL DECIDUOUS FOREST IN THE REGION OF THE ALTO URUGUAI, RS

    Directory of Open Access Journals (Sweden)

    F. R. Lambrecht

    2016-06-01

    Full Text Available           O trabalho teve como objetivos realizar a análise florística das estruturas horizontal e vertical em um fragmento de Floresta Estacional Decidual (FED na região do Alto Uruguai, em Frederico Westphalen, RS, Brasil. Foi realizado um censo em uma área amostral de 10.000 m², subdividida em 100 subparcelas de 10x10 m. Realizou-se a mensuração e a identificação de todos os indivíduos de espécies arbóreas com circunferência a altura do peito (CAP≥ 31,4cm. Com os dados obtidos, foram realizados cálculos de densidade (D, frequência (F, dominância (Do, índice de valor de importância (IVI, índice de valor de cobertura (IVC e a estratificação dos indivíduos. O maior número de espécies concentrou-se na família Fabaceae (10 e o maior número de indivíduos na família Meliaceae (147 ou 25,3%. Trichilia claussenii C. DC. Nectandra megapotamica (Spreng. Mez, Achatocarpus praecox Griseb. e Eugenia rostrifolia D. Legrand representaram 38,28% da densidade relativa e Holocalyx balansae Micheli, Trichilia claussenii, Nectandra megapotamica, Cordia americana (L. Gottshling & J.E.Mill., Phytolacca dioica  L., Achatocarpus praecox, e Eugenia rostrifolia representaram 50,5% da dominância relativa. Considerando a estrutura vertical, as sete espécies mais frequentes apresentaram uma maior quantidade de indivíduos no estrato médio. Conclui-se que a área florestal encontra-se em estágio intermediário de sucessão.

  9. Natural and near natural tropical forest values

    Science.gov (United States)

    Daniel H. Henning

    2011-01-01

    This paper identifies and describes some of the values associated with tropical rain forests in their natural and near-natural conditions. Tropical rain forests are moist forests in the humid tropics where temperature and rainfall are high and the dry season is short. These closed (non-logged) and broad-leaved forests are a global resource. Located almost entirely in...

  10. 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

  11. Fatty acid profiles of great tit ( Parus major) eggs differ between urban and rural habitats, but not between coniferous and deciduous forests

    Science.gov (United States)

    Toledo, Alejandra; Andersson, Martin N.; Wang, Hong-Lei; Salmón, Pablo; Watson, Hannah; Burdge, Graham C.; Isaksson, Caroline

    2016-08-01

    Early-life nutrition is an important determinant of both short- and long-term performance and fitness. The avian embryo develops within an enclosed package of nutrients, of which fatty acids (FA) are essential for many aspects of development. The FA composition of yolk depends on maternal nutrition and condition prior to egg formation, which may be affected by the external environment. To test if maternal environment affects yolk FA composition, we investigated whether the FA composition of great tit ( Parus major) egg yolks differed between urban and rural habitats, and between deciduous and coniferous habitats. The results reveal differences in FA composition between eggs laid in urban and rural habitats, but not between eggs from the coniferous and deciduous habitats. To a large extent, this difference likely reflects dietary differences associated with urban habitats rather than dominating vegetation type. Specifically, urban yolks contained lower proportions of both ω-3 and ω-6 polyunsaturated FAs (PUFA), which are important for chick development. We also found a positive association between the proportion of saturated fatty acids and laying date, and a negative association between the proportion of ω-6 PUFA and clutch size. Given that urbanization is expanding rapidly, future studies should investigate whether factors such as anthropogenic food in the urban environment underlie these differences and whether they impair chick development.

  12. Mechanisms and rates of atmospheric deposition of selected trace elements and sulfate to a deciduous forest watershed. [Roles of dry and wet deposition concentrations measured in Walker Branch Watershed

    Energy Technology Data Exchange (ETDEWEB)

    Lindberg, S.E.; Harriss, R.C.; Turner, R.R.; Shriner, D.S.; Huff, D.D.

    1979-06-01

    The critical links between anthropogenic emissions to the atmosphere and their effects on ecosystems are the mechanisms and rates of atmospheric deposition. The atmospheric input of several trace elements and sulfate to a deciduous forest canopy is quantified and the major mechanisms of deposition are determined. The study area was Walker Branch Watershed (WBW) in eastern Tennessee. The presence of a significant quantity of fly ash and dispersed soil particles on upward-facing leaf and flat surfaces suggested sedimentation to be a major mechanism of dry deposition to upper canopy elements. The agreement for deposition rates measured to inert, flat surfaces and to leaves was good for Cd, SO/sub 4//sup =/, Zn, and Mn but poor for Pb. The precipitation concentrations of H/sup +/, Pb, Mn, and SO/sub 4//sup =/ reached maximum values during the summer months. About 90% of the wet deposition of Pb and SO/sub 4//sup =/ was attributed to scavenging by in-cloud processes while for Cd and Mn, removal by in-cloud scavenging accounted for 60 to 70% of the deposition. The interception of incoming rain by the forest canopy resulted in a net increase in the concentrations of Cd, Mn, Pb, Zn, and SO/sub 4//sup =/ but a net decrease in the concentration of H/sup +/. The source of these elements in the forest canopy was primarily dry deposited aerosols for Pb, primarily internal plant leaching for Mn, Cd, and Zn, and an approximately equal combination of the two for SO/sub 4//sup =/. Significant fractions of the total annual elemental flux to the forest floor in a representative chestnut oak stand were attributable to external sources for Pb (99%), Zn (44%), Cd (42%), SO/sub 4//sup =/ (39%), and Mn (14%), the remainder being related to internal element cycling mechanisms. On an annual scale the dry deposition process constituted a significant fraction of the total atmospheric input. (ERB)

  13. From Leaf Synthesis to Senescence: n-Alkyl Lipid Abundance and D/H Composition Among Plant Species in a Temperate Deciduous Forest at Brown's Lake Bog, Ohio, USA

    Science.gov (United States)

    Freimuth, E. J.; Diefendorf, A. F.; Lowell, T. V.

    2014-12-01

    The hydrogen isotope composition (D/H, δD) of terrestrial plant leaf waxes is a promising paleohydrology proxy because meteoric water (e.g., precipitation) is the primary hydrogen source for wax synthesis. However, secondary environmental and biological factors modify the net apparent fractionation between precipitation δD and leaf wax δD, limiting quantitative reconstruction of paleohydrology. These secondary factors include soil evaporation, leaf transpiration, biosynthetic fractionation, and the seasonal timing of lipid synthesis. Here, we investigate the influence of each of these factors on n-alkyl lipid δD in five dominant deciduous angiosperm tree species as well as shrubs, ferns and grasses in the watershed surrounding Brown's Lake Bog, Ohio, USA. We quantified n-alkane and n-alkanoic acid concentrations and δD in replicate individuals of each species at weekly to monthly intervals from March to October 2014 to assess inter- and intraspecific isotope variability throughout the growing season. We present soil, xylem and leaf water δD from each individual, and precipitation and atmospheric water vapor δD throughout the season to directly examine the relationship between source water and lipid isotope composition. These data allow us to assess the relative influence of soil evaporation and leaf transpiration among plant types, within species, and along a soil moisture gradient throughout the catchment. We use leaf water δD to approximate biosynthetic fractionation for each individual and test whether this is a species-specific and seasonal constant, and to evaluate variation among plant types with identical growth conditions. Our high frequency sampling approach provides new insights into the seasonal timing of n-alkane and n-alkanoic acid synthesis and subsequent fluctuations in concentration and δD in a temperate deciduous forest. These results will advance understanding of the magnitude and timing of secondary influences on the modern leaf wax

  14. Regeneration of different plant functional types in a Masson pine forest following pine wilt disease.

    Science.gov (United States)

    Hu, Guang; Xu, Xuehong; Wang, Yuling; Lu, Gao; Feeley, Kenneth J; Yu, Mingjian

    2012-01-01

    Pine wilt disease is a severe threat to the native pine forests in East Asia. Understanding the natural regeneration of the forests disturbed by pine wilt disease is thus critical for the conservation of biodiversity in this realm. We studied the dynamics of composition and structure within different plant functional types (PFTs) in Masson pine forests affected by pine wilt disease (PWD). Based on plant traits, all species were assigned to four PFTs: evergreen woody species (PFT1), deciduous woody species (PFT2), herbs (PFT3), and ferns (PFT4). We analyzed the changes in these PFTs during the initial disturbance period and during post-disturbance regeneration. The species richness, abundance and basal area, as well as life-stage structure of the PFTs changed differently after pine wilt disease. The direction of plant community regeneration depended on the differential response of the PFTs. PFT1, which has a higher tolerance to disturbances, became dominant during the post-disturbance regeneration, and a young evergreen-broad-leaved forest developed quickly after PWD. Results also indicated that the impacts of PWD were dampened by the feedbacks between PFTs and the microclimate, in which PFT4 played an important ecological role. In conclusion, we propose management at the functional type level instead of at the population level as a promising approach in ecological restoration and biodiversity conservation.

  15. Validation of PROBA-V GEOV1 and MODIS C5 & C6 fAPAR Products in a Deciduous Beech Forest Site in Italy

    Czech Academy of Sciences Publication Activity Database

    Nestola, E.; Sanchez-Zapero, J.; Latorre, C.; Mazzenga, F.; Matteucci, G.; Calfapietra, Carlo; Camacho, F.

    2017-01-01

    Roč. 9, č. 2 (2017), č. článku 126. ISSN 2072-4292 Institutional support: RVO:86652079 Keywords : fAPAR * validation * PROBA-V GEOV1 * MODIS C5 * MODIS C6 * beech forest * up-scaling * GCOS requirements * in-situ comparison and evaluation Subject RIV: EH - Ecology, Behaviour OBOR OECD: Environmental sciences (social aspects to be 5.7) Impact factor: 3.244, year: 2016

  16. Climate- and successional-related changes in functional composition of European forests are strongly driven by tree mortality.

    Science.gov (United States)

    Ruiz-Benito, Paloma; Ratcliffe, Sophia; Zavala, Miguel A; Martínez-Vilalta, Jordi; Vilà-Cabrera, Albert; Lloret, Francisco; Madrigal-González, Jaime; Wirth, Christian; Greenwood, Sarah; Kändler, Gerald; Lehtonen, Aleksi; Kattge, Jens; Dahlgren, Jonas; Jump, Alistair S

    2017-10-01

    Intense droughts combined with increased temperatures are one of the major threats to forest persistence in the 21st century. Despite the direct impact of climate change on forest growth and shifts in species abundance, the effect of altered demography on changes in the composition of functional traits is not well known. We sought to (1) quantify the recent changes in functional composition of European forests; (2) identify the relative importance of climate change, mean climate and forest development for changes in functional composition; and (3) analyse the roles of tree mortality and growth underlying any functional changes in different forest types. We quantified changes in functional composition from the 1980s to the 2000s across Europe by two dimensions of functional trait variation: the first dimension was mainly related to changes in leaf mass per area and wood density (partially related to the trait differences between angiosperms and gymnosperms), and the second dimension was related to changes in maximum tree height. Our results indicate that climate change and mean climatic effects strongly interacted with forest development and it was not possible to completely disentangle their effects. Where recent climate change was not too extreme, the patterns of functional change generally followed the expected patterns under secondary succession (e.g. towards late-successional short-statured hardwoods in Mediterranean forests and taller gymnosperms in boreal forests) and latitudinal gradients (e.g. larger proportion of gymnosperm-like strategies at low water availability in forests formerly dominated by broad-leaved deciduous species). Recent climate change generally favoured the dominance of angiosperm-like related traits under increased temperature and intense droughts. Our results show functional composition changes over relatively short time scales in European forests. These changes are largely determined by tree mortality, which should be further

  17. Hyper-temporal c-band SAR for baseline woody structural assessments in deciduous savannas

    CSIR Research Space (South Africa)

    Mathieu, Renaud SA

    2016-08-01

    Full Text Available deciduous savanna environment. Results showed that: the temporal filter reduced image variance; the random forest model out-performed the linear model; while the TCV metric consistently showed marginally higher accuracies than the TCC metric. Combinations...

  18. Outbreaks of forest defoliating insects in Japan, 1950-2000.

    Science.gov (United States)

    Kamata, N; Kamata, N

    2002-04-01

    In Japan, several forest-defoliating insects reach outbreak levels and cause serious defoliation. Stand mortality sometimes occurs after severe defoliation. However, in general, tree mortality caused by insect defoliation is low because of the prevailing moist climate in Japan. Evergreen conifers are more susceptible to tree mortality as a result of insect defoliation whereas deciduous broad-leaved trees are seldom killed. Insect defoliation occurs more frequently in man-made environments such as among shade trees, orchards, and plantations than in natural habitats. Outbreaks of some defoliators tend to occur in stands of a particular age: e.g. outbreaks of the pine caterpillar, Dendrolimus spectabilis Butler (Lepidoptera: Lasiocampidae) occur more frequently in young pine plantations. In contrast, defoliation caused by outbreaks of lepidopterous and hymenopterous pests in larch plantations is more frequent with stand maturation. There is a relationship between outbreaks of some defoliators and altitude above sea level. Most outbreaks of forest defoliators were terminated by insect pathogens that operated in a density-dependent fashion. Since the 1970s, Japan has been prosperous and can afford to buy timber from abroad. More recently, there has been an increasing demand for timber in Japan, that coincides with a huge demand internationally, so that the country will need to produce more timber locally in the future. The increasing pressure on the forestry industry to meet this demand will require more sophisticated methods of pest control coupled with more sustainable methods of silviculture.

  19. Levantamento florístico de uma mata decídua em Uberlândia, Minas Gerais, Brasil Floriste survey of an area of deciduous forest in Uberlândia, Minas Gerais, Brazil

    Directory of Open Access Journals (Sweden)

    Luciene Alves Rodrigues

    1997-12-01

    Full Text Available Esse trabalho consistiu de levantamento florístico em mata mesófila decídua situada em solo raso de origem basáltica em Uberlândia, Minas Gerais. Foram feitas visitas quinzenais à mata, no período de fevereiro/93 a junho/95, para coletas de exemplares botânicos férteis. O material coletado foi incorporado ao Herbário da Universidade Federal de Uberlândia (HUFU. Foram identificadas 105 espécies de árvores, arbustos, lianas e herbáceas, distribuídas em 88 gêneros e 43 famílias. As espécies mais freqüentes na mata foram: Anadenanthera colubrina, Bauhinia sp., Croton sp., Myracrodruon urundeuva e Sweetiafruticosa. Euphorbiaceae (10, Rubiaceae (8, Mimosaceae (6, Myrtaceae (6, Caesalpinaceae (5 e Fabaceae (5 foram as famílias com maior número de espécies identificadas.A floristic survey was carried out in a deciduous forest on a shallow basaltic soil, in Uberlândia, Minas Gerais. Visits were performed fortnightly from February/93 to June/95. The sampled material was lodged at the Herbarium of the Universidade Federal de Uberlândia (HUFU. A list is provided with 105 species of trees, shrubs, scandent shrubs, lianas and herbs, belonging to 88 genera and 43 botanic families. The most frequent species were: Anadenanthera colubrina, Bauhinia sp., Croton sp., Myracrodruon urundeuva and Sweetia fruticosa. Euphorbiaceae (10, Rubiaceae (8, Mimosaceae (6, Myrtaceae (6, Caesalpinaceae (5 e Fabaceae (5 were the families with the largest numbers of identified species.

  20. Beyond leaf color: Comparing camera-based phenological metrics with leaf biochemical, biophysical, and spectral properties throughout the growing season of a temperate deciduous forest

    Science.gov (United States)

    Yang, Xi; Tang, Jianwu; Mustard, John F.

    2014-03-01

    Plant phenology, a sensitive indicator of climate change, influences vegetation-atmosphere interactions by changing the carbon and water cycles from local to global scales. Camera-based phenological observations of the color changes of the vegetation canopy throughout the growing season have become popular in recent years. However, the linkages between camera phenological metrics and leaf biochemical, biophysical, and spectral properties are elusive. We measured key leaf properties including chlorophyll concentration and leaf reflectance on a weekly basis from June to November 2011 in a white oak forest on the island of Martha's Vineyard, Massachusetts, USA. Concurrently, we used a digital camera to automatically acquire daily pictures of the tree canopies. We found that there was a mismatch between the camera-based phenological metric for the canopy greenness (green chromatic coordinate, gcc) and the total chlorophyll and carotenoids concentration and leaf mass per area during late spring/early summer. The seasonal peak of gcc is approximately 20 days earlier than the peak of the total chlorophyll concentration. During the fall, both canopy and leaf redness were significantly correlated with the vegetation index for anthocyanin concentration, opening a new window to quantify vegetation senescence remotely. Satellite- and camera-based vegetation indices agreed well, suggesting that camera-based observations can be used as the ground validation for satellites. Using the high-temporal resolution dataset of leaf biochemical, biophysical, and spectral properties, our results show the strengths and potential uncertainties to use canopy color as the proxy of ecosystem functioning.

  1. Inversely estimating the vertical profile of the soil CO2 production rate in a deciduous broadleaf forest using a particle filtering method.

    Science.gov (United States)

    Sakurai, Gen; Yonemura, Seiichiro; Kishimoto-Mo, Ayaka W; Murayama, Shohei; Ohtsuka, Toshiyuki; Yokozawa, Masayuki

    2015-01-01

    Carbon dioxide (CO2) efflux from the soil surface, which is a major source of CO2 from terrestrial ecosystems, represents the total CO2 production at all soil depths. Although many studies have estimated the vertical profile of the CO2 production rate, one of the difficulties in estimating the vertical profile is measuring diffusion coefficients of CO2 at all soil depths in a nondestructive manner. In this study, we estimated the temporal variation in the vertical profile of the CO2 production rate using a data assimilation method, the particle filtering method, in which the diffusion coefficients of CO2 were simultaneously estimated. The CO2 concentrations at several soil depths and CO2 efflux from the soil surface (only during the snow-free period) were measured at two points in a broadleaf forest in Japan, and the data were assimilated into a simple model including a diffusion equation. We found that there were large variations in the pattern of the vertical profile of the CO2 production rate between experiment sites: the peak CO2 production rate was at soil depths around 10 cm during the snow-free period at one site, but the peak was at the soil surface at the other site. Using this method to estimate the CO2 production rate during snow-cover periods allowed us to estimate CO2 efflux during that period as well. We estimated that the CO2 efflux during the snow-cover period (about half the year) accounted for around 13% of the annual CO2 efflux at this site. Although the method proposed in this study does not ensure the validity of the estimated diffusion coefficients and CO2 production rates, the method enables us to more closely approach the "actual" values by decreasing the variance of the posterior distribution of the values.

  2. 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

  3. Top-down control of herbivory by birds and bats in the canopy of temperate broad-leaved oaks (Quercus robur.

    Directory of Open Access Journals (Sweden)

    Stefan M Böhm

    2011-04-01

    Full Text Available The intensive foraging of insectivorous birds and bats is well known to reduce the density of arboreal herbivorous arthropods but quantification of collateral leaf damage remains limited for temperate forest canopies. We conducted exclusion experiments with nets in the crowns of young and mature oaks, Quercus robur, in south and central Germany to investigate the extent to which aerial vertebrates reduce herbivory through predation. We repeatedly estimated leaf damage throughout the vegetation period. Exclusion of birds and bats led to a distinct increase in arthropod herbivory, emphasizing the prominent role of vertebrate predators in controlling arthropods. Leaf damage (e.g., number of holes differed strongly between sites and was 59% higher in south Germany, where species richness of vertebrate predators and relative oak density were lower compared with our other study site in central Germany. The effects of bird and bat exclusion on herbivory were 19% greater on young than on mature trees in south Germany. Our results support previous studies that have demonstrated clear effects of insectivorous vertebrates on leaf damage through the control of herbivorous arthropods. Moreover, our comparative approach on quantification of leaf damage highlights the importance of local attributes such as tree age, forest composition and species richness of vertebrate predators for control of arthropod herbivory.

  4. impact of re-forestation of a re-growth secondary forest with

    African Journals Online (AJOL)

    BIG TIMMY

    In general, the forest stand had more density of trees in each dbh class with a peak in .... Awolowo University Estate, Ile-Ife, Osun state, ... forest sub-type is dry deciduous forest (Onochie, ..... eastern Cascades, USA. .... Agriculture, Washington.

  5. Comparative seasonal variations of spectral signatures of broad-leaved and coniferous stands from Landsat data. Comparison with other perennial environments; Evolutions saisonnières comparées des signatures spectrales de feuillus et de conifères à partir de données Landsat : comparaison avec d'autres milieux pérennes

    Energy Technology Data Exchange (ETDEWEB)

    Chaume, R. [Office de la Recherche Scientifique et Technique Outre-Mer, Bondy (France); Combeau, A.

    1984-07-01

    Spectral signatures of two distinct forest test areas were identified from digital data including 15 LANDSAT scenes covering the same geographical area: a broad-leaved forest (oak and beech) and a coniferous forest (scotch pine). Seasonal variations of the signatures were examined and were expressed in terms of various data: date, solar height and phenological state of vegetation cover. Results were compared to these obtained from other perennial surface conditions (grassland, bare soils) . Range of the seasonal variations of radiance is noted, as well as evolutionary peculiarities on each band and between themes. Rationing of spectral bands (particularly MSS 5 and 7) and their variation with time are specified [French] A partir des données numériques de 15 scènes LANDSAT sur un même secteur géographique, l e s auteurs définissent les signatures spectrales de deux milieux forestiers distincts: une futaie de chênes-hêtres et une futaie de pins sylvestres, et ils étudient l a variation saisonnière de ces signatures. Ils tentent d'interpréter cette variabilité en fonction de la date de saisie des données, donc de l a hauteur du soleil et de l'état phénologique du couvert végétal. Ils comparent les résultats 5 ceux obtenus sur d'autres milieux pérennes (prairie, sols nus). L'amplitude des variations saisonnières des luminances est précisée, ainsi que les modalités particulières de l'évolution sur certains canaux ou entre les deux thèmes. Les auteurs étudient également les rapports de luminance inter-canaux (5 et 7 en particulier) et leur évolution dans le temps.

  6. DRY DEPOSITION OF POLLUTANTS TO FORESTS

    Science.gov (United States)

    We report on the results of an extensive field campaign to measure dry deposition of ozone and sulfur dioxide to a sample of forest types in the United States. Measurements were made for full growing seasons over a deciduous forest in Pennsylvania and a mixed deciduous-conifer...

  7. Forests

    Science.gov (United States)

    Louis R. Iverson; Mark W. Schwartz

    1994-01-01

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

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

    Directory of Open Access Journals (Sweden)

    JEROEN STAELENS

    2011-03-01

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

  9. [Soil organic carbon pools and their turnover under two different types of forest in Xiao-xing'an Mountains, Northeast China].

    Science.gov (United States)

    Gao, Fei; Jiang, Hang; Cui, Xiao-yang

    2015-07-01

    Soil samples collected from virgin Korean pine forest and broad-leaved secondary forest in Xiaoxing'an Mountains, Northeast China were incubated in laboratory at different temperatures (8, 18 and 28 °C) for 160 days, and the data from the incubation experiment were fitted to a three-compartment, first-order kinetic model which separated soil organic carbon (SOC) into active, slow, and resistant carbon pools. Results showed that the soil organic carbon mineralization rates and the cumulative amount of C mineralized (all based on per unit of dry soil mass) of the broad-leaved secondary forest were both higher than that of the virgin Korean pine forest, whereas the mineralized C accounted for a relatively smaller part of SOC in the broad-leaved secondary forest soil. Soil active and slow carbon pools decreased with soil depth, while their proportions in SOC increased. Soil resistant carbon pool and its contribution to SOC were both greater in the broad-leaved secondary forest soil than in the virgin Korean pine forest soil, suggesting that the broad-leaved secondary forest soil organic carbon was relatively more stable. The mean retention time (MRT) of soil active carbon pool ranged from 9 to 24 d, decreasing with soil depth; while the MRT of slow carbon pool varied between 7 and 24 a, increasing with soil depth. Soil active carbon pool and its proportion in SOC increased linearly with incubation temperature, and consequently, decreased the slow carbon pool. Virgin Korean pine forest soils exhibited a higher increasing rate of active carbon pool along temperature gradient than the broad-leaved secondary forest soils, indicating that the organic carbon pool of virgin Korean pine forest soil was relatively more sensitive to temperature change.

  10. 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.

  11. Response of Termite (Blattodea: Termitoidae) Assemblages to Lower Subtropical Forest Succession: A Case Study in Dinghushan Biosphere Reserve, China.

    Science.gov (United States)

    Li, Zhi-Qiang; Ke, Yun-Ling; Zeng, Wen-Hui; Zhang, Shi-Jun; Wu, Wen-Jing

    2016-02-01

    Termite (Blattodea: Termitoidae) assemblages have important ecological functions and vary in structure between habitats, but have not been studied in lower subtropical forests. To examine whether differences in the richness and relative abundance of termite species and functional groups occur in lower subtropical regions, termite assemblages were sampled in Dinghushan Biosphere Reserve, China, among pine forest, pine and broad-leaved mixed forest (mixed forest), and monsoon evergreen broad-leaved forest (monsoon forest). The dominant functional group was wood-feeding termites (family Termitidae), and the mixed forest hosted the greatest richness and relative abundance. Soil-feeding termites were absent from the lower subtropical system, while humus-feeding termites were sporadically distributed in mixed forest and monsoon forest. The species richness and functional group abundance of termites in our site may be linked to the forest succession. Altitude, soil temperature, air temperature, surface air relative humidity, and litter depth were significant influences on species and functional group diversity.

  12. 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.

  13. [Carbon storage of forest stands in Shandong Province estimated by forestry inventory data].

    Science.gov (United States)

    Li, Shi-Mei; Yang, Chuan-Qiang; Wang, Hong-Nian; Ge, Li-Qiang

    2014-08-01

    Based on the 7th forestry inventory data of Shandong Province, this paper estimated the carbon storage and carbon density of forest stands, and analyzed their distribution characteristics according to dominant tree species, age groups and forest category using the volume-derived biomass method and average-biomass method. In 2007, the total carbon storage of the forest stands was 25. 27 Tg, of which the coniferous forests, mixed conifer broad-leaved forests, and broad-leaved forests accounted for 8.6%, 2.0% and 89.4%, respectively. The carbon storage of forest age groups followed the sequence of young forests > middle-aged forests > mature forests > near-mature forests > over-mature forests. The carbon storage of young forests and middle-aged forests accounted for 69.3% of the total carbon storage. Timber forest, non-timber product forest and protection forests accounted for 37.1%, 36.3% and 24.8% of the total carbon storage, respectively. The average carbon density of forest stands in Shandong Province was 10.59 t x hm(-2), which was lower than the national average level. This phenomenon was attributed to the imperfect structure of forest types and age groups, i. e., the notably higher percentage of timber forests and non-timber product forest and the excessively higher percentage of young forests and middle-aged forest than mature forests.

  14. Pregnancy immunology: decidual immune cells.

    Science.gov (United States)

    Sanguansermsri, Donruedee; Pongcharoen, Sutatip

    2008-01-01

    Human pregnancy is a complex process. Placental development depends on the function of secretory molecules produced by placental trophoblast cells as well as by maternal uterine immune cells within the decidua. These decidual immune cells are T cells, natural killer cells, macrophages and dendritic cells. The interactions between the trophoblast cells and the maternal immune cells have an impact on the outcome of the pregnancy. Knowledge about the phenotypes and functions of the maternal immune cells in normal and pathological pregnancies including recurrent spontaneous abortions, preeclampsia and hydatidiform moles may improve our understanding of the immunobiology of the normal pregnancy as a whole and may provide approaches for improving the treatment of pathological pregnancies.

  15. Nitrous oxide emission inventory of German forest soils

    Science.gov (United States)

    Schulte-Bisping, Hubert; Brumme, Rainer; Priesack, Eckart

    2003-02-01

    Annual fluxes of N2O trace gas emissions were assessed after stratifying German forest soils into Seasonal Emission Pattern (SEP) and Background Emission Pattern (BEP). Broad-leaved forests with soil pH(KCl) ≤ 3.3 were assigned to have SEP, broad-leaved forests with soil pH(KCl) > 3.3 and all needle-leaved forests to have BEP. BEPs were estimated by a relationship between annual N2O emissions and carbon content of the O-horizon. SEPs were primarily controlled by temperature and moisture and simulated by the model Expert-N after calibration to a 9-year record of N2O measurements. Analysis with different climate and soil properties indicated that the model reacts highly sensitive to changes in soil temperature, soil moisture, and soil texture. A geographic information system (ARC/INFO) was used for a spatial resolution of 1 km × 1 km grid where land cover, dominant soil units, and hygro climate classes were combined. The mean annual N2O emission flux from German forest soils was estimated as 0.32 kg ha-1 yr-1. Broad-leaved forests with SEP had the highest emissions (2.05 kg ha-1 yr-1) followed by mixed forests (0.38 kg ha-1 yr-1), broad-leaved forests (0.37 kg ha-1 yr-1), and needle-leaved forests with BEP (0.17 kg ha-1 yr-1). The annual N2O emission from German forest soils was calculated as 3.26 Gg N2O-N yr-1. Although needle-leaved trees cover about 57% of the entire forest area in Germany, their contribution is low (0.96 Gg N2O-N yr-1). Broad-leaved forests cover about 22% of the forest area but have 55% higher emissions (1.49 Gg N2O-N yr-1) than needle-leaved. Mixed forests cover 21% of the area and contribute 0.81 Gg N2O-N yr-1. Compared to the total N2O emissions in Germany of 170 Gg N yr-1, forest soils contribute only 1.9%. However, there are some uncertainties in this emission inventory, which are intensely discussed.

  16. ABOVEGROUND BIOMASS DISTRIBUTION OF US EASTERN HARDWOOD FORESTS AND THE USE OF LARGE TREES AS AN INDICATOR OF FOREST DEVELOPMENT

    Science.gov (United States)

    Past clearing and harvesting of the deciduous hardwood forests of eastern USA released large amount of carbon dioxide into the atmosphere, but through recovery and regrowth these forests are now accumulating atmospheric carbon (C). This study examined quantities and distribution ...

  17. [Characteristics of wintering in ground beetles (Coleoptera, Carabidae) in forest ecosystems of the East European Plain].

    Science.gov (United States)

    Griuntal', S Iu

    2000-01-01

    Specific features of wintering of the ground beetles in three habitats (litter, soil, and bark of fallen trees and stumps) were comparatively studied in the forests of forest-steppe (Voronezh District) and subzone of broad-leaved-spruce forests (Moscow District). The main mass of ground beetles is concentrated in the upper 10-cm soil layer, irrespective of the type of watering (automorphous or hydromorphous soils). Wintering under the bark is a facultative feature of the most species occurring in these biocoenoses.

  18. 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.

  19. Forests

    International Nuclear Information System (INIS)

    Melin, J.

    1997-01-01

    Forests have the capacity to trap and retain radionuclides for a substantial period of time. The dynamic behaviour of nutrients, pollution and radionuclides in forests is complex. The rotation period of a forest stand in the Nordic countries is about 100 years, whilst the time for decomposition of organic material in a forest environment can be several hundred years. This means that any countermeasure applied in the forest environment must have an effect for several decades, or be reapplied continuously for long periods of time. To mitigate the detrimental effect of a contaminated forest environment on man, and to minimise the economic loss in trade of contaminated forest products, it is necessary to understand the mechanisms of transfer of radionuclides through the forest environment. It must also be stressed that any countermeasure applied in the forest environment must be evaluated with respect to long, as well as short term, negative effects, before any decision about remedial action is taken. Of the radionuclides studied in forests in the past, radiocaesium has been the main contributor to dose to man. In this document, only radiocaesium will be discussed since data on the impact of other radionuclides on man are too scarce for a proper evaluation. (EG)

  20. Forest influences on snow accumulation and snowmelt at the Hubbard Brook Experimental Forest, New Hampshire, USA

    Science.gov (United States)

    Colin A. Penn; Beverley C. Wemple; John L. Campbell

    2012-01-01

    Many factors influence snow depth, water content and duration in forest ecosystems. The effects of forest cover and canopy gap geometry on snow accumulation has been well documented in coniferous forests of western North America and other regions; however, few studies have evaluated these effects on snowpack dynamics in mixed deciduous forests of the northeastern USA....

  1. Gaseous mercury fluxes from forest soils in response to forest harvesting intensity: A field manipulation experiment

    Science.gov (United States)

    M. Mazur; C.P.J. Mitchell; C.S. Eckley; S.L. Eggert; R.K. Kolka; S.D. Sebestyen; E.B. Swain

    2014-01-01

    Forest harvesting leads to changes in soil moisture, temperature and incident solar radiation, all strong environmental drivers of soil-air mercury (Hg) fluxes. Whether different forest harvesting practices significantly alter Hg fluxes from forest soils is unknown.We conducted a field-scale experiment in a northern Minnesota deciduous forest wherein gaseous Hg...

  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. 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

  4. Incubation of air-pollution-control residues from secondary Pb smelter in deciduous and coniferous organic soil horizons: Leachability of lead, cadmium and zinc

    Energy Technology Data Exchange (ETDEWEB)

    Chrastny, Vladislav, E-mail: vladislavchrastny@seznam.cz [University of South Bohemia, Faculty of Science, Studentska 13, 370 05 Ceske Budejovice (Czech Republic); Czech University of Life Sciences Prague, Faculty of Environmental Sciences, Kamycka 129, 165 21 Prague 6 (Czech Republic); Vanek, Ales [Czech University of Life Sciences Prague, Faculty of Agrobiology, Food and Natural Resources, Kamycka 129, 165 21 Praha 6 (Czech Republic); Komarek, Michael [Czech University of Life Sciences Prague, Faculty of Environmental Sciences, Kamycka 129, 165 21 Prague 6 (Czech Republic); Farkas, Juraj [Czech Geological Survey, Geologicka 6, 152 00 Praha 5 (Czech Republic); Drabek, Ondrej; Vokurkova, Petra [Czech University of Life Sciences Prague, Faculty of Agrobiology, Food and Natural Resources, Kamycka 129, 165 21 Praha 6 (Czech Republic); Nemcova, Jana [University of South Bohemia, Faculty of Agriculture, Studentska 13, 370 05 Ceske Budejovice (Czech Republic)

    2012-03-30

    Highlights: Black-Right-Pointing-Pointer Pb smelter fly ash was incubated in forest soil horizons to assess metal mobility. Black-Right-Pointing-Pointer The metal mobilization depends on pH and the ratio of humic/fulvic acids to SOM. Black-Right-Pointing-Pointer The lowest mobilization of Pb, Zn and Cd took place in horizon H (coniferous forest). Black-Right-Pointing-Pointer A huge amount of Cd was found to have leached in the horizon F (deciduous forest). Black-Right-Pointing-Pointer More vulnerable to metal leaching from APC residues is soil from deciduous forest. - Abstract: The leachability of air-pollution-control (APC) residues from a secondary lead smelter in organic soil horizons (F and H) from a deciduous and a coniferous forest during incubation periods of 0, 3 and 6 months were compared in this work. While the concentration of Pb, Zn and Cd associated with the exchangeable/acid extractable fraction in the horizon F from the coniferous forest was higher compared to the deciduous, significantly lower concentrations in the humified horizon H was found. It is suggested that lower pH and a higher share of fulvic acids fraction (FAs) of solid phase soil organic matter (SOM) in the humified soil horizon H from the coniferous compared to the deciduous forest is responsible for a higher metal association with solid phase SOM and therefore a lower metal leaching in a soil system. From this point of view, the humified soil horizon H from the deciduous forest represents a soil system more vulnerable to Pb, Zn and Cd leaching from APC residues.

  5. 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....

  6. 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.

  7. 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

  8. SELECTIVE FORAGING ON WOODY SPECIES BY THE BEAVER CASTOR FIBER, AND ITS IMPACT ON A RIPARIAN WILLOW FOREST

    NARCIS (Netherlands)

    NOLET, BA; HOEKSTRA, A; OTTENHEIM, MM

    1994-01-01

    Beavers were re-introduced in the Biesbosch, The Netherlands, a wood dominated by willows Salix spp. Conservationists expected that herbivory by beavers would enhance succession to a mixed broad-leaved forest. Willows formed the staple food of the beavers, but they removed only 1.4% of the standing

  9. Litter-dwelling arthropod abundance peaks near coarse woody debris in loblolly pine forest of the southeastern United States.

    Science.gov (United States)

    Michael D. Ulyshen; J.L. Hanula

    2009-01-01

    Several recent studies have shown that many litter-dwelling arthropod and other invertebrate taxa (e.g., Isopoda, Chilopoda, Diplopoda, Araneae, Pseudo scorpionida, Coleoptera, and Gastropoda) are more numerous near dead wood than away from it in the broad-leaved forests of Europe (Jabin et al. 2004; Topp et al. 2006a, 2006b; Kappes et...

  10. Litter-dwelling arthropod abundance peaks near coarse woody debris in loblolly pine forests of the southeastern United States

    Science.gov (United States)

    Michael D. Ulyshen; James L. Hanula

    2009-01-01

    litter-dwelling arthropod and other invertebrate taxa (e.g., Isopoda, Chilopoda, Diplopoda, Araneae, Pseudoscorpionida, Coleoptera, and Gastropoda) are more numerous near dead wood than away from it in the broad-leaved forests of Europe(Jabin et al. 2004; Topp et al. 2006a, 2006b; Kappes et al. 2006; Kappes 2006; Jabin et al. 2007) and...

  11. Modern analogues from the Southern Urals provide insights into biodiversity change in the early Holocene forests of Central Europe

    Czech Academy of Sciences Publication Activity Database

    Chytrý, M.; Danihelka, Jiří; Horsák, M.; Kočí, M.; Kubešová, S.; Lososová, Z.; Otýpková, Z.; Tichý, L.; Martynenko, V. B.; Baisheva, E. Z.

    2010-01-01

    Roč. 37, č. 4 (2010), s. 767-780 ISSN 0305-0270 Institutional research plan: CEZ:AV0Z60050516 Keywords : bryophytes * broad-leaved trees * mixed oak forests Subject RIV: EF - Botanics Impact factor: 4.273, year: 2010

  12. A GENERAL ASSESSMENT OF CLIMATE, SOIL STRUCTURE, FOREST AREAS, GROWING STOCK AND SOME FORESTRY APPLICATIONS OF ARTVIN REGION

    OpenAIRE

    Yüksek, Turan; Ölmez, Zafer

    2011-01-01

    Artvin is located in the North Eastern Blacksea region of Turkey. Forests of Artvin are spread out from cool climate zone to cold climate zone. Artvin has approximately 390471 ha of forests, which is consist of 276883 ha (70.91%) natural forest and 113588 (29.09 %) coppice forests. Forest area covering 54.77% of total land of Artvin. Most of species of forests (natural and coppice forests) areconiferous trees, such as Picea ssp., Pinus ssp., Juniperus ssp. and broaded leaves such as Quercus s...

  13. Creating high-resolution bare-earth digital elevation models (DEMs) from stereo imagery in an area of densely vegetated deciduous forest using combinations of procedures designed for lidar point cloud filtering

    Science.gov (United States)

    DeWitt, Jessica D.; Warner, Timothy A.; Chirico, Peter G.; Bergstresser, Sarah E.

    2017-01-01

    For areas of the world that do not have access to lidar, fine-scale digital elevation models (DEMs) can be photogrammetrically created using globally available high-spatial resolution stereo satellite imagery. The resultant DEM is best termed a digital surface model (DSM) because it includes heights of surface features. In densely vegetated conditions, this inclusion can limit its usefulness in applications requiring a bare-earth DEM. This study explores the use of techniques designed for filtering lidar point clouds to mitigate the elevation artifacts caused by above ground features, within the context of a case study of Prince William Forest Park, Virginia, USA. The influences of land cover and leaf-on vs. leaf-off conditions are investigated, and the accuracy of the raw photogrammetric DSM extracted from leaf-on imagery was between that of a lidar bare-earth DEM and the Shuttle Radar Topography Mission DEM. Although the filtered leaf-on photogrammetric DEM retains some artifacts of the vegetation canopy and may not be useful for some applications, filtering procedures significantly improved the accuracy of the modeled terrain. The accuracy of the DSM extracted in leaf-off conditions was comparable in most areas to the lidar bare-earth DEM and filtering procedures resulted in accuracy comparable of that to the lidar DEM.

  14. OZONE AND SULFUR DIOXIDE DRY DEPOSITION TO FORESTS: OBSERVATIONS AND MODEL EVALUATION

    Science.gov (United States)

    Fluxes and deposition velocities of O3 and SO2 were measured over both a deciduous and a mixed coniferous-deciduous forest for full growing seasons. Fluxes and deposition velocities of O3 were measured over a coniferous forest for a month. Mean deposition velocities of 0.35 t...

  15. [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.

  16. Soil 137Cs activity in a tropical deciduous ecosystem under pasture conversion in Mexico

    International Nuclear Information System (INIS)

    Garcia-Oliva, F.; Maass, J.M.

    1995-01-01

    Soil profiles of 137 Cs were measured in a tropical deciduous ecosystem under pasture conversion on the Pacific Coast of Mexico. Soil samples were taken from unperturbed forest, and from pasture plots following forest conversion. The average total 137 Cs areal activity of non-eroded forest sites indicated a base level of 5 315 ± 427 Bq m -2 . On average, total areal activity on hill-tops was significantly higher (range 10-47%) in the forest than in the pastures. A significant correlation was found between the total 137 Cs areal activity and soil organic matter content (r 2 = 0.16). This correlation can be explained by a soil physical-protection hypothesis. The redistribution of 137 Cs in the landscape is explained by soil erosion processes. (author)

  17. Long and short term changes in the forests of the Cumberland Plateau and Mountains using large scale forest inventory data

    Science.gov (United States)

    Christopher M. Oswalt; Andrew J. Hartsell

    2012-01-01

    The Cumberland Plateau and Mountains (CPM) are a significant component of the eastern deciduous forest with biological and cultural resources strongly connected to and dependent upon the forest resources of the region. As a result, continuous inventory and monitoring is critical. The USDA Forest Service Forest Inventory and Analysis (FIA) program has been collecting...

  18. Variações florística e estrutural e relações fitogeográficas de um fragmento de floresta decídua no Rio Grande do Norte, Brasil Floristic and structural variations, and the phytogeographical relationships of a deciduous forest fragment in Rio Grande do Norte State, Brazil

    Directory of Open Access Journals (Sweden)

    Luiz Antonio Cestaro

    2004-06-01

    nos Cerrados.This work was undertaken in a deciduous forest fragment (~270 ha, centered on 5°53'S and 35°23'W spanning two distinct edaphic environments (Areas 1and 2, and sought to floristically and structurally characterize the tree layers in both environments, as well as to assess their phytogeographical relationships. All living and standing dead trees with CBH >10 cm were sampled using the point-centered quarter method. The results for areas 1and 2 were, respectively: total density, 1.587 and 1.924 individual.ha-1; total basal area, 15.88 and 15.86m².ha-1; most frequent height classes of living trees, 5-5.9m and 6-6.9m; most frequent stem diameters of living trees, 5.09.9cm and 3.2-4.9cm; Shannon diversity index 3.19 and 3.26; and Pielou evenness index, 0.79 and 0.86. The tree layers in both areas 1 and 2 were considered structurally similar. A total of 66 tree species were observed (56 in area 1 and 45 in area 2. Piptadenia moniliformis Benth. showed the greatest importance value in both areas, followed by Tabebuia impetiginosa (Mart. ex DC. Standl. in area 1, and Chamaecrista ensiformis (Vell. H.S. Irwin & Barneby in area 2. Both edaphic environments showed a high floristic similarity (S S = 0.69 and S C = 0.53.Species typical of deciduous forests were more abundant in, or exclusive to, area 1. Species more typical of Caatingas environments were more abundant in, or exclusive to, area 2. The small floristic and structural differences noted between the two areas are apparently attributable to soil conditions. This forest fragment contains many species showing wide distributions in both Neotropical dry forests and Cerrados, and was considered a transitional vegetation type between the Atlantic and Caatingas phytogeographical provinces, in terms of species composition and physiognomy, as well as local environment conditions.

  19. 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.

  20. 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.

  1. Statistical data on forest fund of Russia and changing of forest productivity in the second half of XX century

    Science.gov (United States)

    Alexeyev V.A.; Markov M.V.; R.A. Birdsey; Birdsey R.A.

    2004-01-01

    Contains statistical data on area and growing-stock volume of forest lands in Oblasts, Krays and Republics of Russian Federation, for the period 1961-1998. Positive dynamics of average growing stock for coniferous, deciduous hardwood and deciduous softwood tree stands by stand-age groups were disclosed. The impact of main anthropogenic and natural factors, including...

  2. 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.

  3. Protostelids from deciduous forests: first data from southwestern Europe.

    Science.gov (United States)

    Aguilar, María; Lado, Carlos; Spiegel, Frederick W

    2007-07-01

    The first data of Protostelids from the southwest of Europe are presented in this paper. A total of 21 species were identified from samples collected in Somiedo Biosphere Reserve (Spain). This is the highest species richness recorded to date for Europe or for a latitude this high (>40 degrees ). Seven species (Cavostelium apophysatum, Endostelium zonatum, Microglomus paxillus, Protosporangium fragile, Protostelium okumukumu, Soliformovum expulsum and Schizoplasmodiopsis micropunctata) are new records for Europe. Approximately 65% of the microscopic protostelid species described in the world have been found in this Reserve, a fact that increases the biological value of this protected area and suggests that Spain is an excellent location to study this group. A microhabitat study has been carried out finding differences in species composition and abundance between ground litter, aerial litter, and bark substrates. Comments on the distribution and ecology of the species, as well as illustrations of some species are included.

  4. The Forest, Part 4: Late Summer and Fall

    Science.gov (United States)

    Johnson, Elfriede Nemetz

    1973-01-01

    Briefly describes the ecology of a deciduous forest, and suggests activities for observing and appreciating the changes that occur during the Fall. Simple experiments relating to mosses and lichens are outlined. (JR)

  5. 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

  6. Incubation of air-pollution-control residues from secondary Pb smelter in deciduous and coniferous organic soil horizons: leachability of lead, cadmium and zinc.

    Science.gov (United States)

    Chrastný, Vladislav; Vaněk, Aleš; Komárek, Michael; Farkaš, Juraj; Drábek, Ondřej; Vokurková, Petra; Němcová, Jana

    2012-03-30

    The leachability of air-pollution-control (APC) residues from a secondary lead smelter in organic soil horizons (F and H) from a deciduous and a coniferous forest during incubation periods of 0, 3 and 6 months were compared in this work. While the concentration of Pb, Zn and Cd associated with the exchangeable/acid extractable fraction in the horizon F from the coniferous forest was higher compared to the deciduous, significantly lower concentrations in the humified horizon H was found. It is suggested that lower pH and a higher share of fulvic acids fraction (FAs) of solid phase soil organic matter (SOM) in the humified soil horizon H from the coniferous compared to the deciduous forest is responsible for a higher metal association with solid phase SOM and therefore a lower metal leaching in a soil system. From this point of view, the humified soil horizon H from the deciduous forest represents a soil system more vulnerable to Pb, Zn and Cd leaching from APC residues. Copyright © 2012 Elsevier B.V. All rights reserved.

  7. Boreal forests

    International Nuclear Information System (INIS)

    Essen, P.A.; Ericson, L.; Ehnstroem, B.; Sjoeberg, K.

    1997-01-01

    We review patterns and processes important for biodiversity in the Fennoscandian boreal forest, describe man's past and present impact and outline a strategy for conservation. Natural disturbances, particularly forest fire and gap formation, create much of the structural and functional diversity in forest ecosystems. Several boreal plants and animals are adapted to fire regimes. In contrast, many organisms (epiphytic lichens, fungi, invertebrates) require stable conditions with long continuity in canopy cover. The highly mechanized and efficient Fennoscandian forest industry has developed during the last century. The result is that most natural forest has been lost and that several hundreds of species, mainly cryptograms and invertebrates, are threatened. The forestry is now in a transition from exploitation to sustainable production and has recently incorporated some measures to protect the environment. Programmes for maintaining biodiversity in the boreal forest should include at least three parts. First, the system of forest reserves must be significantly improved through protection of large representative ecosystems and key biotopes that host threatened species. Second, we must restore ecosystem properties that have been lost or altered. Natural disturbance regimes must be allowed to operate or be imitated, for example by artificial fire management. Stand-level management should particularly increase the amount of coarse woody debris, the number of old deciduous trees and large, old conifers, by using partial cutting. Third, natural variation should also be mimicked at the landscape level, for example, by reducing fragmentation and increasing links between landscape elements. Long-term experiments are required to evaluate the success of different management methods in maintaining biodiversity in the boreal forest. (au) 260 refs

  8. 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

  9. The Forest Fire Problem of Degrading Tain II Forest Reserve in Ghana

    African Journals Online (AJOL)

    Agribotix GCS 068

    2010-01-11

    Jan 11, 2010 ... informal practice was done before the 1982/83 dry season when the country ..... Tain II Forest Reserve forms part of the Dry Semi-Deciduous Fire ...... 2003/08; Forest Resources Development Service Working Paper FFM/2. .... Environment, Resources and Development Thailand. web.idrc.ca/uploads/user-.

  10. Stand Structure, Productivity and Carbon Sequestration Potential of Oak Dominated Forests in Kumaun Himalaya

    OpenAIRE

    Bijendra Lal; L.S. Lodhiyal

    2016-01-01

    Present study deals with stand structure, biomass, productivity and carbon sequestration in oak dominated forests mixed with other broad leaved tree species. The sites of studied forests were located in Nainital region between 29058’ N lat. and 79028’ E long at 1500-2150 m elevation. Tree density of forests ranged from 980-1100 ind.ha-1. Of this, oak trees shared 69-97%. The basal area of trees was 31.81 to 63.93 m2 ha-1. R. arboreum and Q. floribunda shared maximum basal area 16.45 and 16.32...

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

    Directory of Open Access Journals (Sweden)

    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

  12. Mapping Deciduous Rubber Plantation Areas and Stand Ages with PALSAR and Landsat Images

    Directory of Open Access Journals (Sweden)

    Weili Kou

    2015-01-01

    Full Text Available Accurate and updated finer resolution maps of rubber plantations and stand ages are needed to understand and assess the impacts of rubber plantations on regional ecosystem processes. This study presented a simple method for mapping rubber plantation areas and their stand ages by integration of PALSAR 50-m mosaic images and multi-temporal Landsat TM/ETM+ images. The L-band PALSAR 50-m mosaic images were used to map forests (including both natural forests and rubber trees and non-forests. For those PALSAR-based forest pixels, we analyzed the multi-temporal Landsat TM/ETM+ images from 2000 to 2009. We first studied phenological signatures of deciduous rubber plantations (defoliation and foliation and natural forests through analysis of surface reflectance, Normal Difference Vegetation Index (NDVI, Enhanced Vegetation Index (EVI, and Land Surface Water Index (LSWI and generated a map of rubber plantations in 2009. We then analyzed phenological signatures of rubber plantations with different stand ages and generated a map, in 2009, of rubber plantation stand ages (≤5, 6–10, >10 years-old based on multi-temporal Landsat images. The resultant maps clearly illustrated how rubber plantations have expanded into the mountains in the study area over the years. The results in this study demonstrate the potential of integrating microwave (e.g., PALSAR and optical remote sensing in the characterization of rubber plantations and their expansion over time.

  13. Potamogeton schweinfurthii and similar broad-leaved species in Italy

    Czech Academy of Sciences Publication Activity Database

    Lastrucci, L.; Frignani, F.; Kaplan, Zdeněk

    2010-01-01

    Roč. 65, č. 1 (2010), s. 147-160 ISSN 0083-7792 R&D Projects: GA ČR GA206/09/0291 Institutional research plan: CEZ:AV0Z60050516 Keywords : Potamogeton * taxonomy * distribution Subject RIV: EF - Botanics

  14. [Temperature sensitivity of soil organic carbon mineralization and β-glucosidase enzymekinetics in the northern temperate forests at different altitudes, China].

    Science.gov (United States)

    Fan, Jin-juan; Li, Dan-dan; Zhang, Xin-yu; He, Nian-peng; Bu, Jin-feng; Wang, Qing; Sun, Xiao-min; Wen, Xue-fa

    2016-01-01

    Soil samples, which were collected from three typical forests, i.e., Betula ermanii forest, coniferous mixed broad-leaved forest, and Pinus koraiensis forest, at different altitudes along the southern slope of Laotuding Mountain of Changbai Mountain range in Liaoning Province of China, were incubated over a temperature gradient in laboratory. Soil organic carbon mineralization rates (Cmin), soil β-1,4-glucosidase (βG) kinetics and their temperature sensitivity (Q₁₀) were measured. The results showed that both altitude and temperature had significant effects on Cmin · Cmin increased with temperature and was highest in the B. ermanii forest. The temperature sensitivity of Cmin [Q₁₀(Cmin)] ranked in order of B. ermanii forest > P. koraiensis forest > coniferous mixed broad-leaved forest, but did not differ significantly among the three forests. Both the maximum activity (Vmax) and the Michaelis constant (Km) of the βG responded positively to temperature for all the forests. The temperature sensitivity of Vmax [Q₁₀(Vmax)] ranged from 1.78 to 1.90, and the temperature sensitivity of Km [Q₁₀(Km)] ranged from 1.79 to 2.00. The Q₁₀(Vmax)/Q10(Km) ratios were significantly greater in the B. ermanii soil than in the other two forest soils, suggesting that the βG kinetics-dependent impacts of the global warming or temperature increase on the decomposition of soil organic carbon were temperature sensitive for the forests at the higher altitudes.

  15. [Organic carbon and carbon mineralization characteristics in nature forestry soil].

    Science.gov (United States)

    Yang, Tian; Dai, Wei; An, Xiao-Juan; Pang, Huan; Zou, Jian-Mei; Zhang, Rui

    2014-03-01

    Through field investigation and indoor analysis, the organic carbon content and organic carbon mineralization characteristics of six kinds of natural forest soil were studied, including the pine forests, evergreen broad-leaved forest, deciduous broad-leaved forest, mixed needle leaf and Korean pine and Chinese pine forest. The results showed that the organic carbon content in the forest soil showed trends of gradual decrease with the increase of soil depth; Double exponential equation fitted well with the organic carbon mineralization process in natural forest soil, accurately reflecting the mineralization reaction characteristics of the natural forest soil. Natural forest soil in each layer had the same mineralization reaction trend, but different intensity. Among them, the reaction intensity in the 0-10 cm soil of the Korean pine forest was the highest, and the intensities of mineralization reaction in its lower layers were also significantly higher than those in the same layers of other natural forest soil; comparison of soil mineralization characteristics of the deciduous broad-leaved forest and coniferous and broad-leaved mixed forest found that the differences of litter species had a relatively strong impact on the active organic carbon content in soil, leading to different characteristics of mineralization reaction.

  16. Simulation of regional temperature change effect of land cover change in agroforestry ecotone of Nenjiang River Basin in China

    Science.gov (United States)

    Liu, Tingxiang; Zhang, Shuwen; Yu, Lingxue; Bu, Kun; Yang, Jiuchun; Chang, Liping

    2017-05-01

    The Northeast China is one of typical regions experiencing intensive human activities within short time worldwide. Particularly, as the significant changes of agriculture land and forest, typical characteristics of pattern and process of agroforestry ecotone change formed in recent decades. The intensive land use change of agroforestry ecotone has made significant change for regional land cover, which had significant impact on the regional climate system elements and the interactions among them. This paper took agroforestry ecotone of Nenjiang River Basin in China as study region and simulated temperature change based on land cover change from 1950s to 1978 and from 1978 to 2010. The analysis of temperature difference sensitivity to land cover change based on Weather Research and Forecasting (WRF) model showed that the land cover change from 1950s to 1978 induced warming effect over all the study area, including the change of grassland to agriculture land, grassland to deciduous broad-leaved forest, and deciduous broad-leaved forest to shrub land. The land cover change from 1978 to 2010 induced cooling effect over all the study area, including the change of deciduous broad-leaved forest to agriculture land, grassland to agriculture land, shrub land to agriculture land, and deciduous broad-leaved forest to grassland. In addition, the warming and cooling effect of land cover change was more significant in the region scale than specific land cover change area.

  17. 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.

  18. Ecology of Missouri Forests. Instructional Unit. Conservation Education Series.

    Science.gov (United States)

    Jackson, Jim

    This unit is designed to help science, social studies, vocational agriculture, and other teachers incorporate forest ecology concepts into their subject matter. The unit includes: (1) topic outline; (2) unit objectives; (3) background information on climate and soils, levels of a deciduous forest, age classes, food and energy relationships, forest…

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

    Science.gov (United States)

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

    2000-01-01

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

  20. 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

  1. Forest Classification Based on Forest texture in Northwest Yunnan Province

    Science.gov (United States)

    Wang, Jinliang; Gao, Yan; Wang, Xiaohua; Fu, Lei

    2014-03-01

    Forest texture is an intrinsic characteristic and an important visual feature of a forest ecological system. Full utilization of forest texture will be a great help in increasing the accuracy of forest classification based on remote sensed data. Taking Shangri-La as a study area, forest classification has been based on the texture. The results show that: (1) From the texture abundance, texture boundary, entropy as well as visual interpretation, the combination of Grayscale-gradient co-occurrence matrix and wavelet transformation is much better than either one of both ways of forest texture information extraction; (2) During the forest texture information extraction, the size of the texture-suitable window determined by the semi-variogram method depends on the forest type (evergreen broadleaf forest is 3×3, deciduous broadleaf forest is 5×5, etc.). (3)While classifying forest based on forest texture information, the texture factor assembly differs among forests: Variance Heterogeneity and Correlation should be selected when the window is between 3×3 and 5×5 Mean, Correlation, and Entropy should be used when the window in the range of 7×7 to 19×19 and Correlation, Second Moment, and Variance should be used when the range is larger than 21×21.

  2. Forest Classification Based on Forest texture in Northwest Yunnan Province

    International Nuclear Information System (INIS)

    Wang, Jinliang; Gao, Yan; Fu, Lei; Wang, Xiaohua

    2014-01-01

    Forest texture is an intrinsic characteristic and an important visual feature of a forest ecological system. Full utilization of forest texture will be a great help in increasing the accuracy of forest classification based on remote sensed data. Taking Shangri-La as a study area, forest classification has been based on the texture. The results show that: (1) From the texture abundance, texture boundary, entropy as well as visual interpretation, the combination of Grayscale-gradient co-occurrence matrix and wavelet transformation is much better than either one of both ways of forest texture information extraction; (2) During the forest texture information extraction, the size of the texture-suitable window determined by the semi-variogram method depends on the forest type (evergreen broadleaf forest is 3×3, deciduous broadleaf forest is 5×5, etc.). (3)While classifying forest based on forest texture information, the texture factor assembly differs among forests: Variance Heterogeneity and Correlation should be selected when the window is between 3×3 and 5×5; Mean, Correlation, and Entropy should be used when the window in the range of 7×7 to 19×19; and Correlation, Second Moment, and Variance should be used when the range is larger than 21×21

  3. Satellite Derived Forest Phenology and Its Relation with Nephropathia Epidemica in Belgium

    Directory of Open Access Journals (Sweden)

    José Miguel Barrios

    2010-06-01

    Full Text Available The connection between nephropathia epidemica (NE and vegetation dynamics has been emphasized in recent studies. Changing climate has been suggested as a triggering factor of recently observed epidemiologic peaks in reported NE cases. We have investigated whether there is a connection between the NE occurrence pattern in Belgium and specific trends in remotely sensed phenology parameters of broad-leaved forests. The analysis of time series of the MODIS Enhanced Vegetation Index revealed that changes in forest phenology, considered in literature as an effect of climate change, may affect the mechanics of NE transmission.

  4. Satellite derived forest phenology and its relation with nephropathia epidemica in Belgium.

    Science.gov (United States)

    Barrios, José Miguel; Verstraeten, Willem W; Maes, Piet; Clement, Jan; Aerts, Jean-Marie; Haredasht, Sara Amirpour; Wambacq, Julie; Lagrou, Katrien; Ducoffre, Geneviève; Van Ranst, Marc; Berckmans, Daniel; Coppin, Pol

    2010-06-01

    The connection between nephropathia epidemica (NE) and vegetation dynamics has been emphasized in recent studies. Changing climate has been suggested as a triggering factor of recently observed epidemiologic peaks in reported NE cases. We have investigated whether there is a connection between the NE occurrence pattern in Belgium and specific trends in remotely sensed phenology parameters of broad-leaved forests. The analysis of time series of the MODIS Enhanced Vegetation Index revealed that changes in forest phenology, considered in literature as an effect of climate change, may affect the mechanics of NE transmission.

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

    Directory of Open Access Journals (Sweden)

    Luciana Mestre

    2017-05-01

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

  6. Characteristics of initial deposition and behavior of radiocesium in forest ecosystems of different locations and species affected by the Fukushima Daiichi Nuclear Power Plant accident

    International Nuclear Information System (INIS)

    Komatsu, Masabumi; Kaneko, Shinji; Ohashi, Shinta; Kuroda, Katsushi; Sano, Tetsuya; Ikeda, Shigeto; Saito, Satoshi; Kiyono, Yoshiyuki; Tonosaki, Mario; Miura, Satoru; Akama, Akio; Kajimoto, Takuya; Takahashi, Masamichi

    2016-01-01

    After the Fukushima Daiichi Nuclear Power Plant (FDNPP) accident, information about stand-level spatial patterns of radiocesium initially deposited in the surrounding forests was essential for predicting the future dynamics of radiocesium and suggesting a management plan for contaminated forests. In the first summer (approximately 6 months after the accident), we separately estimated the amounts of radiocesium ("1"3"4Cs and "1"3"7Cs; Bq m"−"2) in the major components (trees, organic layers, and soils) in forests of three sites with different contamination levels. For a Japanese cedar (Cryptomeria japonica) forest studied at each of the three sites, the radiocesium concentration greatly differed among the components, with the needle and organic layer having the highest concentrations. For these cedar forests, the proportion of the "1"3"7Cs stock in the aboveground tree biomass varied from 22% to 44% of the total "1"3"7Cs stock; it was 44% in highly contaminated sites (7.0 × 10"5 Bq m"−"2) but reduced to 22% in less contaminated sites (1.1 × 10"4 Bq m"−"2). In the intermediate contaminated site (5.0–5.8 × 10"4 Bq m"−"2), 34% of radiocesium was observed in the aboveground tree biomass of the Japanese cedar stand. However, this proportion was considerably smaller (18–19%) in the nearby mixed forests of the Japanese red pine (Pinus densiflora) and deciduous broad-leaved trees. Non-negligible amounts of "1"3"4Cs and "1"3"7Cs were detected in both the sapwood and heartwood of all the studied tree species. This finding suggested that the uptake or translocation of radiocesium had already started within 6 months after the accident. The belowground compartments were mostly present in the organic layer and the uppermost (0–5 cm deep) mineral soil layer at all the study sites. We discussed the initial transfer process of radiocesium deposited in the forest and inferred that the type of initial deposition (i.e., dry versus wet radiocesium deposition

  7. 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

  8. Spatial and temporal trends in distribution of forest fires in Central and Eastern Europe

    Science.gov (United States)

    Ryszard Szczygieł; Barbara Ubysz; Tomasz. Zawiła-Niedźwiecki

    2009-01-01

    Forest in Central and Eastern Europe (CEE) covers 56,285,000 ha (5% of European total forested area). Forest cover in CEE makes 30% of land use. Almost 50% of the forest under study is formed by coniferous species and only 30% by deciduous ones. Forest younger than 60 years old grows on 57% of that area. These factors, together with climate conditions cause that on the...

  9. Association of extinction risk of saproxylic beetles with ecological degradation of forests in Europe.

    Science.gov (United States)

    Seibold, Sebastian; Brandl, Roland; Buse, Jörn; Hothorn, Torsten; Schmidl, Jürgen; Thorn, Simon; Müller, Jörg

    2015-04-01

    To reduce future loss of biodiversity and to allocate conservation funds effectively, the major drivers behind large-scale extinction processes must be identified. A promising approach is to link the red-list status of species and specific traits that connect species of functionally important taxa or guilds to resources they rely on. Such traits can be used to detect the influence of anthropogenic ecosystem changes and conservation efforts on species, which allows for practical recommendations for conservation. We modeled the German Red List categories as an ordinal index of extinction risk of 1025 saproxylic beetles with a proportional-odds linear mixed-effects model for ordered categorical responses. In this model, we estimated fixed effects for intrinsic traits characterizing species biology, required resources, and distribution with phylogenetically correlated random intercepts. The model also allowed predictions of extinction risk for species with no red-list category. Our model revealed a higher extinction risk for lowland and large species as well as for species that rely on wood of large diameter, broad-leaved trees, or open canopy. These results mirror well the ecological degradation of European forests over the last centuries caused by modern forestry, that is the conversion of natural broad-leaved forests to dense conifer-dominated forests and the loss of old growth and dead wood. Therefore, conservation activities aimed at saproxylic beetles in all types of forests in Central and Western Europe should focus on lowlands, and habitat management of forest stands should aim at increasing the amount of dead wood of large diameter, dead wood of broad-leaved trees, and dead wood in sunny areas. © 2014 Society for Conservation Biology.

  10. Water cycle observations in forest watersheds of Cambodia

    Science.gov (United States)

    Shimizu, A.; Tamai, K.; Kabeya, N.; Shimizu, T.; Iida, S. I.

    2015-12-01

    The Lower Mekong River flows through Cambodia, where forests cover ~60% of the country and are believed to have a marked effect on the water cycle. These tropical seasonal forests in the Cambodian flat lands are very precious in the Indochinese Peninsula as few forests of this type remain. However, few hydrological observations have been conducted in these areas. In Cambodia, deciduous and evergreen forests make up 42% and 33% of the total forest area, respectively. We established experimental watersheds both in deciduous and evergreen forests containing meteorological observation towers in Cambodia and collected various observational data since 2003 (O'Krieng, deciduous forest watershed including a 30-m-high observation tower, 2,245 km2; Stung Chinit, evergreen forest watershed including a 60-m-high observation tower, 3,700 km2 including three small watersheds). The basic data from these sites included various kinds of information related to the composition of vegetation, soil characteristics, etc. Hydrologic data was collected and linked to the above data; the main hydrologic research results follow. The water budget for each watershed was determined using an observational rainfall and runoff dataset. The evapotranspiration rate in an evergreen forest was obtained using various observational methods including the Bowen energy-balance ratio and the bandpass eddy covariance method. The annual evapotranspiration of evergreen forests, estimated using the Bowen energy-balance ratio method and water balance, was about 1100-1200 mm, corresponding to 70-80% of annual rainfall. While considering the importance of the presence of evergreen forest, we conducted sap flow measurements to analyze the transpiration process that maintains water uptake through root systems that reach to depths exceeding 8 m. Characteristics of the evaporation from the forest floor that form an important element of the evaporation system were estimated in both evergreen and deciduous forests.

  11. 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.

  12. 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.

  13. 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.

  14. 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…

  15. 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

  16. Estimating wood volume from canopy area in deciduous woodlands ...

    African Journals Online (AJOL)

    In this study we tested the predictive ability of canopy area in estimating wood volume in deciduous woodlands of Zimbabwe. The study was carried out in four sites of different climatic conditions. We used regression analysis to statistically quantify the prediction of wood volume from canopy area at species and stand level ...

  17. ESTIMATION OF CARBON SEQUESTRATION BY RUSSIAN FORESTS: GEOSPATIAL ISSUE

    Directory of Open Access Journals (Sweden)

    N. V. Malysheva

    2017-01-01

    Full Text Available Сategories of carbon sequestration assessment for Russian forests are identified by GIS toolkit. Those are uniform by bioclimatic and site-specific conditions strata corresponding to modern version of bioclimatic forest district division. Stratification of forests at early stage substantially reduces the ambiguity of the evaluation because phytomass conversion sequestration capacity and expansion factor dependent on site-specific condition for calculating of forest carbon sink are absolutely necessary. Forest management units were linked to strata. Biomass conversion and expansion factor for forest carbon sink assessment linked to the strata were recalculated for forest management units. All operations were carried out with GIS analytical toolkit due to accessible functionalities. Units for forest carbon storage inventory and forest carbon balance calculation were localized. Production capacity parameters and forest carbon sequestration capacity have been visualized on maps complied by ArcGIS. Based on spatially-explicit information, we have found out that the greatest annual rates of forest’s carbon accumulation in Russian forests fall into mixed coniferous-deciduous forests of European-Ural part of Russia to Kaliningrad, Smolensk and Briansk Regions, coniferous-deciduous forests close to the boundary of Khabarovsk Region and Primorskij Kray in the Far East, as well as separate forest management units of Kabardino-Balkariya NorthCaucasian mountain area. The geospatial visualization of carbon sequestration by Russian forests and carbon balance assessment has been given.

  18. Environmental measures in forest. Realistic measures for counteracting negative effects of acid precipitation in forest; Miljoetiltak i skog. Realistiske tiltak for aa motvirke negative effekter av sur nedboer i skog

    Energy Technology Data Exchange (ETDEWEB)

    Nilsen, P [Norsk Inst. for Skogforskning, Aas (Norway)

    1996-01-01

    The conference paper deals with an Norwegian research programme concerning environmental measures for decreasing the effects of acidification in forest areas. This programme, which lasts in a period of five years, will terminate in 1997. An important part of the programme has been to investigate other types of measures than the ordinary methods of liming and fertilizing. In the course of the programme, there was determined to put the attention to the increased use of broad-leaved trees as an alternative in a coniferous forest. 19 refs., 1 fig.

  19. 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

  20. 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.

  1. SRTM-DEM and Landsat ETM+ data for mapping tropical dry forest cover and biodiversity assessment in Nicaragua

    Science.gov (United States)

    S.E. Sesnie; S.E. Hagell; S.M. Otterstrom; C.L. Chambers; B.G. Dickson

    2008-01-01

    Tropical dry and deciduous forest comprises as much as 42% of the world’s tropical forests, but has received far less attention than forest in wet tropical areas. Land use change threatens to greatly reduce the extent of dry forest that is known to contain high levels of plant and animal diversity. Forest fragmentation may further endanger arboreal mammals that play...

  2. SRTM-DEM AND LANDSAT ETM+ DATA FOR MAPPING TROPICAL DRY FOREST COVER AND BIODIVERSITY ASSESSMENT IN NICARAGUA

    OpenAIRE

    Brett G. Dickson; Carol L. Chambers; Sarah M. Otterstrom; Suzanne E. Hagell; Steven E. Sesnie

    2008-01-01

    Tropical dry and deciduous forest comprises as much as 42% of the world’s tropical forests, but hasreceived far less attention than forest in wet tropical areas. Land use change threatens to greatly reducethe extent of dry forest that is known to contain high levels of plant and animal diversity. Forest fragmentationmay further endanger arboreal mammals that play principal role in the dispersal of large seeded fruits, plantcommunity assembly and diversity in these systems. Data on the spatial...

  3. Landscape Risk Factors for Lyme Disease in the Eastern Broadleaf Forest Province of the Hudson River Valley and the Effect of Explanatory Data Classification Resolution

    Science.gov (United States)

    This study assessed how landcover classification affects associations between landscape characteristics and Lyme disease rate. Landscape variables were derived from the National Land Cover Database (NLCD), including native classes (e.g., deciduous forest, developed low intensity)...

  4. 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.

  5. 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

  6. [Characteristics of floor litter and soil arthropod community in different types ot subtropical forest in Ailao Mountain of Yunnan, Southwest China].

    Science.gov (United States)

    Yang, Zhao; Yang, Xiao-Dong

    2011-11-01

    By using line transect method, an investigation was conducted on the floor litter and soil arthropod community in a mid mountain wet evergreen broad-leaved forest, a mossy dwarf forest, and a Populus bonatii forest in Ailao Mountain of Yunnan in April (dry and hot season), June (rainy season), and December (dry and cold season), 2005. In both dry and rainy seasons, the existing floor litter mass, C storage, and C/N ratio in the three forests all increased in the order of mossy dwarf forest > P. bonatii forest > evergreen broad-leaved forest, but the N storage had less difference. In the floor litter layer of the forests, Acari and Collembola were the dominant groups of soil arthropod community, while Diptera larvae, Coleoptera, ants, and Homoptera were the common groups. The Sorenson coefficients of soil arthropod community in the three forests were extremely great. No significant differences were observed in the soil arthropod density (ind x m(-2)) in the floor litter layer among the three forests, but the relative density (ind x g(-1)) of soil arthropods was higher in the evergreen broad-leaved forest and P. bonatii forest than in the mossy dwarf forest. In the three forests, the density of soil arthropods was significantly higher in dry season than in rainy season, but the Shannon diversity index had less difference. There were significant positive correlations between the existing floor litter mass and the individual density (ind x m(-2)) and dominant groups of soil arthropod communities in dry and hot season (April), but negative correlations between the existing floor litter mass and the relative density (ind x g(-1)) of soil arthropod communities and Acari in dry and cold season (December). The individual densities of Collembola and Coleoptera also had positive correlations with the N storage of the existing floor litter mass in the three forests. It was considered that the floor litter and the development of soil arthropod community in the litter layer of

  7. Isolation and Culture of Postnatal Stem Cells from Deciduous Teeth

    OpenAIRE

    Olávez, Daniela; Facultad de Odontología Universidad de Los Andes; Salmen, Siham; Instituto de Inmunología Clínica, Universidad de Los Andes.; Padrón, Karla; Facultad de Odontología. Univerisdad de Los Andes.; Lobo, Carmine; Facultad de Odontología. Univerisdad de Los Andes.; Díaz, Nancy; Facultad de Odontología, Universidad de Los Andes.; Berrueta, Lisbeth; Doctora en Inmunología por Instituto Venezolano de Investigaciones Científicas (IVIC). Instituto de Inmunología Clínica, Facultad de Medicina, Universidad de Los Andes, Venezuela.; Solorzanio, Eduvigis; Facultad de Odontología, Universidad de Los Andes.

    2014-01-01

    Background: Currently, degenerative diseases represent a public health problem; therefore, the development and implementation of strategies to fully or partially recover of damaged tissues has a special interest in the biomedical field. Therapeutic strategies based on mesenchymal stem cells transplantation from dental pulp have been proposed as an alternative. Purpose: To develop a mesenchymal stem cells culture isolated from dental pulp of deciduous teeth. Methods: The mesenchymal stem cells...

  8. 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.

  9. 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.

  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. 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

  12. Growth Decline Linked to Warming-Induced Water Limitation in Hemi-Boreal Forests

    OpenAIRE

    Wu, Xiuchen; Liu, Hongyan; Guo, Dali; Anenkhonov, Oleg A.; Badmaeva, Natalya K.; Sandanov, Denis V.

    2012-01-01

    Hemi-boreal forests, which make up the transition from temperate deciduous forests to boreal forests in southern Siberia, have experienced significant warming without any accompanying increase in precipitation during the last 80 years. This climatic change could have a profound impact on tree growth and on the stability of forest ecosystems in this region, but at present evidence for these impacts is lacking. In this study, we report a recent dramatic decline in the growth of hemi-boreal fore...

  13. 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

  14. 长白山阔叶红松林净初级生产力对气候变化的响应:基于BIOME-BGC模型的分析%Response of Broad-Leaved Korean Pine Forest Productivity of Mt.Changbai to Climate Change: An Analysis Based on BIOME-BGC Modeling

    Institute of Scientific and Technical Information of China (English)

    吴玉莲; 王襄平; 李巧燕; 孙阎

    2014-01-01

    为了分析气候变化和大气CO2浓度增加对长白山阔叶红松林净初级生产力(NPP)的影响,运用本地参数化后的BIOME-BGC模型进行模拟,并以实测NPP和增强型植被指数(EVI)进行验证.模拟结果表明,长白山阔叶红松林NPP均值为611.71 gC/(m2·a),1960-2011年年际间的波动范围是473.28~703.44 gC/(m2·a).模拟结果与基于样地实测的NPP(均值为594.66 gC/(m2·a))相似;同时,BIOME-BGC模型模拟的NPP年际间变化趋势与EVI的波动趋势相似,二者间存在显著的相关关系,表明模型能较好地模拟生产力的时间动态.模拟表明,红松的NPP与降水关系更为密切,而阔叶树NPP与温度、降水都呈显著的正相关.模型预测,在未来CO2浓度加倍和温度、降水同时增加的场景下,长白山阔叶红松林NPP将显著增加,其中阔叶树和红松的NPP将分别增加27.87%和23.96%.单独增加温度(2℃)或单独增加降水(12%)都能促进阔叶树和红松NPP的增加,其中降水的作用弱于温度的作用,而单独CO2浓度的倍增对阔叶树和红松的NPP没有明显的影响.

  15. The arboreal component of a dry forest in Northeastern Brazil

    OpenAIRE

    Rodal,M. J. N.; Nascimento,L. M.

    2006-01-01

    The dry forests of northeastern Brazil are found near the coastal zone and on low, isolated mountains inland amid semi-arid vegetation. The floristic composition of these dry montane forests, as well as their relationship to humid forests (Atlantic forest sensu stricto) and to the deciduous thorn woodlands (Caatinga sensu stricto) of the Brazilian northeast are not yet well known. This paper sought to determine if the arboreal plants in a dry forest growing on a low mountain in the semi-arid ...

  16. 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...

  17. 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

  18. Influence of spring phenology on seasonal and annual carbon balance in two contrasting New England forests

    Science.gov (United States)

    Andrew D. Richardson; David Y. Hollinger; D. Bryan Dail; John T. Lee; J. William Munger; John O' Keefe

    2009-01-01

    Spring phenology is thought to exert a major influence on the carbon (C) balance of temperate and boreal ecosystems. We investigated this hypothesis using four spring onset phenological indicators in conjunction with surface-atmosphere CO2 exchange data from the conifer-dominated Howland Forest and deciduous-dominated Harvard Forest AmeriFlux...

  19. Fine Root Growth Phenology, Production, and Turnover in a Northern Hardwood Forest Ecosystem

    Science.gov (United States)

    Dudley J. Raynal

    1994-01-01

    A large part of the nutrient flux in deciduous forests is through fine root turnover, yet this process is seldom measured. As part of a nutrient cycling study, fine root dynamics were studied for two years at Huntington Forest in the Adirondack Mountain region of New York, USA. Root growth phenology was characterized using field rhizotrons, three methods were used to...

  20. Litterfall in the hardwood forest of a minor alluvial-floodplain

    Science.gov (United States)

    Calvin E. Meier; John A. Stanturf; Emile S. Gardiner

    2006-01-01

    within mature deciduous forests, annual development of foliar biomass is a major component of aboveground net primary production and nutrient demand. As litterfall, this same foliage becomes a dominant annual transfer of biomass and nutrients to the detritus pathway. We report litterfall transfers of a mature bottomland hardwood forest in a minor alluvial-floodplain...

  1. Evaluation and prediction of shrub cover in coastal Oregon forests (USA)

    Science.gov (United States)

    Becky K. Kerns; Janet L. Ohmann

    2004-01-01

    We used data from regional forest inventories and research programs, coupled with mapped climatic and topographic information, to explore relationships and develop multiple linear regression (MLR) and regression tree models for total and deciduous shrub cover in the Oregon coastal province. Results from both types of models indicate that forest structure variables were...

  2. 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...

  3. 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.

  4. The arboreal component of a dry forest in Northeastern Brazil

    Directory of Open Access Journals (Sweden)

    M. J. N. Rodal

    Full Text Available The dry forests of northeastern Brazil are found near the coastal zone and on low, isolated mountains inland amid semi-arid vegetation. The floristic composition of these dry montane forests, as well as their relationship to humid forests (Atlantic forest sensu stricto and to the deciduous thorn woodlands (Caatinga sensu stricto of the Brazilian northeast are not yet well known. This paper sought to determine if the arboreal plants in a dry forest growing on a low mountain in the semi-arid inland region (Serra Negra, 8° 35’ - 8° 38’ S and 38° 02’ - 38° 04’ W between the municipalities of Floresta and Inajá, state of Pernambuco have the same floristic composition and structure as that seen in other regional forests. In fifty 10 x 20 m plots all live and standing dead trees with trunk measuring > 5 cm diameter at breast height were measured. Floristic similarities between the forest studied and other regional forests were assessed using multivariate analysis. The results demonstrate that the dry forest studied can be classified into two groups that represent two major vegetational transitions: (1 a humid forest/dry forest transition; and (2 a deciduous thorn-woodland/ dry forest transition.

  5. The arboreal component of a dry forest in Northeastern Brazil.

    Science.gov (United States)

    Rodal, M J N; Nascimento, L M

    2006-05-01

    The dry forests of northeastern Brazil are found near the coastal zone and on low, isolated mountains inland amid semi-arid vegetation. The floristic composition of these dry montane forests, as well as their relationship to humid forests (Atlantic forest sensu stricto) and to the deciduous thorn woodlands (Caatinga sensu stricto) of the Brazilian northeast are not yet well known. This paper sought to determine if the arboreal plants in a dry forest growing on a low mountain in the semi-arid inland region (Serra Negra, 8 degrees 35 - 8 degrees 38 S and 38 degrees 02 - 38 degrees 04 W) between the municipalities of Floresta and Inajá, state of Pernambuco have the same floristic composition and structure as that seen in other regional forests. In fifty 10 x 20 m plots all live and standing dead trees with trunk measuring > 5 cm diameter at breast height were measured. Floristic similarities between the forest studied and other regional forests were assessed using multivariate analysis. The results demonstrate that the dry forest studied can be classified into two groups that represent two major vegetational transitions: (1) a humid forest/dry forest transition; and (2) a deciduous thorn-woodland/ dry forest transition.

  6. 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...

  7. Protecting climate with forests

    Science.gov (United States)

    Jackson, Robert B.; Randerson, James T.; Canadell, Josep G.; Anderson, Ray G.; Avissar, Roni; Baldocchi, Dennis D.; Bonan, Gordon B.; Caldeira, Ken; Diffenbaugh, Noah S.; Field, Christopher B.; Hungate, Bruce A.; Jobbágy, Esteban G.; Kueppers, Lara M.; Nosetto, Marcelo D.; Pataki, Diane E.

    2008-10-01

    Policies for climate mitigation on land rarely acknowledge biophysical factors, such as reflectivity, evaporation, and surface roughness. Yet such factors can alter temperatures much more than carbon sequestration does, and often in a conflicting way. We outline a framework for examining biophysical factors in mitigation policies and provide some best-practice recommendations based on that framework. Tropical projects—avoided deforestation, forest restoration, and afforestation—provide the greatest climate value, because carbon storage and biophysics align to cool the Earth. In contrast, the climate benefits of carbon storage are often counteracted in boreal and other snow-covered regions, where darker trees trap more heat than snow does. Managers can increase the climate benefit of some forest projects by using more reflective and deciduous species and through urban forestry projects that reduce energy use. Ignoring biophysical interactions could result in millions of dollars being invested in some mitigation projects that provide little climate benefit or, worse, are counter-productive.

  8. Protecting climate with forests

    International Nuclear Information System (INIS)

    Jackson, Robert B; Randerson, James T; Anderson, Ray G; Pataki, Diane E; Canadell, Josep G; Avissar, Roni; Baldocchi, Dennis D; Bonan, Gordon B; Caldeira, Ken; Field, Christopher B; Diffenbaugh, Noah S; Hungate, Bruce A; Jobbagy, Esteban G; Nosetto, Marcelo D; Kueppers, Lara M

    2008-01-01

    Policies for climate mitigation on land rarely acknowledge biophysical factors, such as reflectivity, evaporation, and surface roughness. Yet such factors can alter temperatures much more than carbon sequestration does, and often in a conflicting way. We outline a framework for examining biophysical factors in mitigation policies and provide some best-practice recommendations based on that framework. Tropical projects-avoided deforestation, forest restoration, and afforestation-provide the greatest climate value, because carbon storage and biophysics align to cool the Earth. In contrast, the climate benefits of carbon storage are often counteracted in boreal and other snow-covered regions, where darker trees trap more heat than snow does. Managers can increase the climate benefit of some forest projects by using more reflective and deciduous species and through urban forestry projects that reduce energy use. Ignoring biophysical interactions could result in millions of dollars being invested in some mitigation projects that provide little climate benefit or, worse, are counter-productive.

  9. [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.

  10. Diferentes critérios de inclusão amostral e suas interpretações: estudo de caso em floresta estacional decidual Different sizes of the smallest individual sampled and their interpretations: case study in the seasonally dry forest

    Directory of Open Access Journals (Sweden)

    Walnir Gomes Ferreira-Júnior

    2012-12-01

    Full Text Available As florestas estacionais deciduais (FEDs, amplamente distribuídas no Brasil, são formações sujeitas a diferentes métodos de inventários. Consequentemente, os dados gerados podem afetar a comparação com outras formações vegetais. Este estudo apresenta e discute alterações proporcionadas pela amostragem da vegetação utilizando circunferência ao nível do solo (CNS ≥ 10 cm e circunferência à altura do peito (CAP ≥ 15 cm, em fragmentos de FED. O uso de diferentes critérios proporciona uma visão ambígua de um mesmo fragmento florestal, manifestada pelas diferenças em sua estrutura horizontal e riqueza de espécies. The dry forests, widely distributed in Brazil, are formations subject to different sampling method. Consequently, the data generated may affect the comparison among other vegetation formations. Therefore, this study presents and discusses changes caused by sampling vegetation using circumference at soil height (CSH ≥ 10 cm and circumference at breast height (CBH ≥ 15 cm. Different criteria provide an ambiguous vision of a same forest fragment, resulting in different structure and species richness.

  11. Reactive organic air components (C{sub 6}-C{sub 12}) of anthropogenic and biogenic origin in deciduous and coniferous forests. Final report; Reaktive organische Luftkomponenten (C{sub 6}-C{sub 12}) anthropogenen und biogenen Ursprungs in Laub- und Nadelwaeldern. Abschlussbericht

    Energy Technology Data Exchange (ETDEWEB)

    Steinbrecher, R.; Fehsenfeld, U.; Hauff, K.; Jocher, M.; Kolb, C.; Reichmann, A.; Steinbrecher, J.; Tranos, S.; Wiedemann, M.

    1996-08-01

    Biogenic hydrocarbons are known to act as important precursors in tropospheric photochemical ozone formation. Large uncertainties exist about the composition of the mix of volatile organic compounds, emitted by various plant species and the respective emission rates. The emission and deposition behavior of C{sub 6} to C{sub 12} volatile organic compounds (VOC) in Norway spruce forests, oak/pine forests, grassland and the Mediterranean Garigue were studied in detail. The cuvette technique was used to study the emission form the soil, trunks and twigs. The gradient method and the REA-technique were used to obtain canopy fluxes. Among the investigated ecosystems, forests and the Mediterranean Garigue were strong monoterpene emitters, grassland emitted negligible amounts of VOC. Tall forests may act as a sink for anthropogenic hydrocarbons. In a dense Norway spruce forests the contribution of the soil to the total canopy emission was small, the fraction of the steam region may range from 1 to 64% and is not clear yet. For the upper suncrown, with ca. 80% of the needle surfaces the most important source for isoprene and monoterpenes of a closed canopy, a emission factor for {alpha}-pinene of 636 pmol m{sup -2} total needle surface s{sup -1} (30 C leaf temperature and 1000 {mu}E PAR) was calculated. In contrast to the general opinion the main controlling factors of the {alpha}-pinene emission from Norway spruce twigs and the monoterpene emission from Mediterranean oaks are light and temperature. The results of this research were used to update biogenic VOC emission inventories and a significant improvement was achieved. (orig.) [Deutsch] Biogene Kohlenwasserstoffe sind wichtige Vorlaeufer fuer die photochemische Ozonbildung in der Troposphaere. Ueber die qualitative Zusammensetzung der Emissionen von fluechtigen organischen Verbindungen aus der Vegetation und die Quellenstaerken der verschiedenen Verbindungen bestehen grosse Unsicherheiten. In Fichtenwaeldern, Kiefern

  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. FOREST DISTRIBUTION ON THE CENTRAL RUSSIAN UPLAND: HISTORICAL PERSPECTIVE

    Directory of Open Access Journals (Sweden)

    Maria V. Arkhipova

    2014-01-01

    Full Text Available We studied the change of forestland in the Central Russian Upland within the deciduous forest, forest-steppe, and steppe zones using old maps (XVIII-XX cc. and current satellite images. The forest distribution within the Central Russian Upland has been relatively stable during the last 220 years. On average, the decrease in the forested area was small. However, we identified significant changes in certain regions. In the southern part of CRU, the significant increase of the forested land is caused by the forest protection of abatis woodland and afforestation. During the last 100 years, reforestation took place mainly in the Oka basin due to both afforestation and natural reforestation. New forests appeared generally in ravines within all zones. The analysis of the abatis forests changes from the XVIII to XX cc. allowed us to identify forested area within the Central Russian Upland prior to active development.

  14. Problem of industrial fumes in the forested valleys of Savoy

    Energy Technology Data Exchange (ETDEWEB)

    Bossavy, J

    1962-01-01

    A study of injury to forest trees in the Maurienne valley, caused by F in the fumes from aluminum factories was made. Of the local conifers, Pinus sylvestris was the most susceptible, followed by Picea abies and Abies alba; Larch has so far proved resistant, as have broadleaved deciduous species.

  15. Plant functional traits with particular reference to tropical deciduous

    Indian Academy of Sciences (India)

    predict its response as well as its influence on ecosystem functioning. ... can enable prediction of the dynamics of these forests in the face of disturbance and global climate change ...... cloud forest into two functional groups on the basis of SLA,.

  16. Isolation of Mesenchymal Stem Cells from Human Deciduous Teeth Pulp

    Directory of Open Access Journals (Sweden)

    Aileen I. Tsai

    2017-01-01

    Full Text Available This study aimed to identify predictors of success rate of mesenchymal stem cell (MSC isolation from human deciduous teeth pulp. A total of 161 deciduous teeth were extracted at the dental clinic of Chang Gung Memorial Hospital. The MSCs were isolated from dental pulps using a standard protocol. In total, 128 colonies of MSCs were obtained and the success rate was 79.5%. Compared to teeth not yielding MSCs successfully, those successfully yielding MSCs were found to have less severe dental caries (no/mild-to-moderate/severe: 63.3/24.2/12.5% versus 12.5/42.4/42.4%, P<0.001 and less frequent pulpitis (no/yes: 95.3/4.7% versus 51.5/48.5%, P<0.001. In a multivariate regression model, it was confirmed that the absence of dental caries (OR = 4.741, 95% CI = 1.564–14.371, P=0.006 and pulpitis (OR = 9.111, 95% CI = 2.921–28.420, P<0.001 was significant determinants of the successful procurement of MSCs. MSCs derived from pulps with pulpitis expressed longer colony doubling time than pulps without pulpitis. Furthermore, there were higher expressions of proinflammatory cytokines, interleukin- (IL- 6 and monocyte chemoattractant protein- (MCP- 1, P<0.01, and innate immune response [toll-like receptor 1 (TLR1 and TLR8, P<0.05; TLR2, TLR3, and TLR6, P<0.01] in the inflamed than noninflamed pulps. Therefore, a carious deciduous tooth or tooth with pulpitis was relatively unsuitable for MSC processing and isolation.

  17. Bilateral supernumerary teeth in deciduous dentition-a rarity.

    Science.gov (United States)

    Acharya, Sonu; Ghosh, Chiranjit; Mondal, Pradeep Kumar

    2014-05-01

    Supernumerary teeth are considered as one of the most significant dental anomalies during the primary and early mixed dentition stages. They are of great concern to the dentists and parents because of the eruption, occlusal, and esthetic problems they can cause. Supernumerary teeth occur more frequently in the permanent dentition but rarely in primary dentition and more often seen in males. A supernumerary tooth in the primary dentition can cause ectopic or delayed eruption of permanent central incisors which will further alter occlusion and may compromise esthetics and formation of dentigerous cysts. Here we discuss a case of bilateral supernumerary teeth in deciduous dentition in a female child.

  18. Lead levels in deciduous teeth of children in Yemen

    International Nuclear Information System (INIS)

    Ismail, Rokhsana M.

    2001-01-01

    To determine lead exposure among children in Yemen a total of 280 shed deciduous whole teeth were collected from 269 children. Teeth were analyzed for lead concentrations using atomic absorption spectrophotometry (SP9 Philips) with electrothermal atomization. Children were between 5 and 15 years old. The study period extended from April 1999 to August 2000. The study showed that the overall mean tooth - lead level was 2.15 mg/g dry weight with a range of 0.05-30.4 mg/g dry weight. (author)

  19. Forest Dynamics in the Eastern Ghats of Tamil Nadu, India

    Science.gov (United States)

    Jayakumar, S.; Ramachandran, A.; Bhaskaran, G.; Heo, J.

    2009-02-01

    The primary deciduous forests in the Eastern Ghats (EG) of Tamil Nadu (TN) India have undergone many changes owing to various need-based forest managements, such as timber extraction for industry, railway sleepers, charcoal, and forest clearance for hydroelectric projects and agriculture, during preindependence and postindependence periods (i.e., from 1800 to 1980). The enactment of a forest conservation act during the 1980s changed the perception of forest managers from utilization to conservation. This study was taken up to assess the forests dynamics in the EG of TN spatially between 1990 and 2003 and nonspatially between 1900 and the 1980s. Landsat Thematic Mapper (TM) and Indian Remote Sensing satellite (IRS) 1D Linear Imaging and Self Scanning (LISS III) data were used to assess forests during 1990 and 2003, respectively. Field floristic survey and secondary data (such as published literature, floras, books, and forest working plans) were used to assess the forest dynamics in terms of forest type and species composition among the preindependence period, the postindependence period, and the present (i.e., before and after 1980). The satellite data analysis revealed a considerable amount of changes in all forest types during the 13 years. The comparison of species composition and forest types between the past and present revealed that need-based forest management along with anthropogenic activity have altered the primary deciduous forest in to secondary and postextraction secondary forests such as southern thorn and southern thorn scrub forests in the middle [400-900 m above mean sea level (MSL)] and lower slopes (900 m MSL) and plateau seemed not to be much affected by the forest management. The changes estimated by the satellite data processing in the major forest types such as evergreen, deciduous, southern thorn, and southern thorn scrub are really alarming because these changes have occurred after the implementation of a forest conservation act. The

  20. [Characteristics of carbon storage of Inner Mongolia forests: a review].

    Science.gov (United States)

    Yang, Hao; Hu, Zhong-Min; Zhang, Lei-Ming; Li, Sheng-Gong

    2014-11-01

    Forests in Inner Mongolia account for an important part of the forests in China in terms of their large area and high living standing volume. This study reported carbon storage, carbon density, carbon sequestration rate and carbon sequestration potential of forest ecosystems in Inner Mongolia using the biomass carbon data from the related literature. Through analyzing the data of forest inventory and the generalized allometric equations between volume and biomass, previous studies had reported that biomass carbon storage of the forests in Inner Mongolia was about 920 Tg C, which was 12 percent of the national forest carbon storage, the annual average growth rate was about 1.4%, and the average of carbon density was about 43 t · hm(-2). Carbon storage and carbon density showed an increasing trend over time. Coniferous and broad-leaved mixed forest, Pinus sylvestris var. mongolica forest and Betula platyphylla forest had higher carbon sequestration capacities. Carbon storage was reduced due to human activities such as thinning and clear cutting. There were few studies on carbon storage of the forests in Inner Mongolia with focus on the soil, showing that the soil car- bon density increased with the stand age. Study on the carbon sequestration potential of forest ecosystems was still less. Further study was required to examine dynamics of carbon storage in forest ecosystems in Inner Mongolia, i. e., to assess carbon storage in the forest soils together with biomass carbon storage, to compute biomass carbon content of species organs as 45% in the allometric equations, to build more species-specific and site-specific allometric equations including root biomass for different dominant species, and to take into account the effects of climate change on carbon sequestration rate and carbon sequestration potential.

  1. 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.

  2. 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).

  3. Middle paleolithic human deciduous incisor from Grotta del Cavallo, Italy.

    Science.gov (United States)

    Fabbri, Pier Francesco; Panetta, Daniele; Sarti, Lucia; Martini, Fabio; Salvadori, Piero A; Caramella, Davide; Fedi, Mariaelena; Benazzi, Stefano

    2016-11-01

    In this contribution, we present a morphological description and comparative morphometric analysis of Cavallo D, a human tooth unearthed from the Mousterian FIII sublayer of Grotta del Cavallo (Apulia, Italy). We used microCT data to provide a detailed morphological description and morphometric analysis of the Cavallo D human tooth based on traditional diameter measurements and 3D enamel thickness. Moreover, new AMS radiocarbon dating of charcoals from layers FII was carried out. Morphological features observed in Cavallo D align the tooth to Neandertals. Similarly, the large size of the tooth (e.g., BL diameter) and the relatively thinner enamel thickness are typical Neandertal traits. 14 C datings of layer FII attribute the tooth to a time range of 45,600-42,900 cal BP (at 68% level of probability). Up to now, the Rdi 1 Cavallo D represents the most recent Neandertal human remain in southern Italy related to a radiocarbon dated stratigraphy. Moreover, since deciduous teeth have been less investigated than the permanent ones, this contribution brings new data to increase our knowledge on the variability of the Neandertal deciduous dentition. © 2016 Wiley Periodicals, Inc.

  4. Impaired receptivity and decidualization in DHEA-induced PCOS mice.

    Science.gov (United States)

    Li, Shu-Yun; Song, Zhuo; Song, Min-Jie; Qin, Jia-Wen; Zhao, Meng-Long; Yang, Zeng-Ming

    2016-12-07

    Polycystic ovary syndrome (PCOS), a complex endocrine disorder, is a leading cause of female infertility. An obvious reason for infertility in PCOS women is anovulation. However, success rate with high quality embryos selected by assisted reproduction techniques in PCOS patients still remain low with a high rate of early clinical pregnancy loss, suggesting a problem in uterine receptivity. Using a dehydroepiandrosterone-induced mouse model of PCOS, some potential causes of decreased fertility in PCOS patients were explored. In our study, ovulation problem also causes sterility in PCOS mice. After blastocysts from normal mice are transferred into uterine lumen of pseudopregnant PCOS mice, the rate of embryo implantation was reduced. In PCOS mouse uteri, the implantation-related genes are also dysregulated. Additionally, artificial decidualization is severely impaired in PCOS mice. The serum estrogen level is significantly higher in PCOS mice than vehicle control. The high level of estrogen and potentially impaired LIF-STAT3 pathway may lead to embryo implantation failure in PCOS mice. Although there are many studies about effects of PCOS on endometrium, both embryo transfer and artificial decidualization are applied to exclude the effects from ovulation and embryos in our study.

  5. Deciduous shrubs for ozone bioindication: Hibiscus syriacus as an example

    Energy Technology Data Exchange (ETDEWEB)

    Paoletti, Elena [Institut Plant Protection (IPP), National Council Research (CNR), Via Madonna del Piano 10, 50019 Sesto Fiorentino, Florence (Italy)], E-mail: e.paoletti@ipp.cnr.it; Ferrara, Anna Maria [Istituto per le Piante da Legno e l' Ambiente (IPLA), Corso Casale 476, 10132 Turin (Italy); Calatayud, Vicent; Cervero, Julia [Fundacion C.E.A.M., Charles R. Darwin 14, Parc Tecnologic, 46980 Paterna, Valencia (Spain); Giannetti, Fabio [Istituto per le Piante da Legno e l' Ambiente (IPLA), Corso Casale 476, 10132 Turin (Italy); Sanz, Maria Jose [Fundacion C.E.A.M., Charles R. Darwin 14, Parc Tecnologic, 46980 Paterna, Valencia (Spain); Manning, William J. [Department of Plant, Soil and Insect Sciences, University of Massachusetts, Amherst, MA 01003-9320 (United States)

    2009-03-15

    Ozone-like visible injury was detected on Hibiscus syriacus plants used as ornamental hedges. Weekly spray of the antiozonant ethylenediurea (EDU, 300 ppm) confirmed that the injury was induced by ambient ozone. EDU induced a 75% reduction in visible injury. Injury was more severe on the western than on the eastern exposure of the hedge. This factor of variability should be considered in ozone biomonitoring programmes. Seeds were collected and seedlings were artificially exposed to ozone in filtered vs. not-filtered (+30 ppb) Open-Top Chambers. The level of exposure inducing visible injury in the OTC seedlings was lower than that in the ambient-grown hedge. The occurrence of visible injury in the OTC confirmed that the ozone sensitivity was heritable and suggested that symptomatic plants of this deciduous shrub population can be successfully used as ozone bioindicators. EDU is recommended as a simple tool for diagnosing ambient ozone visible injury on field vegetation. - An Italian population of the deciduous shrub Hibiscus syriacus, a common ornamental species in temperate zones, is recommended as ozone bioindicator.

  6. Deciduous shrubs for ozone bioindication: Hibiscus syriacus as an example

    International Nuclear Information System (INIS)

    Paoletti, Elena; Ferrara, Anna Maria; Calatayud, Vicent; Cervero, Julia; Giannetti, Fabio; Sanz, Maria Jose; Manning, William J.

    2009-01-01

    Ozone-like visible injury was detected on Hibiscus syriacus plants used as ornamental hedges. Weekly spray of the antiozonant ethylenediurea (EDU, 300 ppm) confirmed that the injury was induced by ambient ozone. EDU induced a 75% reduction in visible injury. Injury was more severe on the western than on the eastern exposure of the hedge. This factor of variability should be considered in ozone biomonitoring programmes. Seeds were collected and seedlings were artificially exposed to ozone in filtered vs. not-filtered (+30 ppb) Open-Top Chambers. The level of exposure inducing visible injury in the OTC seedlings was lower than that in the ambient-grown hedge. The occurrence of visible injury in the OTC confirmed that the ozone sensitivity was heritable and suggested that symptomatic plants of this deciduous shrub population can be successfully used as ozone bioindicators. EDU is recommended as a simple tool for diagnosing ambient ozone visible injury on field vegetation. - An Italian population of the deciduous shrub Hibiscus syriacus, a common ornamental species in temperate zones, is recommended as ozone bioindicator

  7. 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

  8. Radicular cyst associated with deciduous molar: A report of a case with an unusual radiographic presentation

    Directory of Open Access Journals (Sweden)

    Sulabha A Narsapur

    2012-01-01

    Full Text Available Radicular cysts arising from deciduous teeth are rare. This article presents a case report of a radicular cyst associated with a mandibular deciduous second molar and with unusual radiographic findings. The second premolar was displaced to the lower border of the mandible, below the first premolar. The management comprised enucleation of the cystic sac under local anesthesia.

  9. 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.

  10. 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.

  11. Forest resilience to drought varies across biomes.

    Science.gov (United States)

    Gazol, Antonio; Camarero, Jesus Julio; Vicente-Serrano, Sergio M; Sánchez-Salguero, Raúl; Gutiérrez, Emilia; de Luis, Martin; Sangüesa-Barreda, Gabriel; Novak, Klemen; Rozas, Vicente; Tíscar, Pedro A; Linares, Juan C; Martín-Hernández, Natalia; Martínez Del Castillo, Edurne; Ribas, Montse; García-González, Ignacio; Silla, Fernando; Camisón, Alvaro; Génova, Mar; Olano, José M; Longares, Luis A; Hevia, Andrea; Tomás-Burguera, Miquel; Galván, J Diego

    2018-05-01

    Forecasted increase drought frequency and severity may drive worldwide declines in forest productivity. Species-level responses to a drier world are likely to be influenced by their functional traits. Here, we analyse forest resilience to drought using an extensive network of tree-ring width data and satellite imagery. We compiled proxies of forest growth and productivity (TRWi, absolutely dated ring-width indices; NDVI, Normalized Difference Vegetation Index) for 11 tree species and 502 forests in Spain corresponding to Mediterranean, temperate, and continental biomes. Four different components of forest resilience to drought were calculated based on TRWi and NDVI data before, during, and after four major droughts (1986, 1994-1995, 1999, and 2005), and pointed out that TRWi data were more sensitive metrics of forest resilience to drought than NDVI data. Resilience was related to both drought severity and forest composition. Evergreen gymnosperms dominating semi-arid Mediterranean forests showed the lowest resistance to drought, but higher recovery than deciduous angiosperms dominating humid temperate forests. Moreover, semi-arid gymnosperm forests presented a negative temporal trend in the resistance to drought, but this pattern was absent in continental and temperate forests. Although gymnosperms in dry Mediterranean forests showed a faster recovery after drought, their recovery potential could be constrained if droughts become more frequent. Conversely, angiosperms and gymnosperms inhabiting temperate and continental sites might have problems to recover after more intense droughts since they resist drought but are less able to recover afterwards. © 2018 John Wiley & Sons Ltd.

  12. 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...

  13. 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...

  14. Abundance and population structure of eastern worm snakes in forest stands with various levels of overstory tree retention

    Science.gov (United States)

    Zachary I. Felix; Yong Wang; Callie Jo Schweitzer

    2010-01-01

    In-depth analyses of a species’ response to canopy retention treatments can provide insight into reasons for observed changes in abundance. The eastern worm snake (Carphophis amoenus amoenus Say) is common in many eastern deciduous forests, yet little is known about the ecology of the species in managed forests. We examined the relationship between...

  15. Using Lidar and color infrared imagery to successfully measure stand characteristics on the William B. Bankhead National Forest, Alabama

    Science.gov (United States)

    Jeffrey Stephens; Luben Dimov; Callie Schweitzer; Wubishet Tadesse

    2008-01-01

    Light detection and ranging (Lidar) and color infrared imagery (CIR) were used to quantify forest structure and to distinguish deciduous from coniferous trees for selected stands on the William B. Bankhead National Forest in Alabama. Lidar bare ground and vegetation point clouds were used to determine tree heights and tree locations. Lidar accuracy was assessed by...

  16. 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

  17. Leaching of nitrate from temperate forests - effects of air pollution and forest management

    DEFF Research Database (Denmark)

    Gundersen, Per; Schmidt, Inger Kappel; Raulund-Rasmussen, Karsten

    2006-01-01

    deposition (> 8-10 kg ha(-1) a(-1)). We synthesized the current understanding of factors controlling N leaching in relation to three primary causes of N cycle disruption: (i) Increased N input (air pollution, fertilization, N-2 fixing plants). In European forests, elevated N deposition explains approximately...... half of the variability in N leaching, some of the remaining variability could be explained by differences in N availability or "N status". For coniferous forests, needle N content above 1.4% and (or) forest floor C:N ratio lower than 25 were thresholds for elevated nitrate leaching. At adjacent sites...... conifer forests receive higher N deposition and exhibit higher nitrate loss than deciduous forests; an exception is alder that shows substantial nitrate leaching through N fixation input. Fertilization with N poses limited risk to water quality, when applied to N-limited forests. (ii) Reduced plant uptake...

  18. Neural network modelling of rainfall interception in four different forest stands

    OpenAIRE

    Ibrahim Yurtseven; Mustafa Zengin

    2013-01-01

    The objective of this study is to reveal whether it is possible to predict rainfall, throughfall and stemflow in forest ecosystems with less effort, using several measurements of rainfall interception (hereafter interception) and an artificial neural network based linear regression model (ANN model). To this end, the Kerpe Research Forest in the province of Kocaeli, which houses stands of mixed deciduous-broadleaf forest (Castanea sativa Mill., Fagus orientalis Lipsky, Quercus spp.), black pi...

  19. [Impacts of forest and precipitation on runoff and sediment in Tianshui watershed and GM models].

    Science.gov (United States)

    Ouyang, H

    2000-12-01

    This paper analyzed the impacts of foret stand volume and precipitation on annual erosion modulus, mean sediment, maximum sediment, mean runoff, maximum runoff, minimum runoff, mean water level, maximum water level and minimum water level in Tianshui watershed, and also analyzed the effect of the variation of forest stand volume on monthly mean runoff, minimum runoff and mean water level. The dynamic models of grey system GM(1, N) were constructed to simulate the changes of these hydrological elements. The dynamic GM models on the impact of stand volumes of different forest types(Chinese fir, masson pine and broad-leaved forests) with different age classes(young, middle-aged, mature and over-mature) and that of precipitation on the hydrological elements were also constructed, and their changes with time were analyzed.

  20. Measuring and Modeling the Effects of Alternate Post-Fire Successional Trajectories on Boreal Forest Carbon Dynamics

    Science.gov (United States)

    Loranty, M. M.; Goetz, S. J.; Mack, M. C.; Alexander, H. D.; Beck, P. S.

    2011-12-01

    High latitude ecosystems are experiencing amplified climate warming, and recent evidence suggests concurrent intensification of fire disturbance regimes. In central Alaskan boreal forests, severe burns consume more of the soil organic layer, resulting in increased establishment of deciduous seedlings and altered post-fire stand composition with increased deciduous dominance. Quantifying differences in ecosystem carbon (C) dynamics between forest successional trajectories in response to burn severity is essential for understanding potential changes in regional or global feedbacks between boreal forests and climate. We used the Biome BioGeochemical Cycling model (Biome-BGC) to quantify differences in C stocks and fluxes associated with alternate post-fire successional trajectories related to fire severity. A version of Biome-BGC that allows alternate competing vegetation types was calibrated against a series of aboveground biomass observations from chronosequences of stands with differing post-fire successional trajectories characterized by the proportion of deciduous biomass. The model was able to reproduce observed patterns of biomass accumulation after fire, with stands dominated by deciduous species sequestering more C at a faster rate than stands dominated by conifers. Modeled C fluxes suggest that stands dominated by deciduous species are a stronger sink of atmospheric C soon after disturbance than coniferous stands. These results agree with the few available C flux observations. We use a historic database in conjunction with a map of deciduous canopy cover to explore the consequences of ongoing and potential future changes in the fire regime on central Alaskan C balance.

  1. 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.

  2. 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.

  3. 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.

  4. Soil seed banks along elevational gradients in tropical, subtropical and subalpine forests in Yunnan Province, southwest China

    Directory of Open Access Journals (Sweden)

    Xiaqin Luo

    2017-10-01

    Full Text Available Soil seed banks are a vital part of ecosystems and influence community dynamics and regeneration. Although soil seed banks in different habitats have been reported, how soil seed banks vary with elevational gradients in different climatic zones is still unknown. This paper investigates seed density, species composition and nonconstituent species of forest soil seed banks in Yunnan Province, southwest China. Similarity between the soil seed bank and standing vegetation was also examined. We collected soil samples from sites spanning 12 elevations in tropical rain forests, subtropical evergreen broad-leaved forests and subalpine coniferous forests, and transported them to a glasshouse for germination trials for species identification. The soil seed banks of tropical and subtropical forests had much higher seed densities and species richness than those of subalpine forests. Seeds of woody species dominated the soil seed banks of tropical and subtropical forests, while herbs dominated those of subalpine forests. The nonconstituent species in the soil seed banks were all herbs and were most abundant in tropical forests, followed by subtropical forests but were completely absent from subalpine forests.

  5. 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.

  6. The behavior of 137Cs in the soil-forest plants system

    International Nuclear Information System (INIS)

    Spiridonov, S.; Fesenko, S.; Avila, R.

    1999-01-01

    A model has been developed which simulates the behavior of 137 Cs in forest litter and soil, as well as seasonal and long-term dynamics of 137 CS content in forest plants. The long-term cycles of 137 CS migration are described as an integrated result of multiple annual cycles. The model results demonstrate a satisfactory coincidence with the experimental data. A set of model parameters is provided for each of four different types of forest (coniferous and deciduous forest; automorphic and semi-hydromorphic landscapes). The model allows an evaluation of the effects of countermeasures implemented in the contaminated forest. Refs. 1 (author)

  7. 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...

  8. Effects of Fireplace Use on Forest Vegetation and Amount of Woody Debris in Suburban Forests in Northwestern Switzerland

    Science.gov (United States)

    Hegetschweiler, K. Tessa; van Loon, Nicole; Ryser, Annette; Rusterholz, Hans-Peter; Baur, Bruno

    2009-02-01

    Urban forests are popular recreation areas in Europe. Several of these temperate broad-leaved forests also have a high conservation value due to sustainable management over many centuries. Recreational activities, particularly the use of fireplaces, can cause extensive damage to soil, ground vegetation, shrubs, and trees. Firewood collection depletes woody debris, leading to a loss of habitat for specialized organisms. We examined the effects of fireplace use on forest vegetation and the amount of woody debris by comparing disturbed and control plots in suburban forests in northwestern Switzerland. At frequently used fireplaces, we found reduced species densities in the ground vegetation and shrub layer and changes in plant species composition due to human trampling within an area of 150-200 m2. Picnicking and grilling also reduced the height and changed the age structure of shrubs and young trees. The amount of woody debris was lower in disturbed plots than in control plots. Pieces of wood with a diameter of 0.6-7.6 cm were preferentially collected by fireplace users. The reduction in woody debris volume extended up to a distance of 16 m from the fire ring, covering an area of 800 m2 at each picnic site. In order to preserve the ecological integrity of urban forests and to maintain their attractiveness as important recreation areas, we suggest depositing logging residues to be used as firewood and to restrict visitor movements near picnic sites.

  9. 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...

  10. Decidual vasculopathy in preeclampsia: Lesion characteristics relate to disease severity and perinatal outcome

    NARCIS (Netherlands)

    Stevens, D.U.; Al-Nasiry, S.; Bulten, J.; Spaanderman, M.E.A.

    2013-01-01

    OBJECTIVE: In a proportion of patients with preeclampsia, unremodeled spiral arteries develop additional pathological changes, termed decidual vasculopathy (DV), or acute atherosis. DV has been correlated to adverse clinical outcome and increased placental pathology. However, it was unclear whether

  11. 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.

  12. [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.

  13. 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.

  14. Phenotypic and growth characterization of human mesenchymal stem cells cultured from permanent and deciduous teeth

    Directory of Open Access Journals (Sweden)

    Revathi Shekar

    2012-01-01

    Conclusions: Permanent and deciduous teeth are both viable sources of stem cells. The permanent teeth were easier to culture because of a lower chance of contamination with oral microflora. The growth characteristics of the cells obtained from both these sources were similar. However, there was a difference in the ratio of fibroblastoid cells to epithelioid cells between the cultures obtained from the permanent and deciduous teeth.

  15. 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.

  16. Malignant neoplasms of decidual origin (deciduosarcomas) induced by estrogen-progestin-releasing intravaginal devices in rabbits.

    OpenAIRE

    Zook, B. C.; Spiro, I.; Hertz, R.

    1987-01-01

    A combination of estrogen and levonorgestrel was continuously delivered to 23 adult rabbits for up to 2 years via a Silastic ring device sutured into the vagina. Twenty-one control rabbits were given similar rings devoid of drugs. A marked decidual reaction of the endometrium occurred in 16 of 23 test rabbits. In 14 test rabbits (61%) malignant tumors developed of decidual type cells not heretofore described. The deciduosarcomas were composed of anaplastic cells that invaded the uterine walls...

  17. Atmospheric mercury deposition to forests in the eastern USA

    International Nuclear Information System (INIS)

    Risch, Martin R.; DeWild, John F.; Gay, David A.; Zhang, Leiming; Boyer, Elizabeth W.; Krabbenhoft, David P.

    2017-01-01

    Atmospheric mercury (Hg) deposition to forests is important because half of the land cover in the eastern USA is forest. Mercury was measured in autumn litterfall and weekly precipitation samples at a total of 27 National Atmospheric Deposition Program (NADP) monitoring sites in deciduous and mixed deciduous-coniferous forests in 16 states in the eastern USA during 2007–2014. These simultaneous, uniform, repeated, annual measurements of forest Hg include the broadest area and longest time frame to date. The autumn litterfall-Hg concentrations and litterfall mass at the study sites each year were combined with annual precipitation-Hg data. Rates of litterfall-Hg deposition were higher than or equal to precipitation-Hg deposition rates in 70% of the annual data, which indicates a substantial contribution from litterfall to total atmospheric-Hg deposition. Annual litterfall-Hg deposition in this study had a median of 11.7 μg per square meter per year (μg/m 2 /yr) and ranged from 2.2 to 23.4 μg/m 2 /yr. It closely matched modeled dry-Hg deposition, based on land cover at selected NADP Hg-monitoring sites. Mean annual atmospheric-Hg deposition at forest study sites exhibited a spatial pattern partly explained by statistical differences among five forest-cover types and related to the mapped density of Hg emissions. Forest canopies apparently recorded changes in atmospheric-Hg concentrations over time because litterfall-Hg concentrations decreased year to year and litterfall-Hg concentrations were significantly higher in 2007–2009 than in 2012–2014. These findings reinforce reported decreases in Hg emissions and atmospheric elemental-Hg concentrations during this same time period. Methylmercury (MeHg) was detected in all litterfall samples at all sites, compared with MeHg detections in less than half the precipitation samples at selected sites during the study. These results indicate MeHg in litterfall is a pathway into the terrestrial food web where it can

  18. 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)

  19. Lead levels in deciduous teeth of children in Bahrain.

    Science.gov (United States)

    al-Mahroos, F; al-Saleh, F S

    1997-06-01

    To determine lead exposure among children in Bahrain, a total of 280 shed deciduous whole teeth were collected from 269 children. Teeth were analyzed for lead concentrations using atomic absorption spectrophotometry with electrothermal atomization. Children were between 5 and 15 years old. The study period extended from July 1993 to April 1994. The study showed that the overall mean tooth-lead level was 4.3 micrograms/g dry weight with a range of 0.1-60.8 micrograms/g dry weight. The cumulative frequency distribution revealed that 35% of the teeth had a lead concentration of more than 4 micrograms/g dry weight. The tooth-lead concentrations differed according to the tooth type age. The child's sex, nationality, area of residence and socio-economic status had no impact on tooth-lead level. In conclusion, lead is present in toxic concentrations in 35% of the teeth of the children studied. Urgent measures are needed to eliminate lead from gasoline, paint and other sources in the environment.

  20. 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.

  1. Near-natural forests in southern Sweden. Palaeoecological and silvicultural aspects on nature-based silviculture

    Energy Technology Data Exchange (ETDEWEB)

    Bjoerse, Gisela [Swedish Univ. of Agricultural Sciences, Alnarp (Sweden). Southern Swedish Forest Research Centre

    2000-07-01

    Timber production and protection of biodiversity are two main issues in south Swedish forestry. This thesis explores the possibilities of combining the two issues in a nature-based silviculture. Different branches of science, palaeoecology, silviculture and forest vegetation ecology, were combined to give a multidisciplinary approach to the subject. Mimicking the historical forest composition and processes in the silvicultural measures for the benefit of both biodiversity protection and timber production was identified as one possible way of developing a nature-based silviculture. The long period of human influence on the landscape in southern Sweden has effectively removed all the remnants of natural forest that could have been used as references in the mimicking procedure. Consequently, historical references were searched. A method to describe former forest conditions was developed using palaeoecological data and methods. It was found that the historical deciduous dominance was pronounced. Over 2000 years southern Sweden has been transformed from a deciduous to a coniferous landscape. Human activities were shown to be a major driving force in this change. Several detected historical forest types were possible as references for the mimicking approach, but forest types common in the past and rare today were suggested for maximal efficiency in obtaining high biodiversity. Mixed nemoral deciduous forests were pointed out as a historically widespread forest type with very little resemblance in the present landscape. The small fragments left are important for present biodiversity and from many other aspects. Development of a nature-based silvicultural system for the management of mixed nemoral forest stands based on the theory of mimicking was begun. A silvicultural experiment was established in a near-natural, mixed nemoral forest stand in southern Sweden and the early effects of the silvicultural treatments tested were evaluated with regard to floristic diversity

  2. Effects of elevated nitrogen deposition on soil microbial biomass carbon in major subtropical forests of southern China

    Institute of Scientific and Technical Information of China (English)

    Hui WANG; Jiangming MO; Xiankai LU; Jinghua XUE; Jiong LI; Yunting FANG

    2009-01-01

    The effects of elevated nitrogen deposition on soil microbial biomass carbon (C) and extractable dissolved organic carbon (DOC) in three types of forest of southern China were studied in November, 2004 and June, 2006. Plots were established in a pine forest (PF), a mixed pine and broad-leaved forest (MF) and monsoon evergreen broad-leaved forest (MEBF) in the Dinghushan Nature Reserve. Nitrogen treatments included a control (no N addition), low N (50 kg N/(hm2.a)), medium N (100 kg N/ (hm2. a)) and high N (150 kg N/(hm2. a)). Microbial biomass C and extractable DOC were determined using a chloro-form fumigation-extraction method. Results indicate that microbial biomass C and extractable DOC were higher in June, 2006 than in November, 2004 and higher in the MEBF than in the PF or the MF. The response of soil microbial biomass C and extractable DOC to nitrogen deposition varied depending on the forest type and the level of nitrogen treatment. In the PF or MF forests, no significantly different effects of nitrogen addition were found on soil microbial biomass C and extractable DOC. In the MEBF, however, the soil microbial biomass C generally decreased with increased nitrogen levels and high nitrogen addition significantly reduced soil microbial biomass C. The response of soil extractable DOC to added nitrogen in the MEBF shows the opposite trend to soil microbial biomass C. These results suggest that nitrogen deposition may increase the accumulation of soil organic carbon in the MEBF in the study region.

  3. Actinobacterial community dominated by a distinct clade in acidic soil of a waterlogged deciduous forest

    Czech Academy of Sciences Publication Activity Database

    Kopecký, J.; Kyselková, Martina; Omelka, M.; Čermák, L.; Novotná, J.; Grundmann, G.L.; Moënne-Loccoz, Y.; Ságová-Marečková, M.

    2011-01-01

    Roč. 78, č. 2 (2011), s. 386-394 ISSN 0168-6496 Grant - others:GA AVČR(CZ) IAA603020901; GA ČR(CZ) GPP201/11/P290 Program:IA; GP Institutional research plan: CEZ:AV0Z60660521 Keywords : actinobacterial community * gley soil * soil organic matter Subject RIV: EH - Ecology, Behaviour Impact factor: 3.408, year: 2011

  4. Feeding ecology of sharp-shinned hawks in deciduous and coniferous forests in Colorado

    Science.gov (United States)

    Suzanne M. Joy; Richard T. Reynolds; Richard L. Knight; Richard W. Hoffman

    1994-01-01

    Feeding ecology of 11 Sharp-skinned Hawk (Accipiter striates) pairs nesting in aspen (Populus tremuloides), conifer (Abies, Picea spp.), and mixed aspen-conifer habitats in southwest Colorado was investigated during 1988-1989. Small birds (x-bar = 20.9 g, SE = 0.8 g) and mammals (x-bar = 41.1 g, SE = 3.3 g) comprised 91 and 9% of...

  5. Epiphytic lichen community dynamics in deciduous forests around a phosphorus fertiliser factory in Central Lithuania

    Energy Technology Data Exchange (ETDEWEB)

    Motiejunaite, Jurga [Department of Mycology, Institute of Botany, LT-08406 Vilnius 21 (Lithuania)]. E-mail: mikojm@botanika.lt

    2007-03-15

    The detailed dynamics of epiphytic lichen communities were observed while studying permanent quadrats in the zone of influence of a phosphorus fertiliser factory in central Lithuania. The most significant changes were induced by several factors: changes in macroenvironment (increase of illumination), bark scaling, succession processes, individual growth characteristics of the community members, and influence of fungal infection and invertebrate grazing. None of these changes could be directly linked with air pollution. These observations have shown that in conditions of more or less stable pollution, epiphytic community dynamics should be evaluated with care, the best indicators of the characteristics of the communities being species richness and presence/absence and abundance of indicator (nitrophilous or acidophilous) species. - Biotic factors are important when evaluating dynamics of epiphytic communities in polluted areas.

  6. Seasonal variability of interception evaporation from the canopy of a mixed deciduous forest

    DEFF Research Database (Denmark)

    Herbst, Mathias; Rosier, Paul T.W.; McNeil, David D.

    2008-01-01

    and the different aerodynamic properties of the canopy. Together with the lower average rainfall rate this counterbalanced the reduced storage capacity of the leafless canopy and maintained a relatively high interception loss throughout the year being 29% of the gross rainfall in the leafed period and 20...

  7. Effects of an increase in population of sika deer on beetle communities in deciduous forests

    Directory of Open Access Journals (Sweden)

    Taichi Iida

    2016-10-01

    Full Text Available The overabundance of large herbivores is now recognized as a serious ecological problem. However, the resulting ecological consequences remain poorly understood. The ecological effects of an increase in sika deer, Cervus nippon Temminck (Cervidae, on three insect groups of beetles was investigated: ground beetles (Carabidae, carrion beetles (Silphidae, and dung beetles (Scarabaeidae and Geotrupidae on Nakanoshima Island, Hokkaido, northern Japan. We collected beetles on Nakanoshima Island (experimental site and lakeshore areas (control site and compared the species richness, abundance, diversity index, and community composition of beetles between the sites. Results showed that although both species diversity and abundance of carabid beetles were significantly higher at the lakeshore site, those of dung and carrion beetles were higher at the island site. It was additionally observed that abundance of larger carabid beetles was higher at the lakeshore site, whereas that of small-sized carabid beetles did not differ between the lakeshore and island sites. For dung beetles, abundance of smaller species was higher at the island site, whereas that of large species did not differ between the lakeshore and island sites. Abundance of two body sizes (small and large of carrion beetles were both higher at the island site. Overall, the findings of this study demonstrated that an increase in deer population altered the insect assemblages at an island scale, suggesting further changes in ecosystem functions and services in this region.

  8. Analysis of the variability of some properties of a semi-deciduous forest soil

    International Nuclear Information System (INIS)

    Okae-Anti, D.; Ogoe, J.I.

    2003-05-01

    The formation of soils in any region is influenced by many factors such as the parent materials and the secondary materials derived from them, the vegetation and the history of land use. These factors vary from place to place and they contribute to the spatial variation in properties of the soil. Quantification of the magnitude, location and causes of spatial variability is an essential but insufficient ingredient of soil surveys. We took soil samples from the 0-20 cm depth covering soils in the Asuansi-Akroso-Nta-Ofin compound association (Lixisol, Cambisol and Fluvisol association) at the study site, following the nested balanced hierarchical sampling technique. This covered distances between 100 and 0.80 m. Standard laboratory analyses were performed to quantify the selected properties, namely, pH, organic carbon, total nitrogen, total phosphorus, exchangeable potassium and content of sand, silt and clay. Classical statistics and geostatistical procedures were performed on the data and models fitted to the variability patterns. Physical and the more stable properties such as sand, silt and clay were fitted with spherical variogram models. These models indicate a high level of spatial dependence and therefore such properties may be said to be fairly stable in the field. On the contrary, chemical properties such as exchangeable potassium, were fitted with exponential variogram models, indicating that these properties were less stable and showed dependence over longer distances. The scale of variation of the properties ranged between 35 m - 62 m. The degree of uncertainty associated with time and space can be reduced by improved documentation of field variability using the tools of geostatistics. (author)

  9. Epiphytic lichen community dynamics in deciduous forests around a phosphorus fertiliser factory in Central Lithuania

    International Nuclear Information System (INIS)

    Motiejunaite, Jurga

    2007-01-01

    The detailed dynamics of epiphytic lichen communities were observed while studying permanent quadrats in the zone of influence of a phosphorus fertiliser factory in central Lithuania. The most significant changes were induced by several factors: changes in macroenvironment (increase of illumination), bark scaling, succession processes, individual growth characteristics of the community members, and influence of fungal infection and invertebrate grazing. None of these changes could be directly linked with air pollution. These observations have shown that in conditions of more or less stable pollution, epiphytic community dynamics should be evaluated with care, the best indicators of the characteristics of the communities being species richness and presence/absence and abundance of indicator (nitrophilous or acidophilous) species. - Biotic factors are important when evaluating dynamics of epiphytic communities in polluted areas

  10. Epiphytic lichen community dynamics in deciduous forests around a phosphorus fertiliser factory in Central Lithuania.

    Science.gov (United States)

    Motiejūnaite, Jurga

    2007-03-01

    The detailed dynamics of epiphytic lichen communities were observed while studying permanent quadrats in the zone of influence of a phosphorus fertiliser factory in central Lithuania. The most significant changes were induced by several factors: changes in macroenvironment (increase of illumination), bark scaling, succession processes, individual growth characteristics of the community members, and influence of fungal infection and invertebrate grazing. None of these changes could be directly linked with air pollution. These observations have shown that in conditions of more or less stable pollution, epiphytic community dynamics should be evaluated with care, the best indicators of the characteristics of the communities being species richness and presence/absence and abundance of indicator (nitrophilous or acidophilous) species.

  11. Effects of climate variability and functional changes on carbon cycling in a temperate deciduous forest

    DEFF Research Database (Denmark)

    Wu, Jian

    and the fundamental processes at work in this type of ecosystem. The major objectives of this study were to (1) evaluate to what extent and at what temporal scales, direct climatic variability and functional changes (e.g. changes in the structure or physiological properties) regulate the interannual variability (IAV....... In general, the ECB component datasets were consistent after the cross-checking. This, together with their characterized uncertainties, can be used in model data fusion studies. The sensitivity of the C fluxes to climatic variability was significantly higher at shorter than at longer time scales and changed...... seasonally. At the annual time scale, the IAV in net ecosystem exchange of CO2 (NEE) was mostly determined by changes in the ecosystem functional properties. This indicated that the processes controlling the function change need to be incorporated into the process-based ecosystem models. The process...

  12. Aboriginal uses and management of ethnobotanical species in deciduous forests of Chhattisgarh state in India

    Directory of Open Access Journals (Sweden)

    Kala Chandra

    2009-08-01

    Full Text Available Abstract A study on the native uses of ethnobotanical species was carried out in the south Surguja district of Chhattisgarh state in India with the major objective of identifying different food and medicinal plant species and also to understand their ongoing management and conservation. Through questionnaire and personal interviews, a total of 73 ethnobotanical species used by tribal and non-tribal communities were documented, of these 36 species were used in curing different types of diseases and 22 were used as edible food plants. This rich traditional knowledge of local people has an immense potential for pharmacological studies. The outside forces, at present, were mainly blamed to change the traditional system of harvesting and management of ethnobotanical species. The destructive harvesting practices have damaged the existing populations of many ethnobotanical species viz., Asparagus racemosus, Dioscorea bulbifera, Boswellia serrata, Buchnania lanzan, Sterculia urens and Anogeissus latifolia. The sustainable harvesting and management issues of ethnobotanical species are discussed in view of their conservation and management.

  13. Forest Vegetation with Festuca drymeja in Slovakia – Syntaxonomy and Ecology

    Czech Academy of Sciences Publication Activity Database

    Máliš, František; Jarolímek, I.; Kliment, J.; Slezák, M.

    2013-01-01

    Roč. 53, č. 2 (2013), s. 265-288 ISSN 0079-2047 Institutional support: RVO:67985939 Keywords : Symphyto cordatae-Fagion * Carpathians * temperate deciduous and mixed forests Subject RIV: EF - Botanics Impact factor: 0.388, year: 2013

  14. Growth pf Chinese tallow in a bottomland forest in Southern Mississippi

    Science.gov (United States)

    Nana Tian; Zhaofei Fan

    2015-01-01

    Chinese tallow tree [Triadica sebifera (L.) Small, formerly Sapium sebiferum (L.) Roxb.] is a monoecious and deciduous tree, native to central and southern China. As a nonnative invasive tree species, it has aggressively invaded forestlands in southeastern United States, particularly the low- and bottom-land forests along the coastal region of the Gulf of Mexico. This...

  15. Effects of fire severity on plant nutrient uptake reinforce alternate pathways of succession in boreal forests

    Science.gov (United States)

    A. Shenoy; K. Kielland; J.F. Johnstone

    2013-01-01

    Fire activity in the North American boreal region is projected to increase under a warming climate and trigger changes in vegetation composition. In black spruce forests of interior Alaska, fire severity impacts residual organic layer depth which is strongly linked to the relative dominance of deciduous versus coniferous trees in early succession. These alternate...

  16. The demographics and regeneration dynamic of hickory in second-growth temperate forest

    Science.gov (United States)

    Aaron B. Lefland; Marlyse C. Duguid; Randall S. Morin; Mark S. Ashton

    2018-01-01

    Hickory (Carya spp.) is an economically and ecologically important genus to the eastern deciduous forest of North America. Yet, much of our knowledge about the genus comes from observational and anecdotal studies that examine the genus as a whole, or from research that examines only one species, in only one part of its range. Here, we use data sets...

  17. Nitrogen cycling in a forest stream determined by a 15N tracer addition

    Science.gov (United States)

    Patrick J. Mullholland; Jennifer L. Tank; Diane M. Sanzone; Wilfred M. Wollheim; Bruce J. Peterson; Jackson R. Webster; Judy L. Meyer

    2000-01-01

    Nitrogen uptake and cycling was examined using a six-week tracer addition of 15N-labeled ammonium in early spring in Waer Branch, a first-order deciduous forest stream in eastern Tennessee. Prior to the 15N addition, standing stocks of N were determined for the major biomass compartments. During and after the addition,

  18. Climatic potential productivity and an IRS-1CWiFS image in Natural Park Los Alcornocales. Relationship with the standing forest biomass; Productividad Potencial Climatica y una imagen IRS-1CWiFS en el Parque Natural Los Alcornocales. Relacion con la biomasa forestal real

    Energy Technology Data Exchange (ETDEWEB)

    Cuevas, J. M.; Gonzalez-Alonso, F.; Roldan, A.; Huesca, M.

    2009-07-01

    It is studied the use of the Map of Forest Potential Productivity of Spain as information in base to which classify an Indian IRS-1C WiFS satellite image in Los Alcornocales Natural Park (Andalucia, Spain), a large forest area covered by natural forests of Mediterranean broad-leaved species, mainly cork oak (Quercus suber L.). Grouping the classes of climatic potential productivity of this map were obtained three macro classes that resulted significantly different among them at the 99% confidence level for the visible and the Normalized Difference Vegetation Index (NDVI) of the WiFS image. It was built a classifier using these macro classes of climatic potential productivity as ground truth areas. By maximum likelihood supervised classification of the NDVI were obtained classes who resulted significantly different among them at the 90% confidence level for the basal area from the Second Spanish National Forest Inventory ground plots located in the park. (Author) 60 refs.

  19. Fast changes in seasonal forest communities due to soil moisture increase after damming

    Directory of Open Access Journals (Sweden)

    Vagner Santiago do Vale

    2013-12-01

    Full Text Available Local changes caused by dams can have drastic consequences for ecosystems, not only because they change the water regime but also the modification on lakeshore areas. Thus, this work aimed to determine the changes in soil moisture after damming, to understand the consequences of this modification on the arboreal community of dry forests, some of the most endangered systems on the planet. We studied these changes in soil moisture and the arboreal community in three dry forests in the Araguari River Basin, after two dams construction in 2005 and 2006, and the potential effects on these forests. For this, plots of 20m x10m were distributed close to the impoundment margin and perpendicular to the dam margin in two deciduous dry forests and one semi-deciduous dry forest located in Southeastern Brazil, totaling 3.6ha sampled. Besides, soil analysis were undertaken before and after impoundment at three different depths 0-10, 20-30 and 40-50cm. A tree minimum DBH of 4.77cm community inventory was made before T0 and at two T2 and four T4 years after damming. Annual dynamic rates of all communities were calculated, and statistical tests were used to determine changes in soil moisture and tree communities. The analyses confirmed soil moisture increases in all forests, especially during the dry season and at sites closer to the reservoir; besides, an increase in basal area due to the fast growth of many trees was observed. The highest turnover occurred in the first two years after impoundment, mainly due to the higher tree mortality especially of those closer to the dam margin. All forests showed reductions in dynamic rates for subsequent years T2-T4, indicating that these forests tended to stabilize after a strong initial impact. The modifications were more extensive in the deciduous forests, probably because the dry period resulted more rigorous in these forests when compared to semideciduous forest. The new shorelines created by damming increased soil

  20. Variation of biomass and carbon pools with forest type in temperate forests of Kashmir Himalaya, India.

    Science.gov (United States)

    Dar, Javid Ahmad; Sundarapandian, Somaiah

    2015-02-01

    influenced by vegetation type, stand structure, management history, and altitude. Our results reveal that a higher percentage (63 %) of C is stored in biomass and less in soil in these temperate forests except at the higher elevation broad-leaved BU forest. Results from this study will enhance our ability to evaluate the role of these forests in regional and global C cycles and have great implications for planning strategies for conservation. The study provides important data for developing and validating C cycling models for temperate forests.

  1. Vegetation carbon sequestration in Chinese forests from 2010 to 2050.

    Science.gov (United States)

    He, Nianpeng; Wen, Ding; Zhu, Jianxing; Tang, Xuli; Xu, Li; Zhang, Li; Hu, Huifeng; Huang, Mei; Yu, Guirui

    2017-04-01

    Forests store a large part of the terrestrial vegetation carbon (C) and have high C sequestration potential. Here, we developed a new forest C sequestration (FCS) model based on the secondary succession theory, to estimate vegetation C sequestration capacity in China's forest vegetation. The model used the field measurement data of 3161 forest plots and three future climate scenarios. The results showed that logistic equations provided a good fit for vegetation biomass with forest age in natural and planted forests. The FCS model has been verified with forest biomass data, and model uncertainty is discussed. The increment of vegetation C storage in China's forest vegetation from 2010 to 2050 was estimated as 13.92 Pg C, while the average vegetation C sequestration rate was 0.34 Pg C yr -1 with a 95% confidence interval of 0.28-0.42 Pg C yr -1 , which differed significantly between forest types. The largest contributor to the increment was deciduous broadleaf forest (37.8%), while the smallest was deciduous needleleaf forest (2.7%). The vegetation C sequestration rate might reach its maximum around 2020, although vegetation C storage increases continually. It is estimated that vegetation C sequestration might offset 6-8% of China's future emissions. Furthermore, there was a significant negative relationship between vegetation C sequestration rate and C emission rate in different provinces of China, suggesting that developed provinces might need to compensate for undeveloped provinces through C trade. Our findings will provide valuable guidelines to policymakers for designing afforestation strategies and forest C trade in China. © 2016 John Wiley & Sons Ltd.

  2. Enamel defect of deciduous teeth in small gestational age children

    Directory of Open Access Journals (Sweden)

    Willyanti S Syarif

    2010-06-01

    Full Text Available Background: Enamel defect could be caused by genetic and environmental factors in prenatal period. Meanwhile, prenatal malnutrition could also cause small gestational age (SGA. Small Gestational Age is the term used for a neonatal baby with birthweight below the -2SD normal value or 10th percentile on the intrauterine Lubchenco curve. This condition is due to intra-uterine growth restriction, and eventually ends up with several developmental defects of organs, including teeth. In fact, deciduous tooth development has a critical phase within this development period. Purpose: The aim of this study is not only to find out the incidence of enamel defect in SGA children, but also to know the percentage of SGA risk factor to develop enamel defect. Method: This was a epidemiology research with consecutive admission technique. It consisted of 153 SGA children aged 9–48 months. Next, the Ponderal index was used to assign SGA types, symmetrical or asymmetrical one-in this study 59 and 94 respectively. On the other hand, three hundred and ninety Appropriate for Gestational Age (AGA children aged 4–48 months were also included in the study as a control group. Enamel defect then was determined by intraoral examination, classified into hypoplasia and hypocalcifications. Chi-square test was finally used to determine the relative risk ratio between the SGA and the control AGA children. Result: The result of this research showed that incidence of enamel defect in SGA children was 86.92%, meanwhile, that in AGA children was 23.08%, 66.00% of which were commonly suffered from hypocalcification. With p<0.05 it is also known that SGA children has the risk of enamel defect with hypocalcification, about 79% higher than AGA children. Conclusion: It could be concluded that 79% of SGA children had the risk of deciduous tooth enamel defect with hypocalcification as the most.Latar belakang: Defek email dapat terjadi karena faktor genetik dan lingkungan sistemik yang

  3. 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.

  4. 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.

  5. 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.

  6. 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.

  7. 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.

  8. Molecular characterization of soil bacterial community in a perhumid, low mountain forest.

    Science.gov (United States)

    Lin, Yu-Te; Whitman, William B; Coleman, David C; Chih-Yu, Chiu

    2011-01-01

    Forest disturbance often results in changes in soil properties and microbial communities. In the present study, we characterized a soil bacterial community subjected to disturbance using 16S rRNA gene clone libraries. The community was from a disturbed broad-leaved, low mountain forest ecosystem at Huoshaoliao (HSL) located in northern Taiwan. This locality receives more than 4,000 mm annual precipitation, one of the highest precipitations in Taiwan. Based on the Shannon diversity index, Chao1 estimator, richness and rarefaction curve analysis, the bacterial community in HSL forest soils was more diverse than those previously investigated in natural and disturbed forest soils with colder or less humid weather conditions. Analysis of molecular variance also revealed that the bacterial community in disturbed soils significantly differed from natural forest soils. Most of the abundant operational taxonomic units (OTUs) in the disturbed soil community at HSL were less abundant or absent in other soils. The disturbances influenced the composition of bacterial communities in natural and disturbed forests and increased the diversity of the disturbed forest soil community. Furthermore, the warmer and humid weather conditions could also increase community diversity in HSL soils.

  9. [Decidual natural killer cells in recurrent spontaneous abortions].

    Science.gov (United States)

    Janosević, Dragana Radović; Lilić, Vekoslav; Basić, Hakija; Pavlović, Aleksandra Tubić; Stefanović, Milan; Milosević, Jelena

    2011-01-01

    A repeated or habitual miscarriage (PSP) is defined as three or more consecutive losses of pregnancy. In the first three months of pregnancy, habitual miscarriages occur in about 1% of pregnant women, out of which 50% are of an unknown etiology. It is believed that among them, the greatest number is the consequence of an inadequate alloimmune response of a women to the pregnancy. The endocrine and immune systems are in a close interaction during the implantation and maintaining of pregnancy. This communication is the most obvious on endometrium of pregnancy decidua. The aim of the study was to identify the number and the subpopulation distribution of the decidual NK cells in the decidua by using an immunohistochemical method. The research included a group of 30 women who had had two spontaneous miscarriages consecutively in the first three months of their pregnancy, while the curettage after the third spontaneous abortion was histopathologically and immunohistochemically analyzed. The control group consisted of 20 women without a problematic reproductive anamnesis, who had had their pregnancy terminated for social reasons. The criteria for the eliminating from the research were the diagnosed uterus anomalies, positive screening on thrombophilia, as well as women suffering from diabetes melitus and the ones with the thyroid gland function disorder. The number and the phenotype structure of the uterus NK cells were significantly different between the decidua of a normal pregnancy and that in PSP. In the decidua in PSP, there were much more NK cells with the phenotype of the peripheral circulation CD57 and CD56dim, while in the decidua of the control group the dominant cells were the typical uNK cell subpopulation CD56bright. The above mentioned results show that the disregulation of the immunocompetent cells of the decidua, by creating an inadequate cytokine milieu, is one of the mechanism of rejecting the semiallogeneic blastocyst.

  10. Antimicrobial activity of different filling pastes for deciduous tooth treatment

    Directory of Open Access Journals (Sweden)

    Bruna Feltrin ANTONIAZZI

    2015-01-01

    Full Text Available Guedes-Pinto paste is the filling material most employed in Brazil for endodontic treatment of deciduous teeth; however, the Rifocort® ointment has been removed. Thus, the aim of this study was to investigate the antimicrobial potential of filling pastes, by proposing three new pharmacological associations to replace Rifocort® ointment with drugs of already established antimicrobial power: Nebacetin® ointment, 2% Chlorhexidine Gluconate gel, and Maxitrol® ointment. A paste composed of Iodoform, Rifocort® ointment and Camphorated Paramonochlorophenol (CPC was employed as the gold standard (G1. The other associations were: Iodoform, Nebacetin® ointment and CPC (G2; Iodoform, 2% Chlorhexidine Digluconate gel and CPC (G3; Iodoform, Maxitrol® ointment and CPC (G4. The associations were tested for Staphylococcus aureus (S. aureus, Streptococcus mutans (S. mutans, Streptococcus oralis (S. oralis, Enterococcus faecalis (E. faecalis, Escherichia coli (E. coli, and Bacillus subtilis (B. subtilis, using the methods of dilution on solid medium – orifice agar – and broth dilution. The results were tested using statistical analysis ANOVA and Kruskal-Wallis. They showed that all the pastes had a bacteriostatic effect on all the microorganisms, without any statistically significant difference, compared with G1. S. aureus was statistically significant (multiple comparison test of Tukey, insofar as G2 and G3 presented the worst and the best performance, respectively. All associations were bactericidal for E. coli, S. aureus, S. mutans and S. oralis. Only G3 and G4 were bactericidal for E. faecalis, whereas no product was bactericidal for B. subtilis. Thus, the tested pastes have antimicrobial potential and have proved acceptable for endodontic treatment of primary teeth.

  11. 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

  12. Plot size recommendations for biomass estimation in a midwestern old-growth forest

    Science.gov (United States)

    Martin A. Spetich; George R Parker

    1998-01-01

    The authors examine the relationship between disturbance regime and plot size for woody biomass estimation in a midwestern old-growth deciduous forest from 1926 to 1992. Analysis was done on the core 19.6 ac of a 50.1 ac forest in which every tree 4 in. d.b.h. and greater has been tagged and mapped since 1926. Five windows of time are compared—1926, 1976, 1981, 1986...

  13. Predicting the responses of forest distribution and aboveground biomass to climate change under RCP scenarios in southern China.

    Science.gov (United States)

    Dai, Erfu; Wu, Zhuo; Ge, Quansheng; Xi, Weimin; Wang, Xiaofan

    2016-11-01

    In the past three decades, our global climate has been experiencing unprecedented warming. This warming has and will continue to significantly influence the structure and function of forest ecosystems. While studies have been conducted to explore the possible responses of forest landscapes to future climate change, the representative concentration pathways (RCPs) scenarios under the framework of the Coupled Model Intercomparison Project Phase 5 (CMIP5) have not been widely used in quantitative modeling research of forest landscapes. We used LANDIS-II, a forest dynamic landscape model, coupled with a forest ecosystem process model (PnET-II), to simulate spatial interactions and ecological succession processes under RCP scenarios, RCP2.6, RCP4.5 and RCP8.5, respectively. We also modeled a control scenario of extrapolating current climate conditions to examine changes in distribution and aboveground biomass (AGB) among five different forest types for the period of 2010-2100 in Taihe County in southern China, where subtropical coniferous plantations dominate. The results of the simulation show that climate change will significantly influence forest distribution and AGB. (i) Evergreen broad-leaved forests will expand into Chinese fir and Chinese weeping cypress forests. The area percentages of evergreen broad-leaved forests under RCP2.6, RCP4.5, RCP8.5 and the control scenarios account for 18.25%, 18.71%, 18.85% and 17.46% of total forest area, respectively. (ii) The total AGB under RCP4.5 will reach its highest level by the year 2100. Compared with the control scenarios, the total AGB under RCP2.6, RCP4.5 and RCP8.5 increases by 24.1%, 64.2% and 29.8%, respectively. (iii) The forest total AGB increases rapidly at first and then decreases slowly on the temporal dimension. (iv) Even though the fluctuation patterns of total AGB will remain consistent under various future climatic scenarios, there will be certain responsive differences among various forest types. © 2016

  14. Divergence of dominant factors in soil microbial communities and functions in forest ecosystems along a climatic gradient

    Science.gov (United States)

    Xu, Zhiwei; Yu, Guirui; Zhang, Xinyu; He, Nianpeng; Wang, Qiufeng; Wang, Shengzhong; Xu, Xiaofeng; Wang, Ruili; Zhao, Ning

    2018-03-01

    Soil microorganisms play an important role in regulating nutrient cycling in terrestrial ecosystems. Most of the studies conducted thus far have been confined to a single forest biome or have focused on one or two controlling factors, and few have dealt with the integrated effects of climate, vegetation, and soil substrate availability on soil microbial communities and functions among different forests. In this study, we used phospholipid-derived fatty acid (PLFA) analysis to investigate soil microbial community structure and extracellular enzymatic activities to evaluate the functional potential of soil microbes of different types of forests in three different climatic zones along the north-south transect in eastern China (NSTEC). Both climate and forest type had significant effects on soil enzyme activities and microbial communities with considerable interactive effects. Except for soil acid phosphatase (AP), the other three enzyme activities were much higher in the warm temperate zone than in the temperate and the subtropical climate zones. The soil total PLFAs and bacteria were much higher in the temperate zone than in the warm temperate and the subtropical zones. The soil β-glucosidase (BG) and N-acetylglucosaminidase (NAG) activities were highest in the coniferous forest. Except for the soil fungi and fungi-bacteria (F/B), the different groups of microbial PLFAs were much higher in the conifer broad-leaved mixed forests than in the coniferous forests and the broad-leaved forests. In general, soil enzyme activities and microbial PLFAs were higher in primary forests than in secondary forests in temperate and warm temperate regions. In the subtropical region, soil enzyme activities were lower in the primary forests than in the secondary forests and microbial PLFAs did not differ significantly between primary and secondary forests. Different compositions of the tree species may cause variations in soil microbial communities and enzyme activities. Our results

  15. Net aboveground biomass declines of four major forest types with forest ageing and climate change in western Canada's boreal forests.

    Science.gov (United States)

    Chen, Han Y H; Luo, Yong

    2015-10-01

    Biomass change of the world's forests is critical to the global carbon cycle. Despite storing nearly half of global forest carbon, the boreal biome of diverse forest types and ages is a poorly understood component of the carbon cycle. Using data from 871 permanent plots in the western boreal forest of Canada, we examined net annual aboveground biomass change (ΔAGB) of four major forest types between 1958 and 2011. We found that ΔAGB was higher for deciduous broadleaf (DEC) (1.44 Mg ha(-1)  year(-1) , 95% Bayesian confidence interval (CI), 1.22-1.68) and early-successional coniferous forests (ESC) (1.42, CI, 1.30-1.56) than mixed forests (MIX) (0.80, CI, 0.50-1.11) and late-successional coniferous (LSC) forests (0.62, CI, 0.39-0.88). ΔAGB declined with forest age as well as calendar year. After accounting for the effects of forest age, ΔAGB declined by 0.035, 0.021, 0.032 and 0.069 Mg ha(-1)  year(-1) per calendar year in DEC, ESC, MIX and LSC forests, respectively. The ΔAGB declines resulted from increased tree mortality and reduced growth in all forest types except DEC, in which a large biomass loss from mortality was accompanied with a small increase in growth. With every degree of annual temperature increase, ΔAGB decreased by 1.00, 0.20, 0.55 and 1.07 Mg ha(-1)  year(-1) in DEC, ESC, MIX and LSC forests, respectively. With every cm decrease of annual climatic moisture availability, ΔAGB decreased 0.030, 0.045 and 0.17 Mg ha(-1)  year(-1) in ESC, MIX and LSC forests, but changed little in DEC forests. Our results suggest that persistent warming and decreasing water availability have profound negative effects on forest biomass in the boreal forests of western Canada. Furthermore, our results indicate that forest responses to climate change are strongly dependent on forest composition with late-successional coniferous forests being most vulnerable to climate changes in terms of aboveground biomass. © 2015 John Wiley & Sons Ltd.

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

    OpenAIRE

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

    2002-01-01

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

  17. Dispersal limitation drives successional pathways in Central Siberian forests under current and intensified fire regimes.

    Science.gov (United States)

    Tautenhahn, Susanne; Lichstein, Jeremy W; Jung, Martin; Kattge, Jens; Bohlman, Stephanie A; Heilmeier, Hermann; Prokushkin, Anatoly; Kahl, Anja; Wirth, Christian

    2016-06-01

    Fire is a primary driver of boreal forest dynamics. Intensifying fire regimes due to climate change may cause a shift in boreal forest composition toward reduced dominance of conifers and greater abundance of deciduous hardwoods, with potential biogeochemical and biophysical feedbacks to regional and global climate. This shift has already been observed in some North American boreal forests and has been attributed to changes in site conditions. However, it is unknown if the mechanisms controlling fire-induced changes in deciduous hardwood cover are similar among different boreal forests, which differ in the ecological traits of the dominant tree species. To better understand the consequences of intensifying fire regimes in boreal forests, we studied postfire regeneration in five burns in the Central Siberian dark taiga, a vast but poorly studied boreal region. We combined field measurements, dendrochronological analysis, and seed-source maps derived from high-resolution satellite images to quantify the importance of site conditions (e.g., organic layer depth) vs. seed availability in shaping postfire regeneration. We show that dispersal limitation of evergreen conifers was the main factor determining postfire regeneration composition and density. Site conditions had significant but weaker effects. We used information on postfire regeneration to develop a classification scheme for successional pathways, representing the dominance of deciduous hardwoods vs. evergreen conifers at different successional stages. We estimated the spatial distribution of different successional pathways under alternative fire regime scenarios. Under intensified fire regimes, dispersal limitation of evergreen conifers is predicted to become more severe, primarily due to reduced abundance of surviving seed sources within burned areas. Increased dispersal limitation of evergreen conifers, in turn, is predicted to increase the prevalence of successional pathways dominated by deciduous hardwoods

  18. 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.

  19. Mapping Distinct Forest Types Improves Overall Forest Identification Based on Multi-Spectral Landsat Imagery for Myanmar’s Tanintharyi Region

    Directory of Open Access Journals (Sweden)

    Grant Connette

    2016-10-01

    Full Text Available We investigated the use of multi-spectral Landsat OLI imagery for delineating mangrove, lowland evergreen, upland evergreen and mixed deciduous forest types in Myanmar’s Tanintharyi Region and estimated the extent of degraded forest for each unique forest type. We mapped a total of 16 natural and human land use classes using both a Random Forest algorithm and a multivariate Gaussian model while considering scenarios with all natural forest classes grouped into a single intact or degraded category. Overall, classification accuracy increased for the multivariate Gaussian model with the partitioning of intact and degraded forest into separate forest cover classes but slightly decreased based on the Random Forest classifier. Natural forest cover was estimated to be 80.7% of total area in Tanintharyi. The most prevalent forest types are upland evergreen forest (42.3% of area and lowland evergreen forest (21.6%. However, while just 27.1% of upland evergreen forest was classified as degraded (on the basis of canopy cover <80%, 66.0% of mangrove forest and 47.5% of the region’s biologically-rich lowland evergreen forest were classified as degraded. This information on the current status of Tanintharyi’s unique forest ecosystems and patterns of human land use is critical to effective conservation strategies and land-use planning.

  20. MODIS Based Estimation of Forest Aboveground Biomass in China

    Science.gov (United States)

    Sun, Yan; Wang, Tao; Zeng, Zhenzhong; Piao, Shilong

    2015-01-01

    Accurate estimation of forest biomass C stock is essential to understand carbon cycles. However, current estimates of Chinese forest biomass are mostly based on inventory-based timber volumes and empirical conversion factors at the provincial scale, which could introduce large uncertainties in forest biomass estimation. Here we provide a data-driven estimate of Chinese forest aboveground biomass from 2001 to 2013 at a spatial resolution of 1 km by integrating a recently reviewed plot-level ground-measured forest aboveground biomass database with geospatial information from 1-km Moderate-Resolution Imaging Spectroradiometer (MODIS) dataset in a machine learning algorithm (the model tree ensemble, MTE). We show that Chinese forest aboveground biomass is 8.56 Pg C, which is mainly contributed by evergreen needle-leaf forests and deciduous broadleaf forests. The mean forest aboveground biomass density is 56.1 Mg C ha−1, with high values observed in temperate humid regions. The responses of forest aboveground biomass density to mean annual temperature are closely tied to water conditions; that is, negative responses dominate regions with mean annual precipitation less than 1300 mm y−1 and positive responses prevail in regions with mean annual precipitation higher than 2800 mm y−1. During the 2000s, the forests in China sequestered C by 61.9 Tg C y−1, and this C sink is mainly distributed in north China and may be attributed to warming climate, rising CO2 concentration, N deposition, and growth of young forests. PMID:26115195

  1. MODIS Based Estimation of Forest Aboveground Biomass in China.

    Science.gov (United States)

    Yin, Guodong; Zhang, Yuan; Sun, Yan; Wang, Tao; Zeng, Zhenzhong; Piao, Shilong

    2015-01-01

    Accurate estimation of forest biomass C stock is essential to understand carbon cycles. However, current estimates of Chinese forest biomass are mostly based on inventory-based timber volumes and empirical conversion factors at the provincial scale, which could introduce large uncertainties in forest biomass estimation. Here we provide a data-driven estimate of Chinese forest aboveground biomass from 2001 to 2013 at a spatial resolution of 1 km by integrating a recently reviewed plot-level ground-measured forest aboveground biomass database with geospatial information from 1-km Moderate-Resolution Imaging Spectroradiometer (MODIS) dataset in a machine learning algorithm (the model tree ensemble, MTE). We show that Chinese forest aboveground biomass is 8.56 Pg C, which is mainly contributed by evergreen needle-leaf forests and deciduous broadleaf forests. The mean forest aboveground biomass density is 56.1 Mg C ha-1, with high values observed in temperate humid regions. The responses of forest aboveground biomass density to mean annual temperature are closely tied to water conditions; that is, negative responses dominate regions with mean annual precipitation less than 1300 mm y-1 and positive responses prevail in regions with mean annual precipitation higher than 2800 mm y-1. During the 2000s, the forests in China sequestered C by 61.9 Tg C y-1, and this C sink is mainly distributed in north China and may be attributed to warming climate, rising CO2 concentration, N deposition, and growth of young forests.

  2. MODIS Based Estimation of Forest Aboveground Biomass in China.

    Directory of Open Access Journals (Sweden)

    Guodong Yin

    Full Text Available Accurate estimation of forest biomass C stock is essential to understand carbon cycles. However, current estimates of Chinese forest biomass are mostly based on inventory-based timber volumes and empirical conversion factors at the provincial scale, which could introduce large uncertainties in forest biomass estimation. Here we provide a data-driven estimate of Chinese forest aboveground biomass from 2001 to 2013 at a spatial resolution of 1 km by integrating a recently reviewed plot-level ground-measured forest aboveground biomass database with geospatial information from 1-km Moderate-Resolution Imaging Spectroradiometer (MODIS dataset in a machine learning algorithm (the model tree ensemble, MTE. We show that Chinese forest aboveground biomass is 8.56 Pg C, which is mainly contributed by evergreen needle-leaf forests and deciduous broadleaf forests. The mean forest aboveground biomass density is 56.1 Mg C ha-1, with high values observed in temperate humid regions. The responses of forest aboveground biomass density to mean annual temperature are closely tied to water conditions; that is, negative responses dominate regions with mean annual precipitation less than 1300 mm y-1 and positive responses prevail in regions with mean annual precipitation higher than 2800 mm y-1. During the 2000s, the forests in China sequestered C by 61.9 Tg C y-1, and this C sink is mainly distributed in north China and may be attributed to warming climate, rising CO2 concentration, N deposition, and growth of young forests.

  3. Influence of different forest system management practices on leaf litter decomposition rates, nutrient dynamics and the activity of ligninolytic enzymes: a case study from central European forests.

    Science.gov (United States)

    Purahong, Witoon; Kapturska, Danuta; Pecyna, Marek J; Schulz, Elke; Schloter, Michael; Buscot, François; Hofrichter, Martin; Krüger, Dirk

    2014-01-01

    Leaf litter decomposition is the key ecological process that determines the sustainability of managed forest ecosystems, however very few studies hitherto have investigated this process with respect to silvicultural management practices. The aims of the present study were to investigate the effects of forest management practices on leaf litter decomposition rates, nutrient dynamics (C, N, Mg, K, Ca, P) and the activity of ligninolytic enzymes. We approached these questions using a 473 day long litterbag experiment. We found that age-class beech and spruce forests (high forest management intensity) had significantly higher decomposition rates and nutrient release (most nutrients) than unmanaged deciduous forest reserves (Pforest management (low forest management intensity) exhibited no significant differences in litter decomposition rate, C release, lignin decomposition, and C/N, lignin/N and ligninolytic enzyme patterns compared to the unmanaged deciduous forest reserves, but most nutrient dynamics examined in this study were significantly faster under such near-to-nature forest management practices. Analyzing the activities of ligninolytic enzymes provided evidence that different forest system management practices affect litter decomposition by changing microbial enzyme activities, at least over the investigated time frame of 473 days (laccase, Pforest system management practices can significantly affect important ecological processes and services such as decomposition and nutrient cycling.

  4. Isotopic study of the comparative uptake and release of ions by deciduous and permanent dental enamel

    International Nuclear Information System (INIS)

    Tetteh, G.K.

    1975-01-01

    A comparative study of the uptake and release of calcium, orthophosphate, strontium and sodium from decidus and permanent dental enamel has been made using radioactive techniques. The rates of uptake and release of orthophosphate, strontium and sodium were observed to be greater in deciduous than in permanent enamel. However, for calcium, the rate of uptake was observed to be greater in the deciduous than in the permanent enamel but the rate of release was observed to be smaller in the deciduous enamel. These results in conjunction with the findings of Tetteh (1974) suggest that most of the calcification in the early stages of development of dental enamel is by a hetero-ionic exchange. (author) [fr

  5. PCR-based identification of selected pathogens associated with endodontic infections in deciduous and permanent teeth.

    Science.gov (United States)

    Cogulu, Dilsah; Uzel, Atac; Oncag, Ozant; Eronat, Cemal

    2008-09-01

    The aim of the present study was to evaluate the presence of the selected pathogens in samples from deciduous and permanent tooth root canals by using PCR method and to determine the association of these organisms with clinical symptoms. A total of 145 children, 5 to 13 years old, were involved in this study. The presence of selected pathogens (Actinomyces israelii, Candida albicans, Enterococcus faecalis, Fusobacterium nucleatum, Porphyromonas endodontalis, Porphyromonas gingivalis, Prevotella intermedia, Streptococcus intermedius, Treponema denticola, Parvimonas micra, Tannerella forsythensis, Enterococcus faecium, Prevotella melaninogenica) in infected root canals was studied using PCR. T. denticola (P = .012, .02) and E. faecalis (P = .012, .04) were highly associated with periapical radiolucency and previous pain, while P. gingivalis was associated with tenderness to percussion in both deciduous and permanent teeth (P = .01, .015). The results of the present study confirm that certain species of microorganisms are associated with clinical signs and symptoms of endodontic disease in both deciduous and permanent teeth.

  6. Isotopic study of the comparative uptake and release of ions by deciduous and permanent dental enamel

    Energy Technology Data Exchange (ETDEWEB)

    Tetteh, G K [Department of Physics, University of Ghana,Legon

    1975-04-01

    A comparative study of the uptake and release of calcium, orthophosphate, strontium and sodium from decidus and permanent dental enamel has been made using radioactive techniques. The rates of uptake and release of orthophosphate, strontium and sodium were observed to be greater in deciduous than in permanent enamel. However, for calcium, the rate of uptake was observed to be greater in the deciduous than in the permanent enamel but the rate of release was observed to be smaller in the deciduous enamel. These results in conjunction with the findings of Tetteh (1974) suggest that most of the calcification in the early stages of development of dental enamel is by a hetero-ionic exchange.

  7. The role of novel forest ecosystems in the conservation of wood-inhabiting fungi in boreal broadleaved forests.

    Science.gov (United States)

    Juutilainen, Katja; Mönkkönen, Mikko; Kotiranta, Heikki; Halme, Panu

    2016-10-01

    The increasing human impact on the earth's biosphere is inflicting changes at all spatial scales. As well as deterioration and fragmentation of natural biological systems, these changes also led to other, unprecedented effects and emergence of novel habitats. In boreal zone, intensive forest management has negatively impacted a multitude of deadwood-associated species. This is especially alarming given the important role wood-inhabiting fungi have in the natural decay processes. In the boreal zone, natural broad-leaved-dominated, herb-rich forests are threatened habitats which have high wood-inhabiting fungal species richness. Fungal diversity in other broadleaved forest habitat types is poorly known. Traditional wood pastures and man-made afforested fields are novel habitats that could potentially be important for wood-inhabiting fungi. This study compares species richness and fungal community composition across the aforementioned habitat types, based on data collected for wood-inhabiting fungi occupying all deadwood diameter fractions. Corticioid and polyporoid fungi were surveyed from 67 130 deadwood particles in four natural herb-rich forests, four birch-dominated wood pastures, and four birch-dominated afforested field sites in central Finland. As predicted, natural herb-rich forests were the most species-rich habitat. However, afforested fields also had considerably higher overall species richness than wood pastures. Many rare or rarely collected species were detected in each forest type. Finally, fungal community composition showed some divergence not only among the different habitat types, but also among deadwood diameter fractions. Synthesis and applications : In order to maintain biodiversity at both local and regional scales, conserving threatened natural habitat types and managing traditional landscapes is essential. Man-made secondary woody habitats could provide the necessary resources and serve as surrogate habitats for many broadleaved deadwood

  8. Climate change implications of shifting forest management strategy in a boreal forest ecosystem of Norway.

    Science.gov (United States)

    Bright, Ryan M; Antón-Fernández, Clara; Astrup, Rasmus; Cherubini, Francesco; Kvalevåg, Maria; Strømman, Anders H

    2014-02-01

    Empirical models alongside remotely sensed and station measured meteorological observations are employed to investigate both the local and global direct climate change impacts of alternative forest management strategies within a boreal ecosystem of eastern Norway. Stand-level analysis is firstly executed to attribute differences in daily, seasonal, and annual mean surface temperatures to differences in surface intrinsic biophysical properties across conifer, deciduous, and clear-cut sites. Relative to a conifer site, a slight local cooling of −0.13 °C at a deciduous site and −0.25 °C at a clear-cut site were observed over a 6-year period, which were mostly attributed to a higher albedo throughout the year. When monthly mean albedo trajectories over the entire managed forest landscape were taken into consideration, we found that strategies promoting natural regeneration of coniferous sites with native deciduous species led to substantial global direct climate cooling benefits relative to those maintaining current silviculture regimes – despite predicted long-term regional warming feedbacks and a reduced albedo in spring and autumn months. The magnitude and duration of the cooling benefit depended largely on whether management strategies jointly promoted an enhanced material supply over business-as-usual levels. Expressed in terms of an equivalent CO2 emission pulse at the start of the simulation, the net climate response at the end of the 21st century spanned −8 to −159 Tg-CO2-eq., depending on whether near-term harvest levels increased or followed current trends, respectively. This magnitude equates to approximately −20 to −300% of Norway's annual domestic (production) emission impact. Our analysis supports the assertion that a carbon-only focus in the design and implementation of forest management policy in boreal and other climatically similar regions can be counterproductive – and at best – suboptimal if boreal forests are to be used as a

  9. Hawkmoth fauna (Sphingidae, Lepidoptera in a semi-deciduous rainforest remnant: composition, temporal fluctuations, and new records for northeastern Brazil

    Directory of Open Access Journals (Sweden)

    LUIS M. PRIMO

    2013-09-01

    Full Text Available We carried out a qualitative and quantitative inventory of the hawkmoth fauna (Sphingidae of an area of semi-deciduous seasonal rainforest in the state of Pernambuco (Tapacurá Ecological Station, northeastern Brazil. Hawkmoths were sampled monthly from October 2004 to February 2007 (27 months. We recorded 31 species from 16 genera, three tribes, and three families. Macroglossinae was the most abundant subfamily and represented ca. 71% of all species. Out of the 277 individuals collected, 88.4% were males. Five new records were made for northeastern Brazil: Enyo gorgon (Cramer, 1777, Perigonia stulta (Herrich-Schäffer, [1854], Eupyrrhoglossum sagra (Poey, 1832, Nyceryx coffaeae (Walker, 1856 and Xylophanes chiron (Drury, 1773. Eight further species were recorded for the first time for the Pernambuco Endemism Center, showing the important role played by Tapacurá Station in preserving the biodiversity of this insect group. Species richness and abundance were directly related to rainfall: about 70% of all individuals were captured during the rainy season. Changes in Sphingidae populations may, however, be caused by other factors that directly affect either larvae and adults of those insects, such as matrix effect and forest fragment size, which influence migration processes and the presence of predators.

  10. 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.

  11. 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

  12. Urban Forests

    Science.gov (United States)

    David Nowak

    2016-01-01

    Urban forests (and trees) constitute the second forest resource considered in this report. We specifically emphasize the fact that agricultural and urban forests exist on a continuum defined by their relationship (and interrelationship) with a given landscape. These two forest types generally serve different purposes, however. Whereas agricultural forests are...

  13. Particle fluxes above forests: Observations, methodological considerations and method comparisons

    International Nuclear Information System (INIS)

    Pryor, S.C.; Larsen, S.E.; Sorensen, L.L.; Barthelmie, R.J.

    2008-01-01

    This paper reports a study designed to test, evaluate and compare micro-meteorological methods for determining the particle number flux above forest canopies. Half-hour average particle number fluxes above a representative broad-leaved forest in Denmark derived using eddy covariance range from -7 x 10 7 m -2 s -1 (1st percentile) to 5 x 10 7 m -2 s -1 (99th percentile), and have a median value of -1.6 x 10 6 m -2 s -1 . The statistical uncertainties associated with the particle number flux estimates are larger than those for momentum fluxes and imply that in this data set approximately half of the particle number fluxes are not statistically different to zero. Particle number fluxes from relaxed eddy accumulation (REA) and eddy covariance are highly correlated and of almost identical magnitude. Flux estimates from the co-spectral and dissipation methods are also correlated with those from eddy covariance but exhibit higher absolute magnitude of fluxes. - Number fluxes of ultra-fine particles over a forest computed using four micro-meteorological techniques are highly correlated but vary in magnitude

  14. [Effects of forest regeneration patterns on the quantity and chemical structure of soil solution dissolved organic matter in a subtropical forest.

    Science.gov (United States)

    Yuan, Xiao Chun; Lin, Wei Sheng; Pu, Xiao Ting; Yang, Zhi Rong; Zheng, Wei; Chen, Yue Min; Yang, Yu Sheng

    2016-06-01

    Using the negative pressure sampling method, the concentrations and spectral characte-ristics of dissolved organic matter (DOM) of soil solution were studied at 0-15, 15-30, 30-60 cm layers in Castanopsis carlesii forest (BF), human-assisted naturally regenerated C. carlesii forest (RF), C. carlesii plantation (CP) in evergreen broad-leaved forests in Sanming City, Fujian Pro-vince. The results showed that the overall trend of dissolved organic carbon (DOC) concentrations in soil solution was RF>CP>BF, and the concentration of dissolved organic nitrogen (DON) was highest in C. carlesii plantation. The concentrations of DOC and DON in surface soil (0-15 cm) were all significantly higher than in the subsurface (30-60 cm). The aromatic index (AI) was in the order of RF>CP>BF, and as a whole, the highest AI was observed in the surface soil. Higher fluorescence intensity and a short wave absorption peak (320 nm) were observed in C. carlesii plantation, suggesting the surface soil of C. carlesii plantation was rich in decomposed substance content, while the degree of humification was lower. A medium wave absorption peak (380 nm) was observed in human-assisted naturally regenerated C. carlesii forest, indicating the degree of humification was higher which would contribute to the storage of soil fertility. In addition, DOM characte-ristics in 30-60 cm soil solution were almost unaffected by forest regeneration patterns.

  15. Forest Ecosystem Dynamics Assessment and Predictive Modelling in Eastern Himalaya

    Science.gov (United States)

    Kushwaha, S. P. S.; Nandy, S.; Ahmad, M.; Agarwal, R.

    2011-09-01

    This study focused on the forest ecosystem dynamics assessment and predictive modelling deforestation and forest cover prediction in a part of north-eastern India i.e. forest areas along West Bengal, Bhutan, Arunachal Pradesh and Assam border in Eastern Himalaya using temporal satellite imagery of 1975, 1990 and 2009 and predicted forest cover for the period 2028 using Cellular Automata Markov Modedel (CAMM). The exercise highlighted large-scale deforestation in the study area during 1975-1990 as well as 1990-2009 forest cover vectors. A net loss of 2,334.28 km2 forest cover was noticed between 1975 and 2009, and with current rate of deforestation, a forest area of 4,563.34 km2 will be lost by 2028. The annual rate of deforestation worked out to be 0.35 and 0.78% during 1975-1990 and 1990-2009 respectively. Bamboo forest increased by 24.98% between 1975 and 2009 due to opening up of the forests. Forests in Kokrajhar, Barpeta, Darrang, Sonitpur, and Dhemaji districts in Assam were noticed to be worst-affected while Lower Subansiri, West and East Siang, Dibang Valley, Lohit and Changlang in Arunachal Pradesh were severely affected. Among different forest types, the maximum loss was seen in case of sal forest (37.97%) between 1975 and 2009 and is expected to deplete further to 60.39% by 2028. The tropical moist deciduous forest was the next category, which decreased from 5,208.11 km2 to 3,447.28 (33.81%) during same period with further chances of depletion to 2,288.81 km2 (56.05%) by 2028. It noted progressive loss of forests in the study area between 1975 and 2009 through 1990 and predicted that, unless checked, the area is in for further depletion of the invaluable climax forests in the region, especially sal and moist deciduous forests. The exercise demonstrated high potential of remote sensing and geographic information system for forest ecosystem dynamics assessment and the efficacy of CAMM to predict the forest cover change.

  16. FOREST ECOSYSTEM DYNAMICS ASSESSMENT AND PREDICTIVE MODELLING IN EASTERN HIMALAYA

    Directory of Open Access Journals (Sweden)

    S. P. S. Kushwaha

    2012-09-01

    Full Text Available This study focused on the forest ecosystem dynamics assessment and predictive modelling deforestation and forest cover prediction in a part of north-eastern India i.e. forest areas along West Bengal, Bhutan, Arunachal Pradesh and Assam border in Eastern Himalaya using temporal satellite imagery of 1975, 1990 and 2009 and predicted forest cover for the period 2028 using Cellular Automata Markov Modedel (CAMM. The exercise highlighted large-scale deforestation in the study area during 1975–1990 as well as 1990–2009 forest cover vectors. A net loss of 2,334.28 km2 forest cover was noticed between 1975 and 2009, and with current rate of deforestation, a forest area of 4,563.34 km2 will be lost by 2028. The annual rate of deforestation worked out to be 0.35 and 0.78% during 1975–1990 and 1990–2009 respectively. Bamboo forest increased by 24.98% between 1975 and 2009 due to opening up of the forests. Forests in Kokrajhar, Barpeta, Darrang, Sonitpur, and Dhemaji districts in Assam were noticed to be worst-affected while Lower Subansiri, West and East Siang, Dibang Valley, Lohit and Changlang in Arunachal Pradesh were severely affected. Among different forest types, the maximum loss was seen in case of sal forest (37.97% between 1975 and 2009 and is expected to deplete further to 60.39% by 2028. The tropical moist deciduous forest was the next category, which decreased from 5,208.11 km2 to 3,447.28 (33.81% during same period with further chances of depletion to 2,288.81 km2 (56.05% by 2028. It noted progressive loss of forests in the study area between 1975 and 2009 through 1990 and predicted that, unless checked, the area is in for further depletion of the invaluable climax forests in the region, especially sal and moist deciduous forests. The exercise demonstrated high potential of remote sensing and geographic information system for forest ecosystem dynamics assessment and the efficacy of CAMM to predict the forest cover change.

  17. Ecosystem-level water-use efficiency inferred from eddy covariance data: definitions, patterns and spatial up-scaling

    Science.gov (United States)

    Reichstein, M.; Beer, C.; Kuglitsch, F.; Papale, D.; Soussana, J. A.; Janssens, I.; Ciais, P.; Baldocchi, D.; Buchmann, N.; Verbeeck, H.; Ceulemans, R.; Moors, E.; Köstner, B.; Schulze, D.; Knohl, A.; Law, B. E.

    2007-12-01

    In this presentation we discuss ways to infer and to interpret water-use efficiency at ecosystem level (WUEe) from eddy covariance flux data and possibilities for scaling these patterns to regional and continental scale. In particular we convey the following: WUEe may be computed as a ratio of integrated fluxes or as the slope of carbon versus water fluxes offering different chances for interpretation. If computed from net ecosystem exchange and evapotranspiration on has to take of counfounding effects of respiration and soil evaporation. WUEe time-series at diurnal and seasonal scale is a valuable ecosystem physiological diagnostic for example about ecosystem-level responses to drought. Most often WUEe decreases during dry periods. The mean growing season ecosystem water-use efficiency of gross carbon uptake (WUEGPP) is highest in temperate broad-leaved deciduous forests, followed by temperate mixed forests, temperate evergreen conifers, Mediterranean broad-leaved deciduous forests, Mediterranean broad-leaved evergreen forests and Mediterranean evergreen conifers and boreal, grassland and tundra ecosystems. Water-use efficiency exhibits a temporally quite conservative relation with atmospheric water vapor pressure deficit (VPD) that is modified between sites by leaf area index (LAI) and soil quality, such that WUEe increases with LAI and soil water holding capacity which is related to texture. This property and tight coupling between carbon and water cycles is used to estimate catchment-scale water-use efficiency and primary productivity by integration of space-borne earth observation and river discharge data.

  18. 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.

  19. The indirect impact of long-term overbrowsing on insects in the Allegheny National Forest region of Pennsylvania

    Science.gov (United States)

    Michael J. Chips; Ellen H. Yerger; Arpad Hervanek; Tim Nuttle; Alex Royo; Jonathan N. Pruitt; Terrence P. McGlynn; Cynthia L. Riggall; Walter P. Carson

    2015-01-01

    Overbrowsing has created depauperate plant communities throughout the eastern deciduous forest. We hypothesized these low-diversity plant communities are associated with lower insect diversity. We compared insects inside and outside a 60-year-old fenced deer exclosure where plant species richness is 5x higher inside versus outside. We sampled aboveground and litter...

  20. Development, succession, and stand dynamics of upland oak forests in the Wisconsin Driftless Area: Implications for oak regeneration and management

    Science.gov (United States)

    Megan L. Buchanan; Kurt F. Kipfmueller; Anthony W. D' Amato

    2017-01-01

    Throughout the deciduous forests of the eastern United States, oak (Quercus) regeneration has declined in stands historically dominated by oak species. In the Wisconsin Driftless Area, the level of decline in oak regeneration is variable and influenced by stand structural development, historical disturbance regime, abiotic site characteristics, and...

  1. Analysis of nitrogen cycling in a forest stream during autumn using a 15N-tracer addition

    Science.gov (United States)

    Jennifer L. Tank; Judy L. Meyer; Diane M. Sanzone; Patrick J. Mulholland; Jackson R. Webster; Bruce J. Peterson; Wilfred M. Wollheim; Norman E. Leonard

    2000-01-01

    We added l5NH4Cl over 6 weeks to Upper Ball Creek, a second-order deciduous forest stream in the Appalachian Mountains, to follow the uptake, spiraling, and fate of nitrogen in a stream food web during autumn. A priori predictions of N flow and retention were made using a simple food web mass balance model. Values of ...

  2. The use of radiocarbon to constrain current and future soil organic matter turnover and transport in a temperate forest

    NARCIS (Netherlands)

    Braakhekke, M.C.; Beer, C.; Schrumpf, M.; Ahrens, B.; Hoosbeek, M.R.; Kruijt, B.; Kabat, P.; Reichstein, M.; Ekici, A.

    2014-01-01

    We investigated the merits of radiocarbon measurements for estimating soil organic matter (SOM) turnover and vertical transport for a temperate deciduous forest in Germany. Eleven parameters, defining decomposition and transport in the soil carbon model SOMPROF, were estimated using a Bayesian

  3. Tree growth and competition in a post-logging Quercus mongolica forest on Mt. Sobaek, South Korea

    Czech Academy of Sciences Publication Activity Database

    Doležal, Jiří; Song, J. S.; Altman, J.; Janeček, Štěpán; Černý, Tomáš; Šrůtek, Miroslav; Kolbek, Jiří

    2009-01-01

    Roč. 24, - (2009), s. 281-290 ISSN 0912-3814 R&D Projects: GA ČR GA206/05/0119 Institutional research plan: CEZ:AV0Z60050516 Keywords : Deciduous forests * stand recovery * spontaneous development Subject RIV: EF - Botanics Impact factor: 1.485, year: 2009

  4. Landsat analysis of tropical forest succession employing a terrain model

    Science.gov (United States)

    Barringer, T. H.; Robinson, V. B.; Coiner, J. C.; Bruce, R. C.

    1980-01-01

    Landsat multispectral scanner (MSS) data have yielded a dual classification of rain forest and shadow in an analysis of a semi-deciduous forest on Mindonoro Island, Philippines. Both a spatial terrain model, using a fifth side polynomial trend surface analysis for quantitatively estimating the general spatial variation in the data set, and a spectral terrain model, based on the MSS data, have been set up. A discriminant analysis, using both sets of data, has suggested that shadowing effects may be due primarily to local variations in the spectral regions and can therefore be compensated for through the decomposition of the spatial variation in both elevation and MSS data.

  5. Biogenic volatile organic compound (BVOC) emissions from forested areas in Turkey: Determination of specific emission rates for thirty-one tree species

    International Nuclear Information System (INIS)

    Aydin, Yagmur Meltem; Yaman, Baris; Koca, Husnu; Dasdemir, Okan; Kara, Melik; Altiok, Hasan; Dumanoglu, Yetkin; Bayram, Abdurrahman; Tolunay, Doganay; Odabasi, Mustafa; Elbir, Tolga

    2014-01-01

    Normalized biogenic volatile organic compound (BVOC) emission rates for thirty one tree species that cover the 98% of national forested areas in Turkey were determined. Field samplings were performed at fourteen different forested areas in Turkey using a specific dynamic enclosure system. The selected branches of tree species were enclosed in a chamber consisted of a transparent Nalofan bag. The air-flows were sampled from both inlet and outlet of the chamber by Tenax-filled sorbent tubes during photosynthesis of trees under the presence of sunlight. Several environmental parameters (temperature, humidity, photosynthetically active radiation-PAR, and CO 2 ) were continuously monitored inside and outside the enclosure chamber during the samplings. Collected samples were analyzed using a gas chromatography mass spectrometry (GC/MS) system equipped with a thermal desorber (TD). Sixty five BVOCs classified in five major groups (isoprene, monoterpenes, sesquiterpenes, oxygenated sesquiterpenes, and other oxygenated compounds) were analyzed. Emission rates were determined by normalization to standard conditions (1000 μmol/m 2 s PAR and 30 °C temperature for isoprene and 30 °C temperature for the remaining compounds). In agreement with the literature, isoprene was mostly emitted by broad-leaved trees while coniferous species mainly emitted monoterpenes. Several tree species such as Sweet Chestnut, Silver Lime, and European Alder had higher monoterpene emissions although they are broad-leaved species. High isoprene emissions were also observed for a few coniferous species such as Nordmann Fir and Oriental Spruce. The highest normalized total BVOC emission rate of 27.1 μg/g h was observed for Oriental Plane while South European Flowering Ash was the weakest BVOC emitter with a total normalized emission rate of 0.031 μg/g h. Monoterpene emissions of broad-leaved species mainly consisted of sabinene, limonene and trans-beta-ocimene, while alpha-pinene, beta-pinene and

  6. Biogenic volatile organic compound (BVOC) emissions from forested areas in Turkey: Determination of specific emission rates for thirty-one tree species

    Energy Technology Data Exchange (ETDEWEB)

    Aydin, Yagmur Meltem; Yaman, Baris; Koca, Husnu; Dasdemir, Okan; Kara, Melik; Altiok, Hasan; Dumanoglu, Yetkin; Bayram, Abdurrahman [Department of Environmental Engineering, Faculty of Engineering, Dokuz Eylul University, Tinaztepe Campus, Buca, Izmir (Turkey); Tolunay, Doganay [Department of Soil Science and Ecology, Faculty of Forestry, Istanbul University, Bahcekoy, Istanbul (Turkey); Odabasi, Mustafa [Department of Environmental Engineering, Faculty of Engineering, Dokuz Eylul University, Tinaztepe Campus, Buca, Izmir (Turkey); Elbir, Tolga, E-mail: tolga.elbir@deu.edu.tr [Department of Environmental Engineering, Faculty of Engineering, Dokuz Eylul University, Tinaztepe Campus, Buca, Izmir (Turkey)

    2014-08-15

    Normalized biogenic volatile organic compound (BVOC) emission rates for thirty one tree species that cover the 98% of national forested areas in Turkey were determined. Field samplings were performed at fourteen different forested areas in Turkey using a specific dynamic enclosure system. The selected branches of tree species were enclosed in a chamber consisted of a transparent Nalofan bag. The air-flows were sampled from both inlet and outlet of the chamber by Tenax-filled sorbent tubes during photosynthesis of trees under the presence of sunlight. Several environmental parameters (temperature, humidity, photosynthetically active radiation-PAR, and CO{sub 2}) were continuously monitored inside and outside the enclosure chamber during the samplings. Collected samples were analyzed using a gas chromatography mass spectrometry (GC/MS) system equipped with a thermal desorber (TD). Sixty five BVOCs classified in five major groups (isoprene, monoterpenes, sesquiterpenes, oxygenated sesquiterpenes, and other oxygenated compounds) were analyzed. Emission rates were determined by normalization to standard conditions (1000 μmol/m{sup 2} s PAR and 30 °C temperature for isoprene and 30 °C temperature for the remaining compounds). In agreement with the literature, isoprene was mostly emitted by broad-leaved trees while coniferous species mainly emitted monoterpenes. Several tree species such as Sweet Chestnut, Silver Lime, and European Alder had higher monoterpene emissions although they are broad-leaved species. High isoprene emissions were also observed for a few coniferous species such as Nordmann Fir and Oriental Spruce. The highest normalized total BVOC emission rate of 27.1 μg/g h was observed for Oriental Plane while South European Flowering Ash was the weakest BVOC emitter with a total normalized emission rate of 0.031 μg/g h. Monoterpene emissions of broad-leaved species mainly consisted of sabinene, limonene and trans-beta-ocimene, while alpha-pinene, beta

  7. Forest rights

    DEFF Research Database (Denmark)

    Balooni, Kulbhushan; Lund, Jens Friis

    2014-01-01

    One of the proposed strategies for implementation of reducing emissions from deforestation and forest degradation plus (REDD+) is to incentivize conservation of forests managed by communities under decentralized forest management. Yet, we argue that this is a challenging road to REDD+ because...... conservation of forests under existing decentralized management arrangements toward a push for extending the coverage of forests under decentralized management, making forest rights the hard currency of REDD+....

  8. Responses of the Carbon Storage and Sequestration Potential of Forest Vegetation to Temperature Increases in Yunnan Province, SW China

    Directory of Open Access Journals (Sweden)

    Ruiwu Zhou

    2018-04-01

    Full Text Available The distribution of forest vegetation and forest carbon sequestration potential are significantly influenced by climate change. In this study, a map of the current distribution of vegetation in Yunnan Province was compiled based on data from remote sensing imagery from the Advanced Land Observing Satellite (ALOS from 2008 to 2011. A classification and regression tree (CART model was used to predict the potential distribution of the main forest vegetation types in Yunnan Province and estimate the changes in carbon storage and carbon sequestration potential (CSP in response to increasing temperature. The results show that the current total forest area in Yunnan Province is 1.86 × 107 ha and that forest covers 48.63% of the area. As the temperature increases, the area of forest distribution first increases and then decreases, and it decreases by 11% when the temperature increases from 1.5 to 2 °C. The mean carbon density of the seven types of forest vegetation in Yunnan Province is 84.69 Mg/ha. The total carbon storage of the current forest vegetation in Yunnan Province is 871.14 TgC, and the CSP is 1100.61 TgC. The largest CSP (1114.82 TgC occurs when the temperature increases by 0.5 °C. Incremental warming of 2 °C will sharply decrease the forest CSP, especially in those regions with mature coniferous forest vegetation. Semi-humid evergreen broad-leaved forests were highly sensitive to temperature changes, and the CSP of these forests will decrease with increasing temperature. Warm-hot coniferous forests have the greatest CSP in all simulation scenarios except the scenario of a 2 °C temperature increase. These results indicate that temperature increases can influence the CSP in Yunnan Province, and the largest impact emerged in the 2 °C increase scenario.

  9. VARIAÇÃO DA ESTRUTURA DA FLORESTA ESTACIONAL DECIDUAL NO ESTADO DE SANTA CATARINA E SUA RELAÇÃO COM A ALTITUDE E CLIMA

    Directory of Open Access Journals (Sweden)

    André Luís de Gasper

    2015-01-01

    Full Text Available This study aims to identify structural similarities between the remnants of seasonal deciduous forest (SDF in Santa Catarina state and check the influence of environmental factors that leads the formation of these groups. Associated with this primary objective, it was also sought to identify the areas of contact between this forest type and Araucaria forest (mixed ombrophilous forest – MOF. We analyzed data from 78 sample units (AU installed in the remnants of SDF between 2008 and 2009 by professional team of Floristic and Forest Inventory of Santa Catarina project (IFFSC. The data were processed through the Detrended Correspondence Analysis (DCA and Canonical Correspondence Analysis (CCA, using a matrix of species density associated with a environmental variables matrix, that consisted of altitude and climate parameters. The proportion of variance explained by the first three axes of DCA was low, accounting for approximately 21% of the information contained in the original data set. This result provides low power of interpretation of the results. However, when DCA was applied to the data of mean density of species in each river basin, the results pointed to better explanatory eigenvectors (three first eigenvectors explain 58.1% of total variance. The first ordination axis of DCA grouped the eastern watersheds SUs at one end, and the western watersheds SUs at the other end of this axis. At the right end of the first axis are arranged the watersheds of the river Canoas, Pelotas and Peixe, which are characterized by the presence of species such as Ocotea pulchella, Zanthoxylum fagara, Lithrea brasiliensis, Matayba elaeagnoides, Cinnamodendron dinisii commonly associated with Mixed Ombrophilous Forest (Araucaria forest. At the left end, the grouped SUs are mainly those of western watersheds, a group that includes the basins of the Jacutinga, Irani, Chapecó, Antas and Peperi-guaçu rivers. Among the species that most strongly influence the

  10. Enamel thickness variation of deciduous first and second upper molars in modern humans and Neanderthals

    Czech Academy of Sciences Publication Activity Database

    Fornai, C.; Benazzi, S.; Svoboda, Jiří; Pap, I.; Harvati, K.; Weber, G. W.

    2014-01-01

    Roč. 76, November (2014), s. 83-91 ISSN 0047-2484 Institutional support: RVO:68081758 Keywords : Dental tissue proportions * Tooth wear * Deciduous dentition * Homo neanderthalensis * Homo sapiens * Pleistocene Subject RIV: AC - Archeology, Anthropology, Ethnology OBOR OECD: Archaeology Impact factor: 3.733, year: 2014

  11. 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

  12. 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.

  13. 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)

  14. Evaluation in vitro of pulpal chamber temperature of deciduous teeth during Er:YAG laser application

    International Nuclear Information System (INIS)

    Sznajder, Alexandre Joseph

    2001-01-01

    The Er:YAG laser technology has been thoroughly studied, since its invention, and has been increasingly recommended in Dentistry. However, its use in deciduous teeth has not been deserving the equivalent attention to its counterpart in permanent teeth, despite of the deciduous teething occur in a phase of life in which it has a far more importance than its substitutes. For that reason, this study aims to identify the suitable parameters to the clinic procedures in deciduous teeth, using the already established protocols in permanent teeth. The study was lead in a way to resemble the most the conditions of the clinical use of the laser. Five groups were analyzed using different energy densities and repetition rates. Each group was composed of 10 first superior right deciduous molars randomly selected. The energy densities and repetition rates used for each group were: 60 mJ 15 Hz, 250 mJ 2 Hz, 250 mJ 15 Hz, 400 mJ 6 Hz and 500 mJ 2 Hz. The results obtained allowed us to conclude that the use of the Er:YAG laser in Odontopediatrics is effective, safe and secure and the main reason for its recommendation is the low transfer of heat to the adjacent tissues of the applied surfaces. (author)

  15. The study of barium concentration in deciduous teeth, impacted teeth, and facial bones of Polish residents.

    Science.gov (United States)

    Fischer, Agnieszka; Malara, Piotr; Wiechuła, Danuta

    2014-10-01

    The study determines the concentration of Ba in mineralized tissues of deciduous teeth, permanent impacted teeth, and facial bones. The study covers the population of children and adults (aged 6-78) living in an industrial area of Poland. Teeth were analyzed in whole, with no division into dentine and enamel. Facial bones and teeth were subjected to the following preparation: washing, drying, grinding in a porcelain mortar, sample weighing (about 0.2 g), and microwave mineralization with spectrally pure nitric acid. The aim of the study was to determinate the concentration of Ba in deciduous teeth, impacted permanent teeth, and facial bones. The concentration of barium in samples was determined over the ICP OES method. The Ba concentration in the tested bone tissues amounted to 2.2-15.5 μg/g (6.6 μg/g ± 3.9). The highest concentration of Ba was present in deciduous teeth (10.5 μg/g), followed by facial bones (5.2 μg/g), and impacted teeth (4.3 μg/g) (ANOVA Kruskal-Wallis rank test, p = 0.0002). In bone tissue and impacted teeth, Ba concentration increased with age. In deciduous teeth, the level of Ba decreased with children's age.

  16. Spontaneous correction of anterior crossbite by RPE anchored on deciduous teeth in the early mixed dentition.

    Science.gov (United States)

    Rosa, M; Lucchi, P; Mariani, L; Caprioglio, A

    2012-09-01

    The purpose of this study was to evaluate the effectiveness of Haas RPE anchored on deciduous teeth in the early mixed dentition, for inducing the spontaneous correction of permanent incisor's crossbite, without compliance, without post bite-plane and no involvement of the permanent teeth. The sample group comprised 50 consecutive patients (mean age 8y 5m, SD 2y 1m), 31 males, 19 females. They showed a cross-bite affecting one or more permanent incisors, for a total of 70 teeth. The patients were treated with Haas RPE appliance anchored on second deciduous molars and bonded on deciduous canines. No direct forces were applied on the permanent teeth. Anterior crossbite self-corrected 'spontaneously' in 84% of the cases. Lateral incisors had a higher rate of self-correction than central incisors. All hyper-divergent subjects showed a spontaneous crossbite self-correction. The early maxillary expansion by Haas RPE anchored on deciduous teeth is an efficient and effective procedure to induce the anterior crossbite self-correction in the early mixed dentition without the need of a bite-plane, no involvement of the permanent teeth and without compliance.

  17. Modified distal shoe appliance fo